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A Scientist Proved Paradox-Free Time Travel Is Possible
Popular Mechanics ^ | July 11, 2025 | Caroline Delbert

Posted on 10/24/2025 8:44:59 PM PDT by Red Badger

Here’s what you’ll learn when you read this story:

* Time travel is deterministic and locally free, a paper says—resolving an age-old paradox.

* This follows research observing that the present is not changed by a time-traveling qubit.

* It’s still not very nice to step on butterflies, though.

=======================================================================

In a peer-reviewed paper, a scientist says he has mathematically proven the physical feasibility of a specific kind of time travel. The paper appears in Classical and Quantum Gravity.

Germain Tobar and Fabio Costa, both of the University of Queensland at the time of the paper’s publication, worked together on the study. In “Reversible dynamics with closed time-like curves and freedom of choice,” Tobar and Costa say they found a middle ground in mathematics that solves a major logical paradox in one model of time travel. Let’s dig in.

The math itself is complex, but it boils down to something fairly simple. Time travel discussion focuses on closed time-like curves (CTCs), something Albert Einstein first posited. And Tobar and Costa say that as long as just two pieces of an entire scenario within a CTC are still in “causal order” when you leave, the rest is subject to local free will.

“Our results show that CTCs are not only compatible with determinism and with the local 'free choice' of operations, but also with a rich and diverse range of scenarios and dynamical processes,” their paper concludes.

In a statement, Costa illustrates the science with an analogy:

“Say you travelled in time, in an attempt to stop COVID-19's patient zero from being exposed to the virus. However if you stopped that individual from becoming infected, that would eliminate the motivation for you to go back and stop the pandemic in the first place. This is a paradox, an inconsistency that often leads people to think that time travel cannot occur in our universe. [L]ogically it's hard to accept because that would affect our freedom to make any arbitrary action. It would mean you can time travel, but you cannot do anything that would cause a paradox to occur." Some outcomes of this are grouped as the “butterfly effect,” which refers to unintended large consequences of small actions. But the real truth, in terms of the mathematical outcomes, is more like another classic parable: the monkey’s paw. Be careful what you wish for, and be careful what you time travel for.

Tobar explains in the statement:

“In the coronavirus patient zero example, you might try and stop patient zero from becoming infected, but in doing so you would catch the virus and become patient zero, or someone else would. No matter what you did, the salient events would just recalibrate around you. Try as you might to create a paradox, the events will always adjust themselves, to avoid any inconsistency.” While that sounds frustrating for the person trying to prevent a pandemic or kill Hitler, for mathematicians, it helps to smooth a fundamental speed bump in the way we think about time. It also fits with quantum findings from Los Alamos, for example, and the way random walk mathematics behave in one and two dimensions.

At the very least, this research suggests that anyone eventually designing a way to meaningfully travel in time could do so and experiment without an underlying fear of ruining the world—at least not right away.


TOPICS: Education; History; Military/Veterans; Weird Stuff
KEYWORDS: amateurphilosophy; astronomy; ifhfakescience; physics; science; sffantasies; stringtheory; timetravel
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1 posted on 10/24/2025 8:44:59 PM PDT by Red Badger
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To: MtnClimber; SunkenCiv; rktman; mowowie; SuperLuminal; Cottonbay; telescope115; laplata; ...

Back to the Ping!..................


2 posted on 10/24/2025 8:45:33 PM PDT by Red Badger (Homeless veterans camp in the streets while illegals are put up in 5 Star hotels....................)
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To: Red Badger

I would like to time-travel to 2026 and return with a copy of the Wall Street Journal.


3 posted on 10/24/2025 8:48:04 PM PDT by Fiji Hill
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To: Red Badger

The paradox of trying to stop the Scamdemic?


4 posted on 10/24/2025 8:54:29 PM PDT by Deaf Smith (When a Texan takes his chances, chances will be taken that's for sure.)
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To: Fiji Hill

I’d be happy with having tonight’s winning mega millions numbers.


5 posted on 10/24/2025 8:56:38 PM PDT by RandallFlagg (Democrats should have been barred from elections since The Battle Of Athens.)
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To: Red Badger

Uh, sorry, I’m nothing going to take a collection of math equations as “proof” that paradox-free time-travel is possible. The proof of the pudding is in the eating. Someone is going to have to actually achieve time travel to prove that’s is possible.


6 posted on 10/24/2025 8:57:17 PM PDT by irishjuggler
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To: irishjuggler

*”...I’m NOT...”


7 posted on 10/24/2025 8:57:47 PM PDT by irishjuggler
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To: Red Badger

“Proved”... “You Keep Using That Word, I Do Not Think It Means What You Think It Means!”


8 posted on 10/24/2025 9:00:01 PM PDT by Nervous Tick (Hope, as a righteous product of properly aligned Faith, IS in fact a strategy.)
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To: Red Badger; bitt; little jeremiah; generally; Melian; foldspace

Heads up


9 posted on 10/24/2025 9:00:47 PM PDT by thinden (Buckle Up!)
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To: Fiji Hill

10 posted on 10/24/2025 9:02:24 PM PDT by Red Badger (Homeless veterans camp in the streets while illegals are put up in 5 Star hotels....................)
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To: irishjuggler

That it’s possible doesn’t mean it’s practical...........


11 posted on 10/24/2025 9:03:45 PM PDT by Red Badger (Homeless veterans camp in the streets while illegals are put up in 5 Star hotels....................)
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To: Red Badger
Time travel is possible, but you can only travel forward. You can leap long distances ahead but you have to return to after the point you left.
12 posted on 10/24/2025 9:05:05 PM PDT by Harmless Teddy Bear (It's like somebody just put the Constitution up on a wall …. and shot the First Amendment -Mike Rowe)
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To: Red Badger

Big deal. I proved this way back in 2047.


13 posted on 10/24/2025 9:06:53 PM PDT by ConservaTexan (February 6, 1911/June 14, 1944)
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To: Red Badger

There once was a young lady named Wright
Whose speed was much greater than light
She went out one day
In a relative way
And returned on the previous night.


14 posted on 10/24/2025 9:17:11 PM PDT by july4thfreedomfoundation (Russia? China? Democrats and RINOs are the biggest threat to the survival of America.)
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To: Red Badger

So, if I were to travel back to the 1970s, and frame Anthony Fauci for murder, he would never have totally botched the AIDS epidemic, and would have been no where near the Plandemic.

Would some other apparatchik have taken his place? Perhaps. And perhaps that other apparatchik would not have been such an accomplished liar.


15 posted on 10/24/2025 9:20:28 PM PDT by Ronaldus Magnus III (Do, or do not, there is no try )
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To: Red Badger

Or, there really is a multiverse and one is simply hopping from one reality to another. (Which would suggest that the “Big Bang” was actually a “Bigger Bang”.)


16 posted on 10/24/2025 9:53:37 PM PDT by The Duke (Not without inciden)
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To: Red Badger

Soon we’ll be sending quarks back to the Pleistocene age.


17 posted on 10/24/2025 10:02:56 PM PDT by E. Pluribus Unum (Je suis Charlie Kirk.)
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To: E. Pluribus Unum

Its true! I slept backerds one night and the next morning I woke up the day before and had to do the same day all over again. It was like deja vu all over again.


18 posted on 10/24/2025 10:09:55 PM PDT by Bob434 (Time flies like an arrow, fruit flies like a banana)
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To: Harmless Teddy Bear
Time travel is possible, but you can only travel forward.

We all do that every night. It’s called sleep. Every morning, I wake up in the future.

19 posted on 10/24/2025 10:21:45 PM PDT by noiseman (The only thing necessary for the triumph of evil is for good men to do nothing.)
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To: Red Badger
Philosophical, but still a great way to evoke a sense of 'time-travel' is a favorite quote that I like to ponder:

“Live as if you were living already for the second time and as if you had acted the first time as wrongly as you are about to act now!" It seems to me that there is nothing which would stimulate a man's sense of responsibleness more than this maxim, which invites him to imagine first that the present is past and, second, that the past may yet be changed and amended.” ― Viktor Frankl (Man's Search for Meaning)
20 posted on 10/24/2025 10:30:22 PM PDT by know.your.why
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