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Michael J. Caola

Publications and source records attributed to Michael J. Caola.

4 recordsLinked to original sources

A simple direct quantum model which, with no random phase assumptions and with arbitrary initial conditions, evolves to the Boltzman distribution

We consider M systems (each an electron in a long square cylinder) uniformly arranged on a ring and with Coulomb interactions. Exact straightforward numerical time-dependent perturbation calculation of a single N-level ($\lesssim 7$) system, with no (random) phase assumptions, system show a Boltzman distribution. We exploit the physical ring symmetry and develop several hierarchical physical equation set so of increasing generality and (computation) speed. Given the impressive history of theoretical quantum-mehanical statistical mechanics, our results might seem surprising, but we observe that accurate calculation of correct physical equations should mimic Nature.

physics.gen-ph↗

DNA and the double helix: statistical equilibrium and Neumann's principle

Neumann's principle (that the symmetry of a crystal measurement cannot be lower than that of its point-group) is a corner- stone of crystallography: were it false, then the technique of x-ray diffraction (double-helix, DNA) might well not exist. The literature variously regards its truth as obvious, intuitive, axiomatic or even impossible [10], without further analysis or proof. After identifying and correcting a false lead/start, we give a plausible proof of Neumann's principle, using group theory and quantum statistical mechanics.

cond-mat.stat-mech↗

Radiative transfer in a spherical, emitting, absorbing and anisotropically scattering medium

The atmospheres of planets (including Earth) and the outer layers of stars have often been treated in radiative transfer as plane-parallel media, instead of spherical shells, which can lead to inaccuracy, e.g. limb darkening. We give an exact solution of the radiative transfer specific intensity at all points and directions in a finite spherical medium having arbitrary radial spectral distribution of: source (temperature), absorption, emission and anisotropic scattering. The power and efficiency of the method stems from the spherical numerical gridding used to discretize the transfer equations prior to matrix solution: the wanted ray and the rays which scatter into it both have the same physico-geometric structure. Very good agreement is found with an isotropic astrophysical benchmark (Avrett & Loeser, 1984). We introduce a specimen arbitrary forward-back-side phase scattering function for future comparisons. Our method directly and exactly addresses spherical symmetry with anisotropic scattering, and could be used to study the Earth's climate, nuclear power (neutron diffusion) and the astrophysics of stars and planets.

cond-mat.stat-mech↗

A prime prime primer

We present a simple, closed formula which gives all the primes in order. It is a simple product of integer floor and ceiling functions.

math.GM↗