q-Legendre Transformation: Partition Functions and Quantization of the Boltzmann Constant

In this paper we construct a q-analogue of the Legendre transformation, where q is a matrix of formal variables defining the phase space braidings between the coordinates and momenta (the extensive and intensive thermodynamic observables). Our approach is based on an analogy between the semiclassical wave functions in quantum mechanics and the quasithermodynamic partition functions in statistical physics. The basic idea is to go from the q-Hamilton-Jacobi equation in mechanics to the q-Legendre transformation in thermodynamics. It is shown, that this requires a non-commutative analogue of the Planck-Boltzmann constants (hbar and k_B) to be introduced back into the classical formulae. Being applied to statistical physics, this naturally leads to an idea to go further and to replace the Boltzmann constant with an infinite collection of generators of the so-called epoch\'e (bracketing) algebra. The latter is an infinite dimensional noncommutative algebra recently introduced in our previous work, which can be perceived as an infinite sequence of "deformations of deformations" of the Weyl algebra. The generators mentioned are naturally indexed by planar binary leaf-labelled trees in such a way, that the trees with a single leaf correspond to the observables of the limiting thermodynamic system

Over Vlees, Vis en het Rapport Brandt

In ESB van 27 mei komt dr. A. E. van Niekerk (,,Het Brandt-rapport is vices noch vis", biz. 516-518) o.m. terug op mijn bespreking in dit blad (5 maart 1980, biz. 263-270) van het rapport- Brandt. Naar zijn mening is er in Nederland niet voldoende kritisch over gedacht. Hij had graag ook in ons land meer kritiek gezien, waarschijnlijk om bepaalde regeringen van ontwikkelde landen een alibi te verschaffen voor him tekortschietende gedrag. Als we overigens in de politick moesten wachten tot de wetenschappers en andere deskundigen het eens zijn, zou er nooit iets gebeuren. Dit verlangen naar meer kritiek — in belangrijker landen dan Nederland al behoorlijk gespuid — lijkt mij contraproduktief

The Diamond, January 25, 2001

Front Page: Positive Airwaves Webcasting; Talent Extravaganza in the Works News: Three New Professors Join Dordt; St. Olaf Orchestra to Perform in B.J. Haan Auditorium; SAC Hosts Events; Club Day Brings New Opportunities; Dordt Offers Various Clubs; Concert Choir Tours Over Christmas Break Opinion: What Gets You Out of Bed?; Challenge Yourself Off-Campus; Respect Authority: Leave on Time Features: Mexico Changes Lives; Students Serve in Nicaragua A & E: Van Den Hul to Give Recital; ACTF Festival Enriches Dordt; Coldplay: Not Ear Candy; NISO to Feature Folk Music Sports: Senior Basketball Players Lead on and off the Court; Hockey Tour Strengthens Team World: News Briefs; Lookback; Political Integrity a Thing of the Pasthttps://digitalcollections.dordt.edu/dordt_diamond/1188/thumbnail.jp

High-pressure structural, elastic and electronic properties of the scintillator host material, KMgF_3

The high-pressure structural behaviour of the fluoroperovskite KMgF_3 is investigated by theory and experiment. Density functional calculations were performed within the local density approximation and the generalized gradient approximation for exchange and correlation effects, as implemented within the full-potential linear muffin-tin orbital method. In situ high-pressure powder x-ray diffraction experiments were performed up to a maximum pressure of 40 GPa using synchrotron radiation. We find that the cubic Pm\bar{3}m crystal symmetry persists throughout the pressure range studied. The calculated ground state properties -- the equilibrium lattice constant, bulk modulus and elastic constants -- are in good agreement with experimental results. By analyzing the ratio between the bulk and shear modulii, we conclude that KMgF_3 is brittle in nature. Under ambient conditions, KMgF_3 is found to be an indirect gap insulator with the gap increasing under pressure.Comment: 4 figure

On the Covariant Quantization of the 2nd-Ilk Superparticle

This paper is devoted to the quantization of the second-ilk superparticle using the Batalin-Vilkovisky method. We show the full structure of the master action. By imposing gauge conditions on the gauge fields rather than on coordinates we find a gauge-fixed quantum action which is free. The structure of the BRST charge is exhibited and the BRST cohomology yields the same physical spectrum as the light- cone quantization of the usual superparticle.Comment: 17 page

Covariant Quantization of the Brink-Schwarz Superparticle

The quantization of the Brink-Schwarz-Casalbuoni superparticle is performed in an explicitly covariant way using the antibracket formalism. Since an infinite number of ghost fields are required, within a suitable off-shell twistor-like formalism, we are able to fix the gauge of each ghost sector without modifying the physical content of the theory. The computation reveals that the antibracket cohomology contains only the physical degrees of freedom.Comment: 24 page

Conquest of the ghost pyramid of the superstring

We give a new Becchi-Rouet-Stora-Tyutin operator for the superstring. It implies a quadratic gauge-fixed action, and a new gauge-invariant action with first-class constraints. The infinite pyramid of spinor ghosts appears in a simple way through ghost gamma matrices.Comment: 30 pages, 1 figure, Late

An Introduction to the Covariant Quantization of Superstrings

We give an introduction to a new approach to the covariant quantization of superstrings. After a brief review of the classical Green--Schwarz superstring and Berkovits' approach to its quantization based on pure spinors, we discuss our covariant formulation without pure spinor constraints. We discuss the relation between the concept of grading, which we introduced to define vertex operators, and homological perturbation theory, and we compare our work with recent work by others. In the appendices, we include some background material for the Green-Schwarz and Berkovits formulations, in order that this presentation be self contained.Comment: LaTex, 23 pp. Contribution to the Proceedings of the Workshop in String Theory, Leuven 2002, some references added and a comment on ref. [16

The Quantum Superstring as a WZNW Model with N=2 Superconformal Symmetry

We present a new development in our approach to the covariant quantization of superstrings in 10 dimensions which is based on a gauged WZNW model. To incorporate worldsheet diffeomorphisms we need the quartet of ghosts (b_{zz},c^{z}, \b_{zz}, \g^{z}) for topological gravity. The currents of this combined system form an N=2 superconformal algebra. The model has vanishing central charge and contains two anticommuting BRST charges, Q_{S}=Q_{W} + \oint \g^{z} b_{zz} + \oint \eta_{z} and Q_{V} = \oint c^{z} \Big(T^{W}_{zz} + {1\over 2} T^{top}_{zz}\Big) + \g^{z} (B^{W}_{zz} + {1\over 2} B^{top}_{zz} \Big), where $\eta_{z}$ is obtained by the usual fermionization of \b_{zz}, \g^{z}. Physical states form the cohomology of $Q_{S}+Q_{V}$, have nonnegative grading, and are annihilated by $b_{0}$ and $\beta_{0}$. We no longer introduce any ghosts by hand, and the formalism is completely Lorentz covariant.Comment: 26 pages, harmvac; major additions and new result