A solution to the electroweak horizon problem in the R_mathrm{h}=ct universe

Fulvio Melia

doi:10.1140/epjc/s10052-018-6231-0

Abstract

Particle physics suggests that the Universe may have undergone several phase transitions, including the well-known inflationary event associated with the separation of the strong and electroweak forces in grand unified theories. The accelerated cosmic expansion during this transition, at cosmic time tsim 10^{-36}-10^{-33} s, is often viewed as an explanation for the uniformity of the CMB temperature, T, which would otherwise have required inexplicable initial conditions. With the discovery of the Higgs particle, it is now quite likely that the Universe underwent another (electroweak) phase transition, at T=159.5pm 1.5 GeV – roughly sim 10^{-11} s after the big bang. During this event, the fermions gained mass and the electric force separated from the weak force. There is currently no established explanation, however, for the apparent uniformity of the vacuum expectation value of the Higgs field which, like the uniformity in T, gives rise to its own horizon problem in standard varLambda CDM cosmology. We show in this paper that a solution to the electroweak horizon problem may be found in the choice of cosmological model, and demonstrate that this issue does not exist in the alternative Friedmann–Robertson–Walker cosmology known as the R_mathrm{h}=ct universe.

Highlights

Several phase transitions in particle physics have potentially deep implications for cosmology
As the Universe cooled down further following the electroweak phase transition (EWPT), a third phase transition is believed to have occurred at roughly 100 MeV, corresponding to a time t ∼ 10−6 s in ΛCDM
We suggest that the electroweak horizon problem (EHP) may be due to an incorrect choice of the cosmology, and propose that the solution may be found – not in a tweaked ΛCDM but, rather – in the alternative Friedmann-Robertson-Walker (FRW) cosmology known as the Rh = ct Universe [21–24]

Summary

Introduction

Several phase transitions in particle physics have potentially deep implications for cosmology. As the Universe cooled down further following the EWPT, a third phase transition is believed to have occurred at roughly 100 MeV, corresponding to a time t ∼ 10−6 s in ΛCDM This would have arisen out of quantum chromodynamics, associated with the transformation of quarks behaving like free particles (in a quark-gluon plasma at asymptotically high temperatures) into the ‘confined states’ of baryons and mesons in the hadronic phase as the Universe continued to expand. Zeldovic et al [10] and Kibble [11] offered an early assessment of the possibility that domain walls might have been created in the cosmos as a result of such scale transitions in the early Universe These topological defects would have significant observational consequences, e.g., producing measurable anisotropies in the CMB temperature [12–14].

Background

The electroweak horizon problem

Conclusion