Hello and welcome back to Life’s Biggest Questions, I’m Ron McKenzie-Lefurgey. For centuries, humanity has looked to the stars and wondered what was out there. In recent decades, space exploration has become a reality. However, if we want to really explore outside of our own solar system, we’ll need to figure out a way to travel at great speeds, maybe even faster than light. Can it be done? Let’s find out. If you want more What If videos, check out our “Biggest What Ifs” playlist on the channel. Now get ready, it’s time to ask the question: Could we Travel Faster than the Speed of Light? As was discussed in our video How Fast can Humans Go, our current understanding of physics would lead us to believe that nothing can travel faster than the speed of light. Particles with mass require energy in order to accelerate. However, as an object approaches light speed, it gains more and more mass, to the point where you would require more energy than exists in the universe to move at light speed.
So it seems that actual faster than light travel is impossible; does that mean we’ll never see the outer reaches of space? Not necessarily. There are a number of hypotheses as to how we could travel vast distances in a relatively short time. One possibility that is often put forth is using Worm Holes to travel quickly through space. While these holes haven’t actually been observed, they are theorized to exist, acting as a bridge between two points, similar to the Portal gun from the Portal games. Some theorize that we could use these holes to travel vast distances in the blink of an eye. Unfortunately, we haven’t found a way to use these holes, or even solid evidence that they exist; but that hasn’t stopped people from studying them.
A 1988 paper by Michael Morris, Kip Thorne, and Yuri Yurtsever even proposed an idea for a wormhole time machine. However, according to Stephen Hawking, keeping these holes open would require negative energy. More on that later. Another fun place to look for methods of effectively travelling faster than the speed of light is science fiction. And two of the most popular sci-fi franchises, Star Wars and Star Trek, take rather different approaches to this problem. In Star Wars, ships are outfitted with a hyperdrive. This involves a ship accelerating near light speed and entering hyperspace, an alternate dimension that can be used as a sort of shortcut between two points in physical space. This requires large amounts of calculations, as Han explains in the film. Even though the ship is physically in another dimension, large objects in physical space would cast “Mass Shadows” that could affect the ship in hyperspace. This would allow people to effectively achieve ridiculous speeds, crossing the galaxies in a matter of days. Some nerds even calculated this, and determined that the Millenium Falcon could potentially travel over 1000 light years per hour.
Unfortunately, as of now, this remains in the realm of science fiction, as we have no convincing reason to believe hyperspace exists, or that it can be used in this way. Star Trek, on the other hand, has a somewhat less impressive, but more realistic, mechanism: The Warp Drive. The Warp drive involves the manipulation of Space Time. By annihilating deuterium and antimatter, the warp drive can cause warp fields to form a subspace bubble that distorts the local spacetime continuum. This is significantly slower than the hyperdrive from Star Wars; at Warp 9.9, which is faster than most ships in Star Trek can travel, a ship can reach speeds of just light years an hour.
Very impressive, but nothing compared to the Millenium Falcon’s 1000. However, this is particularly relevant to the question, because it actually fits in somewhat with our current understanding of physics. The Warp Drive actually inspired the Alcubierre drive, posited by theoretical physicist Miguel Alcubierre. It involves a whole bunch of calculations that I’m far too stupid to understand, let alone explain, but I’ll try to give a simplified explanation. This drive would cause the spacetime fabric in front of the ship to contract, while causing spacetime behind it to expand.
This can be compared to a surfer being carried along the water; the water doesn’t necessarily move with the surfer, it’s the waves moving up and down that propel them forward. Sadly, while many believe that this could work, we are a long way away from making this a reality. We currently don’t have the technology to manipulate space in such a way, and even if we did, we would likely need large amounts of negative energy to power the device. What’s negative energy? I’m glad you asked. The Heisenberg uncertainty principle states that the energy density of any electric, magnetic, or other field fluctuates randomly. It’s been found that if you suppress these fluctuations in a vacuum, you can increase the positive energies in some places, while causing the regions that previously had 0 energy to possess negative energy.
Essentially, one area of space borrows energy from a region that didn’t have any to start with, producing negative energy. Unfortunately, this has only been done to produce very small amounts of negative energy, which leads many scientists to believe that it will be quite some time before we can make enough to power a warp drive, if it is even possible. And now we return to our question: Could we Travel Faster than the Speed of Light? Well, in terms of physically moving faster than light speed, it seems that it can’t be done. That said, we do have some promising ideas of how to EFFECTIVELY move faster than the speed of light, like the Alcubierre drive, but we still have a lot to learn before this can become a reality. However, with enough technological advances, and with the ability to produce large amounts of negative energy, we could eventually find ourselves travelling to a galaxy far, far away, or even, a long time ago.
Thank you for watching Life’s Biggest Questions, I hope this was interesting and informative, and maybe even inspired you to look into it further on your own. If you liked this video, please thumbs up and subscribe to the channel down below. While you’re down there, let me know if you think we’ll ever figure out a way to move faster than light. Until next time, I’m Ron McKenzie-Lefurgey with Life’s Biggest Questions, wishing you the best of luck, on your quest for answers..