title: Superfluidity and phase transitions in a resonant Bose gas

abstract:
  The atomic Bose gas is studied across a Feshbach resonance, mapping out its
phase diagram, and computing its thermodynamics and excitation spectra. It is
shown that such a degenerate gas admits two distinct atomic and molecular
superfluid phases, with the latter distinguished by the absence of atomic
off-diagonal long-range order, gapped atomic excitations, and deconfined atomic
pi-vortices. The properties of the molecular superfluid are explored, and it is
shown that across a Feshbach resonance it undergoes a quantum Ising transition
to the atomic superfluid, where both atoms and molecules are condensed. In
addition to its distinct thermodynamic signatures and deconfined half-vortices,
in a trap a molecular superfluid should be identifiable by the absence of an
atomic condensate peak and the presence of a molecular one.


title: On trapped surface formation in gravitational collapse II

abstract:
  Further to our consideration on trapped surfaces in gravitational collapse,
where pressures were allowed to be negative while satisfying weak energy
condition to avoid trapped surface formation, we discuss here several other
attempts of similar nature in this direction. Certain astrophysical aspects are
pointed out towards examining the physical realization of such a possibility in
realistic gravitational collapse.


title:
Fragment-collision model for compound chondrule formation: Estimation of
  collision probability

abstract:
  We propose a new scenario for compound chondrule formation named as
"fragment-collision model," in the framework of the shock-wave heating model. A
molten cm-sized dust particle (parent) is disrupted in the high-velocity gas
flow. The extracted fragments (ejectors) are scattered behind the parent and
the mutual collisions between them will occur. We modeled the disruption event
by analytic considerations in order to estimate the probability of the mutual
collisions assuming that all ejectors have the same radius. We found that the
estimated collision probability, which is the probability of collisions
experienced by an ejector in one disruption event, can account for the observed
fraction of compound chondrules. In addition, the model predictions are
qualitatively consistent with other observational data (oxygen isotopic
composition, textural types, and size ratios of constituents). Based on these
results, we concluded that this new model can be one of the strongest
candidates for the compound chondrule formation.
  It should be noted that all collisions do not necessarily lead to the
compound chondrule formation. The formation efficiency and the future works
which should be investigated in the forthcoming paper are also discussed.


title: Geometric flows and black hole entropy

abstract:
  Perelman has given a gradient formulation for the Ricci flow, introducing an
``entropy function'' which increases monotonically along the flow.We pursue a
thermodynamic analogy and apply Ricci flow ideas to general relativity. We
investigate whether Perelman's entropy is related to
(Bekenstein-Hawking)geometric entropy as familiar from black hole
thermodynamics. From a study of the fixed points of the flow we conclude that
Perelman entropy is not connected to geometric entropy. However, we notice that
there is a very similar flow which DOES appear to be connected to geometric
entropy. The new flow may find applications in black hole physics suggesting
for instance, new approaches to the Penrose inequality.


title: Equivalence of types and Catlin boundary systems

abstract:
  The D'Angelo finite type is shown to be equivalent to the Kohn finite ideal
type on smooth, pseudoconvex domains in complex n space. This is known as the
Kohn Conjecture. The argument uses Catlin's notion of a boundary system as well
as methods from subanalytic and semialgebraic geometry. When a subset of the
boundary contains only two level sets of the Catlin multitype, a lower bound
for the subelliptic gain in the \bar\partial-Neumann problem is obtained in
terms of the D'Angelo type, the dimension of the ambient space, and the level
of forms.


title: Energy, entropy and the Ricci flow

abstract:
  The Ricci flow is a heat equation for metrics, which has recently been used
to study the topology of closed three manifolds. In this paper we apply Ricci
flow techniques to general relativity. We view a three dimensional
asymptotically flat Riemannian metric as a time symmetric initial data set for
Einstein's equations. We study the evolution of the area A and Hawking mass M
of a two dimensional closed surface under the Ricci flow. The physical
relevance of our study derives from the fact that, in general relativity the
area of apparent horizons is related to black hole entropy and the Hawking mass
of an asymptotic round 2-sphere is the ADM energy.We begin by considering the
special case of spherical symmetry to develop a physical feel for the geometric
quantities involved. We then consider a general asymptotically flat Riemannian
metric and derive an inequality which relates the evolution of the area of a
closed surface S to its Hawking mass. We suggest that there may be a maximum
principle which governs the long term existence of the asymptotically flat
Ricci flow.


title: Bose-Fermi Equivalence in Three Dimensional Non-commutative Space-Time

abstract:
  We study the Fermionisation of Seiberg-Witten mapped action (to order
$\theta$) of the $\lambda\phi^{4}$ theory coupled minimally with U(1) gauge
field governed by Chern-Simon action. Starting from the corresponding partition
function we derive non-perturbatively (in coupling constant) the partition
function of the spin 1/2 theory following Polyakov spin factor formalism. We
find the dual interacting fermionic theory is non local. This feature persist
also in the limit of vanishing self coupling. In $\theta\to 0$ limit, the
commutative result is regained.


title:
Radiative charmless B_{(s)}\to V \gamma and B_{(s)}\to A \gamma decays
  in pQCD approach

abstract:
  We study the radiative charmless $B_{(s)}\to V(A)\gamma $ decays in
perturbative QCD (pQCD) approach to the leading order in $\alpha_s$ (here $V$
and $A$ denotes vector mesons and two kinds of axial-vector mesons: $^3P_1$ and
$^1P_1$ states, respectively.). Our predictions of branching ratios are
consistent with the current available experimental data. We update all
$B_{(s)}\to V$ form factors and give the predictions for $B\to A$ form factors
using the recent hadronic inputs. In addition to the dominant factorizable
spectator diagrams, which is form factor like, we also calculate the so-called
``power suppressed'' annihilation type diagrams, the gluonic penguin, charming
penguin, and two photon diagrams. These diagrams give the main contributions to
direct CP asymmetries, mixing-induced CP asymmetry variables, the isospin
asymmetry and U-spin asymmetry variables. Unlike the branching ratios, these
ratios or observables possess higher theoretical precision in our pQCD
calculation, since they do not depend on the input hadronic parameters too
much. Most of the results still need experimental tests in the on-going and
forthcoming experiments.


title: Automatic analysis of Swift-XRT data

abstract:
  The Swift spacecraft detects and autonomously observes ~100 Gamma Ray Bursts
(GRBs) per year, ~96% of which are detected by the X-ray telescope (XRT). GRBs
are accompanied by optical transients and the field of ground-based follow-up
of GRBs has expanded significantly over the last few years, with rapid response
instruments capable of responding to Swift triggers on timescales of minutes.
To make the most efficient use of limited telescope time, follow-up astronomers
need accurate positions of GRBs as soon as possible after the trigger.
Additionally, information such as the X-ray light curve, is of interest when
considering observing strategy. The Swift team at Leicester University have
developed techniques to improve the accuracy of the GRB positions available
from the XRT, and to produce science-grade X-ray light curves of GRBs. These
techniques are fully automated, and are executed as soon as data are available.


title: Non-adic formal schemes

abstract:
  Our purpose is to make a contribution to the foundation of the theory of
formal scheme. We are interested particularly in non-Noetherian or non-adic
formal schemes, which have been little studied. We redefine the formal scheme
as a proringed space and study its basic properties. We also find several
examples of non-adic formal schemes.


title:
Bayesian approach for g-mode detection, or how to restrict our
  imagination

abstract:
  Nowadays, g-mode detection is based upon a priori theoretical knowledge. By
doing so, detection becomes more restricted to what we can imagine. De facto,
the universe of possibilities is made narrower. Such an approach is pertinent
for Bayesian statisticians. Examples of how Bayesian inferences can be applied
to spectral analysis and helioseismic power spectra are given. Our intention is
not to give the full statistical framework (much too ambitious) but to provide
an appetizer for going further in the direction of a proper Bayesian inference,
especially for detecting gravity modes.


title:
An example of algebraization of analysis and Fibonacci cobweb poset
  characterization

abstract:
  In recent Kwasniewski's papers inspired by O. V. Viskov it was shown that the
$\psi$-calculus in parts appears to be almost automatic, natural extension of
classical operator calculus of Rota - Mullin or equivalently - of umbral
calculus of Roman and Rota. At the same time this calculus is an example of the
algebraization of the analysis - here restricted to the algebra of polynomials.
The first part of the article is the review of the recent author's
contribution. The main definitions and theorems of Finite Fibonomial
  Operator Calculus which is a special case of $\psi$-extented Rota's finite
operator calculus are presented there. In the second part the characterization
of Fibonacci Cobweb poset P as DAG and oDAG is given. The dim 2 poset such that
its Hasse diagram coincide with digraf of P is constructed.


title: VLTI/MIDI 10 micron interferometry of the forming massive star W33A

abstract:
  We report on resolved interferometric observations with VLTI/MIDI of the
massive young stellar object (MYSO) W33A. The MIDI observations deliver
spectrally dispersed visibilities with values between 0.03 and 0.06, for a
baseline of 45m over the wavelength range 8-13 micron. The visibilities
indicate that W33A has a FWHM size of approximately 120AU (0.030'') at 8 micron
which increases to 240AU at 13 micron, scales previously unexplored among
MYSOs. This observed trend is consistent with the temperature falling off with
distance. 1D dust radiative transfer models are simultaneously fit to the
visibility spectrum, the strong silicate feature and the shape of the mid
infrared spectral energy distribution (SED). For any powerlaw density
distribution, we find that the sizes (as implied by the visibilities) and the
stellar luminosity are incompatible. A reduction to a third of W33A's
previously adopted luminosity is required to match the visibilities; such a
reduction is consistent with new high resolution 70 micron data from Spitzer's
MIPSGAL survey. We obtain best fits for models with shallow dust density
distributions of r^(-0.5) and r^(-1.0) and for increased optical depth in the
silicate feature produced by decreasing the ISM ratio of graphite to silicates
and using optical grain properties by Ossenkopf et al. (1992).


title: Terahertz detection with delta-doped GaAs/AlAs multiple quantum wells

abstract:
  The authors demonstrate selective detection of terahertz radiation employing
beryllium delta-doped GaAs/AlAs multiple quantum wells. The sensitivity up to 1
V/W within 4.2-7.3 THz range at liquid helium temperatures is reached. The
Franz-Keldysh oscillations observed in photo- and electro-reflectance spectra
allowed one to estimate built-in electric fields in the structures studied. It
was found that the electric field strength in the cap layer region could vary
from 10 kV/cm up to 26 kV/cm, depending on the structure design and
temperature.


title: A new equation of state for dark energy

abstract:
  In the contemporary Cosmology, dark energy is modeled as a perfect fluid,
having a very simple equation of state: pressure is proportional to dark energy
density. As an alternative, I propose a more complex equation of state, with
pressure being function of three variables: dark energy density, matter density
and the size of the Universe. One consequence of the new equation is that, in
the late-time Universe, cosmological scale factor is linear function of time;
while the standard cosmology predicts an exponential function.The new equation
of state allows attributing a temperature to the physical vacuum, a temperature
proportional to the acceleration of the expansion of the Universe. The vacuum
temperature decreases with the expansion of the Universe, approaching (but
never reaching) the absolute zero.


title:
Magnetic Properties in Non-centrosymmetric Superconductors with and
  without Antiferromagnetic Order

abstract:
  The paramagnetic properties in non-centrosymmetric superconductors with and
without antiferromagnetic (AFM) order are investigated with focus on the heavy
Fermion superconductors, CePt_3Si, CeRhSi_3 and CeIrSi_3. First, we investigate
the spin susceptibility in the linear response regime and elucidate the role of
AFM order. The spin susceptibility at T=0 is independent of the pairing
symmetry and increases in the AFM state. Second, the non-linear response to the
magnetic field are investigated on the basis of an effective model for CePt_3Si
which may be also applicable to CeRhSi_3 and CeIrSi_3. The role of
antisymmetric spin-orbit coupling (ASOC), helical superconductivity,
anisotropic Fermi surfaces and AFM order are examined in the dominantly s-, p-
and d-wave states. We emphasize the qualitatively important role of the mixing
of superconducting (SC) order parameters in the p-wave state which enhances the
spin susceptibility and suppresses paramagnetic depairing effect in a
significant way. Therefore, the dominantly p-wave superconductivity admixed
with the s-wave order parameter is consistent with the paramagnetic properties
of CePt_3Si at ambient pressure. We propose some experiments which can
elucidate the novel pairing states in CePt_3Si as well as CeRhSi_3 and
CeIrSi_3.


title: Generalized conformal realizations of Kac-Moody algebras

abstract:
  We present a construction which associates an infinite sequence of Kac-Moody
algebras, labeled by a positive integer n, to one single Jordan algebra. For
n=1, this reduces to the well known Kantor-Koecher-Tits construction. Our
generalization utilizes a new relation between different generalized Jordan
triple systems, together with their known connections to Jordan and Lie
algebras. Applied to the Jordan algebra of hermitian 3x3 matrices over the
division algebras R, C, H, O, the construction gives the exceptional Lie
algebras f4, e6, e7, e8 for n=2. Moreover, we obtain their infinite-dimensional
extensions for n greater or equal to 3. In the case of 2x2 matrices the
resulting Lie algebras are of the form so(p+n,q+n) and the concomitant
nonlinear realization generalizes the conformal transformations in a spacetime
of signature (p,q).


title: A catalogue of singularities

abstract:
  This paper is an attempt to classify finite-time singularities of PDEs. Most
of the problems considered describe free-surface flows, which are easily
observed experimentally. We consider problems where the singularity occurs at a
point, and where typical scales of the solution shrink to zero as the
singularity is approached. Upon a similarity transformation, exact self-similar
behaviour is mapped to the fixed point of a {\it infinite dimensional dynamical
system} representing the original dynamics. We show that the dynamics close to
the fixed point is a useful way classifying the structure of the singularity.
Specifically, we consider various types of stable and unstable fixed points,
centre-manifold dynamics, limit cycles, and chaotic dynamics.


title:
Deconfinement Phase Transition Heating and Thermal Evolution of Neutron
  Stars

abstract:
  The deconfinement phase transition will lead to the release of latent heat
during spins down of neutron stars if the transition is the first-order one.We
have investigated the thermal evolution of neutron stars undergoing such
deconfinement phase transition. The results show that neutron stars may be
heated to higher temperature.This feature could be particularly interesting for
high temperature of low-magnetic field millisecond pulsar at late stage.


title:
Quantum Field Theories Coupled to Supergravity: AdS/CFT and Local
  Couplings

abstract:
  This article is based on my PhD thesis and covers the following topics:
Holographic meson spectra in a dilaton flow background, the mixed Coulomb-Higgs
branch in terms of instantons on D7 branes, and a dual description of
heavy-light mesons. Moreover, in a second part the conformal anomaly of four
dimensional supersymmetric quantum field theories coupled to classical N=1
supergravity is explored in a superfield formulation. The complete basis for
the anomaly and consistency conditions, which arise from cohomological
considerations, are given. Possible implications for an extension of
Zamolodchikov's c-theorem to four dimensional supersymmetric quantum field
theories are discussed.


abstract:
  A new family of maximal curves over a finite field is presented and some of
their properties are investigated.


title: Asymptotic Properties of Hilbert Geometry

abstract:
  We show that the spheres in Hilbert geometry have the same volume growth
entropy as those in the Lobachevsky space. We give the asymptotic estimates for
the ratio of the volume of metric ball to the area of the metric sphere in
Hilbert geometry. Derived estimates agree with the well-known fact in the
Lobachevsky space


title:
Publier sous l'Occupation I. Autour du cas de Jacques Feldbau et de
  l'Acad\'emie des sciences

abstract:
  This is an article on mathematical publishing during the German occupation of
France. Looking at the cases of four of them and especially at the case of
Jacques Feldbau (one of the founders of the theory of fibre bundles), we
investigate the way censorship struck the French mathematicians who declared
jewish by the Statut des juifs of october 1940, and the strategies these
mathematicians then developed. The way the Vichy laws have been discussed and
applied at the Acad\'emie des sciences is investigated.


title: A new class of invariants in the lepton sector

abstract:
  We construct a new set of combinations from the mass matrices of the charged
leptons and neutrinos that are invariant under basis transformation, hereafter
{\it the} invariants. We use these invariants to study various symmetries and
neutrino mass textures in a basis independent way. In particular, we show that
by using these invariants the ansatz such as $\mu-\tau$ exchange and reflection
symmetries, various texture zeros and flavor symmetries can be expressed in a
general basis.


title: Sinusoidal excitations in reduced Maxwell-Duffing model

abstract:
  Sinusoidal wave solutions are obtained for reduced Maxwell-Duffing equations
describing the wave propagation in a non-resonant atomic medium. These
continuous wave excitations exist when the medium is initially polarized by an
electric field. Other obtained solutions include both mono-frequency and
cnoidal waves.


title: A few remarks about the Pioneer anomaly

abstract:
  Some features of the Pioneer anomaly are discussed in context of author's
explanation of this effect as a deceleration of the probes in the graviton
background. It is noted that if the model is true then the best parameter of
the anomalous acceleration should be not the distance to the Sun but a cosine
of the angle between a velocity of the probe and its radius-vector.


title:
The singular points of self-similar functions with zero spectral degree.
  Stieltjes self-similar string

abstract:
  The self-similar functions of zero spectral degree are defined. The singular
points of these functions are investigated and full classification of points is
given. The connection with spectral problems (Stieltjes string) is pointed out.


title: Light and Electromagnetic Waves Teaching in Engineering Education

abstract:
  Suggestion of physics laboratory exercises and discussion of the physics
laboratory curricula for engineering majors where the properties of light and
electromagnetic waves are studied in parallel. It is shown that one of the
important educational advantages of an experimental study of the properties of
microwaves as an example of electromagnetic waves simultaneously with the
properties of light are, on one hand, visualization of the properties of
microwaves, and on the other hand, provide evidences that light is an
electromagnetic wave.


title: Inner-shell Annihilation of Positrons in Argon, Iron and Copper Atoms

abstract:
  The annihilation parameters of positrons with electrons in different shells
of Argon, Iron and Copper atoms are calculated below the positronium (Ps)
formation thresholds. Quite accurate ab initio calculations of the bound state
wavefunctions of Argon, Iron and Copper orbitals are obtained from Cowan
computer code. A least-squares variational method (LSVM) is used for
determining the wavefunction of the positrons. The program is employed for
calculating the s-wave partial cross sections of positrons scattered by Iron
and Copper atoms. Our results of the effective charge are compared with
available experimental and theoretical ones. --


title: Driving light pulses with light in two-level media

abstract:
  A two-level medium, described by the Maxwell-Bloch (MB) system, is engraved
by establishing a standing cavity wave with a linearly polarized
electromagnetic field that drives the medium on both ends. A light pulse,
polarized along the other direction, then scatters the medium and couples to
the cavity standing wave by means of the population inversion density
variations. We demonstrate that control of the applied amplitudes of the
grating field allows to stop the light pulse and to make it move backward
(eventually to drive it freely). A simplified limit model of the MB system with
variable boundary driving is obtained as a discrete nonlinear Schroedinger
equation with tunable external potential. It reproduces qualitatively the
dynamics of the driven light pulse.

categories: physics.optics cond-mat.other nlin.PS physics.class-ph


title:
Cost and Capacity of Signaling in the Escherichia coli Protein Reaction
  Network

abstract:
  In systems biology new ways are required to analyze the large amount of
existing data on regulation of cellular processes. Recent work can be roughly
classified into either dynamical models of well-described subsystems, or
coarse-grained descriptions of the topology of the molecular networks at the
scale of the whole organism. In order to bridge these two disparate approaches
one needs to develop simplified descriptions of dynamics and topological
measures which address the propagation of signals in molecular networks. Here,
we consider the directed network of protein regulation in E. coli,
characterizing its modularity in terms of its potential to transmit signals. We
demonstrate that the simplest measure based on identifying sub-networks of
strong components, within which each node could send a signal to every other
node, indeed partitions the network into functional modules. We then suggest
measures to quantify the cost and spread associated with sending a signal
between any particular pair of proteins. Thereby, we address the signalling
specificity within and between modules, and show that in the regulation of
E.coli there is a systematic reduction of the cost and spread for signals
traveling over more than two intermediate reactions.


title: High-Precision Tests of the MSSM with GigaZ

abstract:
  We review the physics potential of the GigaZ option of the International
Linear Collider (ILC) for probing the Minimal Supersymmetric Standard Model
(MSSM) via the sensitivity of the electroweak precision observables measured at
the ILC to quantum corrections. A particular focus is put on the effective
leptonic weak mixing angle, sin^2_theta_eff. The MSSM predictions take into
account the complete one-loop results including the full complex phase
dependence, all available MSSM two-loop corrections as well as the full
Standard Model (SM) results. We find that the anticipated experimental accuracy
at the ILC with GigaZ option may resolve the virtual effects of SUSY particles
even in scenarios where the SUSY particles are so heavy that they escape direct
detection at the LHC and the first phase of the ILC.


title:
Form-factors in the Baxter-Bazhanov-Stroganov model II: Ising model on
  the finite lattice

abstract:
  We continue our investigation of the Baxter-Bazhanov-Stroganov or
\tau^{(2)}-model using the method of separation of variables
[nlin/0603028,arXiv:0708.4342]. In this paper we derive for the first time the
factorized formula for form-factors of the Ising model on a finite lattice
conjectured previously by A.Bugrij and O.Lisovyy in
[arXiv:0708.3625,arXiv:0708.3643]. We also find the matrix elements of the spin
operator for the finite quantum Ising chain in a transverse field.

categories: nlin.SI cond-mat.stat-mech math-ph math.MP


title:
Bayesian finite mixtures: a note on prior specification and posterior
  computation

abstract:
  A new method for the computation of the posterior distribution of the number
k of components in a finite mixture is presented. Two aspects of prior
specification are also studied: an argument is made for the use of a Poisson(1)
distribution as the prior for k; and methods are given for the selection of
hyperparameter values in the mixture of normals model, with natural conjugate
priors on the components parameters.


title:
Rotating ground states of a one-dimensional spin-polarized gas of
  fermionic atoms with attractive p-wave interactions on a mesoscopic ring

abstract:
  The major finding of this paper is that a one-dimensional spin-polarized gas
comprised of an even number of fermionic atoms interacting via attractive
p-wave interactions and confined to a mesoscopic ring has a degenerate pair of
ground states that are oppositely rotating. In any realization the gas will
thus spontaneously rotate one way or the other in spite of the fact that there
is no external rotation or bias fields. Our goal is to show that this
counter-intuitive finding is a natural consequence of the combined effects of
quantum statistics, ring topology, and exchange interactions.


title:
Terahertz sensing by beryllium and silicon delta-doped GaAs/AlAs quantum
  wells

abstract:
  Selective sensing of terahertz (THz) radiation by beryllium and silicon
delta-doped GaAs/AlAs multiple quantum wells (MQWs) is demonstrated. A
sensitivity up to 0.3 V/W within 0.5{4.2 THz in silicon- and up to 1 V/W within
4.2-7.3 THz range in beryllium-doped MQWs at liquid helium temperatures is
shown. The built-in electric fields as estimated from the observed
Franz-Keldysh oscillations in photoreflectance spectra were found to be located
close to the cap and buffer layers of MQWs and vary from 18 kV/cm up to 49
kV/cm depending on the structure design.


title: The Boson Peak and its Relation with Acoustic Attenuation in Glasses

abstract:
  Experimental results on the density of states and on the acoustic modes of
glasses in the THz region are compared to the predictions of two categories of
models. A recent one, solely based on an elastic instability, does not account
for most observations. Good agreement without adjustable parameters is obtained
with models including the existence of non-acoustic vibrational modes at THz
frequency, providing in many cases a comprehensive picture for a range of glass
anomalies.


title: Perfect many-to-one teleportation with stabilizer states

abstract:
  We study the possibility of performing perfect teleportation of unknown
quantum states from multiple senders to a single receiver with a previously
shared stabilizer state. In the model we considered, the utilized stabilizer
state is partitioned into several subsystems and then each subsystem is
distributed to a distinct party. We present two sufficient conditions for a
stabilizer state to achieve a given nonzero teleportation capacity with respect
to a given partition plan. The corresponding teleportation protocols are also
explicitly given. Interestingly, we find that even mixed stabilizer states are
also useful for perfect many-to-one teleportation. Finally, our work provides a
new perspective from stabilizer formalism to view the standard teleportation
protocol and also suggests a new technique for analyzing teleportation
capability of multipartite entangled states.


title:
On the structure and representations of the insertion-elimination Lie
  algebra

abstract:
  We examine the structure of the insertion-elimination Lie algebra on rooted
trees introduced in \cite{CK}. It possesses a triangular structure $\g = \n_+
\oplus \mathbb{C}.d \oplus \n_-$, like the Heisenberg, Virasoro, and affine
algebras. We show in particular that it is simple, which in turn implies that
it has no finite-dimensional representations. We consider a category of
lowest-weight representations, and show that irreducible representations are
uniquely determined by a "lowest weight" $\lambda \in \mathbb{C}$. We show that
each irreducible representation is a quotient of a Verma-type object, which is
generically irreducible.


title:
Hypergeometric Systems in two Variables, Quivers, Dimers and Dessins
  d'Enfants

abstract:
  This paper presents some parallel developments in Quiver/Dimer Models,
Hypergeometric Systems and Dessins d'Enfants. The setting in which Gelfand,
Kapranov and Zelevinsky have formulated the theory of hypergeometric systems,
provides also a natural setting for dimer models. The Fast Inverse Algorithm,
the untwisting procedure and the Kasteleyn matrix for dimer models are recasted
in this setting. There is a relation between triangulations in GKZ theory and
some perfect matchings in the dimer models, so that the secondary polygon
coincides with the Newton polygon of the Kasteleyn determinant. Finally it is
observed in examples and conjectured to hold in general, that the determinant
of the Kasteleyn matrix with suitable weights becomes after a simple
transformation equal to the principal A-determinant in GKZ theory.


title: Generic Properties of Homogeneous Ricci Solitons

abstract:
  We discuss the geometry of homogeneous Ricci solitons. After showing the
nonexistence of compact homogeneous and noncompact steady homogeneous solitons,
we concentrate on the study of left invariant Ricci solitons. We show that, in
the unimodular case, the Ricci soliton equation does not admit solutions in the
set of left invariant vector fields. We prove that a left invariant soliton of
gradient type must be a Riemannian product with a nontrivial Euclidean de Rham
factor. As an application of our results we prove that any generalized metric
Heisenberg Lie group is a nongradient left invariant Ricci soliton of expanding
type.


title: A Model for Dark Matter Halos

abstract:
  A halo model is presented which possesses a constant phase space density (Q)
core followed by a radial CDM-like power law decrease in Q. The motivation for
the core is the allowance for a possible primordial phase space density limit
such as the Tremaine-Gunn upper bound. The space density profile derived from
this model has a constant density core and falls off rapidly beyond. The new
model is shown to improve the fits to the observations of LSB galaxy rotation
curves, naturally provides a model which has been shown to result in a
lengthened dynamical friction time scale for the Fornax dwarf spheroidal galaxy
and predicts a flattening of the density profile within the Einstein radius of
galaxy clusters. A constant gas entropy floor is predicted whose adiabatic
constant provides a lower limit in accord with observed galaxy cluster values.
While `observable-sized' cores are not seen in standard cold dark matter (CDM)
simulations, phase space considerations suggest that they could appear in warm
dark matter (WDM) cosmological simulations and in certain hierarchically
consistent SuperWIMP scenarios.


title:
Verifying the Identity of High-Redshift Massive Galaxies Through the
  Clustering of Lower Mass Galaxies Around Them

abstract:
  Massive high-redshift galaxies form in over-dense regions where the
probability of forming other galaxies is also strongly enhanced. Given an
observed flux of a galaxy, the inferred mass of its host halo tends to be
larger as its inferred redshift increases. As the mass and redshift of a galaxy
halo increase, the expected clustering of other galaxies around it gets
stronger. It is therefore possible to verify the high-redshift identity of a
galaxy (prior to an unambiguous spectral identification) from the clustering of
other galaxies around it. We illustrate this method for the massive galaxy
suggested by Mobasher et al. (2005) to be at redshift z~6.5. If this galaxy
were to exist at z~6.5, there should have been a mean of ~10 galaxies larger
than a hundredth of its mass and having z-band magnitudes less than ~25
detected as i-dropouts in the HUDF. We calculate an approximate probability
distribution for neighbor galaxies and determine that there is less than a
~0.3% chance of detecting no massive neighbor galaxies. The lack of other
massive z~6.5 galaxies in the HUDF image argues that the Mobasher et al. (2005)
galaxy is instead a low redshift interloper. We generalize our results to other
galaxy masses and redshifts.


title: Statistical Mechanical Models and Topological Color Codes

abstract:
  We find that the overlapping of a topological quantum color code state,
representing a quantum memory, with a factorized state of qubits can be written
as the partition function of a 3-body classical Ising model on triangular or
Union Jack lattices. This mapping allows us to test that different
computational capabilities of color codes correspond to qualitatively different
universality classes of their associated classical spin models. By generalizing
these statistical mechanical models for arbitrary inhomogeneous and complex
couplings, it is possible to study a measurement-based quantum computation with
a color code state and we find that their classical simulatability remains an
open problem. We complement the meaurement-based computation with the
construction of a cluster state that yields the topological color code and this
also gives the possibility to represent statistical models with external
magnetic fields.


title: A search for ortho-benzyne (o-C6H4) in CRL 618

abstract:
  Polycyclic aromatic hydrocarbons (PAHs) have been proposed as potential
carriers of the unidentified infrared bands (UIRs) and the diffuse interstellar
bands (DIBs). PAHs are not likely to form by gas-phase or solid-state
interstellar chemistry, but rather might be produced in the outflows of
carbon-rich evolved stars. PAHs could form from acetylene addition to the
phenyl radical (C6H5), which is closely chemically related to benzene (C6H6)
and ortho-benzyne (o-C6H4). To date, circumstellar chemical models have been
limited to only a partial treatment of benzene-related chemistry, and so the
expected abundances of these species are unclear. A detection of benzene has
been reported in the envelope of the proto-planetary nebula (PPN) CRL 618, but
no other benzene-related species has been detected in this or any other source.
The spectrum of o-C6H4 is significantly simpler and stronger than that of C6H5,
and so we conducted deep Ku-, K- and Q-band searches for o-C6H4 with the Green
Bank Telescope. No transitions were detected, but an upper limit on the column
density of 8.4x10^13 cm^-2 has been determined. This limit can be used to
constrain chemical models of PPNe, and this study illustrates the need for
complete revision of these models to include the full set of benzene-related
chemistry.


title: Free streaming in mixed dark matter

abstract:
  Free streaming in a \emph{mixture} of collisionless non-relativistic dark
matter (DM) particles is studied by implementing methods from the theory of
multicomponent plasmas. The mixture includes Fermionic, condensed and non
condensed Bosonic particles decoupling in equilibrium while relativistic, heavy
non-relativistic thermal relics (WIMPs), and sterile neutrinos that decouple
\emph{out of equilibrium} when they are relativistic. The free-streaming length
$\lambda_{fs}$ is obtained from the marginal zero of the gravitational
polarization function, which separates short wavelength Landau-damped from long
wavelength Jeans-unstable \emph{collective} modes. At redshift $z$ we find $
\frac{1}{\lambda^2_{fs}(z)}= \frac{1}{(1+z)} \big[\frac{0.071}{\textrm{kpc}}
\big]^2 \sum_{a}\nu_a g^{2/3}_{d,a}({m_a}/{\mathrm{keV}})^2 I_a $,where $0\leq
\nu_a \leq 1$ are the \emph{fractions} of the respective DM components of mass
$m_a$ that decouple when the effective number of ultrarelativistic degrees of
freedom is $g_{d,a}$, and $I_a$ only depend on the distribution functions at
decoupling, given explicitly in all cases. If sterile neutrinos produced either
resonantly or non-resonantly that decouple near the QCD scale are the
\emph{only} DM component,we find $\lambda_{fs}(0) \simeq 7 \mathrm{kpc}
(\mathrm{keV}/m)$ (non-resonant), $\lambda_{fs}(0) \simeq 1.73 \mathrm{kpc}
(\mathrm{keV}/m)$ (resonant).If WIMPs with $m_{wimp} \gtrsim 100 \mathrm{GeV}$
decoupling at $T_d \gtrsim 10 \mathrm{MeV}$ are present in the mixture with
$\nu_{wimp} \gg 10^{-12}$,$\lambda_{fs}(0) \lesssim 6.5 \times 10^{-3}
\mathrm{pc}$ is \emph{dominated} by CDM. If a Bose Einstein condensate is a DM
component its free streaming length is consistent with CDM because of the
infrared enhancement of the distribution function.


title: Prediction for discrete time series

abstract:
  Let $\{X_n\}$ be a stationary and ergodic time series taking values from a
finite or countably infinite set ${\cal X}$. Assume that the distribution of
the process is otherwise unknown. We propose a sequence of stopping times
$\lambda_n$ along which we will be able to estimate the conditional probability
$P(X_{\lambda_n+1}=x|X_0,...,X_{\lambda_n})$ from data segment
$(X_0,...,X_{\lambda_n})$ in a pointwise consistent way for a restricted class
of stationary and ergodic finite or countably infinite alphabet time series
which includes among others all stationary and ergodic finitarily Markovian
processes. If the stationary and ergodic process turns out to be finitarily
Markovian (among others, all stationary and ergodic Markov chains are included
in this class) then $ \lim_{n\to \infty} {n\over \lambda_n}>0$ almost surely.
If the stationary and ergodic process turns out to possess finite entropy rate
then $\lambda_n$ is upperbounded by a polynomial, eventually almost surely.


title: Order estimation of Markov chains

abstract:
  We describe estimators $\chi_n(X_0,X_1,...,X_n)$, which when applied to an
unknown stationary process taking values from a countable alphabet ${\cal X}$,
converge almost surely to $k$ in case the process is a $k$-th order Markov
chain and to infinity otherwise.


title: Model Structures on the Category of Small Double Categories

abstract:
  In this paper we obtain several model structures on {\bf DblCat}, the
category of small double categories. Our model structures have three sources.
We first transfer across a categorification-nerve adjunction. Secondly, we view
double categories as internal categories in {\bf Cat} and take as our weak
equivalences various internal equivalences defined via Grothendieck topologies.
Thirdly, {\bf DblCat} inherits a model structure as a category of algebras over
a 2-monad. Some of these model structures coincide and the different points of
view give us further results about cofibrant replacements and cofibrant
objects. As part of this program we give explicit descriptions and discuss
properties of free double categories, quotient double categories, colimits of
double categories, several nerves, and horizontal categorification.


title:
Electric field gradient induced effects in GaAs/AlGaAs modulation-doped
  structures and high frequency sensing

abstract:
  Electric field gradient effects induced by an asymmetrically in-plane shaped
GaAs/AlGaAs modulation-doped structures of various design are investigated
within 4-300 K temperature range. It is demonstrated that current-voltage
characteristics of such structures at low, 4-80 K, temperatures exhibit
well-pronounced asymmetry arising due to a presence of two different gradients
of the electric field in a two dimensional electron gas. This phenomenon is
caused by both, different accumulation of two-dimensional electrons due to
asymmetrical shape of the structure and nonlocality in the electron drift
velocity. Experiments are illustrated by a phenomenological model and Monte
Carlo simulation. Possible applications of the effect to detect electromagnetic
radiation of GHz and THz frequencies are discussed as well.


title:
Local Indistinguishability and Possibility of Hiding cbits in Activable
  Bound Entangled States

abstract:
  In this letter we prove local indistinguishability of four orthogonal
activable bound entangled states shared among even number of parties. All
reduced density matrices of such states are maximally mixed. We further proceed
to establish a multipartite quantum data hiding scheme on those states and
explore its power and limitations.


title: A pastiche on embeddings into simple groups (following P. E. Schupp)

abstract:
  Let lambda be an infinite cardinal number and let C = {H_i| i in I} be a
family of nontrivial groups. Assume that |I|<=lambda, |H_i|<= lambda, for i in
I, and at least one member of C achieves the cardinality lambda.
  We show that there exists a simple group S of cardinality lambda that
contains an isomorphic copy of each member of C and, for all H_i, H_j in C with
|H_j|=lambda, is generated by the copies of H_i and H_j in S.
  This generalizes a result of Paul E. Schupp (moreover, our proof follows the
same approach based on small cancelation). In the countable case, we partially
recover a much deeper embedding result of Alexander Yu. Ol'shanskii.


title: Noncommutative geometry and motives (a quoi servent les endomotifs?)

abstract:
  This paper gives a short and historical survey on the theory of pure motives
in algebraic geometry and reviews some of the recent developments of this
theory in noncommutative geometry. The second part of the paper outlines the
new theory of endomotives and some of its relevant applications in
number-theory.


title: Quasi-Sectorial Contractions

abstract:
  We revise the notion of the quasi-sectorial contractions. Our main theorem
establishes a relation between semigroups of quasi-sectorial contractions and a
class of m-sectorial generators. We discuss a relevance of this kind of
contractions to the theory of operator-norm approximations of strongly
continuous semigroups.


title: Spin-echo of a single electron spin in a quantum dot

abstract:
  We report a measurement of the spin-echo decay of a single electron spin
confined in a semiconductor quantum dot. When we tip the spin in the transverse
plane via a magnetic field burst, it dephases in 37 ns due to the Larmor
precession around a random effective field from the nuclear spins in the host
material. We reverse this dephasing to a large extent via a spin-echo pulse,
and find a spin-echo decay time of about 0.5 microseconds at 70 mT. These
results are in the range of theoretical predictions of the electron spin
coherence time governed by the dynamics of the electron-nuclear system.


title: A competing order scenario of two-gap behavior in hole doped cuprates

abstract:
  Angle-dependent studies of the gap function provide evidence for the
coexistence of two distinct gaps in hole doped cuprates, where the gap near the
nodal direction scales with the superconducting transition temperature $T_c$,
while that in the antinodal direction scales with the pseudogap temperature. We
present model calculations which show that most of the characteristic features
observed in the recent angle-resolved photoemission spectroscopy (ARPES) as
well as scanning tunneling microscopy (STM) two-gap studies are consistent with
a scenario in which the pseudogap has a non-superconducting origin in a
competing phase. Our analysis indicates that, near optimal doping,
superconductivity can quench the competing order at low temperatures, and that
some of the key differences observed between the STM and ARPES results can give
insight into the superlattice symmetry of the competing order.


title: On q-deformed Stirling numbers

abstract:
  The purpose of this article is to introduce q-deformed Stirling numbers of
the first and second kinds. Relations between these numbers, Riemann zeta
function and q-Bernoulli numbers of higher order are given. Some relations
related to the classical Stirling numbers and Bernoulli numbers of higher order
are found. By using derivative operator to the generating function of the
q-deformed Stirling numbers of the second kinds, a new function is defined
which interpolates the q-deformed Stirling numbers of the second kinds at
negative integers. The recurrence relations of the Stirling numbers of the
first and second kind are given. In addition, relation between q-deformed
Stirling numbers and q-Bell numbers is obtained.


title: Transient Phenomena in Anomalous X-ray Pulsars

abstract:
  In 2003 a previously unpulsed Einstein and ROSAT source cataloged as soft and
dim (Lx of few 10^33 ergs) thermal emitting object, namely XTE J1810-197, was
identified as the first unambiguous transient Anomalous X-ray Pulsar. Two years
later this source was also found to be a bright highly polarized transient
radio pulsar, a unique property among both AXPs and radio pulsars. In September
2006 the Swift Burst Alert Telescope (BAT) detected an intense burst from the
candidate AXP CXOU J164710.2-455216, which entered in an outburst state
reaching a peak emission of at least a factor of 300 higher than quiescence.
Here, we briefly outline the recent results concerning the outburst phenomena
observed in these two AXPs. In particular, XTE J1810-197 has probed to be a
unique laboratory to monitor the timing and spectral properties of a
cooling/fading AXP, while new important information have been inferred from
X-ray and radio band simultaneous observations. CXOU J164710.2-455216 has been
monitored in X-rays and radio bands since the very beginning of its outbursting
state allowing us to cover the first phases of the outburst and to study the
timing and spectral behavior during the first months.


title: Prospects for the Zee-Babu Model at the LHC and low energy experiments

abstract:
  We analyze the viability of the Zee-Babu model as an explanation of observed
neutrino masses and mixings and the possibility that the model is confirmed or
discarded in experiments planned for the very close future. The allowed
parameter space is studied analytically by using some approximations and
partial data. Then, a complete scanning of all parameters and constraints is
performed numerically by using Monte Carlo methods. The cleanest signal of the
model will be the detection of the doubly charged scalar at the LHC and its
correlation with measurements of the branching ratio of $\mu\to e\gamma$ at the
MEG experiment. In addition, the model offers interesting predictions for
$\tau^{-}\to\mu^{+}\mu^{-}\mu^{-}$ experiments, lepton-hadron universality
tests, the $\theta_{13}$ mixing in neutrino oscillations and the
$<m_{\nu}>_{ee}$ parameter of neutrinoless double beta decay.


title: Idempotent ultrafilters and polynomial recurrence

abstract:
  We give a new proof of a polynomial recurrence result due to Bergelson,
Furstenberg, and McCutcheon, using idempotent ultrafilters instead of
IP-limits.


title: Hole transport in p-type GaAs quantum dots and point contacts

abstract:
  Strong spin-orbit interaction characteristic for p-type GaAs systems, makes
such systems promising for the realization of spintronic devices. Here we
report on transport measurements in nanostructures fabricated on p-type,
C-doped GaAs heterostructures by scanning probe oxidation lithography. We
observe conductance quantization in a quantum point contact, as well as
pronounced Coulomb resonances in two quantum dots with different geometries.
Charging energies for both dots, extracted from Coulomb diamond measurements
are in agreement with the lithographic dimensions of the dots. The absence of
excited states in Coulomb diamond measurements indicates that the dots are in
the multi-level transport regime.


title: Triangular Peg Solitaire Unlimited

abstract:
  Triangular peg solitaire is a well-known one-person game or puzzle. When one
peg captures many pegs consecutively, this is called a sweep. We investigate
whether the game can end in a dramatic fashion, with one peg sweeping all
remaining pegs off the board. For triangular boards of side 6 and 8 (with 21
and 36 holes, respectively) the geometrically longest sweep can occur as the
final move in a game. On larger triangular boards, we demonstrate how to
construct solutions that finish with arbitrarily long sweeps. We also consider
the problem of finding solutions that minimize the total number of moves (where
a move is one or more consecutive jumps by the same peg).


title:
On connecting the dynamics of the chromosphere and transition region
  with Hinode SOT and EIS

abstract:
  We use coordinated Hinode SOT/EIS observations that include high-resolution
magnetograms, chromospheric and TR imaging and TR/coronal spectra in a first
test to study how the dynamics of the TR are driven by the highly dynamic
photospheric magnetic fields and the ubiquitous chromospheric waves. Initial
analysis shows that these connections are quite subtle and require a
combination of techniques including magnetic field extrapolations,
frequency-filtered time-series and comparisons with synthetic chromospheric and
TR images from advanced 3D numerical simulations. As a first result, we find
signatures of magnetic flux emergence as well as 3 and 5 mHz wave power above
regions of enhanced photospheric magnetic field in both chromospheric,
transition region and coronal emission.


title: Holographic Dark Matter and Higgs

abstract:
  We identify possible dark matter candidates within the class of strongly
interacting models where electroweak symmetry breaking is triggered by a light
composite Higgs boson. In these models, the Higgs boson emerges as a
Holographic pseudo-goldstone boson, while dark matter can be identified as a
fermionic composite state X^0, which is made stable through a conserved
(``dark'') quantum number. An effective lagrangian description of both the
Higgs and dark matter is proposed, that includes higher-dimensional operators
suppressed by an scale \Lambda_i. These operators will induce deviations from
the standard Higgs properties that could be meassured at future colliders
(LHC,ILC), and thus provide information on the dark matter scale. The dark
matter X^0, is expected to have a mass of order O(TeV), which is in agreement
with the values extracted from the cosmological bounds and the experimental
searches for dark matter.


title: Aharonov-Bohm oscillations in p-type GaAs quantum rings

abstract:
  We have explored phase coherent transport of holes in two p-type GaAs quantum
rings with orbital radii 420 nm and 160 nm fabricated with AFM oxidation
lithography. Highly visible Aharonov-Bohm (AB) oscillations are measured in
both rings, with an amplitude of the oscillations exceeding 10% of the total
resistance in the case of the ring with a radius of 160 nm. Beside the h/e
oscillations, we resolve the contributions from higher harmonics of the AB
oscillations. The observation of a local resistance minimum at B=0 T in both
rings is a signature of the destructive interference of the holes' spins. We
show that this minimum is related to the minimum in the h/2e oscillations.


title: Two new multi-component BKP hierarchies

abstract:
  We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy
based on the eigenfunction symmetry reduction and nonstandard reduction,
respectively. The first one contains two types of BKP equation with
self-consistent sources which Lax representations are presented. The two mcBKP
hierarchies both admit reductions to the $k-$constrained BKP hierarchy and to
integrable (1+1)-dimensional hierarchy with self-consistent sources, which
include two types of SK equation with self-consistent sources and of
bi-directional SK equations with self-consistent sources.


title: Community Detection in Complex Networks Using Genetic Algorithms

abstract:
  Community detection is an important research topic in complex networks. We
present the employment of a genetic algorithm to detect communities in complex
networks which is based on optimizing network modularity. It does not need any
prior knowledge about the number of communities. Its performance is tested on
two real life networks with known community structures and a set of synthetic
networks. As the performance measure an information theoretical metric
variation of information is used. The results are promising and in some cases
better than previously reported studies.


title:
Strong spin-orbit interactions and weak antilocalization in carbon doped
  p-type GaAs heterostructures

abstract:
  We present a comprehensive study of the low-field magnetoresistance in carbon
doped p-type GaAs/AlGaAs heterostructures aiming at the investigation of
spin-orbit interaction effects. The following signatures of exceptionally
strong spin-orbit interactions are simultaneously observed: a beating in the
Shubnikov-de Haas oscillations, a classical positive magnetoresistance due to
the presence of the two spin-split subbands, and a weak anti-localization dip
in the magnetoresistance. The spin-orbit induced splitting of the heavy hole
subband at the Fermi level is determined to be around 30% of the total Fermi
energy. The phase coherence length of holes of around 2.5 $\mu$m at a
temperature of 70 mK, extracted from weak anti-localization measurements, is
promissing for the fabrication of phase-coherent p-type nanodevices.


title: Markov processes with product-form stationary distribution

abstract:
  We study a class of Markov processes with finite state space and continuous
time that have product form stationary distributions. We obtain a number of
examples that can generate conjectures for diffusions with inert drift.


title: Is Z^+(4430) a loosely bound molecular state?

abstract:
  Since $Z^+(4430)$ lies very close to the threshold of $D^\ast{\bar D}_1$, we
investigate whether $Z^+(4430)$ could be a loosely bound S-wave state of
$D^\ast{\bar D}_1$ or $D^\ast{\bar D}^\prime_1$ with $J^P=0^-, 1^-, 2^-$, i.e.,
a molecular state arising from the one-pion-exchange potential. The potential
from the crossed diagram is much larger than that from the diagonal scattering
diagram. With various trial wave functions, we notice that the attraction from
the one pion exchange potential alone is not strong enough to form a bound
state with realistic pionic coupling constants deduced from the decay widths of
$D_1$ and $D^\prime_1$.


title: Linear \infty-Harmonic maps between Rienmannian manifolds

abstract:
  In this paper, we give complete classifications of linear $\infty$-harmonic
maps between Euclidean and Heisenberg spaces, between Nil and Sol spaces. We
also classify all $\infty$-harmonic linear endomorphisms of Sol space and show
that there is a subgroup of $\infty$-harmonic linear automorphisms in the group
of linear automorphisms of Sol space.


title: Angular Momentum Mixing in a Non-spherical Color Superconductor

abstract:
  We study the angular momentum mixing effects in the color superconductor with
non-spherical pairing. We first clarify the concept of the angular momentum
mixing with a toy model for non-relativistic and spinless fermions. Then we
derive the gap equation for the polar phase of dense QCD by minimizing the CJT
free energy. The solution of the gap equation consists of all angular momentum
partial waves of odd parity. The corresponding free energy is found to be lower
than that reported in the literature with p-wave only.


title: Partners of Z(4430) and Productions in B Decays

abstract:
  Recently, Belle Collaboration has reported a resonant state produced in $B\to
K \pi\psi'$, which is called Z(4430). This state is charged, so it can not be
interpreted as an ordinary charmonium state. In this paper, we analyze the
octet to which this particle belongs and predict the masses of mesons in this
octet. Utilizing flavor SU(3) symmetry, we study production rates in several
kinds of B decays. The $\bar B^0\to Z_s^-\pi^+\to K^-\psi'\pi^+$ and $B^-\to
\bar Z_s^0 \pi^-\to K_S\psi'\pi^-$ decay channels, favored by
Cabibbo-Kobayashi-Maskawa (CKM) matrix elements, can have branching ratios of
${\cal O}(10^{-5})$. This large branching ratio could be observed at the
running $B$ factories to detect $Z_s$ particles containing a strange quark. We
also predict large branching ratios of the $Z$ and $Z_c$ ($\bar cc\bar c D,
D=u,d,s$) particle production rates in non-leptonic $B_c$ decays and radiative
B decays. Measurements of these decays at the ongoing $B$ factories and the
forthcoming Large Hadron Collider (LHC)-b experiments are helpful to clarify
the mysterious $Z$ particles.


title:
Three Dimensional MHD Wave Propagation and Conversion to Alfven Waves
  near the Solar Surface. I. Direct Numerical Solution

abstract:
  The efficacy of fast/slow MHD mode conversion in the surface layers of
sunspots has been demonstrated over recent years using a number of modelling
techniques, including ray theory, perturbation theory, differential eigensystem
analysis, and direct numerical simulation. These show that significant energy
may be transferred between the fast and slow modes in the neighbourhood of the
equipartition layer where the Alfven and sound speeds coincide. However, most
of the models so far have been two dimensional. In three dimensions the Alfven
wave may couple to the magneto-acoustic waves with important implications for
energy loss from helioseismic modes and for oscillations in the atmosphere
above the spot. In this paper, we carry out a numerical ``scattering
experiment'', placing an acoustic driver 4 Mm below the solar surface and
monitoring the acoustic and Alfvenic wave energy flux high in an isothermal
atmosphere placed above it. These calculations indeed show that energy
conversion to upward travelling Alfven waves can be substantial, in many cases
exceeding loss to slow (acoustic) waves. Typically, at penumbral magnetic field
strengths, the strongest Alfven fluxes are produced when the field is inclined
30-40 degrees from the vertical, with the vertical plane of wave propagation
offset from the vertical plane containing field lines by some 60-80 degrees.


title:
On relations among Dirichlet series whose coefficients are class numbers
  of binary cubic forms

abstract:
  We study the class numbers of integral binary cubic forms. For each $SL_2(Z)$
invariant lattice $L$, Shintani introduced Dirichlet series whose coefficients
are the class numbers of binary cubic forms in $L$. We classify the invariant
lattices, and investigate explicit relationships between Dirichlet series
associated with those lattices. We also study the analytic properties of the
Dirichlet series, and rewrite the functional equation in a self dual form using
the explicit relationship.


title:
A search for transiting extrasolar planet candidates in the OGLE-II
  microlens database of the galactic plane

abstract:
  In the late 1990s, the Optical Gravitational Lensing Experiment (OGLE) team
conducted the second phase of their long-term monitoring programme, OGLE-II,
which since has been superseded by OGLE-III. All the monitoring data of this
second phase, which was primarily aimed at finding microlensing events, have
recently been made public. Fields in the OGLE-II survey have typically been
observed with a cadence of once per night, over a period of a few months per
year. We investigated whether these radically differently sampled data can also
be used to search for transiting extrasolar planets, in particular in the light
of future projects such as PanSTARRS and SkyMapper, which will monitor large
fields, but mostly not at a cadence typical for transit studies. We selected
data for ~15700 stars with 13.0<I<16.0 in three OGLE-II fields towards the
galactic disc in the constellation Carina, each with 500-600 epochs of I-band
photometry. These light curves were first detrended using Sys-Rem, after which
they were searched for low amplitude transits using the Box Least Squares
algorithm. The detrending algorithm significantly decreased the scatter in the
light curves, from an average of 0.5% down to 0.2-0.3% for stars with I<15.
Several dozens of eclipsing binaries and low amplitude transits were found, of
which 13 candidates exhibit transits with such depth and duration that they are
possibly caused by an object with a radius less than twice that of Jupiter.
Eleven out of these thirteen candidates show significant ellipsoidal light
variations and are unlikely to host a transiting extrasolar planet. However,
OGLE2-TR-L9 (CAR_SC2_75679), is an excellent planet candidate comparable to the
known OGLE-III transiting planets, and deserves further follow-up observations.


title: A new approach to strong embeddings

abstract:
  We revisit strong approximation theory from a new perspective, culminating in
a proof of the Koml\'os-Major-Tusn\'ady embedding theorem for the simple random
walk. The proof is almost entirely based on a series of soft arguments and easy
inequalities. The new technique, inspired by Stein's method of normal
approximation, is applicable to any setting where Stein's method works. In
particular, one can hope to take it beyond sums of independent random
variables.


title: Anomalous Pulsars

abstract:
  Many astrophysicists believe that Anomalous X-Ray Pulsars (AXP), Soft
Gamma-Ray Repeaters (SGR), Rotational Radio Transients (RRAT), Compact Central
Objects (CCO), and X-Ray Dim Isolated Neutron Stars (XDINS) belong to different
classes of anomalous objects with neutron stars as the central bodies inducing
all their observable peculiarities. We have shown earlier (I.F.Malov and
G.Z.Machabeli, Astron. Astrophys. Trans. 25, 7, 2006) that AXPs and SGRs could
be described by the drift model in the framework of preposition on usual
properties of the central neutron star (rotation periods P ~ 0.1 - 1 sec,
surface magnetic fields B ~ 10^11 - 10^13 G). Here we shall try to show that
some differences of considered sources will be explained by their geometry
(particularly, by the angle BETA between their rotation and magnetic axes). If
BETA < 10 deg. (the aligned rotator) the drift waves at the outer layers of the
neutron star magnetosphere should play a key role in the observable
periodicity. For large values of BETA (the case of the nearly orthogonal
rotator) an accretion from the surrounding medium (for example, from the relic
disk) can cause some modulation and transient events in received radiation.


title: On time dynamics of coagulation-fragmentation processes

abstract:
  We establish a characterization of coagulation-fragmentation processes, such
that the induced birth and death processes depicting the total number of groups
at time $t\ge 0$ are time homogeneous. Based on this, we provide a
characterization of mean-field Gibbs coagulation-fragmentation models, which
extends the one derived by Hendriks et al. As a by- product of our results, the
class of solvable models is widened and a question posed by N. Berestycki and
Pitman is answered, under restriction to mean-field models.


title: CPT violations in Astrophysics and Cosmology

abstract:
  In this paper it is given a brief review of the current limits on the
magnitude of CPT and Lorentz Invariance violations, currently predicted in
connection with quantum gravity and string/M-theory, that can be derived from
astrophysical and cosmological data. Even if not completely unambiguous, these
observational tests of fundamental physics are complementary to the ones
obtained by accelerator experiments and by ground or space based direct
experiments, because potentially can access very high energies and large
distances.


title: Proofs of nonlocality without inequalities revisited

abstract:
  We discuss critically the so-called nonlocality without inequalities proofs
for bipartite quantum states, we generalize them and we analyze their relation
with the Clauser-Horne inequality.


title: Binaries among Extreme Horizontal Branch Stars in Globular Clusters

abstract:
  Following a review of our present knowledge about blue subdwarf stars in
globular clusters, we present an overview of the results of searches for close
binaries among these stars, including results previously published in the
literature and reporting recent and preliminary results of new data. Previous
investigations revealed a lack of close systems in NGC 6752, which we confirm
with new, more extensive observations. Our estimate of the close binary
fraction in this cluster is only 4%. From a review of the relevant literature,
there are indications that a low close binary fraction among extreme horizontal
branch (EHB) stars is a common feature in globular star clusters. On the other
hand, the field EHB population shows evidence of a remarkably high binary
fraction. Such a difference among globular cluster and field populations,
although not yet explained in detail on the basis of theoretical models, must
necessarily be related to different formation histories for EHB stars in the
field and in clusters. In this framework, preliminary results indicate that
close systems could be relatively common in the peculiar globular cluster NGC
2808, although the sample of studied stars is still small. This would imply
that not all clusters share the same behavior, as far as EHB star formation is
concerned. We briefly explore possible explanations for these results.


title: A rigorous analysis of high order electromagnetic invisibility cloaks

abstract:
  There is currently a great deal of interest in the invisibility cloaks
recently proposed by Pendry et al. that are based in the transformation
approach. They obtained their results using first order transformations. In
recent papers Hendi et al. and Cai et al. considered invisibility cloaks with
high order transformations. In this paper we study high order electromagnetic
invisibility cloaks in transformation media obtained by high order
transformations from general anisotropic media. We consider the case where
there is a finite number of spherical cloaks located in different points in
space. We prove that for any incident plane wave, at any frequency, the
scattered wave is identically zero. We also consider the scattering of finite
energy wave packets. We prove that the scattering matrix is the identity, i.e.,
that for any incoming wave packet the outgoing wave packet is the same as the
incoming one. This proves that the invisibility cloaks can not be detected in
any scattering experiment with electromagnetic waves in high order
transformation media, and in particular in the first order transformation media
of Pendry et al. We also prove that the high order invisibility cloaks, as well
as the first order ones, cloak passive and active devices. The cloaked objects
completely decouple from the exterior. Actually, the cloaking outside is
independent of what is inside the cloaked objects. The electromagnetic waves
inside the cloaked objects can not leave the concealed regions and viceversa,
the electromagnetic waves outside the cloaked objects can not go inside the
concealed regions. As we prove our results for media that are obtained by
transformation from general anisotropic materials, we prove that it is possible
to cloak objects inside general crystals.


title: A Schur Complement Approach to Chiral Fermions

abstract:
  Lattice chiral fermions are synonymous to the Ginsparg-Wilson relation.
Indeed, this relation is satisfied by the overlap, domain wall and perfect
action fermion kernel.
  In a recent work we have shown that it is possible to take a direct RG
approach for fermions in the presence of gauge fields. This is due to an
algebraically implicit blocking technique which yields a Schur-complementary
coarse Dirac operator. Using a Schur complement approximation which is stable
and regular, the scheme can be iterated to the fixed point.
  In this talk, we elaborate more on the direct RG approach and show how to get
highly improved chiral fermions on the coarse lattice with the gauge fields
remaining on the fine lattice. We give numerical examples in the case of
lattice QCD using QCDLAB {\tt http://phys.fshn.edu.al/qcdlab.html}


title: Comparing Pure Yang-Mills SU(2) and SU(3) Propagators

abstract:
  The infrared behavior of gluon and ghost propagators in Yang-Mills gauge
theories is of central importance for the understanding of confinement in QCD.
While analytic studies using Schwinger-Dyson equations predict the same
infrared exponents for the SU(2) and SU(3) gauge groups, lattice simulations
usually assume that the two cases are different, although their qualitative
infrared features may be the same. We carry out a comparative study of lattice
(Landau) propagators for both gauge groups. Our data were especially produced
with equivalent lattice parameters to allow a careful comparison of the two
cases.


title: On the information completeness of quantum tomograms

abstract:
  We address the problem of information completeness of quantum measuremets in
connection to quantum state tomography and with particular concern to quantum
symplectic tomography. We put forward some non-trivial situations where
informationally incomplete set of tomograms allows as well the state
reconstruction provided to have some a priori information on the state or its
dynamics. We then introduce a measure of information completeness and apply it
to symplectic quantum tomograms.


title: Differential Invariants of SL(2) and SL(3)-ACTIONS on R^2

abstract:
  The main purpose of this paper is calculation of differential invariants
which arise from prolonged actions of two Lie groups SL(2) and SL(3) on the
$n$th jet space of $R^2$. It is necessary to calculate $n$th prolonged
infenitesimal generators of the action.


title:
Applications of Thirring Model to Inhomogenous Rolling Tachyon and
  Dissipative Quantum Mechanics

abstract:
  We study the rolling tachyon and the dissipative quantum mechanics using the
Thirring model with a boundary mass. We construct a boundary state for the
dissipative quantum system in one dimension, which describes the system at the
off-critical points as well as at the critical point. Then we extend the
Thirring model with a boundary mass in order to depict the time evolution of an
unstable D-branes with one direction wrapped on a circle of radius $R$, which
is termed the inhomogeneous rolling tachyon. The analysis based on the Thirring
model shows that the time dependent evolution of the inhomogeneous tachyon is
possible only when $\frac{2}{\sqrt{3}}< R < 2$.


title: Maximum likelihood estimators and random walks in long memory models

abstract:
  We consider statistical models driven by Gaussian and non-Gaussian
self-similar processes with long memory and we construct maximum likelihood
estimators (MLE) for the drift parameter. Our approach is based on the
approximation by random walks of the driving noise. We study the asymptotic
behavior of the estimators and we give some numerical simulations to illustrate
our results.


title:
Reply to Comment on ``Time-dependent quasi-Hermitian Hamiltonians and
  the unitary quantum evolution''

abstract:
  In his fresh "Comment" (arXiv:0711.0137v1), A. Mostafazadeh reacts on my very
recent letter (arXiv:0710.5653v1) where I tried to clarify certain
misunderstandings which occurred in A. M., Phys. Lett. B \textbf{650}, 208
(2007) [arXiv:0706.1872v2, "Paper"]. As long as the "Comment" offers a new
support of the original assertions made in the "Paper", I feel obliged to
re-clarify the matter by extending my argumentation. I insist that it is
possible to escape the main conclusion of the "Paper", indeed. In particular, I
point out a gap in the new calculations in "Comment", add a few remarks on the
notation and reconfirm that the unitarity of the time-evolution DOES NOT
require the time-independence of the metric operator.


title:
The Thermal Composite Supernova Remnant Kes 27 as Viewed by CHANDRA:
  Shock Reflection from a Cavity Wall

abstract:
  We present a spatially resolved spectroscopic study of the thermal composite
supernova remnant Kes 27 with Chandra. The X-ray spectrum of Kes 27 is
characterized by K lines from Mg, Si, S, Ar, and Ca. The X-ray emitting gas is
found to be enriched in sulphur and calcium. The broadband and tri-color images
show two incomplete shell-like features in the northeastern half and brightness
fading with increasing radius in the southwest. There are over 30 unresolved
sources within the remnant. None show characteristics typical of young neutron
stars. The maximum diffuse X-ray intensity coincides with a radio bright region
along the eastern border. In general, gas in the inner region is at higher
temperature and emission is brighter than from the outer region. The gas in the
remnant appears to approach ionization equilibrium. The overall morphology can
be explained by the evolution of the remnant in an ambient medium with a
density enhancement from west to east. We suggest that the remnant was born in
a pre-existing cavity and that the inner bright emission is due to the
reflection of the initial shock from the dense cavity wall. This scenario may
provide a new candidate mechanism for the X-ray morphology of other thermal
composite supernova remnants.


title: The Mott insulator LaTiO_3 in heterostructures with SrTiO_3 is metallic

abstract:
  It is shown that LaTiO_3 in superlattices with SrTiO_3 is not a Mott
insulator but a strongly correlated metal. The tetragonal lattice geometry
imposed by the SrTiO_3 substrate leads to an increase of the Ti 3d t2g band
width and a reversal of the t2g crystal field relative to the orthorhombic bulk
geometry. Using dynamical mean field theory based on finite-temperature
multi-band exact diagonalization we show that, as a result of these effects,
local Coulomb interactions are not strong enough to induce a Mott transition in
tetragonal LaTiO_3. The metalicity of these heterostructures is therefore not
an interface property but stems from all LaTiO_3 planes.


title:
Radiative Recombination Spectra of Heavily p-Type delta-Doped Gaas/Alas
  MQWs

abstract:
  We present a study of the photoluminescence (PL) properties of heavily Be
delta-doped GaAs/AlAs multiple quantum wells measured at room and liquid
nitrogen temperatures. Possible mechanisms for photocarriers recombination are
discussed, with a particular focus on the peculiarities of the excitonic and
free carriers-acceptors PL emissions occurring below and above the Mott
metal-insulator transition. Moreover, based on a simple theoretical model, it
is found that the critical impurities concentration to observe the Mott
transition in the MQW samples exhibiting 15 nm wells width and 5 nm-thick
barrier layers is about 3 10E12 cm-2.


title: Secondary anisotropies of the CMB

abstract:
  The Cosmic Microwave Background fluctuations provide a powerful probe of the
dark ages of the universe through the imprint of the secondary anisotropies
associated with the reionisation of the universe and the growth of structure.
We review the relation between the secondary anisotropies and and the primary
anisotropies that are directly generated by quantum fluctuations in the very
early universe. The physics of secondary fluctuations is described, with
emphasis on the ionisation history and the evolution of structure. We discuss
the different signatures arising from the secondary effects in terms of their
induced temperature fluctuations, polarisation and statistics. The secondary
anisotropies are being actively pursued at present, and we review the future
and current observational status.


title:
Electrical Control of Dynamic Spin Splitting Induced by Exchange
  Interaction as Revealed by Time Resolved Kerr Rotation in a Degenerate
  Spin-Polarized Electron Gas

abstract:
  The manipulation of spin degree of freedom have been demonstrated in spin
polarized electron plasma in a heterostructure by using exchange-interaction
induced dynamic spin splitting rather than the Rashba and Dresselhaus types, as
revealed by time resolved Kerr rotation. The measured spin splitting increases
from 0.256meV to 0.559meV as the bias varies from -0.3V to -0.6V. Both the sign
switch of Kerr signal and the phase reversal of Larmor precessions have been
observed with biases, which all fit into the framework of
exchange-interaction-induced spin splitting. The electrical control of it may
provide a new effective scheme for manipulating spin-selected transport in spin
FET-like devices.


title: On the growth of structure in theories with a dynamical preferred frame

abstract:
  We study the cosmological stability of a class of theories with a dynamical
preferred frame. For a range of actions, we find cosmological solutions which
are compatible with observations of the recent history of the Universe: a
matter dominated era followed by accelerated expansion. We then study the
evolution of linear perturbations on these backgrounds and find conditions on
the parameters of the theory which allow for the growth of structure sourced by
the new degrees of freedom.


title: CC DIS at alpha_s^3 in Mellin-N and Bjorken-x spaces

abstract:
  Third-order results for the structure functions of charged-current
deep-inelastic scattering are discussed. New results for 11'th Mellin moment
for F_2,L^(nu P - nubar P) structure functions and 12'th moment for F_3^(nu P -
nubar P) are presented as well as corresponding higher Mellin moments of
differences between the respective crossing-even and -odd coefficient
functions. Approximations in Bjorken-x space for these differences obtained
with lowest five moments as well as consistency of new results with these
approximations are discussed. The 1/N_c suppression of the differences is shown
and the correction to the Paschos-Wolfenstein relation is discussed.


title: Purely Algebraic Method to Construct Toric Schemes

abstract:
  In this article, we first give some elementary proprieties of monoids and
fans, then construct a toric scheme over an arbitrary ring, from a given fan.
Using Valuative Criterion, we prove that this scheme is separated and give the
sufficient and necessary condition when it is proper. We also study the
regularity and logarithmic regularity of it. Finally we study the morphisms of
toric schemes induced by the homomorphisms of fans.


title:
Monte Carlo simulations of star clusters with primordial binaries.
  Comparison with N-body simulations and observations

abstract:
  We outline the steps needed in to calibrate the Monte Carlo code in order to
perform large scale simulations of real globular clusters. We calibrate the
results against $N$-body simulations for $N = 2500$, 10000 and for the old open
cluster M67. The calibration is done by choosing appropriate free code
parameters.


title: Interacting generalized Chaplygin gas model in non-flat universe

abstract:
  We employ the generalized Chaplygin gas of interacting dark energy to obtain
the equation of state for the generalized Chaplygin gas energy density in
non-flat universe. By choosing a negative value for $B$ we see that $w_{\rm
\Lambda}^{eff}< -1$, that corresponds to a universe dominated by phantom dark
energy.


title: Jacobi Forms of Degree One and Weil Representations

abstract:
  We discuss the notion of Jacobi forms of degree one with matrix index, we
state dimension formulas, give explicit examples, and indicate how closely
their theory is connected to the theory of invariants of Weil representations
associated to finite quadratic modules.


title: Results from multi-frequency observations of PSR B0826-34

abstract:
  We report new results obtained from multi-frequency observations of PSR
B0826-34 with the Giant Metrewave Radio Telescope (GMRT). (1) We find no
evidence of weak emission during the typical long null state of this pulsar,
simultaneously at 303 and 610 MHz, as well as individually at 157, 325, 610 and
1060 MHz at separate epochs. Our limit of non-detection is at ~ 1% or better of
the peak of the active state profile, and corresponds to ~ 2 mJy at 610 MHz.
(2) Significant correlation in the total intensity of the individual pulses
between 303 and 610 MHz is reported from the simultaneous dual frequency
observations, which is indicative of the broadband nature of the emission. We
also report correlation between total energy in the main pulse and inter-pulse
region from the high sensitivity single frequency observations at 610 and 1060
MHz. (3) Though we find the drift pattern to be very similar in the
simultaneous 303 and 610 MHz data, we observe that the drift band separation
(P2) evolves significantly between these two frequencies, and in a manner
opposite to the average profile evolution. In addition, we confirm the
dependence of P2 on pulse longitude at 303 MHz and find indications for the
same at 610 MHz. We also present results for subpulse width at different
frequencies, and as well as a function of pulse longitude. (4) As a natural
out-come of the simultaneous dual frequency observations, we obtain an accurate
DM value, equal to 52.2(6) pc/cc, for this pulsar.


title: How many latin rectangles are there?

abstract:
  Until now the problem counting Latin rectangles m x n has been solved with an
explicit formula for m = 2, 3 and 4 only. In the present paper an explicit
formula is provided for the calculation of the number of Latin rectangles for
any order m. The results attained up to now become particular cases of this new
formula. Furthermore, putting m = n, the number of Latin squares of order n can
also be obtained in an explicit form.


title: Web-based Interface in Public Cluster

abstract:
  A web-based interface dedicated for cluster computer which is publicly
accessible for free is introduced. The interface plays an important role to
enable secure public access, while providing user-friendly computational
environment for end-users and easy maintainance for administrators as well. The
whole architecture which integrates both aspects of hardware and software is
briefly explained. It is argued that the public cluster is globally a unique
approach, and could be a new kind of e-learning system especially for parallel
programming communities.


title: Searches for Physics Beyond the Standard Model at Colliders

abstract:
  All experimental measurements of particle physics today are beautifully
described by the Standard Model. However, there are good reasons to believe
that new physics may be just around the corner at the TeV energy scale. This
energy range is currently probed by the Tevatron and HERA accelerators and
selected results of searches for physics beyond the Standard Model are
presented here. No signals for new physics have been found and limits are
placed on the allowed parameter space for a variety of different particles.


title: Synchronization on complex networks with different sorts of communities

abstract:
  In this paper, inspired by the idea that many real networks are composed by
different sorts of communities, we investigate the synchronization property of
oscillators on such networks. We identify the communities by the intrinsic
frequencies probability density $g(\omega)$ of Kuramoto oscillators. That is to
say, communities in different sorts are functional different. For a network
containing two sorts of communities, when the community strength is strong,
only the oscillators in the same community synchronize. With the weakening of
the community strength, an interesting phenomenon, \emph{Community Grouping},
appears: although the global synchronization is not achieved, oscillators in
the same sort of communities will synchronize. Global synchronization will
appear with the further reducing of the community strength, and the oscillators
will rotate around the average frequency.


title: Automorphisms of Chevalley groups of types B_2 and G_2 over local rings

abstract:
  In the paper we prove that every automorphism of any adjoint Chevalley group
of types B_2 or G_2 is standard, i.e., it is a composition of the ``inner''
automorphism, ring automorphism and central automorphism.


title:
Automorphisms of the semigroup of invertible matrices with nonnegative
  elements over commutative partially ordered rings

abstract:
  Suppose that R is an ordered ring, G_n(R) is a subsemigroup of $GL_n(R)$,
consisting of all matrices with nonnegative elements. A.V. Mikhalev and M.A.
Shatalova described all automorphisms of G_n(R), where R is a linearly ordered
skewfield and n>1. E.I. Bunina and A.V. Mikhalev found all automorphisms of
G_n(R), if R is an arbitrary linearly ordered associative ring with 1/2, n>2.
In this paper we describe automorphisms of G_n(R), if R is a commutative
partially ordered ring, containing Q, n>2.


title:
Torque magnetometry study of metamagnetic transitions in single-crystal
  HoNi2B2C at T\approx 1.9 K

abstract:
  Metamagnetic transitions in single-crystal rare-earth nickel borocarbide
HoNi$_2$B$_2$C have been studied at T\approx 1.9 K with a Quantum Design torque
magnetometer. This compound is highly anisotropic with a variety of
metamagnetic states at low temperature which includes antiferromagnetic,
ferrimagnetic, non-collinear and ferromagnetic-like (saturated paramagnet)
states. The critical fields of the transitions depend crucially on the angle
$\theta$ between applied field and the easy axis [110]. Measurements of torque
along the c-axis have been made while changing the angular direction of the
magnetic field (parallel to basal tetragonal $ab$-planes) and with changing
field at fixed angle over a wide angular range. Two new phase boundaries in the
region of the non-collinear phase have been observed, and the direction of the
magnetization in this phase has been precisely determined. At low field the
antiferromagnetic phase is observed to be multidomain. In the angular range
very close to the hard axis [100] ($-6^{\circ} \lesssim\phi \lesssim
6^{\circ}$, where $\phi$ is the angle between field and the hard axis) the
magnetic behavior is found to be ``frustrated'' with a mixture of phases with
different directions of the magnetization.


title:
Hysteretic magnetotransport in p-type AlGaAs heterostructures with
  In/Zn/Au ohmic contacts

abstract:
  The two-terminal magneto-conductance of a hole gas in C-doped AlGaAs/GaAs
heterostructures with ohmic contacts consisting of alloyed In/Zn/Au displays a
pronounced hysteresis of the conductance around zero magnetic field. The
hysteresis disappears above magnetic fields of around 0.5 T and temperatures
above 300 mK. For magnetic fields below 10 mT we observe a pronounced dip in
the magneto-conductance. We tentatively discuss these experimental observations
in the light of superconductivity of the ohmic contacts.


title: Which operator generates time evolution in Quantum Mechanics?

abstract:
  We attract attention to an interesting family of quantum systems where the
generator $H_{(gen)}$ of time-evolution of wave functions is not equal to the
Hamiltonian $H$. We describe the origin of the difference $H_{(gen)}-H$ and
interpret it as a carrier of a compressed information about the other relevant
observables.


title:
Detection of strong activity in the eclipsing binary brown dwarf
  2MASSJ05352184-0546085 - A possible explanation for the temperature reversal

abstract:
  We show high resolution spectra of the eclipsing brown dwarf binary
2MASSJ05352184-0546085 taken at the two opposite radial velocity maxima.
Comparisons of the TiO bands to model and template spectra are fully consistent
with the temperatures previously derived for this system. In particular, the
reversal of temperatures with mass - in which the higher-mass primary is cooler
than its companion - is confirmed. We measure the projected rotation velocities
of the compononents; the primary is rotating at least twice as rapidly as the
secondary. At the two radial velocity maxima, Halpha emission lines of both
components stick out to either sides of the Halpha central wavelength, which is
dominated by nebula emission. This enables us to model the individual Halpha
lines of the primary and the secondary. We find that the Halpha emission from
the primary is at least 7 times stronger than the emission from the secondary.
We conclude that the temperature reversal is very likely due to strong magnetic
fields inhibiting convection on the primary.


title:
A new wavelet-based approach for the automated treatment of large sets
  of lunar occultation data

abstract:
  The introduction of infrared arrays for lunar occultations (LO) work and the
improvement of predictions based on new deep IR catalogues have resulted in a
large increase in the number of observable occultations.
  We provide the means for an automated reduction of large sets of LO data.
This frees the user from the tedious task of estimating first-guess parameters
for the fit of each LO lightcurve. At the end of the process, ready-made plots
and statistics enable the user to identify sources which appear to be resolved
or binary and to initiate their detailed interactive analysis.
  The pipeline is tailored to array data, including the extraction of the
lightcurves from FITS cubes. Because of its robustness and efficiency, the
wavelet transform has been chosen to compute the initial guess of the
parameters of the lightcurve fit.
  We illustrate and discuss our automatic reduction pipeline by analyzing a
large volume of novel occultation data recorded at Calar Alto Observatory. The
automated pipeline package is available from the authors.


title: Spreadsheet Engineering: A Research Framework

abstract:
  Spreadsheet engineering adapts the lessons of software engineering to
spreadsheets, providing eight principles as a framework for organizing
spreadsheet programming recommendations. Spreadsheets raise issues inadequately
addressed by software engineering. Spreadsheets are a powerful modeling
language, allowing strategic rapid model change, and enabling exploratory
modeling. Spreadsheets users learn slowly with experience because they focus on
the problem domain not programming. The heterogeneity of spreadsheet users
requires a taxonomy to guide recommendations. Deployment of best practices is
difficult and merits research.


title:
A Positive Mass Theorem on Asymptotically Hyperbolic Manifolds with
  Corners Along a Hypersurface

abstract:
  In this paper we take an approach similar to that in [M] to establish a
positive mass theorem for asymptotically hyperbolic spin manifolds admitting
corners along a hypersurface. The main analysis uses an integral representation
of a solution to a perturbed eigenfunction equation to obtain an asymptotic
expansion of the solution in the right order. This allows us to understand the
change of the mass aspect of a conformal change of asymptotically hyperbolic
metrics.


title: Umkehr Maps

abstract:
  In this note we study umkehr maps in generalized (co)homology theories
arising from the Pontrjagin-Thom construction, from integrating along fibers,
pushforward homomorphisms, and other similar constructions. We consider the
basic properties of these constructions and develop axioms which any umkehr
homomorphism must satisfy. We use a version of Brown representability to show
that these axioms completely characterize these homomorphisms, and a resulting
uniqueness theorem follows. Finally, motivated by constructions in string
topology, we extend this axiomatic treatment of umkehr homomorphisms to a
fiberwise setting.


title: Dynamical Implications of Viral Tiling Theory

abstract:
  The Caspar-Klug classification of viruses whose protein shell, called viral
capsid, exhibits icosahedral symmetry, has recently been extended to
incorporate viruses whose capsid proteins are exclusively organised in
pentamers. The approach, named `Viral Tiling Theory', is inspired by the theory
of quasicrystals, where aperiodic Penrose tilings enjoy 5-fold and 10-fold
local symmetries. This paper analyzes the extent to which this classification
approach informs dynamical properties of the viral capsids, in particular the
pattern of Raman active modes of vibrations, which can be observed
experimentally.


title: Statistical Physics and Dynamical Systems: Models of Phase Transitions

abstract:
  This paper explores the connection between dynamical system properties and
statistical physics of ensembles of such systems. Simple models are used to
give novel phase transitions; particularly for finite N particle systems with
many physically interesting examples.


title: Conformal invariance of chiral edge theories

abstract:
  The low-energy effective quantum field theory of the edge excitations of a
fully-gapped bulk topological phase corresponding to a local interaction
Hamiltonian must be local and unitary. Here it is shown that whenever all the
edge excitations propagate in the same direction with the same velocity, it is
a conformal field theory. In particular, this is the case in the quantum Hall
effect for model "special Hamiltonians", for which the ground state, quasihole,
and edge excitations can be found exactly as zero-energy eigenstates, provided
the spectrum in the interior of the system is fully gapped. In addition, other
conserved quantities in the bulk, such as particle number and spin, lead to
affine Lie algebra symmetries in the edge theory. Applying the arguments to
some trial wavefunctions related to non-unitary conformal field theories, it is
argued that the Gaffnian state and an infinite number of others cannot describe
a gapped topological phase because the numbers of edge excitations do not match
any unitary conformal field theory.


title:
Wall rational functions and Khrushchev's formula for orthogonal rational
  functions

abstract:
  We prove that the Nevalinna-Pick algorithm provides different homeomorphisms
between certain topological spaces of measures, analytic functions and
sequences of complex numbers. This algorithm also yields a continued fraction
expansion of every Schur function, whose approximants are identified. The
approximants are quotients of rational functions which can be understood as the
rational analogs of the Wall polynomials. The properties of these Wall rational
functions and the corresponding approximants are studied. The above results
permit us to obtain a Khrushchev's formula for orthogonal rational functions.
An introduction to the convergence of the Wall approximants in the
indeterminate case is also presented.


title:
The Arecibo Legacy Fast ALFA Survey: V. HI Source Catalog of the
  Anti-Virgo Region at dec=27 degrees

abstract:
  We present a second catalog of HI sources detected in the Arecibo Legacy Fast
ALFA Survey. We report 488 detections over 135 square degrees, within the
region of the sky having 22h<RA<03h and +26deg<Dec<+28deg. We present here the
detections that have either (a) S/N>6.5, where the reliability of the catalog
is better than 95% or (b) 5.0<S/N<6.5 and a previously measured redshift that
corroborates our detection. Of the 488 objects presented here, 49 are High
Velocity Clouds or clumps thereof with negative heliocentric recession
velocities. These clouds are mostly very compact and isolated, while some of
them are associated with large features such as Wright's Cloud or the northern
extension of the Magellanic Stream. The remaining 439 candidate detections are
identified as extragalactic objects and have all been matched with optical
counterparts. Five of the six galaxies detected with M(HI)<10^7.5 solar masses
are satellites of either the NGC672/IC1727 nearby galaxy pair or their
neighboring dwarf irregular galaxy NGC784. The data of this catalog release
include a slice through the Pisces-Perseus foreground void, a large nearby
underdensity of galaxies. We report no detections within the void, where our
catalog is complete for systems with HI masses of 10^8 solar masses. Gas-rich,
optically-dark galaxies do not seem to constitute an important void population,
and therefore do not suffice at producing a viable solution to the void
phenomenon.


title: The Pontrjagin-Hopf invariants for Sobolev maps

abstract:
  Subtle issues arise when extending homotopy invariants to spaces of functions
having little regularity, e.g., Sobolev spaces containing discontinuous
functions. Sometimes it is not possible to extend the invariant at all, and
sometimes, even when the formulas defining the invariants make sense, they may
not have expected properties (e.g., there are maps having non-integral degree).
  In this paper we define a complete set of homotopy invariants for maps from
3-manifolds to the 2-sphere and show that these invariants extend to finite
Faddeev energy maps and maps in suitable Sobolev spaces. For smooth maps, our
description is proved to be equivalent to Pontrjagin's original homotopy
classification from the 1930's. We further show that for the finite energy maps
the invariants take on exactly the same values as for smooth maps. We include
applications to the Faddeev model.
  The techniques that we use would also apply to many more problems and/or
other functionals. We have tried to make the paper accessible to analysts,
geometers and mathematical physicists.


title:
High Transverse Momentum Hadron Spectra at sqrt{s_{NN}}=17.3 GeV, in
  Pb+Pb and p+p Collisions

abstract:
  Transverse momentum spectra up to 4.5 GeV/c around midrapidity of pi^{+/-},
p, pbar, K^{+/-} in Pb+Pb reactions were measured at sqrt{s_{NN}}=17.3 GeV by
the CERN-NA49 experiment. The nuclear modification factors R_{AA} for pi^{+/-}
and R_{CP} for pi^{+/-},p,pbar,K^{+/-} were extracted and are compared to RHIC
results at sqrt{s_{NN}}=200 GeV. The modification factor R_{AA} shows a rapid
increase with transverse momentum in the covered region. This indicates that
the Cronin effect is the dominating effect in our energy range. The
modification factor R_{CP}, in which the contribution of the Cronin effect is
reduced, shows a saturation well below unity in the pi^{+/-} channel. The
extracted R_{CP} values follow the 200 GeV RHIC results closely in the
available transverse momentum range, except for pi^{+/-} above 2.5 GeV/c
transverse momentum. There the measured suppression is smaller than that
observed at RHIC.