title: On the Nature of Quantum Phenomena

abstract:
  It is shown that a coherent understanding of all quantized phenomena,
including those governed by unitary evolution equations as well as those
related to irreversible quantum measurements, can be achieved in a scenario of
successive nonequilibrium phase transitions, with the lowest hierarchy of these
phase transitions occurring in a ``resonant cavity'' formed by the entire
matter and energy content of the universe. In this formalism, the physical laws
themselves are resonantly-selected and ordered in the universe cavity in a
hierarchical manner, and the values of fundamental constants are determined
through a Generalized Mach's Principle. The existence of a preferred reference
frame in this scenario is shown to be consistent with the relational nature of
the origin of physical laws. Covariant unitary evolution is shown to connect
smoothly with the reduction of wavefunction in the preferred frame during
quantum measurement. The superluminal nature of quantum processes in the lowest
hierarchy coexists with the universal speed limit obeyed by processes in higher
hierarchies. A natural quantum-to-classical transition is also obtained which
is stable against the diffusive tendency of the unitary quantum evolution
processes. In this formalism a realistic quasi-classical ontology is
established for the foundations of quantum mechanics.


title: Quantum Interference Effects in InAs Semiconductor Nanowires

abstract:
  We report quantum interference effects in InAs semiconductor nanowires
strongly coupled to superconducting electrodes. In the normal state, universal
conductance fluctuations are investigated as a function of magnetic field,
temperature, bias and gate voltage. The results are found to be in good
agreement with theoretical predictions for weakly disordered one-dimensional
conductors. In the superconducting state, the fluctuation amplitude is enhanced
by a factor up to ~ 1.6, which is attributed to a doubling of charge transport
via Andreev reflection. At a temperature of 4.2 K, well above the Thouless
temperature, conductance fluctuations are almost entirely suppressed, and the
nanowire conductance exhibits anomalous quantization in steps of e^{2}/h.


title: P-symbols, Heun Identities, and 3F2 Identities

abstract:
  The usefulness of Riemann P-symbols in deriving identities involving the
parametrized special function Hl is explored. Hl is the analytic local solution
of the Heun equation, the canonical second-order differential equation on the
Riemann sphere with four regular singular points. The identities discussed
include ones coming from Moebius automorphisms and F-homotopies, and also
quadratic and biquadratic transformations. The case when Hl is identical to a
generalized hypergeometric function of 3F2 type is examined, and Pfaff and
Euler transformations of 3F2(a1,a2,e+1;b1,e;x) are derived. They extend several
3F2 identities of Bailey and Slater.


title: Charges on Strange Quark Nuggets in Space

abstract:
  Since Witten's seminal 1984 paper on the subject, searches for evidence of
strange quark nuggets (SQNs) have proven unsuccessful. In the absence of
experimental evidence ruling out SQNs, the validity of theories introducing
mechanisms that increase their stability should continue to be tested. To
stimulate electromagnetic SQN searches, particularly space searches, we
estimate the net charge that would develop on an SQN in space exposed to
various radiation baths (and showers) capable of liberating their less strongly
bound electrons, taking into account recombination with ambient electrons. We
consider, in particular, the cosmic background radiation, radiation from the
sun, and diffuse galactic and extragalactic $\gamma $-ray backgrounds. A
possible dramatic signal of SQNs in explosive astrophysical events is noted.


title: Embeddings for 4D Einstein equations with a cosmological constant

abstract:
  There are many ways of embedding a 4D spacetime in a given higher-dimensional
manifold while, satisfying the field equations. In this work we extend and
generalize a recent paper by Mashhoon and Wesson ({\it Gen. Rel. Gravit.} {\bf
39}, 1403(2007)) by showing different ways of embedding a solution of the 4D
Einstein equations, in vacuum with a cosmological constant, in a Ricci-flat, as
well as in an anti-de Sitter, 5D manifold. These embeddings lead to different
physics in 4D. In particular, to non-equivalent cosmological terms as functions
of the extra coordinate. We study the motion of test particles for different
embeddings and show that there is a complete equivalence between several
definitions for the effective mass of test particles measured in 4D, obtained
from different theoretical approaches like the Hamilton-Jacobi formalism and
the principle of least action. For the case under consideration, we find that
the effective mass observed in 4D is the same regardless of whether we consider
null or non-null motion in 5D.


title:
Holomorphic L^{p}-functions on Coverings of Strongly Pseudoconvex
  Manifolds

abstract:
  In this paper we will show how to construct holomorphic L^{p}-functions on
unbranched coverings of strongly pseudoconvex manifolds. Also, we prove some
extension and approximation theorems for such functions.


title:
Quantum-noise-limited Angular Momentum Measurement for a Micron-sized
  Dielectric Object

abstract:
  An approach is described for observing quantum features of micron-sized
spinning objects. Specifically, we consider a birefringent (uniaxial positive)
dielectric object in the shape of an oblate (i.e., frisbee-like) symmetric top.
It can be trapped in the air, its extraordinary axis can be aligned, and its
angular momentum along the extraordinary axis can be stabilized, all optically.
We show that the angular momentum quantum noise of the object perpendicular to
the gigantic angular momentum along the extraordinary axis can be measured as a
linear birefringent phase shift of a probe laser in an analogous fashion to the
spin quantum nondemolition (QND) measurement in atomic physics.


title: Traffic of single-headed motor proteins KIF1A: effects of lane changing

abstract:
  KIF1A kinesins are single-headed motor proteins which move on cylindrical
nano-tubes called microtubules (MT). A normal MT consists of 13 protofilaments
on which the equispaced motor binding sites form a periodic array. The
collective movement of the kinesins on a MT is, therefore, analogous to
vehicular traffic on multi-lane highways where each protofilament is the
analogue of a single lane. Does lane-changing increase or decrease the motor
flux per lane? We address this fundamental question here by appropriately
extending a recent model [{\it Phys. Rev. E {\bf 75}, 041905 (2007)}]. By
carrying out analytical calculations and computer simulations of this extended
model, we predict that the flux per lane can increase or decrease with the
increasing rate of lane changing, depending on the concentrations of motors and
the rate of hydrolysis of ATP, the ``fuel'' molecules. Our predictions can be
tested, in principle, by carrying out {\it in-vitro} experiments with
fluorescently labelled KIF1A molecules.


title: One way cuts in oriented graphs

abstract: This paper has been withdrawn by the author.


title:
An exact calculation of the transverse susceptibility for an
  antiferromagnetic Ising $\Delta$ chain

abstract:
  We study the transverse susceptibility of the fully frustrated
antiferromagnetic Ising $\Delta$-chain, extending Minami's transfer-matrix
method for the transverse susceptibility of general-type Ising linear-chains
[JPSJ 67,1998,2255]. For transverse fields $\Gamma_1$ on tip spin sites and
$\Gamma_2$ on bottom spin sites, we calculate zero-field
transverse-susceptibilities $\chi_{tip}^x=\lim_{\Gamma_1,\Gamma_2 ->
0}M_{tip}^x/\Gamma_1$ and $\chi_{bottom}^x=\lim_{\Gamma_1,\Gamma_2 ->
0}M^x_{bottom}/\Gamma_2$, where $M_{tip (bottom)}^x$ denotes the magnetization
for tip (bottom) spin sites. Both the transverse susceptibilities follow
Curie's law at low temperatures. We also calculate
$\chi_{bottom}^x(\Gamma_1>0)$, transverse susceptibility of the bottom spin
chain under finite tip-spin transverse-fields, to understand the Curie type
behavior in the zero-field susceptibility. Using the second-order perturbation
theory, we discuss the $\Gamma_1$ dependence of $\chi_{bottom}^x(\Gamma_1)$ at
zero temperature.


title:
Erratum: Landau Analysis of the Symmetry of the Magnetic Structure and
  Magnetoelectric Interaction in Multiferroics [Phys. Rev. B 76, 05447 (2007)]

abstract:
  An error in the spin wavefunction for the rare earth sublattices of TbMn_2O_5
is corrected.


title:
Half Semimetallic Antiferromagnetism in the Sr$_2$CrTO$_6$ System, T=Os,
  Ru

abstract:
  Double perovskite Sr$_2$CrOsO$_6$ is (or is very close to) a realization of a
spin-asymmetric semimetallic compensated ferrimagnet, according to first
principles calculations. This type of near-half metallic antiferromagnet is an
unusual occurrence, and more so in this compound because the zero gap is
accidental rather than being symmetry determined. The large spin-orbit coupling
(SOC) of osmium upsets the spin balance (no net spin moment without SOC): it
reduces the Os spin moment by 0.27 $\mu_B$ and induces an Os orbital moment of
0.17 $\mu_B$ in the opposite direction. The effects combine (with small oxygen
contributions) to give a net total moment of 0.54 $\mu_B$ per cell in \scoo,
reflecting a large impact of SOC in this compound. This value is in moderately
good agreement with the measured saturation moment of 0.75 $\mu_B$. The value
of the net moment on the Os ion obtained from neutron diffraction (0.73 $\mu_B$
at low temperature) differs from the calculated value (1.14 $\mu_B$). Rather
surprisingly, in isovalent Sr$_2$CrRuO$_6$ the smaller SOC-induced spin changes
and orbital moments (mostly on Ru) almost exactly cancel. This makes
Sr$_2$CrRuO$_6$ a "half (semi)metallic antiferromagnet" (practically vanishing
net total moment) even when SOC is included, with the metallic channel being a
small-band-overlap semimetal. Fixed spin moment (FSM) calculations are
presented for each compound, illustrating how they provide different
information than in the case of a nonmagnetic material. These FSM results
indicate that the Cr moment is an order of magnitude stiffer against
longitudinal fluctuations than is the Os moment.


title:
Effects of electron-phonon coupling in angle-resolved photoemission
  spectra of SrTiO3

abstract:
  We have studied the O 2p valence-band structure of Nb-doped SrTiO3, in which
a dilute concentration of electrons are doped into the d0 band insulator, by
angle-resolved photoemission spectroscopy (ARPES) measurements. We found that
ARPES spectra at the valence band maxima at the M [k = (pi/a, pi/a, 0)]and R [k
= (pi/a, pi/a, pi/a)] points start from ~ 3.3 eV below the Fermi level (EF),
consistent with the indirect band gap of 3.3 eV and the EF position at the
bottom of the conduction band. The peak position of the ARPES spectra were,
however, shifted toward higher binding energies by ~ 500 meV from the 3.3 eV
threshold. Because the bands at M and R have pure O 2p character, we attribute
this ~ 500 meV shift to strong coupling of the oxygen p hole with optical
phonons in analogy with the peak shifts observed for d-electron photoemission
spectra in various transition-metal oxides.


title:
1122 Hz rotation of XTE J1739-285 as a probe of quark matter in the
  interior of the neutron star

abstract:
  The recent discovery of burst oscillation at 1122Hz in the X-ray transient
XTE J1739-285 supports the suggestion that it contains a submillisecond pulsar.
In our estimations of the enormous dissipation effect in the transition
boundary layer between quark matter core and hadron matter envelope, combing
the viscosities of bulk mater in previous works, we show that XTE J1739-285 can
be uniquely restricted to a quark star masquerading as a neutron star (hybrid
star) that contains a pure quark matter or mixed quark-hadron matter core from
minimizing gravitational wave radiation (r-mode) instability and Keplerian
motion constraints at 1122Hz level through a three-parameters image. Such
constraints allow the stellar radii in the range $9{\rm km}\leq R\leq 12{\rm
km}$ and the stellar masses in the range $1.2M_\odot\leq M\leq 2.0M_\odot$. It
perhaps implies that submillisecond pulsars are just probes of quark matter.


title:
Closure tests for mean field magnetohydrodynamics using a self
  consistent reduced model

abstract:
  The mean electromotive force and alpha effect are computed for a forced
turbulent flow using a simple nonlinear dynamical model. The results are used
to check the applicability of two basic analytic ansatze of mean-field
magnetohydrodynamics - the second order correlation approximation (SOCA) and
the tau approximation. In the numerical simulations the effective Reynolds
number Re is 2-20, while the magnetic Prandtl number varies from 0.1 to
$10^{7}$. We present evidence that the $\tau$ approximation may be appropriate
in dynamical regimes where there is a small-scale dynamo. Catastrophic
quenching of the $\alpha$ effect is found for high $P_{m}$. Our results
indicate that for high $P_{m}$ SOCA gives a very large value of the $\alpha$
coefficient compared with the ``exact'' solution. The discrepancy depends on
the properties of the random force that drives the flow, with a larger
difference occuring for $\delta$-correlated force compared with that for a
steady random force.


title:
Modeling The Structure And Dynamics of Dwarf Spheroidal Galaxies with
  Dark Matter And Tides

abstract:
  We report the results of N-body simulations of disrupting satellites aimed at
exploring whether the observed features of dSphs can be accounted for with
simple, mass-follows-light (MFL) models including tidal disruption. As a test
case, we focus on the Carina dwarf Spheroidal (dSph), which presently has the
most extensive data at large radius. We find that previous N-body, MFL
simulations of dSphs did not sufficiently explore the parameter space of
satellite mass, density and orbital shape to find adequate matches to Galactic
dSph systems, whereas with a systematic survey of parameter space we are able
to find tidally disrupting, MFL satellite models that rather faithfully
reproduce Carina's velocity profile, velocity dispersion profile and projected
density distribution over its entire sampled radius. The successful MFL model
satellites have very eccentric orbits, currently favored by Cold Dark Matter
(CDM) models, and central velocity dispersions that still yield an accurate
representation of the bound mass and observed central M/L~40 of Carina, despite
inflation of the velocity dispersion outside the dSph core by unbound debris.
Our survey of parameter space also allows us to address a number of commonly
held misperceptions of tidal disruption and its observable effects on dSph
structure and dynamics. The simulations suggest that even modest tidal
disruption can have a profound effect on the observed dynamics of dSph stars at
large radii. Satellites that are well-described by tidally disrupting MFL
models could still be fully compatible with L-CDM if for example they represent
a later stage in the evolution of luminous subhalos.


title:
Nuclear/Circumnuclear Starbursts and Active Galactic Nuclei Mass
  Accretion in Seyfert Galaxies

abstract:
  We investigated the correlation between nuclear/circumnuclear starbursts
around the active galactic nuclei (AGNs) and the AGN activities for 43 Seyfert
galaxies in the CfA and 12 micron samples. We found that circumnuclear
starburst luminosity as well as nuclear starburst luminosity are positively
correlated with AGN luminosity. Moreover, nuclear starburst luminosity is more
strongly correlated with the AGN luminosity normalized with AGN Eddington
luminosity than is circumnuclear starburst luminosity. This implies that
starbursts nearer the AGN could have a greater effect on AGN mass accretion. We
also discuss these results from the viewpoint of the radiation effects from
starbursts and sequential starbursts.


title:
Probing Nonstandard Neutrino Physics by Two Identical Detectors with
  Different Baselines

abstract:
  The Kamioka-Korea two detector system is a powerful experimental setup for
resolving neutrino parameter degeneracies and probing CP violation in neutrino
oscillation. In this paper, we study sensitivities of this same setup to
several nonstandard neutrino physics such as quantum decoherence, tiny
violation of Lorentz symmetry, and nonstandard interactions of neutrinos with
matter. In most cases, the Kamioka-Korea two-detector setup is more sensitive
than the one-detector setup, except for the Lorentz symmetry violation with CPT
violation, and the nonstandard neutrino interactions with matter. It can
achieve significant improvement on the current bounds on nonstandard neutrino
physics.


title:
A Cuspidality Criterion for the Exterior Square Transfer of Cusp Forms
  on GL(4)

abstract:
  For a cuspidal automorphic representation \Pi of GL(4,A), H. Kim proved that
the exterior square transfer \wedge^2\Pi is an isobaric automorphic
representation of GL(6,A). In this paper we characterize those representations
\Pi for which \wedge^2\Pi is cuspidal.


title:
Geometric phases and the magnetization process in quantum
  antiferromagnets

abstract:
  The physics underlying the magnetization process of quantum antiferromagnets
is revisited from the viewpoint of geometric phases. A continuum variant of the
Lieb-Schultz-Mattis-type approach to the problem is put forth, where the
commensurability condition of Oshikawa {\it et al} derives from a Berry
connection formulation of the system's crystal momentum. %, similar to that
developed by Haldane for ferromagnets. %Building on the physical picture which
arises, We then go on to formulate an effective field theory which can deal
with higher dimensional cases as well. We find that a topological term, whose
principle function is to assign Berry phase factors to space-time vortex
objects, ultimately controls the magnetic behavior of the system. We further
show how our effective action maps into a ${\bf Z}_2$ gauge theory under
certain conditions, which in turn allows for the occurrence of a fractionalized
phase with topological order.


title:
The Finite Difference Time Domain Method for Computing Single-Particle
  Density Matrix

abstract:
  A general method for numerical computation of the thermal density matrix of a
single-particle quantum system is presented. The Schrodinger equation in
imaginary time tau is solved numerically by the finite difference time domain
(FDTD) method using a set of initial wave functions at tau=0 . By choosing this
initial set appropriately, the set of wave functions generated by the FDTD
method can be used to construct the thermal density matrix. The theoretical
basis of the method, a numerical algorithm for its implementation, and
illustrative examples in one, two and three dimensions are given in this paper.
The numerical results show that the procedure is efficient and accurately
determines the density matrix and thermodynamic properties of single-particle
systems. Extensions of the method to more general cases are briefly indicated.


title:
Convergence of Expected Utilities with Algorithmic Probability
  Distributions

abstract:
  We consider an agent interacting with an unknown environment. The environment
is a function which maps natural numbers to natural numbers; the agent's set of
hypotheses about the environment contains all such functions which are
computable and compatible with a finite set of known input-output pairs, and
the agent assigns a positive probability to each such hypothesis. We do not
require that this probability distribution be computable, but it must be
bounded below by a positive computable function. The agent has a utility
function on outputs from the environment. We show that if this utility function
is bounded below in absolute value by an unbounded computable function, then
the expected utility of any input is undefined. This implies that a computable
utility function will have convergent expected utilities iff that function is
bounded.


title: Recent RXTE/ASM and ROTSEIIId Observations of EXO 2030+375

abstract:
  Using the archival RXTE/ASM and SWIFT/BAT observations, the new orbital
phases of Type I outbursts of EXO 2030+375 are estimated. A possible
correlation between the Type II outburst and optical brightness variations is
investigated. In order to estimate the phases of Type I outbursts, we fitted
Gaussian profiles to the RXTE/ASM and SWIFT/BAT light curves. The time
corresponding to the maximum value of the profiles is treated as the arrival
time of Type I outburst. We used differential magnitudes in the time-series
analysis of the optical light curve. MIDAS and its suitable packages were used
to reduce and analyze the spectra. Prior to the Type II outburst, orbital
phases of Type I outbursts were delayed for 6 days after the periastron
passage, which is consistent with findings of Wilson et al., (2002, 2005).
After the giant Type II outburst, the phase of Type I outbursts underwent a
sudden shift of 13 days after the periastron passage. The amplitudes of Type I
outbursts were increased between MJD 52500 and 53500. These amplitudes then
decreased for 10 orbital cycles until the Type II outburst was triggered. If
the change of outburst amplitudes correlated with the mass accretion, then
during the decrease of these amplitudes mass should be deposited in a disk
around neutron star temporarily. The release of this stored mass may ignite the
Type II outburst. We report that the optical light curve became fainter by 0.4
mag during the decrease of amplitude of the Type I outbursts. The observed
H$\alpha$ profiles and their equivalent widths during the decay and after the
giant outburst are consistent with previous observations of the system.


title:
Efficiency of higher dimensional Hilbert spaces for the violation of
  Bell inequalities

abstract:
  We have determined numerically the maximum quantum violation of over 100
tight bipartite Bell inequalities with two-outcome measurements by each party
on systems of up to four dimensional Hilbert spaces. We have found several
cases, including the ones where each party has only four measurement choices,
where two dimensional systems, i.e., qubits are not sufficient to achieve
maximum violation. In a significant proportion of those cases when qubits are
sufficient, one or both parties have to make trivial, degenerate 'measurements'
in order to achieve maximum violation. The quantum state corresponding to the
maximum violation in most cases is not the maximally entangled one. We also
obtain the result, that bipartite quantum correlations can always be reproduced
by measurements and states which require only real numbers if there is no
restriction on the size of the local Hilbert spaces. Therefore, in order to
achieve maximum quantum violation on any bipartite Bell inequality (with any
number of settings and outcomes), there is no need to consider complex Hilbert
spaces.


title: Subsystem Code Constructions

abstract:
  Subsystem codes are the most versatile class of quantum error-correcting
codes known to date that combine the best features of all known passive and
active error-control schemes. The subsystem code is a subspace of the quantum
state space that is decomposed into a tensor product of two vector spaces: the
subsystem and the co-subsystem. A generic method to derive subsystem codes from
existing subsystem codes is given that allows one to trade the dimensions of
subsystem and co-subsystem while maintaining or improving the minimum distance.
As a consequence, it is shown that all pure MDS subsystem codes are derived
from MDS stabilizer codes. The existence of numerous families of MDS subsystem
codes is established. Propagation rules are derived that allow one to obtain
longer and shorter subsystem codes from given subsystem codes. Furthermore,
propagation rules are derived that allow one to construct a new subsystem code
by combining two given subsystem codes.


title:
Spectral resolution in hyperbolic orbifolds, quantum chaos, and
  cosmology

abstract:
  We present a few subjects from physics that have one in common: the spectral
resolution of the Laplacian.


title: Dispersion Models for Extremes

abstract:
  We propose extreme value analogues of natural exponential families and
exponential dispersion models, and introduce the slope function as an analogue
of the variance function. The set of quadratic and power slope functions
characterize well-known families such as the Rayleigh, Gumbel, power, Pareto,
logistic, negative exponential, Weibull and Fr\'echet. We show a convergence
theorem for slope functions, by which we may express the classical extreme
value convergence results in terms of asymptotics for extreme dispersion
models. The main idea is to explore the parallels between location families and
natural exponential families, and between the convolution and minimum
operations.


title: Hybrid-impurity resonances in anisotropic quantum dots

abstract:
  The absorption of electromagnetic radiation of an anisotropic quantum dot is
theoretically investigated taking into account the processes associated with
simultaneous scattering from ionized impurities. It is shown that the
scattering of electrons by impurities leads to the resonance absorption even if
we have only one impurity in the quantum dot. Explicit formula is derived for
the absorption coefficient. The positions of the resonances peaks are found.
The effects of external magnetic field on the resonance absorption are studied.


title: Deformations of Compact Coassociative 4-folds with Boundary

abstract:
  Coassociative 4-folds are a particular class of 4-dimensional submanifolds
which are defined in a 7-dimensional manifold M with a G_2 structure given by a
`positive' differential 3-form, sometimes called G_2-form. Assuming that a
G_2-form on M is closed, we study deformations of a compact coassociative
submanifold N with boundary contained in fixed, codimension 1 submanifold S of
M with a compatible Hermitian symplectic structure. We show that `small'
coassociative deformations of N with special Lagrangian boundary in S are
unobstructed and form a smooth moduli space of finite dimension not greater
than the first Betti number of the boundary of N. It is also shown that N is
`stable' under small deformations of the closed G_2-form on the ambient
7-manifold M. The results can be compared to those for special Lagrangian
submanifolds of Calabi--Yau manifolds proved by A.Butscher in math.DG/0110052.


title: A Random Matrix Model of Black Holes

abstract:
  A random matrix model of black holes is given based on analysis of Gaussian
complex ensembles, based on the generalization of chRMT of QCD. Spacetime
freedoms are incorporated in terms of eigenvalues of the ensemble. Classical
observables of black holes can be computed using this model and it satisfies
asymptotic freedom and holographic principle.


title:
Primordial Helium Abundance from CMB: a constraint from recent
  observations and a forecast

abstract:
  We studied a constraint on the primordial helium abundance Y_p from current
and future observations of CMB. Using the currently available data from WMAP,
ACBAR, CBI and BOOMERANG, we obtained the constraint as Y_p =
0.25^{+0.10}_{-0.07} at 68% C.L. We also provide a forecast for the Planck
experiment using the Markov chain Monte Carlo approach. In addition to
forecasting the constraint on Y_p, we investigate how assumptions for Y_p
affect constraints on the other cosmological parameters.


title: Azimuthal and Single Spin Asymmetries in Hard Scattering Processes

abstract:
  In this article we review the present understanding of azimuthal and single
spin asymmetries for inclusive and semi-inclusive particle production in
unpolarized and polarized hadronic collisions at high energy and moderately
large transverse momentum. After summarizing the experimental information
available, we discuss and compare the main theoretical approaches formulated in
the framework of perturbative QCD. We then present in some detail a
generalization of the parton model with inclusion of spin and intrinsic
transverse momentum effects. In this context, we extensively discuss the
phenomenology of azimuthal and single spin asymmetries for several processes in
different kinematical configurations. A comparison with the predictions of
other approaches, when available, is also given. We finally emphasize some
relevant open points and challenges for future theoretical and experimental
investigation.


title:
On the value-semigroup of a simple complete ideal in a two-dimensional
  regular local ring

abstract:
  Let R be a two-dimensional regular local ring with maximal ideal \mathfrak m,
and let \wp be a simple complete \mathfrak m-primary ideal which is residually
rational. Let R_0:= R\subsetneqq ...\subsetneqq R_r be the quadratic sequence
associated to \wp, let \Gamma_\wp be the value-semigroup associated to \wp, and
let ((e_j(\wp))_{0\leq j\leq r} be the multiplicity sequence of \wp. We
associate to \wp a sequence of natural integers, the formal characteristic
sequence of \wp, and we show that the value-semigroup, the multiplicity
sequence and the formal characteristic sequence are equivalent data.
Furthermore, we give a new proof that \Gamma_\wp is symmetric, and give a
formula for c_\wp, the conductor of \Gamma_\wp, in terms of entries of the
Hamburger-Noether tableau of \wp.


title: Approximate vortex solution of Faddeev model

abstract:
  Through an Ansatz specifying the azimuthal-angle dependence of the solution,
the static field equation for vortex of the Faddeev model is converted to an
algebraic ordinary differential equation. An approximate analytic expression of
the vortex solution is explored so that the energy per unit vortex length
becomes as small as possible. It is observed that the minimum energy of vortex
is approximately proportional to the integer which specifies the solution.


title: Charmonium dissociation and recombination at RHIC and LHC

abstract:
  Charmonium production at heavy-ion colliders is considered within the
comovers interaction model. The formalism is extended by including possible
secondary J/psi production through recombination and an estimate of
recombination effects is made with no free parameters involved. The comovers
interaction model also includes a comprehensive treatment of initial-state
nuclear effects, which are discussed in the context of such high energies. With
these tools, the model properly describes the centrality and the rapidity
dependence of experimental data at RHIC energy, $\sqrt{s}$ = 200 GeV, for both
Au+Au and Cu+Cu collisions. Predictions for LHC, $\sqrt{s}$ = 5.5 TeV, are
presented and the assumptions and extrapolations involved are discussed.


title:
Comparing a Menagerie of Models for Estimating Molecular Divergence
  Times

abstract:
  Estimation of molecular evolutionary divergence times requires models of rate
change. These vary with regard to the assumption of what quantity is penalized.
The possibilities considered are the rate of evolution, the log of the rate of
evolution and the inverse of the rate of evolution. These models also vary with
regard to how time affects the expected variance of rate change. Here the
alternatives are not at all, linearly with time and as the product of rate and
time. This results in a set of nine models, both random walks and Brownian
motion. A priori any of these models could be correct, yet different
researchers may well prefer, or simply use, one rather than the others. Another
variable is whether to use a scaling factor to take account of the variance of
the process of rate change being unknown and therefore avoid minimizing the
penalty function with unrealistically large times. Here the difference these
models and assumptions make on a tree of mammals, with the root fixed and with
a single internal node fixed, is measured. The similarity of models is measured
as the correlation of their time estimates and visualized with a least squares
tree. The fit of model to data is measured and Q-Q plots are shown. Comparing
model estimates with each other, the age of clades within Laurasiatheria are
seen to vary far more across models than those within Supraprimates (informally
called Euarchontoglires). Especially problematic are the often-used fossil
calibrated nodes of horse/rhino and whale/hippo clashing with times within
Supraprimates and in particular no fossil rodent teeth older than ~60 mybp. A
scaling factor in addition to penalizing rate change is seen to yield
consistent relative time estimates irrespective of exactly where the
calibration point is placed.


title: Hyperboloidal foliations and scri-fixing

abstract:
  We discuss a gauge choice which allows us to avoid the introduction of
artificial timelike outer boundaries in numerical studies of test fields based
on a 3+1 decomposition of asymptotically flat background spacetimes. The main
idea is to include null infinity in the computational domain by conformally
compactifying the metric on hyperboloidal foliations and fixing the spatial
coordinate location of null infinity, i.e. scri-fixing. We construct such
coordinates explicitly on Minkowski, Schwarzschild and Kerr spacetimes.


title: Self-similar tiling systems, topological factors and stretching factors

abstract:
  In this paper we prove that if two self-similar tiling systems, with
respective stretching factors $\lambda_1$ and $\lambda_2$, have a common factor
which is a non periodic tiling system, then $\lambda_1$ and $\lambda_2$ are
multiplicatively dependent.


title:
The stability of spectroscopic instruments: A unified Allan variance
  computation scheme

abstract:
  The Allan variance is a standard technique to characterise the stability of
spectroscopic instruments used in astronomical observations. The period for
switching between source and reference measurement is often derived from the
Allan minimum time.
  We propose a new approach for the computation of the Allan variance of
spectrometer data combining the advantages of the two existing methods into a
unified scheme. Using the Allan variance spectrum we derive the optimum
strategy for symmetric observing schemes minimising the total uncertainty of
the data resulting from radiometric and drift noise.
  The unified Allan variance computation scheme is designed to trace
total-power and spectroscopic fluctuations within the same framework. The
method includes an explicit error estimate both for the individual Allan
variance spectra and for the derived stability time. A new definition of the
instrument stability time allows to characterise the instrument even in the
case of a fluctuation spectrum shallower than 1/f, as measured for the total
power fluctuations in high-electron-mobility transistors. We find a non-linear
impact of the binning of spectrometer channels on the resulting noise and the
Allan time deviating from the description in existing theoretical treatments.


title:
The von Neumann Hierarchy for Correlation Operators of Quantum
  Many-Particle Systems

abstract:
  The Cauchy problem for the von Neumann hierarchy of nonlinear equations is
investigated. One describes the evolution of all possible states of quantum
many-particle systems by the correlation operators. A solution of such
nonlinear equations is constructed in the form of an expansion over particle
clusters whose evolution is described by the corresponding order cumulant
(semi-invariant) of evolution operators for the von Neumann equations. For the
initial data from the space of sequences of trace class operators the existence
of a strong and a weak solution of the Cauchy problem is proved. We discuss the
relationships of this solution both with the $s$-particle statistical
operators, which are solutions of the BBGKY hierarchy, and with the
$s$-particle correlation operators of quantum systems.


title: Cobham-Semenov theorem and $\NN^d$-subshifts

abstract:
  We give a new proof of the Cobham's first theorem using ideas from symbolic
dynamics and of the Cobham-Semenov theorem (in the primitive case) using ideas
from tiling dynamics.


title: Fluctuating charge density waves in the Hubbard model

abstract:
  The charge susceptibility of the two-dimensional repulsive Hubbard model is
investigated using the diagram technique developed for the case of strong
correlations. In this technique, a power series in the hopping constant is
used. It is shown that once the Fermi level crosses one of the Hubbard subbands
a sharp peak appears in the momentum dependence of the static susceptibility.
With further departure from half-filling the peak transforms to a ridge around
the $\Gamma$ point. In the considered range $0\leq|1-\bar{n}|\alt 0.2$ of the
electron filling $\bar{n}$ the static susceptibility is finite which points to
the absence of the long-range charge ordering. However, for $|1-\bar{n}|\approx
0.12$ the susceptibility maxima are located halfway between the center and the
boundaries of the Brillouin zone. In this case an interaction of carriers with
tetragonal distortions can stabilize the charge density wave with the
wavelength of four lattice spacings, as observed experimentally in the
low-temperature tetragonal phase of lanthanum cuprates. In the range of
parameters inherent in cuprate perovskites the character of the susceptibility
evolution with $\bar{n}$ depends only weakly on the ratio of the
nearest-neighbor hopping constant to the Hubbard repulsion and on details of
the initial band structure. The location of the susceptibility maxima in the
Brillouin zone is mainly determined by the value of $\bar{n}$.


title: Global dynamical model of the cardiovascular system

abstract:
  Blood system functions are very diverse and important for most processes in
human organism. One of its primary functions is matter transport among
different parts of the organism including tissue supplying with oxygen, carbon
dioxide excretion, drug propagation etc. Forecasting of these processes under
normal conditions and in the presence of different pathologies like
atherosclerosis, loss of blood, anatomical abnormalities, pathological changing
in chemical transformations and others is significant issue for many
physiologists. In this connection should be pointed out that global processes
are of special interest as they include feedbacks and interdependences among
different regions of the organism. Thus the main goal of this work is to
develop the model allowing to describe effectively blood flow in the whole
organism. As we interested in global processes the models of the four vascular
trees (arterial and venous parts of systemic and pulmonary circulation) must be
closed with heart and peripheral circulation models. As one of the model
applications the processes of the blood loss is considered in the end of the
paper.


title:
Recent Progress in Special Colombeau Algebras: Geometry, Topology, and
  Algebra

abstract:
  Over the past few years there has been considerable progress in the
structural understanding of special Colombeau algebras. We present some of the
main trends in this development: non-smooth differential geometry, locally
convex theory of modules over the ring of generalized numbers, and algebraic
aspects of Colombeau theory. Some open problems are given and directions of
further research are outlined.


title: Finite Automata Based on Quantum Logic and Their Determinization

abstract:
  We give the quantum subset construction of orthomodular lattice-valued finite
automata, then we show the equivalence between orthomodular lattice-valued
finite automata, orthomodular lattice-valued deterministic finite automata and
orthomodular lattice-valued finite automata with empty string-moves. Based on
these equivalences, we study the algebraic operations on orthomodular
lattice-valued regular languages, then we establish Kleene theorem in the frame
of quantum logic.


title:
Numerical simulations of cardiovascular diseases and global matter
  transport

abstract:
  Numerical model of the peripheral circulation and dynamical model of the
large vessels and the heart are discussed in this paper. They combined together
into the global model of blood circulation. Some results of numerical
simulations concerning matter transport through the human organism and heart
diseases are represented in the end.


title:
Long-term Nonlinear Behaviour of the Magnetorotational Instability in a
  Localised Model of an Accretion Disc

abstract:
  For more than a decade, the so-called shearing box model has been used to
study the fundamental local dynamics of accretion discs. This approach has
proved to be very useful because it allows high resolution and long term
studies to be carried out, studies that would not be possible for a global
disc.
  Localised disc studies have largely focused on examining the rate of enhanced
transport of angular momentum, essentially a sum of the Reynolds and Maxwell
stresses. The dominant radial-azimuthal component of this stress tensor is, in
the classic Shakura-Sunayaev model, expressed as a constant alpha times the
pressure. Previous studies have estimated alpha based on a modest number of
orbital times. Here we use much longer baselines, and perform a cumulative
average for alpha. Great care must be exercised when trying to extract
numerical alpha values from simulations: dissipation scales, computational box
aspect ratio, and even numerical algorithms all affect the result. This study
suggests that estimating alpha becomes more, not less, difficult as
computational power increases.


title: Full perturbation solution for the flow in a rotated torus

abstract:
  We present a perturbation solution for a pressure-driven fluid flow in a
rotating toroidal channel. The analysis shows the difference between the
solutions of full and simplified equations studied earlier. The result is found
to be reliable for {\it low} Reynolds number ($\R$) as was the case for a
previously studied solution for high $\R$. The convergence conditions are
defined for the whole range of governing parameters. The viscous flow exhibits
some interesting features in flow pattern and hydrodynamic characteristics.


title: Lorentz-symmetry violating decays in a medium

abstract:
  Various decay processes, such as the decay of a spin-1 particle into two
photons or the gravitational decay of a spin-1/2 fermion, are forbidden in the
vacuum by a combination of requirements, including angular momentum
conservation, Lorentz invariance and gauge invariance. We show that such
processes can occur in a medium, such as a thermal background of particles,
even if it is homogeneous and isotropic. We carry out a model-independent
analysis of the vertex function for such processes in terms of a set of form
factors, and show that the amplitude can be non-zero while remaining consistent
with the symmetry principles mentioned above. The results simulate Lorentz
symmetry violating effects, although in this case they arise from completely
Lorentz-invariant physics.


title: Electronic properties of double-layer carbon nanotubes

abstract:
  The electronic spectra for double-wall zigzag and armchair nanotubes are
found. The influence of nanotube curvatures on the electronic spectra is also
calculated. Our finding that the outer shell is hole doped by the inner shell
is in the difference between Fermi levels of individual shells which originate
from the different hybridization of pi-orbital. The shift and rotation of the
inner nanotube with respect to the outer nanotube are investigated. We found
stable semimetal characteristics of the armchair DWNTs in regard of the shift
and rotation of the inner nanotube. We predict the shift of k_F towards the
bigger wave vectors with decreasing of the radius of the armchair nanotube.


title: Role of antikaon condensation in r-mode instability

abstract:
  We investigate the effect of antikaon condensed matter on bulk viscosity in
rotating neutron stars. We use relativistic field theoretical models to
construct the equation of state of neutron stars with the condensate, where the
phase transition from nucleonic to $K^-$ condensed phase is assumed to be of
first order. We calculate the coefficient of bulk viscosity due to the
non-leptonic weak interaction n --> p + K^-. The influence of antikaon bulk
viscosity on the gravitational radiation reaction driven instability in the
r-modes is investigated. We compare our results with the previously studied
non-leptonic weak interaction $n + p --> p + \Lambda$ involving hyperons on the
damping of the r-mode oscillations.
  We find that the bulk viscosity coefficient due to the non-leptonic weak
process involving the condensate is suppressed by several orders of magnitude
in comparison with the non-superfluid hyperon bulk viscosity coefficient.
Consequently, the antikaon bulk viscosity may not be able to damp the r-mode
instability, while hyperon bulk viscosity can effectively suppress r-mode
oscillations at low temperatures. Hence neutron stars containing $K^-$
condensate in their core could be possible sources of gravitational waves.


title:
Higher Dimensional Bondi Energy with a Globally Specified Background
  Structure

abstract:
  A higher (even spacetime) dimensional generalization of the Bondi energy has
recently been proposed by gr-qc/0304054 within the framework of conformal
infinity and Hamiltonian formalizm. The gauge condition employed in
gr-qc/0304054 to derive the Bondi energy expression is, however, peculiar in
the sense that cross-sections of null infinity specified by that gauge are
anisotropic and in fact non-compact. For this reason, that gauge is difficult
to use for explicit computations of the Bondi energy in general, asymptotically
flat radiative spacetimes. Also it is not clear, under that gauge condition,
whether apparent difference between the expressions of higher dimensional Bondi
energy and the 4-dimensional one is due to the choice of gauges or
qualitatively different nature of higher dimensional gravity from 4-dimensional
gravity. In this paper, we consider instead, Gaussian null conformal gauge as
one of more natural gauge conditions that admit a global specification of
background structure with compact, spherical cross-sections of null infinity.
Accordingly, we modify the previous definition of higher dimensional news
tensor so that it becomes well-defined in the Gaussian null conformal gauge and
derive, for vacuum solutions, the expression for the Bondi energy-momentum in
the new gauge choice, which takes a universal form in arbitrary (even
spacetime) dimensions greater than or equal to four.


title:
Entanglement propagation through spin chains in the presence of a
  staggered magnetic field

abstract:
  We study the dynamics of entanglement in the XY spin chain subject to a
staggered magnetic field and contrast it to the previously studied uniform
field case. We find that, depending on parameter values, a staggered field can
provide better conditions for a perfect entanglement transfer, while even a
modest amount of exchange anisotropy appears to have a strong detrimental
effect. We also study interactions between different waves of entanglement and
assess the possibility of simultaneous transmission of multiple bits of quantum
information.


title: Publication and citation statistics for UK astronomers

abstract:
  This article presents a survey of publication and citation statistics for 835
UK professional astronomers: the majority of academics and contract researchers
within the UK astronomical community. I provide histograms of these
bibliometrics for the whole sample as well as of the median values for the
individual departments. I discuss the distribution of top bibliometric
performers in the sample, and make some remarks on the usage of bibliometrics
in a real-world assessment exercise.


title: Diffusion of muonium and hydrogen in diamond

abstract:
  Jump rates of muonium and hydrogen in diamond are calculated by quantum
transition-state theory, based on the path-integral centroid formalism. This
technique allows us to study the influence of vibrational mode quantization on
the effective free-energy barriers Delta F for impurity diffusion, which are
renormalized respect to the zero-temperature classical calculation. For the
transition from a tetrahedral (T) site to a bond-center (BC) position, Delta F
is larger for hydrogen than for muonium, and the opposite happens for the
transition from BC to T. The calculated effective barriers decrease for rising
temperature, except for the muonium transition from T to BC sites. Calculated
jump rates are in good agreement to available muon spin rotation data.


title: Sunyaev-Zeldovich and Cosmic Microwave Background

abstract:
  Since its original formulation the Sunyaev-Zeldovich (SZ) effect has been
recognized as a ``powerful laboratory'' for our comprehension of physical
processes in cosmic structures and to derive crucial information on some
general properties of the universe. After a discussion of the fundamental
concepts and of some well established applications of the SZ effect towards
galaxy clusters, I will focus on dedicated themes related to the SZ effect and
other features in the cosmic microwave background (CMB) of particular interest
in the view of the extremely high angular resolution observations achievable in
the future with the Square Kilometre Array (SKA). SKA will allow the mapping of
the thermal and density structure of clusters of galaxies at radio and
centimetre bands with unprecedented resolution and sensitivity and with an
extremely accurate control of extragalactic radio source contamination. The
signatures from SZ effects and free-free emission at galactic scales and in the
intergalactic medium probe the structure evolution at various cosmic times. The
detection of these sources and their imaging at the high resolution and
sensitivity achievable with SKA will greatly contribute to the comprehension of
crucial cosmological and astrophysical aspects, as the physical conditions of
early ionized halos, quasars and proto-galactic gas. The spectacular
improvement in our understanding of the properties of extragalactic radio
sources at very faint fluxes achievable with SKA will allow to accurately model
their contribution to the diffuse radio background, greatly contributing to the
interpretation of next generation of CMB spectrum experiments devoted to probe
the thermal plasma history at early times.


title: Boundary conditions: The path integral approach

abstract:
  The path integral approach to quantum mechanics requires a substantial
generalisation to describe the dynamics of systems confined to bounded domains.
Non-local boundary conditions can be introduced in Feynman's approach by means
of boundary amplitude distributions and complex phases to describe the quantum
dynamics in terms of the classical trajectories. The different prescriptions
involve only trajectories reaching the boundary and correspond to different
choices of boundary conditions of selfadjoint extensions of the Hamiltonian.
One dimensional particle dynamics is analysed in detail.


title: Investigation of Lattice QCD with Wilson fermions with Gaussian Smearing

abstract:
  We present a detailed study of pion and rho mass, decay constants and quark
mass in Lattice QCD with two flavors of dynamical quarks. We use Wilson gauge
and fermion action at $\beta=5.6$ on $ 16^3 \times 32 $ lattice at eight values
of the Wilson hopping parameter in the range 0.156 - 0.158. We perform a
detailed investigation of the effect of gaussian smearing on both source and
sink. We determine the optimum smearing parameter for various correlators for
each value of the Wilson hopping parameter. The effects of smearing on
observables are compared with those measured using local operators. We also
investigate systematic effects in the extraction of masses and decay constants
using different types of correlation functions for pion observables. We make
interesting observations regarding chiral extrapolations and finite volume
effects of different operators.


title: Interplay between Yukawa and Tomonaga in the Birth of Mesons

abstract:
  Light is shed on the early stage in the birth of Yukawa's meson theory,
particularly on the interplay between Yukawa and Tomonaga in 1933. The
discovery of the muon by Nishina' group in 1937 is also reviewed. It is pointed
out that Heisenberg's attempt to explain the nuclear force in terms of the
Heitler-London scheme, overcome by Yukawa and abandoned since then, is now
being revived as a mechanism for a super strong nuclear force caused by a
migrating real Kbar meson.


title: An optimal boundedness on weak $\bQ$-Fano threefolds

abstract:
  Let $X$ be a terminal weak $\bQ$-Fano threefold. We prove that $P_{-6}(X)>0$
and $P_{-8}(X)>1$. We also prove that the anti-canonical volume has a universal
lower bound $-K_X^3 \geq 1/330$. This lower bound is optimal.


title: Convolution type stochastic Volterra equations

abstract:
  The aim of this work is to present, in self-contained form, results
concerning fundamental and the most important questions related to linear
stochastic Volterra equations of convolution type. The paper is devoted to
study the existence and some kind of regularity of solutions to stochastic
Volterra equations in Hilbert space and the space of tempered distributions, as
well.
  In recent years the theory of Volterra equations, particularly fractional
ones, has undergone a big development. This is an emerging area of research
with interesting mathematical questions and various important applications. The
increasing interest in these equations comes from their applications to
problems from physics and engeenering, particularly from viscoelasticity, heat
conduction in materials with memory or electrodynamics with memory.


title: Limit Theorems for Internal Aggregation Models

abstract:
  We study the scaling limits of three different aggregation models on the
integer lattice Z^d: internal DLA, in which particles perform random walks
until reaching an unoccupied site; the rotor-router model, in which particles
perform deterministic analogues of random walks; and the divisible sandpile, in
which each site distributes its excess mass equally among its neighbors. As the
lattice spacing tends to zero, all three models are found to have the same
scaling limit, which we describe as the solution to a certain PDE free boundary
problem in R^d. In particular, internal DLA has a deterministic scaling limit.
We find that the scaling limits are quadrature domains, which have arisen
independently in many fields such as potential theory and fluid dynamics. Our
results apply both to the case of multiple point sources and to the
Diaconis-Fulton smash sum of domains. In the special case when all particles
start at a single site, we show that the scaling limit is a Euclidean ball in
R^d, and give quantitative bounds on the rate of convergence to a ball. We also
improve on the previously best known bounds of Le Borgne and Rossin in Z^2 and
Fey and Redig in higher dimensions for the shape of the classical abelian
sandpile model. Lastly, we study the sandpile group of a regular tree whose
leaves are collapsed to a single sink vertex, and determine the decomposition
of the full sandpile group as a product of cyclic groups. For the regular
ternary tree of height n, for example, the sandpile group is isomorphic to
(Z_3)^{2^{n-3}} x (Z_7)^{2^{n-4}} x ... x Z_{2^{n-1}-1} x Z_{2^n-1}. We use
this result to prove that rotor-router aggregation on the regular tree yields a
perfect ball.


title:
Bochner transforms, perturbations and amoebae of holomorphic almost
  periodic mappings in tube domains

abstract:
  We give an alternative representation of the closure of the Bochner transform
of a holomorphic almost periodic mapping in a tube domain. For such mappings we
introduce a new notion of amoeba and we show that, for mappings which are
regular in the sense of Ronkin, this new notion agrees with Favorov's one. We
prove that the amoeba complement of a regular holomorphic almost periodic
mapping, defined on Cn and taking its values in Cm+1, is a Henriques m-convex
subset of Rn. Finally, we compare some different notions of regularity.


title: Factorization (Splitting)

abstract:
  We show some elementary facts about the semantical analogue of Parikh's
Splitting, which we call Factorization.


title:
Entropy-driven phase transition in a system of long rods on a square
  lattice

abstract:
  The isotropic-nematic (I-N) phase transition in a system of long straight
rigid rods of length k on square lattices is studied by combining Monte Carlo
simulations and theoretical analysis. The process is analyzed by comparing the
configurational entropy of the system with the corresponding to a fully aligned
system, whose calculation reduces to the 1D case. The results obtained (1)
allow to estimate the minimum value of k which leads to the formation of a
nematic phase and provide an interesting interpretation of this critical value;
(2) provide numerical evidence on the existence of a second phase transition
(from a nematic to a non-nematic state) occurring at density close to 1 and (3)
allow to test the predictions of the main theoretical models developed to treat
the polymers adsorption problem.


title: Similarity, Codepth Two Bicomodules and QF Bimodules

abstract:
  For any k-coalgebra C it is shown that similar quasi-finite C-comodules have
strongly equivalent coendomorphism coalgebras;
  (the converse is in general not true). As an application we give a general
result about codepth two coalgebra homomorphisms. Also a notion of codepth two
bicomodule is introduced. The last section applies similarity to an
endomorphism ring theorem for quasi-Frobenius (QF) bimodules and then to finite
depth ring extensions. For QF extensions, we establish that left and right
depth two are equivalent notions as well as a converse endomorphism theorem,
and characterize depth three in terms of separability and depth two.


title:
Applications of distance between probability distributions to
  gravitational wave data analysis

abstract:
  We present a definition of the distance between probability distributions.
Our definition is based on the $L_1$ norm on space of probability measures. We
compare our distance with the well-known Kullback-Leibler divergence and with
the proper distance defined using the Fisher matrix as a metric on the
parameter space. We consider using our notion of distance in several problems
in gravitational wave data analysis: to place templates in the parameter space
in searches for gravitational-wave signals, to assess quality of search
templates, and to study the signal resolution.


title: Opinion Dynamics with Hopfield Neural Networks

abstract:
  In Hopfield neural networks with up to 10^8 nodes we store two patterns
through Hebb couplings. Then we start with a third random pattern which is
supposed to evolve into one of the two stored patterns, simulating the
cognitive process of associative memory leading to one of two possible
opinions. With probability p each neuron independently, instead of following
the Hopfield rule, takes over the corresponding value of another network, thus
simulating how different people can convince each other. A consensus is
achieved for high p.


title: Motions of electrons in adiabatically perturbed periodic structures

abstract:
  We study the motion of electrons in a periodic background potential (usually
resulting from a crystalline solid). For small velocities one would use either
the non-magnetic or the magnetic Bloch hamiltonian, while in the relativistic
regime one would use the Dirac equation with a periodic potential. The
dynamics, with the background potential included, is perturbed either through
slowly varying external electromagnetic potentials or through a slow
deformation of the crystal. In either case we discuss how the Hilbert space of
states decouples into almost invariant subspaces and explain the effective
dynamics within such a subspace.


title: Matrix Model Maps and Reconstruction of AdS SUGRA Interactions

abstract:
  We consider the question of reconstructing (cubic) SUGRA interactions in
AdS/CFT. The method we introduce is based on the matrix model maps (MMP) which
were previously successfully employed at the linearized level. The strategy is
to start with the map for 1/2 BPS configurations which is exactly known (to all
orders) in the hamiltonian framework. We then use the extension of the matrix
model map with the corresponding Ward identities to completely specify the
interaction. A central point in this construction is the non-vanishing of
off-shell interactions (even for highest-weight states).


title:
Deuteron production in p-Be interactions at 450 GeV/c and the coalescing
  model

abstract:
  The analysis of the deuteron production in p--Be interactions at 450 GeV/c
taken by the NA56/SPY experiment at CERN SPS is presented. In the framework of
the coalescence model, the coalescence factor $\kappa$ is determined as $(0.79
\pm 0.05 \pm 0.13) \times 10^{-2}$. Our results disfavour the hypothesis that
coalescence be the dominant mechanism for deuteron production in $p+Be$
interactions at low $p_T$.


title:
Statistical relativistic temperature transformation for ideal gas of
  bradyons, luxons and tachyons

abstract:
  Starting from a microcanonical statistical approach and special relativity,
the relativistic transformations for temperature and pressure for an ideal gas
of bradyons, luxons or tachyons is found. These transformations are in
agreement with the three laws of thermodynamic and our temperature
transformation is the same as Ott's. Besides, it is shown that the
thermodynamic $dS$ element is Lorentz-invariant.


title: The time-dependent Born-Oppenheimer approximation

abstract:
  We explain why the conventional argument for deriving the time-dependent
Born-Oppenheimer approximation is incomplete and review recent mathematical
results, which clarify the situation and at the same time provide a systematic
scheme for higher order corrections. We also present a new elementary
derivation of the correct second-order time-dependent Born-Oppenheimer
approximation and discuss as applications the dynamics near a conical
intersection of potential surfaces and reactive scattering.


title: The design of the time-of-flight system for MICE

abstract:
  The international Muon Ionization Cooling Experiment (MICE) will carry out a
systematic investigation of ionization cooling of a muon beam. As the emittance
measurement will be done on a particle-by-particle basis, a sophisticated beam
instrumentation is needed to measure particle coordinates and timing vs RF. The
MICE time-of-flight system will measure timings with a resolution better than
70 ps per plane, in a harsh environment due to high particle rates, fringe
magnetic fields and electron backgrounds from RF dark noise.


title: The Partition Function of a Multi-Component Coulomb Gas on a Circle

abstract:
  We study a two-dimensional Coulomb gas consisting of a mixture of particles
carrying various positive multiple integer charges, confined on a unit circle.
We consider the system in the canonical and grand canonical ensembles, and
attempt to calculate the partition functions analytically, using Toeplitz and
confluent Vandermonde determinants. Just like in the simple one-component
system (Dyson gas), the partition functions simplify at special temperature
$\beta=2$, allowing us to find compact expressions for them.

categories: cond-mat.stat-mech hep-th math-ph math.MP


title:
Source breakup dynamics in Au+Au Collisions at sqrt(s_NN)=200 GeV via
  three-dimensional two-pion source imaging

abstract:
  A three-dimensional (3D) correlation function obtained from mid-rapidity, low
pT pion pairs in central Au+Au collisions at sqrt(s_NN)=200 GeV is studied. The
extracted model-independent source function indicates a long range tail in the
directions of the pion pair transverse momentum (out) and the beam (long).
Model comparisons to these distensions indicate a proper breakup time \tau_0 ~
9 fm/c and a mean proper emission duration \Delta\tau ~ 2 fm/c, leading to
sizable emission time differences
  (<|\Delta \tau_LCM |> ~ 12 fm/c), partly due to resonance decays.
  They also suggest an outside-in "burning" of the emission source reminiscent
of many hydrodynamical models.


title: New reductions of integrable matrix PDEs: $Sp(m)$-invariant systems

abstract:
  We propose a new type of reduction for integrable systems of coupled matrix
PDEs; this reduction equates one matrix variable with the transposition of
another multiplied by an antisymmetric constant matrix. Via this reduction, we
obtain a new integrable system of coupled derivative mKdV equations and a new
integrable variant of the massive Thirring model, in addition to the already
known systems. We also discuss integrable semi-discretizations of the obtained
systems and present new soliton solutions to both continuous and semi-discrete
systems. As a by-product, a new integrable semi-discretization of the Manakov
model (self-focusing vector NLS equation) is obtained.


title:
Analytical study of the plasmonic modes of metal nanoparticle circular
  array

abstract:
  We analyze the plasmonic modes of a metal nanoparticle circular array. Closed
form solutions to the eigenmode problem are given. For each polarization, the
plasmonic mode with the highest quality is found to be an antiphase mode. We
found that the significant suppression in radiative loss can be understood as
the cancellation of the dipolar radiation term in the radiative linewidth. The
remaining finite radiative linewidth decreases exponentially as the number of
particle increases.


title:
Positive Energy Representations, Holomorphic Discrete Series and
  Finite-Dimensional Irreps

abstract:
  Let G be a semi-simple non-compact Lie group with unitary lowest/highest
weight representations. We consider explicitly the relation between three types
of representations of G: positive energy (unitary lowest
weight)representations, (holomorphic) discrete series representations and
non-unitary finite-dimensional irreps. We consider mainly the conformal groups
SO(n,2) treating in full detail the cases n=1,3,4.


title:
Study on $N\bar{N}$ $S$-wave Elastic Cross Section and Possible Bound
  States Within a Constituent Quark Model

abstract:
  In the framework of a chiral constituent quark model, considering the
contributions of $\pi$ annihilation and one-gluon annihilation, the
proton-antiproton $S$-wave elastic scattering cross section experimental data
can be reproduced by adjusting properly one-gluon annihilation coupling
constant. Meanwhile, using the fixed model parameter, we do a dynamical
calculation for all possible $S$-wave nucleon-antinucleon states, the results
show that, there is no $S$-wave bound state as indicated by a strong
enhancement at threshold of $p\bar{p}$ in $J/\psi$ and $B$ decays.


title: Quantum Kolmogorov Complexity and the Quantum Turing Machine

abstract:
  The purpose of this thesis is to give a formal definition of quantum
Kolmogorov complexity (QC), and rigorous mathematical proofs of its basic
properties. The definition used here is similar to that by Berthiaume, van Dam,
and Laplante. It defines the QC of some indeterminate-length qubit string \rho
as the minimum base length of any quantum input which makes a quantum Turing
machine (QTM) halt and output \rho, up to some error tolerance.
  First, we prove that there is a QTM which is universal in the sense of input
base length. Furthermore, we show several general properties of QTMs, including
a result on mutually orthogonal ``halting spaces'', and a way to transform
every almost-halting input into a deterministically-halting input by adding at
most a constant number of qubits.
  Afterwards, we apply these results to QC. In particular, we show that QC is
invariant, incompressible, agrees with classical Kolmogorov complexity for
classical strings, and is closely related to von Neumann entropy for ergodic
quantum information sources.


title: Temperature dependence of surface magnetization in local-moment systems

abstract:
  We present a theory to study the temperature-dependent behavior of surface
states in a ferromagnetic semi-infinite crystal. Our approach is based on the
single-site approximation for the \emph{s-f} model. The effect of the
semi-infinite nature of the crystal is taken into account by a localized
perturbation method. Using the mean-field theory for the layer-dependent
magnetization, the local density of states and the electron-spin polarization
are investigated at different temperatures for ordinary and surface transition
cases. The results show that the surface magnetic properties may differ
strongly from those in the bulk and the coupling constant of atoms plays a
decisive role in the degree of spin polarization. In particular, for the case
in which the exchange coupling constant on the surface and between atoms in the
first and second layer is higher than the corresponding in the bulk, an
enhancement of surface Curie temperature and hence the spin polarization can be
obtained.


title: A Note on Overtwisted Contact Structures

abstract:
  In this note, we use the recent work of Honda-Kazez-Matic [HKM] to prove that
a closed contact 3-manifold admitting a compatible open book decomposition with
a nontrivial monodromy which can be presented as a product of left handed Dehn
twists is overtwisted.


title:
Bounds on the fine structure constant variability from FeII absorption
  lines in QSO spectra

abstract:
  The Single Ion Differential alpha Measurement (SIDAM) method for measuring
fine stucture variations (daa)and its figures of merit are illustrated together
with the results produced by means of FeII absorption lines of QSO intervening
systems. The method provides daa ~= -0.12(+/- 1.79) ppm (parts-per-million) at
zabs = 1.15 towards HE 0515--4414 and daa = 5.66(+/-2.67) ppm at zabs= 1.84
towards Q 1101--264, which are so far the most accurate measurements for single
systems. SIDAM analysis for 3 systems from the Chand et al. (2004) sample
provides inconsistent results which we interpret as due to calibration errors
of the Chand et al. data at the level of about 10 ppm. In one system evidence
for photo-ionization Doppler shift between MgII and FeII lines is found. This
evidence has important bearings on the Many Multiplet method where the signal
for daa variability is carried mainly by systems involving MgII absorbers. Some
correlations are also found in the Murphy et al. sample which suggest larger
errors than previously reported. Thus, we consider unlikely that both the Chand
et al. and Murphy et al. datasets could provide an estimate of daa with an
accuracy at the level of 1 ppm. A new spectrograph like the ESPRESSO project
will be crucial to make progress in the astronomical determination of daa.


title:
Efficient representation as a design principle for neural coding and
  computation

abstract:
  Does the brain construct an efficient representation of the sensory world? We
review progress on this question, focusing on a series of experiments in the
last decade which use fly vision as a model system in which theory and
experiment can confront each other. Although the idea of efficient
representation has been productive, clearly it is incomplete since it doesn't
tell us which bits of sensory information are most valuable to the organism. We
suggest that an organism which maximizes the (biologically meaningful) adaptive
value of its actions given fixed resources should have internal representations
of the outside world that are optimal in a very specific information theoretic
sense: they maximize the information about the future of sensory inputs at a
fixed value of the information about their past. This principle contains as
special cases computations which the brain seems to carry out, and it should be
possible to test this optimization directly. We return to the fly visual system
and report the results of preliminary experiments that are in encouraging
agreement with theory.


title: Information and fitness

abstract:
  The growth rate of organisms depends both on external conditions and on
internal states, such as the expression levels of various genes. We show that
to achieve a criterion mean growth rate over an ensemble of conditions, the
internal variables must carry a minimum number of bits of information about
those conditions. Evolutionary competition thus can select for cellular
mechanisms that are more efficient in an abstract, information theoretic sense.
Estimates based on recent experiments suggest that the minimum information
required for reasonable growth rates is close to the maximum information that
can be conveyed through biologically realistic regulatory mechanisms. These
ideas are applicable most directly to unicellular organisms, but there are
analogies to problems in higher organisms, and we suggest new experiments for
both cases.


title: Structure of strange baryons

abstract:
  The charge radii and quadrupole moments of baryons with nonzero strangeness
are calculated using a parametrization method based on the symmetries of the
strong interaction.


title:
Quasielastic axial-vector mass from experiments on neutrino-nucleus
  scattering

abstract:
  We analyze available experimental data on the total and differential
charged-current cross sections for quasielastic neutrino and antineutrino
scattering off nucleons, measured with a variety of nuclear targets in the
accelerator experiments at ANL, BNL, FNAL, CERN, and IHEP, dating from the end
of sixties to the present day. The data are used to adjust the poorly known
value of the axial-vector mass of the nucleon.


title: Cell biology: Networks, regulation, pathways

abstract:
  This review was written for the Encyclopedia of Complexity and System Science
(Springer-Verlag, Berlin, 2008), and is intended as a guide to the growing
literature which approaches the phenomena of cell biology from a more
theoretical point of view. We begin with the building blocks of cellular
networks, and proceed toward the different classes of models being explored,
finally discussing the "design principles" which have been suggested for these
systems. Although largely a dispassionate review, we do draw attention to areas
where there seems to be general consensus on ideas that have not been tested
very thoroughly and, more optimistically, to areas where we feel promising
ideas deserve to be more fully explored.


title: Neutrinos from a core collapse supernova

abstract:
  The neutrino burst from a galactic supernova can help determine the neutrino
mass hierarchy and $\theta_{13}$, and provide crucial information about
supernova astrophysics. Here we review our current understanding of the
neutrino burst, flavor conversions of these neutrinos, and model independent
signatures of various neutrino mixing scenarios.


title: Dehn surgeries that yield fibred $3$--manifolds

abstract:
  We study Dehn surgeries on null-homotopic knots that yield fibred
$3$--manifolds when an additional (but natural) homological restriction is
imposed. The major tool used is Gabai's theory of sutured manifold
decomposition. Such surgeries are negative examples to a question of Michel
Boileau. Another result we will prove is about surgeries which reduce the
Thurston norm of a fibred manifold.


title:
The integral Chow ring of the stack of hyperelliptic curves of even
  genus

abstract:
  Let $g$ be an even positive integer. In this paper we compute the integral
Chow ring of the stack of smooth hyperelliptic curves of genus $g$.


title: Precision Measurement of a Particle Mass at the Linear Collider

abstract:
  Precision measurement of the stop mass at the ILC is done in a method based
on cross-sections measurements at two different center-of-mass energies. This
allows to minimize both the statistical and systematic errors. In the framework
of the MSSM, a light stop, compatible with electro-weak baryogenesis, is
studied in its decay into a charm jet and neutralino, the Lightest
Supersymmetric Particle(LSP), as a candidate of dark matter. This takes place
for a small stop-neutralino mass difference.


title:
Science with a 16m VLT: the case for variability of fundamental constan
  ts

abstract:
  Only astronomical observations can effectively probe in space-time the
variabil ity of the physical dimensionless constants such as the fine structure
constant and proton-to-electron mass ratio, \mu, which are related to fund
amental forces of nature. Several theories beyond the Standard Model (SM) allow
fundamental constants to vary, but they cannot make quantitative predictions so
that only laboratory experiments and astronomical observations can show if th
is is the case or set the allowed bounds. At the moment of writing there are c
laims for a variability of both \alpha and \mu at 5 and 4\sigma of C.L.,
respectively, although for \alpha they are contrasted by null results. The
observations are challenging and a new spectrograph such as ESPRESSO at the
combined incoherent focus of 4 VLT units (a potential 16 m equivalent
telescope) will allow for a significant improvement in the precision
measurement clearing up the controversy. If the variations will be confirmed,
the implications are far reaching, revealing new physics beyond the SM and
pointing a direction for GUTs theories. A most exciting ossibility is that a
variation of \alpha is induced by quintessence through its coupling with the
electromagnetic field. If this is the case an accurate measurement of the
variability could provide a way for reconstructing the equation of state of
Dark Energy (Avelino et al 2006).


title: The formation of spiral arms and rings in barred galaxies

abstract:
  We propose a new theory to explain the formation of spiral arms and of all
types of outer rings in barred galaxies. We have extended and applied the
technique used in celestial mechanics to compute transfer orbits. Thus, our
theory is based on the chaotic orbital motion driven by the invariant manifolds
associated to the periodic orbits around the hyperbolic equilibrium points. In
particular, spiral arms and outer rings are related to the presence of
heteroclinic or homoclinic orbits. Thus, R1 rings are associated to the
presence of heteroclinic orbits, while R1R2 rings are associated to the
presence of homoclinic orbits. Spiral arms and R2 rings, however, appear when
there exist neither heteroclinic nor homoclinic orbits. We examine the
parameter space of three realistic, yet simple, barred galaxy models and
discuss the formation of the different morphologies according to the properties
of the galaxy model. The different morphologies arise from differences in the
dynamical parameters of the galaxy.


title: Vacuum Structure and Boundary Renormalization Group

abstract:
  The vacuum structure is probed by boundary conditions. The behaviour of
thermodynamical quantities like free energy, boundary entropy and entanglement
entropy under the boundary renormalization group flow are analysed in 2D
conformal field theories. The results show that whereas vacuum energy and
boundary entropy turn out to be very sensitive to boundary conditions, the
vacuum entanglement entropy is independent of boundary properties when the
boundary of the entanglement domain does not overlap the boundary of the
physical space. In all cases the second law of thermodynamics holds along the
boundary renormalization group flow.


title: Constraints on Torsion from Lorentz Violation

abstract:
  Exceptional sensitivity to spacetime torsion can be achieved by searching for
its couplings to fermions. Recent experimental searches for Lorentz violation
are exploited to extract new constraints involving 19 of the 24 independent
torsion components down to levels of order 10^{-31} GeV.


title: Real and imaginary-time $Q\bar{Q}$ correlators in a thermal medium

abstract:
  We investigate the behavior of a pair of heavy fermions, denoted by $Q$ and
$\bar{Q}$, in a hot/dense medium. Although we have in mind the situation where
$Q$ and $\bar{Q}$ denote heavy quarks, our treatment will be limited to
simplified models, which bear only some general similarities with QCD. We study
in particular the limiting case where the mass of the heavy fermions is
infinite. Then a number of results can be derived exactly: a Schr\"odinger
equation can be established for the correlator of the heavy quarks; the
interaction effects exponentiate, leading to a simple instantaneous effective
potential for this Schr\"odinger equation. We consider simple models for the
medium in which the $Q\bar Q$ pair propagates. In the case where the medium is
a plasma of photons and light charged fermions, an imaginary part develops in
this effective potential. We discuss the physical interpretation of this
imaginary part in terms of the collisions between the heavy particles and the
light fermions of the medium; the same collisions also determine the damping
rate of the heavy fermions. Finally we study the connection between the
real-time propagator of the heavy fermion pair and its Euclidean counterpart,
and show that the real part of the potential entering the Schr\"odinger
equation for the real-time propagator is the free energy calculated in the
imaginary-time formalism.


title: Goresky-MacPherson calculus for the affine flag varieties

abstract:
  We use the fixed point arrangement technique developed by Goresky-MacPherson
to calculate the part of the equivariant cohomology of the affine flag
varieties generated by degree 2. This turns out to be a quadric cone. We also
describe the spectrum of the full equivariant cohomology ring as an explicit
geometric object. We use our results to show that the vertices of the moment
map images of the affine flag varieties lie on a paraboloid.


title:
On Harrell-Stubbe Type Inequalities for the Discrete Spectrum of a
  Self-Adjoint Operator

abstract:
  We produce a new proof and extend results by Harrell and Stubbe for the
discrete spectrum of a self-adjoint operator. An abstract approach--based on
commutator algebra, the Rayleigh-Ritz principle, and an ``optimal'' usage of
the Cauchy-Schwarz inequality--is used to produce ``parameter-free'',
``projection-free'' versions of their theorems. We also analyze the strength of
the various inequalities that ensue. The results contain classical bounds for
the eigenvalues. Extensions of a variety of inequalities \`a la Harrell-Stubbe
are illustrated for both geometric and physical problems.


title: Rediscovering the power of pairwise interactions

abstract:
  Two recent streams of work suggest that pairwise interactions may be
sufficient to capture the complexity of biological systems ranging from protein
structure to networks of neurons. In one approach, possible amino acid
sequences in a family of proteins are generated by Monte Carlo annealing of a
"Hamiltonian" that forces pairwise correlations among amino acid substitutions
to be close to the observed correlations. In the other approach, the observed
correlations among pairs of neurons are used to construct a maximum entropy
model for the states of the network as a whole. We show that, in certain
limits, these two approaches are mathematically equivalent, and we comment on
open problems suggested by this framework


title:
Island formation in disordered superconducting thin films at finite
  magnetic fields

abstract:
  The existence of "superconducting islands" (i.e., locally confined regions
with superconducting correlations) in amorphous superconducting thin films can
account for numerous experimental findings. Such spatial fluctuations in the
superconducting gap were indeed observed experimentally, and were shown to
persist into the insulating side of the superconductor-insulator transition. In
this work a detailed account on the formation and evolution of superconducting
islands in disordered two-dimensional superconductors is presented, using a
locally self-consistent numerical solution of the Bogoliubov-de-Gennes
equations. Specifically, the formation of SC islands is demonstrated, and their
evolution with an applied perpendicular magnetic field is studied in details,
along with the disorder-induced vortex-pinning. Simulating the presence of a
parallel Zeeman field it is demonstrated that the islands are indeed
uncorrelated superconducting domains. Experimental predictions based on this
analysis are presented.


title:
The inverse problem for representation functions for general linear
  forms

abstract:
  The inverse problem for representation functions takes as input a triple
(X,f,L), where X is a countable semigroup, f : X --> N_0 \cup {\infty} a
function, L : a_1 x_1 + ... + a_h x_h an X-linear form and asks for a subset A
\subseteq X such that there are f(x) solutions (counted appropriately) to
L(x_1,...,x_h) = x for every x \in X, or a proof that no such subset exists.
  This paper represents the first systematic study of this problem for
arbitrary linear forms when X = Z, the setting which in many respects is the
most natural one. Having first settled on the "right" way to count
representations, we prove that every primitive form has a unique representation
basis, i.e.: a set A which represents the function f \equiv 1. We also prove
that a partition regular form (i.e.: one for which no non-empty subset of the
coefficients sums to zero) represents any function f for which {f^{-1}(0)} has
zero asymptotic density. These two results answer questions recently posed by
Nathanson.
  The inverse problem for partition irregular forms seems to be more
complicated. The simplest example of such a form is x_1 - x_2, and for this
form we provide some partial results. Several remaining open problems are
discussed.


title: Geometric structure-preserving optimal control of the rigid body

abstract:
  In this paper we study a discrete variational optimal control problem for the
rigid body. The cost to be minimized is the external torque applied to move the
rigid body from an initial condition to a pre-specified terminal condition.
Instead of discretizing the equations of motion, we use the discrete equations
obtained from the discrete Lagrange--d'Alembert principle, a process that
better approximates the equations of motion. Within the discrete-time setting,
these two approaches are not equivalent in general. The kinematics are
discretized using a natural Lie-algebraic formulation that guarantees that the
flow remains on the Lie group SO(3) and its algebra so(3). We use Lagrange's
method for constrained problems in the calculus of variations to derive the
discrete-time necessary conditions. We give a numerical example for a
three-dimensional rigid body maneuver.


title: Creutz Fermions on an Orthogonal Lattice

abstract:
  In a recent paper, Creutz has given a new action describing two species of
Dirac fermions with exact chiral symmetry on the lattice. This action depends
on a parameter which may be fixed at a certain value in order to get the right
continuum limit. In this letter, we elaborate more on this idea and present an
action which is free of any other parameter except the fermion mass.


title: Judgment

abstract:
  The concept of a judgment as a logical action which introduces new
information into a deductive system is examined. This leads to a way of
mathematically representing implication which is distinct from the familiar
material implication, according to which "If A then B" is considered to be
equivalent to "B or not-A". This leads, in turn, to a resolution of the paradox
of the raven.


title:
Localization-Entropy from Holography on Null-Surfaces and the Split
  Property

abstract:
  Using the conformal equivalence of translational KMS states on chiral
theories with dilational KMS states obtained from restricting the vacuum state
to an interval (the chiral inversion of the Unruh-effect) it was shown in a
previous publications that the diverging volume (length) factor of the
thermodynamic limit corresponds to the logarithmic increase in the attenuation
length of the localization-caused vacuum polarization cloud near the causal
boundary. This is not a coincidence but rather a structural consequence of the
fact that both operator algebras are of the same unique von Neumann type which
is completely different from that met in quantum mechanical algebras. Together
with the technique of holographic projection this leads to the universal area
proportionality. The main aim in this paper is to present a derivation which is
more in the spirit of recent work on entanglement entropy in condensed matter
physics, especially to that of the replica trick as used by Cardy and
collaborators. The essential new ingredient is the use of the split property
which already has shown its constructive power in securing the existence of
models of factorizing theories.


title: On Normal Modes of a Warped Throat

abstract:
  As shown in arXiv:hep-th/0405282, the warped deformed conifold has two
bosonic massless modes, a pseudoscalar and a scalar, that are dual to the phase
and the modulus of the baryonic condensates in the cascading gauge theory. We
reconsider the scalar mode sector, mixing fluctuations of the NS-NS 2-form and
the metric, and include non-zero 4-d momentum $k_\mu$. The resulting pair of
coupled equations produce a discrete spectrum of $m_4^2=- k_\mu^2$ which is
interpreted as the spectrum of $J^{PC}= 0^{+-}$ glueballs in the gauge theory.
Similarly, we derive the spectrum of certain pseudoscalar glueballs with
$J^{PC}= 0^{--}$, which originate from the decoupled fluctuations of the RR
2-form. We argue that each of the massive scalar or pseudoscalar modes we find
belongs to a 4-d massive axial vector or vector supermultiplet. We also discuss
our results in the context of a finite length throat embedded into a type IIB
flux compactification.


title:
Regularization of fields for self-force problems in curved spacetime:
  foundations and a time-domain application

abstract:
  We propose an approach for the calculation of self-forces, energy fluxes and
waveforms arising from moving point charges in curved spacetimes. As opposed to
mode-sum schemes that regularize the self-force derived from the singular
retarded field, this approach regularizes the retarded field itself. The
singular part of the retarded field is first analytically identified and
removed, yielding a finite, differentiable remainder from which the self-force
is easily calculated. This regular remainder solves a wave equation which
enjoys the benefit of having a non-singular source. Solving this wave equation
for the remainder completely avoids the calculation of the singular retarded
field along with the attendant difficulties associated with numerically
modeling a delta function source. From this differentiable remainder one may
compute the self-force, the energy flux, and also a waveform which reflects the
effects of the self-force. As a test of principle, we implement this method
using a 4th-order (1+1) code, and calculate the self-force for the simple case
of a scalar charge moving in a circular orbit around a Schwarzschild black
hole. We achieve agreement with frequency-domain results to ~ 0.1% or better.


title: Status and Results from AMANDA/IceCube

abstract:
  IceCube is a cubic kilometer-scale neutrino telescope under construction at
the South Pole since the austral summer 2004/2005. At the moment it is taking
data with 22 deployed strings. The full detector is expected to be completed in
2011 with up to 80 strings each holding 60 digital optical modules. The
progenitor detector AMANDA has been operating at the same site since 1997 and
is still running as an integral part of IceCube. A summary of AMANDA science
for its 10 years of standalone operations is presented, as well as the status
and first physics results of the IceCube project.


title: Linear forms and complementing sets of integers

abstract:
  Let $\varphi(x_1,\ldots,x_h,y) = u_1x_1 + \cdots + u_hx_h+vy$ be a linear
form with nonzero integer coefficients $u_1,\ldots, u_h, v.$ Let $\mathcal{A} =
(A_1,\ldots, A_h)$ be an $h$-tuple of finite sets of integers and let $B$ be an
infinite set of integers. Define the representation function associated to the
form $\varphi$ and the sets \mca\ and $B$ as follows: $$
R^{(\varphi)}_{\mathcal{A},B}(n) = \text{card}\left( \left\{ (a_1,\ldots,
a_h,b) \in A_1 \times \cdots \times A_h \times B: \varphi(a_1, \ldots , a_h,b )
= n \right\} \right).$$ If this representation function is constant, then the
set $B$ is periodic and the period of $B$ will be bounded in terms of the
diameter of the finite set $\{ \varphi(a_1,\ldots,a_h,0): (a_1,\ldots, a_h) \in
A_1 \times \cdots \times A_h\}.$


title: Globular clusters in the outer halo of M31: the survey

abstract:
  We report the discovery of 40 new globular clusters (GCs) that have been
found in surveys of the halo of M31 based on INT/WFC and CHFT/Megacam imagery.
A subset of these these new GCs are of an extended, diffuse nature, and include
those already found in Huxor et al. (2005). The search strategy is described
and basic positional and V and I photometric data are presented for each
cluster. For a subset of these clusters, K-band photometry is also given. The
new clusters continue to be found to the limit of the survey area (~100 kpc),
revealing that the GC system of M31 is much more extended than previously
realised. The new clusters increase the total number of confirmed GCs in M31 by
approximately 10% and the number of confirmed GCs beyond 1 degree (~14 kpc) by
more than 75%. We have also used the survey imagery as well recent HST archival
data to update the Revised Bologna Catalogue (RBC) of M31 globular clusters.


title:
Short-time behaviour of demand and price viewed through an exactly
  solvable model for heterogeneous interacting market agents

abstract:
  We introduce a stochastic heterogeneous interacting-agent model for the
short-time non-equilibrium evolution of excess demand and price in a stylized
asset market. We consider a combination of social interaction within peer
groups and individually heterogeneous fundamentalist trading decisions which
take into account the market price and the perceived fundamental value of the
asset. The resulting excess demand is coupled to the market price. Rigorous
analysis reveals that this feedback may lead to price oscillations, a single
bounce, or monotonic price behaviour. The model is a rare example of an
analytically tractable interacting-agent model which allows us to deduce in
detail the origin of these different collective patterns. For a natural choice
of initial distribution the results are independent of the graph structure that
models the peer network of agents whose decisions influence each other.


title: A Ricci nilsoliton is nongradient

abstract:
  In this brief note, we clarify that a Ricci nilsoliton cannot be of gradient
type.


title: On the defining relations for generalized q-Schur algebras

abstract:
  We show that the defining relations needed to describe a generalized q-Schur
algebra as a quotient of a quantized enveloping algebra are determined
completely by the defining ideal of a certain finite affine variety, the points
of which correspond bijectively to the set of weights. This explains, unifies,
and extends previous results.


title:
The optimal phase of the generalised Poincare dodecahedral space
  hypothesis implied by the spatial cross-correlation function of the WMAP sky
  maps

abstract:
  Several studies have proposed that the shape of the Universe may be a
Poincare dodecahedral space (PDS) rather than an infinite, simply connected,
flat space. Both models assume a close to flat FLRW metric of about 30% matter
density. We study two predictions of the PDS model. (i) For the correct model,
the spatial two-point cross-correlation function, $\ximc$, of temperature
fluctuations in the covering space, where the two points in any pair are on
different copies of the surface of last scattering (SLS), should be of a
similar order of magnitude to the auto-correlation function, $\xisc$, on a
single copy of the SLS. (ii) The optimal orientation and identified circle
radius for a "generalised" PDS model of arbitrary twist $\phi$, found by
maximising $\ximc$ relative to $\xisc$ in the WMAP maps, should yield $\phi \in
\{\pm 36\deg\}$. We optimise the cross-correlation at scales < 4.0 h^-1 Gpc
using a Markov chain Monte Carlo (MCMC) method over orientation, circle size
and $\phi$. Both predictions were satisfied: (i) an optimal "generalised" PDS
solution was found, with a strong cross-correlation between points which would
be distant and only weakly correlated according to the simply connected
hypothesis, for two different foreground-reduced versions of the WMAP 3-year
all-sky map, both with and without the kp2 Galaxy mask: the face centres are
$(l,b)_{i=1,6}\approx (184d, 62d), (305d, 44d), (46d, 49d), (117d, 20d), (176d,
-4d), (240d, 13d) to within ~2d, and their antipodes; (ii) this solution has
twist \phi= (+39 \pm 2.5)d, in agreement with the PDS model. The chance of this
occurring in the simply connected model, assuming a uniform distribution $\phi
\in [0,2\pi]$, is about 6-9%.


title:
One-point reductions of finite spaces, h-regular CW-complexes and
  collapsibility

abstract:
  We investigate one-point reduction methods of finite topological spaces.
These methods allow one to study homotopy theory of cell complexes by means of
elementary moves of their finite models. We also introduce the notion of
h-regular CW-complex, generalizing the concept of regular CW-complex, and prove
that the h-regular CW-complexes, which are a sort of
combinatorial-up-to-homotopy objects, are modeled (up to homotopy) by their
associated finite spaces. This is accomplished by generalizing a classical
result of McCord on simplicial complexes.


title:
A cubic identity for the Infeld-van der Waerden field and its
  application

abstract:
  A cubic identity for the Infeld-van der Waerden field is found and its
application to verifying an explicit formula for the spinor components of the
metric connection is demonstrated.