I Why does entropy grow when a solar system is formed?

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Entropy increases during solar system formation due to the interplay of gravitational forces and energy distribution. While a protostellar cloud has lower entropy than the resulting solar system, the process of gravitational collapse leads to heating and radiation, which contributes to a net increase in entropy. As the gas shrinks, it radiates energy into space, spreading it over a larger volume, which outweighs the entropy decrease from matter clumping. The analogy of milk in coffee highlights that the initial energy confinement in the cloud is transformed as it evolves. Understanding this energy distribution is crucial to grasping why entropy grows in this context.
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In "From eternity to here", Sean Carroll writes that the protostellar cloud had a lower entropy than te solar system it produced. That strikes me as odd. A solar system looks more arranged than a dust cloud. What am I missing here?
On page 50 of "From eternity to here", Sean Carroll writes that the protostellar cloud had a lower entropy than the solar system it produced. That strikes me as odd. A solar system looks more arranged than a dust cloud. When talking about entropy, someone always mentions the milk in the coffee. Milk in a drop of milk has lower entropy then milk spread in one of the billion ways it can spread between the "coffee molecules". Wouldn't you aggree, that the milk in a drop looks more like a planet and the milk all spread out looks more like the dustcloud. What am I missing here?
 
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A collapsing cloud of gas is not quite like milk in coffee. The crucial part is that there is an attractive force in the form of gravity.
On the one hand, it causes the cloud to shrink and clump up - which gives us a pause, as this reduces the entropy. But on the other hand, the gas heats up as it shrinks. And then radiates into space. And then shrinks some more. And then radiates. And so on. The key is not to forget about the radiation part.
If we want to think about this in terms of how ordered a system is, it's best to consider where the energy was when you had a cloud, and where it is when it's become a bunch of rocks. You should be able to see that a lot of the energy that was initially confined to the area of space where the cloud was, has been 'smeared' around a huge volume of space (as radiation). This wins over the decrease of entropy from matter clumping into dense balls.

John Baez has a nice write-up on the topic here: https://math.ucr.edu/home/baez/entropy.html , with more detailed treatment. He's a bit coy in not wanting to provide the final answer on a plate, though.
 
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Bandersnatch said:
A collapsing cloud of gas is not quite like milk in coffee. The crucial part is that there is an attractive force in the form of gravity.
On the one hand, it causes the cloud to shrink and clump up - which gives us a pause, as this reduces the entropy. But on the other hand, the gas heats up as it shrinks. And then radiates into space. And then shrinks some more. And then radiates. And so on. The key is not to forget about the radiation part.
If we want to think about this in terms of how ordered a system is, it's best to consider where the energy was when you had a cloud, and where it is when it's become a bunch of rocks. You should be able to see that a lot of the energy that was initially confined to the area of space where the cloud was, has been 'smeared' around a huge volume of space (as radiation). This wins over the decrease of entropy from matter clumping into dense balls.

John Baez has a nice write-up on the topic here: https://math.ucr.edu/home/baez/entropy.html , with more detailed treatment. He's a bit coy in not wanting to provide the final answer on a plate, though.
Thanks, that makes so much sense. The energy part, that was what I was missing.
 
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Oh, poo. I've just noticed. The link attribution should read John Baez. Not his arguably more musical cousin Joan.

[Typo fixed in your post above by a Mentor] :smile:
 
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I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
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