Nearly 60 years ago, the original Star Trek series ignited a dream in the public\u2019s imagination: that one day, people would travel the galaxy in ships propelled by faster-than-light \u201cwarp drives.\u201d<\/p>\n
The idea that future humans could hop in a vessel and arrive at a distant star system that afternoon soon became a staple of science fiction, not just in Star Trek but in dozens of other movies, TV shows, and books beloved by generations of fans.<\/p>\n
Many of those fans were children who would grow up to become scientists. And today, some of those scientists are bending spacetime itself to bring warp drive closer to reality.<\/p>\n
(The farthest journey in human history is about to begin<\/a>.)<\/p>\n For decades, most physicists considered warp drive to be impossible. But in the past few years, theoretical research has suggested that the fictional technology does not necessarily violate any laws of physics\u2014a discovery that has ignited a wave of interest in creating real warp drive technology.<\/p>\n And while there are still many practical challenges to work out\u2014in particular, how to generate and harness the immense energy needed\u2014some physicists say it\u2019s not outside the realm of possibility.<\/p>\n \u201cIt\u2019s amazing how science fiction writers imagine things, and we then figure out they can work,\u201d says Alexey Bobrick, an astrophysicist and pioneering warp drive researcher at Applied Physics<\/a>, a public benefit company that works with governments and the private sector. \u201cIt\u2019s really quite beautiful.\u201d<\/p>\n From sci-fi to theoretical physics<\/p>\n There\u2019s a reason physicists like Bobrick are taking warp drive seriously: The concept isn\u2019t actually that far-fetched. Compared with other sci-fi ideas for moving faster-than-light, like wormholes and extradimensional hyperdrives, warp drive is \u201cthe easiest to make compatible with known physics,\u201d says physicist and science communicator Sabine Hossenfelder<\/a>, who regularly shares new<\/a> warp drive<\/a> research<\/a> on her popular YouTube channel.<\/p>\n In science fiction, a warp drive is a propulsion system that creates a bubble of spacetime around a spaceship. That bubble is then accelerated to move faster than the speed of light. Taken at face value, this may sound impossible: After all, according to Einstein\u2019s theory of relativity, objects in our universe cannot be accelerated<\/a> beyond the lightspeed barrier.<\/p>\n But spacetime itself can bend or warp at any speed.<\/p>\n Star Trek science advisor and astrophysicist Erin MacDonald says it\u2019s useful to think of spacetime as a fabric within which objects\u2014from stars to spaceships\u2014are embedded. \u201cIf you wrap your ship in the fabric of spacetime and then that fabric goes faster than light, carrying you with it, that’s actually not breaking any laws of physics,\u201d says MacDonald.<\/p>\n (Hibernating humans? The race to unlock a sci-fi superpower<\/a>.)<\/p>\n This concept had existed<\/a> in science fiction literature before Star Trek made its debut.It\u2019s not surprising thatStar Trekcreator Gene Roddenberrychose to adopt warp drive versus a more fantastical flavor of faster-than-light travel, according to author and Star Trek historian Ryan Britt<\/a>. Roddenberry \u201cwas obsessed with fact-checking as much as he could,\u201d Britt says. \u201cThat wasn\u2019t something that existed in science fiction television ever before.\u201d<\/p>\n But as plausible asthe general concept may have been, warp drive was still seen as purely fictional. The problem, MacDonald explains, is that distorting spacetime in this manner would take a mind-boggling amount of energy.<\/p>\n In a seminal 1994 paper<\/a> on warp drive\u2014considered the first serious scientific look at how it might work\u2014physicist Miguel Alcubierre devised a mathematical model that would contract spacetime in front of a ship and expand it behind the ship. While the so-called Alcubierre drive could move a bubble of spacetime at any speed, he found that generating a bubble even as small as a few meters in diameter would require an amount of energy comparable to the mass of the sun.<\/p>\n Furthermore, Alcubierre\u2019s calculations required the existence of an exotic form of \u201cnegative energy\u201d to make the drive compatible with Einstein\u2019s theory of relativity. Unfortunately, negative energy appears to be a purely mathematical concept and \u201cnot something that seems to exist\u201d in our universe, Hossenfelder says.<\/p>\n From theoretical to physical warp drives<\/p>\n In the years following Alcubierre\u2019s paper, other researchers, including those at NASA<\/a>, tinkered with his model. Many follow-up papers attempted to reduce the negative energy requirements.<\/p>\n Bobrick first learned about warp drive while studying general relativity in college. He found it intriguing. \u201cIt sat in the back of my mind for a long, long time,\u201d he says.<\/p>\n When Bobrick met Applied Physics co-founder Gianni Martire and learned of his interest in the topic, the pair decided to investigate warp drive more closely.<\/p>\n (Could Jurassic Park really happen? We asked scientists about sci-fi movies<\/a>.)<\/p>\n Instead of tinkering with the Alcubierre drive, the pair decided to start from scratch and see if they could construct a new, more physical, model. They started simple, restricting their analysis to warp drives moving at constant speeds. (Alcubierre\u2019s drive could accelerate or decelerate, which is more mathematically complicated to describe.)<\/p>\n In 2021, Bobrick and Martire published a paper<\/a> in the journal Classical and Quantum Gravity titled \u201cIntroducing Physical Warp Drives.\u201d In it, they describe the general geometry of a warp bubble with an inner passenger area where spacetime is flat, surrounded by a curved, outer wall that exerts a gravitational field. This stood in contrast to Alcubierre\u2019s warp bubble, which does not gravitationally tug on objects outside of it\u2014part of what Bobrick says makes it unphysical.<\/p>\n Their model does not require negative energy\u2014however it would still take several Jupiter-sized objects\u2019 worth of energy to move a bubble several meters across, Bobrick says, \u201cwhich is prohibitively too much.\u201d<\/p>\n Yet the bigger caveat of Bobrick and Martire\u2019s warp bubble is that it can only move slower than the speed of light. This may come as a disappointment to Star Trek fans, but physicists say it\u2019s still an important step toward moving warp technology out of the realm of science fiction.<\/p>\n \u201cNow we have a much better mathematical basis to study warp drives,\u201d Hossenfelder said<\/a> in a video published when the paper first came out. \u201cWe know what the warped spacetime looks like.\u201d<\/p>\n Engage! Making warp drive a reality<\/p>\n Now that scientists have a more realistic model of a warp bubble, the key question becomes finding a way to change its speed. After all, in a hypothetical future where warp drive is used for space travel, bubbles will need to speed up, slow down, and come to a stop to let passengers on and off a ship. \u201cDescribing that whole process is quite crucial,\u201d Bobrick says.<\/p>\n More theoretical work is also needed to reduce warp drive\u2019s energy needs. Even with a hypothetical, futuristic energy source like cold fusion<\/a> on hand, producing several planets\u2019 worth of energy is likely unfeasible.<\/p>\n (Cosmic radiation gave the Fantastic Four superpowers. Here’s what would happen in real life<\/a>.)<\/p>\n While there\u2019s a lot left to do to prove warp drive is even theoretically achievable, Bobrick says that the field of warp drive has seen \u201cquite a lot of fresh thinking\u201d over the past few years. Indeed, his 2021 paper has been cited over 60 times<\/a>, including by warp drive researchers in Canada, Argentina, Europe, and New Zealand. (It has even attracted some critics<\/a>\u2014a sign at very least that he\u2019s not alone in taking the subject seriously.)<\/p>\n