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Ah, Ed, so today we are not going to divert this thread into a discussion of Hitler, gay sex, or the cause of the Big Bang. Today's topic is the thermodynamics of planets. Well, uh, OK then.
source: Entropy production - Wikipedia
(edit: it appears I cannot copy this formula here. If you want to see the formula, click on the link and look at the first formula under the heading First and Second Law.)
This tells us that there are 3 things that can change the entropy of a system, such as planet earth: heat transfer, mass transfer, and internal processes.
The middle term relates to mass transfer. This is basically zero for planet earth. So we can ignore it. We are left with the first term (heat transfer to and from the earth) and the third term (internal processes on earth). You are correct that the net result of the third term always increases the entropy of earth. But the first term can be either positive or negative depending on the dynamics of the heat flow. For earth, the first term is negative, and tends to balance out the last term which is positive.
Is there a net change of the entropy of earth? For most of the earth's history, the earth has been in steady state and at a near constant entropy. However, the addition of carbon dioxide to the earth's atmosphere has reduced the efficiency at which the earth radiates heat to space. Because of this, the first term of the equation is not radiating heat and decreasing entropy as fast as it used to. The earth is getting warmer. As the earth warms, the thermodynamic entropy increases. For instance, if ocean water evaporates at 70 deg F, the entropy (S) changes from 0.0745 to 1.7566 BTU/lbm, which is a huge increase in entropy. Were the oceans all to evaporate, earth would become one hot mess of high entropy steam with no life. But we digress.
My point was not that the net entropy of the planet decreases, but that the flow of heat into and out of the planet causes decreases in entropy (first term of our equation). However, the last term of our equation degrades this low entropy source to high entropy waste. But in the process, some of that low entropy material can be converted to other low entropy materials that humans consider organized. That is allowed by the second law. As long as the internal processes are causing a net increase of the planet's entropy, some parts of the process are allowed to decrease in entropy. Examples of low entropy products made this way include diamonds, petroleum, glaciers, snowflakes, and trees. All these processes proceed naturally on planet earth and need no intervention of a mind to cause them to happen. Although these objects are low in entropy, they happen because the first term in our equation lowers the net entropy of the earth, and because there are natural mechanisms to do the transformations.
Notice that nowhere in the equation is the presence of a mind postulated. No mind is needed to drive the processes. And no mind can violate the second law. But if a mind finds a mechanism that can use a low entropy source to create other low entropy materials, that is allowed, as long as the net result including the generated waste is a net increase in entropy.
So, no the laws of thermodynamics do not prove that minds must be lowering entropy. And no, minds cannot even lower entropy in violation of the equation above.
So anyway, that is our lessen in thermodynamics for today. Class is dismissed.
That is not my claim, but for the record, here is the formula for the change in entropy of a system such as planet earth:No, the specific reference that states and explains how the earth has a constant overall reduction of entropy.
source: Entropy production - Wikipedia
(edit: it appears I cannot copy this formula here. If you want to see the formula, click on the link and look at the first formula under the heading First and Second Law.)
This tells us that there are 3 things that can change the entropy of a system, such as planet earth: heat transfer, mass transfer, and internal processes.
The middle term relates to mass transfer. This is basically zero for planet earth. So we can ignore it. We are left with the first term (heat transfer to and from the earth) and the third term (internal processes on earth). You are correct that the net result of the third term always increases the entropy of earth. But the first term can be either positive or negative depending on the dynamics of the heat flow. For earth, the first term is negative, and tends to balance out the last term which is positive.
Is there a net change of the entropy of earth? For most of the earth's history, the earth has been in steady state and at a near constant entropy. However, the addition of carbon dioxide to the earth's atmosphere has reduced the efficiency at which the earth radiates heat to space. Because of this, the first term of the equation is not radiating heat and decreasing entropy as fast as it used to. The earth is getting warmer. As the earth warms, the thermodynamic entropy increases. For instance, if ocean water evaporates at 70 deg F, the entropy (S) changes from 0.0745 to 1.7566 BTU/lbm, which is a huge increase in entropy. Were the oceans all to evaporate, earth would become one hot mess of high entropy steam with no life. But we digress.
My point was not that the net entropy of the planet decreases, but that the flow of heat into and out of the planet causes decreases in entropy (first term of our equation). However, the last term of our equation degrades this low entropy source to high entropy waste. But in the process, some of that low entropy material can be converted to other low entropy materials that humans consider organized. That is allowed by the second law. As long as the internal processes are causing a net increase of the planet's entropy, some parts of the process are allowed to decrease in entropy. Examples of low entropy products made this way include diamonds, petroleum, glaciers, snowflakes, and trees. All these processes proceed naturally on planet earth and need no intervention of a mind to cause them to happen. Although these objects are low in entropy, they happen because the first term in our equation lowers the net entropy of the earth, and because there are natural mechanisms to do the transformations.
Notice that nowhere in the equation is the presence of a mind postulated. No mind is needed to drive the processes. And no mind can violate the second law. But if a mind finds a mechanism that can use a low entropy source to create other low entropy materials, that is allowed, as long as the net result including the generated waste is a net increase in entropy.
So, no the laws of thermodynamics do not prove that minds must be lowering entropy. And no, minds cannot even lower entropy in violation of the equation above.
So anyway, that is our lessen in thermodynamics for today. Class is dismissed.
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