Can a time traveler change the past? If so, then the universe seems to have an unknown power that can change events.
A new study from the University of Queensland suggests that it is not possible to go back in time and change the events of the past. Even if time travel is possible, a bizarre chain of events can change the timeline. It’s like the plot of a sci-fi movie, but it could be real.
Speaking in a video for The Hill, National Science Foundation program director and astrophysicist Joe Pesce discussed new research on Einstein’s general theory of relativity.
Pesce, who noted that he doesn’t believe time travel will become a reality, said: “The timeline rearranges itself. It self-corrects to avoid any paradox.”
Using COVID-19 as an example, he suggested that if the time traveler tried to stop Patient Zero from spreading the virus, then time would fix itself. So he or someone else could become patient zero and the pandemic would still happen.
Using himself as a hypothetical time traveller, Pesce explained:
“I travel back in time. If I prevent the infection of patient zero and stop the pandemic, then this will remove my motivation for traveling to the past. And that is the essence of the grandfather paradox.”
“So what these researchers found in the math is that events will recalibrate themselves. So maybe I go and stop patient zero, but then I become patient zero and start an infection.”
“Ultimately, the endpoint is still the same; the pandemic will still happen. But the specific events, maybe the details of the timeline change. So the math shows that you really can’t go back and affect the end point. The end point will always be the same and the same. We can get to it in a different way,” he said.
Notably, it remains unclear what mechanism the Universe could use to recalibrate the timeline. Wouldn’t changing events in itself be a kind of time travel? In that case, who or what is changing the chronology? This is interesting to think about.
