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Is time travel possible? Why one scientist says we 'cannot ignore the possibility.'

A common theme in science-fiction media , time travel is captivating. It’s defined by the late philosopher David Lewis in his essay “The Paradoxes of Time Travel” as “[involving] a discrepancy between time and space time. Any traveler departs and then arrives at his destination; the time elapsed from departure to arrival … is the duration of the journey.”

Time travel is usually understood by most as going back to a bygone era or jumping forward to a point far in the future . But how much of the idea is based in reality? Is it possible to travel through time? 

Is time travel possible?

According to NASA, time travel is possible , just not in the way you might expect. Albert Einstein’s theory of relativity says time and motion are relative to each other, and nothing can go faster than the speed of light , which is 186,000 miles per second. Time travel happens through what’s called “time dilation.”

Time dilation , according to Live Science, is how one’s perception of time is different to another's, depending on their motion or where they are. Hence, time being relative. 

Learn more: Best travel insurance

Dr. Ana Alonso-Serrano, a postdoctoral researcher at the Max Planck Institute for Gravitational Physics in Germany, explained the possibility of time travel and how researchers test theories. 

Space and time are not absolute values, Alonso-Serrano said. And what makes this all more complex is that you are able to carve space-time .

“In the moment that you carve the space-time, you can play with that curvature to make the time come in a circle and make a time machine,” Alonso-Serrano told USA TODAY. 

She explained how, theoretically, time travel is possible. The mathematics behind creating curvature of space-time are solid, but trying to re-create the strict physical conditions needed to prove these theories can be challenging. 

“The tricky point of that is if you can find a physical, realistic, way to do it,” she said. 

Alonso-Serrano said wormholes and warp drives are tools that are used to create this curvature. The matter needed to achieve curving space-time via a wormhole is exotic matter , which hasn’t been done successfully. Researchers don’t even know if this type of matter exists, she said.

“It's something that we work on because it's theoretically possible, and because it's a very nice way to test our theory, to look for possible paradoxes,” Alonso-Serrano added.

“I could not say that nothing is possible, but I cannot ignore the possibility,” she said. 

She also mentioned the anecdote of  Stephen Hawking’s Champagne party for time travelers . Hawking had a GPS-specific location for the party. He didn’t send out invites until the party had already happened, so only people who could travel to the past would be able to attend. No one showed up, and Hawking referred to this event as "experimental evidence" that time travel wasn't possible.

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A beginner's guide to time travel

Learn exactly how Einstein's theory of relativity works, and discover how there's nothing in science that says time travel is impossible.

Everyone can travel in time . You do it whether you want to or not, at a steady rate of one second per second. You may think there's no similarity to traveling in one of the three spatial dimensions at, say, one foot per second. But according to Einstein 's theory of relativity , we live in a four-dimensional continuum — space-time — in which space and time are interchangeable.

Einstein found that the faster you move through space, the slower you move through time — you age more slowly, in other words. One of the key ideas in relativity is that nothing can travel faster than the speed of light — about 186,000 miles per second (300,000 kilometers per second), or one light-year per year). But you can get very close to it. If a spaceship were to fly at 99% of the speed of light, you'd see it travel a light-year of distance in just over a year of time. 

That's obvious enough, but now comes the weird part. For astronauts onboard that spaceship, the journey would take a mere seven weeks. It's a consequence of relativity called time dilation , and in effect, it means the astronauts have jumped about 10 months into the future. 

Traveling at high speed isn't the only way to produce time dilation. Einstein showed that gravitational fields produce a similar effect — even the relatively weak field here on the surface of Earth . We don't notice it, because we spend all our lives here, but more than 12,400 miles (20,000 kilometers) higher up gravity is measurably weaker— and time passes more quickly, by about 45 microseconds per day. That's more significant than you might think, because it's the altitude at which GPS satellites orbit Earth, and their clocks need to be precisely synchronized with ground-based ones for the system to work properly. 

The satellites have to compensate for time dilation effects due both to their higher altitude and their faster speed. So whenever you use the GPS feature on your smartphone or your car's satnav, there's a tiny element of time travel involved. You and the satellites are traveling into the future at very slightly different rates.

But for more dramatic effects, we need to look at much stronger gravitational fields, such as those around black holes , which can distort space-time so much that it folds back on itself. The result is a so-called wormhole, a concept that's familiar from sci-fi movies, but actually originates in Einstein's theory of relativity. In effect, a wormhole is a shortcut from one point in space-time to another. You enter one black hole, and emerge from another one somewhere else. Unfortunately, it's not as practical a means of transport as Hollywood makes it look. That's because the black hole's gravity would tear you to pieces as you approached it, but it really is possible in theory. And because we're talking about space-time, not just space, the wormhole's exit could be at an earlier time than its entrance; that means you would end up in the past rather than the future.

Trajectories in space-time that loop back into the past are given the technical name "closed timelike curves." If you search through serious academic journals, you'll find plenty of references to them — far more than you'll find to "time travel." But in effect, that's exactly what closed timelike curves are all about — time travel

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There's another way to produce a closed timelike curve that doesn't involve anything quite so exotic as a black hole or wormhole: You just need a simple rotating cylinder made of super-dense material. This so-called Tipler cylinder is the closest that real-world physics can get to an actual, genuine time machine. But it will likely never be built in the real world, so like a wormhole, it's more of an academic curiosity than a viable engineering design.

Yet as far-fetched as these things are in practical terms, there's no fundamental scientific reason — that we currently know of — that says they are impossible. That's a thought-provoking situation, because as the physicist Michio Kaku is fond of saying, "Everything not forbidden is compulsory" (borrowed from T.H. White's novel, "The Once And Future King"). He doesn't mean time travel has to happen everywhere all the time, but Kaku is suggesting that the universe is so vast it ought to happen somewhere at least occasionally. Maybe some super-advanced civilization in another galaxy knows how to build a working time machine, or perhaps closed timelike curves can even occur naturally under certain rare conditions.

This raises problems of a different kind — not in science or engineering, but in basic logic. If time travel is allowed by the laws of physics, then it's possible to envision a whole range of paradoxical scenarios . Some of these appear so illogical that it's difficult to imagine that they could ever occur. But if they can't, what's stopping them? 

Thoughts like these prompted Stephen Hawking , who was always skeptical about the idea of time travel into the past, to come up with his "chronology protection conjecture" — the notion that some as-yet-unknown law of physics prevents closed timelike curves from happening. But that conjecture is only an educated guess, and until it is supported by hard evidence, we can come to only one conclusion: Time travel is possible.

A party for time travelers 

Hawking was skeptical about the feasibility of time travel into the past, not because he had disproved it, but because he was bothered by the logical paradoxes it created. In his chronology protection conjecture, he surmised that physicists would eventually discover a flaw in the theory of closed timelike curves that made them impossible. 

In 2009, he came up with an amusing way to test this conjecture. Hawking held a champagne party (shown in his Discovery Channel program), but he only advertised it after it had happened. His reasoning was that, if time machines eventually become practical, someone in the future might read about the party and travel back to attend it. But no one did — Hawking sat through the whole evening on his own. This doesn't prove time travel is impossible, but it does suggest that it never becomes a commonplace occurrence here on Earth.

The arrow of time 

One of the distinctive things about time is that it has a direction — from past to future. A cup of hot coffee left at room temperature always cools down; it never heats up. Your cellphone loses battery charge when you use it; it never gains charge. These are examples of entropy , essentially a measure of the amount of "useless" as opposed to "useful" energy. The entropy of a closed system always increases, and it's the key factor determining the arrow of time.

It turns out that entropy is the only thing that makes a distinction between past and future. In other branches of physics, like relativity or quantum theory, time doesn't have a preferred direction. No one knows where time's arrow comes from. It may be that it only applies to large, complex systems, in which case subatomic particles may not experience the arrow of time.

Time travel paradox 

If it's possible to travel back into the past — even theoretically — it raises a number of brain-twisting paradoxes — such as the grandfather paradox — that even scientists and philosophers find extremely perplexing.

Killing Hitler

A time traveler might decide to go back and kill him in his infancy. If they succeeded, future history books wouldn't even mention Hitler — so what motivation would the time traveler have for going back in time and killing him?

Killing your grandfather

Instead of killing a young Hitler, you might, by accident, kill one of your own ancestors when they were very young. But then you would never be born, so you couldn't travel back in time to kill them, so you would be born after all, and so on … 

A closed loop

Suppose the plans for a time machine suddenly appear from thin air on your desk. You spend a few days building it, then use it to send the plans back to your earlier self. But where did those plans originate? Nowhere — they are just looping round and round in time.

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Andrew May holds a Ph.D. in astrophysics from Manchester University, U.K. For 30 years, he worked in the academic, government and private sectors, before becoming a science writer where he has written for Fortean Times, How It Works, All About Space, BBC Science Focus, among others. He has also written a selection of books including Cosmic Impact and Astrobiology: The Search for Life Elsewhere in the Universe, published by Icon Books.

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Is Time Travel Possible?

Truthseeker007

• Feb 13, 2020

And obvious things like when you look at the stars at night you are looking thousands of years in the past. You can go back in time in your mind to something that happened a few years ago. Good psychics can tap into the energies of the future.  

• Feb 18, 2020

May I ask how off were the two clocks Secondly, shouldn't we be able to time travel to the past because it is made from certain particles from elements (periodic table) then we would be able to recreate that in the past because of the theory of multiverses you can go back in time but that's still your universe it just makes it so that you are in that time but your time at the same time (IDK if you understand but yeah)  

• Dec 27, 2020

SaraRayne said: What good sci-fi movie doesn’t involve time travel of some sort? It’s an intriguing concept, and one that fascinates humans, enough so that we’ve even come up with “time travel rules”, just in case. But is this all just fantasy? Or could we actually figure out the science behind time travel one day? Here’s what the experts think: 1. Time dilation is technically time travel. Einstein gave us general relativity, and general relativity has given us the first potential time travel option. Time dilation is a consequence of general relativity and was first demonstrated using an atomic clock experiment. Two clocks were synchronized, and while one stayed on the ground, the other was taken up in an airplane. When they were reunited, the clock that took a ride was slower, and by the exact amount Einstein’s equations predicted. What this essentially demonstrated was that time can be experienced differently depending on frame of reference. That in and of itself is a type of time travel. 2. If wormholes exist… The most popular time travel theory involves wormholes. At this point they’re still in the theoretical realm, but many scientists believe that they’re entirely possible. What wormholes are thought to be are structures that connect two points in space that are extremely far apart. They’re essentially shortcuts that allow you to travel from one location to another instantaneously, whereas to travel the “long way” could take thousands of years. There are a lot of issues when it comes to wormholes, from their creation to how exactly they could be used for transportation. For now, they’re just a concept, but an intriguing one nonetheless. 3. Even if we can, the past is off-limits. Let’s say we do create a traversable wormhole or use time dilation travel in time. What would we be able to do? Time travel paradoxes challenge our understanding of the laws of physics, and one “rule” that has emerged is the idea that if you invented a method of time travel, you wouldn’t be able to travel into the past, because you would be returning to a time when you didn’t have that time travel method and thus the whole thing becomes moot. But that still leaves the future - and there’s a lot of that to explore. Click to expand...

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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!

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).

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.

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:

Can we time travel? A theoretical physicist provides some answers

Emeritus professor, Physics, Carleton University

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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.

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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Time travel without paradoxes is possible with many parallel timelines

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Would-be time travellers have long wrestled with the grandfather paradox: if you change things in the past and prevent yourself ever existing, how did you time travel in the first place? In other words, if Alice goes back in time and kills her grandfather Bob, she won’t have been born and can’t carry out her murderous plot.

One way to avoid such paradoxes is the idea of branching universes, in which the universe we are in splits with each instance…

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Do we live in a rotating universe? If we did, we could travel back in time

Living in a rotating universe would be strange indeed.

We know that planets rotate, but what about the universe as a whole? No, the universe doesn't appear to rotate; if it did, time travel into the past might be possible.

Although people throughout antiquity had argued that the heavens rotate around the world, in 1949, mathematician Kurt Gödel was the first to provide a modern formulation of a rotating universe. He used the language of Albert Einstein 's theory of general relativity to do so, as a way of honoring his friend and neighbor at Princeton, Einstein himself.

But this process of academic "honoring" went in a different direction than you might suspect, because Gödel used the example of a rotating universe to show that general relativity was incomplete.

Related : Was Einstein wrong? The case against space-time theory

Gödel's model of a rotating universe was rather artificial. Besides the rotation, his universe contained only one ingredient: a negative cosmological constant that resisted the centrifugal force of that rotation to keep the universe static.

But the artificial nature of that universe didn't bother Gödel. Instead, his main point was that general relativity allowed for the possibility of a rotating universe at all. And Gödel used his rotating universe to show that general relativity allowed for time travel into the past, which should be forbidden. 

Taking the universe out for a spin

Living in a rotating universe would be strange indeed. For one, all observers would consider themselves the center of rotation. This means that if you parked yourself somewhere and ensured that you were absolutely still, you would see the universe wheeling around you. But if you picked up and moved anywhere else, even to a distant galaxy , you would always still see the universe rotating around your new position.

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This is incredibly hard to visualize, but it's not much different from the idea that in an expanding universe , all observers see themselves as the center of expansion.

The farther you go from any one observer, the greater the rate of rotation. And this isn't merely a rotation of stuff but a rotation of space-time itself. This means that light, which is always forced to follow the curvature of space-time, makes for some strange journeys. A beam of light sent out from an observer will curve away as it gets swept up in the rotation of space-time. At some distant point, the rotation will be too much, and the light will turn around and return to the observer.

This means there's a limit to how far you can see in a rotating universe, and beyond that, all you'll observe is duplicate images of your own past self.

This strange behavior doesn't apply only to light. If you were to get in a rocket and blast off through a rotating universe, you, too, would get caught up in the rotation. And because of that rotation, your movement would double back on itself. When you returned to your starting point, however, you would find yourself arriving before you had left.

In a manner of speaking, a rotating universe would be capable of rotating your future into your own past, allowing you to travel back in time.

Sitting still

This was Gödel's major objection to general relativity. That theory, being our ultimate understanding of space and time , should not allow for backward time travel, because time travel into the past violates our notions of causality and introduces all sorts of nasty time-travel paradoxes. The fact that relativity did not automatically make time travel impossible signaled to Gödel that Einstein's theory was incomplete.

Thankfully, we see no signs that we live in a rotating universe. If the cosmos were rotating, then light coming from opposite directions of the sky would be redshifted in one direction and have an equivalent amount of blueshifting in the other. Astronomers have applied this test to surveys of distant galaxies and even to the cosmic microwave background , which is the light left over from when the cosmos was only 380,000 years old. The conclusion of these tests is that if the universe is rotating, it's doing so at a rate of less than 10^-17 degrees per century. 

— Is time travel possible?

— Why time-traveling tachyons probably don't exist

— What is the grandfather paradox?  

But Gödel's objection still stands. Since 1949, physicists have concocted other ways for general relativity to allow for backward time travel, wormholes , faster-than-light-speed "warp drive" (known as Alcubierre drive), and special paths around infinitely long cylinders. But all those contrivances rely on some sort of exotic physics that breaks our understanding of how the universe works, like matter with negative mass.

But Gödel's rotating universe is simply a matter of observational test, not a fundamental break with known physics. We could have found ourselves in a rotating universe just as easily as we find ourselves in an expanding one. There's nothing in our knowledge of physics that prevents this kind of universe from existing, so there's nothing in our knowledge of physics that prevents backward time travel.

Perhaps Gödel is right, and we have more to learn about the universe.

Learn more by listening to the "Ask A Spaceman" podcast, available on  iTunes  and askaspaceman.com . Ask your own question on Twitter using #AskASpaceman or by following Paul @PaulMattSutter and facebook.com/PaulMattSutter .

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Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute in New York City. Paul received his PhD in Physics from the University of Illinois at Urbana-Champaign in 2011, and spent three years at the Paris Institute of Astrophysics, followed by a research fellowship in Trieste, Italy, His research focuses on many diverse topics, from the emptiest regions of the universe to the earliest moments of the Big Bang to the hunt for the first stars. As an "Agent to the Stars," Paul has passionately engaged the public in science outreach for several years. He is the host of the popular "Ask a Spaceman!" podcast, author of "Your Place in the Universe" and "How to Die in Space" and he frequently appears on TV — including on The Weather Channel, for which he serves as Official Space Specialist.

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Admin said: A rotating universe would be capable of rotating your future into your own past, allowing you to travel back in time. Do we live in a rotating universe? If we did, we could travel back in time : Read more

• mokeshame I think the universe is rotating but some early assumptions have been made in this article. Like the one that we should red and blueshift every lightbeam. Instead red and blueshift are direct evidence that the universe is rotating and because of that appears to be moving away from us. And it goes faster because the universe on a grand scale will ever rotate faster. This is the endgoal of al conservation of energy. Conserve it in rotations as a way of catapulting the universe to all time high rotation speeds. So in the end the speed isnt conservated any more and goes into a strait line. The universe does this to work in on itself. We see actually one particle that can manage itself. Builds his own structure and forms, with no limits. Just like Lego. Spacetime is the exactly the same as the forming of rotations, so it can not be distorted by it i think. A while ago i saw a matmathhecian that exactly formulated it the way i see it, her name was M. Duchin. I think to understand the base and interactions of the universe we must see it as an geniometrical system. Reply
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How would time travel affect life as we know it?

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Key Takeaways

• If unrestricted time travel were possible, it would lead to a complete breakdown of the rational order of things.
• The ability to travel to both the past and future would upend our understanding of time.
• Stephen Hawking's "chronology protection hypothesis" suggests there might be natural laws preventing unrestricted time travel.

Science fiction has thoroughly covered the topic of time travel, starting with H.G. Wells' "The Time Machine" in 1895 and continuing right up to modern movies like " Déjà Vu " starring Denzel Washington. But physicists have also explored the nature of time and the plausibility of time travel for more than century, beginning with Albert Einstein's theories of relativity. Thanks to Einstein, scientists know that time slows as moving objects approach the speed of light. Gravity also slows time. This means that, in one sense, all of us can already consider ourselves time travelers in a limited way because we experience a tiny time warp (a difference of only nanoseconds) when we, for example, take a flight on an airplane. But physicists who study time travel today search for plausible ways to create a time warp large enough to allow noticeable travel into the past or future.

In his book "How to Build a Time Machine," physicist Paul Davies writes, "The theory of relativity implies that a limited form of time travel is certainly possible, while unrestricted time travel -- to any epoch, past or future -- might just be possible, too." This astonishing statement begs an important question: If time travel did indeed become a reality, how would it affect our world as we currently experience it?

First, it's important to realize that building a time machine would likely involve enormous expense, and the sheer complexity of such an apparatus would mean only a limited group of time travelers would have access to it. But even a small group of "astronauts" traveling through time and space could conceivably have a tremendous impact on life as we know it today. The possibilities, in fact, seem almost infinite.

Let's begin by assuming that it's possible to create a complete loop in time travel -- that time travelers could travel back into the past and then return to the future (or vice versa). Although scientists view traveling to the future as a much less problematic proposition than traveling to the past, our daily lives wouldn't change much if we could only send time travelers backward or forward in time, unable to recall them to the present. If we could, in fact, complete this loop of time travel, we can conjure up an incredible array of possible effects.

Possibilities and Paradoxes of Time Travel

Time travel turned total mayhem.

Imagine sending a time traveling astronaut 100 years into the future. The time traveler could witness technological advancements that we can only dream of today, much as people at the turn of the 20th century likely couldn't imagine the items we take for granted in 2010, such as iPods or laptop computers. The time traveler could also gain insight into medical advancements, such as new medicines, treatments and surgical techniques. If the time traveler could bring this knowledge backward in time to the present, the time from which he or she came, society could effectively leap forward in terms of its technical and scientific knowledge.

The futuristic time traveler could also bring back knowledge of what lay ahead for the world. He or she could warn of natural disasters, geopolitical conflicts, epidemics and other events of worldwide importance. This knowledge could potentially change the very way we operate. For example, what if a time traveler journeyed into the future and literally saw the effects that automobiles would eventually have on our planet? What if the time traveler witnessed an environment so polluted and damaged that it's unrecognizable? How might that change our willingness to use alternative forms of transportation?

Imagine that time travel became less restricted and more available to a larger population. Perhaps travel into the future would be exploited for personal gain. A futuristic time traveler could draw on knowledge of the stock market to guide his or her investment decisions, effectively using the granddaddy of all insider information to amass a fortune. Militaries might rely on time travel to gain valuable knowledge about the enemy's positioning and resources in future battles. Terrorists could use time travel to scout out the scenes of future attacks, allowing them to carefully plan with precise knowledge of future conditions.

The potential effects seem equally limitless in terms of the less likely possibility of time travel into the past. History books would no longer be based solely on exhaustive research and interpretation of ancient materials. Time travelers could resolve historical debates and verify how things did or didn't happen in the past. Imagine how different our understanding of the world might be if we could say definitively, for example, whether Moses actually parted the Red Sea or whether Lee Harvey Oswald acted alone in killing John F. Kennedy. A journey into the past could prove or disprove religious beliefs or result in face-to-face encounters with people such as Jesus, Buddha, Napoleon or Cleopatra -- or even the time traveler's former self. Perhaps time travelers could even bring back from the past things that had been lost, such as extinct species or dead and long-forgotten languages.

But here it's very important to raise the issue of self-consistent narratives and paradoxes. The concept of self-consistent narratives tells us that anything a time traveler would alter or affect in the past would have to remain consistent with the future from which he or she journeyed. Changing the past would effectively change the future, creating a causal loop. But such causal loops would only pose inherent problems if changes to the past resulted in a future different from the one the time traveler came from.

But perhaps the question of how time travel would affect life as we know it goes deeper than even a discussion of potential paradoxes and causal loops. Perhaps a discussion of specific effects of consequences on life as we know it makes little sense when faced with something that could change everything about the way in which we perceive our world.

Physicist Paul Davies gives a good example of a consistent causal loop in his book "How to Build a Time Machine." A mathematics professor uses a time machine to travel forward in time, where he discovers a new theorem. He returns back to the time he came from and gives one of his particularly gifted students the idea for that theorem. The student goes on to publish the theorem, and it turns out that it was this very student's work that the professor perused during his journey to the future. The narrative here is consistent.

On the other hand, with the grandfather paradox, a time traveler goes back in time and kills his grandfather. But if the time traveler's grandfather dies before the time traveler is born, how can he or she exist at all? And if the time traveler doesn't exist, how could he or she travel back in time to kill granddad?

As physicist Paul Davies describes it, unrestricted time travel -- meaning time travel that could form a complete loop to both the past and future -- would ultimately lead to total mayhem. In his words, "Time travel opens a view of the world that is a sort of madhouse where the rational order of things would no longer work. Under those circumstances, it's very hard to see how ordinary human life could continue."

In a world where the relationship between past, present and future is turned on its head, we would transcend the things that define our lives today. We would lose our notion of how time works, which could be so fundamentally damaging to our worldview that we would no longer care as much about the things that matter to us today: work, finances, making plans with friends and family, shopping -- you name it. These things just wouldn't be relevant in this crazy new world because we'd have a newfound preoccupation with simply making sense of a world without a set chronology -- we wouldn't know the order in which things occur.

It may be beside the point, then, to talk about resolving historical debates, saving endangered species or gaining technological, financial or military insight because those things might very likely fall by the wayside in the strange world that would follow the advent of unrestricted time travel.

As Davies makes clear, none of this fallout would occur from one-way travel. Hitching a one-way ride to the future or even the past (assuming we stick with self-consistent narratives) wouldn't cause this kind of profound reordering of the world as we currently experience it. But closing that loop of travel could be, in a word, disastrous.

Davies points out that science fiction normally focuses on the novelty aspect of time travel. But according to him, "It's not a novelty or a curiosity, it's something that strikes at the very rational basis of how we live and function. It's really hard to imagine that anything could be the same again." In his view, unrestricted time travel could change life as we know it so dramatically that we wouldn't even recognize it. Because chronology would have no meaning, we couldn't easily tell if something happened before or after, was a cause or an effect, and we would lose the ability to predict rationally the outcomes of our actions. In essence, it would be as though we had all gone insane.

These sobering potential effects of time travel have caused some scientists to wonder whether a principle exists in nature that would actually prevent unrestricted time travel, such as Stephen Hawking's "chronology protection hypothesis." This type of "theory of everything" might provide a scientific explanation as to why we could never unhinge the universe as we know it by making unrestricted time travel a reality. Scientists have yet to discover such a theory, but hearing Davies' take on the frightening effects of time travel makes one hope that they find it soon -- even if it means that we won't ever know for sure who killed JFK.

Frequently Asked Questions

How could time travel impact our understanding of history, what are the ethical implications of time travel, lots more information, related articles.

• What is the fourth dimension?
• What does the fourth dimension have to do with time travel?
• Does gravity distort space-time?
• Are there other universes like ours out there?
• Does time change speed?
• How Special Relativity Works
• How Time Travel Will Work
• Theory of Relativity

More Great Links

• NOVA Online: Time Travel
• Paul Davies' Web site
• ABC Science Online. "The Big Questions: The Riddle of Time." Jan. 17, 2002. (Oct. 7, 2010) http://www.abc.net.au/science/bigquestions/s460740.htm
• Davies, Paul. "How to Build a Time Machine." Penguin Books. 2002.
• Davies, Paul. Personal interview. Oct. 13, 2010.
• PBS Nova. "Sagan on Time Travel." October 1999. (Oct. 7, 2010) http://www.pbs.org/wgbh/nova/time/sagan.html
• Pickover, Clifford. "Time: a traveler's guide." Oxford University Press. 1999.

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Strong geomagnetic storm reaches Earth, continues through weekend

NOAA space weather forecasters have observed at least seven coronal mass ejections (CMEs) from the sun, with impacts expected to arrive on Earth as early as midday Friday, May 10, and persist through Sunday, May 12, 2024. 

NOAA’s Space Weather Prediction Center (SWPC) has issued a Geomagnetic Storm Warning for Friday, May 10. Additional solar eruptions could cause geomagnetic storm conditions to persist through the weekend.

• The First of Several CMEs reached Earth on Friday, May 10 at 12:37 pm EDT.  The CME was very strong and SWPC quickly issued a series of geomagnetic storm warnings. SWPC observed G4 conditions at 1:39 pm EDT (G3 at 1:08 pm EDT).
• This storm is ongoing and SWPC will continue to monitor the situation and provide additional warnings as necessary.

This is an unusual and potentially historic event. Clinton Wallace , Director, NOAA’s Space Weather Prediction Center

CMEs are explosions of plasma and magnetic fields from the sun’s corona. They cause geomagnetic storms when they are directed at Earth. Geomagnetic storms can impact infrastructure in near-Earth orbit and on Earth’s surface , potentially disrupting communications, the electric power grid, navigation, radio and satellite operations. SWPC has notified the operators of these systems so they can take protective action.

Geomagnetic storms can also trigger spectacular displays of aurora on Earth . A severe geomagnetic storm includes the potential for aurora to be seen as far south as Alabama and Northern California.

Related Features //

Watch CBS News

"Extreme" G5 geomagnetic storm reaches Earth, NOAA says, following "unusual" solar event

By Li Cohen

Updated on: May 11, 2024 / 8:32 PM EDT / CBS News

An "extreme" G5 geomagnetic storm reached Earth on Friday, NOAA's Space Weather Prediction Center said , after issuing a watch earlier in the day warning of the potential for a severe impact. 

The watch followed days of solar activity that sent several explosions of plasma and magnetic fields toward Earth. 

G5 is the strongest level of geomagnetic storm , on a scale from G1 to G5. 

"Widespread voltage control problems and protective system problems can occur," NOAA warns. "Some grid systems may experience complete collapse or blackouts. Transformers may experience damage." 

Radio transmissions and satellite navigation may also be disrupted.

The last G5 geomagnetic storm, in October 2003, caused power outages in Sweden and damaged transformers in South Africa.

A geomagnetic storm also means aurora borealis , otherwise known as the northern lights , could be seen as far south as Alabama and in Northern California. 

Earlier, NOAA had issued its first watch for a potential G4-level geomagnetic storm in almost 20 years. "If geomagnetic storms were hurricanes, 'severe' would be category 4," SpaceWeather.com says. 

In a press release on Thursday, NOAA said the most recent series of solar events started on May 8, when a large cluster of sunspots produced "several moderate to strong solar flares." Solar flares are bursts of radiation known to be the solar system's largest explosive events, according to NASA. The area where the flares are occurring is 16 times the diameter of Earth, the NOAA said, and more solar activity is expected. 

That sunspot is so big you may be able to see it with your own eyes  — with your solar eclipse glasses. The spot is known as AR3664 , and it was responsible for most of the geomagnetic activity Friday, the NOAA reported. According to Space.com, it measures about 124,000 miles across and is one of the "largest and most active sunspots seen this solar cycle." 

The NOAA reported that a strong solar flare was observed peaking from AR3664 at 9:23 p.m. Eastern Time Friday. 

"Flares of this magnitude are not frequent," the prediction center said . 

Still have your solar eclipse glasses? There's currently a sunspot so large you will be able to "spot" it while wearing them 15x wider than the earth! pic.twitter.com/XpQJEd4Qk0 — Eric Fisher (@ericfisher) May 9, 2024

There has also been a series of coronal mass ejections (CMEs), which are explosions of plasma  and magnetic fields that come out of the sun's corona, the outermost part of the sun's atmosphere. At least five CMEs appear directed toward Earth and could arrive as early as midday on Friday and persist through Sunday, the agency said. 

"This is an unusual event," NOAA said.

In a call with reporters on Friday, Shawn Dahl, service coordinator at the Space Weather Prediction Center, said that some CMEs "are catching up with other ones." He said officials are expecting a "big shock arrival" when they hit Earth. Dahl said at the time that while officials weren't predicting a G5 storm — the strongest of geomagnetic storms — they couldn't discount a "low-end G5 event."

"We're really buckling down here," Brent Gordon, chief of the space weather services branch, also said on the call.

G4 conditions were detected by Friday afternoon, marking a "major disturbance in Earth's magnetic field," NOAA said, adding that "the public should stay properly informed of storm progression."  

In a forecast discussion at 12:30 p.m. on Friday, NOAA's Space Weather Prediction Center said that solar activity is expected to continue at "high to very high levels" through the weekend, with additional solar flares expected, including X-class flares , the most powerful class of solar flares.

As of Friday afternoon, NOAA said it had observed a moderate solar radiation storm that could expose people in high-flying aircraft to "elevated radiation risk" and cause infrequent issues with satellite operations. 

Radio blackouts have also been detected with an R3 designation, meaning that the blackouts were "strong" on a scale from R1 (minor) to R5 (extreme). At this level, wide blackouts of HF radio communication is expected, as well as loss of radio contact, for about an hour on the sunlit side of Earth, as low-frequency navigation signals decline for roughly an hour. 

"Geomagnetic storms can impact infrastructure in near-Earth orbit and on Earth's surface, potentially disrupting communications, the electric power grid, navigation, radio and satellite operations," NOAA said. "[The Space Weather Prediction Center] has notified the operators of these systems so they can take protective action."

Dahl agreed Friday that the event is "pretty extraordinary" and said that it could impact infrastructure, including high-voltage transmission lines of the power grid. Dahl said that infrastructure operators have been notified to adequately prepare. 

This is the first time a storm watch has been issued for a G4 since January 2005. There is an average of 100 severe geomagnetic storms every solar cycle, but so far, there have only been three observed in the most recent cycle that began in December 2019. The most recent occurred on March 23. 

• National Oceanic and Atmospheric Administration

Li Cohen is a social media producer and trending content writer for CBS News.

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Architectural Wonders: 20 World's Fair Buildings That Stand the Test of Time

Posted: May 16, 2024 | Last updated: May 16, 2024

The Czech Eiffel Tower: The Křižíkova Fountain in Prague

These architectural marvels are not just landmarks but reflections of the host country's cultural identity. From grand pavilions to futuristic structures, each building tells a unique story through its size, shape, and architectural style. Step into a world of exhibitions, performances, and conferences that once graced these buildings during the fairs, drawing visitors from far and wide. Discover the fascinating journey of these buildings post-fair, as some find new purposes, others become historical landmarks, and a few even embark on journeys to new destinations. Join us as we explore 20 world's fair buildings that continue to captivate and inspire audiences today!

The Křižíkova Fountain was designed by the Czech engineer František Křižík and was built for the 1891 Prague Industrial Exhibition. The fountain was not just a display of water and light; it featured intricate water jets, colorful lighting effects, and synchronized music performances. Its grandeur and beauty left spectators in awe, earning it the title of the "Czech Eiffel Tower."

In 1891, the fountain used 26 arc lamps as well as 50 water jets. The fountain was renovated almost 100 years later and opened to the public on May 15th, 1991. Today, the Křižíkova Fountain is used for short-term events, such as concerts, shows, and plays. The fountain uses 1,300 lights, almost 3,000 water jets, and 49 water pumps.

Seattle's Famous Observation Tower: The Space Needle

The Space Needle was designed by architect John Graham and built for the 1962 Seattle World's Fair, also known as the Century 21 Exposition. This futuristic tower was designed to represent innovation and progress, reflecting the Space Age optimism at the time.

At 605 feet, the Space Needle quickly became the centerpiece of the Seattle World's Fair, offering visitors breathtaking views of the city and the surrounding Puget Sound region from its observation deck. Its unique saucer-shaped design was inspired by the idea of a flying saucer.

After the fair, the Space Needle continued to attract visitors from around the world. Today, the building welcomes over a million visitors annually. You can ride its elevators to the observation deck to enjoy panoramic vistas of the city, dine in the revolving restaurant, and experience the glass-floored observation deck.

An Art Nouveau Masterpiece: The Palace of Fine Arts in San Francisco

The Palace of Fine Arts in San Francisco was designed by architect Bernard Maybeck. Built for the 1915 Panama-Pacific International Exposition (PPIE), it was supposed to be a temporary structure to showcase art and culture from around the world.

The Palace of Fine Arts was the focal point for the PPIE, a world's fair commemorating the completion of the Panama Canal and celebrating San Francisco's recovery from the devastating 1906 earthquake. Its Greco-Roman design, complete with colonnades, rotundas, and a lagoon, provided a beautiful setting for exhibitions, performances, and cultural events during the fair.

Despite being intended as a temporary exhibition space, the city decided to keep the Palace of Fine Arts due to its popularity. After the fair ended, the building and its environs were restored. Today, it is a landmark in San Francisco's Marina District, attracting over a million visitors annually.

A Palace on Top of a Hill: The Montjuïc National Palace in Barcelona

The Montjuïc National Palace was built for the 1929 International Exposition, also known as the Barcelona International Exposition. Designed by architects Eugenio Cendoya and Enric Catà, it was built on top of the Montjuïc hill overlooking Barcelona, Spain. The primary purpose of the Montjuïc National Palace was as the main pavilion for the exposition, showcasing Spain's cultural heritage and technological advancements. The neoclassical design featured columns, ornate façades, and large courtyards.

During the 1929 International Exposition, the palace held exhibitions, conferences, and cultural events. Today, the Montjuïc National Palace continues to be a prominent landmark in Barcelona, attracting countless visitors who come to admire its architecture and explore the surrounding Montjuïc Park. The palace also houses the National Art Museum of Catalonia (MNAC), which exhibits an extensive collection of Catalan art spanning from the Romanesque period to the present day.

One of the Most Recognizable Structures in the World: The Eiffel Tower

The Eiffel Tower, an iconic symbol of the city of Paris and one of the world's most recognizable landmarks, was designed by French engineer Gustave Eiffel. Completed in 1889, it was built as the centerpiece of the 1889 Exposition Universelle held in Paris to commemorate the 100th anniversary of the French Revolution. At a height of 1,063 feet, the Eiffel Tower was initially met with skepticism and criticism, but it soon became a beloved landmark.

Today, the Eiffel Tower continues to attract millions of visitors annually, making it one of the most visited paid monuments in the world. Besides being a world's fair building, it now signifies something much greater: romance, adventure, and French culture. Tourists flock to the Eiffel Tower to go up its elevators and staircases, capturing photographs of the structure itself as well as the views it offers.

A Landmark No More: The Crystal Palace in London

The Crystal Palace was designed by Sir Joseph Paxton, an English gardener and architect. Situated in London's Hyde Park, it was completed in 1851 to house the Great Exhibition, the world's first international exposition of industry, culture, and innovation.

Built primarily of iron and glass, the Crystal Palace was intended to symbolize the advancements of the Industrial Revolution. Its interior space accommodated thousands of exhibits from around the world, ranging from machinery and technology to art and artifacts, attracting millions of visitors during the Great Exhibition.

While the original Crystal Palace was destroyed by a fire in 1936, its legacy lives on. Today, the site of the Crystal Palace hosts various events, including exhibitions, concerts, and sporting competitions, attracting many visitors to the Hyde Park area every year.

A Residential Experiment: Habitat 67 in Montreal

Designed by architect Moshe Safdie, Habitat 67 in Montreal was designed as a solution to urban housing challenges, exploring different ideas for affordable, high-density living in urban environments. Safdie's design for Habitat 67 has a series of interconnected concrete modules, forming a unique residential complex. Each module provides residents with spacious living quarters, private balconies, and natural light. During Expo 67, Habitat 67's bold design focused on changing urban housing and experimenting with new ideas, especially with residential architecture.

Today, Habitat 67 still attracts visitors and is an in-demand residential address in Montreal. Public tours started again in 2022, and visitors can sign up for summer tours from July to October 31st.

Peace Through Understanding and the Unisphere in Flushing, Queens

The Unisphere, in Queens, New York City, was designed by American architect Gilmore David Clarke for the 1964-1965 New York World's Fair. At 140 feet tall, this large aluminum and stainless-steel globe symbolized the fair's theme, "Peace Through Understanding." The Unisphere represented a hope for a peaceful future, and the three rings encircling the globe symbolize the orbits of Yuri Gagarin, the first human in space, John Glenn, the first American to orbit the Earth, and Telstar, the first communication satellite.

In 2010, the Unisphere was renovated with a fresh coat of paint. The Unisphere remains a landmark in Flushing Meadows-Corona Park, attracting tourists and locals who come to admire its beauty and learn about its history.

Serenity in the Middle of Urban Chaos: The Nepalese Peace Pagoda in Brisbane

The Nepalese Peace Pagoda in Brisbane City, Australia, was designed by Japanese architect Moktan Yukio. Built in 1988, the Peace Pagoda is a symbol of peace, harmony, and cultural exchange between Nepal and Australia.

The Peace Pagoda was built as part of Brisbane's Expo '88, a world exposition that celebrated Australia's bicentennial and showcased cultural diversity and innovation from around the globe. Representing Nepal's rich cultural heritage, the pagoda was a place of reflection and contemplation during the expo, fostering understanding and goodwill among visitors.

Today, the Nepalese Peace Pagoda attracts visitors looking for tranquility and spiritual solace. Its ornate architecture, adorned with intricate carvings and colorful paintings, offers a glimpse into Nepalese craftsmanship and religious traditions. Set against the backdrop of the Brisbane River and parklands, the Peace Pagoda provides a setting for meditation, cultural events, and community gatherings. The Nepalese Peace Pagoda remains a cherished landmark in Brisbane.

The Futuristic, Modernist Building: The Atomium in Brussels

The Atomium, in Brussels, Belgium, was designed by engineer André Waterkeyn and architects André and Jean Polak. Built for the 1958 Brussels World's Fair (Expo 58), the Atomium represented scientific progress, technological innovation, and the peaceful use of nuclear energy.

The Atomium featured nine interconnected spheres, each measuring 18 meters in diameter. The spheres were supposed to represent an iron crystal magnified 165 billion times. During Expo 58, the Atomium was a central attraction, offering visitors an immersive and educational experience. Its interior offered exhibitions on science, industry, and culture while its observation decks provided panoramic views of Brussels and the surrounding landscape.

Although the Atomium was originally intended as a temporary exhibit, the building still stands and continues to be a major tourist destination, attracting over half a million visitors annually. Visitors can see the exhibitions, including displays on the history of the Atomium and temporary art installations. The Atomium's observation decks are also popular, offering breathtaking views of Brussels.

Vancouver's Convention Center: Canada Place

Canada Place, a waterfront landmark in Vancouver, British Columbia, was designed by architect Eberhard Zeidler. Completed in 1986, it was built to serve as the Canadian Pavilion for Expo 86, Vancouver's World Exposition on Transportation and Communication.

The design of Canada Place is inspired by Canada's maritime heritage, with its distinctive roof resembling the sails of a ship. The complex includes the iconic five white sails, a hotel, offices, and retail spaces. Canada Place also features an outdoor promenade and the Canadian Trail, with flags representing each province and territory.

Today, Canada Place is home to the Vancouver Convention Center. It hosts conventions, trade shows, concerts, and cultural events throughout the year. With its waterfront location and panoramic views of the city skyline and mountains, Canada Place welcomes millions of visitors annually.

From Chicago to Maine: The Maine State Building

The Maine State Building was designed by Maine architect George Henry Desmond. Built for the 1893 World's Columbian Exposition held in Chicago, the building was designed to showcase Maine's rich cultural heritage, natural resources, and economic opportunities.

The building was constructed to represent Maine's presence at the world's fair, highlighting the state's contributions to industry, agriculture, and tourism. The Maine State Building boasted intricate woodwork, rustic charm, and elements of Maine's coastal heritage, including a lighthouse tower and a replica of Portland Head Light. All the materials came from Maine.

During the World's Columbian Exposition, the Maine State Building was a focal point for visitors hoping to learn about Maine's industries, products, and scenic beauty. It also provided a platform for promoting trade, tourism, and investment in the state.

The original Maine State Building in Chicago no longer exists. The building was moved to Poland Springs, Maine in 1894. Today, the building is owned by the Poland Spring Preservation Society and offers local exhibits.

The Building That Was Shipped to Chicago Piece by Piece: The Swedish Pavilion

The Swedish Pavilion was designed by Swedish architect Gustaf Clason for the 1893 World's Columbian Exposition in Chicago. This grand structure was built to showcase Sweden's cultural heritage, artistic achievements, and industrial prowess on the world stage.

The Swedish Pavilion blended different architectural styles, combining elements of traditional Swedish craftsmanship with modern influences. Its façade had intricate wood carvings and decorative motifs that reflected Sweden's artistic traditions. The building was constructed in Sweden and then shipped to Chicago piece by piece. The building cost $40,000 to erect. During the World's Columbian Exposition, the Swedish Pavilion promoted Swedish culture, industry, and trade. It offered exhibitions of Swedish art, handicrafts, and innovations.

The House That Was Designed to "Never Need Repairs": The Wieboldt-Rostone House

The Wieboldt-Rostone House, in Gary, Indiana, was designed by Walter Scholer in collaboration with William Heyer. Completed in 1933, the residence was built as a demonstration home for the Century of Progress International Exposition, held in Chicago in 1933-1934.

The Wieboldt-Rostone House was built to showcase the latest advancements in construction materials and techniques, particularly focusing on the use of Rostone, a patented synthetic stone product developed by the Rostone Corporation. The house featured a sleek modern design, with clean lines, geometric shapes, and innovative building materials. Although it was billed as "never needing repairs," the house started to show significant wear and tear by the 1940s. It was renovated in the 1950s.

Today, the Wieboldt-Rostone House is a historical landmark, providing a glimpse into the architectural trends of the early 20th century. While it is not open to the public for regular visits, the house occasionally hosts special events and tours. In 2022, the house was closed for an improvement project.

From Norway to Wisconsin and Back to Norway: Little Norway

Little Norway, located in Chicago, was not a permanent landmark but rather a temporary attraction built for the 1893 World's Columbian Exposition, also known as the Chicago World's Fair. Designed by a team of Norwegian architects and craftsmen, Little Norway was built to showcase Norwegian culture, heritage, and craftsmanship to the millions of visitors attending the fair.

The attraction featured replicas of traditional Norwegian buildings, including stave churches, log cabins, and farmhouses, all crafted to resemble their counterparts back in Norway. Visitors to Little Norway could experience Norwegian folk music, dance performances, and traditional crafts. They could even sample authentic Norwegian cuisine.

In 1935, the building was moved to Wisconsin and used as a public attraction. In 2015, however, Little Norway closed due to financial difficulties. Finally, in 2017, the building was moved to Norway.

A Building "By the French Republic to the Glory of French Art": The Grand Palais

The Grand Palais was designed by a trio of architects - Henri Deglane, Albert Louvet, and Albert-Félix-Théophile Thomas. It was constructed for the 1900 Exposition Universelle, the world's fair that celebrated the dawn of a new century.

Located on the Avenue des Champs-Élysées, the Grand Palais showcased French art, culture, and technological prowess, with its imposing iron and glass structure serving as the perfect backdrop for the displays of innovation and creativity. During the world's fair, it hosted exhibitions on art, industry, and science.

Today, the Grand Palais has become a cultural hub in the heart of Paris and a must-see destination on many tourist websites. It hosts a myriad of events from art exhibitions and fashion shows to concerts and sporting competitions. It attracts roughly two million visitors annually.

A UNESCO World Heritage Site: The Royal Exhibition Building, Melbourne

The Royal Exhibition Building was designed by Joseph Reed. Constructed in the late 1800s, it was built to host the 1880 Melbourne International Exhibition, a celebration of Australia's progress and achievements.

The Royal Exhibition Building was the centerpiece of the exhibition, showcasing the nation's cultural, industrial, and technological advancements. Its majestic dome had intricate ornamentation and towered over the surrounding Carlton Gardens. After the 1880 Melbourne International Exhibition, the building hosted the Centennial International Exhibition in 1888 and the opening of the first Parliament of Australia in 1901. It has also hosted numerous exhibitions, trade shows, and cultural events.

In 2004, it was categorized as a UNESCO World Heritage Site. As it is located near the Melbourne Museum, it now hosts events largely tied to the Melbourne Museum. Visitors can also take guided tours.

An International Museum in the Midwest: Saint Louis Art Museum in Missouri

The Saint Louis Art Museum is a cultural treasure in the heart of Forest Park in St. Louis. Designed by architect Cass Gilbert, the building was constructed for the 1904 Louisiana Purchase Exposition, also known as the St. Louis World's Fair.

The Saint Louis Art Museum was built to showcase a vast collection of artworks from around the world during the world's fair, highlighting the city's commitment to arts and culture. Its neoclassical façade and grand interior spaces provided the perfect backdrop for visitors to immerse themselves in the beauty and creativity of a variety of art exhibitions.

Today, the Saint Louis Art Museum offers an extensive collection that spans thousands of years and attracts about half a million visitors every year.

Pink and Flamboyant: The Florida Tropical House

The Florida Tropical House was designed by architect Robert Law Weed and constructed for the 1933-1934 Century of Progress International Exposition, also known as the Chicago World's Fair. The building boasted a unique blend of art deco and tropical architectural styles and is located in Beverly Shores, Indiana. Set against the backdrop of Lake Michigan, this pink waterfront house gave visitors an idea of what living in Florida was like.

Indiana Landmarks leased the home from Indiana Dunes National Park and then subleased it to tenants who would renovate it. The beachfront property boasts four bedrooms, four bathrooms, and over 3,400 square feet of space. In January of 2024, the home was listed on the market for $2.5 million, for a 52-year lease.

A Dutch Building in the Center of Massachusetts

The Dutch House was built for the 1893 World's Columbian Exposition in Chicago, Illinois, serving as a showcase of Dutch heritage and craftsmanship. Designed by architect A. D. Seymour, the residence was built to replicate the 1591 Franeker Town Hall in Friesland. It featured a distinctive gambrel roof, wooden clapboard siding, and ornate gables with decorative trim. Its interior had antique furnishings and Dutch-inspired decor.

During the world's fair, Captain Charles Brooks Appleton of Brookline became enchanted with the building. After the fair ended, he purchased the building and moved it to Brookline, Massachusetts. Today, the Dutch House is used as a multi-unit residential building.

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