Temperature, chemical potential and the rho meson

We describe some applications of the Dyson-Schwinger equations at nonzero-(T,mu). Employing a simple model dressed-gluon propagator we determine the boundary of the deconfinement phase transition and the medium dependence of rho-meson properties. We introduce an extension to describe the time-evolution of scalar and vector self energies.Comment: 6 pages, LaTeX with 3 EPS figures; Contribution to the 'International Workshop XXVIII on Gross Properties of Nuclei and Nuclear Excitations', Hirschegg, Austria, 16-22.01.200

Alternative Archaeological Representations within Virtual Worlds

Traditional VR methods allow the user to tour and view the virtual world from different perspectives. Increasingly, more interactive and adaptive worlds are being generated, potentially allowing the user to interact with and affect objects in the virtual world. We describe and compare four models of operation that allow the publisher to generate views, with the client manipulating and affecting specific objects in the world. We demonstrate these approaches through a problem in archaeological visualization

An Algebraic Duality Theory for Multiplicative Unitaries

Multiplicative Unitaries are described in terms of a pair of commuting shifts of relative depth two. They can be generated from ambidextrous Hilbert spaces in a tensor C*-category. The algebraic analogue of the Takesaki-Tatsuuma Duality Theorem characterizes abstractly C*-algebras acted on by unital endomorphisms that are intrinsically related to the regular representation of a multiplicative unitary. The relevant C*-algebras turn out to be simple and indeed separable if the corresponding multiplicative unitaries act on a separable Hilbert space. A categorical analogue provides internal characterizations of minimal representation categories of a multiplicative unitary. Endomorphisms of the Cuntz algebra related algebraically to the grading are discussed as is the notion of braided symmetry in a tensor C*-category.Comment: one reference adde

Thermodynamic properties of a simple, confining model

We study the equilibrium thermodynamics of a simple, confining, DSE-model of 2-flavour QCD at finite temperature and chemical potential. The model has two phases: one characterised by confinement and dynamical chiral symmetry breaking; and the other by their absence. The phase boundary is defined by the zero of the vacuum-pressure difference between the confined and deconfined phases. Chiral symmetry restoration and deconfinement are coincident with the transition being of first order, except for $\mu=0$, where it is second order. Nonperturbative modifications of the dressed-quark propagator persist into the deconfined domain and lead to a dispersion law modified by a dynamically-generated, momentum-dependent mass-scale. This entails that the Stefan-Boltzmann limit for the bulk thermodynamic quantities is attained only for large values of temperature and chemical potential.Comment: 11 pages, LaTeX, epsfig.sty, elsart.st

Covariance, Dynamics and Symmetries, and Hadron Form Factors

We summarise applications of Dyson-Schwinger equations to the theory and phenomenology of hadrons. Some exact results for pseudoscalar mesons are highlighted with details relating to the U_A(1) problem. We describe inferences from the gap equation relating to the radius of convergence for expansions of observables in the current-quark mass. We recapitulate upon studies of nucleon electromagnetic form factors, providing a comparison of the ln-weighted ratios of Pauli and Dirac form factors for the neutron and proton.Comment: 9 pages, 2 figures. Contribution to proceedings of Workshop on Exclusive Reactions at High Momentum Transfer, May 21-24, 2007, Jefferson Lab, Newport News, V

Wavelet-based voice morphing

This paper presents a new multi-scale voice morphing algorithm. This algorithm enables a user to transform one person's speech pattern into another person's pattern with distinct characteristics, giving it a new identity, while preserving the original content. The voice morphing algorithm performs the morphing at different subbands by using the theory of wavelets and models the spectral conversion using the theory of Radial Basis Function Neural Networks. The results obtained on the TIMIT speech database demonstrate effective transformation of the speaker identity

Voice morphing using the generative topographic mapping

In this paper we address the problem of Voice Morphing. We attempt to transform the spectral characteristics of a source speaker's speech signal so that the listener would believe that the speech was uttered by a target speaker. The voice morphing system transforms the spectral envelope as represented by a Linear Prediction model. The transformation is achieved by codebook mapping using the Generative Topographic Mapping, a non-linear, latent variable, parametrically constrained, Gaussian Mixture Model