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Feedback and Control Theory applied to Cosmology and Particle Physics

  1. Nov 10, 2013 #1
    The radical Smolin thread left me wondering if other similar ideas could not be applied to other areas of Cosmology and even Particle Physics.

    Every complex system I can think of in our lives, and in nature, forms part of a complex multifaceted control system or process, with various feedback setpoints and equilibrium points, interactions and inter dependencies.

    Many people continue to wonder how the laws of Physics, the particle zoo, inflation, dark energy, dark matter, galaxy and galaxy cluster evolution etc all evolved and ended up the way they did and continue to this day, many in perfect equilibrium, some apparently still continuing to evolve eg. dark energy.

    Has anybody considered applying evolution models and systems theory to help explain how the Universe and its laws ended up the way they did? Perhaps One of the simplest examples I can think of is the well known, but very important, strong force equilibrium model which explains why atomic nuclei are the way they are :

    http://www.cartage.org.lb/en/themes/Sciences/Physics/NuclearPhysics/WhatisNuclear/Forces/Forces.htm [Broken]

    I wonder how many other similar models there are for other parts of parts of Physics? And whether some form of very early on evolution or interaction could have played a roll in determining each of their contributions?
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Nov 11, 2013 #2


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    One significant issue is that any description of how the physical laws change must also explain why they have remained remarkably stable within the observable universe. I think this is the primary reason why most discussions of how the low-energy laws of physics can change rely upon phase transitions.

    P.S. I don't know why you put dark energy in there, as there is no indication that it is changing at all.
  4. Nov 12, 2013 #3


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    Would not changes in physical laws be evident in ancient light from distant galaxies?
  5. Nov 16, 2013 #4
    When I wrote the above I think I was feeling inspired. Now I am not so sure why, but here goes...

    I think there are patterns in nature from the smallest particles to the largest galaxy clusters and they all seem to share one thing in common and that is positions of equilibrium. The key is understanding what is working to maintain equilibrium on each scale or size. We have things like the strong force at the very smallest scales. We have gravity and momentum maintaining equilibrium at planetary orbit scales.

    Now in Cosmology we need to discover what is maintaining equilibrium of star rotation in a galaxy. We call this dark matter but we still dont know what that is. We also may not be sure what is maintaining the equilbrium in the distribution of galaxy voids, galaxy clusters and galaxy threads, at even larger scales, I am not sure if we know this or not.

    Finally and importantly we are also not sure what is missing to prevent an unlimited accelerating expansion of the Universe. If we can find a point equilibrium at all other scales perhaps we will ultimately find one here also, but for this we have to discover what is behind all the components of what we call dark energy which could be capable of creating a point of equilibrium at scales as large as the observable universe.

    That is the equilibrium part of the question, now on to the evolution of the laws of Physics and forces of nature that govern our Universe today.

    When the Universe began from an extremely small point of high energy would not the laws of Physics and forces of nature been very different to the way they are today? For example at such high energies I think we have Grand Unified field theories? If so would these forces and laws of nature have not have evolved in a very short time, although not instantaneously, from this more simple state to the laws of Physics and forces of nature that we now have today? So I was suggesting that perhaps some form of evolution model with feedback, moving points of equilibrium and complex dependencies could have been in play during this short time when the various forces were emerging. This process would have determined what type of Universe, laws of Physics and forces of nature we ultimately ended up with today.

    It is interesting to note that on the smallest particle scales the Universe found final points of equilibrium very quickly indeed, but on scales the size of the Observable Universe we are apparently still waiting for a possible point of equilibrium to be achieved. Is the Universe expanding and accelerating completely out of control until everything flies apart or is this expansion temporary and part of a more complex process involving maintaining another point of equilbrium elsewhere, perhaps relating to the size and distribution of matter in galaxy superclusters? If so what feedback mechanism could be taking place to do this? Are there additional forces of nature which need to be introduced at scales the size of Galaxies and scales the size of the Observable Universe and which may have appeared later on than the first four forces that we already know about?

    The Universe appears to me to be one very long, very complex process and sequence of events converting high initial energy into ever increasing complexity at ever increasing scales. Could the Universe have inherited something equivalent to genes to determine how all this took place? I think this may be Smolin's hypothesis, I am not sure. Would this then qualify the Universe as a form of life? Some kind of Universal Gaia principle? Regardless I think there is still a great deal of large scale structure and change in its large scale structure that we still cant explain, starting from features the size of a galaxy and its spin rates and on upwards to beyond the size of the Observable Universe and this structure still appears to be growing in size and also increasing in complexity at the largest scales. In effect it is therefore still a child Universe and we will never be able to see the whole of it or its higher levels of complexity.
    Last edited: Nov 16, 2013
  6. Nov 17, 2013 #5

    George Jones

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    I have closed this thread, as Physics Forums rules prohibit the discussion of personal theory.
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