Separability of N-particle Fermionic States for Arbitrary Partitions (2009)
Ichikawa, Tsubasa, Sasaki, Toshihiko, Tsutsui, Izumi
We present a criterion of separability for arbitrary s partitions of N-particle fermionic pure states. We show that, despite the superficial non-factorizability due to the antisymmetry required by...
Entanglement Measures for Intermediate Separability of Quantum States (2008)
Ichikawa, Tsubasa, Sasaki, Toshihiko, Tsutsui, Izumi
We present a family of entanglement measures R_m which act as indicators for separability of n-qubit quantum states into m subsystems for arbitrary 2 \leq m \leq n. The measure R_m vanishes if the...
Exchange Symmetry and Multipartite Entanglement (2008)
Ichikawa, Tsubasa, Sasaki, Toshihiko, Tsutsui, Izumi, Yonezawa, Nobuhiro
Entanglement of multipartite systems is studied based on exchange symmetry under the permutation group S_N. With the observation that symmetric property under the exchange of two constituent states...
Testing the EPR Locality using B-Mesons (2008)
Ichikawa, Tsubasa, Tamura, Satoshi, Tsutsui, Izumi
We study the possibility of testing local realistic theory (LRT), envisioned implicitly by Einstein, Podolsky and Rosen in 1935, based on the Bell inequality for the correlations in the decay modes...
Tsubasa Ichikawa, Izumi Tsutsui, Taksu Cheon
We present a novel formulation of quantum game theory based on the Schmidt decomposition, which has the merit that the entanglement of quantum strategies is manifestly quantified. We apply this...
Quantum Game Theory Based on the Schmidt Decomposition: Can Entanglement Resolve Dilemmas? (2007)
Ichikawa, Tsubasa, Tsutsui, Izumi, Cheon, Taksu
We present a novel formulation of quantum game theory based on the Schmidt decomposition, which has the merit that the entanglement of quantum strategies is manifestly quantified. We apply this...
Boundary effect of a partition in a quantum well (2006)
The paper wishes to demonstrate that, in quantum systems with boundaries, different boundary conditions can lead to remarkably different physical behaviour. Our seemingly innocent setting is a one...
Duality, Phase Structures and Dilemmas in Symmetric Quantum Games (2006)
Ichikawa, Tsubasa, Tsutsui, Izumi
Symmetric quantum games for 2-player, 2-qubit strategies are analyzed in detail by using a scheme in which all pure states in the 2-qubit Hilbert space are utilized for strategies. We consider two...
Inequivalent Quantizations of the N = 3 Calogero model with Scale and Mirror-S_3 Symmetry (2005)
Yonezawa, Nobuhiro, Tsutsui, Izumi
We study the inequivalent quantizations of the N = 3 Calogero model by separation of variables, in which the model decomposes into the angular and the radial parts. Our inequivalent quantizations...
Classical and Quantum Contents of Solvable Game Theory on Hilbert Space (2005)
A simple and general formulation of the quantum game theory is presented, accommodating all possible strategies in the Hilbert space for the first time. The theory is solvable for the two strategy...
Cheon, Taksu, Tsutsui, Izumi, Fulop, Tamas
We show that the U(2) family of point interactions on a line can be utilized to provide the U(2) family of qubit operations for quantum information processing. Qubits are realized as localized states...
Physics of singular points in quantum mechanics (2003)
Defects or junctions in materials serve as a source of interactions for particles, and in idealized limits they may be treated as singular points yielding contact interactions. In quantum mechanics,...
Quantum force due to distinct boundary conditions (2003)
Fulop, Tamas, Miyazaki, Hitoshi, Tsutsui, Izumi
We calculate the quantum statistical force acting on a partition wall that divides a one dimensional box into two halves. The two half boxes contain the same (fixed) number of noninteracting bosons,...
Spectral properties on a circle with a singularity (2003)
Fulop, Tamas, Tsutsui, Izumi, Cheon, Taksu
We investigate the spectral and symmetry properties of a quantum particle moving on a circle with a pointlike singularity (or point interaction). We find that, within the U(2) family of the quantum...
Duality Symmetry and Plane Waves in Non-Commutative Electrodynamics (2003)
Abe, Yasumi, Banerjee, Rabin, Tsutsui, Izumi
We generalise the electric-magnetic duality in standard Maxwell theory to its non-commutative version. Both space-space and space-time non-commutativity are necessary. The duality symmetry is then...
Supersymmetric Quantum Mechanics under Point Singularities (2003)
Uchino, Takashi, Tsutsui, Izumi
We provide a systematic study on the possibility of supersymmetry (SUSY) for one dimensional quantum mechanical systems consisting of a pair of lines $\R$ or intervals [-l, l] each having a point...
Supersymmetric Quantum Mechanics with a Point Singularity (2002)
Uchino, Takashi, Tsutsui, Izumi
We study the possibility of supersymmetry (SUSY) in quantum mechanics in one dimension under the presence of a point singularity. The system considered is the free particle on a line R or on the...
Connection Conditions and the Spectral Family under Singular Potentials (2002)
Tsutsui, Izumi, Fulop, Tamas, Cheon, Taksu
To describe a quantum system whose potential is divergent at one point, one must provide proper connection conditions for the wave functions at the singularity. Generalizing the scheme used for point...
Quantum Tunneling and Caustics under Inverse Square Potential (2002)
Miyazaki, Hitoshi, Tsutsui, Izumi
Quantization of a harmonic oscillator with inverse square potential $V(x)=(m{\omega^2}/2){x^2}+g/{x^2}$ on the line $-\infty
Classical Aspects of Quantum Walls in One Dimension (2001)
Fulop, Tamas, Cheon, Taksu, Tsutsui, Izumi
We investigate the system of a particle moving on a half line x >= 0 under the general walls at x = 0 that are permitted quantum mechanically. These quantum walls, characterized by a parameter L, are...
Spectral Structure of Quantum Line with a Defect (2001)
Cheon, Taksu, Fulop, Tamas, Tsutsui, Izumi
We study the spectral properties of one-dimensional quantum wire with a single defect. We reveal the existence of the non-trivial topological structures in the spectral space of the system, which are...
Moebius Structure of the Spectral Space of Schroedinger Operators with Point Interaction (2001)
Tsutsui, Izumi, Fulop, Tamas, Cheon, Taksu
The Schroedinger operator with point interaction in one dimension has a U(2) family of self-adjoint extensions. We study the spectrum of the operator and show that (i) the spectrum is uniquely...
Symmetry, Duality and Anholonomy of Point Interactions in One Dimension (2000)
Cheon, Taksu, Fulop, Tamas, Tsutsui, Izumi
We analyze the spectral structure of the one dimensional quantum mechanical system with point interaction, which is known to be parametrized by the group U(2). Based on the classification of the...
Instantons, Monopoles and the Flux Quantization in the Faddeev-Niemi Decomposition (2000)
Tsurumaru, Toyohiro, Tsutsui, Izumi, Fujii, Akira
We study how instantons arise in the low energy effective theory of the SU(2) Yang-Mills theory in the context of the non-linear sigma model recently propose by Faddeev and Niemi. We find a simple...
Duality and Anholonomy in Quantum Mechanics of 1D Contact Interactions (2000)
Tsutsui, Izumi, Fulop, Tamas, Cheon, Taksu
We study systems with parity invariant contact interactions in one dimension. The model analyzed is the simplest nontrivial one --- a quantum wire with a point defect --- and yet is shown to exhibit...
A Free Particle on a Circle with Point Interaction (1999)
The quantum dynamics of a free particle on a circle with point interaction is described by a U(2) family of self-adjoint Hamiltonians. We provide a classification of the family by introducing a...
Quantum Caustics for Systems with Quadratic Lagrangians in Multi-Dimensions (1999)
Horie, Kenichi, Miyazaki, Hitoshi, Tsutsui, Izumi
We study quantum caustics in $d$-dimensional systems with quadratic Lagrangians. Based on Schulman's procedure in the path-integral we derive the transition amplitude on caustics in a closed form for...
On Topological Terms in the O(3) Nonlinear Sigma Model (1999)
Tsurumaru, Toyohiro, Tsutsui, Izumi
Topological terms in the O(3) nonlinear sigma model in (1+1) and (2+1) dimensions are re-examined based on the description of the SU(2)-valued field $g$. We first show that the topological soliton...
Hopf Term, Fractional Spin and Soliton Operators in the O(3) Nonlinear Sigma Model (1998)
Tsutsui, Izumi, Kimura, Masaomi, Kobayashi, Hiroyuki
We re-examine three issues, the Hopf term, fractional spin and the soliton operators, in the 2+1 dimensional O(3) nonlinear sigma model based on the adjoint orbit parameterization (AOP) introduced...
Quantum Mechanically Induced Wess-Zumino Term in the Principal Chiral Model (1997)
Miyazaki, Hitoshi, Tsutsui, Izumi
It is argued that, in the two dimensional principal chiral model, the Wess-Zumino term can be induced quantum mechanically, allowing the model with the critical value of the coupling constant...
Quantum Mechanically Induced Hopf Term in the O(3) Nonlinear Sigma Model (1997)
Tsutsui, Izumi, Tanimura, Shogo, Kobayashi, Hiroyuki
The Hopf term in the $2 + 1$ dimensional O(3) nonlinear sigma model, which is known to be responsible for fractional spin and statistics, is re-examined from the viewpoint of quantization ambiguity....
Inequivalent Quantizations and Holonomy Factor from the Path-Integral Approach (1996)
Tanimura, Shogo, Tsutsui, Izumi
A path-integral quantization on a homogeneous space G/H is proposed based on the guiding principle `first lift to G and then project to G/H'. It is then shown that this principle gives a simple...
Quantum mechanical Liouville model with attractive potential (1996)
Kobayashi, Hiroyuki, Tsutsui, Izumi
We study the quantum mechanical Liouville model with attractive potential which is obtained by Hamiltonian symmetry reduction from the system of a free particle on $SL(2, \Real)$. The classical...
Regularization of Toda lattices by Hamiltonian reduction (1995)
The Toda lattice defined by the Hamiltonian $H={1\over 2} \sum_{i=1}^n p_i^2 + \sum_{i=1}^{n-1} \nu_i e^{q_i-q_{i+1}}$ with $\nu_i\in \{ \pm 1\}$, which exhibits singular (blowing up) solutions if...
Induced Gauge Fields in the Path Integral (1995)
Tanimura, Shogo, Tsutsui, Izumi
The path integral on a homogeneous space $ G/H $ is constructed, based on the guiding principle `first lift to $ G $ and then project to $ G/H $'. It is then shown that this principle admits...
The canonical connection in quantum mechanics (1995)
Levay, Peter, McMullan, David, Tsutsui, Izumi
In this paper we investigate the form of induced gauge fields that arises in two types of quantum systems. In the first we consider quantum mechanics on coset spaces G/H, and argue that G-invariance...
BPST instanton and Spin from inequivalent quantizations (1993)
McMullan, David, Tsutsui, Izumi
We present a simple alternative to Mackey's account of the (infinite) inequivalent quantizations possible on a coset space G/H. Our reformulation is based on the reduction ${\rm G \rightarrow G/H}$...
On the emergence of gauge structures and generalized spin when quantizing on a coset space (1993)
McMullan, David, Tsutsui, Izumi
It has been known for some time that there are many inequivalent quantizations possible when the configuration space of a system is a coset space G/H. Viewing this classical system as a constrained...