If we shoot a burst of light from our most powerful laser into space…how far could it travel before fading, it it doesn’t hit anything? And would it travel straight?
In: Physics
Light can’t fade. The reason light appears dimmer at a distance (stars for example) is that fewer photons are reaching you because they’re spreading out spherically from the point of origin.
A photon emitted continues on forever unless it hit’s something and is absorbed. It would travel straight relative to the spacetime it’s in. Since spacetime curvature varies, it might appear to follow a curved path to you, but that’s actually just a straight path in curved space.
If a photon travels past a large mass, the distortion of spacetime by that mass would change the photon’s trajectory, but that’s still the straightest line possible in that curved spacetime.
Latest Answers