Allan Widom

Resonance damping in ferromagnets and ferroelectrics

A Widom et al. — Wed, 29 Jun 2011 09:47:44 PDT

The phenomenological equations of motion for the relaxation of ordered phases of magnetized and polarized crystal phases can be developed in close analogy with one another. For the case of magnetized systems, the driving magnetic field intensity toward relaxation was developed by Gilbert. For the case of polarized systems, the driving electric field intensity toward relaxation was developed by Khalatnikov. The transport times for relaxation into thermal equilibrium can be attributed to viscous sound wave damping via magnetostriction for the magnetic case and electrostriction for the polarization case.

Electric dipole moments and polarizability in the quark-diquark model of the neutron

Y. N. Srivastava et al. — Fri, 11 Feb 2011 14:50:54 PST

For a bound state internal wave function respecting parity symmetry, it can be rigorously argued that the mean electric dipole moment must be strictly zero. Thus, both the neutron, viewed as a bound state of three quarks, and the water molecule, viewed as a bound state of ten electrons two protons and an oxygen nucleus, both have zero mean electric dipole moments. Yet, the water molecule is said to have a nonzero dipole moment strength $d=e\Lambda $ with $\Lambda_{H_2O} \approx 0.385\ \dot{A}$. The neutron may also be said to have an electric dipole moment strength with $\Lambda_{neutron} \approx 0.612\ fm$. The neutron analysis can be made experimentally consistent, if one employs a quark-diquark model of neutron structure.

Static and dynamic Casimir effect instabilities

Y. N. Srivastava et al. — Fri, 11 Feb 2011 14:50:54 PST

The static Casimir effect concerns quantum electrodynamic induced Lamb shifts in the mode frequencies and thermal free energies of condensed matter systems. Sometimes, the condensed matter constitutes the boundaries of a vacuum region. The static frequency shift effects have been calculated in the one photon loop perturbation theory approximation. The dynamic Casimir effect concerns two photon radiation processes arising from time dependent frequency modulations again computed in the one photon loop approximation. Under certain conditions the one photon loop computation may become unstable and higher order terms must be invoked to achieve stable solutions. This stability calculation is discussed for a simple example dynamical Casimir effect system.

Dynamic time scales in colored glass nuclear matter

V. Parihar et al. — Fri, 11 Feb 2011 14:50:53 PST

In Ultra high energy collisions, the concept of a glass law is invoked in the framework of 'low tension' QCD strings. It is shown that the excitation of QCD strings at low energy has a negative temperature and at high energy has a positive temperature always higher than the Hagedorn temperature, T_H. Very high energy strings T->T_H + 0+ move very slowly as a viscous melted glass with very high viscosity. However, in a very short collision time, it is difficult to transfer the initial collision kinetic energy into the internal energy of a few strings. The low energy strings at high T>>T_H have a low viscosity giving rise to an almost perfect fluid. The role of strings in a nucleus is closely analogous to the role of polymer chains in some viscous glass beads.

Electron neutrino sources from the core of the earth

A. Widom et al. — Fri, 11 Feb 2011 14:50:52 PST

The physical interpretation of extensive measurements of electron neutrinos (in laboratories located on or somewhat below the Earth's surface) often require geophysical notions concerning the possible neutrino sources. Here, we discuss the notion that the Earth's core is a substantial source of low energy electron neutrinos.

Energetic electrons and nuclear transmutations in exploding wires

A. Widom et al. — Fri, 11 Feb 2011 14:50:51 PST

Nuclear transmutations and fast neutrons have been observed to emerge from large electrical current pulses passing through wire filaments which are induced to explode. The nuclear reactions may be explained as inverse beta transitions of energetic electrons absorbed either directly by single protons in Hydrogen or by protons embedded in other more massive nuclei. The critical energy transformations to the electrons from the electromagnetic field and from the electrons to the nuclei are best understood in terms of coherent collective motions of the many flowing electrons within a wire filament. Energy transformation mechanisms have thus been found which settle a theoretical paradox in low energy nuclear reactions which has remained unresolved for over eight decades. It is presently clear that nuclear transmutations can occur under a much wider range of physical conditions than was heretofore thought possible.

Electronic transport in oxygen deficient ferromagnetic semiconducting TiO$_{2-\delta}$

Soack Dae Yoon et al. — Fri, 11 Feb 2011 14:50:51 PST

TiO$_{2-\delta}$ films were deposited on (100) Lanthanum aluminates LaAlO$_{3}$ substrates at a very low oxygen chamber pressure $P\approx 0.3$ mtorr employing a pulsed laser ablation deposition technique. In previous work, it was established that the oxygen deficiency in these films induced ferromagnetism. In this work it is demonstrated that this same oxygen deficiency also gives rise to semiconductor titanium ion impurity donor energy levels. Transport resistivity measurements in thin films of TiO$_{2-\delta}$ are presented as a function of temperature and magnetic field. Magneto- and Hall- resistivity is explained in terms of electronic excitations from the titanium ion donor levels into the conduction band.

Electronic enhancements in the detection of gravitational waves by metallic antennae

Y. N. Srivastava et al. — Fri, 11 Feb 2011 14:50:50 PST

For mechanical Weber gravitational wave antennae, it is thought that gravity waves are weakly converted into acoustic vibrations. Acoustic vibrations in metals (such as Aluminum) are experimentally known to be attenuated by the creation of electron-hole pairs described via the electronic viscosity. These final state electronic excitations give rise to gravitational wave absorption cross sections which are considerably larger (by four orders of magnitude) than those in previous theories which have not explicitly considered electronic excitations.

Electronic detection of gravitational disturbances and collective coulomb interactions

A Widom et al. — Fri, 11 Feb 2011 14:50:49 PST

The cross section for a gravitational wave antenna to absorb a graviton may be directly expressed in terms of the non-local viscous response function of the metallic crystal. Crystal viscosity is dominated by electronic processes which then also dominate the graviton absorption rate. To compute this rate from a microscopic Hamiltonian, one must include the full Coulomb interaction in the Maxwell electric field pressure and also allow for strongly non-adiabatic transitions in the electronic kinetic pressure. The view that the electrons and phonons constitute ideal gases with a weak electron phonon interaction is not sufficiently accurate for estimating the full strength of the electronic interaction with a gravitational wave.

Dispersive techniques for $\alpha_s$, $R_{had}$ and instability of the perturbative vacuum

Y. Srivastava et al. — Fri, 11 Feb 2011 14:50:48 PST

Recent dispersive techniques developed by us are applied to discuss three problems: 1. A long standing discrepan-cy between the measurements of $R(s)$ for $\sqrt{s} = (5\div 7.5)GeV$ by Crystal Ball and MARK I has been analyzed and its consequences analyzed for the number of contributing quarks. 2. Noting that the perturbative $\alpha_s$ has the wrong analyticity, analytic models consistent with asymptotic freedom (AF) and confinement have been constructed and applied to discuss $\tau$ decay. 3. It is shown that AF leads to a wrong sign for $\im\big(\alpha(s)\big)$ which signals an instability of the perturbative QCD vacuum.

Electric field effects and the experimental value of the muon g-2 anomaly

A. Widom et al. — Fri, 11 Feb 2011 14:50:47 PST

The electric field corrections to the recently measured muon magnetic moment g-2 anomaly are considered from both the classical (BMT) and the quantum mechanical (Dirac) viewpoints. In both views, we prove that the electric field inducing the horizontal betatron tune does not renormalize the anomaly frequency. With this result kept in mind, the experimental muon magnetic moment anomaly is in closer agreement with standard model predictions than has been previously reported.

Classical Hamiltonian dynamics and Lie group algebras

B. Aycock et al. — Mon, 31 Jan 2011 08:24:00 PST

The classical Hamilton equations of motion yield a structure sufficiently general to handle an almost arbitrary set of ordinary differential equations. Employing elementary algebraic methods, it is possible within the Hamiltonian structure to describe many physical systems exhibiting Lie group symmetries. Elementary examples include magnetic moment precession and the mechanical orbits of color charged particles in classical non-abelian chromodynamics.

Classical analytical mechanics and entropy production

J. Silverberg et al. — Mon, 31 Jan 2011 08:23:59 PST

The usual canonical Hamiltonian or Lagrangian formalism of classical mechanics applied to macroscopic systems describes energy conserving adiabatic motion. If irreversible diabatic processes are to be included, then the law of increasing entropy must also be considered. The notion of entropy then enters into the general classical mechanical formalism. The resulting general formulation and its physical consequences are explored.

Atomic scale fractal dimensionality in proteins

Duccio Medini et al. — Mon, 31 Jan 2011 08:23:58 PST

The soft condensed matter of biological organisms exhibits atomic motions whose properties depend strongly on temperature and hydration conditions. Due to the superposition of rapidly fluctuating alternative motions at both very low temperatures (quantum effects) and very high temperatures (classical Brownian motion regime), the dimension of an atomic "path" is in reality different from unity. In the intermediate temperature regime and under environmental conditions which sustain active biological functions, the fractal dimension of the sets upon which atoms reside is an open question. Measured values of the fractal dimension of the sets on which the Hydrogen atoms reside within the Azurin protein macromolecule are reported. The distribution of proton positions was measured employing thermal neutron elastic scattering from Azurin protein targets. As the temperature was raised from low to intermediate values, a previously known and biologically relevant dynamical transition was verified for the Azurin protein only under hydrated conditions. The measured fractal dimension of the geometrical sets on which protons reside in the biologically relevant temperature regime is given by D = 0.65±0.1. The relationship between fractal dimensionality and biological function is qualitatively discussed.

Correlated hip motions during quiet standing

R. K. Koleva et al. — Mon, 31 Jan 2011 08:23:57 PST

Kinematic measurements of two simultaneous coordinates from postural sway during quiet standing were performed employing multiple ultrasonic transducers. The use of accurate acoustic devices was required for the detection of the small random noise displacements. The trajectory in the anteroposterior - mediolateral plane of human chest was measured and compared with the trajectory in anteroposterior direction from the upper and lower body. The latter was statistically analyzed and appeared to be strongly anti-correlated. The anticorrelations represent strong evidence for the dominance of hip strategy during an unperturbed one minute stance. That the hip strategy, normally observed for large amplitude motions, also appears in the small amplitude of a quite stance, indicates the utility of such noise measurements for exploring the biomechanics of human balance.

Acuasal behavior in quantum electrodynamics

A. Widom et al. — Mon, 31 Jan 2011 08:23:56 PST

Acausal features of quantum electrodynamic processes are discussed. While these processes are not present for the classical electrodynamic theory, in the quantum electrodynamic theory, acausal processes are well known to exist. For example, any Feynman diagram with a "loop" in space-time describes a "particle" which may move forward in time or backward in time or in space-like directions. The engineering problems involved in experimentally testing such causality violations on a macroscopic scale are explored.

Absorption of nuclear gamma radiation by heavy electrons on metallic hydride surfaces

A. Widom et al. — Mon, 31 Jan 2011 08:23:55 PST

Low energy nuclear reactions in the neighborhood of metallic hydride surfaces may be induced by ultra-low momentum neutrons. Heavy electrons are absorbed by protons or deuterons producing ultra low momentum neutrons and neutrinos. The required electron mass renormalization is provided by the interaction between surface electron plasma oscillations and surface proton oscillations. The resulting neutron catalyzed low energy nuclear reactions emit copious prompt gamma radiation. The heavy electrons which induce the initially produced neutrons also strongly absorb the prompt nuclear gamma radiation, re-emitting soft photons. Nuclear hard photon radiation away from the metallic hydride surfaces is thereby strongly suppressed.

Compact lattice QED and the Coulomb potential

Y. N. Srivastava et al. — Mon, 31 Jan 2011 08:23:55 PST

The potential energy of a static charge distribution on a lattice is rigorously computed in the standard compact quantum electrodynamic model. The method used follows closely that of Weyl for ordinary quantum electrodynamics in continuous space-time. The potential energy of the static charge distribution is independent of temperature and can be calculated from the lattice version of Poisson’s equation. It is the usual Coulomb potential.

Breakdown of the KLN theorem for charged particles in condensed matter

Y. N. Srivastava et al. — Mon, 31 Jan 2011 08:23:54 PST

The Kinoshita-Lee-Nauenberg (KLN) theorem describes the fact that inclusive electromagnetic and weak production processes in the vacuum do not contain singularities in the ultra-relativistic limit of zero mass. When these production processes occur in condensed matter, the KLN theorem fails. One consequence of this failure is that precision lifetime determinations of stopped muons will depend on the nature of the surrounding material.

Causality and electromagnetic transmissions through materials

V. Kidambi et al. — Mon, 31 Jan 2011 08:23:53 PST

There have been several experiments which hint at evidence for superluminal transport of electromagnetic energy through a material slab. On the theoretical side, it has appeared evident that acausal signals are indeed possible in quantum electrodynamics. However, it is unlikely that superluminal signals can be understood on the basis of a purely classical electrodynamic signals passing through a material. The classical and quantum theories represent quite different views, and it is the quantum view which may lead to violations of Einstein causality.