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| questioner1 |
 Posted: Mon Mar 01, 2010 1:21 pm Post subject: Can we reverse the second law of thermodynamics? |
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Forum Freshman
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First of all, I'm actually kind of surprised that the second law of thermodynamics made it into a law. the law is based on chance, basically. in a closed system, entropy always TENDS to go up, but there are fluctuations, and sometimes, entropy will go down, just by pure chance (http://www.ted.com/talks/sean_carroll_on_the_arrow_of_time.html).
Now since this law is not absolute, isn't it possible, that because we are intelligent, we can create the conditions so, that entropy will decrease?
Maybe i dont understand the concept of entropy fully. entropy i learned is dissorder, but i presume this only means that energy in the form of heat is equally distributed within the system if the entropy is high, and unequally distributed if low, right?
So this would have nothing to do with the structure of matter, but with the heat energy that matter has?
So can we turn the tide against the second law? |
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| inow |
| Posted: Mon Mar 01, 2010 1:26 pm Post subject: |
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| questioner1 |
| Posted: Mon Mar 01, 2010 1:30 pm Post subject: |
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i already watched his presentation. what he said was that entropy always increases, but with fluctuations. so sometimes the entropy actually decreases, but it just increases alot more often.
you know the example of the glass with cream on the top and coffee on the bottom?
if you wait, the cream and coffee will mix together, but they will never go back apart.
but if you actually wait long enough, (longer than the age of the universe) it will actually turn back apart, that's what he said.
He also said that the second law is not absolute. im not making this up. |
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| Harold14370 |
| Posted: Mon Mar 01, 2010 2:36 pm Post subject: |
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Moderator
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| questioner1 wrote: |
| He also said that the second law is not absolute. im not making this up. |
It's a bit like saying the laws of probability are not absolute, so you can win at roulette in Las Vegas. Well, sometimes you can win a little but in the long run, you lose. |
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| DrRocket |
| Posted: Mon Mar 01, 2010 10:19 pm Post subject: Re: Can we reverse the second law of thermodynamics? |
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Forum Radioactive Isotope
Joined: 12 Aug 2008
Posts: 3114
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| questioner1 wrote: |
First of all, I'm actually kind of surprised that the second law of thermodynamics made it into a law. the law is based on chance, basically. in a closed system, entropy always TENDS to go up, but there are fluctuations, and sometimes, entropy will go down, just by pure chance (http://www.ted.com/talks/sean_carroll_on_the_arrow_of_time.html).
Now since this law is not absolute, isn't it possible, that because we are intelligent, we can create the conditions so, that entropy will decrease?
Maybe i dont understand the concept of entropy fully. entropy i learned is dissorder, but i presume this only means that energy in the form of heat is equally distributed within the system if the entropy is high, and unequally distributed if low, right?
So this would have nothing to do with the structure of matter, but with the heat energy that matter has?
So can we turn the tide against the second law? |
It is quite true that thermodynamcis in general and the second law in particular are statistical in nature. So they are not absolute laws.
On the other hand, they are valid statistical laws, and the law of large numbers is a valid theorem in the theory of probability.
So, no you cannot reverse the second law of thermodynamics. |
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| Water Nosfim |
| Posted: Mon Mar 01, 2010 10:40 pm Post subject: yes you can |
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| questioner1 |
| Posted: Mon Mar 01, 2010 11:58 pm Post subject: |
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Joined: 01 Mar 2010
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"It's a bit like saying the laws of probability are not absolute, so you can win at roulette in Las Vegas. Well, sometimes you can win a little but in the long run, you lose."
Well you could grab the ball and throw it where you want to. i know that's cheating, but why is this similar thing not possible in thermodynamics?
"It is quite true that thermodynamcis in general and the second law in particular are statistical in nature. So they are not absolute laws.
On the other hand, they are valid statistical laws, and the law of large numbers is a valid theorem in the theory of probability.
So, no you cannot reverse the second law of thermodynamics."
I know the statistical laws are valid, but do they always apply?
I think you misunderstood my question.
I'm not trying to disprove the second law, i just want to understand why you can't reverse it. |
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| Ophiolite |
| Posted: Tue Mar 02, 2010 4:58 am Post subject: |
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Time Lord
Joined: 25 Jul 2005
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| questioner1 wrote: |
| Well you could grab the ball and throw it where you want to. i know that's cheating, but why is this similar thing not possible in thermodynamics?. |
Isn't that Maxwell's demon?
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The Universe is not only weirder than we imagine it is weirder than we can imagine. J.B.S.Haldane. |
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| DrRocket |
| Posted: Tue Mar 02, 2010 5:52 am Post subject: |
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Forum Radioactive Isotope
Joined: 12 Aug 2008
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| questioner1 wrote: |
"
I know the statistical laws are valid, but do they always apply?
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Yes |
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| DrRocket |
| Posted: Tue Mar 02, 2010 5:53 am Post subject: |
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Forum Radioactive Isotope
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| Ophiolite wrote: |
| questioner1 wrote: |
| Well you could grab the ball and throw it where you want to. i know that's cheating, but why is this similar thing not possible in thermodynamics?. |
Isn't that Maxwell's demon? |
Precisely |
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| Renata Braukamper |
| Posted: Thu Mar 04, 2010 9:09 pm Post subject: |
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New Member
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| questioner1 |
| Posted: Thu Mar 04, 2010 11:19 pm Post subject: |
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Joined: 01 Mar 2010
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I don't understand why maxwell's demon doesn't work.
i know that his intervening in the system makes him part of the system, and that his 'intelligence' required to let all the warm molecules to the warm part of the system, increases entropy itself.
but i do not understand why his intelligence necessarily requires increasing entrop, and how we can theoretically say that this increase HAS to be higher than the entropy he decreases in the rest of the system. |
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| Water Nosfim |
| Posted: Fri Mar 05, 2010 12:50 am Post subject: boiler |
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Forum Freshman
Joined: 01 Aug 2009
Posts: 47
Location: Israel
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| wat about hot water boiler ? the hot get on top . thanks |
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| questioner1 |
| Posted: Fri Mar 05, 2010 1:12 am Post subject: |
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Forum Freshman
Joined: 01 Mar 2010
Posts: 32
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yeah. i don't understand that either.
and what about this: you have a one sided mirror (the ones they use in interrogation, so that the police can see the criminal but not vice versa)
You put two substances on both sides of the mirror, won't one side eventually get colder than the other, because more light energy is emitted from one to the other? |
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| Pong |
| Posted: Fri Mar 05, 2010 1:30 am Post subject: |
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Forum Radioactive Isotope
Joined: 08 Apr 2008
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| questioner1 wrote: |
| Well you could grab the ball and throw it where you want to. |
LOL You rock. You live. Well put.
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A pong by any other name is still a pong. -williampinn |
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