The new warp drive concept warps space, and doesn’t move us very quickly

A team of physicists has discovered that it is possible to build a real, actual warp engine without breaking any known rules of physics. One caveat: a warp-action ship can’t exceed the speed of light, so it won’t be getting anywhere interesting anytime soon. But this research still represents an important advance in our understanding of gravity.

Moving without moving

Einstein’s general theory of relativity is a toolkit for solving problems related to gravity that relates mass and energy to distortions in spacetime. In turn, these space-time distortions tell mass and energy how to move. In almost all cases, physicists use the equations of relativity to figure out how a given group of objects moves. They have some physics scenarios, such as a planet orbiting a star or two black holes colliding, and they wonder how these objects distort space-time and what the subsequent evolution of the system is.

But it is also possible to run Einstein’s calculations in reverse by imagining some desired motion and asking what kind of distortion of space-time would make it possible. This is how Mexican physicist Miguel Alcubierre discovered the physical basis of the warp drive, a long-standing staple of physics. Star Trek Commercial franchise.

The goal of a warp drive is to get from A to B in between commercial breaks, which usually involves faster-than-light movement. But special relativity explicitly prohibits faster-than-light speeds. While this did not bother the book Star TrekIt made Alcubierre angry. He discovered that it was possible to construct a warp drive through clever manipulation of space-time, arranging it so that the space in front of the ship was erased and the space behind the ship was extended. This generates movement without movement in the strict sense of the word.

It may seem like a contradiction, but it is just one of the many fascinating aspects of general relativity. The Alcubierre warp drive avoids violations of the speed of light limit because it never moves during space; Instead, space itself is, in essence, manipulated to bring the spacecraft closer to its destination.

Although puzzling, Alcubierre’s design had a fatal flaw. To provide the necessary space-time distortions, the spacecraft must contain some form of exotic matter, which is typically negative-mass matter. Negative mass faces some conceptual problems that seem to challenge our understanding of physics, such as the possibility that if you kicked a ball weighing negative 5 kilograms, it would fly backwards, violating the principle of conservation of momentum. Additionally, no one has ever seen a negative mass object exist in the real universe at all.

These problems with negative mass have led physicists to propose various versions of “energy conditions” as adjuncts to general relativity. These are not built into relativity itself, but additions are needed because general relativity allows for things like negative mass that don’t seem to exist in our universe, and these energy conditions keep them out of relativity’s equations. It’s scientists’ response to the troubling fact that vanilla GR allows for things like super-light movement, but the rest of the universe doesn’t seem to agree.

Warp factor is zero

The energy conditions have not been proven experimentally or observationally, but they are data that are consistent with all observations of the universe, so most physicists take them seriously. Until recently, physicists viewed these energy conditions as making it 100% clear that you couldn’t build a warp drive, even if you really wanted to.

But there is a way around that, discovered by an international team of physicists led by Jared Fox at the University of Alabama in Huntsville. (The team is also affiliated with the Applied Physics Propulsion Laboratory, a virtual research center dedicated to researching, among many other things, warp drives.) In a paper that has been accepted for publication in the journal Classical and quantum gravityresearchers delved into relativity to explore whether any version of torsion drive could work.

The equations of general relativity are very difficult to solve, especially in complex cases like a warp drive. So the team turned to software algorithms; Instead of trying to solve the equations manually, they explored their solutions numerically and verified their compliance with the energy conditions.

The team didn’t actually try to build a propulsion device. Instead, they explored different solutions to general relativity that would allow travel from one point to another without the ship experiencing any acceleration or experiencing any crushing tidal forces within the ship, providing great relief to any imaginative passengers. They then checked whether these solutions adhered to the energy conditions that prevented the use of foreign matter.

Researchers have already discovered a solution to warp drive: a way to manipulate space so that travelers can move without acceleration. However, there’s no such thing as a free lunch, and the nature of this warp drive comes with a major caveat: the ship and passengers cannot travel faster than light. Also disappointing: the fact that the researchers behind the new work don’t seem to care about knowing what configurations of matter allow distortion to occur.