From: g.scholten@nospam.gmx.de
Ned Latham wrote:
>> > Entropy and gravity work antagonistically (so to speak). The one
>> > works to disperse energy/matter; the other to consolidate it/them.
>>
>> That's wrong.
>
> If yoy examone it with your eyes open, you'll see otherwise.
In fact, it's the other way round: if YOU examine it with your eyes
open, you'll see otherwise (than you described).
> Yout ideal gas in a bottle analogy is neither relevant nor apt.
Indeed, and due to that, your statement that the 2nd Law would tend to
disperse matter (i.e. prefer an equal distribution) which is based on
considering an ideal gas isn't relevant, too.
>> An extreme case would be that all matter of the universe were
>> compressed in black holes. According to Bekensteoin-Hawking entropy
>> of black holes, the total entropy of the universe would then be much
>> higher than in the case of equal distribution of all matter
>> particles.
>
> You're arguing postulate as fact.
Just as you do.
>> So, your statement that star formation could continue forever, since
>> the entropy of the universe could remain constant
>
> I didn't say it would remain constant.
You said, star formation would continue forever. To facilitate that,
entropy at least must not grow over long time periods.
>> because gravity neutralized the grow of entropy,
>
> Nor did I say that gravity "neutralises" entropy.
> I saud that the two are antagonistic.
What can only mean that you want to say that gravity tends to lower
entropy. Or in other ways: tends to neutralize the grow of entropy.
>> is wrong.
>
> My statement that star formation will continue forever *might* turn
> out to be wrong, but it won't be for reasons such as you have given.
Yes, it will be. Your statement is wrong.
>> > We can regard the universe as a closed system, but unlike the
>> > Second Law, we cannot ignore gravity.
>>
>> The Second Law of thermodynamics does NOT ignore gravity. Only some
>> of its applications, like an ideal gas in a bottle, do. Other
>> applications do not.
>
> Feel free to show something you think might pass as evidence of that.
> Be sure to check that you're evidencing the "Law" itself, not some
> "application" of it.
The only way to evidence a law is by evidencing its applications. So,
requiring to evidende a law without evidencing some its applications
does not make sense.
For the 2nd Law, there are e.g. the following three applications:
1) A gas in a bottle, with attractive forces between the gas particles
being weak enough to be neglected. In this application, it turns out
that the 2nd Law tends to disperse that gas particles, i.e. prefers a
state of equal distribution. And in this application, we ignore gravity
(by considering attractive forces as weak enough to be neglected).
2) A gas in a bottle, with attractive, but non-gravitational forces
between the gas particles as so strong that we have to take them into
account. In this application, it turns out that for high temperatures,
the 2nd Law still tends to disperse the particles, whereas for low
temperatures, prefers a liquid state with the particles being close to
each other and not equally distributed. And in this application, we
still ignore gravity (the attractive forces are non-gravitational).
3) A cosmic medium with attractive gravitational forces. In this
application, the 2nd Law does not prefer a state of equal distribution.
i.e. does not tend to disperse matter, but prefers a clumpy distribution
of matter. And in this application, we do not ignore gravity.
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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