Using QM-Sutton-Chen many-body potential, we have studied the 1/2a〈1 1 0〉 screw dislocation in nickel (Ni) via molecular dynamics (MD) simulations. We have studied core energy and structure using a quadrupolar dislocation system with 3D periodic boundary conditions. The relaxed structures show dissociation into two partials on {1 1 1} planes. The equilibrium separation distance between the two ...

From the basic chiral and anti-chiral Poisson bracket algebra of the SL(2, R) WZNW model, non-equal time Poisson brackets are derived. Through Hamiltonian reduction we deduce the corresponding brackets for its coset theories. The analysis of WZNWmodels is usually reduced to a separate treatment of its chiral or anti-chiral components [1, 2, 3]. But much simpler results can arise when the contri...

We compute the first radiative correction to the Casimir energy in the (d + 1)dimensional λ|φ|4 model submitted to quasi-periodic boundary conditions in one spatial direction. Our results agree with the ones found in the literature for periodic and antiperiodic boundary conditions, special cases of the quasi-periodic boundary conditions. The idea of introducing an arbitrary parameter in order t...

In recent years it has been observed that reaction]diffusion equations Ž . with Neumann boundary conditions as well as other classes of PDEs possess more symmetry than that which may be expected, and these ‘‘hidden’’ symmetries affect the generic types of bifurcation which occur Ž w x w x w x see Golubitsky et al. 6 , Field et al. 5 , Armbruster and Dangelmayr 1 , w x w x . Crawford et al. 2 , ...

Quantization of the Field This involves two main steps • make basic observables into operators, obeying canonical commutation relations (CCRs) • look for Hilbert space representations for these operators. Strategy: “put the field in a box” = pretend that the space is a torus = impose periodic boundary conditions of size L. The motivation for this is to get a discrete spectrum then to play with ...

In this paper, the effect of different boundary conditions on the free vibration analysis response of a sandwich plate is presented using the higher order shear deformation theory. The face sheets are orthotropic laminated composites that follow the first order shear deformation theory (FSDT) based on the Rissners-Mindlin (RM) kinematics field. The motion equations are derived considering the c...

We analyse boundary conformal field theories on random surfaces using the conformal gauge approach of David, Distler and Kawai. The crucial point is the choice of boundary conditions on the Liouville field. We discuss the Weyl anomaly cancellation for Polyakov’s non-critical open bosonic string with Neumann, Dirichlet and free boundary conditions. Dirichlet boundary conditions on the Liouville ...

In this paper, free vibration analysis of orthotropic functionally graded material (FGM) cylinders was carried out by a Mesh-Free method. In this analysis, moving least squares shape functions are used for approximation of displacement field in the weak form of equilibrium equation. Essential boundary conditions are imposed by transformation method. In this simulation, an axisymmetric model is ...

Casimir forces are conventionally computed by analyzing the effects of boundary conditions on a fluctuating quantum field. Although this analysis provides a clean and calculationally tractable idealization, it does not always accurately capture the characteristics of real materials, which cannot constrain the modes of the fluctuating field at all energies. We study the vacuum polarization energ...