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   sci.physics.research      Current physics research. (Moderated)      17,520 messages   

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   Message 15,641 of 17,520   
   Phillip Helbig (undress to reply to Gerry Quinn   
   Re: entropy and gravitation   
   02 Jun 17 11:07:20   
   
   XPost: sci.astro.research   
   From: helbig@asclothestro.multivax.de   
      
   In article ,   
   Gerry Quinn  writes:   
      
   > > > To put it another way, the 'clumpy' states in the non-gravitational   
   > > > universe have lower entropy than the smooth state, but the clumpy states   
   > > > in the gravitational universe have higher entropy than the smooth state.   
   > >   
   > > Imagine a clumpy universe with no gravity.  It has low entropy (lower   
   > > than the smooth universe).  Now G starts increasing from zero to, say,   
   > > its current value (at which point the clumpy universe has a higher   
   > > entropy than the smooth universe).  At some value of G, the clumpy   
   > > universe must have the same entropy as the smooth universe (which you   
   > > say has the same entropy with or without gravity).  So for this value of   
   > > G, the entropy is independent of the clumpiness.   
   > >   
   > > Someone has made an error somewhere.   
   >   
   > Why should it not be independent of the clumpiness?   
      
   Because it's not.  A room full of air with the same density everywhere   
   has higher entropy than a room with all of the air squeezed into one   
   corner.  (In the case where gravity can be neglected.  When gravity   
   plays a role, then the clumpier distribution has higher entropy.)   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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