Faster-than-light (FTL) travel is a staple of sci-fi, hand-waving away multi-millennia journeys between stars. Such a technology would of course be incredibly handy to us in the real world, and while these “warp drives” have been considered theoretically possible, they usually involve exotic physics that are out of our reach. Now, astrophysicist Erik Lentz has outlined a new theoretical design that could allow FTL travel based on conventional physics.
If humanity is going to stand the test of time, we need to expand beyond Earth. But where can we go? Elon Musk might have his heart set on Mars, but conditions there are hardly ideal. In fact, nowhere else in our solar system really works for us. So we should turn our attention to other stars.
While there are almost certainly other Earth-like planets out there somewhere, the universe is just too damn big for us to reach them in any practical time frame. Using current chemical rockets, it would take more than 50,000 years to reach Alpha Centauri, our nearest neighbor.
And that’s where the FTL dream comes in. If we could travel at the speed of light, the journey drops to a little over four years, meaning a return trip could easily fit into a normal human lifespan. Some hypothetical warp drive designs could get there in as little as five months – shorter than our current journey time to Mars.
The problem is, according to Einstein’s general theory of relativity, it’s physically impossible for anything to travel faster than the speed of light. That’s because as an object moves faster, its mass increases, so by the time you reach the speed of light that mass would approach infinity. Plus, it would require infinite energy to accelerate to that speed.