Can we 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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Is it possible to travel back in time?

Time travel is possible based on the laws of physics, according to new calculations from researchers at the University of Queensland. But time-travelers wouldn't be able to alter the past in a measurable way, they say — the future would stay the same. Visit Business Insider's homepage for more stories.
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How do you go back in time?

  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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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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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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Is a time machine possible?

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.
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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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Can we travel to future but not the past?

Quantum physics shows that there is a means of moving within our three-dimensional space without the passage of time. Scientists have been able to make particles move from one physical location to another without ever existing in-between. That's why it's called a quantum leap.
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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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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 invented time?

The Egyptians broke the period from sunrise to sunset into twelve equal parts, giving us the forerunner of today's hours. As a result, the Egyptian hour was not a constant length of time, as is the case today; rather, as one-twelfth of the daylight period, it varied with length of the day, and hence with the seasons.
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How do I build a time machine?

How to Build a Time Machine by Paul Davies is a 2002 physics book that discusses the possibilities of time travel. It was published by Penguin Books. In this book, Davies discusses why time is relative, how this relates to time travel, and then lays out a "blueprint" for a real time machine.
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What is the formula for time travel?

In fact, according to Albert Einstein's famous equation, E = mc² , time travel is possible, at least in one direction.
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Is it possible to travel at the speed of light?

Based on our current understanding of physics and the limits of the natural world, the answer, sadly, is no. According to Albert Einstein's theory of special relativity, summarized by the famous equation E=mc2, the speed of light (c) is something like a cosmic speed limit that cannot be surpassed.
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Can humans travel at the speed of light?

No, we cannot travel at the speed of light. You see, if an object travels at the speed of light, its mass will increase exponentially! Consider this… the speed of light is 300,000 kilometers per second (186,000 miles per second) and when an object moves at this speed, its mass will become infinite.
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Why does time never stop?

In order for you to stop time, you would have to be traveling infinitely fast. Nothing can travel faster than light (let alone infinitely fast) without gaining infinite mass and energy, according to Einstein's theory of relativity.
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Why do I keep wanting to go back in time?

People go through a series of difficult experiences in life that might force them to contemplate their past. During these periods of reflection or regret, they'll sometimes wish they could turn back time, either to return to “the good old days” or to undo the mistakes they've made.
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Can animals mentally time travel?

Recent behavioral experiments with scrub jays and nonhuman primates indicate they can anticipate and plan for future needs not currently experienced. Combined with accumulating evidence for episodic-like memory in animals, these studies suggest that some animals can mentally time travel into both the past and future.
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What happens to your brain when you travel?

According to University of Pittsburgh neuroscientist Paul Nussbaum, traveling can stimulate your brain and encourage the growth of new connections within cerebral matter. The key concept is the link between new experiences and the generation of dendrites within the brain.
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