The concept of time travel has long captivated the human imagination, inspiring countless films and theories. But a 2020 study led by Germain Tobar, a physics student at the University of Queensland, suggests that time travel could theoretically work without creating the infamous “grandfather paradox.”
This paradox challenges the logic of time travel: if someone went back in time and prevented their grandparents from meeting, their own existence and thus the possibility of time travel would be erased. However, Tobar’s calculations indicate that the universe might naturally adapt to prevent such contradictions.
For example, if a time traveler attempted to stop a disease from spreading, Tobar’s research suggests the disease would still emerge through a different route, ensuring history remains consistent. The time traveler’s actions, while impactful, wouldn’t alter the overall outcome.
“Classical dynamics tells us that knowing the state of a system at one time can predict its entire history,” explained Tobar. “But Einstein’s theory of general relativity allows for time loops, where events can exist both in the past and future of themselves.”
The research explores how deterministic processes interact within closed time-like curves, a feature of space-time predicted by Einstein. These findings show that time travel, governed by the laws of physics and free will, could avoid paradoxes altogether.
“Try as you might to create a paradox, the events will always adjust themselves to avoid inconsistencies,” said Fabio Costa, Tobar’s research supervisor.
Despite these promising calculations, the practical creation of a time machine remains far beyond current technological capabilities. While the math checks out, bending space-time to revisit the past is still confined to the realm of theoretical physics and science fiction.
Stephen Hawking once theorized that time travel could be achievable, and if it ever becomes a reality, this research suggests that the universe would naturally prevent any paradoxical outcomes. For now, time travel remains a tantalizing puzzle, with the universe itself seemingly holding the key to resolving its mysteries.