Like why planet? Why sphere? Why is there a solar system? Why system instead of no system? How did entropy create anti-entropy agents? Bees, humans, anything that builds non-random structures?
Sorry if this is a bad question, it just popped into my head and it won’t go away.
In: Other
[Here](https://www.youtube.com/watch?v=uD4izuDMUQA) is a really interesting video on the (possible) ultimate fate of the universe.
Imagine you want to make brownies. You start with a clean, orderly kitchen and neat bowls of ingredients. As you mix things, your kitchen gets messier, and so does your oven and the brownie pan. And then when you eat the brownies you make even more mess.
When you’re done, you have more mess than when you started: but you also got brownies for a while.
The universe is kind of like that. Big, low-entropy mixes of matter and energy are slowly making the universe into a high-entropy place. But along the way, we temporarily get cool stuff like stars and planets. The local entropy is reduced temporarily, but the *total* entropy still increased.
At the end, it’ll all be high-entropy: but we also got planets and stars and life and stuff for a while.
Simple answer: energy in.
In an energy neutral environment, things tend toward entropy, but you’d be hard pressed to find an environment that isn’t getting fresh injections of energy.
The Earth gets sunlight, for example.
I think it’s a cycle really.. A chaotic system, at some point, will become ordered and an ordered system will, at some point, become chaotic. It’s the ebb and flow of reality
Sorry to get all philosophical
Stars are really big. Flying around Earth in a commercial jet takes about 45 hours. If you tried that on the Sun, you’d be flying for 19 years.
All that energy causes systems to form. People, bees, snowflakes, everything. The energy to make it comes from the sun. If you were to add it all up, *the sun loses more energy than the planets gain*. But Earth gains energy, and that’s where most order comes from.
Entropy DOES NOT EQUAL Complexity
This is a question I had too – how do we see order in the world around us if entropy is supposed to be increasing? But what is important to understand is the difference between order and complexity.
If we look at a human, what does it do – fundamentally, we try survive. But surviving involves turning food into energy and using that energy to generate heat, to move, to cause disorder. These all involve complex processes, that may seem ordered, but are actually creating disorder.
Similarly, the sun compresses hydrogen to form helium and releases vast amounts of energy, increasing entropy. There may be several types of coordinated fusion happening but it is all complexity, not entropy.
So why does it happen at all? It is a positive feedback loop. Provide energy to a system and it can do complex things to generate more energy – give a human food and they will think of ways to build tools that help them cause more disorder – it is just a way of speeding up the conversion of order to disorder.
Source – A great minute physics video – have a google of it, it’s a better explainer than me
The Universe gets more messy with time — but part of it can get in order, as long as another part gets *even more* disordered.
Rack up a set of pool balls (and block the pockets), and break them with the cue. Call the energy you used to hit the cue, **X**. The question: can you return the balls back to the rack?
Of course you can. Can you come up with a way to do it that, even if you do it a whole bunch of times, uses *less* energy than **X**?
The ELI5 answer is “no”. That’s why cars break down, but people have to fix them. Rooms get messy, and people need to clean them. You have to mess up the *whole universe* more, to tidy up your corner a little less.
In truest ELI5 fashion “Because we haven’t had enough time to get rid of everything.”.
In slightly more sensible reasoning, because on its way towards eventually having nothing in it, there’s nothing that prevents localized order from arising because on a large enough viewpoint order decayed further.
One way to put it is a freezer. Inside you can lose/halt/etc entropy by dropping the temperature and freezing everything. However this was achieved by basically moving that entropy somewhere else, the heat that radiates out the back of your freezer. Furthermore, because a system can never be perfectly 100% efficient (or ‘worse’ a system can never be MORE than 100% efficient) the act of locally reducing entropy actually increases entropy overall. Terrible example: Your freezer might make a given volume cooler by 1 degree, but when it does that it makes a similar volume hotter by 1.1 degrees.
In reality it’s a lot more complex then that, but overall the universe and it’s gradual march towards entropy doesn’t really care that any given location might be reversing its effects because the overall entropy level is always increasing and the act of reversing entropy in one location ALWAYS increases entropy in another, and effectively always increases the total entropy more than if nothing had happened at all.
MC Hawking taught me that Entropy only thrives in closed systems, but Earth, the solar system, and the universe are open systems, so that’s why everything hasn’t decayed away. 😀
The big bang said fuck you to physics and created a very low-entropy universe with shitloads of energy, which we don’t know where it got it from. The entropy of the universe has been steadily increasing since then, but stars have so much energy that they can continually decrease the local entropy of orbiting planets by giving them energy for billions of years.
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