collaborators

7 papers

hep-th2026

Effective Dynamics of Inflationary End-of-the-World Branes in AdS

Kosei Fujiki, Michitaka Kohara, Jason Kristiano +2

We develop an effective description of a two-dimensional cosmological end-of-the-world brane embedded in AdS, with a scalar field localized on the brane. Integrating out bulk d…

hep-th2026

Detecting one-dimensional bosonic SPT phases via twisted entropic order parameter

Kosei Fujiki, Tsubasa Oishi, Soichiro Shimamori

Entanglement asymmetry, introduced by F. Ares, S. Murciano and P. Calabrese, provides a density-matrix diagnostic of symmetry breaking and successfully captures the Landau data ass…

hep-th2026

de Sitter holography from a Lorentzian torus

Kosei Fujiki, Michitaka Kohara, Javier Moreno +2

We show that the quantum entanglement between the conformal field theories (CFTs) living on the future and past boundaries in the de Sitter/conformal field theory (dS/CFT) correspo…

hep-th2026

The Entanglement Wedge Polygon

Kosei Fujiki, Jonathan Harper, Tadashi Takayanagi +1

In this work we consider a particular codimension-1 region of a holographic spacetime which we call the entanglement wedge polygon (EWP). For a pure state and a partition of the bo…

hep-th2026

Saddle Incompatibility Generates Genuine Multientropy in Heavy Local Quenches

Kosei Fujiki, Kenya Tasuki

We study the time evolution of tripartite genuine multientropy in heavy local quenches via AdS/CFT. Its linear response around the vacuum cancels pointwise for arbitrar…

hep-th2025

Entropic Interpretation of Einstein Equation in dS/CFT

Kosei Fujiki, Michitaka Kohara, Kotaro Shinmyo +2

In this paper, we demonstrate that the first law of holographic pseudo-entropy, which is a non-Hermitian generalization of entanglement entropy in a two-dimensional conformal field…

hep-th2025

Brane Cosmology from AdS/BCFT

Kosei Fujiki, Hiroki Kanda, Michitaka Kohara +1

In this paper, we study the time-dependent dynamics of an end-of-the-world (EOW) brane in AdS with a scalar field localized on the brane. We mainly studied several aspects of holog…