Bad parrhesia: the limits of cynicism in the public sphere

This paper examines the limits of Cynical parrhesia. Based on fieldwork with artist‐activists in post‐recession Dublin, I recount their fraught efforts to use adventurous artistic expression to provoke a critical awakening in an audience of strangers, who instead respond with derision. My focus is thus on a narrow but prevalent feature of artists’ work and lives, and the public’s experience of challenging genres of provocative public criticism: the encounter with unintelligibility and alienation in the public sphere. I thus deploy ‘bad parrhesia’ as a tool through which to consider the factors that mitigate against artists establishing the desired critical relationship with audiences. Nevertheless, though these parrhesiastic encounters do not succeed, I argue that they do not yield an absence of social relations but relations of an anti‐social kind. Departing from readings of parrhesia as a form of individualism, corrosive to relationality, or a playful reaction against the failures of liberal democratic politics, I make a case for framing parrhesia as a relationship of contestation over which kinds of public criticism are judged to be intelligible and valuable responses to moments of cultural crisis in northern liberal democracies

Glueball Matrix Elements on Anisotropic Lattices

The glueball-to-vacuum matrix elements of local gluonic operators in scalar, tensor, and pseudoscalar channels are investigated numerically on several anisotropic lattices with the spatial lattice spacing in the range 0.1fm -- 0.2fm. These matrix elements are needed to predict the glueball branching ratios in $J/\psi$ radiative decays which will help to identify the glueball states in experiments. Two types of improved local gluonic operators are constructed for a self-consistent check, and the finite volume effects are also studied. The lattice spacing dependence of our results is very small and the continuum limits are reliably extrapolated.Comment: 3 pages, 3 figures, Lattice2003 (spectrum

The glueball spectrum from an anisotropic lattice study

The spectrum of glueballs below 4 GeV in the SU(3) pure-gauge theory is investigated using Monte Carlo simulations of gluons on several anisotropic lattices with spatial grid separations ranging from 0.1 to 0.4 fm. Systematic errors from discretization and finite volume are studied, and the continuum spin quantum numbers are identified. Care is taken to distinguish single glueball states from two-glueball and torelon-pair states. Our determination of the spectrum significantly improves upon previous Wilson action calculations.Comment: 14 pages, 8 figures, uses REVTeX and epsf.sty (final version published in Physical Review D

Comment on the "Coupling Constant and Quark Loop Expansion for Corrections to the Valence Appeoximation" by Lee and Weingarten

Lee and Weingarten have recently criticized our calculation of quarkonium and glueball scalars as being "incomplete" and "incorrect". Here we explain the relation of our calculations to full QCD.Comment: 5 pages,2 epsfigs. Submitted to the Comment section of Phys. Rev. D 28th April 199

O(αsa)O(\alpha_{s}a) matching coefficients for axial vector current and ΔB\Delta B==2 operator

We present a calculation of the perturbative matching coefficients including mixing with higher dimensional operators for the temporal component of the heavy-light axial current, $A_{4}$, and the $\Delta B=2$ operator, $O_S$. For $A_{4}^{\scriptsize static, NRQCD}$, calculations with various RG-improved gauge actions are peformed. Matching coefficients with NRQCD and heavy-clover actions are also compared.Comment: LATTICE99 (Heavy Quarks), 3 pages, 2 figures, espcrc2.st

Current status of Dynamical Overlap project

We discuss the adaptation of the Hybrid Monte Carlo algorithm to overlap fermions. We derive a method which can be used to account for the delta function in the fermionic force caused by the differential of the sign function. We discuss the algoritmic difficulties that have been overcome, and mention those that still need to be solved.Comment: Talk given at Workshop on Computational Hadron Physics, Nicosia, September 2005. 8 page

The Lattice Schwinger Model: Confinement, Anomalies, Chiral Fermions and All That

In order to better understand what to expect from numerical CORE computations for two-dimensional massless QED (the Schwinger model) we wish to obtain some analytic control over the approach to the continuum limit for various choices of fermion derivative. To this end we study the Hamiltonian formulation of the lattice Schwinger model (i.e., the theory defined on the spatial lattice with continuous time) in $A_0=0$ gauge. We begin with a discussion of the solution of the Hamilton equations of motion in the continuum, we then parallel the derivation of the continuum solution within the lattice framework for a range of fermion derivatives. The equations of motion for the Fourier transform of the lattice charge density operator show explicitly why it is a regulated version of this operator which corresponds to the point-split operator of the continuum theory and the sense in which the regulated lattice operator can be treated as a Bose field. The same formulas explicitly exhibit operators whose matrix elements measure the lack of approach to the continuum physics. We show that both chirality violating Wilson-type and chirality preserving SLAC-type derivatives correctly reproduce the continuum theory and show that there is a clear connection between the strong and weak coupling limits of a theory based upon a generalized SLAC-type derivative.Comment: 27 pages, 3 figures, revte

Tadpole-improved SU(2) lattice gauge theory

A comprehensive analysis of tadpole-improved SU(2) lattice gauge theory is made. Simulations are done on isotropic and anisotropic lattices, with and without improvement. Two tadpole renormalization schemes are employed, one using average plaquettes, the other using mean links in Landau gauge. Simulations are done with spatial lattice spacings $a_s$ in the range of about 0.1--0.4 fm. Results are presented for the static quark potential, the renormalized lattice anisotropy $a_t/a_s$ (where $a_t$ is the ``temporal'' lattice spacing), and for the scalar and tensor glueball masses. Tadpole improvement significantly reduces discretization errors in the static quark potential and in the scalar glueball mass, and results in very little renormalization of the bare anisotropy that is input to the action. We also find that tadpole improvement using mean links in Landau gauge results in smaller discretization errors in the scalar glueball mass (as well as in the static quark potential), compared to when average plaquettes are used. The possibility is also raised that further improvement in the scalar glueball mass may result when the coefficients of the operators which correct for discretization errors in the action are computed beyond tree level.Comment: 14 pages, 7 figures (minor changes to overall scales in Fig.1; typos removed from Eqs. (3),(4),(15); some rewording of Introduction

Measuring the aspect ratio renormalization of anisotropic-lattice gluons

Using tadpole inproved actions we investigate the consistency between different methods of measuring the aspect ratio renormalization of anisotropic-lattice gluons for bare aspect ratios \chi_0=4,6,10 and inverse lattice spacing in the range a_s^{-1}=660-840 MeV. The tadpole corrections to the action, which are established self-consistently, are defined for two cases, mean link tadpoles in Landau gauge and gauge invariant mean plaquette tadpoles. Parameters in the latter case exhibited no dependence on the spatial lattice size, L, while in the former, parameters showed only a weak dependence on L easily extrapolated to L=\infty. The renormalized anisotropy \chi_R was measured using both the torelon dispersion relation and the sideways potential method. We found good agreement between these different approaches. Any discrepancy was at worst 3-4% which is consistent with the effect of lattice artifacts that for the torelon we estimate as O(\a_Sa_s^2/R^2) where R is the flux-tube radius. We also present some new data that suggests that rotational invariance is established more accurately for the mean-link action than the plaquette action.Comment: LaTeX 18 pages including 7 figure

The flavour singlet mesons in QCD

We study the flavour singlet mesons from first principles using lattice QCD. We explore the splitting between flavour singlet and non-singlet for vector and axial mesons as well as the more commonly studied cases of the scalar and pseudoscalar mesons.Comment: 12 pages, LATEX, 4 ps figure