Ask HN: What is the most complex topic you understand?

Entropy.

It was hard for me to understand this arbitrary rule of things becoming less ordered over time. Was this just a fundamental natural law?

The answer is no. Entropy is a logical consequence of probability and time.

Why do things become more chaotic over time? Because chaotic configurations have a higher probability of occurring.

There are far more disordered configurations of things then there are ordered, this is why things become more disorder with time. Time changes the configuration. And by probability a high probability configuration is more likely to occur then a low probability configuration. So the axiom of nature here is not entropy, it's probability. Entropy is just a consequence of probability.

There are systems where ordered configurations are more numerous then disordered configuration and in those systems things become more ordered with time. In these cases entropy is STILL defined to be increasing as things get more ordered. Thus entropy is not describing disorder, or is it?

The thing I don't fully understand yet is heat entropy. Apparently when you take heat into account for everything, the disordered intuition suddenly becomes applicable. So if you have a system becoming more ordered with time, heat must be increasing somewhere to offset this increase in order. Maybe someone can explain this part to me?

I came here to say this. Once I get something, it becomes too obvious.

I'm not sure there's anything that I understand, at least not fully. There are things I know a certain amount about, but probably nothing that I understand as fully as I'd like.

Also, understanding can be fleeting if you don't think about a certain topic all the time. Take relativity for example: I recall a very specific moment when I was talking to a friend who is actually formally educated in Physics, and we were talking about the speed of light, time dilation, mass expansion, etc. And I had a definite "aha" moment when I understood why mass has to increase with velocity and why time dilation had to occur. But... could I explain it to somebody else now (that was probably 10 years ago), and convey the same understanding? Do I even understand it as well now as I did in that moment? Arguably not. :-(

OTOH, if you just ask "What's a topic that you know a lot about?" I'd say, generally speaking, "firefighting" and "computer programming, especially in Java". shrug

I agree with the sentiment if the "another level deeper" is still the same topic. But, eg., I can be an expert in performant software programming without understanding hardware in depth. Understanding roughly how hardware (eg. word alignment) affects software performance is enough - no need to understand how signals propagate in a conductor.

That seems like unlocking the next level of hacking one's own consciousnes. I understand why this is interesting.