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F. Gliozzi

Publications and source records attributed to F. Gliozzi.

54 records · Page 3Linked to original sources
arXiv1994

ADE functional dilogarithm identities and integrable models

We describe a new infinite family of multi-parameter functional equations for the Rogers dilogarithm, generalizing Abel's and Euler's formulas. They are suggested by the Thermodynamic Bethe Ansatz approach to the Renormalization Group flow of 2D integrable, ADE-related quantum field theories. The known sum rules for the central charge of critical fixed points can be obtained as special cases of these. We conjecture that similar functional identities can be constructed for any rational integrable quantum field theory with factorized S-matrix and support it with extensive numerical checks.

hep-th↗
arXiv1994

The Width of the Colour Flux Tube

We discuss and rederive in a general way the logarithmic growth of the mean squared width of the colour flux tube as a function of the interquark separation. Recent data on 3D $Z_2$ gauge theory, combined with high precision data on the interface physics of the 3D Ising model fit nicely this behaviour over a range of more than two orders of magnitude.

hep-lat↗
arXiv1994

Rough Interfaces Beyond the Gaussian Approximation

We compare predictions of the Capillary Wave Model with Monte Carlo results for the energy gap and the interface energy of the 3D Ising model in the scaling region. Our study reveals that the finite size effects of these quantities are well described by the Capillary Wave Model, expanded to two-loop order (one order beyond the Gaussian approximation).

hep-lat↗
arXiv1994

Quantum Behaviour of the Flux Tube: A comparison between QFT predictions and lattice gauge theory simulations

We review some universal features of the colour flux tube of gauge theories in the confining phase predicted by the infrared conformal limit of the underlying string theory. In particular we discuss shape effects in Wilson loops and rederive in a general way the logarithmic growth of the mean square width of the flux tube as a function of the interquark separation. Recent data on three-dimensional Z_2 gauge theory, combined with high precision data on the interface physics of the 3D Ising model fit nicely to this behaviour over a range of more than two orders of magnitude

hep-lat↗
arXiv1994

Fluid Interfaces in the 3D Ising Model as a Dilute Gas of Handles

We study the topology of fluid interfaces in the 3D Ising model in the rough phase. It turns out that such interfaces are accurately described as dilute gases of microscopic handles, and the stiffness of the interface increases with the genus. The number of configurations of genus $g$ follows a Poisson-like distribution. The probability per unit area for creating a handle is well fitted in a wide range of the inverse temperature $β$ near the roughening point by an exponentially decreasing function of $β$. The procedure of summing over all topologies results in an effective interface whose squared width scales logarithmically with the lattice size.

cond-mat↗
arXiv1994

Rough Interfaces Beyond the Gaussian Approximation

We compare predictions of the Capillary Wave Model beyond its Gaussian approximation with Monte Carlo results for the energy gap and the surface energy of the 3D Ising model in the scaling region. Our study reveals that the finite size effects of these quantities are well described by the Capillary Wave Model, expanded to two--loop order ( one order beyond the Gaussian approximation).

hep-lat↗
arXiv1994

On the relation between the width of the flux tube and $T_c^{-1}$ in lattice gauge theories

Within the framework of a quantum flux tube model for the interquark potential it is possible to predict that in (2+1) dimensions the space-like string tension must increase with the temperature in the deconfined phase and that the thickness of the flux tube must coincide with the inverse of the deconfinement temperature. Both these predictions are in good agreement with some recent numerical simulations of SU(2) and $Z_2$ gauge models.

hep-lat↗
arXiv1994

Finite Size Effects in Fluid Interfaces

It is shown that finite size effects in the free energy of a rough interface of the 3D Ising and three--state Potts models are well described by the capillary wave model at {\em two--loop} order. The agreement between theoretical predictions and Monte Carlo simulations strongly supports the idea of the universality of this description of order--order interfaces in 3D statistical systems above the roughening temperature.

hep-lat↗
arXiv1994

Self-avoiding random surfaces with fluctuating topology

A gas of self-avoiding surfaces with an arbitrary polynomial coupling to the gaussian curvature and an extrinsic curvature term can be realized in a three-dimensional Ising bcc lattice with only three local couplings. Similar three parameter realizations are valid also in other lattices. The relation between the crumpling transition and the roughening is discussed. It turns out that the mean area of these surfaces is proportional to its genus.

hep-lat↗
arXiv1993

On the behaviour of spatial Wilson loops in the high temperature phase of Lattice Gauge Theories

The behaviour of the space-like string tension in the high temperature phase is studied. Data obtained in the $Z_2$ gauge model in (2+1) dimensions are compared with predictions of a simple model of a fluctuating flux tube with finite thickness. It is shown that in the high temperature phase contributions coming from the fluctuations of the flux tube vanish. As a consequence we also show that in (2+1) dimensional gauge theories the thickness of the flux tube coincides with the inverse of the deconfinement temperature.

hep-lat↗
arXiv1993

Condensation of handles in the interface of 3D Ising model

We analyze the microscopic, topological structure of the interface between domains of opposite magnetization in 3D Ising model near the critical point. This interface exhibits a fractal behaviour with a high density of handles. The mean area is an almost linear function of the genus. The entropy exponent is affected by strong finite-size effects.

hep-th↗
arXiv1992

Finite-Size Effects in the Interface of 3D Ising Model

The interface between domains of opposite magnetization in the 3D Ising model near the critical temperature displays universal finite-size effects which can be described in terms of a gaussian model of capillary waves. It turns out that these finite-size corrections depend rather strongly on the shape of the lattice. This prediction, which has no adjustable parameters, is tested and accurately verified for various lattice shapes by means of numerical simulations with a cluster algorithm. This supports also a long-standing conjecture on the finite-size effects in Wilson loops of Lattice Gauge Theories.

hep-lat↗
arXiv1992

Some universal features of the effective string picture of pure gauge theories

The effective string describing the large distance behaviour of the quark sources of gauge field theories in the confining phase in D=3 or D=4 space-time dimensions can be formulated, in the infrared limit, as a suitable 2D conformal field theory on surfaces with quark loops as boundaries. Recent results on self-avoiding random surfaces allow to fix almost uniquely such a conformal theory. As a consequence, some universal relationships among the string tension , the thickness of the colour flux tube, the deconfinement temperature and a lower bound of the glueball mass spectrum are found. The general agreement with the data extracted from recent lattice simulations with different gauge groups is rather impressive.(Talk held by F.Gliozzi at Lattice'92 , Amsterdam)

hep-lat↗
arXiv1992

The infrared limit of QCD effective string

Some model-independent properties of the effective string of gauge field systems in the confining phase , for very large quark separations, are described in terms of two-dimensional conformal field theories. The constraints induced by the gauge theory at the boundaries of the effective string induce a Coulomb- like term in the interquark potential which is universal, but different from the one proposed by Lüscher. Some universal relations among the string tension, the thickness of the colour flux tube, the location of the deconfining temperature and a lower bound of the glueball spectrum are discussed. (Lectures given at the XXXII Cracow School of Theoretical Physics, Zakopane, Poland 2-12 June 1992)

hep-lat↗
arXiv1992

The Effective String of 3D Z_2 Gauge Theory as a c=1 compactified CFT

We report on a high precision Montecarlo test of the three dimensional Ising gauge model at finite temperature. The string tension $σ$ is extracted from the expectation values of correlations of Polyakov lines. Agreement with the string tension extracted from Wilson loops is found only if the quantum fluctuations of the flux tube are properly taken into account. The central charge of the underlying conformal field theory is c=1.

hep-lat↗
arXiv1991

Self-avoiding effective strings in lattice gauge theories

It is shown that the effective string recently introduced to describe the long distance dynamics of 3D gauge systems in the confining phase has an intriguing description in terms of models of 2D self-avoiding walks in the dense phase. The deconfinement point, where the effective string becomes N=2 supersymmetric, may then be interpreted as the tricritical Theta point where the polymer chain undergoes a collapse transition. As a consequence, a universal value of the deconfinement temperature is predicted.

hep-th↗
arXiv1991

Critical Boundary Conditions for the Effective String

Gauge systems in the confining phase induce constraints at the boundaries of the effective string, which rule out the ordinary bosonic string even with short distance modifications. Allowing topological excitations, corresponding to winding around the colour flux tube, produces at the quantum level a universal free fermion string with a boundary phase nu=1/4. This coincides with a model proposed some time ago in order to fit Monte Carlo data of 3D and 4D Lattice gauge systems better. A universal value of the thickness of the colour flux tube is predicted.

hep-th↗