Everyone thinks it would be cool to travel at the speed of light, which is why scientists devote their lives to working out if it would be possible and NASA is trying to develop its own warp drive. But easy, tiger: turns out super-fast space travel would be fatal.
A paper published in Natural Science brings some boring common sense to the speed-of-light-travel table. In order to travel huge distances in next to no time, people need to travel close to the speed of light. In so doing, travellers cover extremely large distances very quickly, and thanks to the quirks of relativity, it would feel like it took mere minutes because of an effect known as time dilation, which squashes perceived time.
The trouble is that travelling close to the speed of light brings about other effects too. In Natural Science, Edelstein and Edelstein point out that hydrogen in any craft cable of travelling at the speed of light would also prevent it from travelling at the speed of light. They explain:
Unfortunately, as spaceship velocities approach the speed of light, interstellar hydrogen H, although only present at a density of approximately 1.8 atoms/cm3, turns into intense radiation that would quickly kill passengers and destroy electronic instrumentation. In addition, the energy loss of ionizing radiation passing through the ship’s hull represents an increasing heat load that necessitates large expenditures of energy to cool the ship.
In other words, travel close to the speed of light and you’ll be bombarded with so much radiation that you kick the bucket. The knock-on effect is that even if it’s possible to create a craft capable of travelling close the speed of light, it wouldn’t be able to transport people.
Instead, there’s a natural speed limit imposed by safe levels of radiation due to hydrogen, which means humans couldn’t travel faster than half the speed of light unless they were willing to die almost immediately. Dammit. [Natural Science]
Image: Reha Mark/Shutterstock