arXiv subjects

Hector Vucetich

Publications and source records attributed to Hector Vucetich.

23 records · Page 2Linked to original sources

arXiv1998

Cosmology in a non-standard statistical background

We study the primordial neutron to baryon ratio in a cosmological expanding background within the context of non-extensive statistics, in a fully analytical approach. First order corrections to the weak interaction rates and energy densities in the early universe are obtained and their consequences on the Helium synthesis are analized. We find that, if the nucleosynthesis scenario should be in agreement with observation, this entails a very restrictive bound upon $q$, the non-extensive parameter. We also study some cosmological interesting situations such as the moment of pair annihilation, conserved comoving quantities and derive for the nonextensive statistics, temperature relationships, before and after the removal of pairs.

astro-ph↗

arXiv1997

Steps towards an axiomatic pregeometry of space-time

We present a deductive theory of space-time which is realistic, objective, and relational. It is realistic because it assumes the existence of physical things endowed with concrete properties. It is objective because it can be formulated without any reference to cognoscent subjects or sensorial fields. Finally, it is relational because it assumes that space-time is not a thing but a complex of relations among things. In this way, the original program of Leibniz is consummated, in the sense that space is ultimately an order of coexistents, and time is an order of succesives. In this context, we show that the metric and topological properties of Minkowskian space-time are reduced to relational properties of concrete things. We also sketch how our theory can be extended to encompass a Riemmanian space-time.

gr-qc↗

arXiv1997

Non-Integrability and Chaos in Classical Cosmology

A brief analysis of the dynamics of a Friedmann-Robertson-Walker universe with a conformally coupled, real, self-interacting, massive scalar field, based on the Painleve theory of differential equations, is presented. Our results complete earlier works done within the framework of Dynamical System Theory. We conclude that, in general, the system will not be integrable and that the chaos that has been found in a previous work, arises from the presence of movable logarithmic branch points in the solution in the complex plane of time.

gr-qc↗

arXiv1995

Axiomatic foundations of quantum mechanics revisited: the case for systems

We present an axiomatization of non-relativistic Quantum Mechanics for a system with an arbitrary number of components. The interpretation of our system of axioms is realistic and objective. The EPR paradox and its relation with realism is discussed in this framework. It is shown that there is no contradiction between realism and recent experimental results.

quant-ph↗

arXiv1993

Cosmology, Oscillating Physics and Oscilllating Biology

According to recent reports there is an excess correlation and an apparent regularity in the galaxy one-dimensional polar distribution with a characteristic scale of 128 $h^{-1}$ Mpc. This aparent spatial periodicity can be naturally explained by a time oscillation of the gravitational constant $G$. On the other hand, periodic growth features of bivalve and coral fossiles appear to show a periodic component in the time dependence of the number of days per year. In this letter we show that a time oscillating gravitational constant with similar period and amplitude can explain such a feature.

gr-qc↗