Valentine Pontifex

This is correct. You know, you actually spelled Majipoor correctly.

Automaton

Erica, I believe you deserve a Nobel prize for your incredible work on thermodynamics that rivals that of Ilya Prigogine!

Perhaps if you don't like being flamed, you should at least try to come up with a half-worthy argument instead of wasting the II bandwidth with such nonsense. Or better yet, realise that you're living in a world of delusion, and you accept or deny arguments not on their logical merit, but whether or not they conflict with your preconceived dogma.

Oolon Colluphid

Now now Automaton. Erica's quite nice and, it has seemed previously, willing to learn in the face of creationist drivel. Give her a chance!

Welcome back Erica, BTW.

Ref your question, this is a standard creationist argument against evolution, and shows a fundamental lack of understanding of basic physics. I’m not blaming you, but once again you need to be aware that creationist sources are... how shall I put it? ... unreliable The simple reply is, where do you mean?

This ‘order’ and ‘disorder’ business arise from various ways of looking at the 2nd Law of Thermodynamics. This is variously formulated in textbooks, and it can be rather confusing. The standard work on it says: “No process is possible in which the sole result is the transfer of energy from a cooler to a hotter body.” (Atkins, 1984, The Second Law.) What it amounts to however is that the 2nd Law states that the entropy, that is, the unusable energy, of the overall setup, the ‘system’, can only ever increase. ‘Disorder’, though approximately equate-able with entropy, is a potentially misleading extrapolation.

The classic example of the 2nd Law is a heat engine:

“In all heat engines energy is taken in as ‘high-grade’ energy and only some of it is converted into useful work, the remainder being emitted as ‘low-grade’ energy at a lower temperature.” (Keith Gibbs, Advanced Physics, CUP 1988.)

“The internal energy of an isolated system is constant.” (Francis Azzopardi and Brian Stewart, Accessible Physics for A Level, MacMillan 1995.)

A heat engine, things like petrol and diesel engines, gas turbines and steam engines, is a device that converts heat energy into work. To put it formally, it turns a quantity of heat energy, q1, at temperature, T1, into work w. By the second law, however, the conversion can never be complete. Some of the heat energy that comes out at the end of the process, called q2, will always be wasted, and can be regarded as discharged into a heat sink at a temperature T2. In cars, the heat sink is the radiator.

What equations based on the 2nd Law are used for in relation to engines is to derive the efficiency of the engine -- how much or little of the initial energy input is being lost to entropy. It is taken for granted that there is an input of known quantity, that there is an original heat source. As Gibbs and Muncaster say, “energy is taken in”, and “only because [the] units are consuming energy” does the system work as required.

“If the second law were not true, it would be possible to run ships on heat extracted from the sea. It is not possible to do so, though, because the second law requires there to be a reservoir at a lower temperature than the sea into which some of the rejected heat can be discharged. There is no such reservoir, except perhaps the ship’s cold-store, and this is cold only because refrigeration units are consuming energy to keep it so!” (Roger Muncaster, A-Level Physics, 4th edition, Stanley Thornes 1993.)

But where does the input come from? From outside the engine system, of course. An engine needs a constant supply of fuel. So a heat engine is what is called an ‘open’ system, with a subsection that may be considered ‘closed’ for some purposes. “The internal energy of an isolated system is constant.” (Azzopardi and Stewart.) But an engine is constantly taking in energy in order to keep going, so it’s not isolated.

Where does the fuel come from? Energy can’t be created or destroyed, only converted (that’s the 1st Law of Thermodynamics) -- it has to come from somewhere. Frequently it is from fossil fuels -- fossilised stores of energy from the sun. Or from burning wood – energy from the sun that has been fixed into plant tissues. Or from nuclear reactions, or geothermal actions – from the formation of the solar system, or the universe. If you look at the universe as a whole, there are localised sources of energy: stars. Their energy is gradually becoming spread out, dissipated, lost to heat and entropy. But where there is a source of energy, these localised areas can go against the second law’s overall trend.

There is always an energy loss to entropy at each energy conversion. Whichever source you use, it originates outside the system that’s being measured, ultimately from the big bang. The earth with the sun is a reasonable approximation of a closed system. An engine with its fuel supply is also good approximation. As long as the fuel supplies (the sun, or the petrol) remain available, you can do calculations on a subsystem. But overall, energy is being lost to entropy. You have to take into account all the bodies involved. The second law describes the ultimate fate of all the energy in the only utterly closed system, the universe, as being lost to entropy. There is no problem however in local areas bucking the trend by exploiting an energy source. Life on earth, and its evolution, do this with the sun’s energy (or sometimes geothermal energy).

Fully understood, the second law refers only to closed systems. It is only the entropy of a complete, closed, system that must increase when a spontaneous change occurs. For example, it is a fundamental axiom of thermodynamics that when heat flows from subsystem A to subsystem B, the entropy -- the disorder, if you like -- of A decreases and the entropy of B increases. Only in the overall picture is there an increase in entropy.

Going back to order and disorder... in nature, order arises from disorder all the time. Snowflakes, all different and all with six-sided symmetry, form spontaneously from randomly moving water molecules; salt crystals with precise planes of symmetry grow when water evaporates from solution; seeds sprout, and a human body grows from the relative formlessness of a fertilised egg. Can your see now what's going on?

It's that the same applies to living organisms. They are not closed systems, because they constantly need to take in nutrients (= energy) to survive. And so do their offspring, which may vary from their parents, often with heritable differences. So do their cells; so do mitosis and meiosis. So do the adults that fused gametes grow into. This energy ultimately derives from the beginnings of the universe.

While for some purposes many systems may be thought of as closed, such as an engine with a ready fuel supply, an organism in its total environment, the earth-sun system, and so on, none of them really absolutely are. The only truly, ultimately closed system is the universe itself.

Neither an organism, nor its cells, nor its environment, nor anything else except strictly the universe itself, is a closed system. If you put a cat, for instance, in a closed system such as a sealed box a la Schrodinger and leave it a few weeks, its entropy will increase in accordance with the second law. You can tell that the earth is not a closed system by getting up in the morning and looking eastwards. That big bright hot thing in the sky is a bit of a giveaway.

The sun is increasing its entropy all the time, and the earth is the beneficiary of this: systems on it can decrease their disorder without violating anything. When the sun finally uses up all of its nuclear fuel and winks out as a charred cinder, leaving this region of space utterly cold and barren, the earth-sun system’s entropy debt will be paid in full. But not just yet.

Organisms spend their whole lives -- one might say by definition -- working against the second law. Eventually, they stop working against it, and the second law takes over -- they die, and decompose to a less organised state. If an oak tree can have rather more usable energy and organisation than the acorn it came from, what is to stop its own acorns not be able to produce trees with even better organisation? And their trees? And theirs? Certainly not the second law of thermodynamics.

Natural selection is a powerful opponent of the thermodynamic tendency toward disorder. Organisms are programmed by their DNA to synthesise complex molecules, with the help of the sun's energy (available because they're not closed systems). The genetic information changes by mutation, which if unopposed would break down the order of a living system. But natural selection maintains order by preserving unmutated copies of DNA (because they work), and any mutations that improve the survival chances (increase organisation -- work better), while eliminating those mutations that decrease survival/reproduction chances (cause disorganisation).

In other words, entropy does have the expected effect on living things, but natural selection means that only those individuals that are unaffected -- or positively affected! -- get to continue passing on their genes. The tendency towards disorder from the second law, far from making evolution impossible, is one of the key elements that makes evolution possible!

Evolution isn't some separate thing out there, which could of itself break any laws or not. It is what happens to lineages of organisms.

So evolution no more breaks the second law of thermodynamics than you break the law of gravity by jumping up. As Isaac Asimov has put it, the creationist argument from the second law is “an argument based on kindergarten terms [that] is suitable only for kindergartens”.

Hope this clears it up. Others here can give you a better understanding of the maths side of it if it helps.

Best wishes, Oolon

[ February 20, 2002: Message edited by: Oolon Colluphid ]</p>

Kosh

Hey, never thought of it like that before.
We're already on solar power! It's just that
our batteries suck...

Writer@Large

All this talk of order, disorder, and entropy, and no one's yet pointed Erica to <a href="http://artists.mp3s.com/artists/165/mc_hawking.html" target="_blank">MC Hawking</a>? Erica, go <a href="http://artists.mp3s.com/artists/165/mc_hawking.html" target="_blank">here and scroll down</a> to the fourth song.

(You think I'm joking, but the song is actually quite well-crafted as a simplified explaination ... if you can get past that grating voice! )

--W@L

bluefugue

That was a monster post, Oolon.

HRG

The problem, of course, is that your definition is full of entirely subjective terms like "proper functioning/appearance", "methodical/prescribed" or even "component parts".

Are the water molecules in a snowflake "methodically arranged" so that it has the "proper appearance" ? In that case, natural processes can create order.

What is the "proper functioning" of a gas which is filling a vessel ? If this is "expansion", then the molecules within the gas are ordered and expansion (an entropy increase) is an emergence of order.

IOW, order is largely in the eyes of the beholder.

Regards,
HRG.

Oolon Colluphid

What, huge, badly formed and cobbled together from various sources? Yeah, I thought so! I’m sure there was a concise post in there struggling to get out

Cheers, Oolon ‘Victor Frankenstein’ Colluphid

Oolon Colluphid

[ Amid the throng of others in the puddle, one water molecule started talking to another. He pointed out just how wonderfully the ground fitted the water. It was the perfect depth to accommodate them all. Each bump and dip of the water's edges, the ground curved to meet. It fitted them, we humans might say, like a glove. The fit was so perfect, said the molecule, that it was certain evidence of a puddle designer.

The other molecule was not impressed. He had noticed that the sun had come out.

TTFN, Oolon

[ February 20, 2002: Message edited by: Oolon Colluphid ]</p>