Ker Than for National Geographic News
Published April 12, 2013
Actor Rod Taylor tries to fast forward in the 1960 film The Time Machine.
Photograph from Metro-Goldwyn-Mayer/Getty Images
It’s not quite Back to the Future, but a young Iranian inventor claims to have built a time machine that can predict a person’s future with startling accuracy.
Ali Razeqi, who is 27 and the “managing director of Iran’s Center for Strategic Inventions,” claims his device will print out a report detailing an individual’s future after using complex algorithms to predict his or her fate.
According to the Daily Telegraph, Razeqi told Iran’s state-run Fars news agency that his device “easily fits into the size of a personal computer case and can predict details of the next 5-8 years of the life of its users. It will not take you into the future, it will bring the future to you.”
Razeqi says Iran has decided to keep his prophetic time machine under wraps for now out of fear that “the Chinese will steal the idea and produce it in millions overnight.”
Iran’s Deputy Minister of Science, Research, and Technology dismissed Razeqi’s claims on Friday in an interview with Fars—a sign of just how much attention the story has received.
We talked to Thomas Roman, a theoretical physicist at Central Connecticut State University and a co-author of the book Time Travel and Warp Drives, to ask about the possibilities for a Razeqi-like time machine and to debunk popular misconceptions about time travel. Here’s an edited version of our interview:
What do you think of Razeqi’s claim that he’s built a time machine that can predict a person’s future?
It’s completely nuts.
Does his alleged time machine break any laws of physics?
It’s hard to know because it’s so wacky.
What are some popular misconceptions about time travel?
One popular misconception is that you could go back to any time in the past. And that’s not true. You can only go back as far as the time when the time machine was invented. So if I invent my time machine today and I wait 30 years and go back to the past, the farthest back in the past I can go to is today when I turned my time machine on.
Another major misconception—and you see this a lot in time travel movies—is the idea that you can go back in time and change the timeline. In these stories, the time traveler goes backward in time and does something that mucks up the future and subsequently has to do something to “restore the timeline.” However, that can’t be the case, since we can’t have the same event both happen and not happen in the same universe. You can’t change the past.
For example, suppose I go back in time and try to kill my grandfather. If I succeed, then of course I’m never born and I could never have made the trip back using the time machine.
Once again, we can’t have the same event—the killing of my grandfather—both happen and not happen in the same universe.
Is there any way of getting around this “grandfather paradox”?
There are two possibilities. One is what’s sometimes called the self-consistency scenario, in which all events along the time loop that I make are adjusted to be self-consistent.
So for example, if I go backward in time and try to shoot my grandfather, something will always prevent me from doing so. The recoil on my shoulder makes me miss, or my grandfather ducks, or I change my mind. It’s like the universe and the laws of physics are conspiring to make things consistent.
The other possibility is that when I shoot my grandfather the universe splits and there’s one universe in which I shoot my grandfather and there’s another universe in which I did not shoot my grandfather.
Didn’t split timelines play a role in the latest Star Trek reboot by J. J. Abrams?
Yeah, there was something along those lines. In the movie, the Romulan bad guy Nero goes back to the past to get revenge against Spock, who he claims is responsible for the destruction of his home planet Romulus. So he’s going to get even by going back into the past to destroy [the planet] Vulcan.
But since Vulcan wasn’t destroyed in the original timeline—the one Nero came from—then upon going back into the past, he causes the universe to branch.
So the Vulcan he destroys is not the one in his original timeline, but the one in the new branch. So he’s not really getting revenge on the original Vulcan from his timeline. But I suppose revenge is revenge.
That aside, I thought that [using the concept of a split timeline] was a clever way of rebooting the franchise because then you have the same characters but you don’t have to slavishly follow the past history of the episodes since you’re in a new timeline where everything can be different.
Okay, so you might not be able to travel to the past. But is future time travel possible?
There’s no problem with that. In fact, we know how to do it in principle. If you travel very close to the speed of light, time slows down for the space traveler compared to someone on Earth.
Another way of traveling to the future is by orbiting very close to a black hole. For example, if you orbit around the black hole at the center of our galaxy, you could also have your time stretched relative to observers on the Earth.
If future time travel is possible, then could a time machine like the one the Iranian businessman claimed to have built actually work?
Going to the future is no problem. A mechanism for traveling into the future is afforded by [Einstein’s] special theory of relativity. It’s when you try to go backward that you run into the grandfather paradox. However, that said, what the businessman claims to have built is still nuts.
One thing that’s rarely mentioned in time travel stories is that if you travel back only in time but stay in exactly the same point in space, the Earth won’t be there anymore. So wouldn’t time travel require traveling through space as well?
Yes, it would have to. The Earth is turning on its axis, and it’s orbiting the sun. So the Earth isn’t always in the same spot in its orbit. So if you’re staying in the same place and traveling back to the past, the Earth is gone from underneath you. When you stop your time machine, you’ll be in a bit of a pickle.
Why do you think time travel is so popular in books and movies?
You have to admit, it’s a pretty tantalizing idea. Part of the appeal is that you can go back and see things for yourself that you only know through history books and the geological record. I think everybody would think it’d be really cool to go back and see dinosaurs or go back and visit ancient Greece.
I think another appeal is we all have things in our past that we wished that we hadn’t done, or that we wished hadn’t happened. And I think there’s the desire to be able to go back and prevent those things from having happened.