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Comment by nxc18 | Hacker News Reader

I don’t have any physics background so maybe this doesn’t make sense but I’m betting someone can answer.

If time is relative, what is a microsecond when there is nothing to relate it to? What does time dilation do to a microsecond when you’re at the center of a space with the mass of the entire universe?

I’m struggling to interpret a microsecond (or any other unit of time) near the boundary at which time came into existence.

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"time is relative" has a very particular meaning, it's not just a "proverb". It means (in the simpler special relativity) that how fast time seemingly progresses is relative to the difference in velocities of two different inertial frames ("things that move at the same velocity and without external forces").

The only thing that special relativity assumes about flow of time in general is that within each of these frames, the speed of light is the same. This also means that you will always observe time progressing in any inertial frame, unless your relative velocity to it is the speed of light.

Physics is so broken that they cant even explain galaxy rotation (dark matter is a failure) but the media is reporting with authority what was happening microseconds after the “big bang”.

Hard pass.

I expect you're uninformed but I don't know enough to prove it. Either way, I'm annoyed that you've been downvoted without a single reply. I'd like to know if/why you're actually wrong.

It's true that physics can't explain galaxy rotation (speaking as someone who recently taught elementary cosmology at a good university). I don't know whether that has much to do with the big bang though. I expect the downvotes are for non sequitur.

This is just how science works: we find evidence for some things, and we don't have evidence for others, so the things we can explain is limited to what we can back up. For example, we don't know why people yawn but that doesn't mean that we can't explain in detail how sedatives work.

But we also can’t explain in detail how sedatives work... We have no idea whatsoever how most classes of sleeping meds function.

We have a fairly good idea how most sedatives work and which receptors they bind to. But even when we don't, I am not sure what your point is: even when we know some things there are still things we can't explain yet…which was basically what I said?

You are essentially correct - popular scientism outlets do not have an appropriate degree of humility when reporting on things like this. However, the physicists themselves tend to have a good understanding of the caveats and context of their predictions, even if this doesn’t generally end up getting communicated to consumers.

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