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In boiling soapy water, globs of soap coalesce as the temperature increases to boiling. Does this mean that temperature increases the gravitational pull of bodies?

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Short answer: Nooooo... – Waffle's Crazy Peanut Apr 27 '13 at 11:59
A bit longer answer: it is irrelevant to the gravitational pull. – tia Apr 27 '13 at 12:09
If you're asking whether the bubbles are coalescing because of gravity, then absolutely not--gravity is far too weak to matter here. If you're asking whether heat in general can have direct gravitational effects (i.e., over and above indirect ones like convection redistributing matter), then yes, heat flux contributes to stress-energy tensor and thus gravity. But again that's ludicrously small in any situation you can cook up in a lab. – Stan Liou Apr 27 '13 at 13:22

1 Answer 1

Your question has nothing related to the gravitational force. Gravity (as far as we know) is very very weak. When at some higher temperature, the bubbles simply follow a randomness (brought out as a thermodynamical law called entropy). I mean, the bubbles just randomly go around everywhere and there's a higher probability for many to pop when heated. There's also this probability for some bubbles to merge together (which may appear as they coalesce) and pop. Anyways, the result is popping..!

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I am not a scientist but I have general interest in astro physics. I know that Newtons laws do not always explain what we see in the interaction of galaxies causing the the creation of dark energy and matter to be added to the equations. Even Einsteins generally relativity theories has been adjusted with Lambda (the meaning of which is beyond me). I also note that the essence of gravity has not fully been analyzed. What I was looking for was an explanation for what I observed not a lecture on my ignorance. – Robert Schultz Apr 27 '13 at 12:44
Hi @RobertSchultz: If noticed in the simple expression on Newton's math result, one can clearly see that there's nothing related to temperature in the expression ;-) – Waffle's Crazy Peanut Apr 27 '13 at 12:54
@RobertSchultz: there are a large number of questions on this site relating to dark matter and dark energy, and additionally, there are good wikipedia pages and a variety of googlable blog posts. All of these phenomena only become apparent when looking at objects of the length scale of a galaxy or larger. – Jerry Schirmer Apr 27 '13 at 14:59

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