The Second Law of Thermodynamics

Originally posted by dj2becker
What makes you think that life is simple? If it is so simple why can't you make it in the lab?

Simple is a relative word and you know it. The sun is simpler than the galaxy. Do you dispute this? If not then why cant you make it in the lab?

Originally posted by adam warlock
when did i say that now the second law applies to open systems? when i said that you had to deal with open systems from the start to the end i meant your reasoning. and dS=dQ/T has nothing to do with the second law of thermodynamics. the second law is dS>0 when the system is isolated.
if you don't believe in me go check the landau and lifschitz book. or any other book on thermodynamics

To introduce the idea of entropy the relation of Qc/Qh=Tc/Th is recalled, which applies to a Carnot engine. This equation can be rearranged as Qc/Tc=Qh/Th, which focuses attention on the heat Q divided by the Kelvin temperature, T. The quantity Q/T is called the change in entropy dS.

dS = dQ/T

This is what the 2nd law is all about.

Originally posted by twhitehead
Simple is a relative word and you know it. The sun is simpler than the galaxy. Do you dispute this? If not then why cant you make it in the lab?

I never made the claim that the sun is simple. Scotty claimed that life was simple and it was no big deal for life to come about by random unintelligent processes. So my question is if it was so simple, why can't he create life even with the intelligence that he has, assuming of course that he has intelligence which I'm sure he won't dispute.

Originally posted by UmbrageOfSnow
My response was deleted because I almost swore and the robomod killed it despite the ****s I used. Sorry.

I was about to post this and some other stuff. We've been being non-rigorous, you are right, in our use of system definitions. Should have been saying isolated sometims.

Anyway
DJ: I'm glad to see you finally at least resorting to thermod ...[text shortened]... 2nd law applies equally to open systems is wrong because of the definition of entropy.

You for one should know that the total entropy of the universe does not change when a reversible process occurs, but increases when an irreversible process occurs.

The second law applies to all systems.

Originally posted by twhitehead
That is far from certain. Can you define complexity? By my understanding of the word, the dead one will usually be more complex. It also contradicts your claims that everything becomes more disorderly as disorder is more complex than order.

Complexity is directly related to functionality. Do you mean to say a dead plant is more functional than a living plant?

Originally posted by dj2becker
You for one should know that the total entropy of the universe does not change when a reversible process occurs, but increases when an irreversible process occurs.

This is not true. There is always an energy change during a chemical reaction, thus entropy must increase.

Back to high school for you, me thinks.

Originally posted by dj2becker
Complexity is directly related to functionality. Do you mean to say a dead plant is more functional than a living plant?

Complexity does not equal functionality. We explained this already with reference to a rusting car.


Go away, and read a book.

Originally posted by dj2becker
Scotty claimed that life was simple

No I didn't.

Stop misquoting me.

Originally posted by dj2becker
I never made the claim that the sun is simple. Scotty claimed that life was simple and it was no big deal for life to come about by random unintelligent processes. So my question is if it was so simple, why can't he create life even with the intelligence that he has, assuming of course that he has intelligence which I'm sure he won't dispute.

You still haven't learnt to read properly. It is me that is saying the sun is simple relative to the galaxy. I even asked if you dispute this and you have not answered. So either dispute it or show us your lab-made sun.

Originally posted by dj2becker
To introduce the idea of entropy the relation of Qc/Qh=Tc/Th is recalled, which applies to a Carnot engine. This equation can be rearranged as Qc/Tc=Qh/Th, which focuses attention on the heat Q divided by the Kelvin temperature, T. The quantity Q/T is called the change in entropy dS.

dS = dQ/T

This is what the 2nd law is all about.

Sod off with the copy and paste jobs.

Originally posted by dj2becker
Complexity is directly related to functionality. Do you mean to say a dead plant is more functional than a living plant?

I didn't ask you what it was related to, I asked you to define it as your understanding of the word is clearly different from mine so we are talking at cross purposes all the time.

Originally posted by scottishinnz
This is not true. There is always an energy change during a chemical reaction, thus entropy must increase.

Back to high school for you, me thinks.

I am afraid you are the one that needs to go back to school...

The total change in entropy for any Carnot engine is thus:

dSc + dSh = Qc/Tc - Qh/Th = 0

The fact that the total change in entropy in a Carnot engine is a specific illustration of a general result. It can be proved that when any reversible process occurs, the change in entropy of the universe is zero;
dSuniverse =0J/K for a reversible process.

The word 'universe' means that dSuniverse takes into account all parts of the system and all parts of the environment. Reversible processes do not alter the total entropy of the universe. To be sure, the one part of the universe may change because of a reversible process, but if so, the entropy if another part changes in the opposite way by the same amount.

Originally posted by scottishinnz
Complexity does not equal functionality. We explained this already with reference to a rusting car.


Go away, and read a book.

That is where I don't agree with your definition of complexity. Would you say that a cell phone with less functions is more complex than a cell phone with more functions?

Originally posted by dj2becker
Would you say that a cell phone with less functions is more complex than a cell phone with more functions?

I'm not sure that "functionality" equates with "lots of functions".

Originally posted by scottishinnz
No I didn't.

Stop misquoting me.

You said: "The earliest life would have been incredibly simple..."