Paradox-Free Time Travel Proven Possible by Physics Student

The rules of time-travel have been debated by scientists and sci-fi fans alike for years, but now a student physicist has been able to "square the numbers" to show how paradox-free time travel is theoretically possible. This means that should someone be able to time travel, the dreaded butterfly effect might not be as inevitable as has been feared -- but that doesn't mean a time-traveler might not still face unintended consequences. In a peer-reviewed paper published in Classical and Quantum Gravity, University of Queensland student, Germain Tobar, collaborating with the university's physics professor Fabio Costa, mathematically discovered how, "time travel with free will is logically possible in our universe without any paradox.” The math involved in all this is enough to make Will Hunting scratch his head but Tobar, like a different Matt Damon character, has been able to "science the shit" out of theorizing how one could travel through time without causing those pesky logical paradoxes that bedevil many a science-fiction protagonist. [ignvideo url="https://www.ign.com/videos/2019/04/27/explaining-the-most-complicated-part-of-avengers-endgame"] One such example is the so-called grandfather paradox wherein, as their paper puts it, "a time traveller could kill her own grandfather and thus prevent her own birth, leading to a logical inconsistency." Or, someone going back in time to prevent the COVID-19 pandemic from happening would then nix the very reason why they ever traveled through time. Yes, it's like those arguments about time travel in Avengers: Endgame all over again! “This is a paradox – an inconsistency that often leads people to think that time travel cannot occur in our universe," Costa said. "Some physicists say it is possible, but logically 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.” Tobar basically said, hold my beer and went about proving that, theoretically, one can travel through time, exert free will, and not create any such logical paradoxes. Because classical dynamics and Einstein's Theory of Relativity are at odds with each other on the matter, Tobar's paper calculated how closed time-like curves (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." Or, as Popular Mechanics succinctly puts it, "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." [widget path="global/article/imagegallery" parameters="albumSlug=the-best-sci-fi-movies-on-netflix&captions=true"] Tobar's calculations show how theoretically one could time-travel and exert free will in a way that wouldn't prevent the reason why they went back in time. But it could make them wish they had never time-traveled to begin with:

"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."

In the words of those venerable time travel experts Bill S. Preston, Esq. and Ted "Theodore" Logan: bogus! For more science coverage, learn about the possibility of life on Venus, evidence of a parallel universe where time runs backward, why the moon is rusting, and the discovery of underground lakes on Mars.

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