Abstract
From the point of view of the gauge hierarchy problem, introducing an intermediate scale in addition to TeV scale and the Planck scale (MPl=2.4×1018 GeV) is unfavorable. In that way, a gauge coupling unification (GCU) is expected to be realized at MPl. We explore possibilities of GCU at MPl by adding a few extra particles with TeV scale mass into the standard model (SM). When extra particles are fermions and scalars (only fermions) with the same mass, the GCU at MPl can (not) be realized. On the other hand, when extra fermions have different masses, the GCU can be realized around 8πMPl without extra scalars. This simple SM extension has two advantages that a vacuum becomes stable up to MPl (8πMPl) and a proton lifetime becomes much longer than an experimental bound.
Highlights
The collider experiments have discovered all particles in the standard model (SM), and properties of the SM particles are gradually revealed
Masses of the Higgs boson and top quark are important to investigate a behavior of the quartic coupling of the Higgs boson at a high energy scale
We have explored possibilities of gauge coupling unification (GCU) at the Planck scale in the extended SM which includes extra particles around the TeV scale
Summary
The collider experiments have discovered all particles in the standard model (SM), and properties of the SM particles are gradually revealed. We try to realize the gauge coupling unification (GCU) at the Planck scale by introducing additional particles in the TeV scale. It is known that the GCU could be realized due to the asymptotic safety of gravity, in which all gauge couplings rapidly become zero and approach the same value around the Planck scale In this scenario, the gravitational contributions have been calculated at lowest nontrivial order in perturbation theory [25]. We assume that the Higgs mass term is generated by Coleman-Weinberg mechanism and it does not cause the hierarchy problem In this background, we will consider the GCU at the Planck scale to avoid the introduction of any intermediate scales except for the TeV scale.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
