ENTROPY AND ANTI ENTROPY The scientific definitions of entropy can be difficult, and are mostly involved with the tendency of concentrations of energy to flow out to even concentrations everywhere. A more useful definition of entropy is a measure of the uselessness of energy to a given purpose, because in the end energy can neither be created or destroyed. For example a hungry man needs energy to stay alive. If you give him a battery, which has energy in it, he won't be able to utilize it because he can't eat it. Thus the battery has high entropy relative to the needs of the user, even though it has a high concentration of energy. It is a USELESS concentration of energy to that particular need. On the other hand if you give bread to a man lost in a dark cave whose flashlight has gone dim, again the bread will do him little good because he needs the battery! As energy is expended in one form, like the battery burning the light bulb, it tends to expand out into another form, like light racing across the universe. That light is still energy, but it is of no further use to the original user of the battery once it is gone. Unless of course he is signalling mars with his flash light! But once it hits Hars, the light gets absorbed as heat and is no more, again it becomes useless to anyone unless one is trying to heat mars. You see how it goes, in many ways entropy is the state of energy in relation to its usefullness to a particular purpose. Now it is tempting to say that there is none the less an absolute state of entropy, a state where energy is useless to everyone, meaning no longer capable of transforming into any other kind of energy (which is all that usefullness is), and thus everything eventually becomes an unchanging state. But one has to remember that energy comes in two forms, potential and kinetic. The battery is potential, the light is kinetic. The Sun is a source of kinetic energy which hits random carbon dioxide moecules on EARTH splitting them up. You start with some photons and CO2, and you end up with no photons and Carbon and Oxygen. Is that a higher state of entropy? Well relative to the sun yes, but relative to an animal no. Although highly simplified here, the carbon forms plants and trees, and act as a storage battery for the light from the suns. Plants are the battery in a state of charge. Animals would much prefer that a plant cell trap a photon, than a rock where the light is 'lost' to heat. But the heat keeps the plant warm, and alive, for if it gets too cold, the plant won't live. The animal eats the plant using up the charge in the battery, and turns it into muscle power which it uses to plant more plants or build silos for plants, or tranportation systems for plants, a civilization in other words. Thus we have a small eddy of anti entropy that takes photons from the sun, stores them as plants, gets eaten as animals which do useful work (relative to them) to build civilizations. THEN the photon escapes as heat into space never to be useful again :). Until it hits Mars and helps them grow plants too (in the future). So the flow of energy from high concentrations (anti entropy) to low dispersed uselessness is not a simple path, and what happens along the way is everything we call life. Life is the death throes of energy heading for entropy. In this model life is swirls in a river where things go around and round, but eventually EVERYTHING gets swept out to sea (final entropy). But in all this we need to remember that what started out as kinetic energy from the sun, ends up as potential energy, first in the carbon of the plants, and finally as background cosmic radiation. Take a ball and throw it up in the air, when it reaches it's top it no longer has an kinetic energy, but all the energy is still there as potential energy. Some was lost to friction in the air as heat and it is gone to the great dispersement in the sky, or off to heat Mars. But the rest is recoverable as the ball falls back down and hits your hand as fast as you sent it up, almost. So the entire universe is expanding and thus storing all of its expended energy as gravitational potential energy. This might be useless to any thing in that universe near the end when things are at maximum expansion, and maximum dispersement, but the energy is all still there! *IF* the universe turns around and starts to collapse under its own gravitational field, just like the ball turning around and dropping, then all that dispersed energy gets concentrated again until the universe either crashes into itself at an infinite point or passes by itself, or through itself at a very small point and starts another expansion cycle. At that point all the potential energy is now again kinetic. If the universe never turns around and just keeps expanding forever because its original impetus had escape velocity, or because new energy is being pumped into the system, then entropy will grow forever, but the energy is never lost. Because there is nothing saying that a universe must fundamentally expand forever, entropy then is only king while its in the lime light, for in a universe that does contract, like the ball falls once thrown in the air, anti entropy becomes king during the reverse process. Homer ------------------------------------------------------------------------ Homer Wilson Smith The Paths of Lovers Art Matrix - Lightlink (607) 277-0959 KC2ITF Cross Internet Access, Ithaca NY homer@lightlink.com In the Line of Duty http://www.lightlink.com Sun May 13 00:05:46 EDT 2007