A new theoretical paper, published in the journal Classical and Quantum Gravity, reignites the debate about the possibility of superluminal (faster-than-light) travel based on conventional physics.
“If travel to distant stars within an individual’s lifetime is going to be possible, means of faster-than-light propulsion will have to be found,” said Dr. Erik Lentz, a researcher at the Institut für Astrophysik at the Georg-August Universitat Göttingen.
“To date, even recent research about superluminal transport based on Einstein’s theory of general relativity would require vast amounts of hypothetical particles and states of matter that have exotic physical properties such as negative energy density.”
“This type of matter either cannot currently be found or cannot be manufactured in viable quantities.”
“In contrast, the new research gets around this problem by constructing a new class of hyper-fast solitons — or ‘warp bubbles,’ compact waves that maintain their shape and move at constant velocity — using sources with only positive energies that can enable travel at any speed.”
According to Dr. Lentz’s paper, there are yet-to-be explored configurations of space-time curvature organized into ‘solitons’ that have the potential to solve the puzzle while being physically viable.
“We derived the Einstein equations for unexplored soliton configurations (where the space-time metric’s shift vector components obey a hyperbolic relation), finding that the altered space-time geometries could be formed in a way that worked even with conventional energy sources,” he said.
“In essence, the new method uses the very structure of space and time arranged in a soliton to provide a solution to faster-than-light travel, which — unlike other research — would only need sources with positive energy densities. No ‘exotic’ negative energy densities needed.”
“In addition, the solitons were configured to contain a region with minimal tidal forces such that the passing of time inside the soliton matches the time outside: an ideal environment for a spacecraft.”
This means there would not be the complications of the so-called ‘twin paradox’ whereby one twin traveling near the speed of light would age much more slowly than the other twin who stayed on Earth: in fact, according to the recent equations both twins would be the same age when reunited.
“This work has moved the problem of faster-than-light travel one step away from theoretical research in fundamental physics and closer to engineering,” Dr. Lentz said.
“The next step is to figure out how to bring down the astronomical amount of energy needed to within the range of today’s technologies, such as a large modern nuclear fission power plant. Then we can talk about building the first prototypes.”
“The energy required for this drive traveling at light speed encompassing a spacecraft of 100 m (328 feet) in radius is on the order of hundreds of times of the mass of Jupiter.”
“The energy savings would need to be drastic, of approximately 30 orders of magnitude to be in range of modern nuclear fission reactors.”
“Fortunately, several energy-saving mechanisms have been proposed in earlier research that can potentially lower the energy required by nearly 60 orders of magnitude.”