Entropy

whiteholes · Post by **whiteholes** » Fri Mar 02, 2007 11:22 am

The second law of thermodynamics does not state that entropy must increase. It states that overall entropy of the whole system increases, but entropy will increase in some places and decrease in others. The second law of thermodynamics is not a certainty but possibilities. There is a greater possibility of entropy increasing then decreasing, therfore overall it increases but in some places it decreases.

For example a box with a pendulum swinging freely without resistance from air or friction. let's say there are 3 particles of gas in box and 11 units of energy in the box. All 11 units of energy comes from the pendulum at the start. If we have 10 units of energy in the pendulum and one in the particles of gas, we have 1 state, being (1,0,0). 1 in the 1st particle 0 in the other 2. if we have 2 units of energy in the particles and 9 in the pendulum, we have 2 possible states. (2,0,0) and (1,1,0). but if we have all 11 units in the particles and none in the pendulum, we will have a total of 16 possible states. The total number of states is calculated to be 83. 1/83 would be 1 unit of energy in particles. 16/83 would be 11 units in particles. THerfore, there is a higher possibility that the final result would be 11 units in the particles and none in the pendulum. BUT it is still possible that the pendulum has more energy at the end. But there is no space with only 3 particles of gas. The more particles the greater the possibility that the particles will have the energy and pendulum none.

jermng · Post by **jermng** » Fri Mar 02, 2007 12:05 pm

Yeah, I dun get the point of your posts ...

Also, pls state your source, if any.

whiteholes · Post by **whiteholes** » Fri Mar 02, 2007 12:11 pm

Those are just my ideas. If you disagree with anything that just explain. Then we will discuss.

jermng · Post by **jermng** » Fri Mar 02, 2007 12:38 pm

The second law of thermodynamics is not a certainty but possibilities.

I don't know about entropy, but the above statement seems contradictory in itself.

Isn't a Law supposed to be -

a. a statement of a relation or sequence of phenomena invariable under the same conditions.

or more importantly -

b. a principle based on the predictable consequences of a condition

thus, I don't see how a law is "not a certainty but possibilities." Then having that in the opening almost negates everything after that ... or maybe I'm not going deep enough ..

*source - Random House Unabridged dictionary

whiteholes · Post by **whiteholes** » Fri Mar 02, 2007 1:57 pm

The second law of thermodynamics is not a certainty but possibilities.

There is this steorotype that entropy can ONLY increase but it is possible for entropy to decrease as illustrated above. Although there is a possibility of it decreasing, the chances of it doing so in our world is very very little.

a principle based on the predictable consequences of a condition

The probability of it decreasing is so slight that it never happens. That's why the results can always be predicted.

Does this clear any doubts? :|

jermng · Post by **jermng** » Fri Mar 02, 2007 2:23 pm

Still doesn;t answer the question whether it's a Law or an uncertainty.

The probability of it decreasing is so slight that it never happens. That's why the results can always be predicted.

vs.

Although there is a possibility of it increasing, the chances of it doing so in our world is very very little.

seems even more contradictory now ... Are you sure you're using "increasing" and "decreasing" in the right places?

Cos from what I gather here, the possibility of it increasing AND decreasing are both very slight ..

In that case, I still don't see the point of discussion here ...

whiteholes · Post by **whiteholes** » Fri Mar 02, 2007 4:35 pm

lol.

Although there is a possibility of it increasing, the chances of it doing so in our world is very very little.

change that to decreasing.

Still doesn;t answer the question whether it's a Law or an uncertainty.

Why doesnt it not answer? It is a law only because you don't observe decreasing entropy. BUT it can decrease. quantum physics

understand.

wucheeyiun · Post by **wucheeyiun** » Fri Mar 02, 2007 5:44 pm

http://answers.yahoo.com/question/index ... 628AALnRgh

jermng · Post by **jermng** » Fri Mar 02, 2007 6:05 pm

understand.

no.

whiteholes · Post by **whiteholes** » Fri Mar 02, 2007 10:10 pm

jermng wrote:
understand.
no.

forget it.