title:
Benchmark ab initio thermochemistry of the isomers of diimide, N_2H_2,
  using accurate computed structures and anharmonic force fields

abstract:
  A benchmark ab initio study on the thermochemistry of the trans-HNNH,
cis-HNNH, and H$_2$NN isomers of diazene has been carried out using the CCSD(T)
coupled cluster method, basis sets as large as $[7s6p5d4f3g2h/5s4p3d2f1g]$, and
extrapolations towards the 1-particle basis set limit. The effects on
inner-shell correlation and of anharmonicity in the zero-point energy were
taken into account: accurate geometries and anharmonic force fields were thus
obtained as by-products. Our best computed $\Delta H^\circ_{f,0}$ for
trans-HNNH, 49.2 \pm 0.3 kcal/mol, is in very good agreement with a recent
experimental lower limit of 48.8 \pm 0.5 kcal/mol. CCSD(T) basis set limit
values for the isomerization energies at 0 K are 5.2 \pm 0.2 kcal/mol
(cis-trans) and 24.1 \pm 0.2 kcal/mol (iso-trans). Our best computed geometry
for trans-HNNH, $r_e$(NN)=1.2468 \AA, $r_e$(NH)=1.0283 \AA, and
$\theta_e$=106.17$^\circ$, reproduces the precisely known ground-state
rotational constants of trans-HNNH to within better than 0.1 %. The
rotation-vibration spectra of both cis-HNNH and H$_2$NN are dominated by very
strong Coriolis and Fermi resonances. In addition, the NH stretches in H$_2$NN
are so strongly anharmonic that vibrational perturbation theory breaks down,
and the molecule appears to be an excellent test case for variational
treatments of the vibrational Schr\"odinger equation.


title:
Application of the time-dependent local-density approximation to
  conjugated molecules

abstract:
  The time-dependent local-density approximation (TDLDA) is applied to the
optical response of conjugated carbon molecules in the energy range of 0-30 eV,
with calculations given for carbon chains, polyenes, retinal, benzene and C_60.
The major feature of the spectra, the collective pi-pi* transition, is seen at
energies ranging from below 2 to 7 eV, and is reproduced by the theory to a few
tenths of an eV with a good account of systematic trends. However, there is
some indication that TDLDA predicts too much fragmentation of the strength
function in large molecules. Transition strengths are reproduced with a typical
accuracy of 20%. The theory also predicts a broad absorption peak in the range
15-25 eV, and this feature agrees with experiment in the one case where
quantitative data is available (benzene).


title: Towards the Observation of Signal over Background in Future Experiments

abstract:
  We propose a method to estimate the probability of new physics discovery in
future high energy physics experiments. Physics simulation gives both the
average numbers $<N_b>$ of background and $<N_s>$ of signal events. We find
that the proper definition of the significance for $<N_b>, <N_s> \gg 1$ is
$S_{12} = \sqrt{<N_s>+<N_b>} - \sqrt{<N_b>}$ in comparison with often used
significances $S_1 = <N_s>/\sqrt{<N_b>}$ and $S_2 = <N_s>/\sqrt{<N_s> +
<N_b>}$. We also propose a method for taking into account the systematical
errors related to nonexact knowledge of background and signal cross sections.
An account of such systematics is very essential in the search for
supersymmetry at LHC.


title:
Ab initio calculations with a nonspherical Gaussian basis set: Excited
  states of the hydrogen molecule

abstract:
  A basis set of generalized nonspherical Gaussian functions (GGTOs) is
presented and discussed. As a first example we report on Born-Oppenheimer
energies of the hydrogen molecule. Although accurate results have been
obtained, we conclude that H_2 is too 'simple' to allow for a substantial gain
by using nonspherical functions. We rather expect that these functions may be
particularly useful in calculations on large systems. A single basis set of
GGTOs was used to simultaneously calculate the potential energy curves of
several states within each subspace of {1,3}\Sigma_{g,u} symmetry. We hereby
considerd the entire region of internuclear distances 0.8 < R < 1000 a.u. In
particular the results for the fourth up to sixth electronic states show a high
accuracy compared to calculations which invoke explicitely correlated
functions, e.g. the relative accuracy is at least of the order of magnitude of
10^{-5}a.u. Energies for the 4 ^1\Sigma_u^+ and 4-6 ^3\Sigma_u^+ were improved
and accurate data for the 6 ^3\Sigma_g^+, 5 ^1\Sigma_u^+, and 6 ^1\Sigma_u^+
state are, to the best of the authors knowledge, presented for the first time.
Energy data for the seventh up to the nineth electronic state within each
subspace were obtained with an estimated error of the order of magnitude of
10^{-4}a.u. The 7 ^1\Sigma_g^+ and the 6 ^1\Sigma_u^+ state were found to
exhibit a very broad deep outer well at large internuclear distances.


title: Resonant magnetic field control of elastic scattering of cold 85Rb

abstract:
  A magnetic field dependent Feshbach resonance has been observed in the
elastic scattering collision rate between atoms in the F = 2, M = -2 state of
85 Rb. Changing the magnetic field by several Gauss caused the collision rate
to vary by a factor of 10,000, and the sign of the scattering length could be
reserved. The resonance peak is at 155.2(4) G and its width is 11.6(5) G. From
these results we extract much improved values for the three quantities that
characterize the interaction porential: the van der Waals coefficient C6, the
singlet scattering length, and the triplet scattering length.


title:
Novel Gas-Doping Technique for Local Spectroscopic Measurements in
  Pulsed-Power Systems

abstract:
  A novel method for doping plasmas in pulsed-power experiments with gaseous
elements has been developed. A fast gas valve, a nozzle, and a skimmer are used
to generate an ultrasonic gas beam that is injected into a planar-geometry
microsecond plasma-opening-switch (POS). An array of ionization probes with
relatively high spatial and temporal resolutions was developed for diagnosing
the absolute injected-gas density and its spatial profile. The properties of
the gas column were also studied using spectroscopy of line emission that
results from the interaction of the doped gas with the POS prefilled plasma.
The doped column is found to have a width of ~1 cm and a density of
(0.8-1.7)*10^14 cm-3. Observations of characteristic emission lines from the
doped atoms and their ions allow for various spectroscopic measurements, such
as the magnetic field from Zeeman splitting and the ion velocity distributions
from Doppler shifts, that are local in three dimensions. It is shown that this
gas doping technique can also be used to study proton-dominated plasmas that
cannot be studied with simple emission spectroscopy due to the lack of light
emitting ions. The variety of gases used with this method, together with the
small valve dimensions and its fast opening, make it potentially useful for
broad diagnostics of various short-duration plasma experiments.


title: Mesoscopic motion of atomic ions in magnetic fields

abstract:
  We introduce a semiclassical model for moving highly excited atomic ions in a
magnetic field which allows us to describe the mixing of the Landau orbitals of
the center of mass in terms of the electronic excitation and magnetic field.
The extent of quantum energy flow in the ion is investigated and a crossover
from localization to delocalization with increasing center of mass energy is
detected. It turns out that our model of the moving ion in a magnetic field is
closely connected to models for transport in disordered finite-size wires.


title:
Calculations of the Relativistic Effects in Many-Electron Atoms and
  Space-Time Variation of Fundamental Constants

abstract:
  Theories unifying gravity and other interactions suggest the possibility of
spatial and temporal variation of physical ``constants'' in the Universe.
Detection of high-redshift absorption systems intersecting the sight lines
towards distant quasars provide a powerful tool for measuring these variations.
We have previously demonstrated that high sensitivity to the variation of the
fine structure constant $\alpha$ can be obtained by comparing spectra of heavy
and light atoms (or molecules). Here we describe new calculations for a range
of atoms and ions, most of which are commonly detected in quasar spectra: Fe
II, Mg II, Mg I, C II, C IV, N~V, O I, Al III, Si II, Si IV, Ca I, Ca II, Cr
II, Mn II, Zn II, Ge II (see the results in Table 3). The combination of Fe II
and Mg II, for which accurate laboratory frequencies exist, have already been
used to constrain $\alpha$ variations. To use other atoms and ions, accurate
laboratory values of frequencies of the strong E1-transitions from the ground
states are required. We wish to draw the attention of atomic experimentalists
to this important problem.
  We also discuss a mechanism which can lead to a greatly enhanced sensitivity
for placing constraints on variation on fundamental constants. Calculations
have been performed for Hg II, Yb II, Ca I and Sr II where there are optical
transitions with the very small natural widths, and for hyperfine transition in
Cs I and Hg II.


title:
Quantum Noise Reduction and Generalized Two-Mode Squeezing in a Cavity
  Raman Laser

abstract:
  We study a generalized notion of two-mode squeezing for the Stokes and
anti-Stokes fields in a model of a cavity Raman laser, which leads to a
significant reduction in decoherence or quantum noise. The model comprises a
loss-less cavity with classical pump, unsaturated medium and arbitrary
homogeneous broadening and dispersion. Allowing for arbitrary linear
combinations of the two modes in the definition of quadrature variables, we
find that there always exists a combination of the two output modes which
exhibits quadrature squeezing with noise reduction below the vacuum level. The
number of noise photons for this combination mode is proportional to the square
root of the number of Stokes noise photons.


title:
Dispersion-induced generation of higher order transversal modes in
  singly-resonant optical parametric oscillators

abstract:
  We study the effects of higher order transversal modes in a model of a
singly-resonant OPO, using both numerical solutions and mode expansions
including up to two radial modes. The numerical and two-mode solutions predict
lower threshold and higher conversion than the single-mode solution at negative
dispersion. Relative power in the zero order radial mode ranges from about 88%
at positive and small negative dispersion to 48% at larger negative dispersion,
with most of the higher mode content in the first mode, and less than 2% in
higher modes.


title:
On Possibility of Coulomb Interaction between Masses and Electrical
  Charges

abstract:
  From non-linear modification of Maxwell-Einstein theory, considered in
(physics/9801031), follows modified Coulomb law for interaction between charged
objects. Namely, if $(m, e)$ and $(m', e')$ are masses and charges of two
objects, then the potential energy of interaction, $V(r) = [ee' - kmm' -
\sqrt{k}(em' + e'm)]/r $, where $k$ is Newtonian constant. It follows, that the
Earth should possess negative electric charge, $Q_E = - \sqrt{k} M_E$. Obtained
result explains, why do primary cosmic rays consist mainly of positive charges.


title:
Quantum chaos, statistical equilibrium and resonant radiative capture of
  electrons by multicharged ions: Au 24+

abstract:
  We show that the spectrum and eigenstates of open-shell multicharged atomic
ions near the ionization threshold are chaotic, as a result of extremely high
level densities of multiply excited electron states (1000 levels per eV in Au
24+) and a strong configuration mixing. This complexity enables one to use
statistical methods to analyze the system. The orbital occupation numbers obey
the Fermi-Dirac distribution, and temperature can be introduced. We show that
radiative capture of electrons through the multielectron resonant states is
strongly enhanced compared to the direct radiative recombination.


title:
Diffractive effects in singly-resonant continuous-wave parametric
  oscillators

abstract:
  This paper presents a detailed numerical study of the effect of focusing on
the conversion efficiency of low-loss singly-resonant parametric oscillators
with collinear focusing of pump and signal. Results are given for the maximal
pump depletion and for pump power levels required for various amounts of
depletion, as functions of pump and signal confocal parameters, for kI/kP=0.33
and 0.50. It is found that the ratio of pump depletion to maximal depletion as
a function of the ratio of pump power to threshold power agrees with the
plane-wave prediction to within 5%, for a wide range of focusing conditions.
The observed trends are explained as resulting from intensity and phase
dependent mechanisms.


title:
On the mechanism of formation of the Efimov states in the helium ^4He
  trimer

abstract:
  A mechanism of disappearance and formation of the Efimov levels of the helium
^4He trimer is studied when the force of the interatomic interaction is
changed. It is shown that these levels arise from virtual levels which are in
turn formed from (quasi)resonances settled on the real axis. The resonances
including virtual levels are calculated by the method based on the solution of
the boundary value problem, at complex energies, for the Faddeev differential
equations describing the scattering processes (2+1\to 2+1; 1+1+1). All the
calculations are performed with the known interatomic Aziz He-He potential
HFD-B. A very strong repulsive component of this potential at short distances
between helium atoms is approximated by a hard core. A special attention is
paid to the substantiation of the method used for computing resonances and to
the investigation of its applicability range.


title: Nonlinear Electrodynamics: One-Electron Atom

abstract:
  From non-linear theory of electromagnetism, suggested in (physics/9801031),
follows that non-relativistic equation for scalar potential of electron in the
field of nuclei is equivalent to respective Schr\"odinger equation. For mass
and charge densities of electron the expressions from (physics/9811048) are
taken. The energy quantizing demands quantizing of parameters $\nu$ and $q$, as
well as $m$ and $e$.


title: Density Operators for Fermions

abstract:
  The mathematical methods that have been used to analyze the statistical
properties of boson fields, and in particular the coherence of photons in
quantum optics, have their counterparts for Fermi fields. The coherent states,
the displacement operators, the P-representation, and the other operator
expansions all possess surprisingly close fermionic analogues. These methods
for describing the statistical properties of fermions are based upon a
practical calculus of anti-commuting variables. They are used to calculate
correlation functions and counting distributions for general systems of
fermions.


title:
The lid method for exhaustive exploration of metastable states of
  complex systems

abstract:
  The `lid' algorithm performs an exhaustive exploration of neighborhoods of
local energy minima of energy landscapes. This paper describes an
implementation of the algorithm, including issues of parallel performance and
scalability. To illustrate the versatility of the approach and to stress the
common features present in landscapes of quite different systems, we present
selected results for 1) a spin glass, 2) a ferromagnet, 3) a covalent network
model for glassy systems, and 4) a polymer. The exponential nature of the local
density of states found in these systems and its relation to the ordering
transition is briefly commented upon.


title: Quantum Mechanics: I

abstract:
  This is the first Internet course on elementary quantum mechanics written in
Spanish ("castellano") for the benefit of Spanish speaking students. I thank my
eight Mexican students at the Institute of Physics, University of Guanajuato,
Leon, (IFUG), for the collaboration that made this possible. The topics
included refer to the postulates of quantum mechanics, one-dimensional barriers
and wells, angular momentum, WKB method, harmonic oscillator, hydrogen atom,
quantum scattering, and partial waves


title: Solitary Waves on a Coasting High-Energy Stored Beam

abstract:
  In this work we derive evolution equations for the nonlinear behavior of a
coasting beam under the influence of a resonator impedance. Using a
renormalization group approach we find a set of coupled nonlinear equations for
the beam density and the resonator voltage. Under certain conditions, these may
be analytically solved yielding solitary wave behavior, even in the presence of
significant dissipation in the resonator. We find long-lived perturbations,
i.e. droplets, which separate from the beam and decelerate towards a
quasi-equilibrium state, in good agreement with simulation results.

categories: physics.acc-ph nlin.PS patt-sol physics.plasm-ph


title: The "fingers" of the physics

abstract:
  The passage of particles through matter is one of the principal ways to
investigate nature. In this article, we would like to outline the most
important stages in the development of the theory about the stopping power.


title: Short range gravitational fields: Rise and fall of the fifth force

abstract:
  During the 80's, some experiments and the repetitions of old ones, lead to
the hypothesis of a fifth force. Nevertheless, a more accurate research was not
able to confirm this hypothesis. This article wants to go over again the most
important steps of the event.


title:
Coherent Nonlinear Phenomena in High Energy Synchrotrons: Observations
  and Theoretical Models

abstract:
  Nonlinear waves have been observed in synchrotrons for years but have
received little attention in the literature. While pathological, these
phenomena are worth studying on at least two accounts. First, the formation of
solitary waves may lead to droplet formation that causes significant beam halo
to develop. Secondly, a variety of nonlinear processes are likely involved in
the normal saturation of unstable oscillations, leading to the possibility that
low-level, but potentially broadband fluctuation spectra may develop. Both
features carry indirectly the signature of the machine impedance. In this work
we review a number of observations of nonlinear longitudinal waves made in
Fermilab accelerators, and make a first attempt to develop appropriate
theoretical models to explain these observations.


title:
Structures and Stabilities of Doubly-charged (MgO)nMg2+ (n=1-29) Cluster
  Ions

abstract:
  Ab initio perturbed ion plus polarization calculations are reported for
doubly-charged nonstoichiometric (MgO)nMg2+ (n=1-29) cluster ions. We consider
a large number of isomers with full relaxations of the geometries, and add the
correlation correction to the Hartree-Fock energies for all cluster sizes. The
polarization contribution is included at a semiempirical level also for all
cluster sizes. Comparison is made with theoretical results for neutral (MgO)n
clusters and singly-charged alkali-halide cluster ions. Our method is also
compared to phenomenological pair potential models in order to asses their
reliability for calculations on small ionic systems. The large
coordination-dependent polarizabilities of oxide anions favor the formation of
surface sites, and thus bulklike structures begin to dominate only after n=24.
The relative stabilities of the cluster ions against evaporation of a MgO
molecule show variations that are in excellent agreement with the experimental
abundance spectra.


title: Generalised-Lorentzian Thermodynamics

abstract:
  We extend the recently developed non-gaussian thermodynamic formalism
\cite{tre98} of a (presumably strongly turbulent) non-Markovian medium to its
most general form that allows for the formulation of a consistent thermodynamic
theory. All thermodynamic functions, including the definition of the
temperature, are shown to be meaningful. The thermodynamic potential from which
all relevant physical information in equilibrium can be extracted, is defined
consistently. The most important findings are the following two: (1) The
temperature is defined exactly in the same way as in classical statistical
mechanics as the derivative of the energy with respect to the entropy at
constant volume. (2) Observables are defined in the same way as in Boltzmannian
statistics as the linear averages of the new equilibrium distribution function.
This lets us conclude that the new state is a real thermodynamic equilibrium in
systems capable of strong turbulence with the new distribution function
replacing the Boltzmann distribution in such systems. We discuss the ideal gas,
find the equation of state, and derive the specific heat and adiabatic exponent
for such a gas. We also derive the new Gibbsian distribution of states. Finally
we discuss the physical reasons for the development of such states and the
observable properties of the new distribution function.


title: The finite one-dimensional wire problem

abstract:
  We discuss an elementary problem in electrostatics: What does the charge
distribution look like for a free charge on a strictly one-dimensional wire of
finite length? To the best of our knowledge this question has so far not been
discussed anywhere. One notices that a solution of this problem is not as
simple as it might appear at first sight.


title: Collective Absorption Dynamics and Enhancement in Deformed Targets

abstract:
  The interaction of intense fs laser pulses with thin foils that have an
imposed deformation is compared with thick targets that develop bow shocks.
Both target types yield good absorption. Up to 80% absorption is obtained for a
$0.2\mu m$ thick, 15 times over-dense foil at $4 \cdot 10^{18} W/cm^2$. A value
of 50% is obtained for a $4 \mu m$ thick, 2 times over-dense thick target at
$10^{18} W/cm^2$. For comparable extension and curvature of the laser-plasma
interfaces absorption levels in both targets become similar. In both absorption
scales weakly with intensity and density. Energy transport in thin foils and
thick targets, however, is different.


title:
Some Remarks on the Question of Charge Densities in
  Stationary-Current-Carrying Conductors

abstract:
  Recently, some discussions arose as to the definition of charge and the value
of the density of charge in stationary-current-carrying conductors. We stress
that the problem of charge definition comes from a misunderstanding of the
usual definition. We provide some theoretical elements which suggest that
positive and negative charge densities are equal in the frame of the positive
ions.


title: Hydrogen atom in crossed external fields reexemined by the moment method

abstract:
  Recurrence relations of perturbation theory for hydrogen ground state are
obtained. With their aid polarizabilities in constant perpendicular electric
and magnetic fields are computed up to 80th order. The high orders asymptotic
is compared with its quasiclassical estimate. For the case of arbitrary mutual
orientation of external fields a general sixth order formula is given.


title: Stochastic Stokes' drift

abstract:
  Classical Stokes' drift is the small time-averaged drift velocity of
suspended non-diffusing particles in a fluid due to the presence of a wave. We
consider the effect of adding diffusion to the motion of the particles, and
show in particular that a non-zero time-averaged drift velocity exists in
general even when the classical Stokes' drift is zero. Our results are obtained
from a general procedure for calculating ensemble-averaged Lagrangian mean
velocities for motion that is close to Brownian, and are verified by numerical
simulations in the case of sinusoidal forcing.


title: A Reconsideration of Matter Waves

abstract:
  Matter waves were discovered in the early 20th century from their wavelength,
predicted by DeBroglie, Planck's constant divided by the particle's momentum,
that is, lmw = h/mv. But, the failure to obtain a reasonable theory for the
matter wave frequency resulted somewhat in loss of further interest.
  It was expected that the frequency of the matter wave should correspond to
the particle kinetic energy, that is, fmw = 1/2mv^2/h but the resulting
velocity of the matter of the particle, v = fmw x lmw, is that the matter wave
moves at one half the speed of the particle, obviously absurd as the particle
and its wave must move together.
  If relativistic mass is used (as it should in any case) the problem remains,
the same mass appearing in numerator and denominator and canceling. It is no
help to hypothesize that the total energy, not just the kinetic energy, yields
the matter wave. That attributes a matter wave to a particle at rest. It also
gives the resulting velocity as c^2/v, the wave racing ahead of its particle.
  A reinterpretation of Einstein's derivation of relativistic kinetic energy
(which produced his famous E = mc^2) leads to a valid matter wave frequency and
a new understanding of particle kinetics and of the atom's stable orbits.


title:
DNA - Nanoelectronics: Realization of a Single Electron Tunneling
  Transistor and a Quantum Bit Element

abstract:
  Based on the understanding that chemical bonds can act as tunnel junctions in
the Coulomb blockade regime, and on the technical ability to coat a DNA strand
with metal, we suggest that DNA can be used to built logical devices. We
discuss two explicit examples: a Single Electron Tunneling Transistor (SET) and
a Quantum Bit Element. These devices would be literally in the nano-meter scale
and would be able to operate at room temperature. In addition they would be
identical to each other, highly stable and would have a self assembly property.


title: A New Look at the Neutron and the Lamb Shift

abstract:
  The rest mass of the neutron is exactly equal to the rest mass of a proton
plus that of an electron plus the mass equivalent of the kinetic energy of
those two particles after they have electrostatically accelerated from very far
apart toward each other to a separation distance of one proton diameter. That
fact is either a remarkable coincidence or evidence that the neutron is a
combination of a proton and an electron. The calculation of this sheds new
light on the nature and significance of the Lamb Shift.


title:
Asymptotic channels and gauge transformations of the time-dependent
  Dirac equation for extremely relativistic heavy-ion collisions

abstract:
  We discuss the two-center, time-dependent Dirac equation describing the
dynamics of an electron during a peripheral, relativistic heavy-ion collision
at extreme energies. We derive a factored form, which is exact in the
high-energy limit, for the asymptotic channel solutions of the Dirac equation,
and elucidate their close connection with gauge transformations which transform
the dynamics into a representation in which the interaction between the
electron and a distant ion is of short range. We describe the implications of
this relationship for solving the time-dependent Dirac equation for extremely
relativistic collisions.


title: Analytical Treatment of Stabilization

abstract:
  We present a summarizing account of a series of investigations whose central
topic is to address the question whether atomic stabilization exists in an
analytical way. We provide new aspects on several issues of the matter in the
theoretical context when the dynamics is described by the Stark Hamiltonian.
The main outcome of these studies is that the governing parameters for this
phenomenon are the total classical momentum transfer and the total classical
displacement. Whenever these two quantities vanish, asymptotically weak
stabilization does exist. For all other situations we did not find any evidence
for stabilization. We found no evidence that strong stabilization might occur.
Our results agree qualitatively with the existing experimental findings.


title:
Modelling by maps of two-frequency microwave ionization of hydrogen
  atoms

abstract:
  Mapping equations of motion of the highly exited classical atom in a
monochromatic field are generalized for the two-frequency microwave field.
Analysis of the obtained equations indicates to the weak sensitivity of the
position of the recently observed ionization peak near the main resonance to
the frequency and amplitude of the additional microwave field. In the high
frequency region, however, the sensitivity of the enhanced ionization peaks on
the additional field frequency is predicted.


title: A Problem of Relative, Constrained Motion

abstract:
  We develop a new method to determine the acceleration of a block sliding down
along the face of a moving wedge. We have been able to link the solution of
this problem to that of the inclined plane problem of elementary physics, thus
providing a simpler solution to it.


title: Logic, Truth and Probability

abstract:
  The propositional logic is generalized on the real numbers field. The logical
analog of the Bernoulli independent tests scheme is constructed. The variant of
the nonstandard analysis is adopted for the definition of the logical function,
which has all properties of the classical probability function. The logical
analog of the Large Number Law is deduced from properties of this function.


title: How and Why Inertial Mass and Gravitational Mass are Equal and Identical

abstract:
  Present physics theory deems that the inertial mass characteristic of matter
is the result of the interaction of that matter with a newly defined additional
field called the Higgs Field after its principle researcher. Stated briefly,
the Higgs field mechanism endows "gauge bosons" in a "gauge theory" with mass,
through absorption of "Nambu-Goldstone bosons" arising in spontaneous "symmetry
breaking".
  Present physics theory deems that the gravitational mass characteristic of
matter is the result of that matter "curving" or "warping" space and time
according to the matter's presence through a mechanism not yet discovered nor
defined.
  Present physics recognizes that inertial mass and gravitational mass are
equal as an empirical fact based on highly precise experiments. But, for
example, the Earth in its orbit around the Sun experiences attraction toward
the Sun involving its gravitational mass, mg, and simultaneously experiences
that attraction balanced by Earth's orbital centripetal force involving its
inertial mass, mi.
  G M mg / r^2 = mi v^2 / r
  That the matter of planet Earth is being endowed "gauge theory bosons with
mass through absorption of Nambu-Goldstone bosons symmetry breaking in a Higgs
Field" while simultaneously "warping or curving its region of space" is beyond
the unreasonable and is simply inconceivable.
  The resolution of this issue and phenomenon is presented in the following.


title: The Einstein - Lorentz Dispute Revisited

abstract:
  Lorentz [of the Lorentz transforms and Lorentz contractions fame] contended
against Einstein that there had to be a medium in which electro-magnetic waves
exist and propagate, and that that would of necessity be an absolute frame of
reference for the universe. Einstein won that dispute contending that
electro-magnetic waves needed no medium and that there was no absolute frame of
reference. But, that victory was in a conflict of the Lorentz opinion opposed
to the Einstein opinion combined with the substantial other successes and
reputation or Einstein. It was not a victory of solid reasoning nor
demonstrated factual evidence. Now solid reasoning and new data not available
to Einstein and Lorentz show that Lorentz was correct and that Einstein's
Theory of Relativity should correctly be termed Einstein's Principle of
Invariance. It is shown that Einstein's comprehensive relativity and denial of
an absolute frame of reference for the universe are incorrect and that the
universe has an absolute universal prime frame of reference. The significance
of this correction in its relation to the interaction of science and society is
then presented.


title: Polytopes and Nuclear Structure

abstract:
  While the parameters of atomic nuclei, Z and A, indicate a general structural
pattern for the nuclei, their exact masses in their fine differences seem not
to exhibit the orderly kind of logical system that systematic and orderly
nature must exhibit. Appropriate analysis discloses an orderly structure among
all the nuclear types and isotopes. A component of that analysis and logical
order is the family of geometric forms called polytopes, in particular the
regular polyhedrons.


title: Non-Markovian effects in the solar neutrino problem

abstract:
  The solar core, because of its density and temperature, is not a
weakly-interacting or a high-temperature plasma. Collective effects have time
scales comparable to the average time between collisions, and the microfield
distribution influences the particle dynamics. In this conditions ion and
electron diffusion is a non-Markovian process, memory effects are present and
the equilibrium statistical distribution function differs from the Maxwellian
one. We show that, even if the deviations from the standard velocity
distribution that are compatible with our present knowledge of the solar
interior are small, they are sufficient to sensibly modify the sub-barrier
nuclear reaction rates. The consequent changes of the neutrino fluxes are
comparable to the flux deficits that constitute the solar neutrino problem.


title:
Comparison of Recoil-Induced Resonances (RIR) and Collective Atomic
  Recoil Laser (CARL)

abstract:
  The theories of recoil-induced resonances (RIR) [J. Guo, P. R. Berman, B.
Dubetsky and G. Grynberg, Phys. Rev. A {\bf 46}, 1426 (1992)] and the
collective atomic recoil laser (CARL) [ R. Bonifacio and L. De Salvo, Nucl.
Instrum. Methods A {\bf 341}, 360 (1994)] are compared. Both theories can be
used to derive expressions for the gain experienced by a probe field
interacting with an ensemble of two-level atoms that are simultaneously driven
by a pump field. It is shown that the RIR and CARL formalisms are equivalent.
Differences between the RIR and CARL arise because the theories are typically
applied for different ranges of the parameters appearing in the theory. The RIR
limit considered in this paper is $qP_{0}/M\omega_{q}\gg 1$, while the CARL
limit is $qP_{0}/M\omega_{q}\lesssim 1$, where $% q $ is the magnitude of the
difference of the wave vectors of the pump and probe fields, $P_{0}$ is the
width of the atomic momentum distribution and $% \omega_{q}$ is a recoil
frequency. The probe gain for a probe-pump detuning equal to zero is analyzed
in some detail, in order to understand how the gain arises in a system which,
at first glance, might appear to have vanishing gain. Moreover, it is shown
that the calculations, carried out in perturbation theory have a range of
applicability beyond the recoil problem. Experimental possibilities for
observing CARL are discussed.


title: Matter Waves and Orbital Quantum Numbers

abstract:
  The atom's orbital electron structure in terms of quantum numbers (principal,
azimuthal, magnetic and spin) results in space for a maximum of: 2 electrons in
the n=1 orbit, 8 electrons in the n=2 orbit, 18 electrons in the n=3 orbit, and
so on. Those dispositions are correct, but that is not because of quantum
numbers nor angular momentum nor a "Pauli exclusion principle".
  Matter waves were discovered in the early 20th century from their wavelength,
which was predicted by DeBroglie to be, Planck's constant divided by the
particle's momentum. But, the failure to obtain a reasonable theory for the
matter wave frequency resulted in loss of interest. That problem is resolved in
"A Reconsideration of Matter Waves" in which a reinterpretation of Einstein's
derivation of relativistic kinetic energy [which produced his famous E = mc^2]
leads to a valid matter wave frequency and a new understanding of particle
kinetics and the atom's stable orbits.
  It is analytically shown that the orbital electron arrangement is enforced by
the necessity of accommodating the space that each orbiting electron's matter
wave occupies.


title: Information content in Gaussian noise: optimal compression rates

abstract:
  We approach the theoretical problem of compressing a signal dominated by
Gaussian noise. We present expressions for the compression ratio which can be
reached, under the light of Shannon's noiseless coding theorem, for a linearly
quantized stochastic Gaussian signal (noise). The compression ratio decreases
logarithmically with the amplitude of the frequency spectrum $P(f)$ of the
noise. Entropy values and compression rates are shown to depend on the shape of
this power spectrum, given different normalizations. The cases of white noise
(w.n.), $f^{n_p}$ power-law noise ---including $1/f$ noise---, (w.n.$+1/f$)
noise, and piecewise (w.n.+$1/f |$ w.n.$+1/f^2$) noise are discussed, while
quantitative behaviours and useful approximations are provided.


title: An analysis of dynamical suppression of spontaneous emission

abstract:
  It has been shown recently [see, for example, S.-Y. Zhu and M. O. Scully,
Phys. Rev. Lett. {\bf 76}, 388 (1996)] that a dynamical suppression of
spontaneous emission can occur in a three-level system when an external field
drives transitions between a metastable state and {\em two} decaying states.
What is unusual in the decay scheme is that the decaying states are coupled
directly by the vacuum radiation field. It is shown that decay dynamics
required for total suppression of spontaneous emission necessarily implies that
the level scheme is isomorphic to a three-level lambda system, in which the
lower two levels are {\em both} metastable, and each is coupled to the decaying
state. As such, the total suppression of spontaneous emission can be explained
in terms of conventional dark states and coherent population trapping.


title: The rovibrational kinetic energy for complexes of rigid molecules

abstract:
  The rovibrational kinetic energy for an arbitrary number of rigid molecules
is computed. The result has the same general form as the kinetic energy in the
molecular rovibrational Hamiltonian, although certain quantities are augmented
to account for the rotational energy of the monomers. No specific choices of
internal coordinates or body frame are made in order to accommodate the large
variety of such conventions. However, special attention is paid to how key
quantities transform when these conventions are changed. An example system is
explicitly analysed as an illustration of the formalism.


title:
A New Approach To Relativistic Gaussian Basis Functions: Theory And
  Applications

abstract:
  We present a new hybrid method to solve the relativistic Hartree-Fock-Roothan
equations where the one- and two-electron radial integrals are evaluated
numerically by defining the basis functions on a grid. This procedure reduces
the computational costs in the evaluation of two-electron radial integrals. The
orbitals generated by this method are employed to compute the ionization
potentials, excitation energies and oscillator strengths of alkali-metal atoms
and elements of group IIIA through second order many-body perturbation theor
and other correlated theories.


title: Soliton Model of Hydrogen Atom: Resonance Effects

abstract:
  Some first principles that, we believe, could serve as foundation for quantum
theory of extended particles are formulated. It is also shown that in the
point-like particles limit the non-relativistic quantum mechanics can be
restored. As an illustration the soliton model of hydrogen atom is considered.


title: Bounds on the Mobility of Electrons in Weakly Ionized Plasmas

abstract:
  We obtain exact upper and lower bounds on the steady state drift velocity,
and kinetic energy of electrons, driven by an external field in a weakly
ionized plasma (swarm approximation). The scattering is assumed to be elastic
with simplified velocity dependence of the collision cross sections. When the
field is large the bounds are close to each other and to the results obtained
from the conventional approximation of the Boltzmann equation in which one
keeps only the first two terms of a Legendre expansion. The bounds prove
rigorously that it is possible to increase the electron mobility by the
addition of suitably chosen scatterers to the system as predicted by the
Druyvesteyn approximation and found in experiments.


title: Chaotic dynamics of cold atoms in far-off-resonant donut beam

abstract:
  We describe the classical two dimensinal nonlinear dynamics of cold atoms in
far-off-resonant donut beams. We show that there chaotic dynamics exists for
charge greater than unity, when the intensity of the beam is periodically
modulated. The two dimensional distributions of atoms in $(x,y)$ plane for
charge two are simulated. We show that the atoms will acumulate on several ring
regions when the system enters to regime of global chaos.


title: An Explicit Solution for Nonlinear Plasma Waves of Arbitrary Amplitude

abstract:
  Based on the known implicit solution for nonlinear plasma waves, an explicit
solution was obtained in the form of decomposition into harmonics. The solution
obtained exhibits a mechanism for steepening of nonlinear plasma wave as a
result of increasing contribution of harmonics and may be used in theoretical
studies of processes involving nonlinear plasma waves.


title: Energy Levels of Multielectron Atoms using the Sea-boson Method

abstract:
  In this article, we study an antithesis of the homogeneous Fermi system
(jellium model) namely a single multielectron atom using the sea-boson
approach. This system in addition to having a small number of electrons(finite
system) is also extremely inhomogeneous. This means that the plane-wave basis
is ill-suited to study this system, instead we use a basis consisting of the
eigenfunctions of an electron interacting with the nucleus situated at the
origin (ideal atom).
  We compute the energy levels of this system and polarizabilities and compare
with the results of other approaches such as Hartree-Fock and pseudopotentials
for the former and aysmptotic wavefunctions for the latter and with
experiments.


title:
Coulomb and spin-orbit interaction matrix elements in d^2d'
  configuration

abstract:
  The $d^2d'$ configuration is analysed in group-theoretical terms. Starting
from the table given by Condon and Odabasi (1980) for the configuration
$d^2d'$, we determine a set of convenient group-theoretical basis states, and
rewrite the Coulomb matrix elements in terms of this new basis. Linear
combinations from the different parts of the Coulomb operators are formed such
that they have simple group transformation properties in our scheme. The
sequence of groups that we use is $U(20) \supset SO_T(3) \times U(10) \supset
SO_T(3) \times SO_S(3) \times U(5) \supset SO_T(3) \times SO_S(3) \times SO(5)
\supset SO_T(3) \times SO_S(3) \times SO_L(3)$, where $T$ denotes the {\em
isospin} of \v Simonis et al (1984), in which electrons with the same angular
momentum $l$ but different principle quantum numbers $n$ are accommodated by
introducing the eigenvalue $M_T$ of $T_0$. Using the Wigner-Eckart theorem and
selection rules on the higher symmetry groups, the tables of the Coulomb and
spin-orbit matrix elements for the reconstituted operators (with simple group
transformation properties) are much simplified in terms of these basis states.


title:
Optimal conditions for light pulses coherence transformation in thin
  nonlinear media

abstract:
  Via solution of appropriate variational problem it is shown that light beams
with Gaussian spatial profile and sufficiently short duration provide maximal
destruction of global coherence under nonlinear self-modulation.


title: On the relativistic L-S coupling

abstract:
  The fact that the Dirac equation is linear in the space and time derivatives
leads to the coupling of spin and orbital angular momenta that is of a pure
relativistic nature. We illustrate this fact by computing the solutions of the
Dirac equation in an infinite spherical well, which allows to go from the
relativistic to the non-relativistic limit by just varying the radius of the
well.


title: Cold Collision Frequency Shift of the 1S-2S Transition in Hydrogen

abstract:
  We have observed the cold collision frequency shift of the 1S-2S transition
in trapped spin-polarized atomic hydrogen. We find $\Delta \nu_{1S-2S} =
-3.8(8)\times 10^{-10} n Hz cm^3$, where $n$ is the sample density. From this
we derive the 1S-2S s-wave triplet scattering length, $a_{1S-2S}=-1.4(3)$ nm,
which is in fair agreement with a recent calculation. The shift provides a
valuable probe of the distribution of densities in a trapped sample.


title: Bose-Einstein Condensation of Atomic Hydrogen

abstract:
  We report observation of Bose-Einstein condensation of a trapped, dilute gas
of atomic hydrogen. The condensate and normal gas are studied by two-photon
spectroscopy of the 1S-2S transition. Interactions among the atoms produce a
shift of the resonance frequency proportional to density. The condensate is
clearly distinguished by its large frequency shift. The peak condensate density
is 4.8 +/- 1.1 \times 10^{15} cm^{-3}, corresponding to a condensate population
of 10^9 atoms. The BEC transition occurs at about T=50 uK and n=1.8 \times
10^{14} cm^{-3}.


title: Formation of Patterns and Coherent Structures in Charged Particle Beams

abstract:
  In the present paper we study the long wavelength and slow time scale
behavior of a coasting beam in a resonator adopting a broad-band impedance
model. Based on the renormalization group approach we derive a set of coupled
evolution equations for the beam envelope distribution function and the
resonator voltage amplitude. The equation for the resonator voltage amplitude
is further transformed into a generalized Ginzburg-Landau equation.


title:
Orbital-Free Molecular Dynamics Simulations of Melting in Na8 and Na20:
  Melting in Steps

abstract:
  The melting-like transitions of Na8 and Na20 are investigated by ab initio
constant energy molecular dynamics simulations, using a variant of the
Car-Parrinello method which employs an explicit electronic kinetic energy
functional of the density, thus avoiding the use of one-particle orbitals.
Several melting indicators are evaluated in order to determine the nature of
the various transitions, and compared with other simulations. Both Na8 and Na20
melt over a wide temperature range. For Na8, a transition is observed to begin
at approx. 110 K, between a rigid phase and a phase involving isomerizations
between the different permutational isomers of the ground state structure. The
``liquid'' phase is completely established at approx. 220 K. For Na20, two
transitions are observed: the first, at approx. 110 K, is associated with
isomerization transitions between those permutational isomers of the ground
state structure which are obtained by interchanging the positions of the
surface-like atoms; the second, at approx. 160 K, involves a structural
transition from the ground state isomer to a new set of isomers with the
surface molten. The cluster is completely ``liquid'' at approx. 220 K.


title: Muonium

abstract:
  The energy levels of the muonium ($\mu^+ e^-$) atom, which consists of two
''point-like'' leptonic particles, can be calculated to very high accuracy in
the framework of bound state Quantum Electrodynamics (QED), since there are no
complications due to internal nuclear structure and size which is the case for
all atoms and ions of natural isotopes including atomic hydrogen. The ground
state hyperfine splitting and the 1s-2s energy interval can provide both tests
of QED theory and determinations of fundamental constants like the muon mass
$m_{\mu}$ and the fine structure constant $\alpha$. The excellent understanding
of the electromagnetic binding in the muonium atom allows in particular testing
fundamental physical laws like lepton number conservation in searches for
muonium to antimuonium conversion and probing the nature of the muon as a heavy
leptonic object. New measurements on the ground state hyperfine splitting and
the 1s-2s transition are discussed.


title: Ha spectroscopy for hot plasma parameters measurement

abstract:
  The new spectroscopic method for measurement of hot plasma parameters is
developed. The method based on Ha profile monitoring. The profile was
accurately calculated for a wide range of plasma parameters (n$_e \sim $
10$^{14} \div $ 10$^{17}$ cm$^{-3}$, T$_e \sim 1\div$500 eV) Use of the method
in the experiment gives the electron density and ion temperature dependence
from the time. Measurements was in a good agreement with diamagnetic loop
dates.
  Key words: H$_\alpha$ spectroscopy, line profile, density and high
temperature measurement.


title:
Nucleon Polarizability Contribution to the Hydrogen Lamb Shift and
  Hydrogen -- Deuterium Isotope Shift

abstract:
  The correction to the hydrogen Lamb shift due to the proton electric and
magnetic polarizabilities is expressed analytically through their static
values, which are known from experiment. The numerical value of the correction
to the hydrogen 1S state is $ - 71 \pm 11 \pm 7$ Hz. Correction to the H-D
1S-2S -- isotope shift due to the proton and neutron polarizabilities is
estimated as $ 53 \pm 9 \pm 11$ Hz.


title: A Solution to the Gating Paradox

abstract:
  We introduce a Markov model for the gating of membrane channels. The model
features a possible solution to the so-called gating current paradox, namely
that the bell-shaped curve that describes the voltage dependence of the
kinetics is broader than expected from, and shifted relative to, the sigmoidal
curve that describes the voltage dependence of the activation. The model also
predicts some temperature dependence of this shift, but presence of the latter
has not been tested experimentally so far.


title: A necessary and sufficient instability condition for inviscid shear flow

abstract:
  The linear stability of inviscid, incompressible, two-dimensional, plane
parallel, shear flow was considered over a century ago by Rayleigh, Kelvin, and
others. A principal result on the subject is Rayleigh's celebrated inflection
point theorem {R80}, which states that for an equilibrium flow to be unstable,
the equilibrium velocity profile must contain an inflection point. That is, if
the velocity profile is given by $U(y)$, where $y$ is the cross-stream
coordinate, then there must be a point, $y=y_I$, for which $U''(y_I)=0$. Much
later, in 1950, Fj{\o}rtoft {F50} generalized the theorem by showing that,
moreover, if there is one inflection point, then $U'''(y_I)/U'(y_I)<0$ is
required for instability (see {Bar} for further extensions). Both Rayleigh's
Theorem and Fj{\o}rtoft's subsequent generalization are necessary conditions
for instability, but they are not sufficient. That is, even though an
equilibrium profile may contain a vorticity minimum, it is not necessarily
unstable. The point of this paper is to derive, for a large class of
equilibrium velocity profiles, a condition that is necessary and sufficient for
instability.


title: Relativizing relativity

abstract:
  Special relativity theory is generalized to two or more ``maximal''
signalling speeds. This framework is discussed in three contexts: (i) as a
scenario for superluminal signalling and motion, (ii) as the possibility of two
or more ``light'' cones due to the a ``birefringent'' vaccum, and (iii) as a
further extension of conventionality beyond synchrony.


title: An accelerated charge is also absorbing power

abstract:
  An accelerated classical point charge radiates at the Larmor power rate
$2e^2a^2/3$, leading to the expectation of an associated radiation reaction
force. The famous Abraham-Lorentz-Dirac proposal is plagued with difficulties.
Here we note a simple, amazing, and apparently overlooked fact: an accelerated
charge is also always absorbing power at exactly the Larmor rate. Implications
for radiation reaction and the particle motion are considered. Our analysis
supports Kijowski's recent proposal.


title:
Optical vernier technique for in-situ measurement of the length of long
  Fabry-Perot cavities

abstract:
  We propose a method for in-situ measurement of the length of kilometer size
Fabry-Perot cavities in laser gravitational wave detectors. The method is based
on the vernier, which occurs naturally when the laser incident on the cavity
has a sideband. By changing the length of the cavity over several wavelengths
we obtain a set of carrier resonances alternating with sideband resonances.
  From the measurement of the separation between the carrier and a sideband
resonance we determine the length of the cavity. We apply the technique to the
measurement of the length of a Fabry-Perot cavity in the Caltech 40m
Interferometer and discuss the accuracy of the technique.


title:
Newtonian approach for the Kepler-Coulomb problem from the point of view
  of velocity space

abstract:
  The hodograph of the Kepler-Coulomb problem, that is, the path traced by its
velocity vector, is shown to be a circle and then it is used to investigate
other properties of the motion. We obtain the configuration space orbits of the
problem starting from initial conditions given using nothing more than the
methods of synthetic geometry so close to Newton's approach. The method works
with elliptic, parabolic and hyperbolic orbits; it can even be used to derive
Rutherford's relation from which the scattering cross section can be easily
evaluated. We think our discussion is both interesting and useful inasmuch as
it serves to relate the initial conditions with the corresponding trajectories
in a purely geometrical way uncovering in the process some seldom discussed
interesting connections.


title:
Analysis of The Anomalous Orbital-Energy Changes Observed in Spacecraft
  Flybys of Earth

abstract:
  In March 2008 anomalous behavior in spacecraft flybys of Earth was reported
in Physical Review Letters, Volume 100, Issue 9, March 7, 2008, in an article
entitled "Anomalous Orbital-Energy Changes Observed during Spacecraft Flybys of
Earth".
  The data indicate unaccounted for changes in spacecraft speed, both increases
and decreases, for six different spacecraft involved in Earth flybys from
December 8, 1990 to August 2, 2005. The article states that, "All ... potential
sources of systematic error .... [have been] modeled. None can account for the
observed anomalies.... Like the Pioneer anomaly ... the Earth flybys anomaly is
a real effect .... Its source is unknown."
  In the present article it is shown that the Earth flybys anomaly would be
caused by a very small acceleration [in addition to that of natural
gravitation], centrally directed and independent of distance, the same effect
as that which the Pioneer anomaly exhibits. How that effect operates to produce
the observed results is analyzed. A cause of the centrally directed
accelerations is presented.


title:
Systematics of the Genetic Code and Anticode: History, Supersymmetry,
  Degeneracy and Periodicity

abstract:
  Important aspects of the process of information storage and retrieval in DNA
and RNA, and its evolution, are the role of the anticodons and associated
$t$RNA's, and correlations between anticodons and amino acids; the degeneracy
of the genetic code, and the periodicity of many amino acid physico-chemical
properties. Such factors are analysed in the context of a $sl(6/1)$
supersymmetric model of the genetic code.


title: Observation of proximity resonances in a parallel-plate waveguide

abstract:
  We have observed proximity resonances in a two dimensional system consisting
of dielectric scatterers in a parallel plate waveguide. A numerical solution to
the scattering problem supports the analysis of the experimental data.


title: Quantum theory of magnetic quadrupole lenses for spin-1/2 particles

abstract:
  General guidelines for constructing a quantum theory of charged-particle beam
optics starting ab initio from the basic equations of quantum mechanics,
appropriate to the situation under study. In the context of spin-1/2 particles,
these guidelines are used starting with the Dirac equation. The spinor theory
just constructed is used to obtain the transfer maps for normal and skew
magnetic quadrupoles respectively. As expected the traditional transfer maps
get modified by the quantum contributions. The classical limit of the quantum
formalism presented, reproduces the well-known Lie algebraic formalism of
charged-particle beam optics.


title:
Quantile motion of electromagnetic waves in wave guides of varying cross
  section and dispersive media

abstract:
  We discuss applications of the quantile concept of trajectories and
velocities to the propagation of electromagnetic signals in wave guides of
varying cross section. Quantile motion is a general description of the
transport properties of measurable conserved quantities in quantum mechanics as
well as in classical electrodynamics. In the latter case we consider the
quantile motion of electromagnetic energy as the direct result of a physical
measurement. In this sense the quantile velocity corresponds to the
electromagnetic signal velocity also in the presence of barriers and
inhomogeneities in the medium of propagation. We show that this signal velocity
is always smaller than the speed of light in vacuum. Using numerical examples
we demonstrate how typical wave phenomena can be described in terms of the
quantile motion.


title:
Collision Integrals and the Generalized Kinetic Equation for Charged
  Particle Beams

abstract:
  In the present paper we study the role of particle interactions on the
evolution of a high energy beam. The interparticle forces taken into account
are due to space charge alone. We derive the collision integral for a charged
particle beam in the form of Balescu-Lenard and Landau and consider its further
simplifications. Finally, the transition to the generalized kinetic equation
has been accomplished by using the method of adiabatic elimination of fast
variables.


title:
Objections to the Unified Approach to the Computation of Classical
  Confidence Limits

abstract:
  Conventional classical confidence intervals in specific cases are unphysical.
A solution to this problem has recently been published by Feldman and Cousins.
We show that there are cases where the new approach is not applicable and that
it does not remove the basic deficiencies of classical confidence limits.


title: Oxygen in the Earth's core: a first principles study

abstract:
  First principles electronic structure calculations based on density
functional theory have been used to study the thermodynamic, structural and
transport properties of solid solutions and liquid alloys of iron and oxygen at
Earth's core conditions. Aims of the work are to determine the oxygen
concentration needed to account for the inferred density in the outer core, to
probe the stability of the liquid against phase separation, to interpret the
bonding in the liquid, and to find out whether the viscosity differs
significantly from that of pure liquid iron at the same conditions. It is shown
that the required concentration of oxygen is in the region 25-30 mol percent,
and evidence is presented for phase stability at these conditions. The Fe-O
bonding is partly ionic, but with a strong covalent component. The viscosity is
lower than that of pure liquid iron at Earth's core conditions. It is shown
that earlier first-principles calculations indicating very large enthalpies of
formation of solid solutions may need reinterpretation, since the assumed
crystal structures are not the most stable at the oxygen concentration of
interest.


title: On Observability of Signal over Background

abstract:
  Several statistics used by physicists to declare the signal observability
over the background are compared. It is shown that the frequentist method of
testing a precise hypothesis allows one to estimate the power value of criteria
with specified level of significance for the considered statistics by Monte
Carlo calculations. The application of this approach for the analysis of
discovery potential of experiments is discussed.


title:
Dynamics of Fabry-Perot resonators with suspended mirrors. I. Nonlinear
  coupled oscillators

abstract:
  The dynamics of Fabry-Perot cavity with suspended mirrors is described. The
suspended mirrors are nonlinear oscillators interacting with each other through
the laser circulating in the cavity. The degrees of freedom decouple in normal
coordinates, which are the position of the center of mass and the length of the
cavity. We introduce two parameters and study how the dynamics changes with
respect to these parameters. The first parameter specifies how strong the
radiation pressure is. It determines whether the cavity is multistable or not.
The second parameter is the control parameter, which determines location of the
cavity equilibrium states. The equilibrium state shows hysteresis if the
control parameter varies within a wide range. We analyze stability of the
equilibrium states and identify the instability region. The instability is
explained in terms of the effective potential: the stable states correspond to
local minima of the effective potential and unstable states correspond to local
maxima. The minima of the effective potential defines the resonant frequencies
for the oscillations of the cavity length. We find the frequencies, and analyze
how to tune them. Multistability of the cavity with a feedback control system
is analyzed in terms of the servo potential. The results obtained in this paper
are general and apply to all Fabry-Perot cavities with suspended mirrors.


title: An extended liouville equation for variable particle number systems

abstract:
  It is well-known that the Liouville equation of statistical mechanics is
restricted to systems where the total number of particles (N) is fixed. In this
paper, we show how the Liouville equation can be extended to systems where the
number of particles can vary, such as in open systems or in systems where
particles can be annihilated or created. A general conservation equation for an
arbitrary dynamical variable is derived from the extended Liouville equation
following Irving and Kirkwood's2 technique. From the general conservation
equation, the particle number conservation equation is obtained that includes
general terms for the annihilation or creation of particles. It is also shown
that the grand canonical ensemble distribution function is a particular
stationary solution of the extended Liouville equation, as required. In
general, the extended Liouville equation can be used to study nonequilibrium
systems where the total number of particles can vary.


title:
Modal Expansions and Orthogonal Complements in the Theory of Complex
  Media Waveguide Excitation by External Sources for Isotropic, Anisotropic,
  and Bianisotropic Media

abstract:
  A unified electrodynamic approach to the guided wave excitation by external
sources in the waveguiding structures with bianisotropic media is developed.
Effect of electric, magnetic, and magneto- electric losses in such media
manifests itself in the special form of eigenmode orthogonality referred to as
the quasi-orthogonality relation. It reflects the existence of the cross-power
flow and for any pair of modes which are rigidly linked to each other by this
relation. The quasi-orthogonality relation remains true in the limiting case of
lossless waveguides yielding the customary relations of orthogonality and
normalization for propagating (active) modes and also their generalization for
nonpropagating (reactive) modes. It is shown that the eigenmode set for a
waveguiding structure is complete only outside the region of exciting sources.
Inside this region the modal expansions of fields are incomplete and must be
supplemented with the orthogonal complementary fields which extend the proper
Hilbert space spanned by waveguide eigenfunctions. Among exciting sources there
are the external bulk sources (currents, fields, and medium perturbations) and
the external surface currents. Besides, the orthogonal complementary fields
generate the effective surface currents on boundaries of the bulk exciting
sources. The problem of waveguide excitation by external sources is solved by
means of determining both the mode amplitudes for the modal field expansions
and the orthogonal complementary fields inside the source region. The equations
of mode excitation are derived on the basis of three approaches applying the
direct use of Maxwell's equations, the electrodynamic analogy with the
mathematical method of variation of constants, and the conjugate reciprocity
theorem.


title: Entropy Index as a Measure of Heartbeat Irregularity

abstract:
  A method is proposed to analyze the heartbeat waveform that can yield a
reliable characterization of the structure after only a few pulses. The measure
suggested is entropy index that is related to the one found effective in
describing chaotic behaviors in a wide variety of physical systems. When
applied to the ECG data that include ventricular fibrillation, the index is
shown to change drastically within a few pulses. Wavelet analysis is used to
exhibit different scaling behaviors in different phases.


title:
Electromagnetic Quantum Gravity: On the Quantum Principle of
  Equivalence, Quantum Inertia, and the Meaning of Mass

abstract:
  A new approach to Quantum Gravity is proposed that is manifestly compatible
with Cellular Automata (CA) theory, and is based on a new quantum theory of
inertia where Newtonian Inertia results from the electromagnetic forces between
the (electrically) charged elementary particles of an accelerated mass and the
surrounding (electrically) charged virtual particles of the quantum vacuum. At
the Plank scale, there exists a quantized, absolute 3D space and separate
(quantized) time which is not affected by motion or gravity. Light is the
simple shifting of a photon information pattern from cell to adjacent cell at
every CA 'clock cycle'. The Lorentz transformation is derived from our simple
model of light motion. Inertial mass is revised to acknowledge the absolute
nature of mass and acceleration. The same electromagnetic quantum vacuum forces
are also present in masses inside a gravitational field, where now the quantum
vacuum is accelerated with respect to the mass by graviton exchanges. This
process is responsible for the equivalence principle (WEP), which is derived in
detail. Gravity is found to be based on two boson force exchange particles: the
graviton and the photon, and both particles are postulated to be almost
identical in physical characteristics. 4D space-time curvature is found to
result from a 'Fizeau-like' scattering process, where the accelerated
(electrically charged) virtual particles of the quantum vacuum act like a
special 'Fizeau fluid'. Light scatters with the electrically charged and
accelerated 'Fizeau fluid', resulting in curved paths. Four experimental tests
of EMQG are proposed.


title: Intensity of Two-Photon Absorption Transitions for Ni2+ in MgO

abstract:
  The parity-allowed two-photon transitions between the ground state 3A2(T2) of
the configuration 3d8 in cubical symmetry and the excited states of the same
configuration are obtained via a simple model. This model is developed in a
symmetry adapted framework by using second-order mechanisms and ionic
wave-functions. It is applied to the recent experimental results obtained by
McClure and co-workers for Ni2+ in MgO.

categories: physics.atm-clus cond-mat.soft physics.chem-ph quant-ph


title:
Instability and `Sausage-String' Appearance in Blood Vessels during High
  Blood Pressure

abstract:
  A new Rayleigh-type instability is proposed to explain the `sausage-string'
pattern of alternating constrictions and dilatations formed in blood vessels
under influence of a vasoconstricting agent. Our theory involves the nonlinear
elasticity characteristics of the vessel wall, and provides predictions for the
conditions under which the cylindrical form of a blood vessel becomes unstable.


title:
Novel Reconstruction mechanisms: A comparison between group-III-nitrides
  and "traditional" III-V-semiconductors

abstract:
  We have studied the driving forces governing reconstructions on polar GaN
surfaces employing first-principles total-energy calculations. Our results
reveal properties not observed for other semiconductors, as for example a
strong tendency to stabilize Ga-rich surfaces. This mechanism is shown to have
important consequences on various surface properties: Novel and hitherto
unexpected structures are stable, surfaces may become metallic although GaN is
a wide-bandgap semiconductor, and the surface energy is significantly higher
than for other semiconductors. We explain these features in terms of the small
lattice constant of GaN and the unique bond strength of nitrogen molecules.


title: New Developments in Hybrid Photon Detectors

abstract:
  New developments in HPD design are presented, triggered by applications in
high energy physics and astrophysics. The presented HPD designs are based on
three innovations. (i) In order to achieve the highest possible surface
coverage in a RICH detector, we introduced a photoelectron focussing method
which is efficient to the periphery of the photocathode. (ii) To prevent
positive ion feedback in HPDs, we introduced a permanent potential barrier in
front of the anode. (iii) To replace a transmittive by a reflective
photocathode, we arrived at a conceptually new HPD design with surprisingly
good imaging characteristics, high quantum efficiency and low cost.


title: Scattering and resonances in the ^4He three-atomic system

abstract:
  A mechanism of disappearance and formation of the Efimov levels of the helium
^4He_3 trimer is studied when the force of interatomic interaction is changed.
The resonances including virtual levels are calculated by the method based on
the solving the boundary value problem, at complex energies, for the Faddeev
differential equations describing the (2+1 --> 2+1; 1+1+1) scattering
processes.


title:
Structure of T- and S-matrices in unphysical sheets and resonances in
  three-body systems

abstract:
  Algorithm, based on explicit representations for the analytic continuation of
Faddeev components of the three-body T-matrix in unphysical energy sheets, is
employed to study mechanism of disappearance and formation of the Efimov levels
of the helium ^4He trimer.


title:
Spontaneous curvature-induced dynamical instability of Kirchhoff
  filaments: Application to DNA kink deformations

abstract:
  The Kirchhoff elastic theory of thin filaments with spontaneous curvature is
employed in the understanding of the onset of the kink transitions observed in
short DNA rings. Dynamical analysis shows that when its actual curvature is
less than some threshold value determined by the spontaneous curvature, a
circular DNA will begin to buckle to other shapes. The observable and the
dominant deformation modes are also determined by dynamical instability
analysis, and the different effects of Zn$^{2+}$ and Mg$^{2+}$ ions on DNA
configurational properties are qualitatively discussed.

categories: physics.bio-ph cond-mat.soft physics.chem-ph q-bio


title: Locality, QED and Classical Electrodynamics

abstract:
  We report on some conceptual changes in our present understanding of Quantum
Field Theory and muse about possible consequences for the understanding of
$v>c$ signals.


title: Electron attachment to valence-excited CO

abstract:
  The possibility of electron attachment to the valence $^{3}\Pi$ state of CO
is examined using an {\it ab initio} bound-state multireference configuration
interaction approach. The resulting resonance has $^{4}\Sigma^{-}$ symmetry;
the higher vibrational levels of this resonance state coincide with, or are
nearly coincident with, levels of the parent $a^{3}\Pi$ state. Collisional
relaxation to the lowest vibrational levels in hot plasma situations might
yield the possibility of a long-lived CO$^-$ state.


title:
Special Relativity Derived from Cellular Automata Theory: The Origin of
  the Universal Speed Limit

abstract:
  A new formulation of Special Relativity is described. It is based on Cellular
Automata theory and on a new theory of inertia called Quantum Inertia. The
universe consists of a huge 3D array of cells given by C(x,y,z), whose numeric
states are updated by every new CA clock period. The numeric state of the cells
depends on the contents of the imediate neigbours and on the mathematical rules
of the cell, with each cell containing the same set of rules. Photon motion on
the CA is represented by information patterns 'shifting' from cell to adjacent
cell at every clock cycle, and this represents the universal speed limit. The
Lorentz Transformations follow directly from this model of light motion. The
concept of mass and inertia is revised to be compatible with the CA model.


title: Calculation of hyperfine structure constants for ytterbium

abstract:
  We calculate energies and hyperfine structure constants A and B for low-lying
levels of $^{173}$Yb. The latter is treated as a two-electron atom. To account
for valence-valence correlations the configuration interaction method is used.
Valence-core correlations are accounted for within the many-body perturbation
theory which is used to construct effective two-electron operators in the
valence space.


title:
Thomson Scattering of Coherent Diffraction Radiation by an Electron
  Bunch

abstract:
  The paper considers the process of Thomson scattering of coherent diffraction
radiation (CDR) produced by the preceding bunch of the accelerator on one of
the following bunches. It is shown that the yield of scattered hard photons is
proportional to N$_e^3$, where N$_e$ is the number of electrons per bunch. A
geometry is chosen for the CDR generation and an expression is obtained for the
scattered photon spectrum with regard to the geometry used, that depends in an
explicit form on the bunch size. A technique is proposed for measuring the
bunch length using scattered radiation characteristics.


title: Single-molecule spectroscopy near structured dielectrics

abstract:
  We present an analytical approach to the calculation of the linewidth and
lineshift of an atom or molecule in the near field of a structured dielectric
surface. For soft surface corrugations with amplitude lambda/50, we find
variations of the linewidth in the ten percent region. More strikingly, the
shift of the molecular resonance can reach several natural linewidths. We
demonstrate that the lateral resolution is of the order of the molecule-surface
distance. We give a semiquantitative explanation of the outcome of our
calculations that is based on simple intuitive models.


title: Search for low-dimensional chaos in a reversed field pinch plasma

abstract:
  An analysis of experimental data from the RFX (Reversed Field eXperiment)
reversed field pinch machine [L. Fellin, P. Kusstatscher and G. Rostagni,
Fusion Eng. Des. {\bf 25}, 315 (1995)] is carried out to investigate the
possible existence of deterministic chaos in the edge plasma region. The
mathematical tools used include Lyapunov exponents, Kaplan-Yorke dimension,
minimum embedding dimension estimates and nonlinear forecasting. The whole
analysis agrees in ruling out the possibility of low-dimensional chaos: The
dimension of the underlying dynamical system is estimated to be $ > 10$. From a
critical re-reading of the literature it emerges that the findings of this work
are likely to be common to all reversed field pinches.


title: Regular order reductions of ordinary and delay-differential equations

abstract:
  We present a C program to compute by successive approximations the regular
order reduction of a large class of ordinary differential equations, which
includes evolution equations in electrodynamics and gravitation. The code may
also find the regular order reduction of delay-differential equations.


title:
Theory of Circle Maps and the Problem of One-Dimensional Optical
  Resonator with a Periodically Moving Wall

abstract:
  We consider the electromagnetic field in a cavity with a periodically
oscillating perfectly reflecting boundary and show that the mathematical theory
of circle maps leads to several physical predictions. Notably, well-known
results in the theory of circle maps (which we review briefly) imply that there
are intervals of parameters where the waves in the cavity get concentrated in
wave packets whose energy grows exponentially. Even if these intervals are
dense for typical motions of the reflecting boundary, in the complement there
is a positive measure set of parameters where the energy remains bounded.

categories: physics.optics chao-dyn math-ph math.MP nlin.CD


title: Relativistic contraction of an accelerated rod

abstract:
  The relativistic motion of an arbitrary point of an accelerated rigid rod is
discussed for the case when velocity and acceleration are directed along the
rod's length. The discussion includes the case of a time-dependent force
applied to a single point, as well as a time-independent force arbitrary
distributed along the rod.
  The time dependence of the rod's relativistic length depends on the
application point of the force, but after the termination of acceleration the
final velocity and length do not depend on it. An observer on a uniformly
accelerated rod feels an inertial force which decreases in the direction of
acceleration. The influence of non-rigidity of realistic rods on our results is
qualitatively discussed.


title:
Estimating probability densities from short samples: a parametric
  maximum likelihood approach

abstract:
  A parametric method similar to autoregressive spectral estimators is proposed
to determine the probability density function (pdf) of a random set. The method
proceeds by maximizing the likelihood of the pdf, yielding estimates that
perform equally well in the tails as in the bulk of the distribution. It is
therefore well suited for the analysis short sets drawn from smooth pdfs and
stands out by the simplicity of its computational scheme. Its advantages and
limitations are discussed.


title:
Markov analysis of stochastic resonance in a periodically driven
  integrate-fire neuron

abstract:
  We model the dynamics of the leaky integrate-fire neuron under periodic
stimulation as a Markov process with respect to the stimulus phase. This avoids
the unrealistic assumption of a stimulus reset after each spike made in earlier
work and thus solves the long-standing reset problem. The neuron exhibits
stochastic resonance, both with respect to input noise intensity and stimulus
frequency. The latter resonance arises by matching the stimulus frequency to
the refractory time of the neuron. The Markov approach can be generalized to
other periodically driven stochastic processes containing a reset mechanism.


title: Self-trapping of Necklace beams in Self-focusing Kerr media

abstract:
  We show that an azimuthally-periodically-modulated bright ring "necklace"
beam can self-trap in self-focusing Kerr media and can exhibit stable
propagation for very large distances. These are the first bright (2+1) D beams
to exhibit stable self-trapping in a system described by the cubic (2+1) D
Nonlinear Schrodinger Equation (NLSE).


title:
Detecting periodicity in experimental data using linear modeling
  techniques

abstract:
  Fourier spectral estimates and, to a lesser extent, the autocorrelation
function are the primary tools to detect periodicities in experimental data in
the physical and biological sciences. We propose a new method which is more
reliable than traditional techniques, and is able to make clear identification
of periodic behavior when traditional techniques do not. This technique is
based on an information theoretic reduction of linear (autoregressive) models
so that only the essential features of an autoregressive model are retained.
These models we call reduced autoregressive models (RARM). The essential
features of reduced autoregressive models include any periodicity present in
the data. We provide theoretical and numerical evidence from both experimental
and artificial data, to demonstrate that this technique will reliably detect
periodicities if and only if they are present in the data. There are strong
information theoretic arguments to support the statement that RARM detects
periodicities if they are present. Surrogate data techniques are used to ensure
the converse. Furthermore, our calculations demonstrate that RARM is more
robust, more accurate, and more sensitive, than traditional spectral
techniques.


title:
Chaotic dynamics and coherent structure in electron beam with virtual
  cathode in the diode with local neutralization

abstract:
  The paper consider a complex dynamics of electron beam with virtual cathode
and local neutralization of the beam charge density near anode. Different types
of nonlinear behaviour, including deterministic chaos, were treated. It is
shown that chaotic dynamics arises as results of spatiotemporal structures
interaction.


title:
Catalog of the scientific manuscripts left by Ettore Majorana (with a
  Recollection of E.Majorana, sixty years after his disappearance)

abstract:
  Ettore Majorana, perhaps the greatest Italian theoretical physicist of this
century (Enrico Fermi compared him to Galilei and Newton), disappeared
misteriously from Naples in 1938, when he was 31. In the first part of this
work we outline his scientific personality (on the basis of letters, documents,
testimonies collected by us in about twenty years) and the significance of some
parts of his publications. In the second part of this paper we set forth some
brief information about the unpublished scientific manuscripts left by
E.Majorana and known to us till this moment (most of which are deposited at the
"Domus Galilaeana" in Pisa, Italy), and present a preliminary Catalogue of them
prepared in collaboration with M.Baldo and R.Mignani. [The present material is
mainly taken from our book "Il Caso Majorana: Epistolario, Documenti,
Testimonianze" (Mondadori, Milan, 1987,1991; Di Renzo, Rome, 2000-2008): We
address to such a book (c/o www.direnzo.it, "Arcobaleno" series) all the
readers interested in more and deeper information; as well as, for more
technical topics, to the subsequent volumes reproducing e.g. part of the
scientific manuscripts left unpublished by Ettore Majorana: see, for instance,
the e-print arXiv:0709.1183v1[physics.hist-ph].]


title:
Finite-Difference Investigation of Axisymmetric Inviscid Separated Flows
  with Infinitely-Long Cusp-Ended Stagnation Zone. Flow around a Sphere

abstract:
  The classical Helmholtz problem is applied for modelling the axisymmetric
inviscid cusp-ended separated flow around a sphere. Two coordinate systems are
employed: polar for initial calculations and parabolic the latter being more
suitable for investigation of infinitely-long stagnation zones. Scaled
coordinates are introduced and difference schemes for the free-stream equation
and the Bernoulli integral are devised. The separation point is not initially
prescribed and is defined iteratively. A separated flow with vanishing drag
coefficient is obtained.


title: Quantum Field Theoretic Derivation of the Einstein Equivalence Principle

abstract:
  We provide a derivation of the Einstein Weak Equivalence Principle (WEP)
based on our Quantum Field Theory (QFT) of the masseon and graviton particles
called ElectroMagnetic Quantum Gravity (EMQG, ref. 1). EMQG provides a
framework for understanding Newtonian Inertia as a pure QFT process involving
the photon as the vector boson exchange particle. Photons are exchanged between
the electrically charged masseon particles (which are the ultimate consistuents
of the fermion particles of ordinary matter, and contain electrical charge and
mass-charge) of an accelerated mass, and the electrically charged virtual
masseon particles of the quantum vacuum. The sum of all the tiny
electromagnetic forces contributed by each masseon particle of the mass from
the surrounding quantum vacuum is the source of the total inertial force of an
accelerated mass in Newton's F=MA. We found that gravity involves this same
process, where now the virtual masseons of the quantum vacuum are accelerated
by the graviton exchanges between the masseons in the earth (which have mass
charge) and the virtual masseons of the quantum vacuum (which also have mass
charge). Equivalence occurs because of the reversal of the roles of the quantum
vacuum and masseons in accelerated frames and under gravity. Equivalence is not
perfect. There is a tiny imbalance between gavitational mass and inertial mass
(in favor of gravity) caused by the direct graviton exchanges with the mass
(not present in inertial mass).


title:
Modeling of ions energy distribution profile of electronegative plasma
  discharges with an efficient Monte Carlo simulator

abstract:
  The crucial role that Ions Energy Distribution Function (IEDF) at the
electrodes plays in plasma processing of semiconductor materials demands that
this quantity be predicted with high accuracy and with low noise levels in any
plasma simulator. In this work, an efficient Particle-in-cell/Monte-Carlo
(PIC/MC) simulator is developed to model IEDF at the electrodes of
electronegative plasma discharges. The simulator uses an effective method to
increase the number of MC particles in regions of low particle density by
splitting the particles and by adjusting their statistical weight. This
statistical enhancement technique, which does not require interprocessor
communication, is particularly suitable for parallel processing. The simulator
is used to model an electronegative rf discharge at a pressure of 25 mTorr. The
IEDF obtained from this simulator has good statistics with low noise levels,
whereas the IEDF calculated by standard PIC/MC simulator is jammed with
stochastic noise.


title:
Analysis of low pressure electro-positive and electro-negative rf
  plasmas with Monte Carlo method

abstract:
  Particle-in-cell/Monte Carlo technique is used to simulate low pressure
electro-negative and electro-positive plasmas at a frequency of 10 MHz. The
potential, electric field, electron and ion density, and currents flowing
across the plasma are presented. To compare the physical properties of the
electro-positive gas with those of an electro-negative gas, the input voltage
was decreased from 1000 Volts to 350 Volts. The simulation results indicate
that the introduction of negative ions induces dramatic effects on the spatial
and temporal variation of the electric field and on the behavior of the
electron, ion, and displacement currents. In particular, the numerical modeling
predicts the formation of double-layer at the plasma-sheath boundary of
electro-negative discharge.


title:
Matter wave interference using two-level atoms and resonant optical
  fields

abstract:
  A theory of matter wave interference is developed in which resonant optical
fields interact with two-level atoms. When recoil effects are included, spatial
modulation of the atomic density can occur for times that are greater than or
comparable with the inverse recoil frequency. In this regime, the atoms exhibit
matter-wave interference. Two specific atom field geometries are considered. In
the first, atoms characterized by a homogeneous velocity distribution are
subjected to a single radiation pulse. The pulse excites the atoms which then
decay back to the lower state. The spatial modulation of the total atomic
density is calculated as a function of $t$, where $t$ is the time following the
pulse. In contrast to the normal Talbot effect, the spatially modulated density
is not a periodic function of $ t,$ owing to spontaneous emission; however,
after a sufficiently long time, the contribution from spontaneous processes no
longer plays a role and the Talbot periodicity is restored. In the second
atom-field geometry, there are two pulses separated by an interval $T$. The
atomic velocity distribution in this case is assumed to be inhomogeneously
broadened. In contrast to the normal Talbot-Lau effect, the spatially modulated
density is not a periodic function of $T$, owing to spontaneous emission;
however, for sufficiently long time, the contribution from spontaneous
processes no longer plays a role and the Talbot periodicity is restored. The
structure of the spatially modulated density is studied, and is found to mirror
the atomic density following the first pulse. The spatially modulated atomic
density serves as an indirect probe of the distribution of spontaneously
emitted radiation.


title: Efficient Monte Carlo Methods for Cyclic Peptides

abstract:
  We present a new, biased Monte Carlo scheme for simulating complex, cyclic
peptides. Backbone atoms are equilibrated with a biased rebridging scheme, and
side-chain atoms are equilibrated with a look-ahead configurational bias Monte
Carlo. Parallel tempering is shown to be an important ingredient in the
construction of an efficient approach.


title:
Guided random walk calculation of energies and $<\sq {r^2} >$ values of
  the $^1\Sigma_g$ state of H_2 in a magnetic field

abstract:
  Energies and spatial observables for the $^1\Sigma_g$ state of the hydrogen
molecule in magnetic fields parallel to the proton-proton axis are calculated
with a guided random walk Feynman-Kac algorithm. We demonstrate that the
accuracy of the results and the simplicity of the method may prove it a viable
alternative to large basis set expansions for small molecules in applied
fields.


title: Rearrangements of Water Dimer and Hexamer

abstract:
  Rearrangement mechanisms of the water dimer and the cage form of the water
hexamer are examined theoretically with particular reference to tunneling
splittings and spectroscopy. The three lowest barrier rearrangements of the
water dimer are characterized by {\it ab initio} methods and compared with the
results of previous constrained calculations. The acceptor-tunneling pathway
does not proceed via a direct rotation around the $C_2$ axis of the acceptor,
but rather via relatively asynchronous rotation of the donor about the hydrogen
bond and an associated `wag' of the acceptor. Rearrangements between different
cage isomers of the water hexamer are studied for two empirical potentials. The
experimentally observed triplet splittings may be the result of flip and
bifurcation rearrangements of the two single-donor, single-acceptor monomers.
Two-dimensional quantum calculations of the nuclear dynamics suggest that
delocalization over more than one cage isomer may occur, especially in excited
states.


title: Rearrangements and Tunneling Splittings in Small Water Clusters

abstract:
  Recent far-infrared vibration-rotation tunneling (FIR-VRT) experiments pose
new challenges to theory because the interpretation and prediction of such
spectra requires a detailed understanding of the potential energy surface (PES)
away from minima. In particular we need a global description of the PES in
terms of a complete reaction graph. Hence all the transition states and
associated mechanisms which might give rise to observable tunneling splittings
must be characterized. It may be possible to guess the detailed permutations of
atoms from the transition state alone, but experience suggests this is unwise.
  In this contribution a brief overview of the issues involved in treating the
large amplitude motions of such systems will be given, with references to more
detailed discussions and some specific examples. In particular we will consider
the effective molecular symmetry group, the classification of rearrangement
mechanisms, the location of minima and transition states and the calculation of
reaction pathways. The application of these theories to small water clusters
ranging from water dimer to water hexamer will then be considered. More details
can be found in recent reviews.


title: Simulation and analysis of electron cyclotron resonance discharges

abstract:
  We describe in detail the method for Particle-in cell/Monte-Carlo simulation
of electron cyclotron resonance (ECR) discharges. In the simulation, electric
and magnetic fields are obtained by solving Maxwell equations, and electrons
and ions are accelerated by solving equations of motion. We consider two
different cases: (i) propagation of electromagnetic wave in the presence of a
constant external magnetic field; (ii) propagation of electromagnetic wave in
the presence of a linearly decreasing magnetic field which corresponds to a
realistic ECR discharge. The simulation results indicate that at the resonance
layer, the electrons are heated by the electromagnetic wave, and the incoming
wave amplitude is pronouncedly damped, with the wave hardly propagating through
the ECR layer.


title:
From circular paths to elliptic orbits: A geometric approach to Kepler's
  motion

abstract:
  The hodograph, i.e. the path traced by a body in velocity space, was
introduced by Hamilton in 1846 as an alternative for studying certain dynamical
problems. The hodograph of the Kepler problem was then investigated and shown
to be a circle, it was next used to investigate some other properties of the
motion. We here propose a new method for tracing the hodograph and the
corresponding configuration space orbit in Kepler's problem starting from the
initial conditions given and trying to use no more than the methods of
synthetic geometry in a sort of Newtonian approach. All of our geometric
constructions require straight edge and compass only.


title:
The Scaling Behaviour of Stochastic Minimization Algorithms in a Perfect
  Funnel Landscape

abstract:
  We determined scaling laws for the numerical effort to find the optimal
configurations of a simple model potential energy surface (PES) with a perfect
funnel structure that reflects key characteristics of the protein interactions.
Generalized Monte-Carlo methods(MCM, STUN) avoid an enumerative search of the
PES and thus provide a natural resolution of the Levinthal paradox. We find
that the computational effort grows with approximately the eighth power of the
system size for MCM and STUN, while a genetic algorithm was found to scale
exponentially. The scaling behaviour of a derived lattice model is also
rationalized.


title: Experimental observation of nonlinear Thomson scattering

abstract:
  A century ago, J. J. Thomson showed that the scattering of low-intensity
light by electrons was a linear process (i.e., the scattered light frequency
was identical to that of the incident light) and that light's magnetic field
played no role. Today, with the recent invention of ultra-high-peak-power
lasers it is now possible to create a sufficient photon density to study
Thomson scattering in the relativistic regime. With increasing light intensity,
electrons quiver during the scattering process with increasing velocity,
approaching the speed of light when the laser intensity approaches 10^18
W/cm^2. In this limit, the effect of light's magnetic field on electron motion
should become comparable to that of its electric field, and the electron mass
should increase because of the relativistic correction. Consequently, electrons
in such high fields are predicted to quiver nonlinearly, moving in figure-eight
patterns, rather than in straight lines, and thus to radiate photons at
harmonics of the frequency of the incident laser light, with each harmonic
having its own unique angular distribution. In this letter, we report the first
ever direct experimental confirmation of these predictions, a topic that has
previously been referred to as nonlinear Thomson scattering. Extension of these
results to coherent relativistic harmonic generation may eventually lead to
novel table-top x-ray sources.


title: A Proposal to Revise the Macroscopic Electromagnetic Theory

abstract:
  There are reasons to believe that implications of a certain paradox
introduced by Ginzburg and related problems have not been fully recognized.
Pertinent issues remain open and unresolved. There are instances when the
current widely used theory yields results having no physical meaning. As a
result, the current widely used theory is not equipped to cope with some of the
most fundamental problems in physics. In the present investigation, a new
formulation is proposed based on certain non-Maxwellian quantities which occur
whenever there is absorption. In the proposed formulation, the inconsistencies
and contradictions disclosed by the Ginzburg Paradox have been removed.


title: Autler - Townes doublet probed by strong field

abstract:
  This paper deals with the Autler - Townes doublet structure. Applied driving
and probing laser fields can have arbitrary intensities. The explanation is
given of the broadening of doublet components with the growth of probing field
intensity, which was observed in experiment. The effects of Doppler averaging
are discussed.


title: Is the number of Photons a Classical Invariant?

abstract:
  We describe an apparent puzzle in classical electrodynamics and its
resolution. It is concerned with the Lorentz invariance of the classical analog
of the number of photons.


title: How to observe the Efimov effect

abstract:
  We propose to observe the Efimov effect experimentally by applying an
external electric field on atomic three-body systems. We first derive the
lowest order effective two-body interaction for two spin zero atoms in the
field. Then we solve the three-body problem and search for the extreme
spatially extended Efimov states. We use helium trimers as an illustrative
numerical example and estimate the necessary field strength to be less than 2.7
V/angstrom.


title:
Minimizing postulation in a senior undergraduate course in
  electromagnetism

abstract:
  An approach to the teaching of electromagnetism to senior undergraduate
students, designed for overcoming the fragmentation of the theory is described.
As usual it starts from the static case, but it is strictly based on Helmholtz
theorem of uniqueness of vector fields, on primary experimental observations
upon the sources of electric and magnetic fields, on Lenz's law and on
principles of superposition and reciprocity of interactions. Thereafter,
without further postulation, all laws and rules arise in a procedure where
electricity and magnetism parallel one another. Maxwell's equations are built
up on a step-by-step basis, showing that electromagnetic field can be
considered but a twofold linear vector field obeying the simplest principles of
physical theories. It is shown that every system of units fits this formalism,
provided suitable values are assigned to some constants arising therein from
superposition principle.


title: Searching for Shakespeare in the Stars

abstract:
  The question of the authorship of Shakespeare's plays has long been debated.
The two leading contenders are W. Shakspere (1564-1616) and Edward de Vere the
13th Earl of Oxford (1550-1604). Here I note that Shakespeare's references to
important events and discoveries in astronomy and geophysics in 1572 and 1600,
but not to similarly important events of 1604, 1609 and 1610, especially given
Shakespeare's frequent references to and knowledge of the physical sciences,
might be able to shed some light on the authorship question.