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Author
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Topic: The Theory of evolution in the Perspective of Thermodynamics and Experience-de Jong
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kyle7
Member
Member # 191
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posted 04. June 2006 01:20
quote:
Let's go through the numbers in a simple scenario:
Suppose we have a liter of water at room temperature. The standard entropy of water is 70 J/molK, and its molecular mass is 16+1+1=18. Since water weighs 1 kg/liter, the entropy of the liter of water is: 1 kg * (70 J/molK) / (.018 kg/mol) = 3889 J/K.
Now suppose we pour the water from its container into random puddles on the table. What is the final entropy of the water?
Given the fact that the molecules are identical (and neglecting the details of the process with the assumption that it is adiabatic) the entropy would be the same.
Now suppose we have two containers with the same volume of water at the same temperature. If the one case we poured out the water in separate puddles and added dye colors to the different puddles and the other case we mixed all the dyes into one container, which would have he greatest entropy?
2ndclass says the following:
quote:
The second, more significant error is in the definition S = k Ln W, with W defined as "the probability of the state of a system." Since W is always less than one, this yields a negative value for S, which makes no sense.
The W is "the total number of possible microscopic states available to a system and is called the thermodynamic probability" [1].
[1] "Engineering Thermodynamics" Moran & Shapiro
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Zachriel
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Member # 1793
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posted 04. June 2006 09:46
kyle: "Given the fact that the molecules are identical (and neglecting the details of the process with the assumption that it is adiabatic) the entropy would be the same."
The toy blocks are identical also. Do you now claim that blocks being in the toy box or scattered on the floor have the same entropy?
And can you put any difference in J/mol.K?
[ 04. June 2006, 09:47: Message edited by: Zachriel ]
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2ndclass
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Member # 1979
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posted 05. June 2006 11:48
Kyle: quote:
The W is "the total number of possible microscopic states available to a system and is called the thermodynamic probability"
Thank you for pointing that out Kyle. I stand corrected, and I apologize for wrongly challenging William on this point.
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2ndclass
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Member # 1979
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posted 05. June 2006 11:57
William: quote:
Over the interval [t0, t1] a flow of energy passes the boundaries of R to power D, resulting in a positive left term of the second law of thermodynamics and a decrease of the entropy of R.
A positive left term means that the right term, S2-S1, is also positive, i.e. an increase in entropy.
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2ndclass
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Member # 1979
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posted 05. June 2006 12:04
Kyle: quote:
Directed energy is energy utilized to allow nonspontaneous processes to occur.
Solar energy certainly fits this description. Kyle and William, since the sun provides more than enough "directed energy" to account for entropy decreases on earth, how does evolution violate the 2nd Law?
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William DeJong
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Member # 1162
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posted 06. June 2006 07:31
2ndclass : Solar energy certainly fits this description. Kyle and William, since the sun provides more than enough "directed energy" to account for entropy decreases on earth, how does evolution violate the 2nd Law? posted 05. June 2006 12:04
In the experiment described in my post on 03. June 2006 04:44, it was shown:
a. that if the left term of the second law is positive, during the interval [t0, t1], the entropy in the room R decreases (corresponding with the neatly ordering of the scattered gas molecules into two different compartments);
b. that if the left term of the second law is zero, during the interval [t1, t2], the entropy in the room R increases (corresponding with the scattering again of the G1-molecules and G2-molecules over R).
We will now conduct a second experiment, starting at t2, and will investigate what happens if R is put into the sunlight.
Experiment2
On t2, C1 and C2 are filled with the same gas mixture of G1 and G2; D is switched off; V is open. The isolation of the room is removed. R is put into the sun.
Observations
During the interval [t2, t3] the temperature T in R increases. The molecules of the gas mixture start vibrating faster and their radiation of energy increases. Since the isolation of R is removed, the radiated energy leaves R. On t3 equilibrium is reached between the incoming energy of the sun and the outgoing radiation produced by the gas molecules. T stays unchanged now at Teq. No separation of the gas is observed, the molecules stay scattered over both compartments C1 and C2. On t4, D is switched on, and the ordering of G1-molecules and G2-molecules into C1 and C2, respectively, starts. On t5, equilibrium is reached between the separation activities of D and the leak away of separated molecules through the open valve V.
Discussion
During the interval [t2, t3] the left term of the second law is positive, resulting in a decrease of the entropy of R. When T increases, the contribution of the incoming energy flows to the decrease of the entropy abates, since in the left term of the second law the integral of the energy flows that pass the boundaries of R is divided by T. As a result, the higher T the less the contribution of the incoming energy to the decrease of the entropy. This relationship represents an uncomfortable property of reality: "The more energy that has been paid to the ordering of a system yet, the less effective an additional amount of energy".
On t3, equilibrium is reached between the incoming sunlight and the outgoing random radiation of the molecules. From t3 on, the integral resultant flow of energy over the boundaries of R is zero on average. As a consequence, the left term of the second law is zero. (Notice that on each suface element of the boundaries of R, the resultant flow of incoming and outgoing energy is a random function. The integral over the entire boundary of R of all these random flows is zero on average)
During the interval [t3, t4] the left term of the second law is zero on average, and the entropy increases to the highest possible level.
On t4, D is switched on, the left term of the second law turns positive and the entropy decreases.
Conclusions
1. When putting an object into the sunlight, its entropy decreases until equilibrium is reached between the heating of the object and its radiation of energy. On average over the boundaries of the object, random flows of energy are present from that moment, resulting in a zero left term of the second law and an increase of the entropy.
2. The supposition that putting an object filled with scattered molecules into the sun will make the scattered molecules start ordering themselves neatly (corresponding with a decrease of he entropy of the object) is contradicted by the second law of thermodynamics and by everyday experience. Experiment2 show that putting R into the sunlight does not make the scattered molecules start ordering themselves over C1 and C2. (Notice again that entropy is a concept to capture disorder, and is completely different from the concept of energy content)
3. Miller's experiment is another clear example of the flat contradiction between empirical science (and everyday experience where it is based on) with the central supposition of the (macro) theory of evolution that random flows of energy can make molecules start ordering themselves, maintain that order and expand it ever further. Indeed random flashes of lightning can make simple molecules stick together as DNA building blocks. But new flashes of lightning will easily destroy these arrangements, the bigger they are the faster. Random flashes of lightning cannot produce a decrease of the entropy, according to the second law (since the left term is zero on average). Miller experienced this in his initial experiment. Instead of reporting this fundamental property of reality, he added to his experiment a transportation system to put the produced building blocks in safety, resulting in the production of an ever-concentrated organic soup. The Miller-experiment is probably the most deceptive experiment in the entire history of science, and is meant to fool us all.
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Zachriel
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Member # 1793
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posted 06. June 2006 10:02
William DeJong: "The supposition that putting an object filled with scattered molecules into the sun will make the scattered molecules start ordering themselves neatly (corresponding with a decrease of he entropy of the object) is contradicted by the second law of thermodynamics and by everyday experience."
Ok, so I decided to try your experiment. The only difference was I added water to the bottom of the container.
As you indicated, the ambient temperature inside the container increased under the influence of the sunlight. I noticed that some of the water evaporated, and air currents formed. The water condensed into droplets on the sides of the container. I also noticed that different areas of the container were at different temperatures, e.g. the water at the bottom of the container compared to the air at the top of the container.
I decided to try the experiment with a slightly larger container. This time, the air currents formed eddies while cyclonic patterns carried the water vapor up towards the top of the container. There some of it formed complex ice crystals, which grew, fell, and melted again. Other times the container would appear near stasis, but then the wild motions would begin again. This chaotic variation continued as long as the sun shown on the container.
The container was 5 miles high and 100 miles wide.
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Stephen Wright
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Member # 195
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posted 06. June 2006 11:01
Zach,
Ok, now you have weather. Is today’s weather better organized than yesterdays? To what purpose?
If you have a target state – say generating electricity – then more energetic weather can be thermodynamically converted to “juice” by a windmill.
Now all you need is a designer and construction crew to build one and obtain an increase in the output of the target state. Wait you say – chaotic weather can mean lightening strikes where immense electrical charge transfer takes place.
Whoops – at this time electricity from weather is rarely harnessed to a productive state aimed at work. W = Fx
“Back to the Future” as a noted exception. (well - virtually in the movie)
Complexity in a system is not the same as an organized state targeted at a specific goal. Pragmatically, thermodynamics is about productive output as measurable work.
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Zachriel
Member
Member # 1793
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posted 06. June 2006 11:53
Stephen Wright: "Is today’s weather better organized than yesterdays?"
The claim was that such ordering (snowflakes, lightning bolt) was not possible.
Stephen Wright: "then more energetic weather can be thermodynamically converted to 'juice by a windmill."
Actually thunderstorms regularly produce electricity in large quantities.
Stephen Wright: "at this time electricity from weather is rarely harnessed to a productive state aimed at work. W = Fx"
In thermodynamics, water being evaporated and moved up into the atmosphere, or the ionization of atmospheric molecules by lightning is "work", whether you appreciate the value or not. Though rain does have some significant value and makes terrestrial life possible.
Stephen Wright: "Complexity in a system is not the same as an organized state targeted at a specific goal."
Weather is a complex system that harnesses work whether or not it has a goal, or whether you appreciate any such goal.
Stephen Wright: "Pragmatically, thermodynamics is about productive output as measurable work."
Thermodynamic laws are not dependent on your concept of "pragmatic".
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2ndclass
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Member # 1979
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posted 06. June 2006 12:58
William: quote:
In the experiment described in my post on 03. June 2006 04:44, it was shown:
a. that if the left term of the second law is positive, during the interval [t0, t1], the entropy in the room R decreases (corresponding with the neatly ordering of the scattered gas molecules into two different compartments);
quote:
During the interval [t2, t3] the left term of the second law is positive, resulting in a decrease of the entropy of R.
William, this is the third time you've made this same mistake. Please look at the inequality on page 3 of your paper. If the left term is positive, then S2-S1 is also positive, which means that entropy increases during the intervals [t0,t1] and [t2,t3].
quote:
As a result, the higher T the less the contribution of the incoming energy to the decrease of the entropy.
You seem to have the mistaken idea that adding energy to a system decreases its entropy. This is entirely false. Entropy always increases with an influx of energy and decreases with an outflux of energy. If the outflux occurs at a lower temperature than the influx, then the system may experience a net decrease in entropy, according to the 2nd Law.
I think your intuition has misguided you, which is to be expected when dealing with thermodynamics.
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Stephen Wright
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Member # 195
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posted 06. June 2006 14:21
quote:
http://www-spof.gsfc.nasa.gov/stargaze/Swork.htm
“Work - The concept of Work is closely related to that of energy. In fact, the formal definition of energy is "the capacity to perform work." Let us see what this means.
Work is associated with forces that overcome resistance. The work W performed while overcoming a resisting force F over a distance x is defined as F times x
W = Fx
Things to note: F must oppose the motion. If the direction of the vector F differs from the direction of x, then F must be resolved into components parallel and perpendicular to x (in the manner discussed in section 14) and only the parallel component directly opposing the motion is used in the formula for W. And if F varies in the course of the motion, an appropriate average value must be used in the formula for W.”
Zach, You used the phrase “harness work”. Not a usual semantic expression. The idiom is “harness energy for useful work”. Already, other folks have pointed out that you are conflating energy and work, which are expressed in different units of measure.
You have posted energy values ignoring the fundamental fact that work is a vectored concept. The vector of force is the specified target state and the math treatment is adjusted to this fact. (see above) Energy, as the calories in blocks of wood, is not organized for work output and this energy you report implies the tacit information that a thermal conversion system – like a furnace can be used to achieve a vectored force from their potential energy.
Thermodynamics addresses structure in systems. Woodblocks work when used as a stepping stool. They can organize a system for a short fellow like me – to achieve a target state involved in reaching higher cabinets more productively. It is in this sense that logical arrangement – as negentropy – can change the productive output of a system. (Or at least save me the embarrassment of hopping up and down wasting time and energy)
Static charges in the clouds are a perfect example of high entropy. Lots of energy – but the vectors that would produce work are not organized or arranged in a logical pattern for systemic results. As I pointed out, a bolt of lightening has the ability to be a vectored force. But the organization needed to turn this potential - to actual useful work - is not manifest at this time in technology development. A lightening strike is not work – it’s called damage. That is why we try to convert this vector into a grounded pathway for dissipation. A copper-plated ground rod can be seen to be working (semantically and physically) because it exactly opposes the motion or charge of the detrimental force as a protection system.
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Zachriel
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Member # 1793
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posted 06. June 2006 15:14
Stephen Wright: "The work W performed while overcoming a resisting force F over a distance x is defined as F times x"
Ok so far.
Stephen Wright: "You have posted energy values ignoring the fundamental fact that work is a vectored concept."
You should be specific about such posts. What energy values have I posted.
Stephen Wright: "Woodblocks work when used as a stepping stool."
Hmm. Work = force times distance. Over what distance does a stepping stool work?
Stephen Wright: "A lightening strike is not work – it’s called damage."
That is incorrect. The energy in a lightning bolt does thermodynamic work when electrons travel along its path, when it ionizes molecules of the atmosphere, when it severs a tree trunk, or when it ignites a fire. These are all examples of thermodynamic work.
[ 06. June 2006, 15:16: Message edited by: Zachriel ]
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Zachriel
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Member # 1793
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posted 06. June 2006 15:30
Stephen Wright: "You have posted energy values ignoring the fundamental fact that work is a vectored concept."
Work is not a vectored concept, but like energy and entropy, work is a scalar quantity
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2ndclass
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Member # 1979
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posted 06. June 2006 15:52
quote:
Already, other folks have pointed out that you are conflating energy and work, which are expressed in different units of measure.
No, they aren't. They're both measured in joules, Btu, calories, whatever.
quote:
You have posted energy values ignoring the fundamental fact that work is a vectored concept.
No, it isn't. As the dot product of force and distance, it's a scalar value.
quote:
Energy, as the calories in blocks of wood, is not organized for work output...
Yes, it is. At the very least, a fire will cause the air around it to expand. Whether this expansion is resisted by a piston or by atmospheric pressure, this is work. quote:
A copper-plated ground rod can be seen to be working (semantically and physically) because it exactly opposes the motion or charge of the detrimental force as a protection system.
Lightning rods don't oppose lightning -- they attract it.
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William DeJong
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Member # 1162
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posted 08. June 2006 11:47
2ndclass : You seem to have the mistaken idea that adding energy to a system decreases its entropy. This is entirely false. Entropy always increases with an influx of energy and decreases with an outflux of energy. If the outflux occurs at a lower temperature than the influx, then the system may experience a net decrease in entropy, according to the 2nd Law. posted 06. June 2006 12:58
The 2nd law mathematically formalizes the fundamental property of reality that if the flux of energy over the boundaries of a system is zero, then its entropy (disorder) increases. Over this, misunderstanding is impossible.
The 2nd law relates the flux of energy over the boundaries of a system during an interval [t1, t2] to its entropy S1 on t1 and its entropy S2 on t2. Entropy, however, is not identical with the energy flux over the boundaries of the system, since no "is-equal-sign" is present in the 2nd law but only an "is-smaller-than-sign". As a result, entropy cannot be calculated directly from the measurement of the energy flux over the boundaries of a system, and additional assumptions are necessary to obtain things such as "the standard entropy of a system".
Boltzmann's law S = k ln W (where W is the probability of the state of a system and S its entropy) pictures the entropy of a system as an increasing curve. Since probabilities are restricted to the interval [0,1] it is sufficient to examine S over this interval only. Over [0,1] S is negative. According to Botzmann's law, an entropy S1 = -4 is less probable than an entropy S2= -2. In other words, a decrease of entropy is less probable than an increase of entropy (notice that -4 is smaller than -2). According to Boltzmann's law, the most probable state of a system (that is when W=1) is the state where its entropy is maximal.
The keypoint in the 2nd law is that the entropy (disorder) of a system increases if flux of energy over its boundaries is absent or is absent on average. This is confirmed by empirical evidence:
- In experiment1 (see my post on 03. June 2006 04:44) the energy flux over the boundaries of R is zero during [t1,t2] and the improbable state of seperation of G1-molecules and G2-molecules in the compartements C1 and C2 turns into the most probable state of complete disorder (corresponding with an increase of the entropy of R), according to the 2nd law.
- In experiment2 (see my post on 06. June 2006 07:31) the flux of energy over the boundaries of R is zero on average during [t3,t4] and the state of complete mixture of G1 and G2 does not change into a less probable state of separation of G1 and G2 (what would correspond with a decrease of the entropy), according to the 2nd law. Separation of the gas mixture, movement to a less probable state, and decrease of entropy only happens during interval [t4,t5] when D is switched on.
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