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M. Cattani

Publications and source records attributed to M. Cattani.

30 records · Page 2Linked to original sources

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↗

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↗

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↗

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↗

Insulator-Conductor Transition: A Brief Theoretical Review

The electrical conductivity of disordered insulator-conductor composites have been studied for more than thirty years. In spite of this some properties of dc bulk conductivity of composites still remain incompletely understood. We present a brief review of the most significant theories that have been proposed to study the critical insulator-conductor transition comparing their predictions with many experimental results.

physics.atm-clus↗

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↗

Deformation of Rapidly Rotating Compact Stars

We have developed a numerical code to study the deformation ($\varepsilon = (I_{zz}-I_{xx})/I_{zz}$, where $I_{ii}$ are the moments of inertia) of neutron stars in rapidly rotation in a fully general relativistic calculation. We have found that the deformation is larger, depending on the angular velocity, than is generally assumed for gravitational wave estimations. Calculations were performed by employing the Bethe-Johnson I EOS (equation of state) and a new set of models by the Frankfurt group including $Λ$ hyperons for several choices of their coupling constants to ordinary nucleons. Possible implications for gravitational wave searches are briefly discussed.

astro-ph↗

Gravitational Waves from Wobbling Pulsars

The prospects for detection of gravitational waves from precessing pulsars have been considered by constructing fully relativistic rotating neutron star models and evaluating the expected wave amplitude $h$ from a galactic source. For a "typical" neutron matter equation of state and observed rotation rates, it is shown that moderate wobble angles may render an observable signal from a nearby source once the present generation of interferometric antennas becomes operative.

astro-ph↗