Searcharxiv⌕ Search

arXiv subjects

J. M. F. Bassalo

Publications and source records attributed to J. M. F. Bassalo.

16 recordsLinked to original sources
arXiv2013

Time-Dependent Gaussian Solution for the Kostin Equation around Classical Trajectories

The structure of time-dependent Gaussian solutions for the Kostin equation in dissipative quantum mechanics is analyzed. Expanding the generic external potential near the center of mass of the wave packet, one conclude that: the center of mass follows the dynamics of a classical particle under the external potential and a damping proportional to the velocity; the width of the wave packet satisfy a non-conservative Pinney equation. An appropriate perturbation theory is developed for the free particle case, solving the long standing problem of finding analytic expressions for square integrable solutions of the free Kostin equation. The associated Wigner function is also studied.

quant-ph↗
arXiv2010

Theoretical SAXS Analysis of Structures of Disordered Gold Polymer Thin Films

Recently the structure of disordered gold-polymer(PMMA-Au) thin films have been measured using Small Angle X-ray Scattering (SAXS). We have analyzed these experimental results using the fractal SAXS theory. The films are formed of polymer-embedded gold nanoclusters and were fabricated by very low energy gold ion implantation into PMMA (polymethylmethacrylate). The composite films span (with dose variation) the transition from electrically insulating to electrically conducting regimes, a range of interest fundamentally and technologically. We find excellent agreement with theory, and show that the PMMA-Au films have monodispersive or polydispersive characteristics depending on the implanted ion dose. Keywords: SAXS theory, Fractality, percolation, correlation effects.

cond-mat.dis-nn↗
arXiv2009

Weak Interactions ,Tunneling Racemization and Chiral Stability

We study in the framework of the Schrodinger equation the effect of intermolecular interactions on the tunneling racemization of the active molecule. The active molecule is assumed as a two-level system and the left-right isomerism is viewed in terms of a double-bottomed harmonic potential well. The active molecule is assumed to be embedded in a gas, liquid or solid, submitted to a perturbing potential U created by the molecules of the sample. In our model we take into account the difference of energy E due to the weak interactions between the left (L) and right (R) configurations. We have shown that when E is equal to zero the system cannot be optically stable: the optical activity tends asymptotically to zero in the case of dilute gases or compressed gases and liquids or oscillates periodically around zero when the molecules are isolated or submitted to a static potential. Only when E is different of zero the system can be optically stable depending on the strength parameters of the potential U and on the magnitude of the spontaneous tunneling.

quant-ph↗
arXiv2009

Optical Activity of a Dilute Dielectric Medium: Pasteur and the Molecular Symmetries

In 1848 Pasteur conjectured that the rotation of the polarization plane of the light in a dilute dielectric medium is generated by the molecular symmetries of the medium where the light propagates. Our objective is to show that Pasteur hypothesis was correct using basic knowledge of electromagnetism and quantum mechanics. In Sections 2-5 we present a brief review of the fundamental concepts of the electromagnetism necessary to study the optical activity. In Sections 6-8 using the quantum mechanical perturbation theory and taking into account the molecular symmetries we calculate the optical activity of the medium. It will be shown that the theoretical predictions that are in good agreement with the experimental results give support to the Pasteur hypothesis.

quant-ph↗
arXiv2009

The Ramsauer-Townsend Effect and the de Broglie-Bohm Quantum Mechanics

In this work we study the Ramsauer-Townsend effect.First, we use the Quantum Mechanical Formalism of Schrodinger. After, it is calculated with the Quantum Mechanical Formalism of de Broglie-Bohm. In this case, we use the Kostin equation, taking into account the energy dissipation of the electrons scattered by sharp edged potential wells.

quant-ph↗
arXiv2009

Intermediate Statistics, Parastatistics, Fractionary Statistics and Gentileonic Statistics

We made in this paper a brief analysis of the following statistics: Intermediate Statistics, Parastatistics, Fractionary Statistics and Gentileonic Statistics that predict the existence of particles which are different from bosons, fermions and maxwellons. We shown the fundamental hypothesis assumed in each one of the above mentioned statistics and their main predictions and compared them with experimental results. Taking into account the works done about these statistics we could say that there is a tendency to believe that real particles, that is, those that can be observed freely, can be only bosons, fermions and maxwellons and that all other particles, different from these would be quasiparticles. Up to date in 3-dim systems only bosons, fermions and maxwellons have been detected freely. Recently in 2-dim systems have been detected the quasiparticles named anyons that have fractionary charges and spins.

cond-mat.stat-mech↗
arXiv2009

Could Adrenaline Positive Help to Prevent Psychosomatic Illnesses ?

Although the existence of a cause and effect relationship between emotions and Psychosomatic Illnesses (manifestation of organic diseases produced by emotional problems) is an unquestionable fact, yet it remains to be explained the mechanism by which an emotion affects the cure or worsening of an illness. In this paper we will examine some articles written by doctors and psychologists which confirm the Prevention Effect (or even cure) of such illnesses, and hypothesize that this cause and effect relationship is mediated by a substance, D (+) - adrenaline, which is one of the enantiomers [1] of the adrenaline molecule.

physics.med-ph↗