Planck scale effects on the stochastic gravitational wave background generated from cosmological hadronization transition: A qualitative study

We reconsider the stochastic gravitational wave background spectrum produced during the first order hadronization process, in presence of ultraviolet cutoffs suggested by the generalized uncertainty principle as a promising signature towards the Planck scale physics. Unlike common perception that the dynamics of QCD phase transition and its phenomenological consequences are highly influenced by the critical temperature, we find that the underlying Planck scale modifications can affect the stochastic gravitational spectrum arising from the QCD transition without a noteworthy change in the relevant critical temperature. Our investigation shows that incorporating the natural cutoffs into MIT bag equation of state and background evolution leads to a growth in the stochastic gravitational power spectrum, while the relevant redshift of the QCD era, remains unaltered. These results have double implications from the point of view of phenomenology. Firstly, it is expected to enhance the chance of detecting the stochastic gravitational signal created by such a transition in future observations. Secondly, it gives a hint on the decoding from the dynamics of QCD phase transition. (C) 2018 The Authors. Published by Elsevier B.V.