Question entropy rises over time right?

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Discussion Overview

The discussion centers around the concept of entropy in the universe, specifically addressing whether entropy rises over time and how this relates to the organization of matter in different states, such as hot plasma versus the modern universe with its galaxies and planets. The scope includes theoretical considerations of entropy in both expanding and static or collapsing universes.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants assert that the entropy of the universe rises over time, while local entropy can decrease if it results in a greater increase in the surrounding entropy.
  • One participant questions the use of the term "organized" when comparing a ball of hot plasma to the modern universe, suggesting that it may lead to misunderstandings about entropy.
  • A participant explains that the SI unit of entropy (J/K) relates to the ratio of mass-energy to temperature, noting that as the universe's temperature decreases, its entropy increases.
  • Another participant raises a hypothetical scenario about a static or collapsing universe, questioning whether entropy would remain the same or decrease in such conditions.

Areas of Agreement / Disagreement

Participants generally agree that entropy rises over time in the universe, but there are competing views regarding the implications of this rise and the conditions under which entropy may behave differently, such as in a static or collapsing universe. The discussion remains unresolved regarding the effects of these hypothetical scenarios on entropy.

Contextual Notes

There are limitations in the assumptions made about the nature of entropy in different cosmic conditions, and the discussion does not resolve the implications of a static or collapsing universe on entropy levels.

skywolf
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i have a question
entropy rises over time right?
how is a ball of hot plasma more organized than the modern universe with its galaxies, planets, and people?
 
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The entropy of the universe rises over time. Local entropy can fall as long as it increases the entropy around it.
 
skywolf said:
i have a question
entropy rises over time right?

In a finite expanding universe, entropy increases.

how is a ball of hot plasma more organized than the modern universe with its galaxies, planets, and people?

Forget the word "organized" here. It will only mislead.

First, the SI unit of Entropy is J/K. That means Joules per Kelvin (not "just kidding" :-p)

That means in simple terms the ratio of mass-energy to temperature.

Consider the universe's changing entropy:

The far-away Cosmic Background Radiation used to be 3000 degrees Kelvin. Now it is a little under 3 degrees Kelvin. The mass hasn't decreased by a factor by 1000, whereas the temperature has. That's why the universe is increasing in entropy.

J/K is increasing.
 
Last edited:
what if the universe was static(somehow) or even collapsing?
then would the entropy stay the same?
or even lower?
 

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