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Imagine a spaceship powered not by engines, but by compressing the space-time in front of it. This is the realm of science fiction, right? Well, not quite. Physicists have been investigating the theoretical possibility of “warp drives” for decades, and a new study published in Open Journal of Astrophysics takes things one step further – simulating the gravitational waves such a device might emit if it were to malfunction.

Warp drives are staples of science fiction and could, in principle, propel spaceships faster than the speed of light. Unfortunately, there are many problems with constructing them in practice, such as requiring an exotic type of matter with negative energy.

Other problems with the warp drive metric include the potential for it to be used to create closed time-like curves that break causality and, more practically, the difficulty for humans on the ship in actually controlling and deactivating the balloon.

This new research is the result of a collaboration between gravitational physics specialists at Queen Mary University of London, the University of Potsdam, the Max Planck Institute (MPI) for Gravitational Physics Potsdam and Cardiff University. Although he does not claim to have cracked the warp drive code, he does investigate the theoretical implications of warp drive “failure to hold” using numerical simulations.

Dr Katie Clough of Queen Mary University of London, first author of the study, explains: “Although warp drives are purely theoretical, they have a well-defined description in Einstein’s theory of general relativity, and so numerical simulations allow us to investigate the impact they can have on spacetime in the form of gravitational waves.”

Co-author Dr Sebastian Hahn from Cardiff University’s School of Physics and Astronomy added: “Miguel Alcubierre created the first warp drive solution during his PhD at Cardiff University in 1994 and subsequently worked at MPI in Potsdam. it is only natural that we continue the tradition of warp drive research in the era of gravitational wave astronomy.”

The results are fascinating. The collapsing warp drive generates a distinct burst of gravitational waves, ripples in space-time that can be detected by gravitational wave detectors that are usually aimed at merging black holes and neutron stars. Unlike chirps from merging astrophysical objects, this signal would be a short, high-frequency burst, so current detectors would not pick it up.

However, future higher frequency instruments could, and although no such instruments have yet been funded, the technology to build them exists. This raises the possibility of using these signals to look for evidence of warp drive technology, even if we can’t build it ourselves.

Dr Hahn warns: “In our study, the original form of space-time is the warp bubble described by Alcubierre. Although we were able to demonstrate that an observable signal could in principle be detected by future detectors, given the speculative nature of the work, this is not enough to drive instrument development.”

The study also delves into the energy dynamics of the collapsing warp drive. The process emits a wave of negative energetic matter followed by alternating positive and negative waves. This complex dance leads to a net increase in the total energy of the system and could in principle provide another signature of the collapse if the outgoing waves interact with normal matter.

This research pushes the boundaries of our understanding of exotic space-time and gravitational waves. Prof. Dietrich commented: “For me, the most important aspect of the research is the novelty of accurately modeling space-time dynamics with negative energy and the possibility of extending the techniques to physical situations that can help us better understand the evolution and the origin of our universe or the avoidance of singularities at the center of black holes.”

Dr Clough added: “It’s a reminder that theoretical ideas can push us to explore the universe in new ways. While we’re skeptical about the likelihood of seeing anything, I really think it’s interesting enough to be worth a look.”

The researchers plan to study how the signal changes with different models of warp drive and study the collapse of bubbles traveling at speeds exceeding the speed of light itself. Warp speed may be far off, but the quest to understand the secrets of the universe continues, one simulated disaster at a time.