4 ms·

Totally agree. Also you wouldn't see any eggs, and you wouldn't be making any conclusions based on seeing any eggs because it would be your neurons un-firing t

Totally agree. Also you wouldn't see any eggs, and you wouldn't be making any conclusions based on seeing any eggs because it would be your neurons un-firing that would cause your eyes to emit photons at the egg. Wouldn't it? Or... what? Is that seeing? If everything goes backwards, isn't that the same as going forwards? The whole question and answer never made any sense to me. Seems like a lot of words to say nothing. Usually I would say that the problem is I don't understand, but more and more I'm seeing that people just don't know, but like to pretend they know. Some people think they find an answer, run with it, becomes a meme, and that's it. "The arrow of time goes forward because we see eggs break". I hope there's at least a couple physicists somewhere that do truly understand it. But the rest, the egg-breakers, I don't know.

rnhmjoj 4y ago
> The whole question and answer never made any sense to me. Seems like a lot of words to say nothing. The breaking egg is meant to explain Loschmidt's paradox: the observation that ordinary processes are not just as likely to happen in the reverse direction than the forward one, unlike microscopic one (say, two colliding particles) even if classical Newtonian dynamics says they should be. The resolution is pretty subtle as it has more to do with the practicality of our definitions that some fundamental truth. While it's true that classical systems have this time-reversal symmetry, as they evolve (more and more collision take place, molecules form and break, etc.) the information that is neatly packed into the initial positions and velocities get more and more spread out into subtle correlations between many different quantities that are hard to measure. If at some point you decide to ignore them you get irreversibility and the law of increasing entropy, which gives you the "arrow of time". So, the laws are symmetrical but in a kind of pointless way for everyday life. Now, what is time and how do we perceive it is a whole different deal and I'm not even trying to answer, but I think that entropy has not much to do with this. > If everything goes backwards, isn't that the same as going forwards? Essentially yes, with some caveats in particle physics. > Some people think they find an answer, run with it, becomes a meme, and that's it. "The arrow of time goes forward because we see eggs break". Well, fundamental questions rarely find an answer that satisfy everyone.

rnhmjoj 4y ago

> The whole question and answer never made any sense to me. Seems like a lot of words to say nothing. The breaking egg is meant to explain Loschmidt's paradox: the observation that ordinary processes are not just as likely to happen in the reverse direction than the forward one, unlike microscopic one (say, two colliding particles) even if classical Newtonian dynamics says they should be. The resolution is pretty subtle as it has more to do with the practicality of our definitions that some fundamental truth. While it's true that classical systems have this time-reversal symmetry, as they evolve (more and more collision take place, molecules form and break, etc.) the information that is neatly packed into the initial positions and velocities get more and more spread out into subtle correlations between many different quantities that are hard to measure. If at some point you decide to ignore them you get irreversibility and the law of increasing entropy, which gives you the "arrow of time". So, the laws are symmetrical but in a kind of pointless way for everyday life. Now, what is time and how do we perceive it is a whole different deal and I'm not even trying to answer, but I think that entropy has not much to do with this. > If everything goes backwards, isn't that the same as going forwards? Essentially yes, with some caveats in particle physics. > Some people think they find an answer, run with it, becomes a meme, and that's it. "The arrow of time goes forward because we see eggs break". Well, fundamental questions rarely find an answer that satisfy everyone.