119400472
One loop QCD correction for inclusive jet production and Drell-Yan process in composite models
We calculate the one-loop QCD correction for inclusive jet cross sections and Drell-Yan process in a general low-energy effective Lagrangian for composite quarks and leptons. {copyright} {ital 1997} {ital The American Physical Society}
119660786
Baryon number violation in dense matter. On the relation with anomalous high energy scattering
Abstract The recent claim of the equivalence of baryon number violation in dense matter and that of high energy scattering is examined. We present a plausible argument against the claim. We also calculate the anomalous decay rate of dense matter to (μ/E 0 ) 8 3 In (μ/E 0 ) order. To this order, we find the anomalous decay rate is completely equivalent to the anomalous cross section of the high energy scattering calculated by the valley method.
3172088
RAPIDITY GAP OF WEAKLY COUPLED LEPTOQUARK PRODUCTION IN ep COLLIDER
We show that the current bounds on the leptoquark couplings imply that if leptoquarks are produced in ep collisions, a significant fraction of them could form a leptoquark–quark bound state. The decay of the bound state has a distinct event shape with rapidity gap. A possible application of this observation in the leptoquark search at HERA is discussed.
119272116
Light bending by nonlinear electrodynamics under strong electric and magnetic field
We calculate the bending angles of light under the strong electric and magnetic fields by a charged black hole and a magnetized neutron star according to the nonlinear electrodynamics of Euler-Heisenberg interaction. The bending angle of light by the electric field of charged black hole is computed from geometric optics and a general formula is derived for light bending valid for any orientation of the magnetic dipole. The astronomical significance of the light bending by magnetic field of a neutron star is discussed.
14559352
Estimating higher order perturbative coefficients using Borel transform
A new method of estimating higher order perturbative coefficients is discussed. It exploits the rapid, asymptotic growth of perturbative coefficients and the information on the singularities in the complex Borel plane. A comparison with other methods is made in several Quantum Chromodynamics (QCD) expansions.
16719442
Chiral vacuum alignment in dense QCD
Abstract We discuss an interesting possibility of nontrivial, quark-mass induced chiral vacuum alignment in color–flavor locking phase of cold, dense QCD. With the simplifying assumption that the gaps for quarks are identical to those of antiquarks and the light quark masses are given by m u = m d and m s / m d =15, we find the true chiral vacuum can align only to one of the discrete number of directions in the continuum of chiral vacua. The alignment depends on the size of the diquark condensates, and the vacuum transitions between the discrete vacua caused by the evolution of the diquark condensates can be first order phase transition with vanishing or nonvanishing latent heat, depending on the vacua involved. It is also shown that as μ →∞, where μ is the baryon chemical potential, parity is spontaneously broken through the vacuum alignment.
15345099
Colliding Waves on a Brane, the Big Bounce and Reconnection
We present a time-dependent solution of the Nambu-Goto action which represents two colliding waves moving at the speed of light. This solution can be decomposed into two distinct regions with different geometries corresponding to shrinking or expanding brane universe and two colliding branes. The former describes the Big Bounce without singularity while the latter describes that two branes collide and reconnect to each other. The colliding brane region has a signature change. Classical dynamics of a massive particle on the brane is studied through the geodesics.
119342247
Noncommutative Dirac–Born–Infeld action for D-brane
Abstract We derive the noncommutative Dirac–Born–Infeld action for the D -brane, which governs dynamics of D -brane with a NS-NS B -field in the low energy regime. Depending on some details of the path integral prescriptions, both ordinary Dirac–Born–Infeld action and noncommutative one can be obtained by evaluating the same Polyakov string path integral for the open string ending on the D -brane. Thus, it establishes the equivalence of the noncommutative Dirac–Born–Infeld action and the ordinary one.
119371484
Open Superstring and Noncommutative Geometry
We perform canonical quantization of the open Neveu-Schwarz-Ramond (NSR) superstrings in the background of a D-brane with the NS B-field. If we choose the mixed boundary condition as a primary constraint, it generates a set of secondary constraints. These constraints are easily solved and as a result, the noncommutative geometry in the bosonic string theory is extended to the superspace. Solving the constraint conditions we also find that the Hamiltonian for the superstring is equivalent to a free superstring Hamiltonian on the target space with the effective open string metric G.
121311744
Polarization of recoil-electron beam in high-energy Moller and Bhabha scattering
Longitudinal and transverse polarizations of the final electron beam in Moller and Bhabha scattering are analyzed in electroweak gauge models involving more than one neutral vector boson. In pure QED, for given initial polarizations of incoming particles, the polarization of the outgoing electron beam is the same for Moller and Bhabha scattering and is energy independent. However, in various electroweak gauge models, we find that the energy dependence and final-state polarizations are in general different for the two scattering processes; thus, observing polarization effects in such scattering processes may be useful to test various gauge models at high energy.
10700275
One-loop effective brane action
The one-loop effective action for a p brane embedded in a D = p+2 Minkowski spacetime in the static gauge is calculated. Rescaling the quantum fluctuation by (−g0)1/2 evaluated on the background brane leads to the one-loop effective action expressed only in terms of infrared and ultraviolet divergent geometric scalars. After the infrared divergences are absorbed into the quantum fluctuation, there remains the finite number of ultraviolet divergences. This implies that the D = p+2 Poincare symmetry and the D = p+1 general coordinate invariance are preserved in one-loop order.