STATISTICAL MECHANICS AND FIELD THEORY
        ======================================

   Statistical Mechanics is a traditional subject in Florence, which
has been accounted for by this 16-year old INFN initiative. 
Teams of other cities have joined and left during the years. 
Most of the people had a field theory background, and thus have been
investigating the fruitful relations and analogies among statistical
mechanics, condensed matter and particle physics.

  This INFN Specific Initiative was re-organized last year (i.e. in 1998): 
old teams from outside Florence left and two new groups of Genova 
and Trieste joined. There is a renewed emphasis on the applications of 
field theory to statistical mechanics and condensed matter problems.
In particular, the exactly solvable models in two dimensions, namely
the conformal field theories and the integrable systems, provide
the tools to understand many new physical problems which are characterized
by strong interactions and non-perturbative effects. 

  There is a rather broad spectrum of strongly-interacting systems in
statistical mechanics, and, similarly, there are many subjects 
analyzed by the participants of this INFN Initiative.
Among many others, let us mention the quantum Hall effect and in general
the strongly-interacting electron systems in low dimension,
the random and disordered systems, the spin glasses, the open systems 
out of equilibrium, the many-body dynamical systems and the approach 
to equilibrium near a phase transition.
 
 We would like to remark that these are rather specific phenomena, but 
their solution might influence theoretical and mathematical physics at large 
(for example, this has occurred in the case of solitons). 
Furthermore, we remark that exact methods test the fundamental aspects 
of field theory and allow us to address basic issues like the 
irreversibility of the renormalization-group flow (i.e. the c-theorem).

INVITATIONS OF FOREIGN RESEARCHERS
==================================

 - S. Ruffo asks 1M for inviting P. Holdsworth (ENS-Lyon) for 1 week;
 - S. Marmi asks 1M for inviting  Sauzin e Yoccoz for 1 week;
 - A. Cappelli asks 2M for inviting G.R.Zemba for 1 month.

Special request

Giuseppe Mussardo ask support for partecipating on may 2000 
(for a month) to the extended workshop on "Quantum Field 
Theory and Statistical Mechanics" to be held in Montreal.

 FIRENZE FI11/2000 PROGRAM
 =========================

 - A.Cappelli and F. Colomo
 ``Study of statistical models with frustration and no quenched disorder''
 Try to solve the frustrated XY model; possible applications
 of the q-deformed algebras to solve exactly statistical models with
 disorder

 - A. Cappelli and G.R. Zemba; 
   A. Cappelli, L. Georgiev and I. Todorov
 ``Conformal field theories with W-infinity symmetry and the quantum Hall effect''
 Explore the physics of the W-infinity minimal models and try to propose an 
 experiment.
 Study the conformal field theories for the non-Abelian Hall states.

 - S. Ruffo, T. Cretegny, T. Dauxois and A. Torcini
 ``Dynamics of breathers in spin chains''
 Exact and numerical study of breather solutions and their stability.

 - S. Ruffo, V. Latora and A. Rapisarda;
   S. Ruffo, X. Leoncini, A.D. Verga, P. Holdsworth,
 ``Dynamics near the phase transition''
 Applications to plasma physics and fragmentation of nuclei.

 - S. Ruffo, F. Izrailev and L. Tessieri
 ``Anderson localization''
 An original analytic method will be further applied to certain random 
 matrix models

 - F. Bagnoli, M. Bezzi, P. Palmerini and R. Rechtman
 ``Cellular Automata and Self-organized Criticality''
 Sincronization of extended chaotic systems. Cellular automata and algorithms
 for parallel computing.

 - S. Marmi, P. Moussa and J.-C. Yoccoz,
 ``Renormalization and the problem of small divisors''
 The (complex) renormalization group applied to some Hamiltonian systems

 - S. Marmi and D. Sauzin,
 ``Asymptotic analysis and Borel summability in the Hamilton-Jacobi equation''
 Study of the breaking of the separatrics in the perturbed pendulum and other 
 systems.

 - S. Marmi and J. Laskar
 ``Applications of the Laskar method of frequency analysis''
 Study other applications of this method, which has been used for celestial 
 mechanics and particle dynamics in high-energy accelerators.

 - M. Pettini, R. Franzosi, L. Casetti, C. Clementi, M. Modugno, G. Pettini 
   and R. Gatto
 ``Phase transitions and the topology changes in configuration space''
 The equipotential sub-manifolds of the configuration space of an Hamiltonian 
 system undergo a topology change in correspondence of a phase transition. 
 Further studies of this fact, which will apply the Morse theory.




 PREPRINTS
 ==========
- A. Cappelli, L. S. Georgiev, I. T. Todorov, 
  "A Unified Conformal Field Theory Description of Paired Quantum Hall States",
  preprint hep-th/9810105, 42 pages, Commun. Math. Phys. in press;

- V. Latora, A. Rapisarda, S. Ruffo,
  "Chaos and statistical mechanics in the Hamiltonian mean field model", 
  Physica D, in press, cond-mat/9803019;

- V. Latora, A. Rapisarda, S. Ruffo,
  "Superdiffusion and out-of-equilibrium chaotic dynamics with many degrees 
  of freedom",
  cond-mat/9904389, submitted to Phys. Rev. Lett. (1999).

- J. de Luca, A.J. Lichtenberg, S. Ruffo,
  "Finite times to equipartition in the thermodynamic limit", 
  preprint (1999),submitted to Phys. Rev. E.

- R. Franzosi, L. Casetti, L. Spinelli, M. Pettini, 
  "Topological aspects of geometrical signatures of phase transitions",
   cond-mat/9810180, submetted to Phys. Rev. E Rap. Comm.



 PROCEEDINGS
 ===========
- S. Ruffo,
  "The Fermi-Pasta-Ulam-Tsingou numerical experiment: time-scales for 
  the relaxation to thermodynamical equilibrium",
  in "Symmetry and perturbation theory", D. Bambusi and G. Gaeta eds., 
  Quaderni GNFM (Firenze,1998).

- S. Marmi,
  ``Chaotic behaviour in the solar system''
  Seminaire Bourbaki, Asterisque, in press

- S. Marmi,
  ``An introduction to small divisor problems'',
  preprint (Universita' di Pisa, Ph.D. School Lecture Notes)

- F. Bagnoli, F. Bochicchio, S. Bucci, 
  "Sensitivity of a LR-115 based radon dosemeter",
  proc of XIX Int. Conf. on Nuclear tracks, Radiation measurements
  (1999) in press.

- 

GENOVA FI11/2000 PROGRAM
========================

- N. Magnoli, R. Guida and G. Watts
- N. Magnoli, M. Caselle and P. Grinza
``Study of statistical models near criticality by using field theory''
Will study the equation of state of the Ising model in two dimensions.
Also compare analytic and numerical correlation functions in a magnetic field.

- N. Magnoli, K. Konishi, N. Maggiore and B. Carlino
``RG flow in the supersymmetric gauge theories''
Try to find the exact beta function from the low-energy solution by Seiberg 
and Witten.


- N. Magnoli, A. Cappelli and R. Guida
``Renormalization of the stress tensor in more than two-dimensions and
the extension of the c-theorem''
Study of the stress tensor three- and four-point functions and understand
the physical meaning of the various terms of the trace anomaly in higher
dimensions; critical analysis of the conjectured c-theorems in the recent
literature.

ADDITIONAL RESEARCHER
=====================
Starting from October 1999, Davide Fioravanti will join our group as
INFN post-doctoral fellow.


TRIESTE FI11/2000 PROGRAM
=========================
- G. Mussardo and collaborators.
 ``Supersymmetry in Statistical Models''
 Exact calculation of the matrix elements and correlators of order
 parameters in statistical models which present supersymmetry in
 their continuum limit.

 ``Non-integrable Quantum Field Theory''
 Development of new approches to study the spectrum and the dynamics of
 statistical models in a generic point of their phase diagram.

 ``Random System''
 Study Field Theory approaches to random systems.

 ``Boundary Field Theory''
 Study of the physical effects in field theories and strongly correlated
 systems induced by the boundary conditions imposed on the order parameters.

 ``Quantum Field Theory at Finite Temperature''
 Study of finite temperature effects in quantum field theories

 ``Renormalization Group''
 Calculation of universal ratios of Renormalization Group and
 study of the Renormalization Group Flows



PREPRINTS
=========

- G. Mussardo, S. Penati,
  QUANTUM FIELD THEORY WITH INFINITE RESONANCE STATES
  HEP-TH 9907039, submitted to Nucl. Phys. B

- G. Mussardo, P. Simon, 
  BOSONIC TYPE S MATRIX, VACUUM INSTABILITY AND CDD AMBIGUITIES,
  HEP-TH 9903072, submitted to Nucl. Phys. B.



PROCEEDINGS
===========

- G. Mussardo, 
  FORM-FACTORS IN OFF CRITICAL SUPERCONFORMAL MODELS, 
  Proc. Euroconf. on New Symmetries in Statistical Mechanics and Condensed 
  Matter Physics, Torino, Villa Gualino, Italy, 20 Jul - 1 Aug 1998.