Reproducing neutrino effects on the matter power spectrum through a degenerate Fermi gas approach

Autor(es)

Perico, E. L. D. ; Bernardini, A. E.

• Tipo de documento: Artigo Científico
• Fonte: Journal of Cosmology and Astroparticle Physics; v. N/A, n. 6, p. 22-pg., 2011-06-01.

Resumo

Modifications on the predictions about the matter power spectrum based on the hypothesis of a tiny contribution from a degenerate Fermi gas (DFG) test-fluid to some dominant cosmological scenario are investigated. Reporting about the systematic way of accounting for all the cosmological perturbations, through the Boltzmann equation we obtain the analytical results for density fluctuation, delta, and fluid velocity divergence, theta, of the DFG. Small contributions to the matter power spectrum are analytically obtained for the radiation-dominated background, through an ultra-relativistic approximation, and for the matter-dominated and A-dominated eras, through a non-relativistic approximation. The results can be numerically reproduced and compared with those of considering non-relativistic and ultra-relativistic neutrinos into the computation of the matter power spectrum. Lessons concerning the formation of large scale structures of a DFG are depicted, and consequent deviations from standard ACDM predictions for the matter power spectrum (with and without neutrinos) are quantified. (AU)

• Processo FAPESP: 08/50671-0 - Aplicações em mecânica quântica relativística e teoria de campos: oscilações quânticas, campos fermiônicos, quiralidade e equação de Dirac; sistemas com violação de Lorentz, energia escura e neutrinos cosmológicos; dinâmica relativística no efeito de tunelamento; zitterbewegung-like em sistemas fermiônicos em física da matéria condensada
• Beneficiário: Alex Eduardo de Bernardini
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores