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Jingy
climber
Somewhere out there
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calculating when and were the Moon will rise... from any point on the Earth's surface
 Thank you, Ed... Now I want to find out for myself too..
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madbolter1
Big Wall climber
Denver, CO
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what's "the entire universe" there are parts of the "entire universe" which are no longer in thermal contact with other parts... so as a "universal" idea, entropy has to be limited to the causally connected parts, which means that the universe is not necessarily in equilibrium as a whole...
Could you explain how you know this?
Whatever "evidence" you have for these "disconnected" parts of the universe implies a causal connection. Even if you say that there "was" a causal connection that we are "only now" detecting, but that connection is now gone, implies evidence of the "goneness," which I'd like to understand.
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madbolter1
Big Wall climber
Denver, CO
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That makes zero sense.
If you can see it it obviously had a casual effect on you. Or the telescope detector. Or whatever.
Thank you
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JEleazarian
Trad climber
Fresno CA
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Beautiful shot, Ed.
As for entropy, Dan Smith, Art Brook and I were trying to determine a business name in 1969 or 1970. We loved General Dynamics, but since it was already taken, we decided on General Entropy. We even manufactured some smashies under a subsidiary of General Entropy, named Acme Smashies.
Sad to say, our venture as industrialists was not particularly remunerative, but we always thought it would be a good idea to be asociated with something that was increasing. We even had a firm motto: "The Second Law of Thermodynamics is for your protection."
Now you're telling me that the entropy of the universe isn't necessarily increasing? How could you?
John
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Gnome Ofthe Diabase
climber
Out Of Bed
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May 25, 2017 - 06:34am PT
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Thnx Doc! Wow what a picture !
That stuff about the Two theories that attempt to solve the horizon problem -
1) the theory of cosmic inflation and 2) variable speed of light.
as so often is true , seems to be beyond my grasp.
Be sure I will go and check it out as I believe Learning never stops.
V V V V
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Ed Hartouni
Trad climber
Livermore, CA
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May 25, 2017 - 07:17pm PT
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the image from the broken link above:
the problem with causal connection in the universe as it applies to the uniformity (or non-uniformity) is referred to as the "horizon problem" which you can get an idea about here:
http://en.wikipedia.org/wiki/Horizon_problem
for those of you interested in a slightly more elaborate explanation, see S. Weinberg Cosmology pg. 205-206
"...Therefore in a matter- or radiation-dominated universe no physical influence could have smoothed out the initial inhomogeneities and brought points at a redshift z_L that are separated by more than a few degrees to the same temperature, in contradiction with the nearly perfect isotropy of the microwave background at large angular scales observed ever since the microwave background radiation was discovered."
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