COSMOLOGICAL CONSTRAINTS ON THE SCALE OF GRAND UNIFICATION

Autor: Graham G. Ross, John D. Barrow
Rok vydání: 2016
Předmět:
Popis: The variation of cosmic baryon number generation with grand unification energy is investigated in a variety of cosmological models. We show that ‘low’ energy unification schemes of the Pati-Salam type will not generate a significant cosmological baryon number in cosmological models consistent with observation. We also evaluate the baryon production by primordial black holes with delta function and power-law number density spectra. A sufficiently steep black hole number spectrun allows ‘low’ energy unification schemes to explain the observed baryon content of the universe and also be in accord with other astronomical limits. The production of stable magnetic monopoles by the Hawking effect is also calculated. In conjunction with observations of the Universe's deceleration this enables the black hole production to be excluded when the unification scale is ‘low’. It also enables very strong limits to be placed on the possible abundance of primordial black holes.
Databáze: OpenAIRE