Is time travel really possible? "Maybe," says Paul Davis, professor of philosophy of science at Macquarie University in Sydney, Australia. Davis is the author of the book "How to Build a Time Machine" which was published this year
By Anthony Ramirez New York Times
Rod Taylor in "The Time Machine" according to "Jules"
Of all science fiction dreams, time travel is the most delusional. Escaping time means escaping everything - history, regret and above all, death. But is time travel really possible? "Maybe," says Paul Davis, professor of philosophy of science at Macquarie University in Sydney, Australia. Davis is the author of the book "How to Build a Time Machine" which was published this year.
In the world of physics, apparently inhabited by his mind, time travel is the last cry. Some of the giants of physics, including Kip Thorne, John Wheeler (who coined the term "black hole") and the most famous physicist in the world, Stephen Hawking, have written books in recent years in which they put forward hypotheses and theories about this journey.
But it is not the theory that excites the common man, but the vision of the shiny new time machine rushing into the Jurassic era, or hovering over the Battle of Waterloo. Another idea accepted by laymen is that time is a dynamic and linear thing (like a video tape that can be moved forward or backward), while the location of objects in the world (the earth, the high school) remains fixed. Both assumptions are wrong, and voluntary time travel is fraught with complex problems even on a conceptual level.
Those who seek to go back in time face the "grandfather paradox", which raises the possibility that a time traveler will meet his own grandfather, kill him and thereby make his very existence logically impossible. The idea is that any physical movement into the past causes a change that creates the paradox. Thinking about this paradox, Hawking concluded that it is possible that nature strives to protect the order of time at all costs, and as he said, to make the universe a "safe place for historians".
There is also the perception that sees time as a kind of video tape. A time traveler who jumps many years into the future will find that the earth, the sun - everything - have continued to move through space. If he asks to retrace his steps to the original time from which he left, he may return to the correct date, but to a completely different place.
The most disappointing thing for science fiction fans is that Davis' time machine will not resemble a fancy DeLorean, like the one Michael J. Fox drove in the Back to the Future movies. As strange as it sounds, it will more closely resemble a mine shaft.
If the universe is curved, as we will see, then crawling along its surface is progress in the long way. A much shorter route would be obtained by traveling in a mine shaft through the surface, like a hole made by a worm burrowing into an apple. Physicists call such a hole in space, similar to a black hole, a "wormhole". If wormholes do exist, they could serve as short-cut routes to travel between different parts of the universe and time.
After all, from the theory of relativity it follows that time and space are the same thing - one thing known as time-space. A wormhole through space is therefore a wormhole through time - and here you have a time machine. Of course, as in the case of black holes, the traveler will have to survive passing through the enormous gravitational field of the wormhole.
Regarding this problem and others, Davis offers explanations that are encouraging in their accuracy. For example, a heavy ion accelerator is an essential component. But in general his time machine is inconceivable to anger.
Much of modern technology revolves around the invisible. Power plants and their networks generate, amplify and transmit electrical energy, for example. Davis's proposed time machine would be a method for detecting, amplifying and stabilizing wormholes, assuming they exist.
But it is not only that this machine does not exactly meet the expectations of the average person - its capacity also falls short of what is desired. The journey into the past will be problematic, while the journey into the future will be very dangerous. The enormous gravitational field of the wormhole might, for example, tear the traveler apart. According to Davis, "It's going to be a wild ride."
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20 תגובות
But you don't understand what all the scientists are saying...
If we can't reach other universes, or we
They can and it simply involves risk, apparently nature wanted only for our benefit
Oh and by the way, how come you haven't already met people from the future?
If anything, I think that the singer George Michael is from the future, as it were
What are all these stories: Dad sells shawarma, in his childhood
A fat and nerdy boy, gay, mother died of cancer, same voice as Kylie's
Minogue is just slower and he also has horrible accidents and not
Nothing happens to him! Something is strange here...
Can't figure out what the fuss is between the theory of relativity and the fact that it doesn't make sense to change things in the past?! This is fucking science fiction!!!
I read a lot about time travel, general relativity, etc... all theoretical topics!! How do you try to invent a machine in practice and you answer questions as illogical for reasons that the operation cannot be performed?! It is clear that it will not be possible to carry out the operation because the subject itself is theoretical and contradicts reality!! In addition, I do not manage to clearly understand how to go back in time? After all, it's only relative, for example, a body moves fast, so time becomes slower.. this does not mean that time is really slower!! Time just seems slower... so how can you go back in time if the repetition is as if... and the speeds of light in relation to other objects only create a false effect of going back in time or the lengthening of time?!? Please answer urgently, I'm trying to understand the matter!!!
Or yes and 1 how the hell are you going to put the telescope light years away from God and even if so only the transmission of the information from it will take longer than the time you want to watch it you will have to calculate the transmission time and until you receive the first transmission it will take years (provided it is strong enough)
If you move back in time and change what you want…
It won't mean that you won't have to change it and then you actually didn't go back to change it and it will go back to the way it was
It's bizarre to change the past and even if you change the future it won't affect what you are now and once again everything will be back to normal
PS: I have a question. Has anyone else noticed that in Doctor Who Rose doesn't see her boyfriend for a year but she has a time machine...
She could have just returned from the travels to a time that was only a few seconds/days after they broke up... I say FAIL to that
12 Do you want to build a time machine?!
It's a shame that the article doesn't explain how the time machine is described in the book and how it's built, and not just what the machine can't do
I'm sure you can go back in time! Surely all the kidnappings that happen are kidnappings by people from the future! In short, as they say "we'll live and see"……..
in ballets
A. Ben-Ner
In my humble opinion, what or who travels to the past does not experience anything unusual - he simply suddenly finds himself in the past, therefore nothing will change in the experiences, the disintegration will be as it was and cause and effect will not change.
I have a question for those in the know.
Suppose we succeed in inventing a "time machine" that will allow "travel" back in time.
What indication would we have that we indeed traveled back in time and not forward?
For example, suppose we measure the radioactive decay of a certain substance and suddenly in a certain time segment the rate of decay will increase instead of decrease. Will this be a sufficient indication to determine that we have gone back in time?
Another question regarding the concept of cause and effect.
Is it true that while traveling back in time
There will be an inversion of these concepts. The cause will become the result and the result - the cause.
Doesn't this contradict the laws of thermodynamics? After all, during the journey back in time, the entropy of that space-time segment will decrease and not increase.
What nonsense!!!
Anyone familiar with the U-shaped bending of space
and connect its ends by investing enormous energy or enormous mass
Can understand that it won't cause going back in time
Let's take for example a map of a table
The more mass we put on it, the more it will curve and "lower" the height of the map in that area.
The lower you are (closer to mass/energy/pressure) then the slower time passes for you.
Once we fold the map into a U shape
And we put mass/energy/pressure on it (maal) it will come closer between the ends
Even if they manage to touch each other and create a wormhole
What this means - whoever goes through the wormhole, time will slow down for him until a certain stage and then start speeding up again when he comes out the other end.
What's more, the bending of space-time in a U shape or in general a transition that is not in the 4 dimensions (time and 3 dimensions of space) is not possible (at least not in the physics we know)
We are limited to movement in 4 dimensions and we are not observers from the outside who see the bending - we live inside the bending, inside the map, which there is in 2 dimensions, for us it is 4 dimensions... it is simply easy to imagine it with a map.
So in my opinion, this is not possible at all and eliminates "cause -> effect"
Except for a hypothetical object/particle that can exceed the speed of light and even that is doubtful if it can go back in time.
Some say that antimatter moves backwards in time - but it still has an arrow of time - the causality in the future and the result in the past.
This is also a big question mark.
If you already create a wormhole it will be used to go from one place to another in 0 time, without having to go through the speed of light and even then... you need to help the map we talked about earlier in my opinion and go through dimension 5
That is, to go out of existence in 4 dimensions and reappear somewhere else.
Successfully (:
Theoretically it is possible to go back in time because they haven't researched it yet, and if they research about traveling in Zen and manage to find out how to move between times then I estimate that they will not become non-existent unless they meet their grandfather or their parents, but if that person returns 6 Years back, so if he changes something, he won't change anything about himself, but from a practical point of view they still haven't discovered how to go back in time, I wish they would find out because I'd love to go back in time to the 90s or even change things like saving the late Yitzhak Rabin and so'.
What is this small print? We don't have telescoping ships
The "grandfather" paradox as we call it, or the butterfly's return to the past as I call it, can be solved in one and only way: our journey to the past will inevitably lead us to another timeline, different from our timeline in that the possibility that we are there exists. And by the way, going back to our timeline is tenuous if not impossible and the reasons are understandable.
So if we supposedly kill our grandfather, we will kill a grandfather from another time line, which is very similar to ours, but has no effect on us. The "grandfather" paradox is an extreme version of the butterfly effect, which inevitably occurs when a small change is made in the space-time space that was not there before.
Who said we haven't met already?
If it were possible to go back in time, then we would have already met someone from the future...
I think it is impossible to go back in time or see the future, but it is possible to reach the future and see the past - things that will not endanger your very formation or change your future once you have seen it. To see the past you can place a huge telescope in space several light years away, and the number of light years will be the number of years you can look back in time.
The light will take time to reach from the earth to the telescope and this time we will be able to see backwards. This will not affect the past, which means that it will not endanger the very existence of the observer of the past. However, if he returns to the past, he will be able to change things that will cause his non-existence or non-birth.
It is also possible to reach the future, by fast movement, which causes a time difference between the fast moving object and the environment. This time difference is expressed in the fact that for the fast moving object, time will pass more slowly than in the environment and thus it will be able to reach the future.
Moving into the future will not endanger his very existence and he will not be able to see himself there (because the whole time he skipped over, he was not there (in the environment), he was busy moving quickly), in contrast to returning to the past, which has already been determined, and the same object is already there and then theoretically , he should see himself