We reexamine a unitary-transformation method of extracting a physical Hamiltonian from a gauge eld theory after quantizing all degrees of freedom including redundant variables. We show that this quantum Hamiltonian reduction method su ers from crucial modi cations arising from regularization of composite operators. We assess the e ects of regularization in the simplest gauge eld theory, the Sch...

A LiePoisson bracket is presented for a four-field gyrofluid model with compressible ions and magnetic field curvature, thereby showing the model to be Hamiltonian. In particular, in addition to commonly adopted magnetic curvature terms present in the continuity equations, analogous terms must be retained also in the momentum equations, in order to have a Lie-Poisson structure. The correspondin...

The spin-3/2 Ising model described by the most general Hamiltonian with an up-down symmetry

Article history: Received 29 December 2007 Received in revised form 5 May 2008 Accepted 26 October 2008

In this paper we study Multiple periodic solutions for a class of non-autonomous and convex Hamiltonian systems and we investigate use some properties of Ekeland index.  

The quantum dynamics of a driven single-band tight-binding model is considered. The relation between this Hamiltonian and Hamiltonian of the discrete-charge mesoscopic quantum circuits is investigated. It is shown that the former Hamiltonian, with closed boundary conditions, can be considered as a realization of the generalized para-fermionic polynomial algebras.