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

Frumious Bandersnatch

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Instead, entropy applies to all systems. Life is not an exception. The reason it is not is because all calculations of entropy must consider not only the system being focused on but the surroundings. When you do that, what I am saying is that the totality of system and surroundings always increases in entropy, even tho the system decreases.

To avoid problem with exactly what the surrounding are I just consider the "surroundings" of a non-isolated system to be the rest of the universe. Then there is no ambiguity as every non reversible process increases the entropy of the universe (and every real process is non reversible to some extent).

For a really confusing fact about classical entropy consider that while it always increases in irreversible processes it can only be calculated using reversible changes. Try explaining exactly why that is to students some time.

The Frumious Bandersnatch
 
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Frumious Bandersnatch

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Frumious Bandersnatch: If you are going to call a closed system isolated you should specify that it is adiabatically closed especially when you give the standard definition of a closed system, that is not isolated in a subsequent. 


DNAunion: Huh? The first part made sense - though it was wrong - but the last part made little sense.

The first part is correct.  In the second part I meant to say subsequent post, I accidently left out the word post when I was changing some wording around. I was referring to these definitions posted by DNAunion in post 49 of this thread.
Thermodynamic Systems
A thermodynamic system is that part of the universe that is under consideration. A real or imaginary boundary separates the system from the rest of the universe, which is referred to as the surroundings. Often thermodynamic systems are characterized by the nature of this boundary as follows:

Isolated systems are completely isolated from their surroundings. Neither heat nor matter can be exchanged between the system and the surroundings. An example of an isolated system would be an insulated container, such as an insulated gas cylinder. (In reality, a system can never be absolutely isolated from its environment, because there is always at least some slight coupling, even if only via minimal gravitational attraction).

Closed systems are separated from the surroundings by an impermeable barrier. Heat can be exchanged between the system and the surroundings, but matter cannot. A greenhouse is an example of a closed system.

Open systems can exchange both heat and matter with their surroundings. Portions of the boundary between the open system and its surroundings may be impermeable and/or adiabatic, however at least part of this boundary is subject to heat and mass exchange with the surroundings. The ocean would be an example of an open system. “
I added some bolding to refresh your memory of the standard definition of a closed system, which you were kind enough to provide. So you can see from the definitions that you posted that if you want to call a closed system isolated as you have done you must specify that it is adiabatically closed (can't exchange heat). Otherwise it can exchange energy with its surroundings.  Added in Edit: You could just say adiabatic closed system, which means the same thing.

The Frumious Bandersnatch
 
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Fruminous Bandersnatch: I added some bolding to refresh your memory of the standard definition of a closed system...

DNAunion: But that's not THE standard definition of a closed system. There are TWO definitions of a closed system: it depends upon whether the dichotomous or trichotomous classification is being used. When using the dichotomous classifications (open vs closed), a closed system is one for which neither energy nor matter enters or exits - that is, it is an isolated system in the other classification scheme.

The original poster obviously meant this type of closed system - I eliminated any possible ambiguity by correctly qualifying "closed system" by adding the term isolated.

Fuminous Bandersnatch: So you can see from the definitions that you posted that if you want to call a closed system isolated as you have done you must specify that it is adiabatically closed (can't exchange heat).

DNAunion: Wrong. See above.
 
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lucaspa

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20th March 2003 at 11:08 PM DNAunion said this in Post #60

DNAunion: Lucaspa, note that your own author used double quotes around the term isolated system.



DNAunion: Double quotes around a term typically indicates nonstandard usage.

What that author gave is not a definition of an isolated system. If you want one, reread the posts I made earlier tonight in this thread - you'll find several.

Why are you continuing to argue the semantics?  Leaving aside your irrelevancy about double quotes, an isolated system includes the system and surroundings.  Since the surroundings are anything that can interact with the system, this is simply another way of saying what your "definitions" say.

Actually, your qoutes from Gribbin and Hawking didn't define an isolated system.  They just pointed out that the universe as a whole is one.
 
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lucaspa

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20th March 2003 at 11:42 PM Frumious Bandersnatch said this in Post #61



To avoid problem with exactly what the surrounding are I just consider the "surroundings" of a non-isolated system to be the rest of the universe. Then there is no ambiguity as every non reversible process increases the entropy of the universe (and every real process is non reversible to some extent).


That's one way of doing it.  But then you are doing as Barrow advocates, looking at system under study and the surroundings.  As DNAunion's quotes show, everyone is agreed that the universe as a whole is a closed system.  The entropy of the universe as a whole does increase while some systems decrease entropy. 



 
 
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Lucaspa: ... an isolated system includes the system and surroundings.

DNAunion: No it doesn't. The surroundings are not part of the system under consideration.

Lucaspa: Since the surroundings are anything that can interact with the system, this is simply another way of saying what your "definitions" say.

DNAunion: No it's not. By definition, the surroundings of an isolated system do NOT interact with the system.
 
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Frumious Bandersnatch

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DNAunion: But that's not THE standard definition of a closed system.
Then why did YOU give it to us? :confused: ;)

It may not be THE standard definition but it is the definition in the texts that I have used to study thermodynamics. For a recent example you can see page 4 of MODERN THERMODYNAMICS: From Heat Engines to Dissipative Structures by Dilip Kondepudi and Ilya Prigogene, John Wiley and Sons, 1998 which gives the definition of a closed system as one that can interact with a thermal reservoir but not exchange matter.  The fundamentals of thermodynamics are nearly always derived using systems (heat engines) that are closed but not isolated.  I would guess that you can also find these definitions on dozens if not hundreds of web pages and books on thermodynamics. Here are a couple more examples in addition to the three that you gave which all say the same.

http://class.fst.ohio-state.edu/FST822/lectures/Thermo.htm
http://www.ncusd203.org/north/depts/science/chem/marek/apintropage/ap_notes/chapter7/chapter7.htm

This is why you must specify that a system is adiabatic (which essentially means closed to any energy flow since any energy can be converted to heat) if you mean that it is isolated.

In chemistry open, closed and isolated systems are defined separately because closed systems that allow only heat flow without matter flow behave quite differently from either isolated (no flow of either) or open (flow of both) systems. For example a clear distinction must be drawn between Carnot cycles in closed systems and the adiabatic expansion of a gas in an isolated system. 

Chemists nearly always define the three types of systems explicitly. Physicists may not. Enrico Fermi in Thermodynamics written in 1936 does not specifically list all three types of systems but when he refers to systems with no matter or energy flow he always calls them isolated systems and not closed systems. I am not sure where what you call the dichothomous nomenclature arose but I don't happen to like it (I couldn't open the link you gave to some previous discussion). However, as long as you specify that a closed system is also adiabatic (as Badfish did in the first post) you are formally correct to call it isolated.

Now let me try to straighten out this systems + surrounding = isolated system thing that Lucaspa quoted from Barrow. First Barrow is saying that a closed system interacts with its surroundings but the two together may in some cases be considered isolated if they don't affect anything else. I'll try to explain what I quite sure that he means, though I don't have the book here at home.  Let's say those surroundings of the closed system consist entirely of a single heat reservoir. If you then isolate the heat reservoir to the outside world so that it can only exchange heat with the closed system in question and the system can only exchange energy with the reservoir, then the reservoir plus the closed system are in total adiabatic. In this case you can consider the  reservoir plus the system an isolated system but this is only true if the original closed system and the reservoir cannot exchange matter or energy with anything else in the universe.  You could have more than one heat reservoir and still have an isolated system in total, as long as the closed system and everything (the reservoirs) that it can possibly exchange energy with are isolated from the rest of the universe.  The entropy of the closed system can decrease but the entropy of the closed system plus the reservoirs must increase in any real process if the reservoirs are isolated from everything but the system.  

I would like to point out again that this somewhat pointless argument about semantics is irrelvant to evolution which occurs in an open system.  I happen to think that it is also irrelevant to the big bang whether the universe is isolated or not.  Entropy can be equated to (E+PV)/T . Now consider that the temperature has probably dropped from few trillion degrees to 2.7 K, E is constant since the bang and while P has decreased a lot V has inreased to the current size of the universe so it seems to me that S must have increased increased overall as a result of the big bang if such a thing actually did occur as current theory indicates.  

The Frumious and somewhat pedantic Bandersnatch.
 
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Frumious Bandersnatch: Then why did YOU give it to us? :confused: ;)

DNAunion: Because it is A valid definition (note, it's not 'THE' definition). Of the TWO valid definitions, which one is used at a given time depends upon the context of the discussion at that time.

Frumious Bandersnatch: This is why you must specify that a system is adiabatic (which essentially means closed to any energy flow since any energy can be converted to heat) if you mean that it is isolated.

DNAunion: Wrong. If someone means it is isolated, all he/she has to do is say that it is isolated: as I did.
 
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Frumious Bandersnatch: I am not sure where what you call the dichothomous nomenclature arose but I don't happen to like it ...

DNAunion: But that doesn't make it go away.

Here are some instances of .edu sources using a dichotomous classification of systems (note the point I am making here!).

”Depending on whether or not a system can exchange energy with the surroundings is it said to be open or closed.” (http://www.biologie.uni-hamburg.de/b-online/e18/18a.htm)

“Open (closed) system – exchange of matter is (is not) allowed” (http://bama.ua.edu/~gzangari/courses/MTE252/lectures/5 Intro to Thermo.pdf)

“An open system is one in which matter and energy are exchanged with the surroundings. Precipitating clouds are a good example of an open system. A closed system does not exchange mass with its surroundings.” (http://itg1.meteor.wisc.edu/wxwise/museum/a5/a5descript.html)

”1st Law of Thermodynamics
6) Closed Systems
Recall our definition:
Open vs. Closed: Mass may transfer in and out of an “open” system, unlike a closed system.” (http://www.ims.uconn.edu/~mather/cheg211b_files/CHEG211 Lecture 4 (28Jan2003)%20Template.pdf )


DNAunion: These don't give "definitions" as the above did, but they mention only closed vs open systems.

“2. Energy, energy transfer, work, first law of thermodynamics for open and closed systems, zeroth law of thermodynamics (1.5 weeks)” (http://www.bu.edu/ame/abet/abet02-03/ek304-03.html)

”Students learn about internal energy, enthalpy, entropy, open and closed systems, flow work, the First Law (conservation of energy) Second Law (entropy always is increasing) and how these concepts are used to analyze systems and processes.” (http://che.oregonstate.edu/che311.htm)


”Course Objectives:
…
To apply the first law of thermodynamics to a closed as well as to an open system.
To apply the second law of thermodynamics and the energy balance to a closed as well as an open system.” (http://www1.coe.neu.edu/~yal/mim1280.html)

”Students will demonstrate an understanding of the basic concepts of thermodynamics such as closed and open systems, properties of a system, …” (http://www.ces.clemson.edu/me/studentinfo/undergrad/syllabus/ME310.pdf)

First Law for Closed Systems: …
First Law for Open Systems: …
( http://thermal.sdsu.edu/testcenter/Test/problems/problems.html )
 
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Frumious Bandersnatch

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DNAunion: Because it is <B>A</B> valid definition (note, it's not <B><I>'THE'</I></B> definition). Of the <B>TWO</B> valid definitions, which one is used at a given time depends upon the context of the discussion at that time.

Whether a system is closed only or truely isolated does not depend on context.&nbsp; Closed is only a valid&nbsp;way to refer to&nbsp;an isolated system if it is also specified that the system is adiabatic.

Frumious Bandersnatch: This is why you must specify that a system is adiabatic (which essentially means closed to any energy flow since any energy can be converted to heat) if you mean that it is isolated.

DNAunion: Wrong. If someone means it is isolated, all he/she has to do is say that it is isolated: as I did.

Yes, if you say it is isolated, but my point is that when&nbsp;one refers to a closed system when&nbsp;one means isolated system, as Badfish did then&nbsp;one must specify that the system is adiabatic as well as closed(which Badfish also did). I forgot this one time to say that I was referring to the usage where closed system is meant to refer to an isolated system. I am sure that this is what you meant when you wrote closed (isolated)&nbsp;but why not just write isolated in the first place&nbsp;to avoid any chance of confusion??&nbsp;&nbsp;If one&nbsp;wants to be really picky about it the terminology &nbsp;"closed (isolated)" &nbsp;is not really correct. If you meant closed and adiabatic then there is no need to write (isolated) but you should write adiabatic&nbsp;and if you meant closed only then the system is not isolated.&nbsp;&nbsp;
&nbsp;
 
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Frumious Bandersnatch: I forgot this one time to say that I was referring to the usage where closed system is meant to refer to an isolated system. I am sure that this is what you meant when you wrote closed (isolated) but why not just write isolated in the first place to avoid any chance of confusion?

DNAunion: Because I was repeating what the original poster said!

But to eliminate the potential ambiguity in his statement, I modified it by adding the explanatory "(isolated)".
 
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Frumious Bandersnatch

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Here are some instances of .edu sources using a dichotomous classification of systems (note the point I am making here!).

quote:
”Depending on whether or not a system can exchange energy with the surroundings is it said to be open or closed.” (http://www.biologie.uni-hamburg.de/b-online/e18/18a.htm)

This one is the only one which explicitly says that a closed system can't exchange energy.

1st Law of Thermodynamics
6) Closed Systems
Recall our definition:
Open vs. Closed: Mass may transfer in and out of an “open” system, unlike a closed system.” (http://www.ims.uconn.edu/~mather/ch...0Lecture%204%20(28Jan2003)%20Template.pdf )

I can't open the link but where does it say that closed systems can't transfer energy?

An open system is one in which matter and energy are exchanged with the surroundings. Precipitating clouds are a good example of an open system. A closed system does not exchange mass with its surroundings.” (http://itg1.meteor.wisc.edu/wxwise/...a5descript.html)
You needed to read on in this one
If we define a planet as a closed system, the only way it can exchange energy with its environment, space, is through the transfer of radiation
They are treating the earth as a closed system that can transfer energy but not mass by ignoring the small amount of mass that is transferred.

First Law for Closed Systems: …
First Law for Open Systems: …
( http://thermal.sdsu.edu/testcenter/...s/problems.html )
You needed to read this one further as well:
First Law for Closed Systems: Problems involving a closed system undergoing a process. Given information about the initial state, final state and system/surrounding interaction (such as heat or work transfer), to find the missing quantity with the help of first law analysis. Similar problems can be found in Chapter-3 of most standard textbooks.

You can see that they are also defining closed systems as ones that can transfer heat to their surroundings.&nbsp; They also say that similar problems can be found in most standard textbooks.&nbsp; I suspect the textbooks in for the courses you pointed to use the standard definition of open, closed and isolated but I could be wrong as I have not read them but I have read several texts in this area and they all define systems as open(mass and energy), closed(energy only)&nbsp;and isolated.&nbsp;

So yes, occasionally closed systems are said to not transfer energy or mass which means that they are isolated. I think I ackowledged that in a earlier post.&nbsp; However, I maintain that the standard nomenclature of chemical thermodynamics refers to closed systems as those that transfer energy but not mass. All the heat engine analysis used to define and teach basic thermodynamics is done using such systems(Carnot cycles).&nbsp; I further maintain that if you really mean isolated system when you say closed system you must be careful to specify, as the first&nbsp;website you point to does, that the system does not transfer energy. However, if you insist on writing closed(isolated) when you just mean isolated go right ahead&nbsp;we&nbsp;should&nbsp;certainly all know what you mean by now.&nbsp;

The Frumious Bandersnatch
 
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DNAunion: Alas, we see that Frumious Bandersnatch is more interested in arguing than in trying to understand.

In case you somehow missed it Frumious...

DNAunion: Here are some instances of .edu sources using a dichotomous classification of systems (note the point I am making here!).

DNAunion: Your "counters" to my instances of .edu sources using a dichotomous classification of systems are irrelevant. Can you see why?
 
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Frumious Bandersnatch

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DNAunion: Alas, we see that Fruminous Bandersnatch is more interested in arguing than in trying to understand.

Hmm. Did you ever hear the one about the pot and the kettle? I'll admit that I like to argue but I never said the "dichotomous classification" didn't exist. I said I didn't like it and that I didn't know how it arose. I also say that it is not standard in chemical thermodynamics. I really don't see how you do basic thermodynamic analysis with closed systems that don't transfer energy. I guess you need two kinds of "closed" systems, adiabatic and non adiabatic closed systems, but I don't see the point. Unless you can explain how to do a completely adiabatic Carnot cycle.

Anyway, I'll teach my students themodynamics my way and you can feel free to teach yours any way you want.


The Frumious Bandersnatch
 
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DNAunion: And now, ladies and gentlemen, the quote you've all been waiting for....drumroll please....

"A closed system is one that does not exchange energy or matter with its surroundings, whereas an open system is one that can exchange matter and energy with its surroundings." (Eldra Pearl Solomon, Linda R. Berg, & Diana W. Martin, Biology: Fifth Edition, Saunders College Publising, 1999, p136)
 
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Frumious Bandersnatch

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Like I said, I don't dispute that this definition of closed system exists, in fact I believe that I said that is not only exists but it is a source of confusion because it is different from the standard definition used in chemistry. It looks to be popular in biology for some reason. So now, suppose we are going to try to teach some thermo with this definition. Do we run a Carnot cycle to explain the second law in an open system? No that won't work because mass flow can mess things up. Do we do it in a "closed" system as defined here. No we can't because heat flow is obviously needed for a heat engine. Looks like we're stuck. That's why I prefer the standard definition of open, closed and isolated which is found in all the texts that I have used to either study or teach thermodynamics.

The Frumious Bandersnatch
 
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DNAunion: But it's not restricted to biology.

"The second law of thermodynamics says that the total entropy of any closed system must either remain constant or increase with time; it can never decrease." (Melvin Merkin, Physical Science with Modern Applications: Fifth Edition, Saunders College Publising, 1993, p160)

DNAunion: That isn't true if we use the definition of a closed system from the trichotomous classification scheme. And I can "prove" it.

Take two identical plastic bottles and fill each of them partially with water, then place lids tightly on each. These are closed systems: energy can enter and exit, but matter cannot. Now, put one in a freezer for an hour and another in the microwave for a couple of minutes. What happens? Sure enough, the one placed into the microwave had an increase in disorder (entropy) since the added energy increased the average kinetic energy of the molecules, making them more "chaotic". But the one placed in the freezer had a DECREASE in disorder (entropy). It gave off heat to the surroundings and its molecules became more ordered as they slowed down and began to form more-rigid, crystal-like stuctures.

Thus, it is NOT true that "the total entropy of any closed system must either remain constant or increase with time".

That statement, however, IS true for an isolated system.

Therefore, the author of that physical science text is implicitly equating the term "closed system" with the term "isolated system" used in the trichotomous classification.
 
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Frumious Bandersnatch

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Take two identical plastic bottles and fill each of them partially with water, then place lids tightly on each. These are closed systems: energy can enter and exit, but matter cannot. Now, put one in a freezer for an hour and another in the microwave for a couple of minutes. What happens? Sure enough, the one placed into the microwave had an increase in disorder (entropy) since the added energy increased the average kinetic energy of the molecules, making them more "chaotic". But the one placed in the freezer had a DECREASE in disorder (entropy). It gave off heat to the surroundings and its molecules became more ordered as they slowed down and began to form more-rigid, crystal-like stuctures.

Thus, it is NOT true that "the total entropy of any closed system must either remain constant or increase with time".

Of course it isn't. Who said it was? I know this and I know how to calculate the magnitude of the entropy changes and I learned&nbsp;how using the standard definition of closed systems as those that exchange energy and not mass. &nbsp;

I am beginning to wonder if you even know what a Carnot cycle is or how Clausius used the Carnot cycle to define entropy. It is taught in every basic course on thermo as far as I know. My point is that you can't do the type of elementary thermodynamics required to illustrate classical entropy and entropy changes, calculate efficiency of heat engines or explain the use of a gas thermometer to get absolute temperature, for example with closed systems that are defined as isolated. This is why I have always used the distinction between closed and isolated systems that I learned in PChem in college and Grad School, when either doing&nbsp; calorimetery&nbsp;or teaching thermodynamics. Feel free to use the&nbsp;dichotomous definition&nbsp;if you want since you probably don't have to explain Carnot cycles to anyone.&nbsp;

I think enough has been said about this subject.&nbsp; I plan to go back to arguing about creationism. Here are&nbsp;some pages illustrating the use of the Carnot cycle to explain entropy.

http://cstl-cst.semo.edu/venezian/PH230/second_law_of_thermodynamics.htm

http://www.andrew.cmu.edu/course/24-221/second-law.pdf

I am sure you will have to get in one last post. Have at it.

The Frumious Bandersnatch
 
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DNAunion: Thus, it is NOT true that "the total entropy of any closed system must either remain constant or increase with time".

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?

Frumious Bandersnatch: I know this and I know how to...

DNAunion: Who said you didn't know that statement was "wrong"?

Nowhere did I say that you said, or thought, that "the total entropy of any closed system must either remain constant or increase with time." But you seem to have taken my statement personally, somehow.

My showing the AUTHOR's statement to be "wrong" was part of a chain of logic leading up to showing that the author equated "closed system" with "isolated system". Here, take another look.

DNAunion: Thus, it is NOT true that "the total entropy of any closed system must either remain constant or increase with time".

That statement, however, IS true for an isolated system.

Therefore, the author of that physical science text is implicitly equating the term "closed system" with the term "isolated system" used in the trichotomous classification.

DNAunion: Do you now see the point I was making? Do you see now that I wasn't claiming you made that statement?
 
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18th March 2003 at 12:44 AM Badfish said this in Post #4



If everything is in a state of entropy, and more species have died than have lived, why doesn't it have anything to do with evolution?

If the Universe was spontaneously created or brought forth into existence (or even if it came or evolved from an unknown singularity, maybe a creator?), then something created this reaction.

Since our bodies are made up of all the elements found in the Universe, I think this could have some insight to how mankind came to be.

The process of evolution still had to have an origin (a singularity if you will), where did that origin come from? Where did the first microbial come from?

How did life create itself, regardless of evolution? Our world and the law of Entropy could support the idea of intelligent and unique specimen design.

Entropy exists and it suggests things are devolving, could this not be a consideration for some kind of creation?


Well the singularity really has nothing to do with evolution. \
 
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