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KurtLudwig

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KurtLudwig

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jbriggs444

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Dodging the question...Summary::Does entropy always increase even in a contracting universe?

In a shrinking universe heat will increase, but also volume available to place particles will decrease. What happens to entropy when the volume gets very small and the temperature is very high?

If you were to find that entropy is decreasing in this situation then you will find that time's arrow runs toward larger volumes and decreasing heat. So entropy still increases over time.

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KurtLudwig

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Thank you

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KurtLudwig

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I have read that our universe started with a very low entropy. Is it known why the entropy was low?

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KurtLudwig

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I have read in "Reality is not what it seems" a book by renowned physicist Carlo Rovelli that time does not exist at the quantum level. In the same book, it is stated that space is granular, that is, quanta of space. "Reality are covariant quantum fields. From the book, these fields do not live in space time, they live, so to speak, one on top of the other: fields on fields. Space and time that we perceive in large scale are our blurred and approximate image of one of these quantum fields: the gravitational field."

Personally, I like classical physics much better. I like calculus and Newton's, Gauss', Faraday's and Maxwell's Laws. All need space and time.

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The established theories of physics, including quantum theory and also relativistic quantum field theory (the standard model of elementary particle physics, describing all known matter and fields except gravity) work with a classical spacetime model (either Galilei-Newton spacetime for non-relativistic or Einstein-Minkowski spacetime for special-relativistic physics; or the description of these known constituents in a given classical general-relativistic spacetime for simple cases of such a spacetime like (anti-)deSitter spacetime).

Also unfortunately Nature doesn't ask which kind of physics we humans like more. She just behaves as she does, but the good thing is that all the math you use in classical physics also applies to quantum physics too!

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zanick

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I assume you know that entropy can decrease locally , as long as it increases over all in any isolated system. i mention this , because you bring up "entropy at the quantum level". what exactly are you asking?Summary::Does entropy always increase even in a contracting universe?

In a shrinking universe heat will increase, but also volume available to place particles will decrease. What happens to entropy when the volume gets very small and the temperature is very high?

- #9

KurtLudwig

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Life itself, due to bio-chemical instructions from DNA, seems to me to be a process that reverses entropy on a local scale. I have read that overall, taking all life support processes into account, entropy (disorder or unknown information about a system) still increases.

I accept the judgement of physicists that overall entropy increases, but there seem to be short term local

exceptions.

Is there a maximum amount of disorder? What drives this increasing disorder?

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