Generalized uncertainty principle and stochastic gravitational wave background spectrum

This paper concerned with the effect of generalized uncertainty principle (GUP) on the stochastic gravitational wave (SGW) background signal that produced during first order cosmological QCD phase transition in early universe. A modified formula of entropy is used to calculate the temporal evolution of temperature of the universe as a function of the Hubble parameter. The pressure that results from the recent lattice calculations, which provides parameterizations of the pressure due to u, d, s quarks and gluons, with trace anomaly is used to describe the equation of state around QCD epoch. A redshift in the peak frequency of SGW at current epoch is calculated. The results indicate an increase in the frequency peak due to GUP effect, which improves the ability to detect it. Taking into account bubble wall collisions (BWC) and turbulent magnetohydrodynamics (MHD) as a source of SGW, a fractional energy density is investigated. It is found that the GUP effect weakens the SGW signal generated during QCD phase transition in comparison to its counterpart in the absence of GUP. These results support understanding the cosmological QCD phase transition and test the effectiveness of the GUP theory. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

This paper examines the impact of the generalized uncertainty principle (GUP) on the stochastic gravitational wave (SGW) background signal in the early universe. By modifying the formula for entropy and using pressure parameterizations based on recent lattice calculations, the temporal evolution of temperature and equation of state around the QCD epoch are studied. The results show that the GUP effect leads to an increase in the frequency peak of SGW and weakens the SGW signal generated during the QCD phase transition.