83 citations · 140 across the 19 of their papers we have counts for
19 papers
Stable homotopy theory of invertible gapped quantum spin systems I: Kitaev's -spectrum
Yosuke Kubota
We provide a mathematical realization of a conjecture by Kitaev, on the basis of the operator-algebraic formulation of infinite quantum spin systems. Our main results are threefold…
Groupoid homology and K-theory for algebraic actions from number theory
Chris Bruce, Yosuke Kubota, Takuya Takeishi
We compute the groupoid homology for the ample groupoids associated with algebraic actions from rings of algebraic integers and integral dynamics. We derive results for the homolog…
Tensor category equivariant KK-theory
Yuki Arano, Kan Kitamura, Yosuke Kubota
In this paper, we introduce Kasparov's bivariant K-theory that is equivariant under symmetries of a C*-tensor category. It is motivated by some dualities in quantum group equivaria…
Delocalized spectra of Landau operators on helical surfaces
Yosuke Kubota, Matthias Ludewig, Guo Chuan Thiang
On a flat surface, the Landau operator, or quantum Hall Hamiltonian, has spectrum a discrete set of infinitely degenerate Landau levels. We consider surfaces with asymptotically co…
Band width and the Rosenberg index
Yosuke Kubota
A Riemannian manifold is said to have infinite -width if it admits an isometric immersion of an arbitrarily wide Riemannian band whose inward boundary has non-trivial…
The bulk-dislocation correspondence for weak topological insulators on screw-dislocated lattices
Yosuke Kubota
A weak topological insulator in dimension is known to have a topologically protected gapless mode along the screw dislocation. In this paper we formulate and prove this fact wi…
Codimension 2 transfer of higher index invariants
Yosuke Kubota
This paper is devoted to the study of the higher index theory of codimension submanifolds originated by Gromov-Lawson and Hanke-Pape-Schick. The first main result is to constru…
Twisted crystallograpic T-duality via the Baum--Connes isomorphism
Kiyonori Gomi, Yosuke Kubota, Guo Chuan Thiang
We establish the twisted crystallographic T-duality, which is an isomorphism between Freed-Moore twisted equivariant K-groups of the position and momentum tori associated to an ext…
The index theorem of lattice Wilson--Dirac operators via higher index theory
Yosuke Kubota
We give a proof of the index theorem of lattice Wilson--Dirac operators, which states that the index of a twisted Dirac operator on the standard torus is described in terms of the…
The Gromov-Lawson codimension 2 obstruction to positive scalar curvature and the C*-index
Yosuke Kubota, Thomas Schick
Gromov and Lawson developed a codimension 2 index obstruction to positive scalar curvature for a closed spin manifold M, later refined by Hanke, Pape and Schick. Kubota has shown t…
The relative Mishchenko--Fomenko higher index and almost flat bundles II: Almost flat index pairing
Yosuke Kubota
This is the second part of a series of papers which bridges the Chang--Weinberger--Yu relative higher index and geometry of almost flat hermitian vector bundles on manifolds with b…
Almost flat relative vector bundles and the almost monodromy correspondence
Yosuke Kubota
In this paper we introduce the notion of almost flatness for (stably) relative bundles on a pair of topological spaces and investigate basic properties of it. First, we show that a…
The relative Mishchenko--Fomenko higher index and almost flat bundles I: The relative Mishchenko--Fomenko index
Yosuke Kubota
In this paper, the first of two, we introduce an alternative definition of the Chang--Weinberger--Yu relative higher index, which is thought of as a relative analogue of the Mishch…
Reconstructing the Bost--Connes semigroup actions from K-theory
Yosuke Kubota, Takuya Takeishi
We complete the classification of Bost--Connes systems. We show that two Bost--Connes C*-algebras for number fields are isomorphic if and only if the original semigroups actions ar…
Compact Lie group actions with continuous Rokhlin property
Yuki Arano, Yosuke Kubota
In this paper, we study continuous Rokhlin property of -dynamical systems using techniques of equivariant -theory and quantum group theory. In particular…
Controlled topological phases and bulk-edge correspondence
Yosuke Kubota
In this paper, we introduce a variation of the notion of topological phase reflecting metric structure of the position space. This framework contains not only periodic and non-peri…
Notes on twisted equivariant -theory for -algebras
Yosuke Kubota
In this paper, we study a generalization of twisted (groupoid) equivariant -theory in the sense of Freed-Moore for -graded -algebras. It is…
A categorical perspective on the Atiyah-Segal completion theorem in -theory
Yuki Arano, Yosuke Kubota
We investigate the homological ideal , the kernel of the restriction functors in compact Lie group equivariant Kasparov categories. Applying the relative homologi…
The Joint Spectral Flow and Localization of the Indices of Elliptic Operators
Yosuke Kubota
We introduce the notion of the joint spectral flow, which is a generalization of the spectral flow, by using Segal's model of the connective -theory spectrum. We apply it for so…