title: Probing N=4 SYM With Surface Operators

abstract:
  In this paper we study surface operators in N=4 supersymmetric Yang-Mills
theory. We compute surface operator observables, such as the expectation value
of surface operators, the correlation function of surface operators with local
operators, and the correlation function of surface operators with Wilson and 't
Hooft loops. The calculations are performed using three different realizations
of surface operators, corresponding respectively to the gauge theory path
integral definition, the probe brane description in AdS_5xS^5 and the
"bubbling'' supergravity description of surface operators. We find remarkable
agreement between the different calculations performed using the three
different realizations.


title:
On the New Model of Non-Fermi Liquid for High Temperature
  Superconductivity

abstract:
  The importance of introducing the SO(5) singlet into the new novel model of
non-Fermi liquid proposed by LeClair and collaborators is pointed out. This
SO(5) singlet order parameter leads to a phase transition between the normal
metal and the pseudogap region in the phase diagram for the anti-ferromagnetic
(AF) phase and the (d-wave) superconducting (SC) phase. A non-zero value for
this order can increase substantially the critical temperature of the SC
transition.


title: Bulk viscosity and spectral functions in QCD

abstract:
  We examine the behavior of the spectral function for the trace of the stress
tensor in QCD in the two regimes where it is possible to make analytical
progress; weak coupling, and close to a second order QCD phase transition. We
determine the behavior of the bulk viscosity in each regime. We discuss the
problem of analytic continuation of the (lattice) Euclidean correlation
function to determine the spectral function. In each case the spectral function
has a narrow peak at small frequency; its shape would be challenging to extract
accurately from lattice data with error bars.


title: Signals of Doubly-Charged Higgsinos at the CERN Large Hadron Collider

abstract:
  Several supersymmetric models with extended gauge structures, motivated by
either grand unification or by neutrino mass generation, predict light
doubly-charged Higgsinos. In this work we study productions and decays of
doubly-charged Higgsinos present in left-right supersymmetric models, and show
that they invariably lead to novel collider signals not found in the minimal
supersymmetric model (MSSM) or in any of its extensions motivated by the \mu
problem or even in extra dimensional theories. We investigate their distinctive
signatures at the Large Hadron Collider (LHC) in both pair-- and
single--production modes, and show that they are powerful tools in determining
the underlying model via the measurements at the LHC experiments.


title:
$p_{x}+ip_{y}$ superfluid from s-wave interactions of fermionic cold
  atoms

abstract:
  Two-dimensional ($p_{x}+ip_{y}$) superfluids/superconductors offer a
playground for studying intriguing physics such as quantum teleportation,
non-Abelian statistics, and topological quantum computation. Creating such a
superfluid in cold fermionic atom optical traps using p-wave Feshbach resonance
is turning out to be challenging. Here we propose a method to create a
$p_{x}+ip_{y}$ superfluid directly from an s-wave interaction making use of a
topological Berry phase, which can be artificially generated. We discuss ways
to detect the spontaneous Hall mass current, which acts as a diagnostic for the
chiral p-wave superfluid.


title: Crossed products and cleft extensions for coquasi-Hopf algebras

abstract:
  The notion of crossed product by a coquasi-bialgebra H is introduced and
studied. The resulting crossed product is an algebra in the monoidal category
of right H-comodules. We give an interpretation of the crossed product as an
action of a monoidal category. In particular, necessary and sufficient
conditions for two crossed products to be equivalent are provided. Then, two
structure theorems for coquasi Hopf modules are given. First, these are
relative Hopf modules over the crossed product. Second, the category of
coquasi-Hopf modules is trivial, namely equivalent to the category of modules
over the starting associative algebra. In connection the crossed product, we
recall the notion of a cleft extension over a coquasi-Hopf algebra. A Morita
context of Hom spaces is constructed in order to explain these extensions,
which are shown to be equivalent with crossed product with invertible cocycle.
At the end, we give a complete description of all cleft extensions by the
non-trivial coquasi-Hopf algebras of dimension two and three.


title: MAMBO Mapping of Spitzer c2d Small Clouds and Cores

abstract:
  AIMS: To study the structure of nearby (< 500 pc) dense starless and
star-forming cores with the particular goal to identify and understand
evolutionary trends in core properties, and to explore the nature of Very Low
Luminosity Objects (< 0.1 L_sun; VeLLOs). METHODS: Using the MAMBO bolometer
array, we create maps unusually sensitive to faint (few mJy per beam) extended
(approx. 5 arcmin) thermal dust continuum emission at 1.2 mm wavelength.
Complementary information on embedded stars is obtained from Spitzer, IRAS, and
2MASS. RESULTS: Our maps are very rich in structure, and we characterize
extended emission features (``subcores'') and compact intensity peaks in our
data separately to pay attention to this complexity. We derive, e.g., sizes,
masses, and aspect ratios for the subcores, as well as column densities and
related properties for the peaks. Combination with archival infrared data then
enables the derivation of bolometric luminosities and temperatures, as well as
envelope masses, for the young embedded stars. CONCLUSIONS: (abridged) Starless
and star-forming cores occupy the same parameter space in many core properties;
a picture of dense core evolution in which any dense core begins to actively
form stars once it exceeds some fixed limit in, e.g., mass, density, or both,
is inconsistent with our data. Comparison of various evolutionary indicators
for young stellar objects in our sample (e.g., bolometric temperatures) reveals
inconsistencies between some of them, possibly suggesting a revision of some of
these indicators.


title:
The Structure of Classical Bulges And Pseudobulges: The Link Between
  Pseudobulges And Sersic Index

abstract:
  In this paper we study the properties of pseudobulges (bulges that appear
similar to disk galaxies) and classical bulges (bulges which appear similar to
E-type galaxies) in bulge-disk decompositions. We show that the distribution of
bulge Sersic indices is bimodal, and this bimodality correlates with the
morphology of the bulge. Pseudobulges have n<2 and classical bulges have n>2
with little overlap. Also, pseudobulges do not follow the correlations of
Sersic index with structural parameters or the photometric projections of the
fundamental plane in the same way as classical bulges and elliptical galaxies
do. We find that pseudobulges are systematically flatter than classical bulges
and thus more disk-like in both their morphology and shape. We do not find
significant differences between different bulge morphologies that we are
collectively calling pseudobulges (nuclear spirals, nuclear rings, nuclear
bars, and nuclear patchiness) appear to behave similarly in all parameter
correlations. In Sersic index, flattening, and bulge-to-total ratio, the
distinction appears to be between classical bulges and pseudobulges, not
between different pseudobulge morphologies. The Sersic index of the
pseudobulges does not correlate with B/T, in contrast to classical bulges.
Also, the half-light radius of the pseudobulge correlates with the scale length
of the disk; this is not the case for classical bulges. The correlation of
Sersic index and scale lengths with bulge morphology suggests that secular
evolution is creating pseudobulges with low-Sersic index, and that other
processes (e.g. major mergers) are responsible for the higher Sersic index in
classical bulges and elliptical galaxies.


title:
The Experimental Probe of Inflationary Cosmology (EPIC): A Mission
  Concept Study for NASA's Einstein Inflation Probe

abstract:
  This is the Phase 1 Report on the Experimental Probe of Inflationary
Cosmology (EPIC), a mission concept study for NASA's Einstein Inflation Probe.
When we began our study we sought to answer five fundamental implementation
questions: 1) can foregrounds be measured and subtracted to a sufficiently low
level?; 2) can systematic errors be controlled?; 3) can we develop optics with
sufficiently large throughput, low polarization, and frequency coverage from 30
to 300 GHz?; 4) is there a technical path to realizing the sensitivity and
systematic error requirements?; and 5) what are the specific mission
architecture parameters, including cost? Detailed answers to these questions
are contained in this report. Currently in Phase 2, we are exploring a mission
concept targeting a ~2m aperture, in between the two options described in the
current report with a small (~30 cm) and large (~4m) missions.


title: An Orthogonal Test of the L-Functions Ratios Conjecture

abstract:
  We test the predictions of the L-functions Ratios Conjecture for the family
of cuspidal newforms of weight k and level N, with either k fixed and N --> oo
through the primes or N=1 and k --> oo. We study the main and lower order terms
in the 1-level density. We provide evidence for the Ratios Conjecture by
computing and confirming its predictions up to a power savings in the family's
cardinality, at least for test functions whose Fourier transforms are supported
in (-2, 2). We do this both for the weighted and unweighted 1-level density
(where in the weighted case we use the Petersson weights), thus showing that
either formulation may be used. These two 1-level densities differ by a term of
size 1 / log(k^2 N). Finally, we show that there is another way of extending
the sums arising in the Ratios Conjecture, leading to a different answer
(although the answer is such a lower order term that it is hopeless to observe
which is correct).


title:
Far Ultraviolet Spectroscopic Explorer Spectroscopy of the Nova-like BB
  Doradus

abstract:
  We present an analysis of the Far Ultraviolet Spectroscopic Explorer
({\it{FUSE}}) spectra of the little-known southern nova-like BB Doradus. The
spectrum was obtained as part of our Cycle 8 {\it FUSE} survey of high
declination nova-like stars.
  The FUSE spectrum of BB Dor, observed in a high state, is modeled with an
accretion disk with a very low inclination (possibly lower than 10deg).
Assuming an average WD mass of 0.8 solar leads to a mass accretion rate of
1.E-9 Solar mass/year and a distance of the order of 650 pc, consistent with
the extremely low galactic reddening in its direction. The spectrum presents
some broad and deep silicon and sulfur absorption lines, indicating that these
elements are over-abundant by 3 and 20 times solar, respectively.


title: Kaluza-Klein Dark Matter: Direct Detection vis-a-vis LHC

abstract:
  We explore the phenomenology of Kaluza-Klein (KK) dark matter in very general
models with universal extra dimensions (UEDs), emphasizing the complementarity
between high-energy colliders and dark matter direct detection experiments. In
models with relatively small mass splittings between the dark matter candidate
and the rest of the (colored) spectrum, the collider sensitivity is diminished,
but direct detection rates are enhanced. UEDs provide a natural framework for
such mass degeneracies. We consider both 5-dimensional and 6-dimensional
non-minimal UED models, and discuss the detection prospects for various KK dark
matter candidates: the KK photon $\gamma_1$, the KK $Z$-boson $Z_1$, the KK
Higgs boson $H_1$ and the spinless KK photon $\gamma_H$. We combine collider
limits such as electroweak precision data and expected LHC reach, with
cosmological constraints from WMAP, and the sensitivity of current or planned
direct detection experiments. Allowing for general mass splittings, we show
that neither colliders, nor direct detection experiments by themselves can
explore all of the relevant KK dark matter parameter space. Nevertheless, they
probe different parameter space regions, and the combination of the two types
of constraints can be quite powerful. For example, in the case of $\gamma_1$ in
5D UEDs the relevant parameter space will be almost completely covered by the
combined LHC and direct detection sensitivities expected in the near future.


title: Managing Critical Spreadsheets in a Compliant Environment

abstract:
  The use of uncontrolled financial spreadsheets can expose organizations to
unacceptable business and compliance risks, including errors in the financial
reporting process, spreadsheet misuse and fraud, or even significant
operational errors. These risks have been well documented and thoroughly
researched. With the advent of regulatory mandates such as SOX 404 and FDICIA
in the U.S., and MiFID, Basel II and Combined Code in the UK and Europe,
leading tax and audit firms are now recommending that organizations automate
their internal controls over critical spreadsheets and other end-user computing
applications, including Microsoft Access databases. At a minimum, auditors
mandate version control, change control and access control for operational
spreadsheets, with more advanced controls for critical financial spreadsheets.
This paper summarises the key issues regarding the establishment and
maintenance of control of Business Critical spreadsheets.


title: Pauli spin blockade in carbon nanotube double quantum dots

abstract:
  We report Pauli spin blockade in an impurity defined carbon nanotube double
quantum dot. We observe a pronounced current suppression for negative
source-drain bias voltages which is investigated for both symmetric and
asymmetric coupling of the quantum dots to the leads. The measured differential
conductance agrees well with a theoretical model of a double quantum dot system
in the spin-blockade regime which allows us to estimate the occupation
probabilities of the relevant singlet and triplet states. This work shows that
effective spin-to-charge conversion in nanotube quantum dots is feasible and
opens the possibility of single-spin readout in a material that is not limited
by hyperfine interaction with nuclear spins.


title: Latency in local, two-dimensional, fault-tolerant quantum computing

abstract:
  We analyze the latency of fault-tolerant quantum computing based on the
9-qubit Bacon-Shor code using a local, two-dimensional architecture. We embed
the data qubits in a 7 by 7 array of physical qubits, where the extra qubits
are used for ancilla preparation and qubit transportation by means of a SWAP
chain. The latency is reduced with respect to a similar implementation using
Steane's 7-qubit code (K. M. Svore, D. P. DiVincenzo, and B. M. Terhal, Quantum
Information & Computation {\bf 7}, 297 (2007)). Furthermore, the error
threshold is also improved to $2.02 \times 10^{-5}$, when memory errors are
taken to be one tenth of the gate error rates.


title:
Cosmological Shocks in Eulerian Simulations: Main Properties and Cosmic
  Rays Acceleration

abstract:
  Aims: morpholgies, number and energy distributions of Cosmological Shock
Waves from a set of ENZO cosmological simulations are produced, along with a
study of the connection with Cosmic Rays processes in different environments.
Method: we perform cosmological simulations with the public release of the PPM
code ENZO, adopt a simple and physically motivated numerical setup to follow
the evolution of cosmic structures at the resolution of 125kpc per cell, and
characterise shocks with a new post processing scheme. Results: we estimate the
efficency of the acceleration of Cosmic Ray particles and present the first
comparison of our results with existing limits from observations of galaxy
clusters.


title: Dust Emission from the Perseus Molecular Cloud

abstract:
  Using far-infrared emission maps taken by IRAS and Spitzer and a
near-infrared extinction map derived from 2MASS data, we have made dust
temperature and column density maps of the Perseus molecular cloud. We show
that the emission from transiently heated very small grains and the big grain
dust emissivity vary as a function of extinction and dust temperature, with
higher dust emissivities for colder grains. This variable emissivity can not be
explained by temperature gradients along the line of sight or by noise in the
emission maps, but is consistent with grain growth in the higher density and
lower temperature regions. By accounting for the variations in the dust
emissivity and VSG emission, we are able to map the temperature and column
density of a nearby molecular cloud with better accuracy than has previously
been possible.


title:
Extremal N=(2,2) 2D Conformal Field Theories and Constraints of
  Modularity

abstract:
  We explore the constraints on the spectrum of primary fields implied by
modularity of the elliptic genus of N=(2,2) 2D CFT's. We show that such
constraints have nontrivial implications for the existence of "extremal"
N=(2,2) conformal field theories. Applications to AdS3 supergravity and flux
compactifications are addressed.


title: Towards a New Proof of Anderson Localization

abstract:
  The wave function of a non-relativistic particle in a periodic potential
admits oscillatory solutions, the Bloch waves. In the presence of a random
noise contribution to the potential the wave function is localized. We outline
a new proof of this Anderson localization phenomenon in one spatial dimension,
extending the classical result to the case of a periodic background potential.
The proof makes use of techniques previously developed to study the effects of
noise on reheating in inflationary cosmology, employing methods of random
matrix theory.

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


title: A Structured Methodology for Spreadsheet Modelling

abstract:
  In this paper, we discuss the problem of the software engineering of a class
of business spreadsheet models. A methodology for structured software
development is proposed, which is based on structured analysis of data,
represented as Jackson diagrams. It is shown that this analysis allows a
straightforward modularisation, and that individual modules may be represented
with indentation in the block-structured form of structured programs. The
benefits of structured format are discussed, in terms of comprehensibility,
ease of maintenance, and reduction in errors. The capability of the methodology
to provide a modular overview in the model is described, and examples are
given. The potential for a reverse-engineering tool, to transform existing
spreadsheet models is discussed.


title: Building Financial Accuracy into Spreadsheets

abstract:
  Students learning how to apply spreadsheets to accounting problems are not
always well served by the built-in financial functions. Problems can arise
because of differences between UK and US practice, through anomalies in the
functions themselves, and because the promptings of Wizards' engender an
attitude of filling in the blanks on the screen, and hoping for the best. Some
examples of these problems are described, and suggestions are presented for
ways of improving the situation. Principally, it is suggested that spreadsheet
prompts and 'Help' screens should offer integrated guidance, covering some
aspects of financial practice, as well as matters of spreadsheet technique.


title: Best subspace tensor approximations

abstract:
  In many applications such as data compression, imaging or genomic data
analysis, it is important to approximate a given tensor by a tensor that is
sparsely representable. For matrices, i.e. 2-tensors, such a representation can
be obtained via the singular value decomposition which allows to compute the
best rank $k$ approximations. For $t$-tensors with $t>2$ many generalizations
of the singular value decomposition have been proposed to obtain low tensor
rank decompositions. In this paper we will present a different approach which
is based on best subspace approximations, which present an alternative
generalization of the singular value decomposition to tensors.


title:
Ergodic Theory and Visualization I: Mesochronic Plots for Visualization
  of Ergodic Partition and Invariant Sets

abstract:
  We present a computational study of a visualization method for invariant sets
based on ergodic partition theory, first proposed in [1,2]. The algorithms for
computation of the time averages of observables on phase space are developed
and used to provide an approximation of the ergodic partition of the phase
space. We term the graphical representation of this approximation - based on
time averages of observables - a Mesochronic Plot (from Greek: \textit{meso} -
mean, \textit{chronos} - time}. The method is useful for identifying
low-dimensional projections (e.g. two-dimensional slices) of invariant
structures in phase spaces of dimensionality bigger than two. We also introduce
the concept of the ergodic quotient space, obtained by assigning a point to
every ergodic set, and provide an embedding method whose graphical
representation we call the Mesochronic Scatter Plot (MSP). We use the Chirikov
standard map as a well-known and dynamically rich example in order to
illustrate the implementation of our methods. In addition, we expose
applications to other higher dimensional maps such as the Fro\'eschle map for
which we utilize our methods to analyze merging of resonances and, the
three-dimensional Extended standard map for which we study the conjecture on
its ergodicity [3]. We extend the study in our next paper [4] by investigating
the visualization of periodic sets using harmonic time averages. Both of these
methods are related to eigenspace structure of the Koopman operator.


title: Unitary Braid Representations with Finite Image

abstract:
  We characterize unitary representations of braid groups $B_n$ of degree
linear in $n$ and finite images of such representations of degree exponential
in $n$.


title:
Are Self-explaining and Coached Problem Solving More Effective When Done
  by Pairs of Students Than Alone?

abstract:
  Although cognitive science has discovered several methods for increasing the
learning of complex skills, such as physics problem solving, detailed
examination of verbal protocols suggests there is still room for improvement.
Basically, students do not always apply the meta-cognitive strategies that the
instruction invites. For instance, when prompted to self-explain, students may
still choose to not explain. We conjecture that most students know which
meta-cognitive strategies are good and bad. When they work in pairs, they are
more likely to choose the good strategies. We hypothesize that social
accountability improves meta-cognitive strategy choice, which thereby improves
learning. Our experiment compared individuals and pairs learning from
state-of-the-art instruction. The results suggest that the dyads solved more
problems and requested fewer hints during problem solving than individuals. We
also discovered a new form of self-explanation, wherein students generate
explanations to account for the differences between their solutions and the
instructor's.


title: Classification of Spreadsheet Errors

abstract:
  This paper describes a framework for a systematic classification of
spreadsheet errors. This classification or taxonomy of errors is aimed at
facilitating analysis and comprehension of the different types of spreadsheet
errors. The taxonomy is an outcome of an investigation of the widespread
problem of spreadsheet errors and an analysis of specific types of these
errors. This paper contains a description of the various elements and
categories of the classification and is supported by appropriate examples.


title:
Upper limits on the diffuse supernova neutrino flux from the
  SuperKamiokande data

abstract:
  We analyze the 1496 days of SuperKamiokande data to put limits on the nue,
anti-nue, numu + nutau and anti-numu + anti-nutau components of the diffuse
flux of supernova neutrinos, in different energy intervals and for different
neutrino energy spectra. By considering the presence of only one component at a
time, we find the following bounds at 90% C.L. and for neutrino energy E>19.3$
MeV: Phi_{nue}<73.3-154 cm^-2 s^-1, Phi_{anti-nue} <1.4-1.9 cm^-2 s^-1,
Phi_{numu+nutau} <(1.0-1.4) 10^3 cm^-2 s^-1, and Phi_{anti-numu+ anti-nutau}
<(1.3-1.8) 10^3 cm^-2 s^-1, where the intervals account for varying the
neutrino spectrum. In the interval E = 22.9 - 36.9 MeV, we find Phi_{nue}<39-54
cm^-2 s^-1, which improves on the existing limit from SNO in the same energy
window. Our results for numu + nutau and anti-numu + anti-nutau improve by
about four orders of magnitude over the previous best constraints from LSD.


title: Chains of distributions, hierarchical Bayesian models and Benford's Law

abstract:
  Kossovsky recently conjectured that the distribution of leading digits of a
chain of probability distributions converges to Benford's law as the length of
the chain grows. We prove his conjecture in many cases, and provide an
interpretation in terms of products of independent random variables and a
central limit theorem. An interesting consequence is that in hierarchical
Bayesian models priors tend to satisfy Benford's Law as the number of levels of
the hierarchy increases, which allows us to develop some simple tests (based on
Benford's law) to test proposed models. We give explicit formulas for the error
terms as sums of Mellin transforms, which converges extremely rapidly as the
number of terms in the chain grows. We may interpret our results as showing
that certain Markov chain Monte Carlo processes are rapidly mixing to Benford's
law.


title:
Some Bounds for ramification of $p^n$-torsion semi-stable
  representations

abstract:
  Let p be an odd prime, K a finite extension of Q_p, G=Gal(\bar K/K) the
Galois group and e=e(K/Q_p) the ramification index. Suppose T is a p^n torsion
representation such that T is isomorphic to a quotient of two G-stable
Z_p-lattices in a semi-stable representation with Hodge-Tate weights in
{0,...,r}. We prove that there exists a constant \mu explicitly depending on n,
e and r such that the upper numbering ramification group G^{(\mu)} acts on T
trivially.


title:
Measurement of the Open Charm Cross-Section in 200 GeV Heavy-Ion
  Collisions at STAR

abstract:
  We report on measurements of open charm production through both hadronic and
semi-leptonic decay channels in $\sqrt{s_{NN}}$ = 200 GeV heavy ion collision
at the STAR experiment at RHIC. We compare experimental results to theoretical
predictions from pQCD. The open charm $R_{AA}$ is also presented as evidence of
possible medium-induced energy loss.


title: Vector Field Models of Inflation and Dark Energy

abstract:
  We consider several new classes of viable vector field alternatives to the
inflaton and quintessence scalar fields. Spatial vector fields are shown to be
compatible with the cosmological anisotropy bounds if only slightly displaced
from the potential minimum while dominant, or if driving an anisotropic
expansion with nearly vanishing quadropole today. The Bianchi I model with a
spatial field and an isotropic fluid is studied as a dynamical system, and
several types of scaling solutions are found. On the other hand, time-like
fields are automatically compatible with large-scale isotropy. We show that
they can be dynamically important if non-minimal gravity couplings are taken
into account. As an example, we reconstruct a vector-Gauss-Bonnet model which
generates the concordance model acceleration at late times and supports an
inflationary epoch at high curvatures. The evolution of vortical perturbations
is considered.


title: Photometric Survey for Stellar Clusters in the Outer Part of M33

abstract:
  We present a catalog of 4780 extended sources from the outer field of M33.
The catalog includes 73 previously identified clusters or planetary nebulae,
1153 likely background galaxies, and 3554 new candidate stellar clusters. The
survey is based on deep ground-based images obtained with the MegaCam
instrument on the CFHT telescope. We provide g'r'i' photometry for detected
objects as well as estimates of the FWHM and ellipticity of their profiles. The
sample includes 122 new, relatively bright, likely globular clusters. Follow-up
observations of fainter candidates from our list may extend the faint-end of
the observed luminosity function of globular clusters in M33 by up to 3
magnitudes. The catalog includes several cluster candidates located in the
outskirts of the galaxy. These objects are promising targets for deep
photometry with the HST. We present a color-magnitude diagram for one detected
object, showing that it is an extended and low-surface-brightness old cluster
located at an angular distance of 27' from the center of M33.


title: Capillary filling in patterned channels

abstract:
  We show how the capillary filling of microchannels is affected by posts or
ridges on the sides of the channels. Ridges perpendicular to the flow direction
introduce contact line pinning which slows, or sometimes prevents, filling;
whereas ridges parallel to the flow provide extra surface which may enhances
filling. Patterning the microchannel surface with square posts has little
effect on the ability of a channel to fill for equilibrium contact angle
$\theta_e \lesssim 30^{\mathrm{o}}$. For $\theta_e \gtrsim 60^{\mathrm{o}}$,
however, even a small number of posts can pin the advancing liquid front.


title:
The bright galaxy population of five medium redshift clusters. I.
  Color-Magnitude Relation, Blue Fractions and Visual Morphology

abstract:
  Using data of five clusters of galaxies within the redshift range 0.15 $\leq$
z $\leq$ 0.25, imaged with the Nordic Optical Telescope (NOT) in the central
$\approx$ 1 Mpc$^2$ in very good seeing conditions, we have performed an
exhaustive inspection of their bright galaxy population. That range of
redshift, where only a small amount of data with the required resolution and
quality is available, is particularly important for the understanding of the
formation and evolution of clusters of galaxies. We have inspected the
color-magnitude relation (CMR) for those clusters and measured the blue
fraction of galaxies in their cores to check for evidence of evolution as found
in other works. Moreover, the visual classification of the galaxy morphology
has been performed and the morphology-radius relation has been examined We have
not found signs of evolution neither in the slope of the CMR nor in the blue
fraction of galaxies. A diversity of situations regarding those parameters and
in the morphological mixing has been noticed, with two out of five clusters
containing a dominant late-type core population. The cluster A1878 stands out
as some of its properties differ from those of the other clusters in the
sample.
  No clear signs of evolution appear in our analysis. The data support the view
that the morphology and the stellar content of the galaxies in our clusters
have been already settled at z $\sim$ 0.2. Only the fraction of interacting
galaxies in the clusters appear to be larger than in clusters like Coma
although the number of clusters in the sample is small to give a definitive
conclusion.


title:
On cosmological observables in a swiss-cheese universe (Conference
  proceeding)

abstract:
  By means of a toy Swiss-cheese cosmological model we will discuss how to set
up and carry out in a physically meaningful way the idea of back-reaction,
according to which dark energy could be an effective source. We will follow two
distinct approaches. One is focused on how cosmological observables are
affected by inhomogeneities, while the other is focused on a theoretical
description of the inhomogeneous universe by means of a mean-field description.


title: (Multi)Matrix Models and Interacting Clones of Liouville Gravity

abstract:
  Large-N matrix models coupled via multitrace operators are used to define,
via appropriate double-scaling limits, solvable models of interacting
multi-string theories. It is shown that although such theories are non-local at
the world-sheet level they have a simple description of the spacetime physics.
Such theories share the main characteristics of similarly coupled
higher-dimensional CFTs. An interpretation has been given in the past of
similar continuum limits in terms of Liouville interactions that violate the
Seiberg bound. We provide a novel interpretation of this relation which agrees
with the current understanding of Liouville theory and analogous observations
in the AdS/CFT correspondence.


title: Exact Lattice Supersymmetry at Large N

abstract:
  Employing a novel type of non-commutative product in the Dirac-Kahler twisted
superspace on a lattice, we formulate a field theoretically rigid framework of
extended supersymmetry on a lattice. As a first example of this treatment, we
calculate one-loop (in some cases any loops) quantum corrections for a twisted
Wess-Zumino model with N \times N hermitian matrix superfields on a two
dimensional lattice. The calculations are entirely given in a lattice
superfield framework. We report that the mass and the coupling constant are
exactly protected from the radiative corrections at non-zero lattice spacing as
far as the planar diagrams are concerned, which implies the realization of
exact lattice supersymmetry w.r.t. all the supercharges in the large-N limit.


title:
Risk Assessment For Spreadsheet Developments: Choosing Which Models to
  Audit

abstract:
  Errors in spreadsheet applications and models are alarmingly common (some
authorities, with justification cite spreadsheets containing errors as the norm
rather than the exception). Faced with this body of evidence, the auditor can
be faced with a huge task - the temptation may be to launch code inspections
for every spreadsheet in an organisation. This can be very expensive and
time-consuming. This paper describes risk assessment based on the "SpACE" audit
methodology used by H M Customs & Excise's tax inspectors. This allows the
auditor to target resources on the spreadsheets posing the highest risk of
error, and justify the deployment of those resources to managers and clients.
Since the opposite of audit risk is audit assurance the paper also offers an
overview of some elements of good practice in the use of spreadsheets in
business.


title:
Relativistic transport theory for simple fluids at first order in the
  gradients: a stable picture

abstract:
  In this paper we show how using a relativistic kinetic equation the ensuing
expression for the heat flux can be casted in the form required by Classical
Irreversible Thermodynamics. Indeed, it is linearly related to the temperature
and number density gradients and not to the acceleration as the so called
\textit{first order in the gradients} theories propose. Since the specific
expressions for the transport coefficients are irrelevant for our purposes, the
BGK form of the kinetic equation is used. Moreover, from the resulting
hydrodynamic equations it is readily seen that the equilibrium state is stable
in the presence of the spontaneous fluctuations in the transverse hydrodynamic
velocity mode of the simple relativistic fluid. The implications of this result
are thoroughly discussed.


title:
Extracting Angular Diameter Distance and Expansion Rate of the Universe
  from Two-dimensional Galaxy Power Spectrum at High Redshifts: Baryon Acoustic
  Oscillation Fitting versus Full Modeling

abstract:
  We present a method for extracting the angular diameter distances, $D_A$, and
the expansion rates, $H$, of the universe from the {\it two-dimensional} Baryon
Acoustic Oscillations (BAO) in the galaxy power spectrum. Our method builds
upon the existing algorithm called the "fit-and-extract" (FITEX) method, which
allows one to extract only $D_A^2/H$ from a spherically averaged
one-dimensional power spectrum. We develop the FITEX-2d method, an extension of
the FITEX method, to include the two-dimensional information, which allows us
to extract $D_A$ and $H$ simultaneously. We test the FITEX-2d method using the
Millennium Simulation as well as simplified Monte Carlo simulations with a
bigger volume. The BAOs, however, contain only a limited amount of information.
We show that the full modeling, including the overall shape of the power
spectrum, yields much better determinations of $D_A$ and $H$, hence the dark
energy equation of state parameters such as $w_0$ and $w_a$, than the BAO-only
analysis by more than a factor of two, provided that non-linear effects are
under control.


title:
Extraordinary sensitivity of the electronic structure and properties of
  single-walled carbon nanotubes to molecular charge-transfer

abstract:
  Interaction of single-walled carbon nanotubes with electron donor and
acceptor molecules causes significant changes in the electronic and Raman
spectra, the relative proportion of the metallic species increasing on electron
donation through molecular charge transfer, as also verified by electrical
resistivity measurements.


title:
A common model for superluminal propagation in absorbing atomic media
  and lossy metastructures

abstract:
  We analyse the superluminal propagation of narrow-band pulses at resonances
in dissipative media. The output waveform is an attenuated, undistorted,
time-advanced version of the input which can be interpreted as the result of
the interference of two scaled replicas of the input having a positive relative
delay. The proposed analysis applies both to the propagation in a passive bulk
medium at an electronic resonance and in a dielectric waveguide coupled to a
lossy micro-ring resonator. This latter case provides a clear insight of the
underlying physical phenomena.


title: Casimir forces between cylinders and plates

abstract:
  We study collective interaction effects that result from the change of free
quantum electrodynamic field fluctuations by one- and two-dimensional perfect
metal structures. The Casimir interactions in geometries containing plates and
cylinders is explicitly computed using partial wave expansions of constrained
path integrals. We generalize previously obtained results and provide a more
detailed description of the technical aspects of the approach \cite{Emig06}. We
find that the interactions involving cylinders have a weak logarithmic
dependence on the cylinder radius, reflecting that one-dimensional
perturbations are marginally relevant in 4D space-time. For geometries
containing two cylinders and one or two plates, we confirm a previously found
non-monotonic dependence of the interaction on the object's separations which
does not follow from pair-wise summation of two-body forces. Qualitatively,
this effect is explained in terms of fluctuating charges and currents and their
mirror images.


title:
Changes in the electronic structure and properties of graphene induced
  by molecular charge-transfer

abstract:
  Interaction with electron donor and acceptor molecules such as aniline and
nitrobenzene brings about marked changes in the Raman spectrum and the
electronic structure of graphene, prepared by the exfoliation of graphitic
oxide.


title: Differential Conformal Superalgebras and their Forms

abstract:
  We introduce the formalism of differential conformal superalgebras, which we
show leads to the "correct" automorphism group functor and accompanying descent
theory in the conformal setting. As an application, we classify forms of N=2
and N=4 conformal superalgebras by means of Galois cohomology.


title:
Broadband electrically detected magnetic resonance of phosphorus donors
  in a silicon field-effect transistor

abstract:
  We report electrically detected magnetic resonance of phosphorus donors in a
silicon field-effect transistor. An on-chip transmission line is used to
generate the oscillating magnetic field allowing broadband operation. At
milli-kelvin temperatures, continuous wave spectra were obtained up to 40 GHz,
using both magnetic field and microwave frequency modulation. The spectra
reveal the hyperfine-split electron spin resonances characteristic for Si:P and
a central feature which displays the fingerprint of spin-spin scattering in the
two-dimensional electron gas.


title:
Isocurvature fluctuations in Affleck-Dine mechanism and constraints on
  inflation models

abstract:
  We reconsider the Affleck-Dine mechanism for baryogenesis and show that the
baryonic isocurvature fluctuations are generated in many inflation models in
supergravity. The inflationary scale and the reheating temperature must satisfy
certain constraints to avoid too large baryonic isocurvature fluctuations.


title: Buried treasure in the sand of the QCD vacuum

abstract:
  The short-range structure of the 2+1 flavour QCD vacuum is studied through
visualisations of the topological charge density. Of particular interest is a
new Gaussian weighted smearing algorithm which is applied to the rough
topological charge density to disclose underlying long range structure. The
results provide support for the view of the QCD vacuum as a sandwich of
sign-alternating sheets of charge, with a long-range structure hidden beneath.


title: Neural network learning of optimal Kalman prediction and control

abstract:
  Although there are many neural network (NN) algorithms for prediction and for
control, and although methods for optimal estimation (including filtering and
prediction) and for optimal control in linear systems were provided by Kalman
in 1960 (with nonlinear extensions since then), there has been, to my
knowledge, no NN algorithm that learns either Kalman prediction or Kalman
control (apart from the special case of stationary control). Here we show how
optimal Kalman prediction and control (KPC), as well as system identification,
can be learned and executed by a recurrent neural network composed of
linear-response nodes, using as input only a stream of noisy measurement data.
  The requirements of KPC appear to impose significant constraints on the
allowed NN circuitry and signal flows. The NN architecture implied by these
constraints bears certain resemblances to the local-circuit architecture of
mammalian cerebral cortex. We discuss these resemblances, as well as caveats
that limit our current ability to draw inferences for biological function. It
has been suggested that the local cortical circuit (LCC) architecture may
perform core functions (as yet unknown) that underlie sensory, motor,and other
cortical processing. It is reasonable to conjecture that such functions may
include prediction, the estimation or inference of missing or noisy sensory
data, and the goal-driven generation of control signals. The resemblances found
between the KPC NN architecture and that of the LCC are consistent with this
conjecture.


title: On the Capacity of Wireless Multicast Networks

abstract:
  The problem of maximizing the average rate in a multicast network subject to
a coverage constraint (minimum quality of service) is studied. Assuming the
channel state information is available only at the receiver side and single
antenna nodes, the highest expected rate achievable by a random user in the
network, called expected typical rate, is derived in two scenarios: hard
coverage constraint and soft coverage constraint. In the first case, the
coverage is expressed in terms of the outage probability, while in the second
case, the expected rate should satisfy certain minimum requirement. It is shown
that the optimum solution in both cases (achieving the highest expected typical
rate for given coverage requirements) is achieved by an infinite layer
superposition code for which the optimum power allocation among the different
layers is derived. For the MISO case, a suboptimal coding scheme is proposed,
which is shown to be asymptotically optimal, when the number of transmit
antennas grows at least logarithmically with the number of users in the
network.


title:
Coalition Games with Cooperative Transmission: A Cure for the Curse of
  Boundary Nodes in Selfish Packet-Forwarding Wireless Networks

abstract:
  In wireless packet-forwarding networks with selfish nodes, application of a
repeated game can induce the nodes to forward each others' packets, so that the
network performance can be improved. However, the nodes on the boundary of such
networks cannot benefit from this strategy, as the other nodes do not depend on
them. This problem is sometimes known as {\em the curse of the boundary nodes}.
To overcome this problem, an approach based on coalition games is proposed, in
which the boundary nodes can use cooperative transmission to help the backbone
nodes in the middle of the network. In return, the backbone nodes are willing
to forward the boundary nodes' packets. Here, the concept of core is used to
study the stability of the coalitions in such games. Then three types of
fairness are investigated, namely, min-max fairness using nucleolus, average
fairness using the Shapley function, and a newly proposed market fairness.
Based on the specific problem addressed in this paper, market fairness is a new
fairness concept involving fairness between multiple backbone nodes and
multiple boundary nodes. Finally, a protocol is designed using both repeated
games and coalition games. Simulation results show how boundary nodes and
backbone nodes form coalitions according to different fairness criteria. The
proposed protocol can improve the network connectivity by about 50%, compared
with pure repeated game schemes.


title: Covariant versions of Margolus-Levitin Theorem

abstract:
  The Margolus-Levitin Theorem is a limitation on the minimal evolving time of
a quantum system from its initial state to its orthogonal state. It also
supplies a bound on the maximal operations or events can occur within a volume
of spacetime. We compare Margolus-Levitin Theorem with other form of limitation
on minimal evolving time, and present covariant versions of Margolus-Levitin
Theorem in special and general relativity respectively. The relation among
entropy bound, maximum information flow and computational limit are discussed,
by applying the covariant versions of Margolus-Levitin Theorem.


title:
57Fe Mossbauer spectroscopy and magnetic measurements of oxygen
  deficient LaFeAsO

abstract:
  We report on the magnetic behavior of oxygen deficient LaFeAsO1-x (x-0.10)
compound, prepared by one-step synthesis, which crystallizes in the tetragonal
(S.G. P4/nmm) structure at room temperature. Resistivity measurements show a
strong anomaly near 150 K, which is ascribed to the spin density wave (SDW)
instability. On the other hand, dc magnetization data shows paramagnetic-like
features down to 5 K, with an effective moment of 0.83 mB/Fe. 57Fe Mossbauer
studies (MS) have been performed at 95 and 200 K. The spectra at both
temperatures are composed of two sub-spectra. At 200 K the major one (88%), is
almost a singlet, and corresponds to those Fe nuclei, which have two oxygen
ions in their close vicinity. The minor one, with a large quadrupole splitting,
corresponds to Fe nuclei, which have vacancies in their immediate neighborhood.
The spectrum at 95 K, exhibits a broadened magnetic split major (84%)
sub-spectrum and a very small magnetic splitting in the minor subspectrum. The
relative intensities of the subspectra facilitate in estimating the actual
amount of oxygen vacancies in the compound to be 7.0(5)%, instead of the
nominal LaFeAsO0.90. These results, when compared with reported 57Fe MS of
non-superconducting LaFeAsO and superconducting LaFeAsO0.9F0.1, confirm that
the studied LaFeAsO0.93 is a superconductivity-magnetism crossover compound of
the newly discovered Fe based superconducting family.


title:
Nonclassicality of single quantum excitation of a thermal field in
  thermal environments

abstract:
  The nonclassicality of single photon-added thermal states in the thermal
channel is investigated by exploring the volume of the negative part of the
Wigner function. The Wigner functions become positive when the decay time
exceeds a threshold value $\gamma{t}_c$, which only depends on the effective
temperature or mean thermal photon number of the thermal channel, but not
depends on the effective temperature of the initial thermal state. This
phenomenon is similar with the case of single quantum excitation of classical
coherent states in thermal channel. Furthermore, we firstly demonstrate
$\gamma{t}_c$ is the same for arbitrary pure or mixed nonclassical optical
fields with zero population in vacuum state.
  PACS numbers: 42.50.Dv, 03.65.Yz, 05.40.Ca


title:
Surface Homeomorphisms That Do Not Extend to Any Handlebody and the
  Johnson Filtration

abstract:
  We prove the existence of homeomorphisms of a closed, orientable surface of
genus 3 or greater that do not extend to any handlebody bounded by the surface.
We show that such homeomorphisms exist arbitrarily deep in the Johnson
filtration of the mapping class group. The second and third terms of the
Johnson filtration are the well-known Torelli group and Johnson subgroup,
respectively. Richard Hain has obtained very similar results by different
methods.


title: Remote atom entanglement in a fiber-connected three-atom system

abstract:
  An Ising-type atom-atom interaction is obtained in a fiber-connected
three-atom system. The interaction is effective when $\Delta\approx \gamma
_{0}\gg g$. The preparations of remote two-atom and three-atom entanglement
governed by this interaction are discussed in specific parameters region. The
overall two-atom entanglement is very small because of the existence of the
third atom. However, the three-atom entanglement can reach a maximum very close
to 1.


title:
Plasmons in the presence of Tamm-Shockley states with Rashba splitting
  at noble metal surfaces

abstract:
  Au(111) or similar noble metal surfaces feature Tamm-Shockley surface states
that are known to possess considerable spin-orbit splitting of the Rashba type
of order $\Delta=0.1$ eV. When interacting with an electromagnetic field such
states are expected to have resonances when the frequency of the field is near
the energy of the spin-orbit splitting $\Delta$. These resonances originate in
the intersubband transitions between spin-split subbands. Such resonances can
be observed in the frequency dependence of the surface impedance. Plasmons in
thin metal films are gapless and can be strongly affected by these spin
resonances, acquiring significant modification of the spectrum when it
intersects the $\omega=\Delta$ line. Finally, an interesting demonstration of
the intersubband resonances can be obtained when metal films are coated with
ionic dielectrics that have a frequency of longitudinal/transverse optical
phonons above/below $\Delta$. The dielectric function between the two optical
phonon frequencies is negative which forbids propagation of conventional
plasmon-polaritons. However, the presence of spin-orbit-split surface states
allows plasmon-polaritons to exist in this otherwise forbidden range of
frequencies.


title: Monotone Linear Relations: Maximality and Fitzpatrick Functions

abstract:
  We analyze and characterize maximal monotonicity of linear relations
(set-valued operators with linear graphs). An important tool in our study are
Fitzpatrick functions. The results obtained partially extend work on linear and
at most single-valued operators by Phelps and Simons and by Bauschke, Borwein
and Wang. Furthermore, a description of skew linear relations in terms of the
Fitzpatrick family is obtained. We also answer one of Simons problems by
showing that if a maximal monotone operator has a convex graph, then this graph
must actually be affine.


title:
Characterization of jacobian Newton polygons of plane branches and new
  criteria of irreducibility

abstract:
  In this paper we characterize, in two different ways, the Newton polygons
which are jacobian Newton polygons of a branch. These characterizations give in
particular combinatorial criteria of irreducibility for complex series in two
variables and necessary conditions which a complex curve has to satisfy in
order to be the discriminant of a complex plane branch.


title: Line Shifts, Broad-Line Region Inflow, and the Feeding of AGNs

abstract:
  Velocity-resolved reverberation mapping suggests that the broad-line regions
(BLRs) of AGNs can have significant net inflow. We use the STOKES radiative
transfer code to show that electron and Rayleigh scattering off the BLR and
torus naturally explains the blueshifted profiles of high-ionization lines and
the ionization dependence of the blueshifts. This result is insensitive to the
geometry of the scattering region. If correct, this model resolves the
long-standing conflict between the absence of outflow implied by
velocity-resolved reverberation mapping and the need for outflow if the
blueshifting is the result of obscuration. The accretion rate implied by the
inflow is sufficient to power the AGN. We suggest that the BLR is part of the
outer accretion disk and that similar MHD processes are operating. In the
scattering model the blueshifting is proportional to the accretion rate so
high-accretion-rate AGNs will show greater high-ionization line blueshifts as
is observed. Scattering can lead to systematically too high black hole mass
estimates from the C IV line. We note many similarities between narrow-line
region (NLR) and BLR blueshiftings, and suggest that NLR blueshiftings have a
similar explanation. Our model explains the higher blueshifts of broad
absorption line QSOs if they are more highly inclined. Rayleigh scattering from
the BLR and torus could be more important in the UV than electron scattering
for predominantly neutral material around AGNs. The importance of Rayleigh
scattering versus electron scattering can be assessed by comparing line
profiles at different wavelengths arising from the same emission-line region.


title: Approximate spacetime symmetries and conservation laws

abstract:
  A notion of geometric symmetry is introduced that generalizes the classical
concepts of Killing fields and other affine collineations. There is a sense in
which flows under these new vector fields minimize deformations of the
connection near a specified observer. Any exact affine collineations that may
exist are special cases. The remaining vector fields can all be interpreted as
analogs of Poincare and other well-known symmetries near timelike worldlines.
Approximate conservation laws generated by these objects are discussed for both
geodesics and extended matter distributions. One example is a generalized Komar
integral that may be taken to define the linear and angular momenta of a
spacetime volume as seen by a particular observer. This is evaluated explicitly
for a gravitational plane wave spacetime.


title:
Superoperator nonequilibrium Green's function theory of many-body
  systems; Applications to charge transfer and transport in open junctions

abstract:
  Nonequilibrium Green's functions provide a powerful tool for computing the
dynamical response and particle exchange statistics of coupled quantum systems.
We formulate the theory in terms of the density matrix in Liouville space and
introduce superoperator algebra that greatly simplifies the derivation and the
physical interpretation of all quantities. Expressions for various observables
are derived directly in real time in terms of superoperator nonequilibrium
Green's functions (SNGF), rather than the artificial time-loop required in
Schwinger's Hilbert-space formulation. Applications for computing interaction
energies, charge densities, average currents, current induced fluorescence,
electroluminescence and current fluctuation (electron counting) statistics are
discussed.


title:
Mott Phase in Polarized Two-component Atomic Fermi Lattice Gas:A
  Playground for S=1/2 Heisenberg Model in Magnetic Field

abstract:
  We investigate effects of pseudo-spin population imbalance on Mott phases in
1D trapped two-component atomic Fermi gases loaded on optical lattices based on
the repulsive Hubbard model in harmonic traps. By using the density matrix
renormalization group method, we numerically calculate density profiles of each
component and clarify the pseudo-spin magnetism. Consequently, we find that all
the features from weakly imbalance to fully polarized cases are well described
by S=1/2 antiferromagnetic Heisenberg chain under magnetic field. These results
indicate that the Mott phases offer experimental stages for studying various
interacting spin systems.


title: Multiferroic properties of Bi0.9- xLa0.1ErxFeO3 ceramics

abstract:
  Structural, electrical and magnetic properties of Bi0.9-xLa0.1ErxFeO3
(BLEFOx) (x = 0.05, 0.07, 0.1) polycrystalline ceramics prepared by solid
solution route were studied. A phase transition from rhombohedral phase to
monoclinic phase was observed for x=0.05-0.1 in (BLEFOx). We have measured
phase transition temperatures both alpha-beta transition and low-Temperature
(low-T) transitions in doped BiFeO3. The transition peak near to 835C
corresponds to alpha to beta-phase transition of BiFeO3 were measured using
diffential thermal analysis (DTA). Dielectric measurements shows the low-T
transitions in BLEFOx (x = 0.05-0.1). Relatively high remanent magnetization of
0.1178emu/gm at 8T was observed in BLEFOx (x = 0.1).


title:
Possibility of Detecting Moons of Pulsar Planets Through Time-of-Arrival
  Analysis

abstract:
  The perturbation caused by planet-moon binarity on the time-of-arrival signal
of a pulsar with an orbiting planet is derived for the case in which the orbits
of the moon and the planet-moon barycenter are both circular and coplanar. The
signal consists of two sinusoids with frequency (2n_p - 3n_b) and (2n_p - n_b
), where n_p and n_b are the mean motions of the planet and moon around their
barycenter, and the planet-moon system around the host, respectively. The
amplitude of the signal is equal to the fraction sin I[9(M_p M_m)/16(M_p +
M_m)^2] [r/R]^5 of the system crossing time R/c, where M_p and M_m are the the
masses of the planet and moon, r is their orbital separation, R is the distance
between the host pulsar and planet-moon barycenter, I is the inclination of the
orbital plane of the planet, and c is the speed of light. The analysis is
applied to the case of PSR B1620-26 b, a pulsar planet, to constrain the
orbital separation and mass of any possible moons. We find that a stable moon
orbiting this pulsar planet could be detected, if the moon had a separation of
about one fiftieth of that of the orbit of the planet around the pulsar, and a
mass ratio to the planet of ~5% or larger.


title: Anatomy of luminosity functions: the 2dFGRS example

abstract:
  Aims. We use the 2dF Galaxy Redshift Survey to derive the luminosity function
(LF) of the first-ranked (brightest) group/cluster galaxies, the LF of
second-ranked, satellite and isolated galaxies, and the LF of groups of
galaxies.
  Methods. We investigate the LFs of different samples in various environments:
in voids, filaments, superclusters and supercluster cores. We compare the
derived LFs with the Schechter and double-power-law analytical expressions. We
also analyze the luminosities of isolated galaxies.
  Results. We find strong environmental dependency of luminosity functions of
all populations. The luminosities of first-ranked galaxies have a lower limit,
depending on the global environment (higher in supercluster cores, and absent
in voids). The LF of second-ranked galaxies in high-density regions is similar
to the LF of first-ranked galaxies in a lower-density environment. The
brightest isolated galaxies can be identified with first-ranked galaxies at
distances where the remaining galaxies lie outside the observational window
used in the survey.
  Conclusions. The galaxy and cluster LFs can be well approximated by a
double-power-law; the widely used Schechter function does not describe well the
bright end and the bend of the LFs. Properties of the LFs reflect differences
in the evolution of galaxies and their groups in different environments.


title: Primordial statistical anisotropy generated at the end of inflation

abstract:
  We present a new mechanism for generating primordial statistical anisotropy
of curvature perturbations. We introduce a vector field which has a non-minimal
kinetic term and couples with a waterfall field in hybrid inflation model. In
such a system, the vector field gives fluctuations of the end of inflation and
hence induces a subcomponent of curvature perturbations. Since the vector has a
preferred direction, the statistical anisotropy could appear in the
fluctuations. We present the explicit formula for the statistical anisotropy in
the primordial power spectrum and the bispectrum of curvature perturbations.
Interestingly, there is the possibility that the statistical anisotropy does
not appear in the power spectrum but does appear in the bispectrum. We also
find that the statistical anisotropy provides the shape dependence to the
bispectrum.


title:
Spectro-Polarimetric Observation of an Emerging Flux Region: Triggering
  Mechanism of Ellerman Bombs

abstract:
  High spatial resolution observation of an emerging flux region (EFR) was done
using a vector magnetograph and a H-alpha Lyot filtergraph with Domeless Solar
Telescope at Hida Observatory on October 22, 2006. In H-alpha wing images, we
could see many Ellerman bombs (EBs) in the EFR. Two observation modes, slit
scan and slit fixed, were performed with the vector magnetograph, along with
H-alpha filtergraph. Using H-alpha wing images, we detected 12 EBs during slit
scan observation period and 9 EBs during slit fixed observation period. With
slit scan observation, we found that all the EBs were distributed in the area
where the spatial gradient of vertical field intensity was large, which
indicates the possibility of rapid topological change in magnetic field in the
area of EBs. With slit fixed observation, we found that EBs were distributed in
the areas of undulatory magnetic fields, both in vertical and horizontal
components. This paper is the first to report the undulatory pattern in
horizontal components of magnetic field, which is also evidence for emerging
magnetic flux by Parker instability. These results allow us to confirm the
association between EBs and emerging flux tubes. Three triggering mechanism of
EBs is discussed with respect to emerging flux tubes: 9 out of 21 EBs occurred
at the footpoints of emerging flux tubes, 8 out of 21 EBs occurred at the top
of emerging flux tubes, and 4 out of 21 EBs occurred at unipolar region. Each
case can be explained by magnetic reconnection in the low chromosphere.


title:
Study of Nuclear Suppression at Large Forward Rapidities in d-Au
  Collisions at Relativistic and Ultrarelativistic Energies

abstract:
  We study a strong suppression of the relative production rate (d-Au)/(p-p)
for inclusive high-pT hadrons of different species at large forward rapidities
(large Feynman xF). The model predictions calculated in the light-cone dipole
approach are in a good agreement with the recent measurements by the BRAHMS and
STAR Collaborations at the BNL Relativistic Heavy Ion Collider. We predict a
similar suppression at large pT and large xF also at lower energies, where no
effect of coherence is possible. It allows to exclude the saturation models or
the models based on Color Glass Condensate from interpretation of nuclear
effects.


title:
Primordial matter density contrast and the size of the very early
  universe in the Quantum Big Bang theory of the cosmological constant

abstract:
  We calculate the amount of primordial matter density contrast and the size of
the very early universe in the recent Quantum Big Bang theory [arXiv:0705.4549
[gr-qc](2007)] of the cosmological constant. We obtain $(\delta\rho/\rho)_M =
1.75 \times 10^{-5}$, {\it without} the introduction of an adjustable free
parameter. Harrison-Zel'dovich $k$-dependence with $A = 64/9\pi^2 = 0.72$ and
$n = 1$ in $|\delta_k|^2 = Ak^n$ arises inherently. The size of the universe
with which it enters the classical Friedmann-Robertson-Walker (FRW) phase comes
out to be 0.2 cm. We conclude that the hypothesis of classical inflation at an
early stage of cosmic evolution is {\bf not} needed.


title:
Automorphisms of Coxeter groups and Lusztig's conjectures for Hecke
  algebras with unequal parameters

abstract:
  Let $(W,S)$ be a Coxeter system, let $G$ be a finite solvable group of
automorphisms of $(W,S)$ and let $\varphi$ be a weight function which is
invariant under $G$. Let $\varphi_G$ denote the weight function on $W^G$
obtained by restriction from $\varphi$. The aim of this paper is to compare the
${\mathbf{a}}$-function, the set of Duflo involutions and the Kazhdan-Lusztig
cells associated to $(W,\varphi)$ and to $(W^G,\varphi_G)$, provided that
Lusztig's Conjectures hold.


title: Particle creation in a time-dependent electric field revisited

abstract:
  We adopt the general formalism for analyzing evolution of gaussian states of
quantized fields in time-dependent backgrounds in the Schrodinger picture
(presented in detail in arXiv:0708.1233 and 0708.1237) to study the example of
a spatially uniform electric field background (in a time-dependent gauge) which
is kept turned on for a finite duration of time. In particular, we study the
\emph{time-dependent} particle content, defined in terms of the concept of
instantaneous eigenstates, and describe how it captures the time evolution of
the quantized field modes. The actual particle creation process occurs over a
relatively short interval in time, and the particle content saturates rather
quickly. We also compare the \emph{power spectrum} of the field modes, computed
in the asymptotic limit, with the corresponding situation in a cosmological de
Sitter background. Particle creation under the influence of a spiked electric
field localized in time, as a particular limiting case of the above general
model, is also considered.


title: Gross features of finite nuclei at finite temperatures

abstract:
  A simple expression is obtained for the low temperature behavior of the
energy and entropy of finite nuclei for $20\leq A\leq 250$. The dependence on
$A$ of these quantities is for the most part due to the presence of the
asymmetry energy.


title:
From itinerant to local-moment antiferromagnetism in Kondo lattices:
  Adiabatic continuity vs. quantum phase transitions

abstract:
  Motivated by both experimental and theoretical activities, we discuss the
fate of Kondo screening and possible quantum phase transitions in
antiferromagnetically ordered phases of Kondo lattices. While transitions with
topological changes of the Fermi surface may occur, we demonstrate that an
entirely continuous evolution from itinerant to local-moment antiferromagnetism
(i.e. from strong to negligible Kondo screening) is possible as well. This
situation is in contrast to that in a non-symmetry-broken situation where a
quantum phase transition towards an exotic metallic spin-liquid state
necessarily accompanies the disappearance of Kondo screening. We discuss
criteria for the existence of topological transitions in the antiferromagnetic
phase, as well as implications for theoretical scenarios and for current
experiments.


title: On pluricanonical systems of algebraic varieties of general type

abstract:
  We extend Kollar's technique to look for an explicit function h(n) with phi_m
birational onto its image for all integers $m\geq h(n)$ and for all
n-dimensional nonsingular projective varieties of general type.


title: Baxter's Q-operators for supersymmetric spin chains

abstract:
  We develop Yang-Baxter integrability structures connected with the quantum
affine superalgebra Uq(\hat sl(2|1)). Baxter's Q-operators are explicitly
constructed as supertraces of certain monodromy matrices associated with
(q-deformed) bosonic and fermionic oscillator algebras. There are six different
Q-operators in this case, obeying a few fundamental fusion relations, which
imply all functional relations between various commuting transfer matrices. The
results are universal in the sense that they do not depend on the quantum space
of states and apply both to lattice models and to continuous quantum field
theory models as well.

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


title:
Unified explanation of the Kadowaki-Woods ratio in strongly correlated
  materials

abstract:
  Discoveries of ratios whose values are constant within broad classes of
materials have led to many deep physical insights. The Kadowaki-Woods ratio
(KWR) compares the temperature dependence of a metal's resistivity to that of
its heat capacity; thereby probing the relationship between the
electron-electron scattering rate and the renormalisation of the electron mass.
However, the KWR takes very different values in different materials. Here we
introduce a ratio, closely related to the KWR, that includes the effects of
carrier density and spatial dimensionality and takes the same (predicted) value
in organic charge transfer salts, transition metal oxides, heavy fermions and
transition metals - despite the numerator and denominator varying by ten orders
of magnitude. Hence, in these materials, the same emergent physics is
responsible for the mass enhancement and the quadratic temperature dependence
of the resistivity and no exotic explanations of their KWRs are required.


title:
Kink structure in the electronic dispersion of high-Tc superconductors
  from the electron-phonon interaction

abstract:
  We investigate the electronic dispersion of high-Tc superconductor on the
basis of the two-dimensional three-band Hubbard model with the electron-phonon
interaction together with the strong electron-electron interaction. In our
model, it is shown across the hole-doped region of high-Tc superconductor that
the electron-phonon interaction makes a dispersion kink, observed along the
nodal direction, and that the small isotope effect appears on the electronic
dispersion.


title: Spin chain model for correlated quantum channels

abstract:
  We analyze the quality of the quantum information transmission along a
correlated quantum channel by studying the average fidelity between input and
output states and the average output purity, giving bounds for the entropy of
the channel. Noise correlations in the channel are modeled by the coupling of
each channel use with an element of a one dimensional interacting quantum spin
chain. Criticality of the environment chain is seen to emerge in the changes of
the fidelity and of the purity.


title:
Quasi-Simultaneous Two Band Optical Micro-Variability of Luminous
  Radio-Quiet QSOs

abstract:
  We report the first results of quasi-simultaneous two passband optical
monitoring of six quasi-stellar objects to search for micro-variability. We
carried out photometric monitoring of these sources in an alternating sequence
of R and V passbands, for five radio-quiet quasi-stellar objects (RQQSOs),
0748+291, 0824+098, 0832+251, 1101+319, 1225+317 and one radio-loud
quasi-stellar object (RLQSO), 1410+429. No micro-variability was detected in
any of the RQQSOs, but convincing micro-variability was detected in the RLQSO
on two successive nights it was observed. Using the compiled data of optical
micro-variability of RQQSOs till date, we got the duty cycle for
micro-variability in RQQSOs is $\sim$ 10%. The present investigation indicates
that micro-variability is not a persistent property of RQQSOs but an occasional
incident.


title: Flat Universe with Hyperbolic Voids

abstract:
  The properties of geodesics flow are studied in a Friedmann-Robertson-Walker
metric perturbed due to the inhomogeneities of matter. The basic, averaged
Jacobi equation is derived, which reveals that the low density regions (voids)
are able to induce hyperbolicity, even if the global curvature of the Universe
is zero or slightly positive. It is shown that the energy independence is a
characteristic property of these geometric effects. The importance of these
conclusions is determined by the temperature independent ellipticity of
excursion sets and regions of different randomness found in Kolmogorov CMB
maps.


title: Adjoint bi-continuous semigroups and semigroups on the space of measures

abstract:
  For a given bi-continuous semigroup T on a Banach space X we define its
adjoint on an appropriate closed subspace X^o of the norm dual X'. Under some
abstract conditions this adjoint semigroup is again bi-continuous with respect
to the weak topology (X^o,X). An application is the following: For K a Polish
space we consider operator semigroups on the space C(K) of bounded, continuous
functions (endowed with the compact-open topology) and on the space M(K) of
bounded Baire measures (endowed with the weak*-topology). We show that
bi-continuous semigroups on M(K) are precisely those that are adjoints of a
bi-continuous semigroups on C(K). We also prove that the class of bi-continuous
semigroups on C(K) with respect to the compact-open topology coincides with the
class of equicontinuous semigroups with respect to the strict topology. In
general, if K is not Polish space this is not the case.


title: Coupled system description of perturbed KdV equation

abstract:
  In the multiple-soliton case, the freedom in the expansion of the solution of
the perturbed KdV equation is exploited so as to transform the equation into a
system of two equations: The (inte-grable) Normal Form for KdV-type solitons,
which obey the usual infinity of KdV-conservation laws, and an auxiliary
equation that describes the contribution of obstacles to asymptotic
inte-grability, which arise from the second order onwards. The analysis has
been carried through the third order in the expansion. Within that order, the
solution of the auxiliary equation is a con-served quantity.


title: On Shintani's ray class invariant for totally real number fields

abstract:
  We introduce a ray class invariant $X(C)$ for a totally real field, following
Shintani's work in the real quadratic case. We prove a factorization formula
$X=X_1... X_n$ where each $X_i=X_i(C)$ corresponds to a real place. Although
this factorization depends a priori on some choices (especially on a cone
decomposition), we can show that it is actually independent of these choices.
Finally, we describe the behavior of $X_i(C)$ when the signature of $C$ at a
real place is changed. This last result is also interpreted into an interesting
behavior of the derivative $L'(0,\chi)$ of $L$-functions.


title:
Theoretical model of viscous friction inside steadily sheared foams and
  concentrated emulsions

abstract:
  In a recent letter (Denkov et al., Phys. Rev. Lett., vol. 100 (2008) p.
138301) we calculated theoretically the macroscopic viscous stress of steadily
sheared foam/emulsion from the energy dissipated inside the transient planar
films, formed between neighboring bubbles/drops in the shear flow. The model
predicts that the viscous stress in these systems should be a proportional to
Ca^1/2, where Ca is the capillary number and n = 1/2 is the power-law index. In
the current paper we explain in detail our model and develop it further in
several aspects: First, we extend the model to account for the effects of
viscous friction in the curved meniscus regions, surrounding the planar films,
on the dynamics of film formation and on the total viscous stress. Second, we
consider the effects of surface forces (electrostatic, van der Waals, etc.)
acting between the surfaces of the neighboring bubbles/drops and show that
these forces could be important in emulsions, due to the relatively small
thickness of emulsion films (often comparable to the range of action of the
surface forces). Third, additional consideration is made for bubbles/drops
exhibiting high surface viscosity, for which we demonstrate an additional
contribution to the macroscopic viscous stress, created by the surface
dissipation of energy. The new upgraded model predicts that the energy
dissipation at the bubble/drop surface leads to power-law index n < 1/2,
whereas the contribution of the surface forces leads to n > 1/2, which explains
the rich variety of foam/emulsion behaviors observed upon steady shear. Various
comparisons are made between model predictions and experimental results for
both foams and emulsions, and a very good agreement is found.


title:
Electric field-induced spin textures in a superlattice with Rashba and
  Dresselhaus spin-orbit coupling

abstract:
  The DC charge current, field-induced spin polarization and spin textures are
studied in the 1D gated superlattice with both fixed and varying Rashba and
Dresselhaus contributions to spin-orbit coupling. It is found that a spin
component with zero mean value can demonstrate non-vanishing field-induced spin
texture in a superlattice cell which can be probed experimentally, with the
highest amplitudes achievable in an interval of comparable Rashba and
Dresselhaus terms. The consideration of the finite parameters for collision
rate and temperature is found to be non-destructive for the calculated current
and spin characteristics depending on all states below the Fermi level.


title: Robustness of planar random graphs to targeted attacks

abstract:
  In this paper, robustness of planar trivalent random graphs to targeted
attacks of highest connected nodes is investigated using numerical simulations.
It is shown that these graphs are relatively robust. The nonrandom node removal
process of targeted attacks is also investigated as a special case of
non-uniform site percolation. Critical exponents are calculated by measuring
various properties of the distribution of percolation clusters. They are found
to be roughly compatible with critical exponents of uniform percolation on
these graphs.


title:
Self-regulation of the reconnecting current layer in relativistic pair
  plasma reconnection

abstract:
  We investigate properties of the reconnecting current layer in relativistic
pair plasma reconnection. We found that the current layer self-regulates its
thickness when the current layer runs out current carriers, and so relativistic
reconnection retains a fast reconnection rate. Constructing a steady state
Sweet-Parker model, we discuss conditions for the current sheet expansion.
Based on the energy argument, we conclude that the incompressible assumption is
invalid in relativistic Sweet-Parker reconnection. The guide field cases are
more incompressible than the anti-parallel cases, and we find a more
significant current sheet expansion.


title:
Constraints on the Evolution of Black Hole Spin due to
  Magnetohydrodynamic Accretion

abstract:
  Stationary and axisymmetric ideal magnetohydrodynamic (MHD) accretion onto a
black hole is studied analytically. The accreting plasma ejected from a plasma
source with low velocity must be super-fast magnetosonic before passing through
the event horizon. We work out and apply a trans-fast magnetosonic solution
without the detailed analysis of the regularity conditions at the magnetosonic
point, by introducing the bending angle $\beta$ of magnetic field line, which
is the ratio of the toroidal and poloidal components of the magnetic field. To
accrete onto a black hole, the trans-magnetosonic solution has some
restrictions on $\beta$, which are related to the field-aligned parameters of
the MHD flows. One of the restrictions gives the boundary condition at the
event horizon for the inclination of a magnetic field line. We find that this
inclination is related to the energy and angular momentum transport to the
black hole. Then, we discuss the spin-up/down process of a rotating black hole
by cold MHD inflows in a secular evolution timescale. There are two asymptotic
states for the spin evolution. One is that the angular velocity of the black
hole approaches to that of the magnetic field line, and the other is that the
spin-up effect by the positive angular momentum influx and the spin-down effect
by the energy influx (as the mass-energy influx) are canceled. We also show
that the MHD inflows prevents the evolution to the maximally rotating black
hole.


title:
Bulk and surface structure of the clean and adsorbate-covered decagonal
  Al-Co-Ni quasicrystal

abstract:
  We review our Al adsorption experiments on the tenfold-symmetry surface of
the decagonal Al-Co-Ni quasicrystal and present computational simulations of
adsorption on a structural model based on a fundamental Al-Co cluster with 20
\AA diameter, symmetry $\bar{10}2m$, and 8 \AA periodicity. This cluster is the
building unit of $\tau ^2$-Al$_{13}$Co$_4$, from which, by a sequence of minor
changes, the structures of the phases in the stability region of decagonal
Al-Co-Ni can be derived. The model used for the decagonal
Al$_{70}$Co$_{15}$Ni$_{15}$ is an idealized model with a two-layer periodicity
(4 \AA) and no chemical or structural disorder. We find that the bulk and
surface properties of this model are in good agreement with experiments. Our
molecular-dynamics simulations of Al adsorption reproduce the experimental
results and show that by varying the thermal relaxation rates of the adsorbed
layer, a variety of different surface morphologies can be achieved. We also
present our recent experiments on dissociative adsorption of oxygen on the
decagonal surface.


title: V405 Aurigae: A High Magnetic Field Intermediate Polar

abstract:
  Our simultaneous multicolor (UBVRI) circular polarimetry has revealed nearly
sinusoidal variation over the WD spin cycle, and almost symmetric positive and
negative polarization excursions. Maximum amplitudes are observed in the B and
V bands (+-3 %). This is the first time that polarization peaking in the blue
has been discovered in an IP, and suggests that V405 Aur is the highest
magnetic field IP found so far. The polarized flux spectrum is similar to those
found in polars with magnetic fields in the range B ~ 25-50 MG. Our low
resolution circular spectropolarimetry has given evidence of transient features
which can be fitted by cyclotron harmonics n = 6, 7, and 8, at a field of B =
31.5 +- 0.8 MG, consistent with the broad-band polarized flux spectrum. Timings
of the circular polarization zero crossovers put strict upper limits on WD spin
period changes and indicate that the WD in V405 Aur is currently accreting
closely at the spin equilibrium rate, with very long synchronization
timescales, T_s > 10^9 yr. For the observed spin to orbital period ratio,
P_{spin}/P_{orb} = 0.0365, and P_{orb} ~ 4.15 hr, existing numerical accretion
models predict spin equilibrium condition with B ~ 30 MG if the mass ratio of
the binary components is q_1 ~ 0.4. The high magnetic field makes V405 Aur a
likely candidate as a progenitor of a polar.


title: From Data Topology to a Modular Classifier

abstract:
  This article describes an approach to designing a distributed and modular
neural classifier. This approach introduces a new hierarchical clustering that
enables one to determine reliable regions in the representation space by
exploiting supervised information. A multilayer perceptron is then associated
with each of these detected clusters and charged with recognizing elements of
the associated cluster while rejecting all others. The obtained global
classifier is comprised of a set of cooperating neural networks and completed
by a K-nearest neighbor classifier charged with treating elements rejected by
all the neural networks. Experimental results for the handwritten digit
recognition problem and comparison with neural and statistical nonmodular
classifiers are given.


title:
On the contribution of nearly-critical spin and charge collective modes
  to the Raman spectra of high-Tc cuprates

abstract:
  We discuss how Raman spectra are affected by nearly-critical spin and charge
collective modes, which are coupled to charge carriers near a stripe quantum
critical point. We show that specific fingerprints of nearly-critical
collective modes can indeed be observed in Raman spectra and that the
selectivity of Raman spectroscopy in momentum space may also be exploited to
distinguish the spin and charge contribution. We apply our results to discuss
the spectra of high-Tc superconducting cuprates finding that the collective
modes should have masses with substantial temperature dependence in agreement
with their nearly critical character. Moreover spin modes should be more
diffusive than charge modes indicating that in stripes the charge is nearly
ordered, while spin modes are strongly overdamped and fluctuate with high
frequency.


title:
Interference bands in decays of doubly-charged Higgs bosons to dileptons
  in the minimal type-II seesaw model at the TeV scale

abstract:
  The dileptonic decays of doubly-charged Higgs bosons H^{\pm\pm} are
investigated in the minimal type-II seesaw model with one Higgs triplet \Delta
and one heavy Majorana neutrino N_1 at the TeV scale. We show that the
branching ratios {\cal B}(H^{\pm\pm} \to l^\pm_\alpha l^\pm_\beta) depend not
only on the mass and mixing parameters of three light neutrinos \nu_i (for
i=1,2,3), but also on those of N_1. Assuming the mass of N_1 to lie in the
range 200 GeV--1 TeV, we figure out the generous interference bands for the
contributions of \nu_i and N_1 to {\cal B}(H^{\pm\pm} \to l^\pm_\alpha
l^\pm_\beta): \sqrt{|\sin\theta_{i4} \sin\theta_{j4}|} \sim 10^{-8}--10^{-5},
where \theta_{i4} and \theta_{j4} measure the strength of charged-current
interactions of N_1. We illustrate some salient features of the interference
bands by considering three typical mass patterns of \nu_i, and stress that it
is very difficult to distinguish the type-II seesaw model from the triplet
seesaw model in such a parameter region at the Large Hadron Collider.


title: Nernst effect of epitaxial YBCO films doped with Ca and Zn

abstract:
  We report Nernst effect measurements for some crystalline films of Ca and
Zn-doped yttrium barium copper oxide grown by pulsed laser deposition. We argue
that our results and most of the published data for LSCO are consistent with
the theory of Gaussian superconducting fluctuations.


title: Nonlinear Quantum Cosmology

abstract:
  We study the effects of an information-theoretically motivated nonlinear
correction to the Wheeler-deWitt equation in the minisuperspace scheme for
flat, $k=0$, Friedmann-Robertson-Walker (FRW) universes. When the only matter
is a cosmological constant, the nonlinearity can provide a barrier that screens
the original Big Bang, leading to the quantum creation of a universe through
tunneling just as in the $k=1$ case. When the matter is instead a free massless
scalar field, the nonlinearity can again prevent a contracting classical
universe from reaching zero size by creating a bounce. Our studies here are
self-consistent to leading order in perturbation theory for the nonlinear
effects.


title:
Probing Fermionic Condensates by Fast-Sweep Projection onto Feshbach
  Molecules

abstract:
  Fast sweep projection onto Feshbach molecules has been widely used as a probe
of fermionic condensates. By determining the exact dynamics of a pair of atoms
in time varying magnetic fields, we calculate the number of condensed and
noncondensed molecules created after fast magnetic field sweeps from the BCS to
the BEC side of the resonances in $^{40}$K and $^{6}$Li, for different sweep
rates and a range of initial and final fields. We discuss the relation between
the initial fermionic condensate fraction and the molecular condensate fraction
measured after the sweep.


title:
Stokes imaging polarimetry using image restoration at the Swedish 1-m
  Solar Telescope

abstract:
  Aims: We aim to achieve high spatial resolution as well as high polarimetric
sensitivity, using an earth-based 1m-class solar telescope, for the study of
magnetic fine structure on the Sun. Methods: We use a setup with 3 high-speed,
low-noise cameras to construct datasets with interleaved polarimetric states,
particularly suitable for Multi-Object Multi-Frame Blind Deconvolution image
restorations. We discuss the polarimetric calibration routine as well as
various potential sources of error in the results. Results: We obtained near
diffraction limited images, with a noise level of approximately 10^(-3)
I(cont). We confirm that dark-cores have a weaker magnetic field and at a lower
inclination angle with respect to the solar surface than the edges of the
penumbral filament. We show that the magnetic field strength in
faculae-striations is significantly lower than in other nearby parts of the
faculae.


title: Tentative detection of phosphine in IRC+10216

abstract:
  The J,K = 1,0-0,0 rotational transition of phosphine (PH3) at 267 GHz has
been tentatively identified with a T_MB = 40 mK spectral line observed with the
IRAM 30-m telescope in the C-star envelope IRC+10216. A radiative transfer
model has been used to fit the observed line profile. The derived PH3 abundance
relative to H2 is 6 x 10^(-9), although it may have a large uncertainty due to
the lack of knowledge about the spatial distribution of this species. If our
identification is correct, it implies that PH3 has a similar abundance to that
reported for HCP in this source, and that these two molecules (HCP and PH3)
together take up about 5 % of phosphorus in IRC+10216. The abundance of PH3, as
that of other hydrides in this source, is not well explained by conventional
gas phase LTE and non-LTE chemical models, and may imply formation on grain
surfaces.


title:
Phase diagram for condensation of microcavity polaritons: from theory to
  practice

abstract:
  The first realization of a polariton condensate was recently achieved in a
CdTe microcavity [Kasprzak et al., Nature 443, 409 (2006)]. We compare the
experimental phase boundaries, for various detunings and cryostat temperatures,
with those found theoretically from a model which accounts for features of
microcavity polaritons such as reduced dimensionality, internal composite
structure, disorder in the quantum wells, polariton-polariton interactions, and
finite lifetime.


title: On the Mean-Field Limit of Bosons with Coulomb Two-Body Interaction

abstract:
  In the mean-field limit the dynamics of a quantum Bose gas is described by a
Hartree equation. We present a simple method for proving the convergence of the
microscopic quantum dynamics to the Hartree dynamics when the number of
particles becomes large and the strength of the two-body potential tends to 0
like the inverse of the particle number. Our method is applicable for a class
of singular interaction potentials including the Coulomb potential. We prove
and state our main result for the Heisenberg-picture dynamics of "observables",
thus avoiding the use of coherent states. Our formulation shows that the
mean-field limit is a "semi-classical" limit.


title: Balanced Families of Perfect Hash Functions and Their Applications

abstract:
  The construction of perfect hash functions is a well-studied topic. In this
paper, this concept is generalized with the following definition. We say that a
family of functions from $[n]$ to $[k]$ is a $\delta$-balanced $(n,k)$-family
of perfect hash functions if for every $S \subseteq [n]$, $|S|=k$, the number
of functions that are 1-1 on $S$ is between $T/\delta$ and $\delta T$ for some
constant $T>0$. The standard definition of a family of perfect hash functions
requires that there will be at least one function that is 1-1 on $S$, for each
$S$ of size $k$. In the new notion of balanced families, we require the number
of 1-1 functions to be almost the same (taking $\delta$ to be close to 1) for
every such $S$. Our main result is that for any constant $\delta > 1$, a
$\delta$-balanced $(n,k)$-family of perfect hash functions of size $2^{O(k \log
\log k)} \log n$ can be constructed in time $2^{O(k \log \log k)} n \log n$.
Using the technique of color-coding we can apply our explicit constructions to
devise approximation algorithms for various counting problems in graphs. In
particular, we exhibit a deterministic polynomial time algorithm for
approximating both the number of simple paths of length $k$ and the number of
simple cycles of size $k$ for any $k \leq O(\frac{\log n}{\log \log \log n})$
in a graph with $n$ vertices. The approximation is up to any fixed desirable
relative error.


title: Notes on quantum evolution across singularities

abstract:
  In a number of model contexts, evolution across space-time singularities
(reminiscent of the cosmological singularities) involves time-dependent quantum
Hamiltonians developing a singularity as a function of time. In this
contribution to the proceedings of the 3rd RTN workshop in Valencia, I review
some recent investigations of the general properties of such systems.


title: A comment on black hole state counting in loop quantum gravity

abstract:
  There are two ways of counting microscopic states of black holes in loop
quantum gravity, one counting all allowed spin network labels $j,m$ and the
other involving only the labels $m$. Counting states with $|m|=j$, as done in a
recent Letter, does not follow either.


title:
A Novel Quantum Transition in a Fully Frustrated Transverse Ising
  Antiferromagnet

abstract:
  We consider a long-range Ising antiferromagnet (LRIAF) put in a transverse
field. Applying quantum Monte Carlo method, we study the variation of order
parameter (spin correlation in Trotter time direction), susceptibility and
average energy of the system for various values of the transverse field at
different temperatures. The antiferromagnetic order is seen to get immediately
broken as soon as the thermal or quantum fluctuations are added. We also
discuss the phase diagram for the Sherrington-Kirkpatrick (SK) model with the
same LRIAF bias, also in presence of a transverse field. We find that while the
antiferromagnetic order is immediately broken as one adds an infinitesimal
transverse field or thermal fluctuation to the system, an infinitesimal SK spin
glass disorder is enough to induce a stable glass order in the antiferromagnet.
This glass order eventually gets destroyed as the thermal or quantum
fluctuations increased beyond their threshold values and the transition to para
phase occurs. Indications of this novel phase transition are discussed. Because
of the presence of full frustration, this surrogate property of the LRIAF for
incubation of stable spin glass phase in it (induced by addition of a small
disorder) should enable eventually the study of classical and quantum spin
glass phases by using some perturbation theory with respect to the disorder.


title:
Prospects for detection of the lunar Cerenkov emission by the UHE Cosmic
  Rays and Neutrinos using the GMRT and the Ooty Radio Telescope

abstract:
  Searching for the Ultra high energy Cosmic rays and Neutrinos of $> 10^{20}
eV$ is of great cosmological importance. A powerful technique is to search for
the \v{C}erenkov radio emission caused by UHECR or UHE neutrinos impinging on
the lunar regolith. We examine in this paper feasibility of detecting these
events by observing with the Giant Metrewave Radio Telescope (GMRT) which has a
large collecting area and operates over a wide frequency range with an
orthogonal polarisation capability. We discuss here prospects of observations
of the \v{C}erenkov radio emission with the GMRT at 140 MHZ with 32 MHz
bandwidth using the incoherent array and also forming 25 beams of the Central
Array to cover the moon. We also consider using the Ooty Radio Telescope (ORT)
which was specially designed in 1970 for tracking the Moon. With the ORT (530m
long and 30m wide parabolic cylinder) it becomes possible to track the Moon for
9.5 hours on a given day by a simple rotation along the long axis of the
parabolic cylinder. ORT operates at 325 MHz and has an effective collecting
area of ~ 8000 $m^2.$ Recently a digital system has been installed by
scientists of the Raman Research Institute (RRI), Bangalore and the Radio
Astronomy Centre (RAC) of NCRA/TIFR, at Ooty allowing a bandwidth of 10 MHz
with ~ 40 ns sampling. It is possible to form 6 beams covering the Moon and 7th
beam far away for discrimination of any terrestrial RFI. Increasing the
bandwidth of the existing 12 beam analogue system of the ORT from 4 MHz to 15
MHz to be sampled digitally is planned. It is shown that by observing the Moon
for $\ge$ 1000 hrs using the ORT it will provide appreciably higher sensitivity
than past searches made elsewhere. Using the GMRT and ORT, it may be possible
to reach sensitivity to test the Waxman-Bachall limit on UHE neutrino flux.


title:
Nickel-based phosphide superconductor with infinite-layer structure,
  BaNi2P2

abstract:
  Analogous to cuprate high-Tc superconductors, a NiP-based compound system has
several crystals in which the Ni-P layers have different stacking structures.
Herein, the properties of BaNi2P2 are reported. BaNi2P2 has an infinite-layer
structure, and shows a superconducting transition at ~3 K. Moreover, it
exhibits metallic conduction and Pauli paramagnetism in the temperature range
of 4-300 K. Below 3 K, the resistivity sharply drops to zero, and the magnetic
susceptibility becomes negative, while the volume fraction of the
superconducting phase estimated from the diamagnetic susceptibility reaches
~100 vol.% at 1.9 K. These observations substantiate that BaNi2P2 is a bulk
superconductor.


title: Gravitational instabilities in Kerr space-times

abstract:
  In this paper we consider the possible existence of unstable axisymmetric
modes in Kerr space times, resulting from exponentially growing solutions of
the Teukolsky equation. We describe a transformation that casts the radial
equation that results upon separation of variables in the Teukolsky equation,
in the form of a Schr\"odinger equation, and combine the properties of the
solutions of this equations with some recent results on the asymptotic
behaviour of spin weighted spheroidal harmonics to prove the existence of an
infinite family of unstable modes. Thus we prove that the stationary region
beyond a Kerr black hole inner horizon is unstable under gravitational linear
perturbations. We also prove that Kerr space-time with angular momentum larger
than its square mass, which has a naked singularity, is unstable.


title: Complex bodies with memory: linearized setting

abstract:
  The mechanics of complex bodies with memory effects is discussed in
linearized setting. The attention is focused on the characterization of free
energies in terms of minimum work and maximum recoverable work in the bulk and
along a discontinuity surface endowed with its own surface energy, a surface
internal to the body. To this aim, use is made of techniques proposed by Del
Piero. Consequences of the Clausius-Duhem inequality are investigated for
complex bodies with instantaneous linear elastic response.