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Analytic Methods in Open String Field Theory

We review the basics of recent developments of analytic methods in open string field theory. We in particular explain Schnabl's analytic solution for tachyon condensation in detail, assuming only the basic knowledge on conformal field theory.

Subbarrier Fusion Reactions and Many-Particle Quantum Tunneling

Low-energy heavy-ion fusion reactions are governed by quantum tunneling through the Coulomb barrier formed by the strong cancellation of the repulsive Coulomb force with the attractive nuclear interaction between the colliding nuclei. Extensive experimental as well as theoretical studies have revealed that fusion reactions are strongly influenced by couplings of the relative motion ...

Quaternionic Variational Formalism for General Relativity in Riemann and Riemann-Cartan Space-Times

It is shown that there exists a 2-dimensional matrix representation of complex quaternions over real quaternions, which allows to define Pauli matrix in 4 dimensions over the quaternionic field and leads to the quaternionic spinor group previously proposed. It is also attempted to apply complex quaternions to general relativity at the level of the variational formalism. Linear ...

Synchronization Thresholds of Coupled Self-Excited Nonidentical Pendula Suspended on the Vertically Displacing Beam

The synchronization of a number of self-excited nonidentical pendula (with the same masses and different lengths) hanging on the same beam which can move vertically has been investigated. We identify different synchronous configurations and investigate their stability. An approximate analytical analysis of the energy balance allows to derive the synchronization conditions, phase ...

Confinement and Dynamical Symmetry Breaking in Non-SUSY Gauge Theory from S-Duality in String Theory

We discuss an attempt to understand confinement and dynamical symmetry breaking in a 4-dimensional non-supersymmetric gauge theory using S-duality in type IIB string theory. The electric theory is a USp(2n) gauge theory and its magnetic dual is argued to be an SO(2n) or SO(2n-1) gauge theory. These theories are obtained as the low-energy effective theory of O3-D̅3̅ systems in type ...

Analytical Calculation on Critical Magnetic Field in Holographic Superconductors with Backreaction

We investigate the effect of spacetime backreaction on the upper critical magnetic field for s-wave holographic superconductors by using the matching method. The backreaction of the constant external magnetic field and the electric field to the background geometry leads to a dyonic black hole solution. The magnetic fields as well as the electric fields acting as gravitational ...

Mass Insertion Formula for Chargino Contribution to ΔB = 1 Wilson Coefficients and Its Application to CP Asymmetries of B → Kπ

The comprehensive mass insertion formula of the b → sq̅q transitions was provided for the chargino contributions. The method clarifies physics behind the calculations of the supersymmetric contributions to FCNCs. The result was applied to the analysis of the difference of the CP asymmetries of the B → Kπ decays. It is shown that the supersymmetry is not responsible for the ...

Toward an Understanding of Short Distance Repulsions among Baryons in QCD: NBS Wave Functions and Operator Product Expansion

We report on our recent attempts to determine the short distance behaviors of general 2- baryon and 3-baryon forces, which are defined from the Nambu-Bethe-Salpeter (NBS) wave function, by using the operator product expansion and a renormalization group analysis in QCD. We have found that the repulsion at short distance increases as the number of valence quarks increases or when ...

Level Spacings of Parametric Chiral Random Matrices and Two-Color QCD with Twisted Boundary Condition

We evaluate the level spacing and smallest eigenvalue distributions of chiral random matrix ensembles transiting from symplectic or orthogonal to unitary symmetry classes with a crossover parameter ρ. As expected from the effective σ model description, these results can be fitted perfectly to the fundamental or adjoint staggered Dirac spectrum of SU(2) quenched lattice gauge theory ...

Suppressing Proton Decay by Cancellation in S4 Flavor Symmetric Extra U(1) Model

We consider proton stability based on E6 inspired extra U(1) model with S4 flavor symmetry. In this model, a long life time of proton is realized by the flavor symmetry. One of the interesting effects of flavor symmetry is that the proton decay widths of p → µ+X are suppressed by cancellation. This suppression mechanism is important in the case that Yukawa coupling constants are ...

Extrinsic Spin Hall Effect Due to Transition-Metal Impurities

We investigate the extrinsic spin Hall effect in the electron gas model due to transition-metal impurities based on the single-impurity Anderson model with orbital degrees of freedom. Both the skew scattering and side jump mechanisms are analyzed in a unified way, and the significant role of orbital degrees of freedom are clarified. The obtained spin Hall conductivities are in ...

Spinless Basis for Spin-Singlet FQH States

We investigate an alternative description of the SU(M)-singlet FQH state by using the spinless basis. The SU(M)-singlet Halperin state is obtained via the q-deformation of the Laughlin state and its root of unity limit, by applying the Yangian Gelfand-Zetlin basis for the spin Calogero-Sutherland model. The squeezing rule for the SU(M) state is also investigated in terms of the ...

New Period-Doubling and Equiperiod Bifurcations of the Reversible Area-Preserving Map

Two types of period-doubling and equiperiod bifurcations of the reversible area-preserving map are studied. Ordinary period-doubling bifurcation means that the eigenvalue of the mother elliptic periodic orbit (u) is −1, u becomes a saddle periodic orbit with reflection, and an elliptic daughter periodic orbit (v) appears, where the period of v is twice that of u. The other ...

On Static Charged Black Holes in Type IIA on a Nearly-Kähler Coset

We study static, spherically symmetric black hole solutions in four-dimensional N = 2 gauged supergravity with one vector multiplet and one hyper-tensor multiplet. This is derived from massive type IIA theory compactified on the nearly-Kähler coset space G2/SU(3). It is well known that the Romans' mass parameter yields the Stückelberg-type deformation of the gauge field strengths ...

Exponential Fall-Off Behavior of Regge Scatterings in Compactified Open String Theory

We calculate massive string scattering amplitudes of compactified open string in the Regge regime. We extract the complete infinite ratios among high-energy amplitudes of different string states in the fixed angle regime from these Regge string scattering amplitudes. The complete ratios calculated by this indirect method include and extend the subset of ratios calculated previously ...

Massive Modes in Magnetized Brane Models

We study higher dimensional models with magnetic fluxes, which can be derived from superstring theory. We study mass spectrum and wavefunctions of massless and massive modes for spinor, scalar and vector fields. We compute the 3-point couplings and higher order couplings among massless modes and massive modes in 4D low-energy effective field theory. These couplings have non-trivial ...

Separation of Chiral and Deconfinement Phase Transitions in Curved Space-Time

We calculated the chiral condensate and the dressed Polyakov loop in the space-time R×S3 and R×H3. The chiral condensate is the order parameter for the chiral phase transition, whereas the dressed Polyakov loop is the order parameter for the deconfinement phase transition. When there is a current mass, critical points for the chiral and deconfinement phase transitions are different ...

Quark-Anti-Quark Potentials from Nambu-Bethe-Salpeter Amplitudes on Lattice

Quark–anti-quark (q̅-q) potentials with finite quark masses are studied from the q̅-q Nambu-Bethe-Salpeter (NBS) wave functions in quenched lattice QCD. With the use of a method which has been recently developed in the derivation of nuclear forces from lattice QCD, we derive the q̅-q potentials from the NBS wave functions. We calculate the q̅-q NBS wave functions in pseudo-scalar ...

Application of Fixed Scale Approach to Static Quark Free Energies in Quenched and 2 + 1 Flavor Lattice QCD with Improved Wilson Quark Action

The free energies of static quarks and the Debye screening masses in the quark gluon plasma are studied using Polyakov-line correlation functions in lattice QCD adopting the fixed-scale approach in which temperature is varied without changing the spatial volume and the renormalization factors.We calculate static-quark free energies in various color channels in the high temperature ...

Gravitational Waves from a Particle in Circular Orbits around a Schwarzschild Black Hole to the 22nd Post-Newtonian Order

We extend our previous results of the 14th post-Newtonian (PN) order expansion of gravitational waves for a test particle in circular orbits around a Schwarzschild black hole to the 22PN order, i.e. v44 beyond the leading Newtonian approximation where v is the orbital velocity of a test particle. Comparing our 22PN formula for the energy flux with high precision numerical results, ...