Posted on 01/29/2021 12:32:34 PM PST by Red Badger
No one has yet managed to travel through time – at least to our knowledge – but the question of whether or not such a feat would be theoretically possible continues to fascinate scientists.
As movies such as The Terminator, Donnie Darko, Back to the Future and many others show, moving around in time creates a lot of problems for the fundamental rules of the Universe: if you go back in time and stop your parents from meeting, for instance, how can you possibly exist in order to go back in time in the first place?
It's a monumental head-scratcher known as the 'grandfather paradox', but in September last year a physics student Germain Tobar, from the University of Queensland in Australia, said he has worked out how to "square the numbers" to make time travel viable without the paradoxes.
"Classical dynamics says if you know the state of a system at a particular time, this can tell us the entire history of the system," said Tobar back in September 2020.
"However, Einstein's theory of general relativity predicts the existence of time loops or time travel – where an event can be both in the past and future of itself – theoretically turning the study of dynamics on its head."
What the calculations show is that space-time can potentially adapt itself to avoid paradoxes.
To use a topical example, imagine a time traveller journeying into the past to stop a disease from spreading – if the mission was successful, the time traveller would have no disease to go back in time to defeat.
Tobar's work suggests that the disease would still escape some other way, through a different route or by a different method, removing the paradox. Whatever the time traveller did, the disease wouldn't be stopped.
Tobar's work isn't easy for non-mathematicians to dig into, but it looks at the influence of deterministic processes (without any randomness) on an arbitrary number of regions in the space-time continuum, and demonstrates how both closed timelike curves (as predicted by Einstein) can fit in with the rules of free will and classical physics.
"The maths checks out – and the results are the stuff of science fiction," said physicist Fabio Costa from the University of Queensland, who supervised the research.
The new research smooths out the problem with another hypothesis, that time travel is possible but that time travellers would be restricted in what they did, to stop them creating a paradox. In this model, time travellers have the freedom to do whatever they want, but paradoxes are not possible.
While the numbers might work out, actually bending space and time to get into the past remains elusive – the time machines that scientists have devised so far are so high-concept that for they currently only exist as calculations on a page.
We might get there one day – Stephen Hawking certainly thought it was possible – and if we do then this new research suggests we would be free to do whatever we wanted to the world in the past: it would readjust itself accordingly.
"Try as you might to create a paradox, the events will always adjust themselves, to avoid any inconsistency," says Costa. "The range of mathematical processes we discovered show that time travel with free will is logically possible in our universe without any paradox."
The research has been published in Classical and Quantum Gravity.
A version of this article was first published in September 2020.
” time travel is possible but that time travellers would be restricted in what they did, to stop them creating a paradox.”
Restricted by what mechanism?
Gov, You asked, “ Now where did I put that flux capacitor???”
If you can’t find it, you can buy one here https://www.oreillyauto.com/flux-500.html
1960 JKF vs Nixon
Everyone travels through time, we just are only able to travel in one direction.
That is from a Stephen King movie.
Particularly since no matter what the hero did the timeline went on exactly as it had before.
Saw an episode of Twilight Zone where woman go back in time to kill Hitler as an infant.
Found it!
https://www.youtube.com/watch?v=byIkAPRnWnU
Oh shoot, he forgot to carry the 4 somewhere still, didn't he.
There was once a young lady named Wight,
Whose speed was much greater than light.
She went out one day.
In a relative way,
And returned on the previous night.
I wonder if the paradocs applies to Jill Biden?
Possibly not.
If they made a change that prevented themselves from existing, nope...
“Okay, let’s go back to November 2nd”
What good would that do. There were plenty of people warning of the impending fraud and doom before the election. Those people were called kooks. And nothing has changed.
In fact it is the reason that conservatives lose again and again. Because they follow the same stupid pasterns. They are not proactive they are only reactive. This allows their enemy to always beat them.
Even Trump was such a fool as to do nothing meaningful to stop the election from being stolen.
Of course, it's a Millennial. And THIS is how he chooses to spend his time and energy.
Dude! 🤗
Hey, he's getting all of it back when he goes back in time.
I have to give the GOP in California some credit.
After having at least five House seats stolen from them in 2018 because of ballot harvesting by the RATS, the GOP beat them at their own game by using ballot harvesting to get those seats back in 2020.
You have to fight fire with fire.
I always wanted to meet Ben Franklin and hand him a bic lighter and a ballpoint pen. 😊
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