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Entropy of horizons and particles

  1. Jun 5, 2005 #1
    It seems that the cosmological event horizon has an entropy associated with its surface and which constrains the entropy inside that surface calculated in the same way as the entropy of a BH horizon. And recently we discovered that the universe is accelerating so that the cosmological event horizon is getting smaller. With a shrinking cosmological event horizon comes a decrease in the entropy constraint inside the smaller volume. I wonder if this decrease in cosmological entropy might have an effect to force complexity to arise. Could this be responsible for the creation of life, etc.

    To that end, I wonder could the entropy inside the volume of the cos. event horizon ever be more than that calculated for the surface of the cosmological event horizon? Then a shrinkage of the cosmological event horizon would force the material inside to assume a form which decreases entropy (life?) But it may be that the cosmological event horizon could alway be so much more than what could ever exist inside it that there would be no force on matter states to lower entropy. Some believe that there is a certain amount of entropy associated with each particle, and some believe that space itself has a certain amount of entropy. So, in order to resolve these questions, I imagine that the expansion of the universe accelerates so much that the cosmological event horizon approaches to zero. How would the empty space inside respond?.

    If there were no particles inside this shrinking cosmological event horizon, and space itself had no entropy, then there would be zero entropy inside. I suppose that the cosmological event horizon could shrink to zero in this state without having any effects. But I hear, however, that curved space may have some entropy associated with it. Then the universe could not expand any faster than it uncurls. Is it possible for the universe then to expand fast enough so the that a shrinking cosmological event horizon could entrap the entropy of some uncurling space? What would be the result, would that be to create particles as a store of information as an entropy reducing process? It does seem that shrinking event horizons to create particles in the case of black holes. I wonder if this is not the process that created the original particles during inflation when space expanded very fast and particles appeared on the scene. If particles have structure, then isn't structure a type of signal that contains information? I hear some string theorist say that strings do contain information as part of their structure. Can we then calculate the entropy of particles without knowing what their exact nature is? What are the smallest particles given off as the smallest black hole evaporates to nothing? And what is the entropy calculated for this smallest black hole?

    OK, suppose now that particles have entropy, what is the minimum cosmological horizon that can exist given the density of the universe before any further shrinkage will start to cause material to congeal and form additional structures. Is this the same as gravity? Some think gravity itself has entropy associated with it. I think not since then an increasing cosmological horizon would be anti-gravity, which we don't see when the universe was decelerating.

    One of the questions that has to be answered along these lines is whether entropy is something that travels faster than light. If the cosmological event horizon shrinks a given amount, does this have immediate effects, or does that information take time to work its way throughout the system? I understand entropy to be an equation describing the whole state of a system no matter how its particles are distributed and no matter how they are moving. So then any change in an entropy constraint must have immediate effects throughout the system. It seems curious that the universe started accelerating about the same time that life appeared on earth. Is that a coincidence? Or is this the creation principle?
    Last edited: Jun 5, 2005
  2. jcsd
  3. Jun 7, 2005 #2
    Entropy, horizons, particles, and life.

    I suppose we can consider a particle with mass, m, to be a black hole of mass, m, find the surface area of a black hole of mass, m, and calculate the entropy of that size of a black hole, right? That would be the information content of that particle, right? But the faster a particle travels the more mass it has, and the more information/entropy it has. So is information/entropy a relative thing?

    The next question would be: what is the average entropy/information density of the universe. To answer this we need to know how much information/entropy is contained galaxies. Matter is not evenly distributed throughout the universe but is clumped into galaxies. Perhaps the information content of a galaxies is proportional to the volume of the universe divided by the volume occupied by galaxies. What do ya think?
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