10 papers
Radiative Breaking of Two-Zero Neutrino Mass Minors: Revisiting the Model
Masahiro Ibe, Jun Miyamoto, Satoshi Shirai
The two-zero minor structure predicted by flavor symmetries is usually discussed as a tree-level relation among low-energy neutrino parameters. We point out that this relation can…
Fermion Multiplicities at the GUT Scale: A Statistical Study of Unification and Proton Decay
Akifumi Chitose, Ko Hirooka, Masahiro Ibe +1
We study the impact of multiple vector-like fermions in SU(5) grand unified theory (GUT). Threshold effects from extra fermions allow the observed gauge couplings to be consistentl…
A Closer Look at Constrained Instantons
Takafumi Aoki, Masahiro Ibe, Satoshi Shirai
Instantons play a crucial role in understanding non-perturbative dynamics in quantum field theories, including those with spontaneously broken gauge symmetries. In the broken phase…
Flavor Symmetry and Proton Decay in PeV-Scale Supersymmetry
Akifumi Chitose, Masahiro Ibe, Satoshi Shirai
Supersymmetry beyond the TeV scale offers several theoretical and phenomenological advantages, such as accommodating the observed Higgs mass and alleviating the flavor and CP probl…
Do Cosmic String Segments Emit Gravitational Waves?
Akifumi Chitose, Masahiro Ibe, Shunsuke Neda +1
Cosmic strings are predicted in various extensions of the Standard Model, including grand unified theories. Depending on the symmetry-breaking pattern, they can be either topologic…
Cosmic Strings in Multi-Step Symmetry Breaking
Akifumi Chitose, Masahiro Ibe, Satoshi Shirai +1
We investigate cosmic strings arising from a hierarchical gauge symmetry breaking sequence, $\mathrm{SU}(2) \times \mathrm{U}(1) \rightarrow \mathrm{U}(1) \times \mathrm{U}(1) \rig…