Recent content by sneh

I don't see how it is actually shorter (though I understand it is observed to be shorter) So from here I would say that the photon is obviously moving diagonally through space no matter which perspective -- The observer on the train has matching velocity in one direction to the photon...

I think it's a flawed thought experiment. While moving at a constant velocity, the photon would need to be directed at an angle to reach the other mirror, bounce off at angle, and so on.. This means the photon is traveling the same distance in space, and taking the same amount of time, from...

Would that not evade the whole point the thought experiment is trying to make?

They recently discovered that our galaxy is twice as thick as what was previously thought, which is a pretty big discrepancy. So I would assume we're not actually very close to accurately calculating our true position in the galaxy?

Ah yes, time. Thanks. I should maybe save further arguments for another thread! (I think only space curves relative time, not time itself)

Fair point. When we say curve, is that referring to the maths more than literally curved? (My impression is curved space just means it's basically more "bunched up" in physical terms - so like light taking longer to go through glass, it takes longer to travel through denser "bunched up" space.. ?)

To be effected by gravity, light would have to have mass, which would then prevent it from traveling at the speed of light in the first place?! But then, how does light traveling in a vacuum get "sucked backwards" like swimming against a current?