88 citations · 263 across the 14 of their papers we have counts for
15 papers
Stringy Constraints on Modular Flavor Models
Keiya Ishiguro, Takafumi Kai, Tatsuo Kobayashi +1
We investigate stringy constraints on moduli spaces in modular flavor models by analyzing moduli-dependent threshold corrections in heterotic string vacua. While moduli play a cruc…
Classification of Modular Symmetries in Type IIB Flux Landscape
Keiya Ishiguro, Takafumi Kai, Tatsuo Kobayashi +2
In this work, we study modular symmetries in type IIB flux landscape by investigating symplectic basis transformations of period vectors on toroidal orbifolds. To fix explicit cycl…
Stabilization of a twisted modulus on a mirror of rigid Calabi-Yau manifold
Keiya Ishiguro, Takafumi Kai, Hajime Otsuka
We study the stabilization of a twisted modulus in Type IIB flux compactifications on a mirror of the rigid Calabi-Yau threefold. By analyzing the effective action of twisted and u…
Modular forms and hierarchical Yukawa couplings in heterotic Calabi-Yau compactifications
Keiya Ishiguro, Tatsuo Kobayashi, Satsuki Nishimura +1
We study the modular symmetry in heterotic string theory on Calabi-Yau threefolds. In particular, we examine whether moduli-dependent holomorphic Yukawa couplings are described by…
Autoencoder-Driven Clustering of Intersecting D-brane Models via Tadpole Charge
Keiya Ishiguro, Satsuki Nishimura, Hajime Otsuka
We study the well-known type IIA intersecting D-brane models on the orientifold via a machine-learning approach. We apply several autoenco…
Flux Landscape with Enhanced Symmetry Not on Elliptic Points
Keiya Ishiguro, Takafumi Kai, Tatsuo Kobayashi +1
We study structures of solutions for SUSY Minkowski F-term equations on two toroidal orientifolds with . Following our previous study \cite{Ishiguro:2020tmo}, with fi…
Novel moduli space in modular flavor models : a case study for modular seesaw model with hidden gauge symmetry
Keiya Ishiguro, Takaaki Nomura, Hiroshi Okada +2
We study flavor phenomenologies in a basis of a double covering of modular group with a hidden symmetry, in which we work on regions at nearby two fixed points and th…
Upper bound on the Atiyah-Singer index from tadpole cancellation
Keiya Ishiguro, Takafumi Kai, Satsuki Nishimura +2
We propose an upper bound on the Atiyah-Singer index in the effective action of string theory. For and heterotic string theories on smooth Calabi-Y…
Flavor, CP and Metaplectic Modular Symmetries in Type IIB Chiral Flux Vacua
Takafumi Kai, Keiya Ishiguro, Hiroshi Okada +1
We examine symmetries of chiral four-dimensional vacua of Type IIB flux compactifications with vanishing superpotential . We find that the supersymmetric MSSM-lik…
Residual flavor symmetry breaking in the landscape of modular flavor models
Keiya Ishiguro, Hiroshi Okada, Hajime Otsuka
We study a symmetry breaking of residual flavor symmetries realized at fixed points of the moduli space. In the supersymmetric modular invariant theories, a small departure of the…
Symplectic modular symmetry in heterotic string vacua: flavor, CP, and -symmetries
Keiya Ishiguro, Tatsuo Kobayashi, Hajime Otsuka
We examine a common origin of four-dimensional flavor, CP, and symmetries in the context of heterotic string theory with standard embedding. We find that flavor and $U(1)_…
Sharpening the Boundaries Between Flux Landscape and Swampland by Tadpole Charge
Keiya Ishiguro, Hajime Otsuka
We investigate the vacuum structure of four-dimensional effective theory arising from Type IIB flux compactifications on a mirror of the rigid Calabi-Yau threefold, corresponding t…
Hierarchical structure of physical Yukawa couplings from matter field Kähler metric
Keiya Ishiguro, Tatsuo Kobayashi, Hajime Otsuka
We study the impacts of matter field Kähler metric on physical Yukawa couplings in string compactifications. Since the Kähler metric is non-trivial in general, the kinetic mixing o…
Landscape of Modular Symmetric Flavor Models
Keiya Ishiguro, Tatsuo Kobayashi, Hajime Otsuka
We study the moduli stabilization from the viewpoint of modular flavor symmetries. We systematically analyze stabilized moduli values in possible configurations of flux compactific…
Spontaneous CP violation and symplectic modular symmetry in Calabi-Yau compactifications
Keiya Ishiguro, Tatsuo Kobayashi, Hajime Otsuka
We explore the geometrical origin of CP and the spontaneous CP violation in Calabi-Yau compactifications. We find that the CP symmetry is identified with an outer automorphism of t…