University of São Paulo

About: University of São Paulo is a education organization based out in São Paulo, Brazil. It is known for research contribution in the topics: Population & Health care. The organization has 136513 authors who have published 272320 publications receiving 5127869 citations. The organization is also known as: USP & Universidade de São Paulo.

Sterile neutrino oscillations: the global picture

Abstract: Neutrino oscillations involving eV-scale neutrino mass states are investigated in the context of global neutrino oscillation data including short and long-baseline ac- celerator, reactor, and radioactive source experiments, as well as atmospheric and solar neutrinos. We consider sterile neutrino mass schemes involving one or two mass-squared dierences at the eV 2 scale denoted by 3+1, 3+2, and 1+3+1. We discuss the hints for

Model of the Causal Interpretation of Quantum Theory in Terms of a Fluid with Irregular Fluctuations

Abstract: In this paper, we propose a physical model leading to the causal interpretation of the quantum theory. In this model, a set of fields which are equivalent in many ways to a conserved fluid, with density ${|\ensuremath{\psi}|}^{2}$, and local stream velocity, $\frac{d\ensuremath{\xi}}{\mathrm{dt}}=\frac{\ensuremath{ abla}S}{m}$, act on a particle-like inhomogeneity which moves with the local stream velocity of the equivalent fluid. By introducing the hypothesis of a very irregular and effectively random fluctuation in the motions of the fluid, we are able to prove that an arbitrary probability density ultimately decays into ${|\ensuremath{\psi}|}^{2}$. Thus, we answer an important objection to the causal interpretation, made by Pauli and others. This result is extended to the Dirac equation and to the many-particle problem.

Efficient and provably-secure identity-based signatures and signcryption from bilinear maps

Abstract: In this paper we describe a new identity-based signcryption (IBSC) scheme built upon bilinear maps. This scheme turns out to be more efficient than all others proposed so far. We prove its security in a formal model under recently studied computational assumptions and in the random oracle model. As a result of independent interest, we propose a new provably secure identity-based signature (IBS) scheme that is also faster than all known pairing-based IBS methods.