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Results for "Nobuyuki Abe"

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Deterministic reshaping of single-photon spectra using cross-phase modulationApr 07 2016The frequency conversion of light has proved to be a crucial technology for communication, spectroscopy, imaging, and signal processing. In the quantum regime, it also offers great potential for realizing quantum networks incorporating disparate physical ... More
Dynamic Monopoles and Spacetime StructureDec 28 1995Jan 08 1996According to previous work on magnetic monopoles, static regular solutions are nonexistent if the vacuum expectation value of the Higgs field $\eta$ is larger than a critical value $\eta_{{\rm cr}}$, which is of the order of the Planck mass. In order ... More
Generality of Topological InflationJul 21 2003Oct 30 2003Many authors claimed that a large initial inhomogeneity prevents the onset of inflation and therefore inflation takes place only if the scalar field is homogeneous or appropriately chosen over the horizon scale. We show that those arguments do not apply ... More
Topological Defect InflationDec 31 1999Jan 01 2000We address some issues of topological defect inflation. (1) We clarify the causal structure of an inflating magnetic monopole. The spacetime diagram shows explicitly that this model is free from the ``graceful exit'' problem, while the monopole itself ... More
Fluctuations of the Gravitational Constant Induced by Primordial BubblesJan 11 1996Apr 20 1996We consider the classical fluctuations of the gravitational constant generated by bubbles in the inflationary universe. For extended inflation, we demonstrate numerically how and how large fluctuations are produced during bubble expansion. The amplitude ... More
2D String Theory Coupled to Quantum GravityMay 14 1993May 18 1993We consider self-avoiding Nambu-Goto open strings on a random surface. We have shown that the partition function of such a string theory can be calculated exactly. The string susceptibility for the disk is evaluated to be $-\frac{1}{2}$. We also consider ... More
Relationship between mass density, electron density, and elemental composition of body tissues for Monte Carlo simulation in radiation treatment planningAug 02 2015Purpose: For Monte Carlo simulation of radiotherapy, x-ray CT number of every system needs to be calibrated and converted to mass density and elemental composition. This study aims to formulate material properties of body tissues for practical two-step ... More
Dynamics of Gravitating Magnetic MonopolesDec 28 1995Apr 21 1996According to previous work on magnetic monopoles, static regular solutions are nonexistent if the vacuum expectation value of the Higgs field $\eta$ is larger than a critical value $\eta_{{\rm cr}}$, which is of the order of the Planck mass. In order ... More
p-branes from (p-2)-branes in the Bosonic String TheoryApr 25 1998May 15 1998We show that Dirichlet p-brane can be expressed as a configuration of infinitely many Dirichlet (p-2)-branes in the bosonic string theory. Using this fact, we interpret the massless fields on the p-brane worldvolume as deformations of the configuration ... More
Extra Observables in Gauged WZW ModelsOct 30 1991It is known that Liouville theory can be represented as an SL(2,R) gauged WZW model. We study a two dimensional field theory which can be obtained by analytically continuing some of the variables in the SL(2,R) gauged WZW model. We can derive Liouville ... More
Freeness of adjoint linear systems on threefolds with non Gorenstein Q-factorial terminal singularities or some quotient singularitiesJan 22 2001Mar 14 2001We define and calculate the weighted multiplicities of non Gorenstein terminal singularities on threefolds and some quotient singularities. We improve freeness conditions on threefolds.
A weak-value model for virtual particles supplying the electric current in graphene: the minimal conductivity and the Schwinger mechanismMar 01 2014Jul 04 2014We propose a model for the electric current in graphene in which electric carriers are supplied by virtual particles allowed by the uncertainty relations. The process to make a virtual particle real is described by a weak value of a group velocity: the ... More
Compressibility of Mixed-State SignalsMar 22 2001We present a formula that determines the optimal number of qubits per message that allows asymptotically faithful compression of the quantum information carried by an ensemble of mixed states. The set of mixed states determines a decomposition of the ... More
What is Possible Without Disturbing Partially Known Quantum States?Jan 31 2001Jan 17 2002Consider a situation in which a quantum system is secretly prepared in a state chosen from the known set of states. We present a principle that gives a definite distinction between the operations that preserve the states of the system and those that disturb ... More
Regular and Black Hole Solutions in the Einstein-Skyrme Theory with Negative Cosmological ConstantMar 31 2005Jul 19 2005We study spherically symmetric regular and black hole solutions in the Einstein-Skyrme theory with a negative cosmological constant. The Skyrme field configuration depends on the value of the cosmological constant in a similar manner to effectively varying ... More
B=3 Tetrahedrally Symmetric Solitons in the Chiral Quark Soliton ModelApr 17 2002In this paper, B=3 soliton solutions with tetrahedral symmetry are obtained numerically in the chiral quark soliton model using the rational map ansatz. The solution exhibits a triply degenerate bound spectrum of the quark orbits in the background of ... More
On the Chemical Potential of D-instantons in c=0 Noncritical String TheoryMar 25 2005We study the chemical potential of D-instantons in c=0 noncritical string theory. In a recent work(hep-th/0405076), it was shown that the chemical potential can be calculated using the one matrix model. The calculation was done using the method of orthogonal ... More
General Relativistic Electromagnetism and Particle Acceleration in Pulsar Polar CapJun 28 2002Oct 16 2002We reconstruct a 3+1 formalism of general relativistic electromagnetism, and derive the equations of motion of charged particles in the pulsar magnetosphere, taking account of the inclination between the rotation axis and the magnetic axis. Apart from ... More
Multiloop Amplitudes of Light-cone Gauge Bosonic String Field Theory in Noncritical DimensionsJul 23 2013Jul 29 2013We study the multiloop amplitudes of the light-cone gauge closed bosonic string field theory for $d \neq 26$. We show that the amplitudes can be recast into a BRST invariant form by adding a nonstandard worldsheet theory for the longitudinal variables ... More
A Background Independent Formulation of Noncritical String TheoryMar 22 1995Using the string field theory recently proposed by the authors and collaborators, we give a background independent formulation of rational noncritical string theories with $c\leq 1$. With a little modification of the string field Hamiltonians previously ... More
Biological dose representation for carbon-ion radiotherapy of unconventional fractionationJul 05 2016In carbon-ion radiotherapy, single-beam delivery each day in alternate directions has been commonly practiced for operational efficiency, taking advantage of the Bragg peak and the relative biological effectiveness (RBE) for uniform dose conformation ... More
Long-range Coulomb interaction effects on the surface Dirac electron system of a three-dimensional topological insulatorDec 02 2014The surface state of a three-dimensional topological insulator forms a two-dimensional massless Dirac electron system. In Dirac electron systems, Coulomb interaction is not screened due to the small density of states at the Fermi energy and thus the long-range ... More
Underlying mechanism of numerical instability in large eddy simulation of turbulent flowsFeb 05 2004Apr 13 2004This paper extends our recent theoretical work concerning the feasibility of stable and accurate computation of turbulence using a large eddy simulation [Ida and Taniguchi, Phys. Rev. E 68, 036705 (2003)]. In our previous paper, it was shown, based on ... More
Gauged Q-balls in the Affleck-Dine mechanismJan 06 2014We consider gauged Q-balls in the gravity-mediation-type model in the Affleck-Dine mechanism, which is described by the potential $V_{\rm grav.}(\phi):=(m_{\rm grav.}^2/2)\phi^2\left[1+K\ln(\phi/M)^2\right]$ with $K<0$. In many models of gauged Q-balls, ... More
Gravitating Q-balls in the Affleck-Dine mechanismMay 19 2011We investigate how gravity affects "Q-balls" with the Affleck-Dine potential $V_{AD}(\phi):=\frac{m^2}{2}\phi^2[ 1+K\ln (\frac{\phi}{M})^2]$. Contrary to the flat case, in which equilibrium solutions exist only if $K<0$, we find three types of gravitating ... 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
Microscopic derivation of magnon spin current in topological insulator/ferromagnet heterostructureOct 12 2016We investigate a spin-electricity conversion effect in a topological insulator/ferromagnet heterostructure. In the spin-momentum-locked surface state, an electric current generates non-equilibrium spin accumulation, which causes a spin-orbit torque that ... More
Localizing modes of massive fermions and a U(1) gauge field in the inflating baby-skyrmion branesDec 12 2011Apr 12 2012We consider the six dimensional brane world model, where the brane is described by a localized solution to the baby-Skyrme model extending in the extradimensions. The branes have a cosmological constant modeled by inflating four dimensional slices and ... More
Axially Symmetric Black Hole SkyrmionsJul 29 2003It has been known that a B=2 skyrmion is axially symmetric. We consider the Skyrme model coupled to gravity and obtain static axially symmetric black hole solutions numerically. The black hole skyrmion no longer has integer baryonic charge but has fractional ... More
Peculiar Velocities of Nonlinear Structure: Voids in McVittie SpacetimeSep 10 1999Dec 07 1999As a study of peculiar velocities of nonlinear structure, we analyze the model of a relativistic thin-shell void in the expanding universe. (1) Adopting McVittie (MV) spacetime as a background universe, we investigate the dynamics of an uncompensated ... More
Operator ordering in Two-dimensional N=1 supersymmetry with curved manifoldAug 21 2007We investigate an operator ordering problem in two-dimensional N=1 supersymmetric model which consists of n real superfields. There arises an operator ordering problem when the target space is curved. We have to fix the ordering in quantum operator properly ... More
Perturbative dynamics of matrix string for the membraneJan 29 2004Apr 14 2004Recently Sekino and Yoneya proposed a way to regularize the world volume theory of membranes wrapped around $S^1$ by matrices and showed that one obtains matrix string theory as a regularization of such a theory. We show that this correspondence between ... More
Soliton Solutions in Noncritical String Field Theory?Jun 20 1996We look for soliton solutions in $c=0$ noncritical string field theory constructed by the authors and collaborators. It is shown that the string field action itself is very complicated in our formalism but it satisfies a very simple equation. We derive ... More
Exact, molecular-shaped vortices with fractional and integer charges in the extended Skyrme-Faddeev modelSep 23 2013Dec 19 2014We analytically construct vortex solutions in the integrable sector of the extended Skyrme-Faddeev model. The solutions are holomorphic type which satisfy the zero curvature condition. For the model parameter $\beta e^2=1$ there is a lump solution, and ... More
Multi-soliton solutions in the chiral quark soliton modelMay 28 2004In this article a series of solutions with higher baryon numbers in the chiral quark soliton model are reported. The chiral quark soliton model is a simple quark model that incorporates the basic features of QCD. The B=2 axially symmetric soliton solution ... More
Degeneracy of the quarks, shell structure in the chiral solitonFeb 09 2004We obtain multi-soliton solutions with discrete symmetries in the chiral quark soliton model using the rational map ansatz. The solutions exhibit degenerate bound spectra of the quark orbits depending on the background of pion field configurations. It ... More
Black Holes with Skyrme HairJan 09 2005This paper is intended to give a review of the recent developments on black holes with Skyrme hair. The Einstein-Skyrme system is known to possess black hole solutions with Skyrme hair. The spherically symmetric black hole skyrmion with B=1 was the first ... More
Unconventional Spin Hall Effect and Axial Current Generation in a Dirac SemimetalFeb 03 2016May 30 2016We investigate electrical transport in a three-dimensional massless Dirac fermion model that describes a Dirac semimetal state realized in topological materials. We derive a set of interdependent diffusion equations with eight local degrees of freedom, ... More
Orbital Order Effect of Two-Dimensional Spin Gap System for CaV4O9Dec 04 1997Dec 07 1997Effects of possible orbital order in magnetic properties of two-dimensional spin gap system for CaV$_4$O$_9$ are investigated theoretically. After analyzing experimental data, we show that single orbital models assumed in the literature are insufficient ... More
Operator ordering and Classical soliton path in Two-dimensional N=2 supersymmetry with Kahler potentialAug 03 2005Oct 25 2005We investigate a 2-dimensional N=2 supersymmetric model which consists of n chiral superfields with Kahler potential. When we define quantum observables, we are always plagued by operator ordering problem. Among various ways to fix the operator order, ... More
Stability and Convergence of an Upwind Finite Difference Scheme for the Radiative Transport EquationMar 26 2013An explicit numerical scheme is proposed for solving the initial-boundary value problem for the radiative transport equation in a rectangular domain with completely absorbing boundary condition. An upwind finite difference approximation is applied to ... More
Maxwell boundary conditions imply non-Lindblad master equationMar 02 2016Aug 12 2016From the Hamiltonian connecting the inside and outside of an Fabry-Perot cavity, which is derived from the Maxwell boundary conditions at a mirror of the cavity, a master equation of a non-Lindblad form is derived when the cavity embeds matters, although ... More
Langlands correspondence for isocrystals and existence of crystalline companion for curvesOct 02 2013Apr 27 2016In this paper, we show the Langlands correspondence for isocrystals on curves. This shows the existence of crystalline companion in the curve case. For the proof, we construct the theory of arithmetic $\mathscr{D}$-modules for algebraic stacks whose diagonal ... More
Linear Collider Physics Resource Book for Snowmass 2001 - Part 1: IntroductionJun 13 2001This Resource Book reviews the physics opportunities of a next-generation e+e- linear collider and discusses options for the experimental program. Part 1 contains the table of contents and introduction and gives a summary of the case for a 500 GeV linear ... More
A study of topological vertexing for heavy quark taggingFeb 09 2001We compare heavy quark tagging and anti-tagging efficiencies for vertex detectors with different inner raddi using the topological vertex technique developed at the SLC/SLD experiment. Charm tagging benefits by going to very small inner radii.
Measurement of the Angle $φ_1(β)$ and $B \bar B$ Mixing (Recent Results from BaBar and Belle)Aug 29 2003Recent results from BaBar and Belle experiments on $B \bar B$ mixing and $\sin 2\phi_1$ are presented. Accuracy of $\Delta m_d$ measurements has reached 1.2%. Higher order effects within the Standard Model or possible new physics effect that might appear ... More
Observation of Cabibbo suppressed $B \to D^{(*)}K^-$ decays at BelleApr 28 2001Cabibbo-suppressed decays $B \to D^{(*)} K^-$ using a 10.4 fb$^{-1}$ data sample accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+ e^-$ storage ring. The high-momentum particle identification system of Belle is used ... More
Time Dependent B0s - B0s-bar Mixing Using Inclusive and Semileptonic B Decays at SLDDec 19 2000We set a preliminary 95% C.L. exclusion on the oscillation frequency of B0s - B0s-bar mixing using a sample of 400,000 hadronic Z0 decays collected by the SLD experiment at the SLC between 1996 and 1998. The analyses determine the b-hadron flavor at production ... More
A study of the orientation and energy partition of three-jet events in hadronic Z0 decaysAug 28 1996We have measured the distributions of the jet energies in e+e- --> qq^bar g events, and of the three orientation angles of the event plane, using hadronic $Z^0$ decays collected in the SLD experiment at SLAC. We find that the data are well described by ... More
Measurement of the Charged Multiplicities in b, c and Light Quark Events from Z0 DecaysAug 14 1996Average charged multiplicities have been measured separately in $b$, $c$ and light quark ($u,d,s$) events from $Z^0$ decays measured in the SLD experiment. Impact parameters of charged tracks were used to select enriched samples of $b$ and light quark ... More
Measurement of alpha_s(M_Z^2) from Hadronic Event Observables at the Z^0 ResonanceJan 06 1995Jul 23 1997The strong coupling alpha_s(M_Z^2) has been measured using hadronic decays of Z^0 bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O(alpha_s^2), and including resummed analytic formulae based ... More
On estimates for the Stokes flow in a space of bounded functionsJun 20 2014Apr 21 2016In this paper, we study regularizing effects of the composition operator $S(t)\mathbb{P}\partial$ for the Stokes semigroup $S(t)$ and the Helmholtz projection $\mathbb{P}$ in a space of bounded functions. We establish new a priori $L^{\infty}$-estimates ... More
Measurement of Polarization and Triple-Product Correlations in B -> phi K^* DecaysAug 27 2004We present a measurement of the decay amplitudes and triple-product correlations in B -> phi K^* decays based on 140 fb^-1 of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e^+ e^- storage ring. The decay amplitudes for ... More
Measurement of Branching Fraction for B --> psi(2S)K*(892) DecaysAug 15 2003We have measured the branching fractions of the colour suppressed decays B^{+} --> \psi(2S) K^{*+}(892) and B^{0} --> psi(2S)K^{*0}(892) using a data sample of 84 million B\bar{B} events recorded by the Belle detector on the Upsilon(4S) resonance. The ... More
Observation of the Decay $B \to K \ell^{+} \ell^{-}$Sep 18 2001Oct 19 2001We report a search for the flavor-changing neutral current decay $B \to K^{(*)} \ell^{+} \ell^{-}$ using a 29.1 fb${}^{-1}$ data sample accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^{+}e^{-}$ storage ring. We observe ... More
Measurement of B0d - B0d-bar mixing rate from the time evolution of dilepton events at the Upsilon(4S)Nov 28 2000Mar 14 2001We report a determination of the B0d - B0d-bar mixing parameter Delta-m_d based on the time evolution of dilepton yields in Upsilon(4S) decays. The measurement is based on a 5.9 /fb data sample collected by the Belle detector at KEKB. The proper-time ... More
C_2-cofiniteness of the 2-cycle permutation orbifold models of minimal Virasoro vertex operator algebrasMay 11 2010Feb 25 2011In this article, we give a sufficient and necessary condition for the $C_2$-cofiniteness of the 2-cycle permutation orbifold model $(V\otimes V)^\sigma$ for a $C_2$-cofinite vertex operator algebra and the 2-cycle permutation $\sigma$ of $V\otimes V$. ... More
Involutions on pro-$p$-Iwahori Hecke algebrasApr 03 2017The pro-$p$-Iwahori Hecke algebra has an involution $\iota$ defined in terms of Iwahori-Matsumoto basis. Then for a module $\pi$ of pro-$p$-Iwahori Hecke, $\pi^\iota = \pi\circ \iota$ is also a module. We calculate $\pi^\iota$ for simple modules $\pi$. ... More
Parabolic inductions for pro-$p$-Iwahori Hecke algebrasDec 05 2016We give some properties of parabolic inductions and their adjoint functors for pro-$p$-Iwahori Hecke algebras.
Invariants of Fokker-Planck equationsJul 19 2016A weak invariant of a stochastic system is defined in such a way that its expectation value with respect to the distribution function as a solution of the associated Fokker-Planck equation is constant in time. A general formula is given for time evolution ... More
Young diagrams and intersection numbers for toric manifolds associated with Weyl chambersApr 15 2014Jan 12 2015We study intersection numbers of invariant divisors in the toric manifold associated with the fan determined by the collection of Weyl chambers for each root system of classical type and of exceptional type $G_2$. We give a combinatorial formula for intersection ... More
Spontaneous and dynamical symmetry breaking in higher-dimensional space-time with boundary termsJul 01 2003In this thesis we study physics beyond the standard model focusing on the quantum field theory in higher-dimensional space-time with some boundary terms. The boundary term causes nontrivial consequences about the vacuum structure of the higher-dimensional ... More
Attractive Central Potential in the SU(3) Skyrme ModelOct 25 1997The interaction between the hyperon and the nucleon is investigated in the SU(3) Skyrme model. The static potential, which is expanded in terms of the modified SU(3) rotation matrices, is obtained for several orientations with the Atiyah-Manton ansatz. ... More
Measurement of the b-quark fragmentation function in Z0 decaysFeb 14 2002We present a measurement of the b-quark inclusive fragmentation function in Z0 decays using a novel kinematic B-hadron energy reconstruction technique. The measurement was performed using 350,000 hadronic Z0 events recorded in the SLD experiment at SLAC ... More
Measurement of the Branching Fraction for B->eta' K and Search for B->eta'pi+Aug 06 2001We report measurements for two-body charmless B decays with an eta' meson in the final state. Using 11.1X10^6 BBbar pairs collected with the Belle detector, we find BF(B^+ ->eta'K^+)=(79^+12_-11 +-9)x10^-6 and BF(B^0 -> eta'K^0)=(55^+19_-16 +-8)x10^-6, ... More
Measurement of alpha-s from energy-energy correlations at the Z0 resonanceMay 17 1994May 18 1994We have determined the strong coupling alpha-s from a comprehensive study of energy-energy correlations (EEC) and their asymmetry (AEEC) in hadronic decays of Z0 bosons collected by the SLD experiment at SLAC. The data were compared with all four available ... More
Exterior Navier-Stokes flows for bounded dataJun 16 2016We prove unique existence of mild solutions on $L^{\infty}_{\sigma}$ for the Navier-Stokes equations in an exterior domain in $ \mathbb{R}^{n}$, $n\geq 2$, subject to the non-slip boundary condition.
Measurement of the D0 - anti-D0 lifetime difference using D0 -> Kpi/KK decaysAug 15 2003Sep 03 2003We report a preliminary measurement of the D0-anti-D0 mixing parameter y_CP and the CP-violating parameter A_G using the decay D*+ -> D0 pi+ followed by D0 -> K- pi+ and D0 -> K+ K-. The results are obtained from a 158 fb^-1 data sample collected near ... More
Search for time-dependent B0s - B0s-bar oscillations using a vertex charge dipole techniqueSep 01 2002Jan 03 2003We report a search for B0s - B0s-bar oscillations using a sample of 400,000 hadronic Z0 decays collected by the SLD experiment. The analysis takes advantage of the electron beam polarization as well as information from the hemisphere opposite that of ... More
A TEST OF THE FLAVOR INDEPENDENCE \\[.1in] OF STRONG INTERACTIONSJan 13 1995Jan 18 1995We present a comparison of the strong couplings of light ($u$,~$d$,~and~$s$), $c$, and $b$ quarks determined from multijet rates in flavor-tagged samples of hadronic $Z^0$ decays recorded with the SLC Large Detector at the SLAC Linear Collider. Flavor ... More
Analytic study of singular curvesSep 15 2016Nov 28 2016We study singular curves from analytic point of view. We give completely analytic proofs for the Serre duality and a generalized Abel's theorem. We also reconsider Picard varieties, Albanese varieties and generalized Jacobi varieties of singular curves ... More
Holonomies of gauge fields in twistor space 4: functional MHV rules and one-loop amplitudesMay 31 2011We consider generalization of the Cachazo-Svrcek-Witten (CSW) rules to one-loop amplitudes of N=4 super Yang-Mills theory in a recently developed holonomy formalism in twistor space. We first reconsider off-shell continuation of the Lorentz-invariant ... More
An interpretation of multigraviton amplitudesApr 20 2005We obtain alternative expressions for the multigraviton tree level amplitudes and discuss their general properties. In particular, by analogy with Yang-Mills theory, we find that some combinatoric structure can be carried by a Chan-Paton factor of general ... More
Second order term of cover time for planar simple random walkSep 24 2017Jun 02 2018We consider the cover time for a simple random walk on the two-dimensional discrete torus of side length $n$. Dembo, Peres, Rosen, and Zeitouni [Ann. Math. 160:433-464, 2004] identified the leading term in the asymptotics for the cover time as $n$ goes ... More
Geometrically simple quasi-abelian varietiesJun 30 2017Nov 27 2017We define the geometric simpleness for toroidal groups. We give an example of quasi-abelian variety which is geometrically simple, but not simple. We show that any quasi-abelian variety is isogenous to a product of geometrically simple quasi-abelian varieties. ... More
On the deconfining limit in (2+1)-dimensional Yang-Mills theoryApr 19 2008Nov 30 2009We consider (2+1)-dimensional Yang-Mills theory on $S^1 \times S^1 \times {\bf R}$ in the framework of a Hamiltonian approach developed by Karabali, Kim and Nair. The deconfining limit in the theory can be discussed in terms of one of the $S^1$ radii ... More
$C_2$-cofiniteness of 2-cyclic permutation orbifold modelsJul 14 2011Sep 15 2011In this article, we consider permutation orbifold models of $C_2$-cofinite vertex operator algebras of CFT type. We show the $C_2$-cofiniteness of the 2-cyclic permutation orbifold model $(V\otimes V)^{S_2}$ for an arbitrary $C_2$-cofinite simple vertex ... More
Tilting modules arising from two-term tilting complexesApr 04 2011Jun 30 2011We show that every two-term tilting complex over an Artin algebra has a tilting module over a certain factor algebra as a homology group. Also, we determine the endomorphism algebra of such a homology group, which is given as a certain factor algebra ... More
Reflections and torsion theories for selfinjective algebrasMay 24 2010Nov 05 2015We introduce the notion of reflections for selfinjective algebras from the point of view of torsion theories induced by two-term tilting complexes. As an application, we determine the transformations of Brauer trees associated with reflections. In particular, ... More
On the conjecture of Athanasiadis related to freeness of a family of hyparplane arrangementsOct 03 2011Oct 17 2011We prove a characterization of freeness, conjectured by Athanasiadis, for the family of hyperplane arrangements which lie between the Coxeter and the Catalan arrangement of type $A_\ell$. One direction was already proved in [2]. Here we prove the other ... More
Exponents of 2-multiarrangements and freeness of 3-arrangementsMay 28 2010We give the upper bound of differences of exponents for balanced 2-multiarrangements in terms of the cardinality of hyperplanes. Also, we give a shift isomorphism of 2-multiarrangements like Coxeter arrangements when the difference of exponents is maximum. ... More
Addition-deletion theorem for free hyperplane arrangements and combinatoricsNov 09 2018In the theory of hyperplane arrangements, the most important and difficult problem is the combinatorial dependency of several properties. In this atricle, we prove that Terao's celebrated addition-deletion theorem for free arrangements is combinatorial, ... More
Deletion theorem and combinatorics of hyperplane arrangementsSep 18 2017Sep 23 2017We show that the deletion theorem of a free arrangement is combinatorial, i.e., whether we can delete a hyperplane from a free arrangement keeping freeness depends only on the intersection lattice. In fact, we give an explicit sufficient and necessary ... More
Plus-one generated and next to free arrangements of hyperplanesAug 14 2018Aug 17 2018We introduce a new class of arrangements of hyperplanes, called (strictly) plus-one generated arrangements, from algebraic point of view. Plus-one generatedness is close to freeness, i.e., plus-one generated arrangements have their logarithmic derivation ... More
Restrictions of free arrangements and the division theoremMar 12 2016This is a survey and research note on the modified Orlik conjecture derived from the division theorem introduced in [2]. The division theorem is a generalization of classical addition-deletion theorems for free arrangements. The division theorem can be ... More
Extremes of local times for simple random walks on symmetric treesMar 30 2016Mar 07 2017We consider local times of the simple random walk on the $b$-ary tree of depth $n$ and study a point process which encodes the location of the vertex with the maximal local time and the properly centered maximum over leaves of each subtree of depth $r_n$ ... More
Patterns of supersymmetry breaking in moduli-mixing racetrack modelOct 27 2006We show some structures of moduli stabilization and supersymmetry breaking caused by gaugino condensations with the gauge couplings depending on two moduli which often appear in the four-dimensional effective theories of superstring compactifications. ... More
Divisionally free arrangements of hyperplanesFeb 26 2015Apr 01 2015We consider the triple $(\mathcal{A},\mathcal{A}',\mathcal{A}^H)$ of hyperplane arrangements and the division of their characteristic polynomials. We show that the freeness of $\mathcal{A}^H$ and the division of $\chi(\mathcal{A};t)$ by $\chi(\mathcal{A}^H;t)$ ... More
Rationality of the vertex operator algebra $V_L^+$ for a positive definite even lattice $L$Nov 13 2003The lattice vertex operator algebra $V_L$ associated to a positive definite even lattice $L$ has an automorphism of order 2 lifted from -1-isometry of $L$. We prove that for the fixed point vertex operator algebra $V_L^+$, any $\Z_{\geq0}$-graded weak ... More
Fusion rules for the free bosonic orbifold vertex operator algebraJul 20 1999Fusion rules among irreducible modules of the free bosonic orbifold vertex operator algebra are completely determined.
Does gravitational wave propagate in the five dimensional space-time with Kaluza-Klein monopole?Jan 30 1995The behavior of small perturbations around the Kaluza-Klein monopole in the five dimensional space-time is investigated. The fact that the odd parity gravitational wave does not propagate in the five dimensional space-time with Kaluza-Klein monopole is ... More
Gauge field and geometric control of quantum-thermodynamic engineSep 14 2011The problem of extracting the work from a quantum-thermodynamic system driven by slowly varying external parameters is discussed. It is shown that there naturally emerges a gauge-theoretic structure. The field strength identically vanishes if the system ... More
Reply to the Comment by B. AndresenDec 06 2010All the comments made by Andresen's comments are replied and are shown not to be pertinent. The original discussions [ABE S., Europhys. Lett. 90 (2010) 50004] about the absence of nonextensive statistical mechanics with q-entropies for classical continuous ... More
Time evolution of Renyi entropy under the Lindblad equationJul 20 2016Aug 04 2016In recent years, the Renyi entropy has repeatedly been discussed for characterization of quantum critical states and entanglement. Here, time evolution of the Renyi entropy is studied. A compact general formula is presented for the lower bound on the ... More
Invariants of Fokker-Planck equationsJul 19 2016Mar 18 2017A weak invariant of a stochastic system is defined in such a way that its expectation value with respect to the distribution function as a solution of the associated Fokker-Planck equation is constant in time. A general formula is given for time evolution ... More
Reply to Comments on "Stability of Tsallis antropy and instabilities of Renyi and normalized Tsallis entropies: A basis for q-exponential distributions"Dec 31 2004Bashkirov's comments (cond-mat/0410667) on the paper [S. Abe, Phys. Rev. E 66, 046134 (2002)] are all refuted. In addition, it is discussed that the Renyi entropy is irrelevant to generalization of Boltzmann-Gibbs statistical mechanics for complex systems. ... More
Geometry of escort distributionsMay 11 2003Given an original distribution, its statistical and probabilistic attributs may be scanned by the associated escort distribution introduced by Beck and Schlogl and employed in the formulation of nonextensive statistical mechanics. Here, the geometric ... More
Generalized entropy optimized by an arbitrary distributionNov 20 2002We construct the generalized entropy optimized by a given arbitrary statistical distribution with a finite linear expectation value of a random quantity of interest. This offers, via the maximum entropy principle, a unified basis for a great variety of ... More
General pseudoadditivity of composable entropy prescribed by existence of equilibriumDec 12 2000The concept of composability states that entropy of the total system composed of independent subsystems is a function of entropies of the subsystems. Here, the most general pseudoadditivity rule for composable entropy is derived based only on existence ... More
Heat and generalized Clausius entropy of nonextensive systemsDec 07 2000Jan 06 2001Macroscopic nonextensive thermodynamics is studied without recourse to microscopic statistical mechanics. It is shown that if entropy is nonextensive, the concept of physical temperature introduced through the generalized zeroth law of thermodynamics ... More