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marcus

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## Main Question or Discussion Point

Smolin used a really interesting analogy for the big bounce transition here:

http://cosmicvariance.com/2007/07/02/against-bounces/#comment-294116

the idea is a phase transition of the geometry of space which resets it to low entropy---and it looks like Bojowald's recent paper supports the possibility of this without violating the operational form of the Second Law.

The operational Second Law says that entropy is nondecreasing as defined and measured by an observer (who gives meaning to the idea of macrostates of the system, by what he or she is able to measure.)

Roger Penrose loves to point out that low entropy for gravity (i.e. geometry) is INTUITIVELY THE EXACT OPPOSITE of low entropy for matter. The more

But with gas molecules, spread out uniform in the container is HIGH entropy. If the gas starts out clustered and bunched in one corner, that is low entropy and it will immediately start to spread out and get more and more uniformly distributed.

So the universe starts out with very lowentropy gravitational field, totally uniform spread out, because the matter is just uniform cloud or wall-to-wall fire, however you picture it

and the first thing gravity starts doing is CURDLING AND CLUMPING and getting bumpier, as things begin to coagulate. It's how galaxies came to be.

and that is INCREASE OF ENTROPY in the gravitational field or overall geometry.

====================

Smolin didn't specify what metal. I will put the analogy in my own words to make it as graphically definite for myself as I can. In my version, it says Picture the cosmological bounce as going thru a planck regime of extreme temperature and density during which "space melts" and actually the idea of macroscopic space is no longer meaningful.

It would be like say a statue or complicated goldsmith's artwork with all kinds of filegris and figleaves and grillwork and maybe some frogs or a figure of Adam and Eve and the Apple Tree or whatever----somebody paid Giovanni Bellini to produce all this clumping and clustering (like the galaxies of a used universe) and you MELT IT down to an ingot.

In terms of the gravitational field, you have reset the entropy back to "zero". It is a uniform block of metal with lowest possible entropy (thinking gravity)

although of course thinking matter, when you melt something you increase the entropy----but if you look at it that way you dont understand the analogy.

http://cosmicvariance.com/2007/07/02/against-bounces/#comment-294116

the idea is a phase transition of the geometry of space which resets it to low entropy---and it looks like Bojowald's recent paper supports the possibility of this without violating the operational form of the Second Law.

The operational Second Law says that entropy is nondecreasing as defined and measured by an observer (who gives meaning to the idea of macrostates of the system, by what he or she is able to measure.)

Roger Penrose loves to point out that low entropy for gravity (i.e. geometry) is INTUITIVELY THE EXACT OPPOSITE of low entropy for matter. The more

**uniform**spatial geometry is, and the less clumpy/lumpy, the lower entropy.But with gas molecules, spread out uniform in the container is HIGH entropy. If the gas starts out clustered and bunched in one corner, that is low entropy and it will immediately start to spread out and get more and more uniformly distributed.

Code:

```
geometry(gravity) matter
low entropy uniform spread clumped
high entropy clumped uniform spread
```

and the first thing gravity starts doing is CURDLING AND CLUMPING and getting bumpier, as things begin to coagulate. It's how galaxies came to be.

and that is INCREASE OF ENTROPY in the gravitational field or overall geometry.

====================

Smolin didn't specify what metal. I will put the analogy in my own words to make it as graphically definite for myself as I can. In my version, it says Picture the cosmological bounce as going thru a planck regime of extreme temperature and density during which "space melts" and actually the idea of macroscopic space is no longer meaningful.

It would be like say a statue or complicated goldsmith's artwork with all kinds of filegris and figleaves and grillwork and maybe some frogs or a figure of Adam and Eve and the Apple Tree or whatever----somebody paid Giovanni Bellini to produce all this clumping and clustering (like the galaxies of a used universe) and you MELT IT down to an ingot.

In terms of the gravitational field, you have reset the entropy back to "zero". It is a uniform block of metal with lowest possible entropy (thinking gravity)

although of course thinking matter, when you melt something you increase the entropy----but if you look at it that way you dont understand the analogy.

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