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2016_regimento_interno_cbpf.pdf.jpgRegimento interno do Centro Brasileiro de Pesquisas Físicas: 2016-Centro Brasileiro de Pesquisas Físicas (CBPF)-
2020_regimento_interno_cbpf.pdf.jpgRegimento interno do Centro Brasileiro de Pesquisas Físicas: 2020-Centro Brasileiro de Pesquisas Físicas (CBPF)-
2022_regimento_interno_cbpf.pdf.jpgRegimento interno do Centro Brasileiro de Pesquisas Físicas: 2022-Centro Brasileiro de Pesquisas Físicas (CBPF)-
Relativeca dopplera efekto ce unuforme akcelata movo - III: efeito doppler relativa em um movimento uniforme acelerado - IIIPaiva, Filipe de Moraes; Teixeira, Antônio Fernandes da FonsecaCentro Brasileiro de Pesquisas Físicas (CBPF)Ce special-relativeco ni detale priskribas lum-Doppleran efikon inter restanta lum-fonto kaj observanto kun rektlinia movado kaj konstanta propra akcelo -- Na relatividade especial, nós descrevemos detalhadamente o efeito Doppler luminoso entre uma fonte em repouso e um observador com movimento retilíneo e aceleração própria constante.
Self-Interacting Electromagnetic Fields and a Classical Discussion on the Stability of the Electric ChargeVelloso, Sergio de Oliveira; Helayel Neto, José Abdalla; Smith, Alexander Willian; Assis, L. P. G de (Leonardo Paulo Guimarães de Assis)Centro Brasileiro de Pesquisas Físicas (CBPF)The present work proposes a discussion on the self-energy of charged particles in the framework of nonlinear electrodynamics. We seek magnetically stable solutions generated by purely electric charges whose electric and magnetic fields are computed as solutions to the Born-Infeld equations. The approach yields rich internal structures that can be described in terms of the physical fields with explicit analytic solutions. This suggests that the anomalous field probably originates from a magnetic excitation in the vacuum due to the presence of the very intense electric field. In addition, the magnetic contribution has been found to exert a negative pressure on the charge. This, in turn, balances the electric repulsion, in such a way that the self-interaction of the field appears as a simple and natural classical mechanism that is able to account for the stability of the electron charge.
Stochastic quantization for complex actionsMenezes, Gabriel; Svaiter, Nami FuxCentro Brasileiro de Pesquisas Físicas (CBPF)We use the stochastic quantization method to study systems with complex valued path integral weights. We assume a Langevin equation with a memory kernel and Einstein's relations with colored noise. The equilibrium solution of this non-Markovian Langevin equation is analyzed. We show that for a large class of elliptic non-Hermitian operators acting on scalar functions on Euclidean space, which define different models in quantum field theory, converges to an equilibrium state in the asymptotic limit of the Markov parameter. Moreover, as we expected, we obtain the Schwinger functions of the theory.
SUSY shape-invariant hamiltonians for the generalized dirac-coulomb problemRodrigues, R. de Lima (Rafael); Vaidya, Arvind NarayanCentro Brasileiro de Pesquisas Físicas (CBPF)A spin 1/2 relativisc particle described by a general potential in terms of the sum of the coulomb potential with a lorentz scalar potential is investigated via supersymmetry in quantum mechanics
The three-dimensionality of the Universe : a reason for the existence of chemists and beyondCaruso., F.Brasil. Ministério da Ciência, Tecnologia, Inovações e Comunicações (MCTIC); Centro Brasileiro de Pesquisas Físicas (CBPF)A general sketch of how the problem of space dimensionality depends on Anthropic arguments is presented. In particular, the influence of three-dimensionality on the stability of the solar system and on the origin of life on Earth is reviewed. A new constraint on space dimensionality and on its invariance in a very large time and spatial scales is proposed.
Time and space deformations in special relativity and measuring unitsde Oliveira., Alfredo MarquesCentro Brasileiro de Pesquisas Físicas (CBPF)Change of clock rates and the deformation of solid bodies following relativistic transformation between inertial reference systems are discussed under the principles of the physical theory of measurements. Both, time dilation and contraction of rods, are interpreted as being the result of measurements done under different unit standards rather than as a consequence of any physical action born in relative motion. The choice of units is not arbitrary but fixed by metric information contained in a light signal observed under the conditions of the transverse Doppler effect.