K. Ohashi

collaborators

3 papers

hep-th2026

Ghost-Free Stable Minkowski Vacua in Lovelock Compactifications on Irreducible Symmetric Spaces

Keisuke Ohashi

We study the compactification of higher-dimensional Lovelock gravity on compact irreducible symmetric spaces, focusing on conditions under which a physically healthy four-dimension…

hep-th2025

Fractional instantons in 2d $C P^{N - 1}$ model and 4d Yang-Mills theory with 't Hooft twists

Yui Hayashi, Tatsuhiro Misumi, Muneto Nitta +2

We derive the explicit formula for fractional BPS lumps (or fractional instantons) in the $C P^{N - 1}$ nonlinear sigma model on a two-dimensional torus under various shift-c…

hep-th2025

String junctions in flag manifold sigma model

Yuki Amari, Toshiaki Fujimori, Muneto Nitta +1

We numerically construct a stable three-string junction of Y-shape in a flag manifold nonlinear sigma model on $S U (3) / U (1)^{2}$ .

Ghost-Free Stable Minkowski Vacua in Lovelock Compactifications on Irreducible Symmetric Spaces

Fractional instantons in 2d CPN−1 model and 4d Yang-Mills theory with 't Hooft twists

String junctions in flag manifold sigma model

Fractional instantons in 2d $C P^{N - 1}$ model and 4d Yang-Mills theory with 't Hooft twists