Results for "Shu Sasaki"

total 3521took 0.20s
Modularity lifting results in parallel weight one and applications to the Artin conjecture: the tamely ramified caseApr 03 2012May 21 2013We extend the modularity lifting result of the arXiv:1111.2804 to allow Galois representations with some ramification at p. We also prove modularity mod 2 and 5 of certain Galois representations. We use these results to prove many new cases of the strong ... More
Neural-network Kohn-Sham exchange-correlation potential and its out-of-training transferabilityFeb 08 2018We incorporate in the Kohn-Sham self consistent equation a trained neural-network projection from the charge density distribution to the Hartree-exchange-correlation potential $n \rightarrow V_{\rm Hxc}$ for possible numerical approach to the exact Kohn-Sham ... More
Neutrino Telescope Array Letter of Intent: A Large Array of High Resolution Imaging Atmospheric Cherenkov and Fluorescence Detectors for Survey of Air-showers from Cosmic Tau Neutrinos in the PeV-EeV Energy RangeAug 26 2014Jul 22 2015This Letter of Intent (LoI) describes the outline and plan for the Neutrino Telescope Array (NTA) project. High-energy neutrinos provide unique and indisputable evidence for hadronic acceleration. Recently, IceCube has reported astronomical neutrino candidates ... More
Theory of the Integer and Fractional Quantum Hall EffectsMar 29 2016The present theory has investigated the FQHE without any quasi-particle. The electric field due to the Hall voltage is taken into consideration. We find the ground state where the electron configuration is uniquely determined so as to have the minimum ... More
On Non-linear Action for Gauged M2-braneDec 04 2009Mar 17 2010We propose a non-linear extension of U(1) \times U(1) (abelian) ABJM model including T_{M2} (higher derivative) corrections. The action proposed here is expected to describe a single M2-brane proving C^4/Z_k target space. The model includes couplings ... More
The parity partner of the nucleon in quenched QCD with domain wall fermionsSep 11 1999We present preliminary results for the mass spectrum of the nucleon and its low-lying excited states from quenched lattice QCD using the domain wall fermion method which preserves the chiral symmetry at finite lattice cutoff. Definite mass splitting is ... More
Frequency Dependence of Diagonal Resistance in Fractional Quantum Hall Effect via Periodic Modulation of Magnetic FieldMar 05 2008Energy spectrum of fractional quantum Hall (FQH) states is composed of single electron energy (Landau energy) neglecting the Coulomb interactions between electrons, classical Coulomb energy and the quantum energy via quantum transitions. Herein, the sum ... More
Confining non-analytic exponential potential $V(x)= g^2\exp\,(2|x|)$ and its exact Bessel-function solvabilityNov 08 2016In a previous paper we have shown that Schr\"{o}dinger equation with the non-analytic attractive exponential potential $V(x)= -g^2\exp (-|x|)$ is exactly solvable. It has finitely many discrete eigenstates described by the Bessel function of the first ... More
Lattice study of exotic S=+1 baryonOct 06 2003Sep 21 2004We propose S=+1 baryon interpolating operators, which are based on an exotic description of the antidecuplet baryon like diquark-diqaurk-antiquark. By using one of the new operators, the mass spectrum of the spin-1/2 pentaquark states is calculated in ... More
Latest results from lattice QCD for the Roper resonanceMay 07 2003Jun 16 2003The present status of the Roper resonance in lattice QCD is reviewed. Some of the latest lattice results are discussed with particular emphasis on a large systematic error stemming from the finite size effect. These results suggest that the Roper resonance ... More
Evaluation of specific heat for superfluid helium between 0 - 2.1 K based on nonlinear theoryJul 09 2008The specific heat of liquid helium was calculated theoretically in the Landau theory. The results deviate from experimental data in the temperature region of 1.3 - 2.1 K. Many theorists subsequently improved the results of the Landau theory by applying ... More
Interplay between chromoelectric and chromomagnetic gluons in Yang-Mills thermodynamicsDec 18 2013We propose an effective theory of SU(3) gluonic matter where interactions between color-electric and color-magnetic gluons are constrained by the center and scale symmetries. Through matching to the dimensionally-reduced magnetic theories, the magnetic ... More
Thermodynamics of dense matter in chiral approachesApr 29 2010We discuss phases in dense hadronic and quark matter from chiral model approaches. Within PNJL models the phase diagram for various number of colors $N_c$ is studied. How phases are constrained in quantum field theories are also discussed along with the ... More
Chiral Thermodynamics with CharmFeb 27 2015Chiral thermodynamics of charmed mesons is formulated at finite temperature within a $2+1+1$-flavored effective Lagrangian incorporating heavy quark symmetry. The chiral mass splittings are shown to be less sensitive to the light-quark flavors, attributed ... More
Confining non-analytic exponential potential $V(x)= g^2\exp\,(2|x|)$ and its exact Bessel-function solvabilityNov 08 2016Nov 12 2016In a previous paper we have shown that Schr\"odinger equation with the non-analytic attractive exponential potential $V(x)= -g^2\exp (-|x|)$ is exactly solvable. It has finitely many discrete eigenstates described by the Bessel function of the first kind ... More
Visible actions on spherical nilpotent orbits in complex simple Lie algebrasSep 24 2015This paper studies nilpotent orbits in complex simple Lie algebras from the viewpoint of strongly visible actions in the sense of T. Kobayashi. We prove that the action of a maximal compact group consisting of inner automorphisms on a nilpotent orbit ... More
Spectral Analysis of the Dirac PolaronJun 09 2006Oct 22 2013A system of a Dirac particle interacting with the radiation field is considered. The Hamiltonian of the system is defined by $H = \alpha\cdot(\hat\mathbf{p}-q\mathbf{A}(\hat\mathbf{x}))+m\beta + H_f$ where $q\in\mathbb{R}$ is a coupling constant, $\mathbf{A}(\hat\mathbf{x})$ ... More
Yang-Mills Thermodynamics: an Effective Theory ApproachDec 13 2013We derive the Polyakov-loop thermodynamic potential in the perturbative approach to pure SU(3) Yang-Mills theory. The potential expressed in terms of the Polyakov loop in the fundamental representation corresponds to that of the strong-coupling expansion, ... More
Selected Issues in Thermal Field TheoryAug 04 2014New developments on hot and dense QCD in effective field theories are reviewed. Recent investigations in lattice gauge theories for the low-lying Dirac eigenmodes suggest survival hadrons in restored phase of chiral symmetry. We discuss expected properties ... More
The Phase Structure of Dense QCD from Chiral ModelsOct 22 2009A new phase of dense QCD proposed in the limit of large number of colors, Quarkyonic Phase, is discussed in chiral approaches. The interplay between chiral symmetry breaking and confinement together with the $N_c$ dependence of the phase diagram are dealt ... More
Inverse scattering for the nonlinear Schrödinger equation with the Yukawa potentialNov 05 2007Jun 25 2008We study the inverse scattering problem for the three dimensional nonlinear Schroedinger equation with the Yukawa potential. The nonlinearity of the equation is nonlocal. We reconstruct the potential and the nonlinearity by the knowledge of the scattering ... More
On link diagrams that are minimal with respect to Reidemeister moves I and IIDec 02 2016In this paper, a link diagram is said to be minimal if no Reidemeister move I or II can be applied to it to reduce the number of crossings. We show that for an arbitrary diagram D of a link without a trivial split component, a minimal diagram obtained ... More
N* Spectrum in Lattice QCDApr 27 2000Apr 28 2000We investigate the mass of the parity partner $N^* (1/2^{-})$ of the nucleon $N(1/2^{+})$, in lattice QCD using a new lattice discretization scheme for fermions, domain wall fermions (DWF). DWF possess exact chiral symmetry and flavor symmetry, both of ... More
A New Method to Estimate Cosmological Parameters Using Baryon Fraction of Clusters of GalaxiesNov 05 1996We propose a new method to estimate cosmological parameters using the baryon fraction of clusters of galaxies for a range of redshifts. The basic assumption is that the baryon fraction of clusters is constant, which is a reasonable assumption when it ... More
Exactly Solvable Birth and Death ProcessesMar 18 2009Many examples of exactly solvable birth and death processes, a typical stationary Markov chain, are presented together with the explicit expressions of the transition probabilities. They are derived by similarity transforming exactly solvable `matrix' ... More
Hyperon vector form factor from 2+1 flavor lattice QCDSep 27 2012Nov 26 2012We present the first result for the hyperon vector form factor f_1 for Xi^0 -> Sigma^+ l bar{nu} and Sigma^- -> n l bar{nu} semileptonic decays from fully dynamical lattice QCD. The calculations are carried out with gauge configurations generated by the ... More
Energy Spectra for Fractional Quantum Hall StatesAug 11 2007Fractional quantum Hall states (FQHS) with the filling factor nu = p/q of q < 21 are examined and their energies are calculated. The classical Coulomb energy is evaluated among many electrons; that energy is linearly dependent on 1/nu. The residual binding ... More
Pentaquarks: Status and Perspectives for Lattice CalculationsOct 13 2004The present status of pentaquark spectroscopy in lattice QCD is reviewed. This talk also includes a brief introduction of pentaquark baryons.
Lattice study of nucleon properties with domain wall fermionsOct 12 2001Domain wall fermions (DWF) are a new fermion discretization scheme with greatly improved chiral symmetry. Our final goal is to study the nucleon spin structure through lattice simulation using DWF. In this paper, we present our current progress on two ... More
Intracluster Supernova as a Possible Extra Energy Source of ClustersNov 09 2000The observed luminosity -- temperature relation of clusters is considerably steeper than that expected from a simple scaling relation. Although extra energy input is a likely solution, its source has not been identified. We propose intracluster supernova ... More
Hyperon vector coupling f_1(0) from 2+1 flavor lattice QCDFeb 24 2011We present results for the hyperon vector form factor f_1 for $\Xi^0 \rightarrow \Sigma^+ l\bar{\nu}$ and $\Sigma^- \rightarrow n l\bar{\nu}$ semileptonic decays from dynamical lattice QCD with domain-wall quarks. Simulations are performed on the 2+1 ... More
The QCD Phase Diagram from Chiral ApproachesJul 27 2009Sep 10 2009I show an updated QCD phase diagram with recent developments from chiral effective theories and phenomenological models. Expected signals of a QCD critical point accessible in heavy-ion collisions are also discussed. In particular, non-monotonic behavior ... More
Pion Velocity near the Chiral Phase TransitionApr 08 2004We focus on the pion velocity at the critical temperature and study the quantum and hadronic thermal effects based on the vector manifestation (VM). We show the non-renormalization property on the pion velocity $v_\pi$, which is protected by the VM, and ... More
On the life span of the Schrödinger equation with sub-critical power nonlinearityJul 03 2009We discuss the life span of the Cauchy problem for the one-dimensional Schr\"{o}dinger equation with a single power nonlinearity $\lambda |u|^{p-1}u$ ($\lambda\in\mathbb{C}$, $2\le p<3$) prescribed an initial data of the form $\varepsilon\varphi$. Here, ... More
Search for Sub-eV Sterile Neutrinos in the Precision Multiple Baselines Reactor Antineutrino Oscillation ExperimentsJan 01 2014Aug 14 2015According to different effects on neutrino oscillations, the unitarity violation in the MNSP matrix can be classified into the direct unitarity violation and the indirect unitarity violation which are induced by the existence of the light and the heavy ... More
Propensity score weighting for causal inference with multi-stage clustered dataJul 26 2016Propensity score weighting is a tool for causal inference to adjust for measured confounders. Survey data are often collected under complex sampling designs such as multistage cluster sampling, which presents challenges for propensity score modeling and ... More
From Hopf-Lax formula to optimal weak transfer planSep 12 2016We study the properties of Hopf-Lax formula restricted to convex functions and characterize the optimal transfer plan for weak transport problem.
One loop quantum fluctuations to the energy of the non-topological soliton in Friedberg-Lee modelJul 06 2016I have used a practical method to calculate the one-loop quantum correction to the energy of the non-topological soliton in Friedberg-Lee model. The quantum effects which come from the quarks of the Dirac sea scattering with the soliton bag are calculated ... More
Spontaneous Lorentz Violation and BaryogenesisNov 15 2007Dec 18 2007In the presence of background fields that spontaneously violate Lorentz invariance, a matter-antimatter asymmetry can be generated even in thermal equilibrium. In this paper we systematically investigate models of this type, showing that either high-energy ... More
Microlocal resolvent estimates, revisitedFeb 10 2016Apr 25 2016Let $H$ be a Schr\"odinger type operator with long-range perturbation. We study the wave front set of the distribution kernel of $(H-\lambda\mp i0)^{-1}$, where $\lambda$ is in the absolutely continous spectrumof $H$.The result is a refinement of the ... More
A Remark on the Mourre Theory for Two Body Schrödinger operatorsMay 21 2013May 31 2013On this short note, we apply the Mourre theory of the limiting absorption with {\it difference} type conditions on the potential, instead of conditions on the derivatives. In order that we modify the definition of the conjugate operator, and we apply ... More
Unstable Kodaira FibrationsDec 19 2006Being inspired by Ross' construction of unstable products of certain smooth curves, we show that the product $C\times C$ of every smooth curve $C$ of genus at least 2 is not slope semistable with respect to certain polarisations. Besides, we produce examples ... More
Dirac Lepton Angle Matrix v.s. Majorana Lepton Angle Matrix and Their Renormalization Group Running BehavioursSep 20 2011Dec 14 2011Enlightened by the idea of the 3 times 3 CKM angle matrix proposed recently by Harrison et al., we introduce the Dirac angle matrix Phi and the Majorana angle matrix Psi in the lepton sector for Dirac and Majorana neutrinos respectively. We show that ... More
Semiclassical Singularity Propagation Property for Schrödinger EquationsMay 30 2006Sep 18 2007We consider Schr\"odinger equations with variable coefficients, and it is supposed to be a long-range type perturbation of the flat Laplacian on $R^n$. We characterize the wave front set of solutions to Schr\"odinger equations in terms of the initial ... More
Conjugacy of Borel subalgebras of restricted Lie algeberas and the associated solvabel algebraic groups (I)Apr 04 2014Let (g,[p]) be a finite-dimensional restricted Lie algebra defined over an algebraically closed field K of characteristic p > 0, and G be the adjoint group of g. A Borel subalgebra (or Borel for short) of g is defined as a maximal solvable subalgebra ... More
Compact Complex Surfaces and Constant Scalar Curvature Kähler MetricsDec 01 2006Sep 26 2008In this article, I prove the following statement: Every compact complex surface with even first Betti number is deformation equivalent to one which admits an extremal K\"ahler metric. In fact, this extremal K\"ahler metric can even be taken to have constant ... More
Holographic thermalization with initial long range correlationNov 24 2015Feb 12 2016We studied the evolution of Wightman correlator in a thermalizing state modeled by AdS_3-Vaidya background. We gave a prescription for calculating Wightman correlator in coordinate space without using any approximation. For equal-time correlator $\langle ... More
Unitarity Bounds for New Physics from Axial Coupling at LHCNov 15 2007If a new massive vector boson with nonzero axial couplings to fermions will be observed at LHC, then an upper limit on the scale of new physics could be derived from unitarity of $\mathcal{S}$-matrix. The new physics will involve either new massive fermions, ... More
Symmetric confidence regions and confidence intervals for normal map formulations of stochastic variational inequalitiesJun 26 2014Stochastic variational inequalities (SVI) model a large class of equilibrium problems subject to data uncertainty, and are closely related to stochastic optimization problems. The SVI solution is usually estimated by a solution to a sample average approximation ... More
Microlocal properties of scattering matricesJul 31 2014We consider scattering theory for a pair of operators $H_0$ and $H=H_0+V$ on $L^2(M,m)$, where $M$ is a Riemannian manifold, $H_0$ is a multiplication operator on $M$ and $V$ is a pseudodifferential operator of order $-\mu$, $\mu>1$. We show that a time-dependent ... More
On the List Decodability of Self-orthogonal Rank Metric CodesJan 22 2018V. Guruswami and N. Resch prove that the list decodability of $\mathbb{F}_q$-linear rank metric codes is as good as that of random rank metric codes in~\cite{venkat2017}. Due to the potential applications of self-orthogonal rank metric codes, we focus ... More
Stability of Q-balls and CatastropheDec 10 2007Jun 05 2008We propose a practical method for analyzing stability of Q-balls for the whole parameter space, which includes the intermediate region between the thin-wall limit and thick-wall limit as well as Q-bubbles (Q-balls in false vacuum), using the catastrophe ... More
BPS States in Supersymmetric Chiral Models with Higher Derivative TermsJun 30 2014Nov 04 2014We study the higher derivative chiral models with four supercharges and BPS states in these models. The off-shell Lagrangian generically includes higher powers of the auxiliary fields F which causes distinct on-shell branches associated with the solutions ... More
A Conclusive Test of Abelian Dominance Hypothesis for Topological Charge in the QCD VacuumAug 18 1998Sep 12 1998We study the topological feature in the QCD vacuum based on the hypothesis of abelian dominance. The topological charge $Q_{\rm SU(2)}$ can be explicitly represented in terms of the monopole current in the abelian dominated system. To appreciate its justification, ... More
Existence of Chiral-Asymmetric Zero Modes in the Background of QCD-MonopolesSep 19 1997We study topological aspects of the QCD vacuum structure in SU(2) lattice gauge theory with the abelian gauge fixing. The index of the Dirac operator is measured by using the Wilson fermion in the quenched approximation. We find chiral-asymmetric zero ... More
$U_A$(1) Anomaly in Background Fields Dominated by QCD-Monopoles on SU(2) LatticeJun 01 1997Jun 13 1997We study $U_A$(1) anomaly of non-perturbative QCD in the maximally abelian gauge on SU(2) lattice. The existence of the strong correlation between QCD-monopoles and instantons in the abelian gauge is shown by both analytic and numerical works including ... More
Classifying BPS States in Supersymmetric Gauge Theories Coupled to Higher Derivative Chiral ModelsApr 30 2015Jun 21 2015We study N=1 supersymmetric gauge theories coupled with higher derivative chiral models in four dimensions in the off-shell superfield formalism. We solve the equation of motion for the auxiliary fields and find two distinct on-shell structures of the ... More
Superconducting Sn_{1-x}In_{x}Te NanoplatesOct 17 2014May 21 2015Recently, the search for Majorana fermions has become one of the most prominent subjects in condensed matter physics. This search involves explorations of new materials and hence offers interesting opportunities for chemistry. Theoretically, Majorana ... More
Non-equilibrium Ionization State of Warm-Hot Intergalactic MediumMar 03 2006Jun 13 2006Time evolution of the ionization state of metals in the cosmic baryons is investigated in a cosmological context without the assumption of ionization equilibrium. We find that a significant fraction of ionized oxygen ions (OVII and OVIII) in the warm-hot ... More
Numerical study of tree-level improved lattice gradient flows in pure Yang-Mills theorySep 22 2016Sep 29 2016We study several types of tree-level improvement in the Yang-Mills gradient flow method in order to reduce the lattice discretization errors in line with a reference [Fodor et al., arXiv:1406.0827]. The tree-level $\mathcal{O}(a^2)$ improvement can be ... More
Enhanced binding for N-particle system interacting with a scalar bose field ISep 29 2006An enhanced binding of an $N$-particle system interacting through a scalar bose field is investigated, where $N\geq 2$. It is not assumed that this system has a ground state for a zero coupling. It is shown, however, that there exists a ground state for ... More
Binding condition for a general class of quantum field HamiltoniansJun 21 2012We consider a system of a quantum particle interacting with a quantum field and an external potential $V(\bx)$. The Hamiltonian is defined by a quadratic form $H^V = H^0 + V(\bx)$, where $H^0$ is a quadratic form which preserves the total momentum. $H^0$ ... More
Worldsheet Instanton Corrections to 522-brane GeometryMay 20 2013Sep 12 2013We study worldsheet instanton corrections to the exotic 522-brane geometry in type II string theory. The BPS vortices in the N=(4,4) gauged linear sigma model modify the geometry of the 522-brane. We find that the modification of the geometry is understood ... More
Gauged Linear Sigma Model for Exotic Five-braneApr 15 2013Mar 19 2014We study an N=(4,4) supersymmetric gauged linear sigma model which gives rise to the nonlinear sigma model for multi-centered KK-monopoles. We find a new T-duality transformation of the model even in the presence of F-terms. Performing T-duality, we find ... More
Sigma Model BPS Lumps on TorusMay 27 2012Sep 19 2012We study doubly periodic Bogomol'nyi-Prasad-Sommerfield (BPS) lumps in supersymmetric CP^{N-1} non-linear sigma models on a torus T^2. Following the philosophy of the Harrington-Shepard construction of calorons in Yang-Mills theory, we obtain the n-lump ... More
Lattice Study of $U_{A}(1)$ Anomaly: The Role of QCD-MonopolesOct 20 1998We investigate the role of QCD-monopoles for the $U_{A}(1)$ anomaly in the maximally abelian gauge within the SU(2) lattice gauge theory. The existence of the strong correlation between instantons and QCD-monopoles in the abelian gauge was already shown ... More
Thermal Dilepton Production Rate from Dropping rho in the Vector ManifestationSep 25 2007In this write-up we summarize main points of our recent analysis on the thermal dilepton production rate from the dropping rho based on the vector manifestation (VM). In the analysis, we studied the effect of the strong violation of the vector dominance ... More
Vector Manifestation and Violation of Vector Dominance in Hot MatterApr 30 2003Mar 15 2004We show the details of the calculation of the hadronic thermal corrections to the two-point functions in the effective field theory of QCD for pions and vector mesons based on the hidden local symmetry (HLS) in hot matter using the background field gauge. ... More
Effect of vector--axial-vector mixing to dilepton spectrumMar 01 2010In this write-up we summarize main results of our recent analyses on the mixing between transverse rho and a1 mesons in hot and/or dense matter. We show that the axial-vector meson contributes significantly to the vector spectral function in hot matter ... More
Dropping rho and A1 Meson Masses at the Chiral Phase Transition in the Generalized Hidden Local SymmetryMar 22 2007In this contribution to the proceedings, we present our recent analysis on the chiral symmetry restoration in the generalized hidden local symmetry (GHLS) which incorporates the rho meson, $A_1$ meson and the pion consistently with the chiral symmetry ... More
Dropping rho and A_1 Meson Masses at Chiral Phase Transition in the Generalized Hidden Local SymmetryNov 28 2005Jan 16 2006We study the chiral symmetry restoration using the generalized hidden local symmetry (GHLS) which incorporates the rho and A_1 mesons as the gauge bosons of the GHLS and the pion as the Nambu-Goldstone boson consistently with the chiral symmetry of QCD. ... More
Mass effects in the polarized virtual photon structureJun 07 2004We discuss target mass effects in the polarized virtual photon structure functions $g_1^\gamma (x,Q^2,P^2)$, $g_2^\gamma (x,Q^2,P^2)$ for the kinematic region $\Lambda^2\ll P^2 \ll Q^2$, where $-Q^2 (-P^2)$ is the mass squared of the probe (target) photon. ... More
Parton Distributions in the Virtual Photon Target and Factorization Scheme DependenceJun 02 2000We investigate parton distributions in the virtual photon target, both polarized and unpolarized, up to the next-leading order (NLO) in QCD. Parton distributions can be predicted completely up to NLO, but they are factorization-scheme-dependent. We analyze ... More
Polarized Virtual Photon Structure Function in the Next-to-leading Order in QCDDec 16 1998The virtual photon structure function $g_1^{\gamma}(x,Q^2,P^2)$, which can be obtained in polarized $e^{+}e^{-}$ colliding-beam experiments, is investigated for $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is the mass squared of the probe (target) ... More
Newton's law on an Einstein "Gauss-Bonnet" braneJun 09 2003Aug 19 2003It is known that Newton's law of gravity holds asymptotically on a flat "brane" embedded in an anti-de Sitter "bulk" ; this was shown not only when gravity in the bulk is described by Einstein's theory but also in Einstein "Lanczos Lovelock Gauss-Bonnet"'s ... More
Boltzmann limit and quasifreeness for a homogenous Fermi gas in a weakly disordered random mediumNov 06 2007Apr 24 2008We discuss some basic aspects of the dynamics of a homogenous Fermi gas in a weak random potential, under negligence of the particle pair interactions. We derive the kinetic scaling limit for the momentum distribution function with a translation invariant ... More
Super-Horizon Scale Dynamics of Multi-Scalar InflationJan 08 1998Mar 16 1998We consider the dynamics of a multi-component scalar field on super-horizon scales in the context of inflationary cosmology. We present a method to solve the perturbation equations on super- horizon scales, i.e., in the long wavelength limit, by using ... More
Circular phase of a two dimensional ferromagnet with dipolar interactionsMay 01 1996We make for the first time a large-scale Monte-Carlo simulation of a ferromagnetic Heisenberg model with dipolar interactions on a two dimensional square lattice with open boundaries using an efficient new technique. We find that a phase transition occurs ... More
Hamiltonian Analysis of an On-shell U(1) Gauge Field TheoryOct 11 2016We perform the Hamiltonian analysis of an on-shell U(1) gauge field theory, in which the action is not invariant under local U(1) transformations but recovers the invariance when the equations of motion are imposed. We firstly apply Dirac's method of ... More
On the ionization energy of the semi-relativistic Pauli-Fierz model for a single particleMar 08 2010Apr 02 2010A semi-relativistic Pauli-Fierz model is defined by the sum of the free Hamiltonian $H_{\rm f}$ of a Boson Fock space, an nuclear potential $V$ and a relativistic kinetic energy: $$ H=\sqrt{[\sigma\cdot(\mathbf{p}+e\mathbf{A})]^2+M^2} - M + V + H_{\rm ... More
Gradient expansion approach to nonlinear superhorizon perturbationsDec 29 2006Mar 31 2007Using the gradient expansion approach, we formulate a nonlinear cosmological perturbation theory on super-horizon scales valid to $O(\epsilon^2)$, where $\epsilon$ is the expansion parameter associated with a spatial derivative. For simplicity, we focus ... More
Gradient expansion approach to nonlinear superhorizon perturbations II -- a single scalar field --Jun 05 2007Jun 14 2007We formulate nonlinear perturbations of a scalar field dominated universe on super-horizon scales. We consider the case of a single scalar field. We take the gradient expansion approach. We adopt the uniform Hubble slicing and derive the general solution ... More
Embedded Eigenvalues and Neumann-Wigner Potentials for Relativistic Schrodinger OperatorsMay 01 2016May 11 2016We construct Neumann-Wigner type potentials for the massive relativistic Schrodinger operator in one and three dimensions for which an eigenvalue embedded in the bsolutely continuous spectrum exists. First we consider the relativistic variants of the ... More
Boosted perturbations at the end of inflationNov 11 2009Jan 26 2010We study the effect on the primordial cosmological perturbations of a sharp transition from inflationary to a radiation and matter dominated epoch respectively. We assume that the perturbations are generated by the vacuum fluctuations of a scalar field ... More
Off-shell construction of superconformal Chern-Simons theories in three dimensionsDec 29 2011May 26 2012We propose an off-shell construction of three-dimensional N = 3 and N = 4 superconformal Abelian Chern-Simons theories in the projective superspace formalism. We also construct coupling terms among the gauge fields and matter hypermultiplets.
Conditional generation of an arbitrary superposition of coherent statesFeb 13 2007We present a scheme to conditionally generate an arbitrary superposition of a pair of coherent states from a squeezed vacuum by means of the modified photon subtraction where a coherent state ancilla and two on/off type detectors are used. We show that, ... More
Analytic black hole perturbation approach to gravitational radiationJun 27 2003We review analytic methods to perform the post-Newtonian expansion of gravitational waves induced by a particle orbiting a massive compact body, based on the black hole perturbation theory. There exist two different methods of the post-Newtonian expansion. ... More
Spin Structure Function of the Virtual Photon Beyond the Leading Order in QCDDec 30 1998Polarized photon structure can be studied in the future polarized $e^{+}e^{-}$ colliding-beam experiments. We investigate the spin-dependent structure function of the virtual photon $g_1^{\gamma}(x,Q^2,P^2)$, in perturbative QCD for $\Lambda^2 \ll P^2 ... More
Heating of the Hot Intergalactic Medium by Powerful Radio Galaxies and Associated High Energy Gamma-Ray EmissionJun 11 2001Aug 01 2001There is increasing evidence that some heating mechanism in addition to gravitational shock heating has been important for the hot gas inside clusters and groups of galaxies, as indicated by their observed X-ray scaling properties. While supernovae are ... More
Quantized gravitational waves in the Milne universeOct 25 1996The quantization of gravitational waves in the Milne universe is discussed. The relation between positive frequency functions of the gravitational waves in the Milne universe and those in the Minkowski universe is clarified. Implications to the one-bubble ... More
No supercritical supercurvature mode conjecture in one-bubble open inflationAug 06 1998In the path integral approach to false vacuum decay with the effect of gravity, there is an unsolved problem, called the negative mode problem. We show that the appearance of a supercritical supercurvature mode in the one-bubble open inflation scenario ... More
Non-Abelian Gauge Groups and Hypermultiplets in Projective SuperspacesDec 30 2012Apr 13 2013We construct off-shell superconformal actions of hypermultiplets coupled with non-Abelian gauge multiplets in three-dimensional N = 3 and N = 4 projective superspaces. We establish the explicit embeddings of the N = 2 vector and adjoint chiral superfields, ... More
Simplified Expressions of the Multi-indexed Laguerre and Jacobi PolynomialsDec 03 2016The multi-indexed Laguerre and Jacobi polynomials form a complete set of orthogonal polynomials. They satisfy second order differential equations but not three term recurrence relations, because of the `holes' in their degrees. The multi-indexed Laguerre ... More
Stochastic Cutoff Method for Long-Range Interacting SystemsOct 05 2007Dec 27 2007A new Monte-Carlo method for long-range interacting systems is presented. This method consists of eliminating interactions stochastically with the detailed balance condition satisfied. When a pairwise interaction $V_{ij}$ of a $N$-particle system decreases ... More
Post-Newtonian expansion of gravitational waves from a particle in circular orbit around a Schwarzschild black holeMay 26 1994Based upon the formalism recently developed by one of us (MS), we analytically perform the post-Newtonian expansion of gravitational waves from a test particle in circular orbit of radius $r_0$ around a Schwarzschild black hole of mass $M$. We calculate ... More
Black hole formation in the Friedmann universe: Formulation and computation in numerical relativityMay 18 1999We study formation of black holes in the Friedmann universe. We present a formulation of the Einstein equations under the constant mean curvature time-slicing condition. Our formalism not only gives us the analytic solution of the perturbation equations ... More
Lax pair for SU(n) Hubbard modelJan 20 1998Jan 30 1998For one dimensional SU(n) Hubbard model, a pair of Lax operators are derived, which give a set of fundamental equations for the quantum inverse scattering method under both periodic and open boundary conditions. This provides another proof of the integrability ... More
Quantum & Classical Eigenfunctions in Calogero & Sutherland SystemsAug 07 2003Sep 10 2003An interesting observation was reported by Corrigan-Sasaki that all the frequencies of small oscillations around equilibrium are " quantised" for Calogero and Sutherland (C-S) systems, typical integrable multi-particle dynamics. We present an analytic ... More
Quantum vs Classical Integrability in Ruijsenaars-Schneider SystemsMay 14 2003The relationship (resemblance and/or contrast) between quantum and classical integrability in Ruijsenaars-Schneider systems, which are one parameter deformation of Calogero-Moser systems, is addressed. Many remarkable properties of classical Calogero ... More
Numerical study of tree-level improved lattice gradient flows in pure Yang-Mills theorySep 22 2016We study several types of tree-level improvement in the Yang-Mills gradient flow method in order to reduce the lattice discretization errors in line with a reference [Fodor et al., arXiv:1406.0827]. The tree-level $\mathcal{O}(a^2)$ improvement can be ... More