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Is observation an anentropic process?

  1. Sep 9, 2004 #1
    Interaction between biota and their environment more often increases the order of the former (memory, DNA, morphological adaptation) and the latter's randomness. Observation is greatly affected by whether or not entities observed are recognizable, and thus incorporable. The maintenance of homeostasis is a basic example of how an organism emulates a self-organizing system.

    While exploring their environment, beings probe, both utilizing illumination and perpetuating the anentropic structure - the physical self - that is the objective of life. The individual observer stands as the constant in determining the scale on which entropy is to be considered. Personal order allows a standard upon which disorder can be measured.

    Would you agree that observation is an anentropic process?
  2. jcsd
  3. Sep 10, 2004 #2


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    Life does not conflict with the second law of thermodynamics. Life creates order, but requires energy to do so. The ultimate source of most forms of energy for human beings can be traced back, directly or indirectly, to our sun, orenergy that came at one time from our sun (in rare instances, other suns), and was stored.

    So without the existence of our Sun / other suns, life would not be possible. From the point of view of thermodynamics, life is a little bit like an eddy current that moves upstream. When you crunch the numbers, you find that the eddy current which flows for a little bit upstream does not upset the laws of physics that say that water flows downhill. Neither is life in conflict with the laws of thermodynamics.

    As far as quantum mechanics goes it would be fairly traditional (I think) to say that the act of observation creates entropy. Certainly, when you have a reversible operation, you do not have a change in entropy. So, if you pass a beam of light through a calcite polarizer, and separate out the photons with |up> polarization from those that have a |down> polarization, you have not yet conducted a measurement. With enough precision, you can put the light beam back through an identical piece of calcite, and "undo" the whole process.

    The act of measurment requires an "irreversible" step, one that can't be reversed, like actually allowing the photons to hit a detector, and allowing the detector to interact with the environment.

    The really interesting thing is that since the evolution of the wavefunction is purely unitary, it's a bit of a puzzlement how "irreversible" things happen. The laws of physics run just as well in reverse as forwards, and quantum mechanics is not an exception to this. But we know that on a macroscale that when you drop an egg it splatters, if you reverse the film, the direction of time can be clearly distinguished. The origin of the "arrow of time" is, I believe, still a matter for much philosophical debate, but unfortunately it doesn't seem to be a very productive phenomenon to study experimentally, and winds up having the capability to absorb an enormous amount of time and effort without a lot to show for it.
  4. Sep 10, 2004 #3


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    I would say not. The entropy of the energy expended to make an observation exceeds the negentropy of the information obtained.
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