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Possibilities for a 5th force?

  1. Jul 15, 2014 #1
    It is quite accepted that at sufficiently high energies 3 of the known 4 forces merge into 1 fundamental force, and it is expected by many that at even higher energies gravity should also merge with them into a single primordial force. We find ourselves in an energy period of the universe where the primordial superforce has split into 4 by different symmetry breaks.

    But taking the other way, towards the future and even lower energies than current, has anybody ever speculated that a new symmetry breaking could occur creating a lower energy 5th force? Why should the splitting stop at 4?
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  3. Jul 15, 2014 #2


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  4. Jul 15, 2014 #3
    Thanks those are nice. My question though was rather not so much whether we currently have a yet undetected 5th force (which is surely interesting enough) but whether we may just have 4 forces now but with further dilution of the energy in the future a new symmetry breaking could take place giving rise to a not-yet existing force.
  5. Jul 15, 2014 #4


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    I don't know if anyone is specifically looking for a fifth force. However many lab experiments take place at temperatures close to absolute zero, so I suspect there is no such force.
  6. Jul 15, 2014 #5


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    You could make a case for dark energy as a fifth force. Scientists are fairly convinced it exists, but, have little clue what it is, how it interacts, or its mediating particle. Not that we know all that much more about gravity. The graviton is the hypothetical mediating particle for gravity, but, has never been experimentally detected.
  7. Jul 15, 2014 #6


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    Not my specialist subject, but it seems strange that string theorists can only postulate of one more force. Can't they come up with an reason why there should be at least 37? :smile:
  8. Jul 17, 2014 #7
    Last edited by a moderator: May 6, 2017
  9. Jul 18, 2014 #8
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