The possibility of time travel is often debated and theorized by laymen, but it has also garnered the attention of the titans of physics. Ever since Albert Einstein demonstrated that time dilation is a real thing, speculation has grown about the possibilities of time travel. Einstein’s work illustrated that the faster someone travels, and the closer they get to light speed, the slower time moves for that individual. All the while, time continues to move at the same pace for people on Earth. Stephen Hawking, the world renowned theoretical physicist, did not shy away from the growing speculation about time travel.
Let’s just say Stephen Hawking was a skeptic when it comes to traveling back in time. To make his point, he conducted a simple, but elegant experiment. He held a party. That’s right, in 2009, Hawking decided to host a party with balloons, hors d’oeuvres, and champagne for guests willing to travel back in time for the party. Hawking told reporters, “I gave a party for time-travelers, but I didn’t send out the invitations until after the party. I sat there a long time, but no one came.”
The Discovery Channel was there to capture the event at the University of Cambridge, in the event that someone happened to arrive. Hawking even made sure to provide precise GPS coordinates, just in case someone became lost through space time.
9. Time Machines
Although Hawking was immensely skeptical of the possibility about traveling back in time, he was willing to engage in the notion. According to Mr. Hawking, everything including time itself has wrinkles and voids in it; there are tiny tunnels in the quantum world that form, disappear, and reappear. Theoretically, they would link separate places and, most importantly for time travelers, time.
However, these wrinkles and voids on the quantum level are far too small for a human to pass through. A time machine that wanted to attempt such a feat would need to capture and enlarge a wormhole enough so that a spaceship could travel through it. If such a device were to built, Hawking said, “One end could be here near Earth, and the other far, far away, near some distant planet.”
8. Time Travel into the Past May Be Impossible
After his theorizations, Hawking concluded that traveling back in time is probably impossible. He believed that the wormhole would create paradoxes that would prevent it from being created in the first place. For example, a person traveling back in time and killing themselves before the creation of the time machine.
More importantly, Hawking argued that natural radiation would seep into the wormhole and the resulting feedback would be so strong that the wormhole, and thus the time machine, would be destroyed. He went even further, suggesting that the creation of such a device may have dire effects. Hawking believed it may trigger a bolt of radiation that would not only destroy the time traveling spaceship, but space time itself.
7. Traveling into the Future
Although Hawking didn’t believing traveling back in time is possible, he did believe that traveling into the future is possible. An example he cites is the Earth’s mass dragging on time. If the Earth was approaching a black hole, time would slow down for people and the force of gravity would increase. Naturally, a black hole is a dangerous method so Hawking proposed the potential of traveling near the speed of light.
As one nears the speed of light, Hawking argued, time would slow down in order to protect the speed, and also to make it physically impossible to ever break it. Therefore, Hawking believed, “that a human traveling near the speed of light could reach the end of the galaxy within their lifetime.”
6. The Spaceship
The fastest manned spaceship was the Apollo 10, and it climbed to a speed of 25,000 mph. In order for time travel to be possible, humans would have to design a spaceship that travels 2,000 times the speed of the Apollo 10. That’s… that’s pretty fast, you guys.
It will also need absurd amounts of fuel to make it through a wormhole while not sacrificing any of its speed. It’s unlikely that even Elon Musk will be able to accomplish this feat in the coming years, but someday it’s certainly a possibility.