Can you travel back in time?

Time travel to the past is theoretically possible in certain general relativity spacetime geometries that permit traveling faster than the speed of light, such as cosmic strings, traversable wormholes, and Alcubierre drives.
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Can we travel back in time?

The Short Answer: Although humans can't hop into a time machine and go back in time, we do know that clocks on airplanes and satellites travel at a different speed than those on Earth. We all travel in time!
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How do you travel back in time real?

  1. Time travel via speed. This is the easiest and most practical way to time travel into the far future – go really fast. ...
  2. Time travel via gravity. The next method of time travel is also inspired by Einstein. ...
  3. Time travel via suspended animation. ...
  4. Time travel via wormholes. ...
  5. Time travel using light.
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Is it possible to go back in time and change the past?

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.
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Does the past still exist?

In short, space-time would contain the entire history of reality, with each past, present or future event occupying a clearly determined place in it, from the very beginning and for ever. The past would therefore still exist, just as the future already exists, but somewhere other than where we are now present.
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Traveling Back in Time? | StarTalk



Has anyone traveled to the future?

Although many people are fascinated by the idea of changing the past or seeing the future before it's due, no person has ever demonstrated the kind of back-and-forth time travel seen in science fiction, or proposed a method of sending a person through significant periods of time that wouldn't destroy them on the way.
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Is time an illusion?

According to theoretical physicist Carlo Rovelli, time is an illusion: our naive perception of its flow doesn't correspond to physical reality. Indeed, as Rovelli argues in The Order of Time, much more is illusory, including Isaac Newton's picture of a universally ticking clock.
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Has a time machine been invented?

In fact, a time machine has already been built. Scientists, however, are still working on how to make it as efficient as possible, like in the Back to the Future movies.
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Is it possible to travel to the future?

Traveling into the Future

While it's not possible (yet) to travel to the future fast than the rate at which we're doing it now, it is possible to speed up the passage of time. But, it only happens in small increments of time. And, it has only happened (so far) to very few people who have traveled off Earth's surface.
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Why can't we travel to the past?

The fact that the universe is still around is ample evidence that time travel to the past is impossible. Note that we have not used any ethical or social arguments involving killing your own grandfather. Time travel to the past is forbidden by simple physics even in the absence of humans.
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Can we create a time machine?

Travelling in time might sound like a flight of fancy, but some physicists think it might really be possible. BBC Horizon looked at some of the most promising ideas for turning this staple of science fiction into reality.
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What are the rules for time travel?

The Ten Rules of Time Travel
  • If you are about to leap into the past, then it has already happened.
  • Your traveler must, in no way, be connected to the facts he or she is trying to change.
  • It's a loop. An infinite one.
  • It's a loop. ...
  • Time is memory.
  • The Bootstrap Paradox.
  • Beware the uncanny valley. ( ...
  • Forward jumps are ok.
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Are wormholes real?

Wormholes are shortcuts in spacetime, popular with science fiction authors and movie directors. They've never been seen, but according to Einstein's general theory of relativity, they might exist.
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Who found time machine?

The idea of a time machine was popularized by H. G. Wells' 1895 novel The Time Machine.
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Does the present exist?

In fact, mathematically, we define the now as a single point in time. This point is an abstraction and, believe it or not, it has no duration. Ergo, mathematically, the present is a point in time with no duration: the present doesn't exist!
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Can time be stopped?

The simple answer is, "Yes, it is possible to stop time. All you need to do is travel at light speed." The practice is, admittedly, a bit more difficult. Addressing this issue requires a more thorough exposition on Special Relativity, the first of Einstein's two Relativity Theories.
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Can the future affect the past?

This idea that the future can influence the present, and that the present can influence the past, is known as retrocausality. It has been around for a while without ever catching on – and for good reason, because we never see effects happen before their causes in everyday life.
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Is time travel possible Stephen Hawking?

According to Stephen Hawking, time travel is possible, and not just in the way we might think. Backward time travel is not supported by Hawking's theories, because new matter (a new you) would need to be created – one existing in the past and one in the present, traveling back in time.
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Has anyone been in a Blackhole?

Fortunately, this has never happened to anyone — black holes are too far away to pull in any matter from our solar system.
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How many dimensions are there?

The world as we know it has three dimensions of space—length, width and depth—and one dimension of time. But there's the mind-bending possibility that many more dimensions exist out there. According to string theory, one of the leading physics model of the last half century, the universe operates with 10 dimensions.
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What is a white black hole?

White holes are theoretical cosmic regions that function in the opposite way to black holes. Just as nothing can escape a black hole, nothing can enter a white hole. White holes were long thought to be a figment of general relativity born from the same equations as their collapsed star brethren, black holes.
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What are the 3 rules of time travel?

Rules for Time Travelers
  • There are no paradoxes. ...
  • Traveling into the future is easy. ...
  • Traveling into the past is hard — but maybe not impossible. ...
  • Traveling through time is like traveling through space. ...
  • Things that travel together, age together. ...
  • Black holes are not time machines. ...
  • If something happened, it happened.
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How fast do you have to go to time travel?

One of the key ideas in relativity is that nothing can travel faster than the speed of light (opens in new tab) — 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.
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