Entropy and the early univesre

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Discussion Overview

The discussion revolves around the concept of entropy in the universe, particularly in relation to the early universe and the Big Bang. Participants explore the relationship between entropy, order, and thermodynamic systems, questioning whether the universe started in a state of order and how entropy behaves over time.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that as entropy in the universe increases, going back in time would imply an increase in order, questioning if there was a point of extreme order at the Big Bang.
  • Others argue that the Big Bang may have started with very low entropy due to energy being concentrated in a small space, suggesting that this state was not necessarily orderly.
  • There is a distinction made between order and entropy, with some participants noting that a system in thermodynamic equilibrium is not more orderly, but rather more probable, which challenges the common association of disorder with high entropy.
  • A participant acknowledges confusion between order and entropy, particularly in the context of black holes.
  • Concerns are raised about popular science misrepresenting the relationship between disorder and entropy, suggesting that definitions are often not clearly communicated.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between entropy and order, with no consensus reached on whether the early universe was orderly or how to interpret the implications of entropy over time.

Contextual Notes

Participants highlight the potential confusion arising from popular science narratives and the need for clearer definitions regarding entropy and order, indicating that misunderstandings may stem from these sources.

bananan
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Hello,
since entropy in the univesre is always increasing, if we were to go back in time, would the amount of order increase? will there get to be a point where the universe is extremely orderly?

Did the big bang start out as a very orderly object?
 
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bananan said:
Hello,
since entropy in the univesre is always increasing, if we were to go back in time, would the amount of order increase? will there get to be a point where the universe is extremely orderly?

Did the big bang start out as a very orderly object?
Entropy is a measure of how dispersed the energy is. In the pre-big bang, the energy was very concentrated in a very small space so it had very low entropy.

Do not confuse order with entropy. Entropy increases because the most probable result of combining two thermodynamic systems is thermodynamic equilibrium. A system in thermodynamic equilibrium is not more orderly than one that is not. It is simply much more probable.

AM
 
Andrew Mason said:
Entropy is a measure of how dispersed the energy is. In the pre-big bang, the energy was very concentrated in a very small space so it had very low entropy.

Do not confuse order with entropy. Entropy increases because the most probable result of combining two thermodynamic systems is thermodynamic equilibrium. A system in thermodynamic equilibrium is not more orderly than one that is not. It is simply much more probable.

AM

ISn't that also true for black holes? I did confuse order with entropy.
 
I blame that on poor popular science, which seems to be hell-bent on associating disorder with entropy, while not highlighting the true definition.
 

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