12 citations · 56 across the 19 of their papers we have counts for
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Essential self-adjointness for the Klein-Gordon type operators on asymptotically static spacetime
Shu Nakamura, Kouichi Taira
Let be the spacetime, where is a closed manifold equipped with a Riemannian metric , and we consider a symmetric Klein-Gordon type operator on …
A remark on the essential self-adjointness for Klein-Gordon type operators
Shu Nakamura, Kouichi Taira
Here we discuss a new simplified proof of the essential self-adjointness for formally self-adjoint differential operators of real principal type, previously proved by Vasy (2020) a…
Remarks on the geodesically completeness and the smoothing effect on asymptotically Minkowski spacetimes
Kouichi Taira
In this note, we study a geometric property of asymptotically Minkowski spacetimes and an analytic property of the Klein-Gordon operator. Precisely, our first main results show tha…
Limiting absorption principle and equivalence of Feynman propagators on asymptotically Minkowski spacetimes
Kouichi Taira
In this paper, we shall show that the limiting absorption principle for the wave operator on the asymptotically Minkowski spacetime. This problem was previously considered by [A. V…
Some properties of threshold eigenstates and resonant states of discrete Schrödinger operators
Yuji Nomura, Kouichi Taira
In this note, we study some properties of threshold resonant states or threshold eigenfunctions for discrete Schrödinger operators. We mainly prove two theorems. First, we prove th…
Uniform bounds of discrete Birman-Schwinger operators
Yukihide Tadano, Kouichi Taira
In this note, uniform bounds of the Birman-Schwinger operators in the discrete setting are studied. For uniformly decaying potentials, we obtain the same bound as in the continuous…