相关论文: Exact effective action for fermions in one dimensi…
Some free--field spectral problems on a generalised cylinder are revisited. In two dimensions, conformal scalar effective actions for various boundary conditions are written in elliptic function terms and some special values given. Fermions…
We consider two-component fermions with short-range interactions and large scattering length. This system has universal properties that are realized in several different fields of physics. In the limit of large fermion-fermion scattering…
This is a more detailed version of our recent paper where we proposed, from first principles, a direct method for evaluating the exact fermion propagator in the presence of a general background field at finite temperature. This can, in…
The scattering of Dirac fermions on the sine-Gordon kink is studied both analytically and numerically. To achieve invariance with respect to a discrete symmetry, the sine-Gordon model is treated as a nonlinear $\sigma$-model with a circular…
We present, from first principles, a direct method for evaluating the exact fermion propagator in the presence of a general background field at finite temperature, which can be used to determine the finite temperature effective action for…
We consider interactions of fermions with the domain wall bubbles produced during a first order phase transition. A new exact solution of the Dirac equations is obtained for a wall profile incorporating a position dependent phase factor.…
We investigate the interaction of fermions having both Dirac and left-handed and right-handed Majorana mass terms with vacuum domain walls. By solving the equations of motion in thin-wall approximation, we calculate the reflection and…
We evaluate the parity-odd part of the effective action due to massive Dirac fermions on a $S^2 \times S^1$ manifold, minimally coupled to an external Abelian gauge field. We do that for a special class of gauge-field configurations, which…
We consider the scattering of fermions off antifermions with spin 1/2 and 3/2. Starting from helicity partial-wave scattering amplitudes we derive transformations that eliminate all kinematical constraints. Such amplitudes are expected to…
We discuss locality in the domain-wall QCD through the effective four-dimensional Dirac operator which is defined by the transfer matrix of the five-dimensional Wilson fermion. We first derive an integral representation for the effective…
Some new expressions are found, concerning the one-loop effective action of four dimensional massive and massless Dirac fermions in the presence of general uniform electric and magnetic fields, with $\vec E\cdot \vec H\neq 0$ and $\vec E…
The complete nonperturbative expressions for the high-temperature expansion of the one-loop effective action induced by the charged scalar and the charged Dirac particles both at zero and finite temperatures are derived with account for…
Recently, properties of the fixed point action for fermion theories have been pointed out indicating realization of chiral symmetry on the lattice. We check these properties by numerical analysis of the spectrum of a parametrized fixed…
We derived the corresponding boundary condition on Fermi fields to the spin-1/2 Heisenberg chain with boundary magnetic fields. In order to obtain the correct boundary condition from the variation of the action at the edges, we carefully…
We investigate the problem of backscattering off a time-dependent and spatially extended barrier in a one-dimensional electron gas. By performing a perturbative expansion in the backscattering amplitude, we compute the total energy density…
We consider interactions of fermions with the domain wall bubbles produced during the first order phase transitions. New exact solution of Dirac equations and reflection coefficient are obtained.
We calculate the Casimir interaction between two short range scatterers embedded in a background of one dimensional massless Dirac fermions using a force operator approach. We obtain the force between two finite width square barriers, and…
In this paper, we present an improvement of a method for computing scattering amplitudes that include external (polarized) fermions with the following features: the formulas are quite general and work for different kinematic configurations…
We describe the influence of the gapless, nodal, fermionic quasiparticles of a two-dimensional d-wave superconductor on the motion of vortices. A continuum, functional formalism is used to obtain the effective vortex action, after the…
We study quantum effects due to a Dirac field in 2+1 dimensions, confined to a spatial region with a non-trivial boundary, and minimally coupled to an Abelian gauge field. To that end, we apply a path-integral representation, which is…