How do we know for sure that nothing is faster than light?
How do we know that nothing can travel faster than the speed of light?
Why do we assume that travelling faster than the speed of light necessitates time travel? Speed of Light: How fast can we move? Why is the speed of light not infinite? Why does light travel so fast? What would happen if we travel at the speed of light? What happen if we moving with the speed of light? Why does everything with time slow down as one travels close to the speed of light? Why does light travel so fast in space? We are travelling at light speed according to photons. But we shouldn't be able to reach the speed of light, so why does this happen? What’s the speed of light? If you could travel the speed of light, what would happen? What is the speed of light? What would happen if I travel with a speed of light? What happens to an object if it reaches the speed of light? What would happen if an object would reach the speed of light? If I could travel at the speed of light, what would I see? Will the speed of light ever change? How does time slow down when you travel near the speed of light? I think this is a very stupid question: in the reference frame of a photon, aren't we moving at the speed of light or faster? Why is time slower near heavy objects? Why is time slower down near heavy objects? If an object could travel at the speed of light, what would happen to it? Special Relativity: What would stop someone accelerating beyond the speed of light if they had achieved 99.9% of the speed of light? How much time passes for someone traveling at light speed for 20,000 light years? Why is the speed of light so small relative to the size of the universe? Why do we age slower when traveling at or near the speed of light in space? If in theory an object reached the speed of light what would happen to it? What would happen if someone ran faster than the speed limit? Can the speed of light be increased? What is the speed of light through different media?