3 resultados para Non-relativistic scattering theory
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Considering a non-relativistic ideal gas, the standard foundations of kinetic theory are investigated in the context of non-gaussian statistical mechanics introduced by Kaniadakis. The new formalism is based on the generalization of the Boltzmann H-theorem and the deduction of Maxwells statistical distribution. The calculated power law distribution is parameterized through a parameter measuring the degree of non-gaussianity. In the limit = 0, the theory of gaussian Maxwell-Boltzmann distribution is recovered. Two physical applications of the non-gaussian effects have been considered. The first one, the -Doppler broadening of spectral lines from an excited gas is obtained from analytical expressions. The second one, a mathematical relationship between the entropic index and the stellar polytropic index is shown by using the thermodynamic formulation for self-gravitational systems
Resumo:
Kindergarten teachers training gains the spotlight with the passing of Law number 9.394/96 (Guidelines and Basis Law) that defines this segment as the initial step of basic education, with pedagogical function. In this spectrum, the discussion about teacher training unravels to ensure social quality to education as well as the teacher s specificities towards child singularities. Adding to that, the growing propagation of Pedagogy in an undergraduate level, given that such course has been continually transformed by the National Curriculum Guidelines for Pedagogy (2006), highlighting the addition of curriculum components that are specific to upbringing. The complex debate circa kindergarten teachers training has advancements and hardships that need to be unveiled in order to improve both formation and social quality of education in the 0- 5 years old range. This investigation inserts itself in said context and aims to analyze which knowledge, specific to kindergarten teaching are constructed, according to undergraduate trainees, in Pedagogy s supervised internship. The study was conducted alongside the discipline: Supervised Internship in Child Education ministered by the Advanced Campus of Rio Grande do Norte s State University s in the municipality of Patu-RN (CAP-UERN-Patu) and was conducted through 2012 by accompanying four undergraduate interns. We first assumed that the development of teaching knowledge is a complex process of appropriation of cultural-social practices and is symbolically mediated by interactions that occur in the formation context, and the supervised internship can be understood as a space for the articulation and enlargement of theoretical and practical knowledge, directly related to the specificities of child education. The theoretical-methodological foundation was based upon the historiccultural approach of L. S. Vygotsky and M. Bakhtin s dialogism on human sciences research, as well as his postulates on learning and developmental processes, conceived as both essentially social and discursive. The investigation approached the principles of the qualitative perspective and to the construction and analysis of data, involved documental analysis and, specially, semi-structured interviews, both individual and collective, whose fundamental premise was the production-comprehension of meanings in a dialogical perspective. The participants texts/speeches produced a synthesis that points to the occurrence, within the supervised internship at CAP/UERN, of internalization/appropriation processes and, as such, of formulation of meanings that are pertinent to child education: child, childhood, kindergarten and teacher signification and this stage s specific teaching knowledge. It stood out that the internship, alongside other curriculum components, is, in fact, one of the primeval formation environment for the teachers, in which the interns interact with their colleagues, supervisor professor, collaborator professor, and of course, the children to construct their erudition. Such interactions allow the undergraduate interns to develop attitudes and procedures to reflect on what they know, what they ve done and what they can achieve. We have concluded that the undergraduate internship can constitute itself as an articulatorconsolidator environment in the future teacher s formation process and, since well oriented, can provide the effective initiation, not only to the practice, but to the praxis as a movement of non dissociability between theory and practice
Resumo:
The recent astronomical observations indicate that the universe has null spatial curvature, is accelerating and its matter-energy content is composed by circa 30% of matter (baryons + dark matter) and 70% of dark energy, a relativistic component with negative pressure. However, in order to built more realistic models it is necessary to consider the evolution of small density perturbations for explaining the richness of observed structures in the scale of galaxies and clusters of galaxies. The structure formation process was pioneering described by Press and Schechter (PS) in 1974, by means of the galaxy cluster mass function. The PS formalism establishes a Gaussian distribution for the primordial density perturbation field. Besides a serious normalization problem, such an approach does not explain the recent cluster X-ray data, and it is also in disagreement with the most up-to-date computational simulations. In this thesis, we discuss several applications of the nonextensive q-statistics (non-Gaussian), proposed in 1988 by C. Tsallis, with special emphasis in the cosmological process of the large structure formation. Initially, we investigate the statistics of the primordial fluctuation field of the density contrast, since the most recent data from the Wilkinson Microwave Anisotropy Probe (WMAP) indicates a deviation from gaussianity. We assume that such deviations may be described by the nonextensive statistics, because it reduces to the Gaussian distribution in the limit of the free parameter q = 1, thereby allowing a direct comparison with the standard theory. We study its application for a galaxy cluster catalog based on the ROSAT All-Sky Survey (hereafter HIFLUGCS). We conclude that the standard Gaussian model applied to HIFLUGCS does not agree with the most recent data independently obtained by WMAP. Using the nonextensive statistics, we obtain values much more aligned with WMAP results. We also demonstrate that the Burr distribution corrects the normalization problem. The cluster mass function formalism was also investigated in the presence of the dark energy. In this case, constraints over several cosmic parameters was also obtained. The nonextensive statistics was implemented yet in 2 distinct problems: (i) the plasma probe and (ii) in the Bremsstrahlung radiation description (the primary radiation from X-ray clusters); a problem of considerable interest in astrophysics. In another line of development, by using supernova data and the gas mass fraction from galaxy clusters, we discuss a redshift variation of the equation of state parameter, by considering two distinct expansions. An interesting aspect of this work is that the results do not need a prior in the mass parameter, as usually occurs in analyzes involving only supernovae data.Finally, we obtain a new estimate of the Hubble parameter, through a joint analysis involving the Sunyaev-Zeldovich effect (SZE), the X-ray data from galaxy clusters and the baryon acoustic oscillations. We show that the degeneracy of the observational data with respect to the mass parameter is broken when the signature of the baryon acoustic oscillations as given by the Sloan Digital Sky Survey (SDSS) catalog is considered. Our analysis, based on the SZE/X-ray data for a sample of 25 galaxy clusters with triaxial morphology, yields a Hubble parameter in good agreement with the independent studies, provided by the Hubble Space Telescope project and the recent estimates of the WMAP