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Comment by nico | Hacker News Reader

Isn’t perpetual motion the basis of the whole universe?

I mean, it hasn’t stopped yet, right? And it technically does all the work we do?

Perpetual motion actually means a violation of the first or second law of thermodynamics, rather than just something moving for a very long time.

That's perpetual motion machines, not perpetual motion. As a closed system, the universe (as a whole, not in parts) absolutely qualifies as being in perpetual motion, you just can't take energy out of the system.

(which is convenient for us, because we're part of the system)

Okay sure, it’s just that no one uses the term “perpetual motion” except to refer to perpetual motion machines as I described. Even the Wikipedia article on the topic is titled “perpetual motion.” And the entire universe, as far as we know, is not in perpetual motion. i.e. does not violate the laws of thermodynamics.

I don't think you can apply the laws of thermodynamics to the Big Bang.

First there was nothing, then there was everything. For currently undefined values of "first" and "then."

It's very much an out-of-scope problem.

No (serious) person uses it for the quantum scale either. Same problem, just other end of the scale. The very idea of "motion" doesn't even apply to quantum particles.

what if some higher beings outside of our universe is using us (this universe) as a perpetual machine!

Then it's no longer perpetual, because the total energy in the system decreases over time.

That’s a Rick and Morty episode

Doesn't the heat death of the universe contradict this?

That's only one plausible ending to the universe, while perhaps favored, certainly far from being determined.

Then there's handwaving about given a large enough time scale energy should randomly concentrate enough to 'restart' the universe or something silly along those lines.

For myself I like the notion of the universe starting from a breaking of symmetry of whatever base form of energy the universe is built out of.

This allows for scattering of information, increasing diversity and complexity of the system, while also not adding or creating any new energy.

So if the universe can start in a place of equilibrium I'd imagine after heat death leads to a static state then 'restarting' is possible since it's happened at least once.

Hasn't been empirically observed yet ;-P

Seriously thou: it seems reasonable to assume that our current models of the universe may be incomplete.

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