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Re: Binomial expansion to 4th power - entropy

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On 8/12/2015 2:36 PM, Y wrote:
> On Thursday, August 13, 2015 at 5:12:52 AM UTC+10, Odd Bodkin wrote:
>> On 8/12/2015 1:02 PM, Y wrote:
>>> On Thursday, August 13, 2015 at 3:09:59 AM UTC+10, Odd Bodkin wrote:
>>>> On 8/12/2015 11:19 AM, Y wrote:
>>>>> If a system increases in entropy over time, then we should expect the state of that
>>>>> system to become less predictable over time.
>>>>
>>>> I don't understand why you think this is true.
>>>
>>> I think the reason you don't understand why this is true is because no unambiguous definition
>>> in physics describes heat death of the universe.
>>
>> Really? What's the conflicting definitions you've run into?
>
>
> We're discussing one right now. This is a common conversation.

I'm sorry, I don't see any conflicting definitions of heat death in this 
conversation. What conflicting definitions have you run into?

>
>
>>>> In a heath-death universe, the entropy is maximal and it is VERY
>>>> predictable what happens in that universe -- practically nothing.
>>>
>>> Well your assertion is hotly debatable. For starters, observation requires work or energy transfer
>>> which wouldn't be possible in the scenario of heat death you mention. In the scenario of a universe
>>> having experienced heat death, energy no longer transfers through systems. I can't imagine a system
>>> MORE unpredictable than one that cannot be observed.
>>
>> Well, if you don't have any energy transfers enough to support
>> observation, then you don't have energy transfers enough to do anything
>> else, n'cest pas? Unless you think just about anything can happen in a
>> universe without energy transfers....
>
> That isn't the point. The point is that you cannot make predictions about a system you cannot observe.
> There really is no "maximum" entropy other than the complete inability to make predictions about the
> arrangement of a system.

I can fully predict that nothing will happen in a universe where there 
isn't enough energy transfer available to support observation. I think 
that's a pretty basic physical premise.

Now if you think that once observation is impossible, then it's entirely 
possible for all sorts of wild goings-on to occur in the unobserved 
universe, just say so.

>
>
>>> Entropy regards the arrangement of a system. The more energy transferring through a system, the
>>> greater number of ways a system can be arranged therefore being more unpredictable (greater entropy).
>>
>> Well, this seems at odds with the notion of heat death, doesn't it?
>
> No. In his Treatise on Thermodynamics, Max Planck argued that entropy of the universe has no meaning
> since it admits no accurate definition.

Well, I'm pretty sure most physicists these days would disagree. Entropy 
has a pretty clear definition, originated by Boltzmann, and expanded 
quite a bit in glorious detail since then.

If you're counting on entropy being a term you can fling around 
cavalierly because you read someone's sound bite from something written 
110 years said it was a vague term, then I'm afraid you're going to get 
a little flak for that thought.

>
> If one forces themselves to reconcile the notion of heat death with predictability (invoking entropy),
> then it stands as I previously stated. A universe that is heat dead cannot be observed, and therefore
> remains entirely unpredictable.

See my comment above.

>
>> That's a state with maximal entropy, but with no energy being
>> transferred through the system. So this is in direct conflict with your
>> idea that the MORE energy being transferred through the system is an
>> indication of higher entropy.
>>
>> I see that as a problem, don't you?
>
> Not at all. The universe would "presumably" be left in a state of arrangements where the greatest
> possible number of energy transfers have already taken place. They wouldn't be observable (of course),
> but the greatest number of energy transfers have taken place in a universe that is heat dead.

Energy transfers that have taken place in the past don't tell you much 
about the energy transfers that are going on now. In heat death, the 
number of heat transfers going on now is infinitesimally small, and 
entropy is maximum.




-- 
Odd Bodkin --- maker of fine toys, tools, tables

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Thread

Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 09:19 -0700
  Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 09:22 -0700
  Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 12:09 -0500
    Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 11:02 -0700
      Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 14:12 -0500
        Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 12:36 -0700
          Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 12:42 -0700
            Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 15:36 -0500
            Re: Binomial expansion to 4th power - entropy John Gogo <jfgogo22@yahoo.com> - 2015-08-12 18:33 -0700
          Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 14:51 -0500
            Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 13:03 -0700
              Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 15:37 -0500
                Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 14:42 -0700
                Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 14:44 -0700
                Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 16:45 -0500
                Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 15:52 -0700
                Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-12 18:00 -0500
                Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-12 17:25 -0700
                Re: Binomial expansion to 4th power - entropy Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 07:19 -0500
  Re: Binomial expansion to 4th power - entropy Tom Roberts <tjroberts137@sbcglobal.net> - 2015-08-12 23:21 -0500
    Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-13 06:50 -0700
      Re: Binomial expansion to 4th power - entropy Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 18:59 +0000
        Re: Binomial expansion to 4th power - entropy Tom Roberts <tjroberts137@sbcglobal.net> - 2015-08-14 20:13 -0500
    Re: Binomial expansion to 4th power - entropy Y <yanarchi@hotmail.com> - 2015-08-13 07:22 -0700
      Re: Binomial expansion to 4th power - entropy Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-13 16:50 +0200
      Re: Binomial expansion to 4th power - entropy Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 18:53 +0000
  Binomial expansion to 4th power - entropy fuller.david@hotmail.com - 2015-08-13 06:35 -0700

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