No one has yet succeeded in time travel – at least to our knowledge – but the question of whether such a feat would be theoretically feasible continues to impress scientists.
As movies like The position or the terminatorAnd the Donnie DarkoAnd the Back to the future And many others show that moving in time creates a lot of problems for the basic rules of the universe: If you went back in time and prevented your parents from meeting, for example, how would you be there to go back in time in the first place?
It’s an enormous scratch known as the “grandfather paradox,” but now physics student German Tobar, from the University of Queensland in Australia, says he’s figured out how to “square numbers” to make time travel possible without paradoxes.
“Classic Dynamics says if you know the state of a system at a certain time, this can tell us the history of the entire system,” Tobar says.
However, Einstein’s theory General Relativity He predicts the existence of time loops or time travel – where an event can be in the past and the future in itself – theoretically turning the study of dynamics upside down.
What the calculations show is that spacetime can adapt itself to avoid paradoxes.
To use a positional example, imagine a time traveler traveling back in time to prevent the spread of disease – if the mission was successful, the time traveler would not suffer from a disease that went back in time to defeat.
Tobar’s work suggests that disease would still evade another way, by a different path or in a different way, removing the paradox. Whatever time a traveler does, the disease will not stop.
It’s not easy for non-athletes to research Tobar’s work, but he does research its impact Deterministic processes (Without any randomness) is based on a random number of regions in a continuum of space and time, and illustrates how both are Closed temporal curves (As Einstein predicted) it could correspond to the rules of free will and classical physics.
“Mathematics is verified – and the results are material from science fiction,” Physicist Fabio Costa says From the University of Queensland that oversaw the research.
The new research is working to solve the problem through another hypothesis, which is that time travel is possible but that time travelers will be restricted in what they did, to prevent them from creating a paradox. In this model, time travelers are free to do whatever they want, but contradictions are not possible.
Although numbers may work, bending space and time to reach into the past remains elusive – the time machines that scientists have invented thus far are so high concept that they only currently exist as on-page calculations.
We might get there someday – Stephen Hawking We definitely thought it was possible – and if we did, this new research indicates that we would be free to do whatever we want the world to in the past: it will reset itself accordingly.
“Try as much as possible to create a paradox, as events will always adjust themselves to avoid any contradiction,” Costa says. “The range of maths we have discovered shows that time travel with free will is logically possible in our universe without paradox.”
The research has been published in Classical and Quantum Gravity.