Entropy and How can something come from nothing? And some evolution......

Frumious Bandersnatch: I am beginning to wonder if you even know what a Carnot cycle is

Click to expand...

DNAunion: Hmm, isn't that what a heat engine undergoes, where it obtains energy from a heat reservoir, performs work, expels heat to a cold reservoir, and returns to its original starting position, ready for the next iteration, with the efficiency being determined by the difference in temperature between the hot and cold reservoirs?

Frumious Bandersnatch: Here are some pages illustrating the use of the Carnot cycle to explain entropy.

Click to expand...

DNAunion: Thanks but no thanks. I already have college physics books that tell me all I need to know about it. You got any?

DNAunion: Ah, Frumious Bandersnatch is leavin. It's just as well, I don't even know where he and I saw things differently. For example:

1) We both stated that evolution does not defy the second law because organisms are open systems.

2) We both agree that the total entropy of a closed system (as defined in the trichotomous classification) does not have to increase or remain constant: the total entropy of such a system can decrease.

3) We both agree that the "Best" classification scheme is the trichotomous one.

4) We both agree that an isolated system cannot exchange either mass or energy with its surroundings.

5) We both agree that a closed system can exchange energy, but not matter, with its surroundings.

6) We both agree that an open system can exchange energy and matter with its surroundings.

7) We both agree that the surroundings are not part of the system under consideration.

The only disagreement seems to be that Frumious Bandersnatch mistakenly believes that I used "(isolated)" as a regular adjective, as in "an isolated closed system...", which I did not. I used it as a means of providing clarification - elimination of ambiguity - while repeating the statement the original poster made.

I wasn't planning to post anymore on this subject but since you asked me direct questions I thought to give it one more shot.

DNAunion: Thanks but no thanks. I already have college physics books that tell me all I need to know about it. You got any?

Click to expand...

Of course. I have Halliday and Resnick. Doesn't everybody?

Frumious Bandersnatch: Of course it isn't. Who said it was?


DNAunion: Uhm, the author of the physical science text I quoted from. Don't you pay attention?

Click to expand...

You're right.  I was still thinking of the definition you quoted from Solomon et. al where a closed system is clearly defined as isolated.  This illustrates why I really dislike the usage that implicitly refers to a closed system as isolated. Merkin is wrong unless he previously specifically stated that by his definition any closed system exchanges neither mass nor energy. BTW I looked through six of my texts on different subjects (physical chemistry, biophysics, thermodynamics and statistical mechanics) that define thermodynamic systems. All but one, a biochemistry text, use what you call the trichotomous nomenclature and that one is at least clear that the closed systems referred to exchange neither mass nor energy.

3) We both agree that the "Best" classification scheme is the trichotomous one.

Click to expand...

I am glad we agree. I wasn't quite sure from your first posts on the subject.

5) We both agree that a closed system can exchange energy, but not matter, with its surroundings.

Click to expand...

Yes we agree when using the standard definition you gave in post 49 and the superior "trichotomous" classification scheme. I think we also agree that when you refer to a closed(isolated) system you mean a system that exchanges neither mass or energy.

The only disagreement seems to be that Frumious Bandersnatch mistakenly believes that I used "(isolated)" as a regular adjective, as in "an isolated closed system...", which I did not. I used it as a means of providing clarification - elimination of ambiguity - while repeating the statement the original poster made.

Click to expand...

Actually, all I said was that you may have added to the confusion by first using closed(isolated) as in post 38 and then giving a definition of closed that is not isolated in post 49. I understood exactly what you meant when you wrote closed(isolated) and I said that you and Badfish were correct. I further said I thought it might be confusing to others when you later presented (3 times in the same post) a definition of a closed system that was not isolated. It seemed to me that you first eliminated ambiguity and then brought it back again. I think it would have been OK if you had specified at that time that you were discussing different systems of nomenclature(as you did later), especially since you followed that up with three posts 51,52,53 quoting authors that were referring to closed systems that were considered isolated. 

Maybe I was wrong about you possibly adding to the confusion but it seems to me that you were a bit hypersensitive to this relatively minor criticism. You actually blew up at my post #42 without even seeming to realize that I was completely agreeing with you in that one. In fact, I probably was wrong about confusion. For one thing I doubt that anyone else is paying the least bit of attention to this semantic argument so how could anyone have been confused? I did say in a later post that I think adiabatic closed system is a better terminology than closed(isolated) but I will admit that I was being really, really picky because I was feeling a bit frumious at that time for some reason and closed(isolated) as you wrote actually does say the same thing.

The Frumious Bandersnatch

does the universe have an edge?

Today at 02:25 AM webboffin said this in Post #85

does the universe have an edge?

Click to expand...

I would have thought that you might consider the point reached by the microwave background radiation as the edge of the universe.


http://www.damtp.cam.ac.uk/user/gr/public/cmbr_home.html

If that is the case the universe has an edge that is expanding at the speed of light in every direction.

However, this site

http://csep1.phy.ornl.gov/guidry/violence/cosmology.html

says

One of the hardest concepts to accept is that the Universe is everything that is. Not only the matter and energy but all the dimensions as well. There is no `outside' to the Universe and it has no `edge', at least not in the usual sense that we think of these concepts.

When we think of the Big Bang we instinctively think of the small Universe expanding like a sphere into an empty void. Unfortunately this is incorrect. The dimensions that we commonly use, three spatial and one time, are all mixed up when the early Universe is concerned and our normal concepts of space and time are not valid. The only way that it can be partly understood is to consider the two-dimensional analogue of the surface of a balloon which is being inflated. The surface is everywhere continuous, has no edge and yet is expanding. The three-dimensional analogue (whose understanding defeats the writer!) will represent the Universe.

Click to expand...

and this one

http://www.anzwers.org/free/universe/bigbang.html

There no centre of the universe because there is no edge of the universe. In a finite universe, space is curved so that if you could travel billions of light years in a straight line you would eventually finish back where you started. It is also possible that our universe is infinite. In both examples, groups of galaxies completely fill the universe and are moving apart at all points making the universe expand (see question 2).

There no centre of the universe because there is no edge of the universe. In a finite universe, space is curved so that if you could travel billions of light years in a straight line you would eventually finish back where you started. It is also possible that our universe is infinite. In both examples, groups of galaxies completely fill the universe and are moving apart at all points making the universe expand (see question 2).

Click to expand...

So I guess it doesn't have an edge in the usual sense.  If it does have an edge it's pretty hard to get a hold of and I don't think one could ever reach it. Or maybe there are 4 huge turtles out there somewhere after all.

The Frumious Bandersnatch

So what is the universe expanding into?

Or maybe there is nothing it is expanding into?

Perhaps nothing is really real?

Maybe reality is just a figment of dimentional imagination.

Confused

Today at 02:14 PM webboffin said this in Post #87

So what is the universe expanding into?

Or maybe there is nothing it is expanding into?

Perhaps nothing is really real?

Maybe reality is just a figment of dimentional imagination.

Confused

Click to expand...

I guess it is expanding into the spacetime it is creating as it expands.  It makes one's head spin doesn't it. 

Here are a couple more attempts at explanation.

http://www.sciam.com/askexpert_question.cfm?articleID=000CBA20-7D6F-1C72-9EB7809EC588F2D7

Usually we consider the big bang to be the beginning of time and space, and so it is meaningless to ask what existed before or what lies beyond the expanding universe. Because space itself is intimately connected with matter in the universe, as matter was created in the big bang, so was space. There is no 'empty space' that the universe is expanding into.

Click to expand...

http://www.ncsu.edu/felder-public/kenny/papers/cosmo.html

What about a finite universe? This phrase sounds like a contradiction because if the universe ends somewhere then we would naturally want to know what was beyond it, and since the universe includes everything, whatever is beyond that edge should still be called part of the universe. The resolution of this paradox is that even if the universe is finite, it still doesn't have an edge. If I head off in one direction and resolve to keep going until I find the end of the universe, I eventually find myself righ t back where I started. A finite universe is periodic, meaning that if you go far enough in any direction you come back to where you started. Trying to picture a closed (finite) universe is in some ways even harder than trying to picture an open (infinite) universe because it is easy to mislead yourself. For example, people often compare a two-dimensional closed universe to the surface of a bal loon. This analogy is helpful because such a surface has the property of being periodic in all directions, and it is easy to picture the expansion of such a universe by imagining the balloon being blown up. In fact, this analogy is like the rubber sheet a nalogy I used before, except now the sheet has been wrapped up to form a sphere. The problem is that this picture immediately leads to the question of what is inside the balloon. This question comes from taking the analogy too literally. Nothing in general relativity says that a two-dimensional closed universe would have to exist as a sphere inside a three-dimensional space; the theory only says that such a universe would have ce rtain properties (e.g. periodicity) in common with such a sphere. For this reason I think it is useful to keep the balloon in mind as a convenient analogy but it is ultimately best to think of the closed universe as a three-dimensional space with the strange property that things which go off to the right eventually come back again from the left.

Click to expand...

It reminds me a bit of my days studying quantum mechanics.

"Alice laughed: "There's no use trying," she said; "one can't believe impossible things."
"I daresay you haven't had much practice," said the Queen. "When I was younger, I always did it for half an hour a day. Why, sometimes I've believed as many as six impossible things before breakfast."Alice in Wonderland

Click to expand...

Strange as it seems there is quite a bit of evidence for the big bang and predictions made by the theory seem to be born out when tested.

http://news.bbc.co.uk/1/hi/sci/tech/2271377.stm

As to big bang thermodynamics which is more on topic for this thread they are explained on this site.

http://astro.uni-tuebingen.de/~wilms/teach/cosmo/cosmo156.html

It has a lot of math. Don't forget the true nature of math.

The different branches of Arithmetic -- Ambition, Distraction, Uglification, and Derision. Alice in Wonderland

Click to expand...

The Frumious Bandersnatch

Pages and pages of arguing definitons in this thread. Its no wonder we have so much debate in this forum. When you get into terms like Kinds from the Bible the same thing happens.

Today at 09:14 AM webboffin said this in Post #87

So what is the universe expanding into?

Or maybe there is nothing it is expanding into?

Perhaps nothing is really real?

Maybe reality is just a figment of dimentional imagination.

Confused

Click to expand...

The universe is expanding into nothing.  That is, spacetime is expanding.  What we think of as "space" -- the 3 dimensions of x,y,and z coordinates -- is expanding.

So what's your problem with "nothing" being real?  It's a hard concept to grasp, but that has more to do with our understanding and imagination than reality.

Today at 09:45 AM Frumious Bandersnatch said this in Post #88

I guess it is expanding into the spacetime it is creating as it expands.  It makes one's head spin doesn't it. 

The universe is spacetime.  It is that spacetime that is expanding.

As to big bang thermodynamics which is more on topic for this thread they are explained on this site.

Having all the matter/energy/spacetime in one place represents the minimum possible entropy or the maximum "order".  I like to try to explain it as compressed gas in a gas cylinder. Release the gas and entropy increases.  Expand the universe and entropy increases.

27th March 2003 at 10:42 PM DNAunion said this in Post #82



DNAunion: Thanks but no thanks. I already have college physics books that tell me all I need to know about it. You got any?

Click to expand...

If your college physics books are teaching thermodynamics, they should be discussing the Carnot cycle, since it was the Carnot cycle that led to the definition and equations on entropy.  It would appear that "your" textbooks are incomplete.

Today at 10:01 AM Lanakila said this in Post #89

Pages and pages of arguing definitons in this thread. Its no wonder we have so much debate in this forum. When you get into terms like Kinds from the Bible the same thing happens.

Click to expand...

Lanakila, welcome to how science works.  (Altho I wouldn't call what DNAunion does "science".)

Scientists argue.  And they will argue anything they possibly can. Any position that isn't nailed down by data to the point where argument is impossible.  The disagreements in this forum are a love fest compared to any scientific meeting where a controversial subject is being discussed (and that's all of them). 

See the book The Evolutionists by Henry Morris (no, a different Morris from the creationist) for a summary of the bitter arguments between Gould and Dawkins.

So, when scientists agree on a theory -- Big Bang, common ancestry, natural selection as source of adaptations, old earth, etc. -- you can be sure that they do so because they have no choice.

Conspiracies are impossible in science.  Too many independent people who get fame by showing their peers and contemporaries to be wrong.

Lucaspa: If your college physics books are teaching thermodynamics, they should be discussing the Carnot cycle, since it was the Carnot cycle that led to the definition and equations on entropy.

Click to expand...

DNAunion: And yet the Carnot cycle is virtually irrelevant to the main discussion in this thread.

The definition of entropy that is applicable doesn't deal with the quantity of heat entering or leaving a system in a reversible process, divided by the absolute temperature. The entropy being discussed is the one from statistical mechanics: you know, dealing with disorder.

Here, take a look at part of the opening post in this thread.

Entropy (disorder) always increases or remains constant in a closed system.

...

The Law of Entropy, that is, disorder, is a dagger aimed at the heart of Darwinian fundamentalism.

Click to expand...

Lucaspa: Conspiracies are impossible in science.

Click to expand...

DNAunion: What? Then why hasn't Sidney Fox won that Nobel Prize yet for creating life from nonlife? Surely it's because of that conspiracy you keep talking about. LOL!!!