Grand Unification and Cosmology

  • John Ellis
  • Mary K. Gaillard
  • D. V. Nanopoulos
Part of the Ettore Majorana International Science Series book series (EMISS, volume 7)


Do cosmology and grand unified theories (GUTs) of elementary particle interactions have anything useful to say to each other? There is a great deal of theoretical work on GUTs unifying the strong, weak and electromagnetic interactions1, now that many theorists perceive these individual interactions to be understood in principle. GUTs invoke energy scales of O(1015) GeV which seem vertiginous to many physicists. It is not imaginable to reach these energies in laboratory experiments, and experimentalists are therefore forced to look for very indirect and feeble side-effects of grand unification such as proton decay. Even these valiant efforts may be brought to nought by a (logarithmically) modest increase in the grand unification mass-scale2. However, this mass-scale may be achieved directly in cosmological and astrophysical situations. For example, black hole explosions could in principle achieve temperatures up to the Planck temperature of 1032°K corresponding to energies of 1019 GeV, while temperatures corresponding to particle energies of 1015 GeV or more are generally thought to have occurred very early in the Big Bang when the Universe was about 10−37 seconds old.


Higgs Boson Yukawa Coupling Neutrino Masse Vector Boson Baryon Number 
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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • John Ellis
    • 1
  • Mary K. Gaillard
    • 2
  • D. V. Nanopoulos
    • 1
  1. 1.CERNGenevaSwitzerland
  2. 2.LAPPAnnecy-le-VieuxFrance

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