Exploring the Final Frontier - Is Star Trek's Warp Drive Possible?

An artist's depiction of what a real trip at warp speed might look like.

Space: the final frontier... For 60 years the Star Trek franchise has brought its viewers along for spectacular trips across the galaxy and back. Generations of physicists, astronomers, astronauts, and more were inspired to explore their universe thanks to the voyages of the Starship Enterprise. But that continuing mission to explore strange new worlds, seek out new life and new civilizations, and to boldly go where no one has gone before was only possible thanks to warp drive, a form of faster-than-light travel. While Star Trek is science fiction, how accurate was its science? Could we, some day in the future, explore the cosmos with a real-life warp drive? It might just be possible.

Einstein's Speed Limit

According to Einstein’s Theory of Relativity, it is impossible to travel faster than light. The speed of light, 299,792,458 meters per second, is the absolute speed limit of the universe. That means that exploring space beyond our Solar System would take an extremely long time. Moving at the speed of light, it would take over four years to reach even the closest star. A trip to the opposite end of the galaxy would take nearly 80,000 years. If we want to explore space like they do in science fiction, we need to somehow move faster than the speed of light.

While an object cannot move faster through space than the speed of light, there is a potential loophole. Space itself can be altered to allow an object to arrive at a destination faster than light would be able to without warped space. This concept is the fundamental backbone of most faster-than-light engines across science fiction. Having grown up watching Star Trek, the physicist Miguel Alcubierre wanted to figure out a way to make the warp drive a reality, and eventually came up with the idea of the Alcubierre warp drive.

Science Like Fiction

When Gene Roddenberry first created Star Trek, he had no idea how the warp drive actually would function. But, as luck would have it, when actually analyzed scientifically, a remarkably similar faster-than-light drive is hypothetically possible. Alcubierre’s idea was to bend space ahead of and behind a traveling starship. We know the fabric of space can be bent and warped. It’s why we experience gravity.

A diagram visualizing how space would warp around a starship's warp bubble.

By creating a wave distortion in the fabric of space, such that space in front of a ship is contracted while the space behind it is stretched, a starship within this wave, known as a warp bubble, could ride the wave in the fabric of space, almost like a surfer. The ship itself wouldn’t actually be moving in its local bubble of space, but rather it’s the local bubble of space that’s moving. Nothing in the Theory of Relativity prohibits space itself from moving faster than light; it’s only that objects can’t move through space at such speeds. This idea is a fundamental fact of inflation in the early universe, following the Big Bang. So, while the starship will effectively travel faster than light by arriving at a destination sooner than a beam of light could, it never actually breaks the relativistic speed limit.

Reality Check

However, don’t start signing up for Starfleet yet. While the Alcubierre drive is allowed by the Theory of Relativity, that doesn’t actually mean it’s physically possible. Perhaps a warp bubble could exist naturally, but we don’t have the slightest idea how we might generate one. And even if we did, we’d still have no idea how to exit it upon reaching our destination.

Additionally, in order to warp space in the way required to form a warp bubble, you’d need something with negative mass or energy density. We call this hypothetical form of matter exotic matter, which is not to be confused with antimatter, which has opposite charges, or dark matter, which is a type of unknown matter we can’t see. Exotic matter is needed to stretch the space around the warp bubble. Regular matter can only pull space inwards, but exotic matter would have negative gravitational effects and push space outwards. Like a bowling ball on a trampoline, regular matter would create a valley in the fabric of space and trap the starship, but exotic matter would lift it up to create a wave’s crest that can be traversed.

Without exotic matter, the Alcubierre drive would be impossible. Like the drive itself, exotic matter is something that could hypothetically exist without breaking any known laws of physics, but we have no actual evidence of its existence.

What Does the Future Hold?

But don’t rule the warp drive out yet. We have often found that when the math allows for something to exist, it often does. The best example is black holes. Black holes were actually predicted to exist based purely on the math from the Theory of Relativity, but were thought to be so absurdly strange that they couldn’t possibly exist in nature. Given the fact that we had seen no evidence of them, even Einstein said they certainly don’t exist. Despite that, we now know black holes to not only exist, but to be relatively common throughout the universe. It only took the time for our knowledge and technology to grow to the level where we could better understand them. Perhaps the same is true of exotic matter, and therefore the Alcubierre drive.

Perhaps Star Trek’s science fiction isn’t so absurd after all. Maybe, before long, we’ll be taking on voyages across the galaxy aboard faster-than-light starships of our own. The physics certainly allow for it, and that makes for truly exciting possibilities in our future. A future where we will all live long and prosper, just like in Star Trek.