1. PHACT : Helicity amplitudes for present and future colliders - Alessandro Ballestrero,Dip Fisica Teorica
Helicity amplitudes calculations with the program PHACT are explained. Some examples of their application in WPHACT and SIXPHACT MC's are given. 1 Introduction The possibility of exploring higher and higher energies at present and future accelerators, entails the necessity of predicting and computing with high precision more and more complicated processes, with more external particles and more Feynman diagrams to be evaluated. This has lead to progressively abandon the old trace methods for perturbative computations and to use instead the helicity amplitudes ones. [1] In general these can be divided in three categories, depending on how the various fermionic lines appearing in a diagram are computed: by Trace evaluation,...

2. Cosmological Solution for the Problem of Rotation Velocities in Galaxies - Jose Luis,Fisica Teorica,U. A. M. Cantoblanco Madrid
this paper we have produced a confirmation of this suggestion (notice

3. Centre de Physique Th'eorique, Ecole Polytechnique F - 91128 Palaiseau (France) and Departamento de Fisica Teorica II, Universidad Complutense E - 28040 Madrid (Spain)
this paper will be devoted to discuss applications of the splitting lemma, and to show how it permits to unify a number of known (and, again, useful) results in equivariant dynamics and in particular in equivariant bifurcation theory.

4. Dipartimento di Fisica Teorica, Universit`a di Torino, V. P. Giuria 1, 10125 Torino, Italy A theoretical interpretation of the experimentally observed - M. Nardi
this paper we present our interpretation of these data, with a model of deconfinement transition based on percolation theory.

5. Symmetry and holonomy in M Theory - Varela Rizo, Oscar
SUMMARY Eleven-dimensional M Theory is conjectured to contain and unify quantum gravity and the rest of fundamental interactions. Despite its current lack of a precise formulation, hints and information about M Theory can be retrieved from its low energy limit, eleven-dimensional supergravity. In fact, this Thesis aims to make progress towards the understanding of M Theory by the study of eleven dimensional supergravity. Two important questions in M Theory yet to be solved are 1) how many supersymmetries can an M Theory background preserve and 2) what is the symmetry of M Theory. Both questions are addressed in this Thesis at...

6. Common Origin Of COMMON ORIGIN OF THE SHOULDER STRUCTURE AND OF THE OSCILLATIONS OF MOMENTS IN MULTIPLICITY DISTRIBUTIONS IN ... ANNIHILATIONS - A. Giovannini; Dip Di Fisica Teorica; S. Lupia; R. Ugoccioni
We show, via a simple parametrization of the multiplicity distribution of charged particles in e + e \Gamma annihilation at the Z 0 peak in terms of the weighted superposition of two negative binomial distributions, that both the shoulder structure in the intermediate multiplicity range and the oscillation in sign of the ratio of factorial cumulants over factorial moments of increasing order are related to hard gluon radiation. Talk presented at the 7th International Workshop "Correlations and Fluctuation" (Nijmegen, The Netherlands, June 30 -- July 6, 1996) and at the 28th International Conference on High Energy Physics -- ICHEP 96...

7. Aspectos algébricos de sistemas dinâmicos - Endler, Antônio
Este trabalho trata o problema genérico da obtenção analítica exata das variedades algébricas que definem domínios de estabilidade e multiestabilidade para sistemas dinâmicos dissipativos com equações de movimento definidas por funções racionais. Apresentamos um método genérico, válido para qualquer sistema dinâmico, que permite reduzir a análise de sistemas multidimensionais arbitrários à análise de um sistema unidimensional equivalente. Este método é aplicado ao mapa de Hénon, o exemplo paradigmático de sistema multidimensional, para estudar a estrutura aritmética imposta pela dinâmica das órbitas de períodos 4, 5, e 6, bem como seus domínios de estabilidade no espaço de parâmetros. Graças à obtençao...

8. Modelo unidimensional do atrito em escala atômica : um estudo por dinâmica molecular - Torres, Evy Augusto Salcedo
o trabalho de Krim e Windom [Phys. Rev B 38, 12184(1988)], que revelou a natureza viscosa do atrito em escala atômica, gerou uma intensa atividade tanto teórica quanto experimental. Contudo, questões fundamentais ainda se matém em aberto com opor exemplo a relação entre o coeficiente de atrito viscoso e a topologia do substrato assim como a dependência com a temperatura do substrato. Neste trabalho apresentamos os resultados, obtidos usando dinâmica molecular, para um modelo unidimensional de um sistema adsorvato/substrato. Pesquisamos diferentes relações de comensuração entre o adsorvato e o substrato assim como também a dependência do coeficiente de atrito fonônico,...

9. SISSA/ISAS Via Beirut 4, 34014 Trieste , Italy and Universit`a di Roma "La Sapienza", Dipartimento di Fisica G10 Teorico P.le Aldo Moro, 00185 Rome, Italy - Pierluigi Contucci
Using the cluster expansion technique, we estimate, uniformly in the volume, the difference between the quenched and annealed free energy in the high temperature phase of a d-dimensional Ising spin glass model with Bernoulli couplings. Classification P.A.C.S. 75.10, 05.50 Letters in Mathematical Physics, N. 27: 143-147, 1993 1 1. Introduction. The study of disordered models in statistical mechanics has not yet reached the stage of systematic treatment. Even physically, the systems described by these models are not yet fully understood. For some of these models it has been rigorously proved [1-4] that in the high temperature phase the quenched and the annealed free energy density coincide in the thermodynamic limit. A question...

10. Grupo de Física Teórica - -

11. Curso de física teórica - Levich, V. G. (Veniamin Grigorevich)

12. Ising model and bernoulli schemes in one dimension - G. Gallavotti; Istituto Di Fisica Teorica
Abstract. We prove that the one-dimensional random fields with finite first moment are isomorphic to Bernoulli schemes.

13. Física teórica, Antipoesía y el Lenguaje del Artefacto - Vásquez Rocca, Adolfo

14. A formação de professores de educação física : amediação dos parâmetros teórico-metodológicos. - Cláudio de Lira Santos Júnior
O estudo insere-se no Programa de Pós-Graduação em Educação da Universidade Federal da Bahia na área de concentração ?Educação, sociedade e práxis pedagógica?, especificamente na linha de pesquisa ?Educação Física & Esporte e Lazer? e no Grupo LEPEL/FACED/UFBA. Tem como objeto de estudo a formação dos professores e os parâmetros teórico-metodológicos. Problematiza a formação apartir da critica as condições de oferecimento dos cursos e da produção do conhecimento cientifico sobre a temática formação de professores nas licenciaturas e na educação física no Brasil. Investiga a base teórico metodológica de três cursos na Bahia, uma instituição particular e duas públicas ?...

15. Curso de física teórica : estadística cuántica y cinética física - Levich, V. G (Veniamin Grigorevich); Vdovin, I.A.; Miamlin, V.A.
84-291-4064-6

16. Laguerre-Sobolev orthogonal polynomials: asymptotics for coherent pairs of type II - Manuel Alfaro; Juan J. Moreno-Balcazar; I Física; Teórica Computacional; M. Luisa Rezola; M. Luisa Rezola
Let Sn be polynomials orthogonal with respect to the inner product (f, g)S = fg d0 + # f # g # d1 where d0 = x e -x dx, d1 = x-# dx + M # # with # > 0, and # > 0. A strong asymptotic on (0, a Mehler-Heine type formula, a Plancherel-Rotach type exterior asymptotic as well as an upper estimate for Sn are obtained. As consequence, we give asymptotic results for the zeros and critical points of Sn and the distribution of contracted zeros. Some numerical examples are shown.

17. Asymptotics of Information Entropies of Some Toda-Like Potentials - J. S. Dehesa; I Física; Teórica Computacional; A. Martínez-finkelshtein; V. N. Sorokin
The spreading of the quantum probability density for the highlyexcited states of a single-particle system with an exponential-type potential on the positive semiaxis is quantitatively determined in both position and momentum spaces by means of the Boltzmann-Shannon information entropy. This problem boils down to the calculation of the asymptotics of the entropy-like integrals of the modified Bessel function of the second kind (also called Mcdonald function or Basset function). The dependence of the two physical entropies on the large quantum number n is given in detail. It is shown that the semiclassical (WKB) position-space entropy grows slower than the corresponding...

18. Observations on staggered fermions at non-zero lattice - Claude Bernard A; Maarten Golterman B; Yigal Shamir C; B Grup De Física Teòrica
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19. Enrico Fermi e Ettore Majorana: continuita' e rinnovamento nell'insegnamento della Fisica teorica - De Gregorio, A.; Esposito, S.
In 1927, just after he obtained a full professorship, Enrico Fermi delivered his first course on Theoretical Physics at the Institute of Physics in Rome. The following year Edoardo Amaldi, Emilio Segre' and Ettore Majorana became students of that course. The lectures given in 1927-28, whose content may be easily reconstructed, probably had a deep impact in forming such young students, who participated actively in the Physics researches carried on in Rome soon after. In this perspective, the case of Ettore Majorana is certainly the most important one: as a lecturer, in 1933-36 he planned to give three advanced Physics courses in Rome, before obtaining his full professorship...

20. Aprendizaje Autodirigido de la Física Teórica en Clave Comunicacional Propuesta de una Nueva Pedagogía - Caballero Hoyos, José Ramiro
Tesis de Maestría en Comunicación

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