The second law is a straightforward law of physics with the consequence that, in a closed system, you can't finish any real physical process with as much useful energy as you had to start with — some is always wasted. This means that a perpetual motion machine is impossible. The second law was formulated after nineteenth century engineers noticed that heat cannot pass from a colder body to a warmer body by itself.
Thermodynamic Entropy
The first opportunity for confusion arises when we introduce the term entropy into the mix. Clausius invented the term in 1865. He had noticed that a certain ratio was constant in reversible, or ideal, heat cycles. The ratio was heat exchanged to absolute temperature. Clausius decided that the conserved ratio must correspond to a real, physical quantity, and he named it "entropy".
Today, it is customary to use the term entropy to state the second law: Entropy in a closed system can never decrease. As long as entropy is defined as unavailable energy, the paraphrasing just given of the second law is equivalent to the earlier ones above. In a closed system, available energy can never increase, so (because energy is conserved) its complement, entropy, can never decrease.
Logical Entropy
Entropy is also used to mean disorganization or disorder. J. Willard Gibbs, the nineteenth century American theoretical physicist, called it "mixedupness." The American Heritage Dictionary gives as the second definition of entropy, "a measure of disorder or randomness in a closed system." Again, it's a negative concept, this time the opposite of organization or order. The term came to have this second meaning thanks to the great Austrian physicist Ludwig Boltzmann.
Richard Feynman knew there is a difference between the two meanings of entropy. Suppose we divide the space into little volume elements. If we have black and white molecules, how many ways could we distribute them among the volume elements so that white is on one side and black is on the other? On the other hand, how many ways could we distribute them with no restriction on which goes where? Clearly, there are many more ways to arrange them in the latter case. We measure "disorder" by the number of ways that the insides can be arranged, so that from the outside it looks the same. The logarithm of that number of ways is the entropy. The number of ways in the separated case is less, so the entropy is less, or the "disorder" is less.
The first opportunity for confusion arises when we introduce the term entropy into the mix. Clausius invented the term in 1865. He had noticed that a certain ratio was constant in reversible, or ideal, heat cycles. The ratio was heat exchanged to absolute temperature. Clausius decided that the conserved ratio must correspond to a real, physical quantity, and he named it "entropy".
Today, it is customary to use the term entropy to state the second law: Entropy in a closed system can never decrease. As long as entropy is defined as unavailable energy, the paraphrasing just given of the second law is equivalent to the earlier ones above. In a closed system, available energy can never increase, so (because energy is conserved) its complement, entropy, can never decrease.
Logical Entropy
Entropy is also used to mean disorganization or disorder. J. Willard Gibbs, the nineteenth century American theoretical physicist, called it "mixedupness." The American Heritage Dictionary gives as the second definition of entropy, "a measure of disorder or randomness in a closed system." Again, it's a negative concept, this time the opposite of organization or order. The term came to have this second meaning thanks to the great Austrian physicist Ludwig Boltzmann.
Richard Feynman knew there is a difference between the two meanings of entropy. Suppose we divide the space into little volume elements. If we have black and white molecules, how many ways could we distribute them among the volume elements so that white is on one side and black is on the other? On the other hand, how many ways could we distribute them with no restriction on which goes where? Clearly, there are many more ways to arrange them in the latter case. We measure "disorder" by the number of ways that the insides can be arranged, so that from the outside it looks the same. The logarithm of that number of ways is the entropy. The number of ways in the separated case is less, so the entropy is less, or the "disorder" is less.
Life is Organization
Seen in retrospect, evolution as a whole doubtless had a general direction, from simple to complex, from dependence on to relative independence of the environment, to greater and greater autonomy of individuals, greater and greater development of sense organs and nervous systems conveying and processing information about the state of the organism's surroundings, and finally greater and greater consciousness. You can call this direction progress or by some other name. — Theodosius Dobzhansky
Conclusion
In my opinion, the audacious attempt to reveal the formal equivalence of the ideas of biological organization and thermodynamic order ...must be judged to have failed. — Peter Medawar
Conclusion
In my opinion, the audacious attempt to reveal the formal equivalence of the ideas of biological organization and thermodynamic order ...must be judged to have failed. — Peter Medawar
Computer scientist Rolf Landauer wrote an article published in June, 1996, which contains insight that should discourage attempts to physically link the two kinds of entropy. He demonstrates that "there is no unavoidable minimal energy requirement per transmitted bit". Using Boltzmann's constant to tie together thermodynamic entropy and logical entropy is thus shown to be without basis. One may rightly object that the minimal energy requirement per bit of information is unrelated to logical entropy. But this supposed requirement was the keystone of modern arguments connecting the two concepts.It is surprising that mixing entropy and biology still fosters confusion. The relevant concepts from physics pertaining to the second law of thermodynamics are at least 100 years old. The confusion can be eradicated if we distinguish thermodynamic from logical entropy, and admit that Earth's biological system is open to organizing input from outside.
Read more: http://www.panspermia.org/seconlaw.htm
Read more: http://www.panspermia.org/seconlaw.htm
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