15 research outputs found
Noncentral extensions as anomalies in classical dynamical systems
A two cocycle is associated to any action of a Lie group on a symplectic
manifold. This allows to enlarge the concept of anomaly in classical dynamical
systems considered by F. Toppan [in J. Nonlinear Math. Phys. 8, no.3 (2001)
518-533] so as to encompass some extensions of Lie algebras related to
noncanonical actions.Comment: arxiv version is already officia
Light Hadron Spectroscopy and Decay at BESIII
Light hadron spectroscopy plays an important role in understanding the decay
dynamics of unconventional hadronic states, such as strangeonium and glueballs.
BESIII provides an ideal avenue to search for these exotic states thanks to a
huge amount of data recorded at various energy points in the tau-charm mass
region including J/psi resonance. This report summarizes recent results of the
BESIII experiment related to the glueballs and strangeonium-like states.Comment: 6 pages, 5 figures, Conference proceeding of FPCP-201
Trapped interacting two-component bosons
In this paper we solve one dimensional trapped SU(2) bosons with repulsive
-function interaction by means of Bethe-ansatz method. The features of
ground state and low-lying excited states are studied by numerical and analytic
methods. We show that the ground state is an isospin "ferromagnetic" state
which differs from spin-1/2 fermions system. There exist three quasi-particles
in the excitation spectra, and both holon-antiholon and holon-isospinon
excitations are gapless for large systems. The thermodynamics equilibrium of
the system at finite temperature is studied by thermodynamic Bethe ansatz. The
thermodynamic quantities, such as specific heat etc. are obtained for the case
of strong coupling limit.Comment: 15 pages, 9 figure
Generalized q-Oscillators and their Hopf Structures
We study the relationships among the various forms of the oscillator
algebra and consider the conditions under which it supports a Hopf structure.
We also present a generalization of this algebra together with its
corresponding Hopf structure. Its multimode extensions are also considered.Comment: 14 page
Realizations of the -Heisenberg and -Virasoro Algebras
We give field theoretic realizations of both the -Heisenberg and the
-Virasoro algebra. In particular, we obtain the operator product expansions
among the current and the energy momentum tensor obtained using the Sugawara
construction.Comment: 9 page
Initial Conditions for Semiclassical Field Theory
Semiclassical approximation based on extracting a c-number classical
component from quantum field is widely used in the quantum field theory.
Semiclassical states are considered then as Gaussian wave packets in the
functional Schrodinger representation and as Gaussian vectors in the Fock
representation. We consider the problem of divergences and renormalization in
the semiclassical field theory in the Hamiltonian formulation. Although
divergences in quantum field theory are usually associated with loop Feynman
graphs, divergences in the Hamiltonian approach may arise even at the tree
level. For example, formally calculated probability of pair creation in the
leading order of the semiclassical expansion may be divergent. This observation
was interpretted as an argumentation for considering non-unitary evolution
transformations, as well as non-equivalent representations of canonical
commutation relations at different time moments. However, we show that this
difficulty can be overcomed without the assumption about non-unitary evolution.
We consider first the Schrodinger equation for the regularized field theory
with ultraviolet and infrared cutoffs. We study the problem of making a limit
to the local theory. To consider such a limit, one should impose not only the
requirement on the counterterms entering to the quantum Hamiltonian but also
the requirement on the initial state in the theory with cutoffs. We find such a
requirement in the leading order of the semiclassical expansion and show that
it is invariant under time evolution. This requirement is also presented as a
condition on the quadratic form entering to the Gaussian state.Comment: 20 pages, Plain TeX, one postscript figur
One dimensional SU(3) bosons with function interaction
In this paper we solve one dimensional SU(3) bosons with repulsive
-function interaction by means of Bethe ansatz method. The features of
ground state and low-lying excited states are studied by both numerical and
analytic methods. We show that the ground state is a SU(3) color ferromagnetic
state. The configurations of quantum numbers for the ground state are given
explicitly. For finite system the spectra of low-lying excitations and the
dispersion relations of four possible elementary particles (holon, antiholon,
-coloron and -coloron) are obtained by solving Bethe-ansatz
equation numerically. The thermodynamic equilibrium of the system at finite
temperature is studied by using the strategy of thermodynamic Bethe ansatz, a
revised Gaudin-Takahashi equation which is useful for numerical method are
given . The thermodynamic quantities, such as specific heat, are obtain for
some special cases. We find that the magnetic property of the model in high
temperature regime is dominated by Curie's law: and the
system has Fermi-liquid like specific heat in the strong coupling limit at low
temperature.Comment: RevTex 28 pages, 10 figure