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Comment by rndn | Hacker News Reader

Relative to matter? Photons are massless, so light doesn't get slowed down by interacting with remote particles as it travels.

Relative to humans? Humans are made of matter, and in addition to that, they are immensely complex bio-chemical mechanisms and depend a lot on slow stochastic processes such as diffusion, so a lot of other processes will appear fast to them.

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From reading the article (and not enjoying it very much - see msravi's comment about its handwavyness), the question it's failing to answer isn't "why is light faster than X" but rather "why is the speed of light as it is".

In a lot of ways, that question is just about as meaningful as "why are there electrons?" Looked at from the right angle, you can say that there is only one speed at which everything always moves through space-time; the only difference, really, among speeds is how much of that speed extends timewards from the moving thing's perspective. (What space-time itself gets up to, and what it is apart from something we experience, is a different set of questions altogether.) The idea that we ought to be able to understand everything in principle is a horse long out of the barn.

Its definitely an interesting question. Something that limits all, moves uniformly no matter the point of view, doesn't interact with itself but does with everything else - its a singular feature of physics.

If I understand you right, one can wonder things like, maybe 'light' is really 'time' in some sense, not moving uniformly but instead the actual clock that drives the universe. Stuff like that is, at the least, interesting fodder for bull sessions.

The question you might ask is why doesn't EVERYTHING travel at the speed of light. The speed of light is one in some units. We just happened to develop the meter and the second before we could measure the speed of light. These units are totally arbitrary.

Everything does travel at the speed of light. It's the only speed that exists. When you aren't moving relative to the space around you, you are traveling at the speed of light along the time axis. As your speed increases through space, your speed along the time axis decreases to compensate, ensuring that your total speed in space-time is the speed of light.

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