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Time Travel

There is an extensive literature on time travel in both philosophy and physics. Part of the great interest of the topic stems from the fact that reasons have been given both for thinking that time travel is physically possible—and for thinking that it is logically impossible! This entry deals primarily with philosophical issues; issues related to the physics of time travel are covered in the separate entries on time travel and modern physics and time machines . We begin with the definitional question: what is time travel? We then turn to the major objection to the possibility of backwards time travel: the Grandfather paradox. Next, issues concerning causation are discussed—and then, issues in the metaphysics of time and change. We end with a discussion of the question why, if backwards time travel will ever occur, we have not been visited by time travellers from the future.

1.1 Time Discrepancy

1.2 changing the past, 2.1 can and cannot, 2.2 improbable coincidences, 2.3 inexplicable occurrences, 3.1 backwards causation, 3.2 causal loops, 4.1 time travel and time, 4.2 time travel and change, 5. where are the time travellers, other internet resources, related entries, 1. what is time travel.

There is a number of rather different scenarios which would seem, intuitively, to count as ‘time travel’—and a number of scenarios which, while sharing certain features with some of the time travel cases, seem nevertheless not to count as genuine time travel: [ 1 ]

Time travel Doctor . Doctor Who steps into a machine in 2024. Observers outside the machine see it disappear. Inside the machine, time seems to Doctor Who to pass for ten minutes. Observers in 1984 (or 3072) see the machine appear out of nowhere. Doctor Who steps out. [ 2 ] Leap . The time traveller takes hold of a special device (or steps into a machine) and suddenly disappears; she appears at an earlier (or later) time. Unlike in Doctor , the time traveller experiences no lapse of time between her departure and arrival: from her point of view, she instantaneously appears at the destination time. [ 3 ] Putnam . Oscar Smith steps into a machine in 2024. From his point of view, things proceed much as in Doctor : time seems to Oscar Smith to pass for a while; then he steps out in 1984. For observers outside the machine, things proceed differently. Observers of Oscar’s arrival in the past see a time machine suddenly appear out of nowhere and immediately divide into two copies of itself: Oscar Smith steps out of one; and (through the window) they see inside the other something that looks just like what they would see if a film of Oscar Smith were played backwards (his hair gets shorter; food comes out of his mouth and goes back into his lunch box in a pristine, uneaten state; etc.). Observers of Oscar’s departure from the future do not simply see his time machine disappear after he gets into it: they see it collide with the apparently backwards-running machine just described, in such a way that both are simultaneously annihilated. [ 4 ] Gödel . The time traveller steps into an ordinary rocket ship (not a special time machine) and flies off on a certain course. At no point does she disappear (as in Leap ) or ‘turn back in time’ (as in Putnam )—yet thanks to the overall structure of spacetime (as conceived in the General Theory of Relativity), the traveller arrives at a point in the past (or future) of her departure. (Compare the way in which someone can travel continuously westwards, and arrive to the east of her departure point, thanks to the overall curved structure of the surface of the earth.) [ 5 ] Einstein . The time traveller steps into an ordinary rocket ship and flies off at high speed on a round trip. When he returns to Earth, thanks to certain effects predicted by the Special Theory of Relativity, only a very small amount of time has elapsed for him—he has aged only a few months—while a great deal of time has passed on Earth: it is now hundreds of years in the future of his time of departure. [ 6 ] Not time travel Sleep . One is very tired, and falls into a deep sleep. When one awakes twelve hours later, it seems from one’s own point of view that hardly any time has passed. Coma . One is in a coma for a number of years and then awakes, at which point it seems from one’s own point of view that hardly any time has passed. Cryogenics . One is cryogenically frozen for hundreds of years. Upon being woken, it seems from one’s own point of view that hardly any time has passed. Virtual . One enters a highly realistic, interactive virtual reality simulator in which some past era has been recreated down to the finest detail. Crystal . One looks into a crystal ball and sees what happened at some past time, or will happen at some future time. (Imagine that the crystal ball really works—like a closed-circuit security monitor, except that the vision genuinely comes from some past or future time. Even so, the person looking at the crystal ball is not thereby a time traveller.) Waiting . One enters one’s closet and stays there for seven hours. When one emerges, one has ‘arrived’ seven hours in the future of one’s ‘departure’. Dateline . One departs at 8pm on Monday, flies for fourteen hours, and arrives at 10pm on Monday.

A satisfactory definition of time travel would, at least, need to classify the cases in the right way. There might be some surprises—perhaps, on the best definition of ‘time travel’, Cryogenics turns out to be time travel after all—but it should certainly be the case, for example, that Gödel counts as time travel and that Sleep and Waiting do not. [ 7 ]

In fact there is no entirely satisfactory definition of ‘time travel’ in the literature. The most popular definition is the one given by Lewis (1976, 145–6):

What is time travel? Inevitably, it involves a discrepancy between time and time. Any traveller departs and then arrives at his destination; the time elapsed from departure to arrival…is the duration of the journey. But if he is a time traveller, the separation in time between departure and arrival does not equal the duration of his journey.…How can it be that the same two events, his departure and his arrival, are separated by two unequal amounts of time?…I reply by distinguishing time itself, external time as I shall also call it, from the personal time of a particular time traveller: roughly, that which is measured by his wristwatch. His journey takes an hour of his personal time, let us say…But the arrival is more than an hour after the departure in external time, if he travels toward the future; or the arrival is before the departure in external time…if he travels toward the past.

This correctly excludes Waiting —where the length of the ‘journey’ precisely matches the separation between ‘arrival’ and ‘departure’—and Crystal , where there is no journey at all—and it includes Doctor . It has trouble with Gödel , however—because when the overall structure of spacetime is as twisted as it is in the sort of case Gödel imagined, the notion of external time (“time itself”) loses its grip.

Another definition of time travel that one sometimes encounters in the literature (Arntzenius, 2006, 602) (Smeenk and Wüthrich, 2011, 5, 26) equates time travel with the existence of CTC’s: closed timelike curves. A curve in this context is a line in spacetime; it is timelike if it could represent the career of a material object; and it is closed if it returns to its starting point (i.e. in spacetime—not merely in space). This now includes Gödel —but it excludes Einstein .

The lack of an adequate definition of ‘time travel’ does not matter for our purposes here. [ 8 ] It suffices that we have clear cases of (what would count as) time travel—and that these cases give rise to all the problems that we shall wish to discuss.

Some authors (in philosophy, physics and science fiction) consider ‘time travel’ scenarios in which there are two temporal dimensions (e.g. Meiland (1974)), and others consider scenarios in which there are multiple ‘parallel’ universes—each one with its own four-dimensional spacetime (e.g. Deutsch and Lockwood (1994)). There is a question whether travelling to another version of 2001 (i.e. not the very same version one experienced in the past)—a version at a different point on the second time dimension, or in a different parallel universe—is really time travel, or whether it is more akin to Virtual . In any case, this kind of scenario does not give rise to many of the problems thrown up by the idea of travelling to the very same past one experienced in one’s younger days. It is these problems that form the primary focus of the present entry, and so we shall not have much to say about other kinds of ‘time travel’ scenario in what follows.

One objection to the possibility of time travel flows directly from attempts to define it in anything like Lewis’s way. The worry is that because time travel involves “a discrepancy between time and time”, time travel scenarios are simply incoherent. The time traveller traverses thirty years in one year; she is 51 years old 21 years after her birth; she dies at the age of 100, 200 years before her birth; and so on. The objection is that these are straightforward contradictions: the basic description of what time travel involves is inconsistent; therefore time travel is logically impossible. [ 9 ]

There must be something wrong with this objection, because it would show Einstein to be logically impossible—whereas this sort of future-directed time travel has actually been observed (albeit on a much smaller scale—but that does not affect the present point) (Hafele and Keating, 1972b,a). The most common response to the objection is that there is no contradiction because the interval of time traversed by the time traveller and the duration of her journey are measured with respect to different frames of reference: there is thus no reason why they should coincide. A similar point applies to the discrepancy between the time elapsed since the time traveller’s birth and her age upon arrival. There is no more of a contradiction here than in the fact that Melbourne is both 800 kilometres away from Sydney—along the main highway—and 1200 kilometres away—along the coast road. [ 10 ]

Before leaving the question ‘What is time travel?’ we should note the crucial distinction between changing the past and participating in (aka affecting or influencing) the past. [ 11 ] In the popular imagination, backwards time travel would allow one to change the past: to right the wrongs of history, to prevent one’s younger self doing things one later regretted, and so on. In a model with a single past, however, this idea is incoherent: the very description of the case involves a contradiction (e.g. the time traveller burns all her diaries at midnight on her fortieth birthday in 1976, and does not burn all her diaries at midnight on her fortieth birthday in 1976). It is not as if there are two versions of the past: the original one, without the time traveller present, and then a second version, with the time traveller playing a role. There is just one past—and two perspectives on it: the perspective of the younger self, and the perspective of the older time travelling self. If these perspectives are inconsistent (e.g. an event occurs in one but not the other) then the time travel scenario is incoherent.

This means that time travellers can do less than we might have hoped: they cannot right the wrongs of history; they cannot even stir a speck of dust on a certain day in the past if, on that day, the speck was in fact unmoved. But this does not mean that time travellers must be entirely powerless in the past: while they cannot do anything that did not actually happen, they can (in principle) do anything that did happen. Time travellers cannot change the past: they cannot make it different from the way it was—but they can participate in it: they can be amongst the people who did make the past the way it was. [ 12 ]

What about models involving two temporal dimensions, or parallel universes—do they allow for coherent scenarios in which the past is changed? [ 13 ] There is certainly no contradiction in saying that the time traveller burns all her diaries at midnight on her fortieth birthday in 1976 in universe 1 (or at hypertime A ), and does not burn all her diaries at midnight on her fortieth birthday in 1976 in universe 2 (or at hypertime B ). The question is whether this kind of story involves changing the past in the sense originally envisaged: righting the wrongs of history, preventing subsequently regretted actions, and so on. Goddu (2003) and van Inwagen (2010) argue that it does (in the context of particular hypertime models), while Smith (1997, 365–6; 2015) argues that it does not: that it involves avoiding the past—leaving it untouched while travelling to a different version of the past in which things proceed differently.

2. The Grandfather Paradox

The most important objection to the logical possibility of backwards time travel is the so-called Grandfather paradox. This paradox has actually convinced many people that backwards time travel is impossible:

The dead giveaway that true time-travel is flatly impossible arises from the well-known “paradoxes” it entails. The classic example is “What if you go back into the past and kill your grandfather when he was still a little boy?”…So complex and hopeless are the paradoxes…that the easiest way out of the irrational chaos that results is to suppose that true time-travel is, and forever will be, impossible. (Asimov 1995 [2003, 276–7]) travel into one’s past…would seem to give rise to all sorts of logical problems, if you were able to change history. For example, what would happen if you killed your parents before you were born. It might be that one could avoid such paradoxes by some modification of the concept of free will. But this will not be necessary if what I call the chronology protection conjecture is correct: The laws of physics prevent closed timelike curves from appearing . (Hawking, 1992, 604) [ 14 ]

The paradox comes in different forms. Here’s one version:

If time travel was logically possible then the time traveller could return to the past and in a suicidal rage destroy his time machine before it was completed and murder his younger self. But if this was so a necessary condition for the time trip to have occurred at all is removed, and we should then conclude that the time trip did not occur. Hence if the time trip did occur, then it did not occur. Hence it did not occur, and it is necessary that it did not occur. To reply, as it is standardly done, that our time traveller cannot change the past in this way, is a petitio principii . Why is it that the time traveller is constrained in this way? What mysterious force stills his sudden suicidal rage? (Smith, 1985, 58)

The idea is that backwards time travel is impossible because if it occurred, time travellers would attempt to do things such as kill their younger selves (or their grandfathers etc.). We know that doing these things—indeed, changing the past in any way—is impossible. But were there time travel, there would then be nothing left to stop these things happening. If we let things get to the stage where the time traveller is facing Grandfather with a loaded weapon, then there is nothing left to prevent the impossible from occurring. So we must draw the line earlier: it must be impossible for someone to get into this situation at all; that is, backwards time travel must be impossible.

In order to defend the possibility of time travel in the face of this argument we need to show that time travel is not a sure route to doing the impossible. So, given that a time traveller has gone to the past and is facing Grandfather, what could stop her killing Grandfather? Some science fiction authors resort to the idea of chaperones or time guardians who prevent time travellers from changing the past—or to mysterious forces of logic. But it is hard to take these ideas seriously—and more importantly, it is hard to make them work in detail when we remember that changing the past is impossible. (The chaperone is acting to ensure that the past remains as it was—but the only reason it ever was that way is because of his very actions.) [ 15 ] Fortunately there is a better response—also to be found in the science fiction literature, and brought to the attention of philosophers by Lewis (1976). What would stop the time traveller doing the impossible? She would fail “for some commonplace reason”, as Lewis (1976, 150) puts it. Her gun might jam, a noise might distract her, she might slip on a banana peel, etc. Nothing more than such ordinary occurrences is required to stop the time traveller killing Grandfather. Hence backwards time travel does not entail the occurrence of impossible events—and so the above objection is defused.

A problem remains. Suppose Tim, a time-traveller, is facing his grandfather with a loaded gun. Can Tim kill Grandfather? On the one hand, yes he can. He is an excellent shot; there is no chaperone to stop him; the laws of logic will not magically stay his hand; he hates Grandfather and will not hesitate to pull the trigger; etc. On the other hand, no he can’t. To kill Grandfather would be to change the past, and no-one can do that (not to mention the fact that if Grandfather died, then Tim would not have been born). So we have a contradiction: Tim can kill Grandfather and Tim cannot kill Grandfather. Time travel thus leads to a contradiction: so it is impossible.

Note the difference between this version of the Grandfather paradox and the version considered above. In the earlier version, the contradiction happens if Tim kills Grandfather. The solution was to say that Tim can go into the past without killing Grandfather—hence time travel does not entail a contradiction. In the new version, the contradiction happens as soon as Tim gets to the past. Of course Tim does not kill Grandfather—but we still have a contradiction anyway: for he both can do it, and cannot do it. As Lewis puts it:

Could a time traveler change the past? It seems not: the events of a past moment could no more change than numbers could. Yet it seems that he would be as able as anyone to do things that would change the past if he did them. If a time traveler visiting the past both could and couldn’t do something that would change it, then there cannot possibly be such a time traveler. (Lewis, 1976, 149)

Lewis’s own solution to this problem has been widely accepted. [ 16 ] It turns on the idea that to say that something can happen is to say that its occurrence is compossible with certain facts, where context determines (more or less) which facts are the relevant ones. Tim’s killing Grandfather in 1921 is compossible with the facts about his weapon, training, state of mind, and so on. It is not compossible with further facts, such as the fact that Grandfather did not die in 1921. Thus ‘Tim can kill Grandfather’ is true in one sense (relative to one set of facts) and false in another sense (relative to another set of facts)—but there is no single sense in which it is both true and false. So there is no contradiction here—merely an equivocation.

Another response is that of Vihvelin (1996), who argues that there is no contradiction here because ‘Tim can kill Grandfather’ is simply false (i.e. contra Lewis, there is no legitimate sense in which it is true). According to Vihvelin, for ‘Tim can kill Grandfather’ to be true, there must be at least some occasions on which ‘If Tim had tried to kill Grandfather, he would or at least might have succeeded’ is true—but, Vihvelin argues, at any world remotely like ours, the latter counterfactual is always false. [ 17 ]

Return to the original version of the Grandfather paradox and Lewis’s ‘commonplace reasons’ response to it. This response engenders a new objection—due to Horwich (1987)—not to the possibility but to the probability of backwards time travel.

Think about correlated events in general. Whenever we see two things frequently occurring together, this is because one of them causes the other, or some third thing causes both. Horwich calls this the Principle of V-Correlation:

if events of type A and B are associated with one another, then either there is always a chain of events between them…or else we find an earlier event of type C that links up with A and B by two such chains of events. What we do not see is…an inverse fork—in which A and B are connected only with a characteristic subsequent event, but no preceding one. (Horwich, 1987, 97–8)

For example, suppose that two students turn up to class wearing the same outfits. That could just be a coincidence (i.e. there is no common cause, and no direct causal link between the two events). If it happens every week for the whole semester, it is possible that it is a coincidence, but this is extremely unlikely . Normally, we see this sort of extensive correlation only if either there is a common cause (e.g. both students have product endorsement deals with the same clothing company, or both slavishly copy the same influencer) or a direct causal link (e.g. one student is copying the other).

Now consider the time traveller setting off to kill her younger self. As discussed, no contradiction need ensue—this is prevented not by chaperones or mysterious forces, but by a run of ordinary occurrences in which the trigger falls off the time traveller’s gun, a gust of wind pushes her bullet off course, she slips on a banana peel, and so on. But now consider this run of ordinary occurrences. Whenever the time traveller contemplates auto-infanticide, someone nearby will drop a banana peel ready for her to slip on, or a bird will begin to fly so that it will be in the path of the time traveller’s bullet by the time she fires, and so on. In general, there will be a correlation between auto-infanticide attempts and foiling occurrences such as the presence of banana peels—and this correlation will be of the type that does not involve a direct causal connection between the correlated events or a common cause of both. But extensive correlations of this sort are, as we saw, extremely rare—so backwards time travel will happen about as often as you will see two people wear the same outfits to class every day of semester, without there being any causal connection between what one wears and what the other wears.

We can set out Horwich’s argument this way:

If time travel were ever to occur, we should see extensive uncaused correlations.
It is extremely unlikely that we should ever see extensive uncaused correlations.
Therefore time travel is extremely unlikely to occur.

The conclusion is not that time travel is impossible, but that we should treat it the way we treat the possibility of, say, tossing a fair coin and getting heads one thousand times in a row. As Price (1996, 278 n.7) puts it—in the context of endorsing Horwich’s conclusion: “the hypothesis of time travel can be made to imply propositions of arbitrarily low probability. This is not a classical reductio, but it is as close as science ever gets.”

Smith (1997) attacks both premisses of Horwich’s argument. Against the first premise, he argues that backwards time travel, in itself, does not entail extensive uncaused correlations. Rather, when we look more closely, we see that time travel scenarios involving extensive uncaused correlations always build in prior coincidences which are themselves highly unlikely. Against the second premise, he argues that, from the fact that we have never seen extensive uncaused correlations, it does not follow that we never shall. This is not inductive scepticism: let us assume (contra the inductive sceptic) that in the absence of any specific reason for thinking things should be different in the future, we are entitled to assume they will continue being the same; still we cannot dismiss a specific reason for thinking the future will be a certain way simply on the basis that things have never been that way in the past. You might reassure an anxious friend that the sun will certainly rise tomorrow because it always has in the past—but you cannot similarly refute an astronomer who claims to have discovered a specific reason for thinking that the earth will stop rotating overnight.

Sider (2002, 119–20) endorses Smith’s second objection. Dowe (2003) criticises Smith’s first objection, but agrees with the second, concluding overall that time travel has not been shown to be improbable. Ismael (2003) reaches a similar conclusion. Goddu (2007) criticises Smith’s first objection to Horwich. Further contributions to the debate include Arntzenius (2006), Smeenk and Wüthrich (2011, §2.2) and Elliott (2018). For other arguments to the same conclusion as Horwich’s—that time travel is improbable—see Ney (2000) and Effingham (2020).

Return again to the original version of the Grandfather paradox and Lewis’s ‘commonplace reasons’ response to it. This response engenders a further objection. The autoinfanticidal time traveller is attempting to do something impossible (render herself permanently dead from an age younger than her age at the time of the attempts). Suppose we accept that she will not succeed and that what will stop her is a succession of commonplace occurrences. The previous objection was that such a succession is improbable . The new objection is that the exclusion of the time traveler from successfully committing auto-infanticide is mysteriously inexplicable . The worry is as follows. Each particular event that foils the time traveller is explicable in a perfectly ordinary way; but the inevitable combination of these events amounts to a ring-fencing of the forbidden zone of autoinfanticide—and this ring-fencing is mystifying. It’s like a grand conspiracy to stop the time traveler from doing what she wants to do—and yet there are no conspirators: no time lords, no magical forces of logic. This is profoundly perplexing. Riggs (1997, 52) writes: “Lewis’s account may do for a once only attempt, but is untenable as a general explanation of Tim’s continual lack of success if he keeps on trying.” Ismael (2003, 308) writes: “Considered individually, there will be nothing anomalous in the explanations…It is almost irresistible to suppose, however, that there is something anomalous in the cases considered collectively, i.e., in our unfailing lack of success.” See also Gorovitz (1964, 366–7), Horwich (1987, 119–21) and Carroll (2010, 86).

There have been two different kinds of defense of time travel against the objection that it involves mysteriously inexplicable occurrences. Baron and Colyvan (2016, 70) agree with the objectors that a purely causal explanation of failure—e.g. Tim fails to kill Grandfather because first he slips on a banana peel, then his gun jams, and so on—is insufficient. However they argue that, in addition, Lewis offers a non-causal—a logical —explanation of failure: “What explains Tim’s failure to kill his grandfather, then, is something about logic; specifically: Tim fails to kill his grandfather because the law of non-contradiction holds.” Smith (2017) argues that the appearance of inexplicability is illusory. There are no scenarios satisfying the description ‘a time traveller commits autoinfanticide’ (or changes the past in any other way) because the description is self-contradictory (e.g. it involves the time traveller permanently dying at 20 and also being alive at 40). So whatever happens it will not be ‘that’. There is literally no way for the time traveller not to fail. Hence there is no need for—or even possibility of—a substantive explanation of why failure invariably occurs, and such failure is not perplexing.

3. Causation

Backwards time travel scenarios give rise to interesting issues concerning causation. In this section we examine two such issues.

Earlier we distinguished changing the past and affecting the past, and argued that while the former is impossible, backwards time travel need involve only the latter. Affecting the past would be an example of backwards causation (i.e. causation where the effect precedes its cause)—and it has been argued that this too is impossible, or at least problematic. [ 18 ] The classic argument against backwards causation is the bilking argument . [ 19 ] Faced with the claim that some event A causes an earlier event B , the proponent of the bilking objection recommends an attempt to decorrelate A and B —that is, to bring about A in cases in which B has not occurred, and to prevent A in cases in which B has occurred. If the attempt is successful, then B often occurs despite the subsequent nonoccurrence of A , and A often occurs without B occurring, and so A cannot be the cause of B . If, on the other hand, the attempt is unsuccessful—if, that is, A cannot be prevented when B has occurred, nor brought about when B has not occurred—then, it is argued, it must be B that is the cause of A , rather than vice versa.

The bilking procedure requires repeated manipulation of event A . Thus, it cannot get under way in cases in which A is either unrepeatable or unmanipulable. Furthermore, the procedure requires us to know whether or not B has occurred, prior to manipulating A —and thus, it cannot get under way in cases in which it cannot be known whether or not B has occurred until after the occurrence or nonoccurrence of A (Dummett, 1964). These three loopholes allow room for many claims of backwards causation that cannot be touched by the bilking argument, because the bilking procedure cannot be performed at all. But what about those cases in which it can be performed? If the procedure succeeds—that is, A and B are decorrelated—then the claim that A causes B is refuted, or at least weakened (depending upon the details of the case). But if the bilking attempt fails, it does not follow that it must be B that is the cause of A , rather than vice versa. Depending upon the situation, that B causes A might become a viable alternative to the hypothesis that A causes B —but there is no reason to think that this alternative must always be the superior one. For example, suppose that I see a photo of you in a paper dated well before your birth, accompanied by a report of your arrival from the future. I now try to bilk your upcoming time trip—but I slip on a banana peel while rushing to push you away from your time machine, my time travel horror stories only inspire you further, and so on. Or again, suppose that I know that you were not in Sydney yesterday. I now try to get you to go there in your time machine—but first I am struck by lightning, then I fall down a manhole, and so on. What does all this prove? Surely not that your arrival in the past causes your departure from the future. Depending upon the details of the case, it seems that we might well be entitled to describe it as involving backwards time travel and backwards causation. At least, if we are not so entitled, this must be because of other facts about the case: it would not follow simply from the repeated coincidental failures of my bilking attempts.

Backwards time travel would apparently allow for the possibility of causal loops, in which things come from nowhere. The things in question might be objects—imagine a time traveller who steals a time machine from the local museum in order to make his time trip and then donates the time machine to the same museum at the end of the trip (i.e. in the past). In this case the machine itself is never built by anyone—it simply exists. The things in question might be information—imagine a time traveller who explains the theory behind time travel to her younger self: theory that she herself knows only because it was explained to her in her youth by her time travelling older self. The things in question might be actions. Imagine a time traveller who visits his younger self. When he encounters his younger self, he suddenly has a vivid memory of being punched on the nose by a strange visitor. He realises that this is that very encounter—and resignedly proceeds to punch his younger self. Why did he do it? Because he knew that it would happen and so felt that he had to do it—but he only knew it would happen because he in fact did it. [ 20 ]

One might think that causal loops are impossible—and hence that insofar as backwards time travel entails such loops, it too is impossible. [ 21 ] There are two issues to consider here. First, does backwards time travel entail causal loops? Lewis (1976, 148) raises the question whether there must be causal loops whenever there is backwards causation; in response to the question, he says simply “I am not sure.” Mellor (1998, 131) appears to claim a positive answer to the question. [ 22 ] Hanley (2004, 130) defends a negative answer by telling a time travel story in which there is backwards time travel and backwards causation, but no causal loops. [ 23 ] Monton (2009) criticises Hanley’s counterexample, but also defends a negative answer via different counterexamples. Effingham (2020) too argues for a negative answer.

Second, are causal loops impossible, or in some other way objectionable? One objection is that causal loops are inexplicable . There have been two main kinds of response to this objection. One is to agree but deny that this is a problem. Lewis (1976, 149) accepts that a loop (as a whole) would be inexplicable—but thinks that this inexplicability (like that of the Big Bang or the decay of a tritium atom) is merely strange, not impossible. In a similar vein, Meyer (2012, 263) argues that if someone asked for an explanation of a loop (as a whole), “the blame would fall on the person asking the question, not on our inability to answer it.” The second kind of response (Hanley, 2004, §5) is to deny that (all) causal loops are inexplicable. A second objection to causal loops, due to Mellor (1998, ch.12), is that in such loops the chances of events would fail to be related to their frequencies in accordance with the law of large numbers. Berkovitz (2001) and Dowe (2001) both argue that Mellor’s objection fails to establish the impossibility of causal loops. [ 24 ] Effingham (2020) considers—and rebuts—some additional objections to the possibility of causal loops.

4. Time and Change

Gödel (1949a [1990a])—in which Gödel presents models of Einstein’s General Theory of Relativity in which there exist CTC’s—can well be regarded as initiating the modern academic literature on time travel, in both philosophy and physics. In a companion paper, Gödel discusses the significance of his results for more general issues in the philosophy of time (Gödel 1949b [1990b]). For the succeeding half century, the time travel literature focussed predominantly on objections to the possibility (or probability) of time travel. More recently, however, there has been renewed interest in the connections between time travel and more general issues in the metaphysics of time and change. We examine some of these in the present section. [ 25 ]

The first thing that we need to do is set up the various metaphysical positions whose relationships with time travel will then be discussed. Consider two metaphysical questions:

Are the past, present and future equally real?
Is there an objective flow or passage of time, and an objective now?

We can label some views on the first question as follows. Eternalism is the view that past and future times, objects and events are just as real as the present time and present events and objects. Nowism is the view that only the present time and present events and objects exist. Now-and-then-ism is the view that the past and present exist but the future does not. We can also label some views on the second question. The A-theory answers in the affirmative: the flow of time and division of events into past (before now), present (now) and future (after now) are objective features of reality (as opposed to mere features of our experience). Furthermore, they are linked: the objective flow of time arises from the movement, through time, of the objective now (from the past towards the future). The B-theory answers in the negative: while we certainly experience now as special, and time as flowing, the B-theory denies that what is going on here is that we are detecting objective features of reality in a way that corresponds transparently to how those features are in themselves. The flow of time and the now are not objective features of reality; they are merely features of our experience. By combining answers to our first and second questions we arrive at positions on the metaphysics of time such as: [ 26 ]

the block universe view: eternalism + B-theory
the moving spotlight view: eternalism + A-theory
the presentist view: nowism + A-theory
the growing block view: now-and-then-ism + A-theory.

So much for positions on time itself. Now for some views on temporal objects: objects that exist in (and, in general, change over) time. Three-dimensionalism is the view that persons, tables and other temporal objects are three-dimensional entities. On this view, what you see in the mirror is a whole person. [ 27 ] Tomorrow, when you look again, you will see the whole person again. On this view, persons and other temporal objects are wholly present at every time at which they exist. Four-dimensionalism is the view that persons, tables and other temporal objects are four-dimensional entities, extending through three dimensions of space and one dimension of time. On this view, what you see in the mirror is not a whole person: it is just a three-dimensional temporal part of a person. Tomorrow, when you look again, you will see a different such temporal part. Say that an object persists through time if it is around at some time and still around at a later time. Three- and four-dimensionalists agree that (some) objects persist, but they differ over how objects persist. According to three-dimensionalists, objects persist by enduring : an object persists from t 1 to t 2 by being wholly present at t 1 and t 2 and every instant in between. According to four-dimensionalists, objects persist by perduring : an object persists from t 1 to t 2 by having temporal parts at t 1 and t 2 and every instant in between. Perduring can be usefully compared with being extended in space: a road extends from Melbourne to Sydney not by being wholly located at every point in between, but by having a spatial part at every point in between.

It is natural to combine three-dimensionalism with presentism and four-dimensionalism with the block universe view—but other combinations of views are certainly possible.

Gödel (1949b [1990b]) argues from the possibility of time travel (more precisely, from the existence of solutions to the field equations of General Relativity in which there exist CTC’s) to the B-theory: that is, to the conclusion that there is no objective flow or passage of time and no objective now. Gödel begins by reviewing an argument from Special Relativity to the B-theory: because the notion of simultaneity becomes a relative one in Special Relativity, there is no room for the idea of an objective succession of “nows”. He then notes that this argument is disrupted in the context of General Relativity, because in models of the latter theory to date, the presence of matter does allow recovery of an objectively distinguished series of “nows”. Gödel then proposes a new model (Gödel 1949a [1990a]) in which no such recovery is possible. (This is the model that contains CTC’s.) Finally, he addresses the issue of how one can infer anything about the nonexistence of an objective flow of time in our universe from the existence of a merely possible universe in which there is no objectively distinguished series of “nows”. His main response is that while it would not be straightforwardly contradictory to suppose that the existence of an objective flow of time depends on the particular, contingent arrangement and motion of matter in the world, this would nevertheless be unsatisfactory. Responses to Gödel have been of two main kinds. Some have objected to the claim that there is no objective flow of time in his model universe (e.g. Savitt (2005); see also Savitt (1994)). Others have objected to the attempt to transfer conclusions about that model universe to our own universe (e.g. Earman (1995, 197–200); for a partial response to Earman see Belot (2005, §3.4)). [ 28 ]

Earlier we posed two questions:

Gödel’s argument is related to the second question. Let’s turn now to the first question. Godfrey-Smith (1980, 72) writes “The metaphysical picture which underlies time travel talk is that of the block universe [i.e. eternalism, in the terminology of the present entry], in which the world is conceived as extended in time as it is in space.” In his report on the Analysis problem to which Godfrey-Smith’s paper is a response, Harrison (1980, 67) replies that he would like an argument in support of this assertion. Here is an argument: [ 29 ]

A fundamental requirement for the possibility of time travel is the existence of the destination of the journey. That is, a journey into the past or the future would have to presuppose that the past or future were somehow real. (Grey, 1999, 56)

Dowe (2000, 442–5) responds that the destination does not have to exist at the time of departure: it only has to exist at the time of arrival—and this is quite compatible with non-eternalist views. And Keller and Nelson (2001, 338) argue that time travel is compatible with presentism:

There is four-dimensional [i.e. eternalist, in the terminology of the present entry] time-travel if the appropriate sorts of events occur at the appropriate sorts of times; events like people hopping into time-machines and disappearing, people reappearing with the right sorts of memories, and so on. But the presentist can have just the same patterns of events happening at just the same times. Or at least, it can be the case on the presentist model that the right sorts of events will happen, or did happen, or are happening, at the rights sorts of times. If it suffices for four-dimensionalist time-travel that Jennifer disappears in 2054 and appears in 1985 with the right sorts of memories, then why shouldn’t it suffice for presentist time-travel that Jennifer will disappear in 2054, and that she did appear in 1985 with the right sorts of memories?

Sider (2005) responds that there is still a problem reconciling presentism with time travel conceived in Lewis’s way: that conception of time travel requires that personal time is similar to external time—but presentists have trouble allowing this. Further contributions to the debate whether presentism—and other versions of the A-theory—are compatible with time travel include Monton (2003), Daniels (2012), Hall (2014) and Wasserman (2018) on the side of compatibility, and Miller (2005), Slater (2005), Miller (2008), Hales (2010) and Markosian (2020) on the side of incompatibility.

Leibniz’s Law says that if x = y (i.e. x and y are identical—one and the same entity) then x and y have exactly the same properties. There is a superficial conflict between this principle of logic and the fact that things change. If Bill is at one time thin and at another time not so—and yet it is the very same person both times—it looks as though the very same entity (Bill) both possesses and fails to possess the property of being thin. Three-dimensionalists and four-dimensionalists respond to this problem in different ways. According to the four-dimensionalist, what is thin is not Bill (who is a four-dimensional entity) but certain temporal parts of Bill; and what is not thin are other temporal parts of Bill. So there is no single entity that both possesses and fails to possess the property of being thin. Three-dimensionalists have several options. One is to deny that there are such properties as ‘thin’ (simpliciter): there are only temporally relativised properties such as ‘thin at time t ’. In that case, while Bill at t 1 and Bill at t 2 are the very same entity—Bill is wholly present at each time—there is no single property that this one entity both possesses and fails to possess: Bill possesses the property ‘thin at t 1 ’ and lacks the property ‘thin at t 2 ’. [ 30 ]

Now consider the case of a time traveller Ben who encounters his younger self at time t . Suppose that the younger self is thin and the older self not so. The four-dimensionalist can accommodate this scenario easily. Just as before, what we have are two different three-dimensional parts of the same four-dimensional entity, one of which possesses the property ‘thin’ and the other of which does not. The three-dimensionalist, however, faces a problem. Even if we relativise properties to times, we still get the contradiction that Ben possesses the property ‘thin at t ’ and also lacks that very same property. [ 31 ] There are several possible options for the three-dimensionalist here. One is to relativise properties not to external times but to personal times (Horwich, 1975, 434–5); another is to relativise properties to spatial locations as well as to times (or simply to spacetime points). Sider (2001, 101–6) criticises both options (and others besides), concluding that time travel is incompatible with three-dimensionalism. Markosian (2004) responds to Sider’s argument; [ 32 ] Miller (2006) also responds to Sider and argues for the compatibility of time travel and endurantism; Gilmore (2007) seeks to weaken the case against endurantism by constructing analogous arguments against perdurantism. Simon (2005) finds problems with Sider’s arguments, but presents different arguments for the same conclusion; Effingham and Robson (2007) and Benovsky (2011) also offer new arguments for this conclusion. For further discussion see Wasserman (2018) and Effingham (2020). [ 33 ]

We have seen arguments to the conclusions that time travel is impossible, improbable and inexplicable. Here’s an argument to the conclusion that backwards time travel simply will not occur. If backwards time travel is ever going to occur, we would already have seen the time travellers—but we have seen none such. [ 34 ] The argument is a weak one. [ 35 ] For a start, it is perhaps conceivable that time travellers have already visited the Earth [ 36 ] —but even granting that they have not, this is still compatible with the future actuality of backwards time travel. First, it may be that time travel is very expensive, difficult or dangerous—or for some other reason quite rare—and that by the time it is available, our present period of history is insufficiently high on the list of interesting destinations. Second, it may be—and indeed existing proposals in the physics literature have this feature—that backwards time travel works by creating a CTC that lies entirely in the future: in this case, backwards time travel becomes possible after the creation of the CTC, but travel to a time earlier than the time at which the CTC is created is not possible. [ 37 ]

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Paradox-Free Time Travel Is Theoretically Possible, Researchers Say

Matthew S. Schwartz

A dog dressed as Marty McFly from Back to the Future attends the Tompkins Square Halloween Dog Parade in 2015. New research says time travel might be possible without the problems McFly encountered. Timothy A. Clary/AFP via Getty Images hide caption

A dog dressed as Marty McFly from Back to the Future attends the Tompkins Square Halloween Dog Parade in 2015. New research says time travel might be possible without the problems McFly encountered.

"The past is obdurate," Stephen King wrote in his book about a man who goes back in time to prevent the Kennedy assassination. "It doesn't want to be changed."

Turns out, King might have been on to something.

Countless science fiction tales have explored the paradox of what would happen if you went back in time and did something in the past that endangered the future. Perhaps one of the most famous pop culture examples is in Back to the Future , when Marty McFly goes back in time and accidentally stops his parents from meeting, putting his own existence in jeopardy.

But maybe McFly wasn't in much danger after all. According a new paper from researchers at the University of Queensland, even if time travel were possible, the paradox couldn't actually exist.

Researchers ran the numbers and determined that even if you made a change in the past, the timeline would essentially self-correct, ensuring that whatever happened to send you back in time would still happen.

"Say you traveled in time in an attempt to stop COVID-19's patient zero from being exposed to the virus," University of Queensland scientist Fabio Costa told the university's news service .

"However, if you stopped that individual from becoming infected, that would eliminate the motivation for you to go back and stop the pandemic in the first place," said Costa, who co-authored the paper with honors undergraduate student Germain Tobar.

"This is a paradox — an inconsistency that often leads people to think that time travel cannot occur in our universe."

A variation is known as the "grandfather paradox" — in which a time traveler kills their own grandfather, in the process preventing the time traveler's birth.

The logical paradox has given researchers a headache, in part because according to Einstein's theory of general relativity, "closed timelike curves" are possible, theoretically allowing an observer to travel back in time and interact with their past self — potentially endangering their own existence.

But these researchers say that such a paradox wouldn't necessarily exist, because events would adjust themselves.

Take the coronavirus patient zero example. "You might try and stop patient zero from becoming infected, but in doing so, you would catch the virus and become patient zero, or someone else would," Tobar told the university's news service.

In other words, a time traveler could make changes, but the original outcome would still find a way to happen — maybe not the same way it happened in the first timeline but close enough so that the time traveler would still exist and would still be motivated to go back in time.

"No matter what you did, the salient events would just recalibrate around you," Tobar said.

The paper, "Reversible dynamics with closed time-like curves and freedom of choice," was published last week in the peer-reviewed journal Classical and Quantum Gravity . The findings seem consistent with another time travel study published this summer in the peer-reviewed journal Physical Review Letters. That study found that changes made in the past won't drastically alter the future.

Bestselling science fiction author Blake Crouch, who has written extensively about time travel, said the new study seems to support what certain time travel tropes have posited all along.

"The universe is deterministic and attempts to alter Past Event X are destined to be the forces which bring Past Event X into being," Crouch told NPR via email. "So the future can affect the past. Or maybe time is just an illusion. But I guess it's cool that the math checks out."

time travel
grandfather paradox

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Thomas F. Staley: Alchemist and Time Traveler

Thomas F. Staley:

Alchemist and Time Traveler

As the legend goes, an ambitious young professor with a newly minted PhD from Pitt came home to Tulsa with the aim of making what was then the oil capital of the world into an intellectual powerhouse. So, in 1963, he took to his garage and, with the help of a few students, began laying out a modestly sized magazine audaciously titled the James Joyce Quarterly . Thirty-six cheaply set pages were stapled between Kelly green covers and accompanied by a deceptively reserved editorial statement: “The idea of the JJQ grew out of a modestly conceived notion to draw Joyceans together and to publish provocative essays dealing with Joyce’s life, work, and milieu.” Those who knew Tom understood there was nothing modest about this venture at all. It entered into an already crowded field of competing Joyce journals and aimed to make Tulsa rhyme with Dublin, Paris, Zurich, Paris, and Trieste.

Almost 60 years later, the James Joyce Quarterly has become not simply the international journal of record for one of the world’s most influential novelists, but an intellectual touchstone for those interested in modern literature and culture more generally. During Tom’s tenure at the helm, it drew widespread attention for its innovative articles and eager attempts to bring artists, scholars, teachers, novelists, and Joyce’s fans into active dialogue. Seamus Heaney published poems in its pages while painters jostled to have their work appear on its often lavishly illustrated covers. Issues went out to avid readers around the world, and our subscription archive still contains some remarkable surprises, not least among them the renewal cards from John Lennon.

For most of us, this would be enough. The JJQ is a fine and enduring legacy to Tom’s robust vision. It turned out, however, that he was only getting started. Just a few years after publishing that first issue, he founded the International James Joyce Foundation and helped institutionalize haphazard Bloomsday celebrations as juggernaut biennial symposia that moved from one glittering European city to another, their hundreds of participants spending a full week delving into the ever-twisting texts Joyce created. As the current secretary of that Foundation and editor of the JJQ , I can affirm that we all continue to stand on Tom’s broad shoulders, benefitting day after day, year after year from his ambitious drive to cement Joyce into our cultural and intellectual foundations. And yet, the JJQ and the Foundation remain a footnote to a now much larger story.

My first inkling of what Tom was actually doing came in the early 1990s when, as a college student, I stumbled across some copies of the JJQ while trying to make sense of what would remain–for a few more years anyway–my largely decorative copy of Ulysses . The first page of each issue had a small logo with what appeared to be some kind of castle, captioned “University of Tulsa.” That castle, it turned out, was McFarlin Library, the home to what I now think of as Staley’s practice run for his real life’s work. When I later set to work in graduate school on a study of modern literature, that little castle began to loom ever larger. It popped up in footnotes; my professors mentioned it in passing as a place they had visited; and some of my colleagues inexplicably left the Rhode Island seaside for the inferno-like summers of Oklahoma, just so they could explore the treasures of this odd prairie fortress.

Within its walls, it turns out, Staley had been collecting an extraordinary range of letters, manuscripts, artworks, and archives focused almost exclusively on the early twentieth century. Thanks, in part, to his deep roots in the community and keen ability to charm donors, artists, and agents alike, he had engaged in the best kind of alchemy: transforming Tulsa’s vast oil wealth into boxes and boxes of paper. If you haven’t done so, I urge you to take just a passing look at what McFarlin’s Special Collections now hold. Yes, there are acres of Joyce stuff gathered from Harriet Shaw Weaver as well as Paul and Lucie Léon. But you can also find Rebecca West’s detailed accounts of the Nuremberg Trials; the stacks of poems and cartoons that Stevie Smith randomly interwove into her books; and the strange novels and even stranger paintings Anna Kavan created that mix drug use, climate change, and apocalypse. And then there’s the complete life archive of Nobel laureate V. S. Naipaul, Jean Rhys’s Paris notebooks, the nearly 10,000 books and magazines from Cyril Connolly’s library, and the papers of Lynn Riggs, the Cherokee playwright whose Green Grow the Lilacs became Oklahoma! You can even find an alternative ending for John Fowles’ The French Lieutenant’s Woman , or, as was the case shortly after I arrived, perhaps even discover an unpublished Rebecca West novel squirreled away in the boxes.

This list could go on to include paintings by D. H. Lawrence, Henri Matisse, and Pablo Picasso, a sprawling collection of periodicals and comics, perhaps the richest surviving collection of materials on the Tulsa Race Massacre, and all kinds of rare and extraordinary books. And here it all sits just outside my window, rising up above the university green to peer indifferently at the buildings of downtown Tulsa that helped generate all this cultural wealth. Collecting and preserving such treasures is the work of many hands, but it was Tom’s daring that made it possible—the same wildcatting spirit that still defines the city as a whole. From here, of course, Tom would move on to the Harry Ransom Center at the University of Texas, where he tapped an even deeper pool of money to create one of world’s greatest cultural institutions—a marvel made of paper that still has the capacity to evoke shock and wonder alike. Here in Tulsa, Tom began the work that subtly but powerfully shifted the gaze of the intellectual world away from the capitals of Europe and the great libraries of Harvard and Yale toward the vast flatlands running through the middle of the country.

Fortunately, Tom became a colleague and friend whom I got to know a bit near the end of his career. His magnetic personality drew you in, though you knew at the same time others too were constantly attracted to that same invisible field. He could work a room with consummate skill, speaking with a subtly inflected Oklahoma drawl that arrested you with its directness. You got a sense that there was always a deal to be made, a new idea just lurking around the corner, and, yes, a donation to be charmed from your wallet and fed to his alchemical project. He produced capable scholarship early in his career, but that’s not what really matters. Tom wanted, more than anything, to build the institutions that made scholarship possible for others. As a consequence, his extraordinary legacy will live on far beyond his monographs and bibliographies. It will flicker to life decades from now when a young professor’s first article appears in the JJQ or when a diligent scholar opens a document box and discovers a lost text, alternative draft, or revealing letter.

How ultimately do we describe such a legacy? I have heard Tom called a giant, an icon, and even a whirlwind. That’s all true, but such words are too worn by use to capture what made him so singular a figure. For my part, I see him as a time traveler—maybe the only one I’ve ever known. Rarely a man in the moment, he moved effortlessly to the past, which he believed, with relentless optimism, could be transported into the present. And, inexplicably, he could move forward in time as well, seeing what would matter decades or even centuries from now—what work would need to be preserved and what institutions we’d need to make it meaningful. In my two decades at Tulsa, I’ve seen such journeys in time as queer, feminist, and indigenous stories have emerged from the collections at McFarlin that Tom helped build nearly a half-century ago. Like so many others, I’ll miss Tom’s energy, excitement, and keen judgment. But I find genuine solace in knowing that our time-traveling companion will flash by in every issue of the JJQ , in every document box I pull from McFarlin, and in the vast archival treasures that will sustain generations of scholars to come.

By Sean Latham

Editor, James Joyce Quarterly

A pair of hands hold a disintegrating white round clock

Can we time travel? A theoretical physicist provides some answers

Emeritus professor, Physics, Carleton University

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Peter Watson received funding from NSERC. He is affiliated with Carleton University and a member of the Canadian Association of Physicists.

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Time travel makes regular appearances in popular culture, with innumerable time travel storylines in movies, television and literature. But it is a surprisingly old idea: one can argue that the Greek tragedy Oedipus Rex , written by Sophocles over 2,500 years ago, is the first time travel story .

But is time travel in fact possible? Given the popularity of the concept, this is a legitimate question. As a theoretical physicist, I find that there are several possible answers to this question, not all of which are contradictory.

The simplest answer is that time travel cannot be possible because if it was, we would already be doing it. One can argue that it is forbidden by the laws of physics, like the second law of thermodynamics or relativity . There are also technical challenges: it might be possible but would involve vast amounts of energy.

There is also the matter of time-travel paradoxes; we can — hypothetically — resolve these if free will is an illusion, if many worlds exist or if the past can only be witnessed but not experienced. Perhaps time travel is impossible simply because time must flow in a linear manner and we have no control over it, or perhaps time is an illusion and time travel is irrelevant.

a woman stands among a crowd of people moving around her

Laws of physics

Since Albert Einstein’s theory of relativity — which describes the nature of time, space and gravity — is our most profound theory of time, we would like to think that time travel is forbidden by relativity. Unfortunately, one of his colleagues from the Institute for Advanced Study, Kurt Gödel, invented a universe in which time travel was not just possible, but the past and future were inextricably tangled.

We can actually design time machines , but most of these (in principle) successful proposals require negative energy , or negative mass, which does not seem to exist in our universe. If you drop a tennis ball of negative mass, it will fall upwards. This argument is rather unsatisfactory, since it explains why we cannot time travel in practice only by involving another idea — that of negative energy or mass — that we do not really understand.

Mathematical physicist Frank Tipler conceptualized a time machine that does not involve negative mass, but requires more energy than exists in the universe .

Time travel also violates the second law of thermodynamics , which states that entropy or randomness must always increase. Time can only move in one direction — in other words, you cannot unscramble an egg. More specifically, by travelling into the past we are going from now (a high entropy state) into the past, which must have lower entropy.

This argument originated with the English cosmologist Arthur Eddington , and is at best incomplete. Perhaps it stops you travelling into the past, but it says nothing about time travel into the future. In practice, it is just as hard for me to travel to next Thursday as it is to travel to last Thursday.

Resolving paradoxes

There is no doubt that if we could time travel freely, we run into the paradoxes. The best known is the “ grandfather paradox ”: one could hypothetically use a time machine to travel to the past and murder their grandfather before their father’s conception, thereby eliminating the possibility of their own birth. Logically, you cannot both exist and not exist.

Read more: Time travel could be possible, but only with parallel timelines

Kurt Vonnegut’s anti-war novel Slaughterhouse-Five , published in 1969, describes how to evade the grandfather paradox. If free will simply does not exist, it is not possible to kill one’s grandfather in the past, since he was not killed in the past. The novel’s protagonist, Billy Pilgrim, can only travel to other points on his world line (the timeline he exists in), but not to any other point in space-time, so he could not even contemplate killing his grandfather.

The universe in Slaughterhouse-Five is consistent with everything we know. The second law of thermodynamics works perfectly well within it and there is no conflict with relativity. But it is inconsistent with some things we believe in, like free will — you can observe the past, like watching a movie, but you cannot interfere with the actions of people in it.

Could we allow for actual modifications of the past, so that we could go back and murder our grandfather — or Hitler ? There are several multiverse theories that suppose that there are many timelines for different universes. This is also an old idea: in Charles Dickens’ A Christmas Carol , Ebeneezer Scrooge experiences two alternative timelines, one of which leads to a shameful death and the other to happiness.

Time is a river

Roman emperor Marcus Aurelius wrote that:

“ Time is like a river made up of the events which happen , and a violent stream; for as soon as a thing has been seen, it is carried away, and another comes in its place, and this will be carried away too.”

We can imagine that time does flow past every point in the universe, like a river around a rock. But it is difficult to make the idea precise. A flow is a rate of change — the flow of a river is the amount of water that passes a specific length in a given time. Hence if time is a flow, it is at the rate of one second per second, which is not a very useful insight.

Theoretical physicist Stephen Hawking suggested that a “ chronology protection conjecture ” must exist, an as-yet-unknown physical principle that forbids time travel. Hawking’s concept originates from the idea that we cannot know what goes on inside a black hole, because we cannot get information out of it. But this argument is redundant: we cannot time travel because we cannot time travel!

Researchers are investigating a more fundamental theory, where time and space “emerge” from something else. This is referred to as quantum gravity , but unfortunately it does not exist yet.

So is time travel possible? Probably not, but we don’t know for sure!

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The Route of Santiago in The Alchemist

There are very few stories that echo throughout generations to come. “The Alchemist” by Paulo Coelho is a tale of wanderlust, resilience, self-discovery, and finding true love. It is the journey of a young boy named Santiago who has the courage to follow his dreams.

While many of us wait for things to get right before we start traveling, this boy embarks on an epic adventure, beats all odds, and finds his treasure. Are you ready to follow your heart?

“People are capable, at any time in their lives of doing what they dream of.” ~ The Alchemist

The Route Of Santiago Alchemist

Santiago’s journey is not only a spiritual discovery of his potential but also a travel saga. He covers three countries in his wake. He crosses Spain , Morocco , and Egypt to get to his destination.

As it is indeed said, “It is not the destination that matters, but the journey.” Let us now give you a glance of the journey that Santiago takes in The Alchemist.

ANDALUSIA, SPAIN

This young boy gave up a sheltered life of family to become a humble shepherd, just because he wanted to see the world. In a cold night, he lies in an abandoned church, with is sheep. Besides him is a sycamore tree whose significant role reveals at the end.

He is now in a part of Andalusia, guiding his sheep through pastures and finding the water in the warm temperate region. It is in the dilapidated church that he has dreamed of his treasure. Now, he embarks on his journey.

TARIFA, SPAIN

Santiago comes to Tarifa to sell his sheep’s wool. He wants to test his fate. So, he goes to a gypsy fortune teller. She tells him about his dream of treasure near pyramids and asks him to follow it.

The gypsy strikes a deal with him, that if he finds his treasure, he should share it with her.

Another encounter is due to the Old King. Paulo Coelho draws the similarity from High Priest in the Bible to the Old King in the novel.

He has a breastplate which has glittering stones of Urim (good) and Thummim (bad). The king lends him the stones which will guide his path as omens.

TANGIER, MOROCCO

Sadly, the boy’s money gets stolen. He does not have the means to make his journey to the pyramids. So he stays back at the mountain, working for the glass merchant. He saves all the money from work, planning on buying sheep.

After betrayal from the world, he does not want to follow his dream. But when he has enough money to buy sheep, he sees the stones which the King gave him. He again sets forth on his journey from Morocco to Egypt .

Nobody knows, which Oasis Santiago stays at during his journey. We do know however that the Oasis mentioned here is either in Morocco or in Egypt.

One of the important twist in the story takes place here. Here, Santiago meets the Alchemist who inducts him to the universal language. From here he sets forth with confidence and his next stop awaits another great move.

AL PAYOUM, EGYPT

Finally, when he reaches the land of Pyramids , he meets the love of his life. In this desert, Santiago finds a kindred soul who encourages him to follow his dreams. Despite his heart’s dilemma, he goes ahead on his journey promising to come back.

THE DESERT, EGYPT

On his way to The Pyramids Santiago does something legendary. When he and the Alchemist are in clutches of the kidnappers, the Alchemist promises that the boy can turn himself into the wind.

The universal language now culminates in the boy’s soul. He turns to the wind and communicates with all natural elements.

THE PYRAMIDS, EGYPT

His ultimate destination is the Pyramids. In his dreams, a big Pyramid was his treasure home.

He digs and digs but finds nothing in the sands. When he meets a man, who exchanges Gold for Santiago’s life, then Santiago realizes that his treasure was in the Old ruined church beside the Sycamore tree.

THE OLD RUINED CHURCH

In the last scene, we see Santiago digging his treasure under the dark blue sky of night. He chides the wind for not telling him the secret. But it was the journey that should matter to all travelers like it did to Santiago.

Do not wait for a fat bank account or winning a lottery. Imagine like a child, and embark on your dream journey. An adventurous journey has transformation power.

Once you begin, everything will start coming together. As it says in the Alchemist, once you set your heart on a particular mission, the whole universe will conspire together to help you achieve what you seek.

Bon Voyage!

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November 13, 2017 10:48 am Published by Staff Writer 1 Comment

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The Best Fictional Characters Who Time Travel

Time travel is an extremely interesting subject in fiction because it deals with a myriad of themes and issues. Traveling in time allows fictional characters to deal with history, the future, or both with modern day characters. Characters who time travel range from average Joes who stumbled into time travel, to hundred year old aliens who love to move through time and space.

The charm of some time traveling fiction is to see how characters deal with an unfamiliar era. Marty McFly dealt with his parents in high school, while Austin Powers traveled from the 60s to the 90s and had to abandon some of his 60s-ways. Not all time travel is used for innocent purposes. In the Terminator series, killer cyborgs used time travel to murder people and change the future.

Some time travelers use a time machine or spaceship, while others time travel by accident. While The Doctor use his Tardis to see the universe, Peggy Sue’s concussion allowed her to go travel back in time to her high school days.

Ash Williams

Ash is a groovy guy who finds himself time-traveling through some seriously strange situations. He's got a chainsaw for a hand and a boomstick in his holster, which definitely comes in handy when battling evil deadites across different eras. But let me tell you, he's always scratching his head, wondering how he ended up in medieval times or the Wild West. Ash may not be the brightest bulb in the box, but he's got enough guts and one-liners to make any time travel adventure a blast.

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Marty McFly

Marty is a teenager who accidentally travels back in time in a DeLorean car invented by his eccentric friend, Doc Brown. He finds himself in the 1950s and must navigate the challenges of altering history while trying to get back to his own time. Marty is courageous and quick-witted, but also struggles with the consequences of his actions.

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Emmett Brown

Known as Doc Brown, he is a brilliant scientist who invents the time-traveling DeLorean. Doc is eccentric and often gets caught up in his own experiments, but he is also a loyal friend to Marty. He has a deep fascination with time travel and is constantly seeking new adventures through different eras.

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A mysterious and enigmatic character from the long-running British TV show Doctor Who , the Doctor is an alien Time Lord who can regenerate into a new form when near death. With their trusty TARDIS (a time-traveling spaceship), the Doctor explores different times and places, always seeking to right wrongs and protect the universe from various threats.

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Terminator (T-101)

A cyborg assassin sent back in time from a post-apocalyptic future, the T-101 is programmed to kill Sarah Connor, the mother of humanity's future savior. However, it eventually develops a sense of morality and protects Sarah and her son John instead. The T-101 is relentless and unstoppable, making it a formidable force throughout its time-traveling journey.

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A mischievous god from Norse mythology, Loki possesses the ability to manipulate time and space. He often uses this power for his own amusement or personal gain, causing chaos wherever he goes. Despite his villainous tendencies, Loki also displays moments of complexity and vulnerability that make him a compelling character.

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Spock, the logical and stoic Vulcan from Star Trek , may not be primarily associated with time travel, but he has encountered various temporal anomalies throughout his journeys aboard the USS Enterprise. Known for his calm demeanor and superior intellect, Spock brings a sense of rationality to the chaos of time-traveling situations. His ability to analyze complex situations adds depth to his character as he grapples with the intricacies of altering timelines.

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Bill S. Preston, Esq.

Bill is one half of the dynamic duo known as Bill & Ted, who embark on a series of time-traveling escapades in their iconic phone booth. With his laid-back attitude and infectious enthusiasm, Bill brings a sense of comedic relief to their journeys through history. Despite their initial bumbling nature, Bill's unwavering friendship and dedication to their mission make him an essential part of their time-traveling adventures.

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A pizza delivery boy who accidentally gets cryogenically frozen and wakes up in the year 3000, Fry becomes a time traveler by virtue of being displaced in time. He joins a delivery crew and embarks on various adventures throughout different eras, often struggling to adapt to the future while also longing for his past life.

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Hermione Granger

A highly intelligent and resourceful witch from the Harry Potter series, Hermione uses a Time-Turner to attend multiple classes at once. She is diligent and determined, always seeking knowledge and using her abilities to help her friends. However, she also learns about the dangers of meddling with time and the importance of accepting its limitations.

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Sam Beckett

Sam Beckett is the main character in the TV series Quantum Leap , where he finds himself leaping into different people's bodies throughout history. As a physicist who becomes trapped in his own time-travel experiment, Sam's mission is to right historical wrongs and find his way back home. His determination and empathy for others make him a relatable and engaging character as he leaps through time.

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Ted "Theodore" Logan

One half of the iconic duo known as Bill & Ted, Ted is a laid-back and somewhat dim-witted teenager who, along with his best friend Bill, travels through time to complete a history project. Ted's journey through time helps him grow into a more responsible and thoughtful individual.

Jean-Luc Picard

Jean-Luc Picard is the distinguished captain of the USS Enterprise in Star Trek: The Next Generation . While not primarily associated with time travel, Picard encounters temporal anomalies during his missions, showcasing his calm leadership and intellectual prowess in unraveling complex temporal puzzles. His diplomatic nature and moral compass make him an engaging character as he faces the challenges presented by time-traveling phenomena.

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Amy Pond is another beloved companion of the Doctor in the Doctor Who series. With her fiery personality and strong-willed nature, Amy brings a sense of adventure to their time-traveling escapades. Her emotional journey and deep connection with the Doctor create a captivating storyline as she explores different eras and confronts her own personal demons.

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Jack Harkness

Jack Harkness is a charming and immortal time-traveler from the Doctor Who universe. With his dashing good looks and flirtatious nature, Jack adds a touch of excitement to any time-traveling adventure. His complex backstory and mysterious past make him an intriguing character as he navigates through different eras, often finding himself caught in the midst of dangerous situations.

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River Song is a captivating character from the Doctor Who series, known for her complex relationship with the Doctor and her own time-traveling abilities. With her sharp wit and enigmatic personality, River adds an air of mystery to any storyline she appears in. Her nonlinear timeline and deep connection to the Doctor create a compelling narrative as she navigates through time alongside him.

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Rory Williams

Rory is a loyal companion of the Doctor in the Doctor Who series. With his unwavering dedication and courage, Rory adds a sense of stability to their time-traveling adventures. Despite being initially portrayed as an ordinary human, Rory's character evolves throughout the series, showcasing resilience and bravery as he faces various challenges across different timelines.

Alan Parrish

Alan Parrish is the protagonist of the film Jumanji , where he becomes trapped in a magical board game that transports him through time and dangerous adventures. As a young boy who grows up in the jungle after being sucked into the game, Alan's resilience and resourcefulness make him a relatable character as he tries to find a way back home while facing various challenges across different time periods.

Rose Tyler is a beloved companion of the Doctor in the Doctor Who series. With her down-to-earth personality and unwavering loyalty, Rose brings a sense of humanity to their time-traveling escapades. Her emotional journey and deep connection with the Doctor create a captivating storyline as she explores different eras and faces the consequences of altering history.

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Sarah Jane Smith

Sarah Jane Smith is a resourceful journalist and companion of the Doctor in the Doctor Who series. With her tenacity and investigative skills, Sarah Jane adds a sense of determination to their time-traveling adventures. Her strong bond with the Doctor and her own personal growth make her a compelling character as she faces various challenges across different eras.

Agent Phil Coulson

Agent Phil Coulson is a beloved character from the Marvel Cinematic Universe, known for his role in the organization S.H.I.E.L.D. While not primarily associated with time travel, Coulson encounters temporal anomalies and alternate timelines throughout his missions. His dry wit and unwavering dedication to protecting humanity make him an engaging character as he navigates through the complexities of time-altering events.

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Ant-Man (Scott Lang)

Scott Lang gains the ability to shrink in size and increase in strength thanks to a special suit created by Dr. Hank Pym. With this newfound power, he becomes Ant-Man and embarks on various adventures, including traveling through time to prevent catastrophic events. Scott is witty and relatable, often finding himself in humorous situations due to his unique abilities.

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Kyle Reese is a soldier sent back in time from a post-apocalyptic future in the Terminator franchise. Tasked with protecting Sarah Connor, the mother of humanity's future savior, Kyle finds himself caught in a battle against powerful machines. His bravery and selflessness make him a compelling character as he confronts the challenges of altering history while trying to ensure humanity's survival.

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Okabe Rintarou

The main protagonist of the anime series Steins;Gate , Okabe is a self-proclaimed mad scientist who accidentally discovers a way to send text messages back in time. As he delves deeper into time travel experiments , Okabe faces numerous challenges and grapples with the consequences of altering events. He is eccentric yet compassionate, making him an intriguing character to follow.

Merlin, the legendary wizard from Arthurian mythology, possesses magical abilities that allow him to manipulate time and space. With his wisdom and foresight, Merlin often guides and advises the legendary King Arthur on his quests. His mysterious nature and deep connection to ancient magic create an aura of intrigue as he weaves through different timelines.

Mister Peabody

Mister Peabody is a highly intelligent dog who possesses a time machine known as the WABAC. Alongside his adopted human son, Sherman, Mister Peabody embarks on educational and humorous adventures throughout history. His dry wit and vast knowledge make him an entertaining character as he navigates through different time periods, imparting wisdom and solving problems along the way.

The T-1000 is a shape-shifting android assassin from the Terminator franchise, sent back in time to eliminate key targets. With its liquid metal form and advanced technology, this relentless machine seems unstoppable. However, as it pursues its targets across different time periods, the T-1000 encounters unexpected obstacles and paradoxes that leave it momentarily perplexed. But don't be fooled, this time-traveling killing machine always finds a way to adapt and continue its mission.

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The Time Traveller

As the name suggests, the Time Traveller is a mysterious figure who journeys through time with his trusty time machine. Armed with his scientific knowledge and insatiable curiosity, he explores the past, present, and future, encountering strange civilizations and mind-bending phenomena along the way. Yet, despite his vast experience in time travel, the Time Traveller remains fascinated by the enigmatic nature of temporal mechanics, constantly seeking answers to the mysteries of the universe.

The mighty God of Thunder himself, Thor, is no stranger to epic adventures across time and space. Armed with his trusty hammer Mjolnir, he travels through different eras like a lightning bolt on steroids. But despite his godly powers, Thor often finds himself perplexed by the intricacies of time travel. As he battles ancient foes and encounters historical figures, he can't help but marvel at the wonders and complexities of the temporal realm.

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Cable, also known as Nathan Summers, is a time-traveling mutant from the X-Men universe. With his cybernetic enhancements and ability to manipulate technology, Cable journeys through time to prevent a dystopian future. His gruff demeanor and complex backstory make him a compelling character as he battles against formidable enemies while trying to alter the course of history.

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As they say in well-written scripts, "You mean... like time travel?" + also a few bizarre stories about real people who have claimed, despite every law of physics, they have traveled through time.

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Books & Arts
Published: 30 October 2013

Physics: The time lord and fellow travellers

Andrew Jaffe 1

Nature volume 502 , pages 620–621 ( 2013 ) Cite this article

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As television's time-bending Doctor Who turns 50, Andrew Jaffe explores time travel in fiction and science.

In 1963, an extraterrestrial burst from his time machine and onto British television screens to the strains of a deliciously eerie electronic theme tune, courtesy of the BBC's pioneering Radiophonic Workshop. Doctor Who was born. The series' doughty and eccentric time lord has been zipping from past to future ever since in his TARDIS (Time and Relative Dimension in Space). Regenerated 11 times by new actors — including the latest, Peter Capaldi — the Doctor is going stronger than ever since the show's 2005 reboot.

Generations of fans in numerous countries have fallen for his world-saving, time-hopping antics. But in much science fiction the possibilities of time travel are taken more seriously: its creators try to build a coherent set of rules. Because once you allow the capacity to change past or future, in the real world or in fiction, anything seems possible. For more than a century, time travel has been a rich vein for science-fiction writers and even some scientists — especially those willing to travel farthest from the known laws of physics.

Robert Heinlein's short story “—All You Zombies—” is noted for its rigorous internal logic: all the main characters are the same individual at different times in his/her subjective life. The character travels back and forth through time, changing sex and becoming both of his own parents. In a sense, the story is completely self-consistent: cause and effect seem to be preserved, from the protagonist's point of view; life progresses, albeit with science-fictional sex changes and time travel. But something — that is, someone — has been created from nothing, seemingly violating the local laws of physics (and biology).

Amazingly, this kind of time travel is not obviously forbidden by the laws of physics on a global scale. Einstein's general theory of relativity allows 'closed timelike curves' in which a particle can travel back to the same space-time event at which it began. Travelling along such a curve, everything seems fine. But to other observers, something or someone seems just to pop into and out of existence.

This makes physicists very uncomfortable, so theoretical physicist Igor Novikov and collaborators proposed a 'self-consistency principle' in which time travel is possible. Such a trip must be free of paradoxes, and have a single, coherent four-dimensional view of space and time: travel into the past can happen only if it occurred in the Universe's past! Mathematically, we would lose the ability to make predictions in such a Universe, or parts of it: we don't have enough information about the future to know whether a time traveller will emerge in the present. (This also makes physicists very uncomfortable.)

The US television series Lost codified the self-consistency principle as 'Whatever Happened, Happened': even an atomic bomb exploded by the castaways cannot change the past and bring them home. The 1995 film 12 Monkeys (or its 1962 progenitor La Jetée ) similarly plays with the chronology of a single event: a character sees himself release an apocalyptic virus and usher in the very future he was sent back in time to prevent.

But maybe time travel can occur in other ways; perhaps it is possible to change the past after all. The Star Trek episode 'City on the Edge of Forever' has Dr McCoy travelling back in time to Depression-era America. There he saves the life of a woman, thus changing the future so that the Enterprise is never built. So Kirk and Spock travel back in time and change the past, to save the present, at the price of annihilating the woman with whom Kirk has fallen in love.

In Charles Stross's 2009 sci-fi novella Palimpsests (much influenced by Isaac Asimov's The End of Eternity and 1930s sci-fi pioneer Olaf Stapledon's grander cosmic visions), each intervention in the past revises present and future. In this scenario, when you kill your ancestor, the Universe becomes one in which you were never born. So you never went back in time, so you didn't kill your ancestor, so you were born, so you were able to travel through time, so you did kill your ancestor, so .... Stross makes a virtue of this: the initiation into his Stasis, a sort of universal time-police, is to go back and kill your own grandfather.

The other change-the-past trope is to make today's world a better place by getting rid of some of its more evil past denizens — Desmond Warzel's short story Wikihistory ( go.nature.com/txib8y ) is the funniest version of this I've seen: newbie time travellers keep killing Hitler, so the gurus have to go back and fix the past each time. Or perhaps each intervention cleaves off a new Universe, as in the so-called many-worlds interpretation of quantum mechanics (itself a rich source of scientific and science-fictional ideas, as discussed previously in these pages; go.nature.com/f3oz9w ). Indeed, it seems that understanding the possible (or impossible) physics of time travel will require a full understanding of the 'theory of everything', marrying general relativity and quantum mechanics.

In any scenario, it seems impossible to have time travel without paradoxes or violations of physical laws. So some physicists have theorized that a corollary to the fundamental laws may be that time travel is effectively impossible. In some varieties of the principle, any time machine is censored, hidden inside a black hole formed as a side effect to its creation, walled off from the rest of the Universe by an event horizon. Stephen Hawking has come up with a stronger version, the 'chronology protection conjecture': the laws of physics, relativistic and quantum-mechanical, conspire to prevent time machines' construction (or natural occurrence) in the first place.

Some take a more nuanced, if less physically plausible, approach. Stephen King's book 11/22/63 is premised on attempts to change the history of the day on which President John F. Kennedy was shot. “There's a kind of a rule that you'd express as a ratio,” King told Wired magazine. “The more potential a given event has to change the future, the more difficult that event would be to change.” But not all fictional time travel needs to involve material bodies and the problem of causality. In Kurt Vonnegut's Slaughterhouse-Five , it is Billy Pilgrim's consciousness that has “come unstuck in time” and travels between upstate New York, the planet Tralfamadore and the firebombed city of Dresden.

More than a century ago, writers were already using time travel for dramatic ends. Mark Twain's A Connecticut Yankee in King Arthur's Court skewers the American technophiles of the 1880s as much as the early-medieval Brits whose world he enters. And H. G. Wells's The Time Machine is a polemic on the social stratification of late-Victorian Britain, couched in the language of extra dimensions that would inform Einstein's relativistic merger of space and time in the following decades.

In 1899, the playwright Alfred Jarry leapt off from Wells's ideas to make time travel part of his knowingly absurd 'pataphysics', in his pamphlet Commentary and Instructions for the Practical Construction of the Time Machine . As part of the Beyond Entropy project with the Architectural Association in London, architect Shin Egashira and I tried to realize some of Jarry's machine. Alas, our success, if any, was aesthetic rather than technological.

And then, of course, there is the time lord himself. Paradoxes rarely trouble the Doctor. Time travel serves mostly as a plot device allowing him to visit humans (much easier on the special-effects budget than aliens) in different circumstances, from the recognizable past to the distant future, defeating his enemies again and again. More recently, however, the show has attempted some sort of cross-temporal continuity, even when this means retroactively changing the past and future to bring his nemeses, the Daleks, back from the dead.

The creators of Doctor Who have tended to favour thrills and chills over scientific (or pseudoscientific) precision. But they have also inspired millions to ponder profound questions about the nature of space and time and our movements through them. Here's to the next 50 years.

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Jaffe, A. Physics: The time lord and fellow travellers. Nature 502 , 620–621 (2013). https://doi.org/10.1038/502620a

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Published : 30 October 2013

Issue Date : 31 October 2013

DOI : https://doi.org/10.1038/502620a

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The Alchemist

Paulo coelho, ask litcharts ai: the answer to your questions.

The Pursuit of Your Personal Legend Theme Icon

After Santiago arrives in the desert during his pursuit of his Personal Legend, he begins to realize that there is a universal language spoken by all humans, animals, and objects. He learns to speak to the sun and the wind by listening to the desert and by listening to his heart , which can speak the Language of the World. This Language allows him to access “The Soul of The World,” which is a God-like oneness of all things. The novel’s portrayal of a universal language and The Soul of The World demonstrates its theme of the interconnectedness of all things.

Santiago feels a great sense of unity with other people, places, and objects he encounters on his quest, and his ability to access this feeling of unity allows him to learn about the world. For example, the alchemist challenges Santiago to find life in the desert, and Santiago realizes that he does not need advanced skills to do this. He realizes that the interconnectedness of all things allows his horse to be aware of the world, and that life attracts life. He lets his horse lead him to rocks where a snake lives.

The alchemist, an unsurprisingly important figure in the novel given its title, nevertheless does not teach Santiago the literal practices of alchemy in which metals are processed and transformed into gold. But he does help Santiago see that the processes of alchemy, such as purifying and simplifying or observing something to learn from it, are applicable to all of life. For example, Santiago learns from the alchemist that studying the world will teach him everything he needs to know, just as studying the Englishman ’s texts might have taught him the particulars of alchemy. Because of the interconnectedness of all things, the world itself is a great teacher. Any one thing, no matter how small, allows access to the entirety of creation. A metal can access and become gold because of this oneness, and Santiago can transform himself into the wind because of this oneness. The novel portrays tapping into the interconnectedness of things as the goal of both alchemy and the pursuit of one’s Personal Legend.

The Interconnectedness of All Things ThemeTracker

The Interconnectedness of All Things Quotes in The Alchemist

“You came so that you could learn about your dreams,” said the old woman.

“And dreams are the language of God. When he speaks in our language, I

can interpret what he has said. But if he speaks in the language of the soul,

it is only you who can understand.”

“In order to find the treasure, you will have to follow the omens. God has prepared a path for everyone to follow. You just have to read the omens that he left for you.”

Once again he saw that, in that strange land, he was applying the same lessons he had learned with his sheep. “All things are one,” the old man had said.

“Hunches,” his mother used to call them. The boy was beginning to understand that intuition is really a sudden immersion of the soul into the universal current of life, where the histories of all people are connected, and we are able to know everything, because it's all written there. “ Maktub ,” the boy said, remembering the crystal merchant.

“We are afraid of losing what we have, whether it’s our life or our possessions and property. But this fear evaporates when we understand that our life stories and the history of the world were written by the same hand.”

The Unimportance of Death and Fear Theme Icon

“I learned that the world has a soul, and that whoever understands that soul can also understand the language of things. I learned that many alchemists realized their destinies, and wound up discovering the Soul of the World, the Philosopher's Stone, and the Elixir of Life. But, above all, I learned that these things are all so simple that they could be written on the surface of an emerald.”

Alchemy and the Value of Simplicity Theme Icon

At that moment, it seemed to him that time stood still, and the Soul of the World surged within him. When he looked into her dark eyes, and saw that her lips were poised between a laugh and silence, he learned the most important part of the language that all the world spoke—the language that everyone on earth was capable of understanding in their heart. It was love. Something older than humanity, more ancient than the desert. Something that exerted the same force whenever two pairs of eyes met, as had theirs here at the well. She smiled, and that was certainly an omen—the omen he had been awaiting, without even knowing he was, for all his life. The omen he had sought to find with his sheep and in his books, in the crystals and in the silence of the desert.

“And I am a part of your dream, a part of your destiny, as you call it. That’s why I want you to continue toward your goal. If you have to wait until the war is over, then wait. But if you have to go before then, go on in pursuit of your dream. The dunes are changed by the wind, but the desert never changes. That’s the way it will be with our love for each other…Maktub,” she said. “If I am really a part of your dream, you'll come back one day.”

The camel driver understood what the boy was saying. He knew that any given thing on the face of the earth could reveal the history of all things. One could open a book to any page, or look at a person’s hand; one could turn a card, or watch the flight of the birds… whatever the thing observed, one could find a connection with his experience of the moment. Actually, it wasn’t that those things, in themselves, revealed anything at all; it was just that people, looking at what was occurring around them, could find a means of penetration to the Soul of the World.

But that the hand had a reason for all of this, and that only the hand could perform miracles, or transform the sea into a desert…or a man into the wind. Because only the hand understood that it was a larger design that had moved the universe to the point at which six days of creation had evolved into a Master Work. The boy reached through to the Soul of the World, and saw that it was a part of the Soul of God. And he saw that the Soul of God was his own soul. And that he, a boy, could perform miracles.

“You’re not going to die. You’ll live, and you’ll learn that a man shouldn’t be so stupid. Two years ago, right here on this spot, I had a recurrent dream, too. I dreamed that I should travel to the fields of Spain and look for a ruined church where shepherds and their sheep slept. In my dream, there was a sycamore growing out of the ruins of the sacristy, and I was told that, if I dug at the roots of the sycamore, I would find a hidden treasure. But I’m not so stupid as to cross an entire desert just because of a recurrent dream.”

The wind began to blow again. It was the levanter, the wind that came from Africa. It didn’t bring with it the smell of the desert, nor the threat of Moorish invasion. Instead, it brought the scent of a perfume he knew well, and the touch of a kiss—a kiss that came from far away, slowly, slowly, until it rested on his lips. The boy smiled. It was the first time she had done that. “I’m coming, Fatima,” he said.

Is Time Travel Possible?

We all travel in time! We travel one year in time between birthdays, for example. And we are all traveling in time at approximately the same speed: 1 second per second.

We typically experience time at one second per second. Credit: NASA/JPL-Caltech

NASA's space telescopes also give us a way to look back in time. Telescopes help us see stars and galaxies that are very far away . It takes a long time for the light from faraway galaxies to reach us. So, when we look into the sky with a telescope, we are seeing what those stars and galaxies looked like a very long time ago.

However, when we think of the phrase "time travel," we are usually thinking of traveling faster than 1 second per second. That kind of time travel sounds like something you'd only see in movies or science fiction books. Could it be real? Science says yes!

Image of galaxies, taken by the Hubble Space Telescope.

This image from the Hubble Space Telescope shows galaxies that are very far away as they existed a very long time ago. Credit: NASA, ESA and R. Thompson (Univ. Arizona)

How do we know that time travel is possible?

More than 100 years ago, a famous scientist named Albert Einstein came up with an idea about how time works. He called it relativity. This theory says that time and space are linked together. Einstein also said our universe has a speed limit: nothing can travel faster than the speed of light (186,000 miles per second).

Einstein's theory of relativity says that space and time are linked together. Credit: NASA/JPL-Caltech

What does this mean for time travel? Well, according to this theory, the faster you travel, the slower you experience time. Scientists have done some experiments to show that this is true.

For example, there was an experiment that used two clocks set to the exact same time. One clock stayed on Earth, while the other flew in an airplane (going in the same direction Earth rotates).

After the airplane flew around the world, scientists compared the two clocks. The clock on the fast-moving airplane was slightly behind the clock on the ground. So, the clock on the airplane was traveling slightly slower in time than 1 second per second.

Credit: NASA/JPL-Caltech

Can we use time travel in everyday life?

We can't use a time machine to travel hundreds of years into the past or future. That kind of time travel only happens in books and movies. But the math of time travel does affect the things we use every day.

For example, we use GPS satellites to help us figure out how to get to new places. (Check out our video about how GPS satellites work .) NASA scientists also use a high-accuracy version of GPS to keep track of where satellites are in space. But did you know that GPS relies on time-travel calculations to help you get around town?

GPS satellites orbit around Earth very quickly at about 8,700 miles (14,000 kilometers) per hour. This slows down GPS satellite clocks by a small fraction of a second (similar to the airplane example above).

Illustration of GPS satellites orbiting around Earth

GPS satellites orbit around Earth at about 8,700 miles (14,000 kilometers) per hour. Credit: GPS.gov

However, the satellites are also orbiting Earth about 12,550 miles (20,200 km) above the surface. This actually speeds up GPS satellite clocks by a slighter larger fraction of a second.

Here's how: Einstein's theory also says that gravity curves space and time, causing the passage of time to slow down. High up where the satellites orbit, Earth's gravity is much weaker. This causes the clocks on GPS satellites to run faster than clocks on the ground.

The combined result is that the clocks on GPS satellites experience time at a rate slightly faster than 1 second per second. Luckily, scientists can use math to correct these differences in time.

Illustration of a hand holding a phone with a maps application active.

If scientists didn't correct the GPS clocks, there would be big problems. GPS satellites wouldn't be able to correctly calculate their position or yours. The errors would add up to a few miles each day, which is a big deal. GPS maps might think your home is nowhere near where it actually is!

In Summary:

Yes, time travel is indeed a real thing. But it's not quite what you've probably seen in the movies. Under certain conditions, it is possible to experience time passing at a different rate than 1 second per second. And there are important reasons why we need to understand this real-world form of time travel.

If you liked this, you may like:

The Travelling Alchemist

Monday, april 22, 2024, using a flow chart for dungeon maps, quickie today.

I've been running Starfinder recently, and with the final session coming up I needed to prepare the ship the party would be stealing from. However I knew I didn't need a highly detailed, highly time consuming map of the ship, but I also didn't want to run it entirely off the cuff. I was inspired by the idea of Point Crawls, so I ended up going with a flowchart map, as seen below:

Ease of Use: While not as rigid as a standard square grid map, it also isn't so loose that the players and the GM can still use it for reference.
Room to Expand: The areas and passages give an idea of how everything connects, but leaves room for improvisation at the table. How it connects can be left up to GM Fiat. For example the connection between the Living area and Maintenance might be an elevator, a staircase, or a series of floors that transition between the two depending on what the GM and Players need at the table.
Ease of Creation: I made this map in about an hour using app.diagrams.net . It's a free browser program than links right into Google Drive.

Monday, January 29, 2024

Yet another maneuver system for osr style games.

Long time no see!

Something I noticed a few days ago that has been bugging me to no end is how in Trad games, mainly D&D, there seems to be a problem with fights that are stagnant. The fighter rocks up to the opposing Orc and they stand there fighting until either one of them is dead or retreating. Compare this to all the best sword fights in movies you've seen. I'll link the famous Princess Bride duel, though doubtless you've seen it.

Look at the way they move around the battlefield, all while remaining engaged with each other. I want to replicate this in my combats. I have devised a system to solve my problems, inspired by Trespasser , Dungeon Crawl Classics , and Mythras . While designing I had these design principles:

2. Rewards the use of maneuvers

3. Encourages movement around the battlefield between those in melee

4. Does not significantly slow combat

Without further ado here are the rules, with design commentary at the bottom.

Strong Hits:

When you hit an enemies armor class or above and your die roll is even, you can confer extra benefits on top of your damage roll. Choose one:

Add +1 damage to the damage roll
Control the battle: Go on the offensive and move the battle somewhere else on the battlefield within reason.
Attempt a maneuver: name a maneuver you would like to attempt that your GM agrees to. Then roll the attack dice again, if you succeed, the maneuver works. Eg. Knock a sword out of someone's hand, kick them off a cliff, etc.
Disengage: Move away from the enemy combatant, this does not provoke an attack of opportunity.*

First, why the decision to make strong hits on a hit + even dice roll? For this I can thank Trespasser for the inspiration, where even dice rolls confer additional effects. I like this because it means these effects are going off 50% of the time an attacker succeeds, which means they happen often but cannot fully be relied upon.

The simple +1 damage is a back up plan, for when there is nowhere useful to move to and no maneuver an attack wants to use. It is only 1 damage because I want to encourage the use of the other options. It is also an easy option for most unintelligent monsters to pick.
This was the inspiration for the whole subsystem. By controlling the battle you can position yourself into an advantageous position or your enemy into a perilous one. For example jumping up onto a rock to gain the high ground, or inching an enemies back up against the edge of a cliff.
These are pretty standard maneuver rules. It is worth noting in these rules, you can still attempt to do maneuvers without getting a strong hit, only it takes your action. This may still be worth it in some cases, as you'd only need to succeed one roll, instead of succeeding an attack with an even number, then succeeding a second roll.
*While attacks of opportunity may seem counterproductive if my goal is to increase the amount of movement in combat, without it my system falls apart somewhat. Since in this system you can force movement on your opponent there needs to be an incentive not to immediately undo that movement. For example if you push back your foe to the edge of a cliff, without a reason to stay in that spot, your foe can simply move away from the cliffside. they may be more likely to stay there and fight if the threat of an attack of opportunity is eminent. Attacks of Opportunity do not activate Strong Hits.

Tuesday, April 25, 2023

In the realm of me, april 2023.

Thursday, February 16, 2023

Blackjackal dice game, for your rpg gambling pleasure.

Today's Blogpost is about a simple dice game to throw into your games when the players are feeling lucky. It's quite simple, and is a good mix of luck and skill, in my opinion. It plays very similar to blackjack, only with d12s instead of cards. Here are the rules:

One person is the dealer, this is most likely the house, but a player with a particularly large sum could take this role as well.
First, the Players put in their bets. You can decide if the table will have a minimum or not.
The Dealer then rolls 4d12, dropping as many dice as it takes to get below 25. They then reveal one of the dice.
The Players now decide if they want to add more to their bet or fold. Again decide if there should be a minimum.
The players now choose how many d12s they would like to roll. There is no maximum, however if they roll above 24 they lose.
The goal of the game is to get above the dealer without going over 24.
Finally the Dealer reveals their whole dice pool. If the Dealer wins they take the bet, if the Player wins the dealer matches what they put in.
If anyone gets a perfect 24 that's called a BlackJackal, and they get the entire table's bets, on top of what the dealer owes them. If multiple people get a BlackJackal, then they split the pot evenly.

And that's it! This is a pretty popular game at the Travelling Alchemist, you can find many adventurers losing their hard-earned loot at our beer stained tables. Some shifty fellows even like to bet secrets and rumors in lieu of money.

If you want to have the players roll for a skill check on top of playing the game (for example Savage Worlds has a gambling skill), have them make the check. If they succeed let them add or subtract an extra die after their initial roll, to signify their character correctly calculating the odds. If a player wants to cheat let them make the skill check, then change the face of a die if they succeed.

However you play I hope you have fun, and Happy Gaming!

Friday, February 10, 2023

Using pc theme songs to showcase your heroes.

So today's blog post is about giving the PCs of your rpg campaign theme songs. Obviously, this isn't for every game but if your running a game where the PCs are supposed to be badasses, reminiscent of action hero movies and the like this may be the perfect fit. Especially if music is important at your table.

The setup would be quite simple. During your session zero have each of the players choose a song they think represents their character well. This might work better for a modern or cyberpunk setting so that the players can choose recognizable songs that wouldn't clash with your playlist. Add these songs to your playlist. Now you can decide how long you want your playlist to be. If you only play music during combat then you'll probably want it shorter, but if you play music the whole session you'll want it longer, maybe around 6 hours. When a PC's song comes up give that PC some sort of bonus.

A few ideas may be:

Give them a static bonus to their next turn (IE a +3 bonus to all rolls in D&D 5e)
Let them auto-succeed on their next action
My favorite, let them describe how the party gets some sort of edge in the scene they're in because of the PC's badassery (IE letting the PC describe how they use their stealthy skills to sneak past a security system, how they smooth talk with a crime boss, etc, etc)

Finally, my favorite use of this mechanic is what I call " The Blaze of Glory ". At any time the player can either ask the GM to play their song or pull out their phone and begin playing their theme. When a player does this they take control of the scene and describe how they overcome the obstacles, defeat the villain, whatever. But at the end of the scene or song, that PC dies in a blaze or glory. This can create super impactful moments where a PC makes the ultimate sacrifice, all the while the song that highlighted so many of their achievements plays in the background.

Let me know if you use this in your own games or one-shots, and how you would modify it for your own use. Until next time, this is Drew of the Travelling Alchemist.

Thursday, January 26, 2023

Custom frostgrave scenario: gorepin's manor.

Here's some photos of some of the warbands I painted and the ruins of Gorepins manor!

Wednesday, January 25, 2023

Randomly generating backgrounds and the "your storied past" table.

Recently I've just had a session 0 for a campaign I am running in Savage Worlds where I decided to take inspiration from Cyberpunk RED, which I had ran the previous summer. In RED you go through what is called lifepath generation, where you roll for or choose various aspects of your character background, until you have a fleshed out Edgerunner of your own. My favorite part of the lifepath system is rolling for friends, enemies, and tragic love stories. With just these 3 things I was able to run my summer Cyberpunk campaign with little to no prep, and it was a blast. It also forced the players to work within limits, which as many of us know, limitation breeds creativity.

So while prepping this campaign I knew I wanted to do something similar. But, as I was now running a dark fantasy setting, not all the options would translate. So I took this as an opportunity to innovate on Cyberpunks lifepath system.

After a few hours I created the Your Storied Past table. with only 2d20 you can easily generate an invocative story from the past that frames your characters motivation. I have included this table below.

My table used this to great success, I'm happy to say. And all the player agreed afterward, most had never used random character generation, that it had led to very interesting characters which were slightly out of their comfort zone (in a good way of course).

In addition to this table we also used a slightly modified version of cyberpunks friends, enemies, and tragic love stories, as well as the relationships page from " This is Totally Not another D&D Fiasco " by Dyson Logos. Between the three resources, we are starting off our game with a lot of player cohesion and useful background details.

This table can be found here , on my google drive. It is Licensed under Creative a Creative Commons Attribution 4.0 BY NC SA International License

Quickie today! I've been running Starfinder recently, and with the final session coming up I needed to prepare the ship the party would...

10 Best Anime Series Every Fan of Frieren: Beyond Journey's End Needs to Watch

There are plenty of anime that are great for fans of Frieren: Beyond Journey's End .
Some anime are great for offering similar takes on adventuring through fantasy worlds as Frieren does.
Others are great for the overlap they have with Frieren 's writing style and overall themes.

Frieren: Beyond Journey’s End is easily one of the biggest anime of the past few years. Not only does it have gorgeous art, animation, and overall direction, but its straightforward take on the fantasy genre, combined with intelligent and emotionally resonant writing, made it a major hit among fans and critics alike to a degree that very few anime have ever managed to achieve.

The first season of Frieren received unanimous praise from fans and critics alike. It’s currently unknown when Frieren: Beyond Journey’s End will return for a second season, if at all, but fortunately, there are plenty of anime that fans of the series can watch.

As unique a series as it may be, there are plenty of great anime that overlap with Frieren: Beyond Journey’s End in terms of themes, characters, and overall quality ; a few anime, in particular, are especially worth highlighting, and any fan of Frieren: Beyond Journey’s End is sure to get a lot out of them, even if it’s not the same experience.

10 Best Fantasy Anime Every Lord of the Rings Fan Needs to Watch

Wandering witch captures the same pure essence of traveling as frieren, anime series by c2c; based on the light novel by jogi shiraishi.

C2C’s Wandering Witch: The Journey of Elaina stars Elaina the Ashen Witch, a young witch who travels the world in the hopes of living a life of adventure like her idol, the great witch Niké. Elaina takes it upon herself to not interfere in anything she witnesses on her travels, no matter how terrible something may be, but there are occasions where, at the very least, Elaina’s passivity does deeply affect her and force her to question her resolve.

Wandering Witch isn’t that well-known of an anime, but it’s still a great recommendation for fans of Frieren: Beyond Journey’s End . Wandering Witch: The Journey of Elaina is, like Frieren: Beyond Journey’s End , a thoughtful story of a magical being traveling across the world , but Elaina is a far more selfish person than Frieren, so it creates a different sort of traveling story, especially when her selfishness ends up hurting herself and others. Overall, Wandering Witch has the same sort of aesthetic as Frieren , but adds a unique-enough flavor to create a different experience, so it’s plenty worth checking out.

Kinos Journey Highlights The Beauty & Danger Of The World, Just Like Frieren

Anime series by acgt; based on the light novel by keiichi sigsawa.

ACGT’s Kino’s Journey—the Beautiful World— is about Kino, a young girl traveling the world with no one by her side except her talking motorcycle, Hermes. Kino makes it a rule not to stay in one place longer than three days in two nights to keep herself from getting too attached, and with how dangerous some of the places she visits can be, she always makes sure to keep a variety of weapons with her, most notably her .44 single-action revolver the “Cannon” and her .22 automatic pistol the “Woodsman”.

Similar to Wander Witch: The Journey of Elaina , Kino’s Journey—the Beautiful World— is great for anyone who was a fan of the adventuring aspect of Frieren: Beyond Journey’s End . Not only do both stories have characters going on episodic adventures around the world, but the dark and fantastical nature of the places in Kino’s Journey—the Beautiful World— always adds something new to each story , whether it’s purely in aesthetic or in the themes the audience is expected to contemplate. Adventure is always used for thought-provoking storytelling, so that makes it perfect for fans of Frieren: Beyond Journey’s End .

Mushishi Is Another Great Anime About Supernatural Good Samaritans

Anime series by artland; based on the manga by yuki urushibara.

Artland’s Mushishi is an episodic anime set vaguely in 19th-century Japan where people are constantly plagued by ethereal beings called Mushi. As one of the few people who can see Mushi, series protagonist Ginko has taken it upon himself to research Mushi and aid those who suffer because of them whenever he comes across them in his travels.

From start to finish, Mushishi is an anime that does a great job of playing into the same core aesthetic of Frieren: Beyond Journey’s End . The element of traveling through a supernatural setting is one thing, but Mushishi being an episodic story of a supernatural good samaritan has a clear overlap with Frieren: Beyond Journey’s End , although Mushishi is the far more episodic story of the two. Nevertheless, both anime excellently play into the idea of good people just trying to help others, so any fan of one is sure to get a lot out of the other.

To Your Eternity Is Another Great Story About The Struggles Of Immortality

Anime series by drive; based on the manga by yoshitoki oima.

Drive’s To Your Eternity opens with a mysterious being called the Beholder releasing an orb into the world that takes on the form of anything that dies around it. The orb eventually becomes an immortal being named Fushi, and through his travels, he constantly befriends new people he’s always fated to outlive and must slowly come to understand why living that sort of life is so tragic.

Unlike some other anime, To Your Eternity ’s overlap with Frieren: Beyond Journey’s End is through one of the more tragic elements of its story. Both To Your Eternity and Frieren: Beyond Journey’s End revolve around nigh-immortal beings dealing with the reality of outliving the people closest to them , and sure enough, both anime use it to tell tragic and bittersweet stories from start to finish. The emotional beats of Frieren ’s writing have always been one of its biggest draws, and anyone who’s a fan of that is sure to be a fan of To Your Eternity .

Bocchi The Rock! Is Another Gorgeous Anime From Frierens Director

Anime series by cloverworks; based on the manga by aki hamazi.

CloverWorks’ Bocchi the Rock! stars Hitori Gotoh, a girl with crippling social anxiety who learned to play guitar in the hopes of using it to make friends, although her efforts never once managed to bear fruit. One day, however, Hitori is recruited to be the new guitarist in the band Kessoku Band, and as Hitori - now with the nickname Bocchi - commits herself to the band, she’ll find herself slowly but surely gaining the exact life she hoped for when she first started learning the guitar.

Bocchi the Rock! is a completely different story from Frieren: Beyond Journey’s End , but that doesn’t mean fans of the latter shouldn’t watch it. Both anime were directed by anime director Keiichiro Saito, and sure enough, both Bocchi the Rock! and Frieren: Beyond Journey’s End feature some of the best animation and overall direction of any anime that’s come out within the past few years. Keiichiro Saito is one of the best directors to come out of anime in the past few years, and if anyone wants to see what else he’s capable of, there’s no better anime to watch than Bocchi the Rock!

Spice And Wolf Excellently Makes The Mundane Entertaining

Anime series by brain's base & passione; based on the light novel by isuna hasekura, spice and wolf: merchant meets the wise wolf (2024).

Cast Jun Fukuyama, Ami Koshimizu

Release Date April 2, 2024

Genres Drama, Adventure, Anime

Main Genre Anime

Rating TV-14

Spice and Wolf is a low-fantasy anime about a traveling merchant named Kraft Lawrence who, one day, comes across a woman with wolf ears and a tail sleeping in his cart. The woman introduces herself as a harvest goddess named Holo, and after Lawrence helps Holo leave the confines of the village where they met, the two embark on a journey to bring Holo back to her birthplace while doing merchant work whenever and wherever it might come up.

Spice and Wolf is a very different sort of fantasy series from Frieren , but their similarities become readily apparent in their writing. In addition to characters having dry wit and largely unexaggerated dialogue, Spice and Wolf , much like Frieren: Beyond Journey’s End , is much more focused on the minute details of worldbuilding than it is on the action , specifically the inner workings of economics and trading, and the execution always keeps it from being boring. It's a perfect anime for fans of Frieren , and with the Spice and Wolf reboot , now's the perfect time for someone to start watching.

Magis Worldbuilding & Magic Are Perfect For Frieren Fans

Anime series by a-1 pictures; based on the manga by shinobu ohtaka, magi: the labyrinth of magic (2012).

Cast Erica Mendez, Lucien Dodge, Cristina Valenzuela, Erik Scott Kimerer, Darrel Guilbeau, Matthew Mercer, Stephanie Sheh

Release Date October 7, 2012

Genres Animation, Action, Fantasy

Streaming Service(s) Crunchyroll

Franchise(s) Magi: The Labyrinth of Magic

Writers Hiroyuki Yoshino

Directors Naotaka Hayashi, Koji Masunari

Main Genre Fantasy

Creator(s) Shinobu Ohtaka

A-1 Pictures’ Magi: The Labyrinth of Magic depicts an Arabian Nights -style fantasy world where people can challenge mysterious dungeons for untold wealth and power that can change the world. Among the people who have a go at this are the young pair of Aladdin and Alibaba, and while the two of them originally just wanted to go on an adventure, they soon find themselves wrapped up in one major conspiracy after another that are all poised to upend everything they know about their world.

Magi: The Labyrinth of Magic ’s flavor of fantasy is very different from Frieren: Beyond Journey’s End , but fans of Frieren can still get a lot out of it. Much like Frieren: Beyond Journey’s End , Magi: The Labyrinth of Magic has incredibly intricate worldbuilding through its political elements and its highly-developed magic system , two things that are essential parts of Frieren ’s writing. It’s more lighthearted than some of its contemporaries, but with that sort of writing, it’s a perfect recommendation for fans of Frieren: Beyond Journey’s End .

Violet Evergarden Is A Beautiful Exploration Into Humanity

Anime series by kyoto animation; based on the light novel by kana akatsuki, violet evergarden.

Cast Ben Pronsky, Christine Marie Cabanos, Tony Azzolino, Kyle McCarley, Reba Buhr, Erika Harlacher

Release Date January 11, 2018

Genres Drama

Streaming Service(s) Netflix

Franchise(s) Violet Evergarden

Writers Taaki Suzuki, Tatsuhiko Urahata, Reiko Yoshida

Directors Taichi Ishidate, Haruka Fujita

Main Genre Animation

Creator(s) Kana Akatsuki

The titular hero of Kyoto Animation’s Violet Evergarden is a former orphan turned soldier who spent her entire life fighting in a war that’s only now come to an end. Now needing a new purpose in life, Violet takes up a job as a special type of ghostwriter called an Auto Memory Doll in the hopes that writing for others will help better understand people, and she especially hopes it will help her understand why her commanding officer told her he loved her before he died.

Kyoto Animation is famous for its emotionally driven anime, and Violet Evergarden is easily one of its best. From start to finish, Violet Evergarden does an excellent job of depicting its hero’s struggles with learning what it means to be human in an emotionally poignant fashion , something that, of course, is at the core of Frieren: Beyond Journey’s End ’s overarching narrative. Add in the consistently gorgeous visuals and overall direction, and Violet Evergarden hits nearly all the same aesthetics that made Frieren: Beyond Journey’s End such a hit.

Delicious In Dungeon Is The Perfect Fantasy To Complement Frieren

Anime series by studio trigger; based on the manga by ryoko kui, delicious in dungeon.

Cast Asuna Tomari, Hiroshi Naka, Kentarou Kumagai, Sayaka Senbongi

Release Date January 1, 2024

Genres Cooking, Comedy, Fantasy

Franchise(s) Delicious in Dungeon

Writers Kimiko Ueno, Ryoko Kui

Directors Yoshihiro Miyajima

In Studio Trigger’s hit fantasy anime Delicious in Dungeon , the adventure party of series protagonist Laios is wiped out by a dragon, with Laios’ sister, Falin, even being eaten alive. Laios and what remains of his party need to hurry back through the dungeon to revive Falin, but they lack the funds for the journey and have no time to gather them up. To deal with the situation, Laios convinces everyone, much to their disgust, to eat the monsters they encounter in the dungeon, something Laios is all but stated to have just been looking for an excuse to do.

Delicious in Dungeon is great for fans of Frieren thanks to largely being its opposite. While they’re both largely straightforward fantasy anime, Delicious in Dungeon , while not wholly unserious, has a far more comedic approach to fantasy than Frieren: Beyond Journey’s End , so the two can be seen as two sides of the same coin and of equal value to anime fans looking for something different from isekai and power fantasy anime. Add in its own uniquely great writing and animation, and Delicious in Dungeon makes for as great a watch as Frieren for a lot of the same reasons.

Fullmetal Alchemist & Frieren Are Both Excellent Gateways Into Anime

Anime series by studio bones; based on the manga by hiromu arakawa, fullmetal alchemist.

Created by Hiromu Arakawa

TV Show(s) Fullmetal Alchemist, Fullmetal Alchemist: Brotherhood

Character(s) Greed (Fullmetal Alchemist), Envy (Fullmetal Alchemist), Lust (Fullmetal Alchemist), King Bradley, May Chang, Lan Fan, Ling Yao, Scar (Fullmetal Alchemist), Riza Hawkeye, Maes Hughes, Winry Rockbell, Roy Mustang, Alphonse Elric, Edward Elric

Studio Bones’ Fullmetal Alchemist is set in a world where alchemy is very much real, and in the nation of Amestris, alchemists can join the military in exchange for near-limitless authority. One of these state alchemists is Edward Elric, the titular Fullmetal Alchemist, and after an accident with alchemy costs Edward his limbs and forces the soul of his brother Alphonse to be bound to a suit of armor, Edward starts looking for the mythical Philosopher’s Stone in the hopes of restoring their bodies, completely unaware of the forces his journey will bring him into contact with.

10 Best Anime So Good They'll Turn Even the Most Skeptical Viewers Into Fans

Notably, Fullmetal Alchemist was replaced by Frieren: Beyond Journey’s End in many anime rankings' top spot, despite being completely different in both genre and story. Thanks to its stellar art and animation and a story that’s both entertaining and not too overly complex, Fullmetal Alchemist , like Frieren: Beyond Journey’s End , is one of the best anime for getting people invested in anime , something that hasn’t changed in the slightest after over a decade. There’s a definite overlap between the two in that regard, and that’s why Fullmetal Alchemist is probably the best anime for fans of Frieren: Beyond Journey’s End .

10 Best Anime Series Every Fan of Frieren: Beyond Journey's End Needs to Watch

IMAGES

Jessica Alba & the Time Travelling Alchemist
Inside the Medieval and Early Modern Alchemist’s Workshop
A Beginner’s Guide To Time Travel
The Travelling Alchemist! Made using: Blender, Zbrush, and Substance
The Slow Life of a Travelling Alchemist
Medieval Alchemist Science Medicine Alchemy Scientist Early Chemistry

VIDEO

MSD -Untitled- _A_ (WAR 007)
In The Studio: The Alchemist & Larry June Working On "60 Days"
The Science Behind Time Travel
Fullmetal Alchemist
Alchemist coffee shop in ajmer #coffeelover #ajmer #restuarant #viralvideos #viralshorts
The Alchemist

COMMENTS

Count of St. Germain
The character of Jack Elderflower in the novel Gather the Fortunes, by Bryan Camp. The Comte is a significant character in the Victorian time-travel novella, A Peculiar Count in Time, by M .K. Beutymhill. The Comte is the main protagonist in an ongoing series of historical romance/horror novels by Chelsea Quinn Yarbro.
Composer, Alchemist, Poet and ... Time Traveler Immortal?
Composer, Alchemist, Poet and ... Time Traveler Immortal? i. Sep 13, 2017 · by James Bennett II. Imagine you're at a dinner party and out of nowhere comes a complete stranger who seems to know everything about everything, speaks five languages and claims to be immortal. The magnetizing gent you've encountered in this completely ...
Time Travel
Time Travel. First published Thu Nov 14, 2013; substantive revision Fri Mar 22, 2024. There is an extensive literature on time travel in both philosophy and physics. Part of the great interest of the topic stems from the fact that reasons have been given both for thinking that time travel is physically possible—and for thinking that it is ...
This Monkey Came From the FUTURE!?! (Time Traveling Alchemist ...
This Monkey Came From the FUTURE!?! (Time Traveling Alchemist in BTD 6)Mod made by DatJaneDoe!#BloonsTD6 #BTD6 #ModToday we're playing more hacked Bloons TD ...
Paradox-Free Time Travel Is Theoretically Possible, Researchers Say
Time Travel Theoretically Possible Without Leading To Paradoxes, Researchers Say In a peer-reviewed journal article, University of Queensland physicists say time is essentially self-healing ...
Thomas F. Staley: Alchemist and Time Traveler
Alchemist and Time Traveler. As the legend goes, an ambitious young professor with a newly minted PhD from Pitt came home to Tulsa with the aim of making what was then the oil capital of the world into an intellectual powerhouse. So, in 1963, he took to his garage and, with the help of a few students, began laying out a modestly sized magazine ...
The Alchemist (novel)
The Alchemist (Portuguese: O Alquimista) is a novel by Brazilian author Paulo Coelho which was first published in 1988. Originally written in Portuguese, it became a widely translated international bestseller. The story follows the shepherd boy Santiago in his journey across North Africa to the pyramids of Egypt after he dreams of finding a treasure there.
Santiago Character Analysis in The Alchemist
Paulo Coelho. Santiago. Santiago, a shepherd boy from a small Andalusian town, is the protagonist of The Alchemist. He is determined, headstrong, and curious to learn all he can about the world. As a result, he resisted his parent's desires that he become a priest and chose instead to work as a shepherd so that he would have the opportunity ...
Time travel
The first page of The Time Machine published by Heinemann. Time travel is the hypothetical activity of traveling into the past or future.Time travel is a widely recognized concept in philosophy and fiction, particularly science fiction. In fiction, time travel is typically achieved through the use of a hypothetical device known as a time machine.The idea of a time machine was popularized by H ...
The Alchemist: Full Book Summary
Paulo Coelho. The Alchemist Full Book Summary. A recurring dream troubles Santiago, a young and adventurous Andalusian shepherd. He has the dream every time he sleeps under a sycamore tree that grows out of the ruins of a church. During the dream, a child tells him to seek treasure at the foot of the Egyptian pyramids.
Can we time travel? A theoretical physicist provides some answers
The simplest answer is that time travel cannot be possible because if it was, we would already be doing it. One can argue that it is forbidden by the laws of physics, like the second law of ...
Alchemy
Alchemy is an ancient practice aimed at recreating precious substances using recipes and transformative materials such as the philosopher's stone. Alchemists believed that materials like gold, silver, gems, and purple dye could be recreated if the right combination of ingredients and transformative methods were found.Other avenues of exploration in later centuries were aimed at increasing the ...
The Route of Santiago in The Alchemist
"People are capable, at any time in their lives of doing what they dream of." ~ The Alchemist. The Route Of Santiago Alchemist. Santiago's journey is not only a spiritual discovery of his potential but also a travel saga. He covers three countries in his wake. He crosses Spain, Morocco, and Egypt to get to his destination.
Setting of The Alchemist by Paulo Coelho
Avoiding the explicit mention of a time period in "The Alchemist makes its ... These settings metaphorically illustrate the spiritual growth that comes from traveling to new places. The time ...
The Best Fictional Characters Who Time Travel
Time travel is an extremely interesting subject in fiction because it deals with a myriad of themes and issues. Traveling in time allows fictional characters to deal with history, the future, or both with modern day characters. Characters who time travel range from average Joes who stumbled into time travel, to hundred year old aliens who love ...
Physics: The time lord and fellow travellers
As television's time-bending Doctor Who turns 50, Andrew Jaffe explores time travel in fiction and science. In 1963, an extraterrestrial burst from his time machine and onto British television ...
Time Travel Manga
Complete list of time travel manga. Time travel is the concept of moving between different points in time, usually with an invention called a time machine. The science is loosely based in theoretical physics, with quantum mechanics and wormholes as common themes. These titles either focus on the concept of time travel or include time travel, often involving a Person in a Strange World.
An Alchemist's Travels, according to Himself
The figure of Leonard embodies an alchemical persona emerging at the time, as he typifies the generic travel-narrator's personality. Leonard casts himself as an eyewitness to wonders of a wider world; he is a loyal companion whose trustworthiness was proved on the road; he is a world-wearied, retired adventurer who has gathered up knowledge ...
The Interconnectedness of All Things Theme in The Alchemist
The Interconnectedness of All Things Quotes in The Alchemist. Below you will find the important quotes in The Alchemist related to the theme of The Interconnectedness of All Things. Part One Quotes. "You came so that you could learn about your dreams," said the old woman. "And dreams are the language of God.
Is Time Travel Possible?
In Summary: Yes, time travel is indeed a real thing. But it's not quite what you've probably seen in the movies. Under certain conditions, it is possible to experience time passing at a different rate than 1 second per second. And there are important reasons why we need to understand this real-world form of time travel.
Alchemy Timeline
Definition. Alchemy is an ancient practice aimed at recreating precious substances using recipes and transformative materials such as the philosopher's stone. Alchemists believed that materials like gold, silver, gems, and purple dye could be recreated if the right combination of ingredients and transformative methods were found. Other avenues ...
The Travelling Alchemist
Throughout all time and all realities, there is one constant. Tucked away on some back street, inside the walls of an unassuming wooden building, there is a tavern that exists everywhere. It is called the Travelling Alchemist, and throughout time it has had many owners.
10 Best Anime Series Every Fan of Frieren: Beyond Journey's End ...
ACGT's Kino's Journey—the Beautiful World— is about Kino, a young girl traveling the world with no one by her side except her talking motorcycle, Hermes. Kino makes it a rule not to stay ...