分类: 物理学 >> 核物理学 提交时间: 2016-09-14
摘要: It is of great interest to connect cosmology in the early universe to the Standard Model of particle physics. In this paper, we try to construct a bounce inflation model with the standard model Higgs boson, where the one loop correction is taken into account in the effective potential of Higgs field. In this model, a Galileon term has been introduced to eliminate the ghost mode when bounce happens. Moreover, due to the fact that the Fermion loop correction can make part of the Higgs potential negative, one naturally obtains a large equation of state(EoS) parameter in the contracting phase, which can eliminate the anisotropy problem. After the bounce, the model can drive the universe into the standard higgs inflation phase, which can generate nearly scale-invariant power spectrum.
分类: 物理学 >> 核物理学 提交时间: 2016-09-14
摘要: The observed value of the Higgs mass indicates an instability of the Higgs scalar at large energy scales, and hence also at large field values. In the context of early universe cosmology, this is often considered to lead to problems. Here we point out that we can use the instability of the Higgs field to generate an Ekpyrotic phase of contraction. In the context of string theory it is possible that at very high energy densities extra states become massless, leading to an S-brane which leads to the transition between a contracting phase in the past and the current expanding phase. Thus, the Higgs field can be used to generate a non-singular bouncing cosmology in which the anisotropy problem of usual bouncing scenarios is mitigated.
分类: 物理学 >> 核物理学 提交时间: 2016-08-30
摘要: In this letter, we explore the nature of the electroweak phase transition (EWPT) with both particle colliders and gravitational wave (GW) detection. With the observed Higgs mass, the shape of the Higgs potential is fully determined within the standard model (SM) of particle physics. However, it could be changed if there exists new physics beyond the SM. Working with the effective field theory, we show that a modified Higgs potential with a sextic term included can keep the observed 125 GeV Higgs mass but behave different when compared with the SM case. Furthermore, this potential can produce a strong first order phase transition (SFOPT) for the electroweak baryogenesis and interestingly predict new phenomena in the Higgs sector, which can be tested at colliders such as the Large Hadron Collider (LHC) and the planning Circular Electron Positron Collider (CEPC). We point out this SFOPT can lead to detectable signals for the GW interferometers , such as eLISA, DECIGO and BBO. Our present study on the EWPT bridges the particle physics at colliders with the astrophysics and cosmology in the early universe.