Naked Science Forum
General Science => General Science => Topic started by: layman on 31/12/2011 11:33:43
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I was recently watching a science series and they did the usual teacup falling and breaking thing as an example of entropy. For some reason I thought a little harder about it and came up with a different approach. This universe started with a big bang, it was a super heated chaotic mass, as it cooled the stars formed, stars went nova creating heavier elements and dust clouds for new stars and planets, stars and their planets formed into galaxies, the universe continued to cool and expand. Along the way a scientist dreams up the teacup example but, he is wrong. Even though the teacup was created into an ordered object, it is in reality not. For the universe is trying to involve into an ordered state, a state at rest. The process of creating the teacup is interfering with the universe becoming ordered. A couple of years back I also saw a show about Bose Condensation, which they described the effect of a laser light slowing as it passed through the condensation and resuming as if nothing happened once it was through. Does this mean that time slows as it approaches absolute zero? If this is true when the universe expands, until matter and energy breakdown to the basic particle and the universes temperature reaches absolute zero, does time stop?
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until matter and energy breakdown to the basic particle and the universes temperature reaches absolute zero, does time stop?
In a sense it does. Time can only be "observed" by activity - some sort of change. If everything were to stop moving there really wouldn't be any time.
Whether or not all motion would, or could, cease is beyond me.
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First, the speed of light is NOT constant. It varies according to the medium through which it travels. The maximum speed of light seems to be its speed through a vacuum. However, pass it through a prism and its speed slows a bit according to wave length. Hence the spectrum. Bose Einstein condensate is not a vacuum. It is simply an extreme form of 'medium'.
As for entropy I am a bit baffled myself. However, it seems to be an isolated phenomena of thermodynamics in a closed system. Specifically, 'It determines that thermal energy always flows spontaneously from regions of higher temperature to regions of lower temperature, in the form of heat.' http://en.wikipedia.org/wiki/Entropy
This clearly is not what happens when gravity collapses a cloud of hydrogen into a star. Gravity compresses the cloud increasing its temperature until the ultimate exothermic reaction takes place: nuclear fusion.
If space continues to expand at an ever increasing state, then it could eventually become more powerful then gravity and the whole thing moves towards absolute zero. I suppose this could even overcome the strong nuclear force. If so, the universe might conceivably be reduced to no matter at all.
For instance, if spacial expansion can overcome the strong nuclear force, then it seems logical the resultant quarks could also be 'evaporated' into to electromagnetic radiation.
I have seen no speculation on whether spacial expansion could also evaporate photons.
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First, the speed of light is NOT constant. It varies according to the medium through which it travels. The maximum speed of light seems to be its speed through a vacuum. However, pass it through a prism and its speed slows a bit according to wave length. Hence the spectrum. Bose Einstein condensate is not a vacuum. It is simply an extreme form of 'medium'.
As for entropy I am a bit baffled myself. However, it seems to be an isolated phenomena of thermodynamics in a closed system. Specifically, 'It determines that thermal energy always flows spontaneously from regions of higher temperature to regions of lower temperature, in the form of heat.' http://en.wikipedia.org/wiki/Entropy
This clearly is not what happens when gravity collapses a cloud of hydrogen into a star. Gravity compresses the cloud increasing its temperature until the ultimate exothermic reaction takes place: nuclear fusion.
If space continues to expand at an ever increasing state, then it could eventually become more powerful then gravity and the whole thing moves towards absolute zero. I suppose this could even overcome the strong nuclear force. If so, the universe might conceivably be reduced to no matter at all.
For instance, if spacial expansion can overcome the strong nuclear force, then it seems logical the resultant quarks could also be 'evaporated' into to electromagnetic radiation.
I have seen no speculation on whether spacial expansion could also evaporate photons.
Just to make things clear - the speed of light is constant, it is just that when it goes through a medium (ie other than the vacuum) it does other things on the way (ie interaction with the substance); between those interactions it travels at the same speed as it does in a vacuum.
I don't think the "dark energy" driven accelerated expansion can ever overcome the electromagnetic or the nuclear force - predictions even have the local cluster staying gravitationally bound. The boring heat death predicted is due to the fact that all things decay eventually into energy (ie not that they are ripped apart), which in turn gets red-shifted by the background expansion.
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From what I gathered from the documentary laser light passed through the condensate without losing energy along the way, I may have misinterpreted the information. I may not understand the process but when a material can slow the speed of light down to 60 kliks, in a 12-15 cm cloud of disassociated sodium atom bits and emerge on the other side as if nothing happened, no heat loss, I have to wonder if something else is going on.
*Physicist Lene Hau, experiments*
As for entropy, once again I find myself having confused the facts. To me what I took from the teacup breaking, was ordered systems(teacup) always decay(falling and breaking) into chaos. Nothing about thermodynamics even entered my mind since I've never really given thermodynamics much thought. In my mind everybody else thought the universe is ordered including me because we see all these systems having a sort of chaotic order. My re-evaluation of it, all these systems are a by product of the properties of energy, matter and some potter making teacups. Stars grow old evolving into something else, blackholes evaporate, metals eventually become brittle, molecules breakdown. For me the teacup breaking was not an example of chaos but an example of order overcoming chaos. The universe began in chaos and will eventually become an ordered state through expansion.
I once read a scifi novel, "The Eternity Factor," that described the earlier universe as being more condense. Existing properties then cannot be replicated now because the universe has decreased energies because of the expansion. Or bigger cooler, not as much bang for the buck. Since someone brought it up - will the strong, weak, nuclear or any force remain the same in a universe of decreasing energy. Or in a universe so expanded it can no longer affect anything else around it.
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bump