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 ...

A more efficient water use system is needed for agriculture. This is more evidence for rice production with a higher water use for economical production. A large cultivar×water regime interaction exists for grain yield in rice. Therefore, information is required to adopt new rice cultivars with high yield potential under water-saving conditions. The objectives of this study were to analyze the ...

Pistachio is the most important nut that is produced in Iran. Little research has been done to examine the effect of UCB1-hybride rootstock plants as tissue culture for pistachios (2011 in Toba company).This study aims to evaluate three pistachio varieties on UCB1 hybrid rootstock.  The experiment was conducted as a randomized complete block design with three treatment groups (including Ohadi, ...

Frost damage to the flowers and early developing fruits is one of the most limiting factors in the most almond cultivation regions of the world. This study was undertaken to help understand almond response to frost spring at same phenological stage, in order to develop criteria for the selection of cultivars with improved resistance to frost on the basis of field and laboratory experiments. In ...