title: On Yang-Mills Theories with Chiral Matter at Strong Coupling

abstract:
  Strong coupling dynamics of Yang--Mills theories with chiral fermion content
remained largely elusive despite much effort over the years. In this work, we
propose a dynamical framework in which we can address non-perturbative
properties of chiral, non-supersymmetric gauge theories, in particular, chiral
quiver theories on $S_1 \times R_3 $. Double-trace deformations are used to
stabilize the center-symmetric vacuum. This allows one to smoothly connect
small-$r(S_1)$ to large-$r(S_1)$ physics ($R_4$ is the limiting case) where the
double-trace deformations are switched off. In particular, occurrence of the
mass gap in the gauge sector and linear confinement due to bions are
analytically demonstrated. We find the pattern of the chiral symmetry
realization which depends on the structure of the ring operators, a novel class
of topological excitations. The deformed chiral theory, unlike the undeformed
one, satisfies volume independence down to arbitrarily small volumes (a working
Eguchi--Kawai reduction) in the large $N$ limit. This equivalence, may open new
perspectives on strong coupling chiral gauge theories on $R_4$.


title: Wet Paper Coding for Watermarking of Binary Images

abstract:
  We propose a new method to embed data in binary images, including scanned
text, figures, and signatures. Our method relies on the concept of wet paper
codes. The shuffling before embedding is used in order to equalize irregular
embedding capacity from diverse areas in the image. The hidden data can be
extracted without the original binary image. We illustrate some examples of
watermarked binary images after wet paper coding.


title: Commuting-Square Subfactors and Central Sequences

abstract:
  Let $M_0 \subset M_1$ be a finite-index infinite-depth hyperfinite $II_1$
subfactor and $\omega$ a free ultrafilter of the natural numbers. We show that
if this subfactor is constructed from a commuting square then the central
sequence inclusion $M_0^{\omega} \cap M_1' \subset (M_0)_{\omega}$ has infinite
Pimnser-Popa index. We will also demonstrate this result for certain
infinite-depth hyperfinite subfactors coming from groups.


title:
A Basic Thermodynamic Derivation of the Maximum Overburden Pressure
  Generated in Frost Heave

abstract:
  I describe a simple heat-engine derivation of the maximum overburden pressure
that can be generated in frost heave. The method stems from the fact that
useful work can, in principle, be extracted from the forces generated by an
advancing solidification front via the frost heave mechanism. Using an
idealized frost heave engine, together with the maximum thermodynamic
efficiency of any heat engine, one can derive the maximum overburden pressure.
A similar argument can also produce the maximum thermodynamic buoyancy force on
a foreign object within a solid surrounded by a premelted layer.


title: On S-Matrix factorization of the Landau-Lifshitz model

abstract:
  We consider the three-particle scattering S-matrix for the Landau-Lifshitz
model by directly computing the set of the Feynman diagrams up to the second
order. We show, following the analogous computations for the non-linear
Schr\"{o}dinger model, that the three-particle S-matrix is factorizable in the
first non-trivial order.


title: Evolution of a population of random Boolean networks

abstract:
  We investigate the evolution of populations of random Boolean networks under
selection for robustness of the dynamics with respect to the perturbation of
the state of a node. The fitness landscape contains a huge plateau of maximum
fitness that spans the entire network space. When selection is so strong that
it dominates over drift, the evolutionary process is accompanied by a slow
increase in the mean connectivity and a slow decrease in the mean fitness.
Populations evolved with higher mutation rates show a higher robustness under
mutations. This means that even though all the evolved populations exist close
to the plateau of maximum fitness, they end up in different regions of network
space.


title: The Dynamics of the One-Dimensional Delta-Function Bose Gas

abstract:
  We give a method to solve the time-dependent Schroedinger equation for a
system of one-dimensional bosons interacting via a repulsive delta function
potential. The method uses the ideas of Bethe Ansatz but does not use the
spectral theory of the associated Hamiltonian.


title:
Faranoff-Riley type I jet deceleration at density discontinuities
  "Relativistic hydrodynamics with realistic equation of state"

abstract:
  The deceleration mechanisms for relativistic jets in active galactic nuclei
remain an open question, and in this paper we propose a model which could
explain sudden jet deceleration, invoking density discontinuities. This is
particularly motivated by recent indications from HYMORS. Exploiting high
resolution, numerical simulations, we demonstrate that for both high and low
energy jets, always at high Lorentz factor, a transition to a higher density
environment can cause a significant fraction of the directed jet energy to be
lost on reflection. This can explain how one-sided jet deceleration and a
transition to FR I type can occur in HYMORS, which start as FR II (and remain
so on the other side). For that purpose, we implemented in the relativistic
hydrodynamic grid-adaptive AMRVAC code, the Synge-type equation of state
introduced in the general polytropic case by Meliani et al. (2004). We present
results for 10 model computations, varying the inlet Lorentz factor from 10 to
20, including uniform or decreasing density profiles, and allowing for
cylindrical versus conical jet models. As long as the jet propagates through
uniform media, we find that the density contrast sets most of the propagation
characteristics, fully consistent with previous modeling efforts. When the jet
runs into a denser medium, we find a clear distinction in the decelaration of
high energy jets depending on the encountered density jump. For fairly high
density contrast, the jet becomes destabilised and compressed, decelerates
strongly (up to subrelativistic speeds) and can form knots. We point out
differences that are found between cylindrical and conical jet models, together
with dynamical details like the Richtmyer-Meshkov instabilities developing at
the original contact interface.


title:
Galaxy density profiles and shapes -- I. simulation pipeline for lensing
  by realistic galaxy models

abstract:
  Studies of strong gravitational lensing in current and upcoming wide and deep
photometric surveys, and of stellar kinematics from (integral-field)
spectroscopy at increasing redshifts, promise to provide valuable constraints
on galaxy density profiles and shapes. However, both methods are affected by
various selection and modelling biases, whch we aim to investigate in a
consistent way. In this first paper in a series we develop a flexible but
efficient pipeline to simulate lensing by realistic galaxy models. These galaxy
models have separate stellar and dark matter components, each with a range of
density profiles and shapes representative of early-type, central galaxies
without significant contributions from other nearby galaxies. We use Fourier
methods to calculate the lensing properties of galaxies with arbitrary surface
density distributions, and Monte Carlo methods to compute lensing statistics
such as point-source lensing cross-sections. Incorporating a variety of
magnification bias modes lets us examine different survey limitations in image
resolution and flux. We rigorously test the numerical methods for systematic
errors and sensitivity to basic assumptions. We also determine the minimum
number of viewing angles that must be sampled in order to recover accurate
orientation-averaged lensing quantities. We find that for a range of
non-isothermal stellar and dark matter density profiles typical of elliptical
galaxies, the combined density profile and corresponding lensing properties are
surprisingly close to isothermal around the Einstein radius. The converse
implication is that constraints from strong lensing and/or stellar kinematics,
which are indeed consistent with isothermal models near the Einstein radius,
cannot trivially be extrapolated to smaller and larger radii.


title:
Orientational order in two dimensions from competing interactions at
  different scales

abstract:
  We discuss orientational order in two dimensions in the context of systems
with competing isotropic interactions at different scales. We consider an
extension of the Brazovskii model for stripe phases including explicitly
quartic terms with nematic symmetry in the energy. We show that leading
fluctuations of the mean field nematic solution drive the isotropic-nematic
transition into the Kosterlitz-Thouless universality class, i.e. these systems
have a thermodynamic phase with orientational quasi-long-range order.


title: Lieb-Robinson bounds and the speed of light from topological order

abstract:
  We apply the Lieb-Robinson bounds technique to find the maximum speed of
interaction in a spin model with topological order whose low-energy effective
theory describes light [see X.-G. Wen, \prb {\bf 68}, 115413 (2003)]. The
maximum speed of interactions is found in two dimensions is bounded from above
less than $\sqrt{2} e$ times the speed of emerging light, giving a strong
indication that light is indeed the maximum speed of interactions. This result
does not rely on mean field theoretic methods. In higher spatial dimensions,
the Lieb-Robinson speed is conjectured to increase linearly with the dimension
itself. Implications for the horizon problem in cosmology are discussed.


title: Rotations in the Space of Split Octonions

abstract:
  The geometrical application of split octonions is considered. The modified
Fano graphic, which represents products of the basis units of split octonionic,
having David's Star shape, is presented. It is shown that active and passive
transformations of coordinates in octonionic '8-space' are not equivalent. The
group of passive transformations that leave invariant the norm of split
octonions is SO(4,4), while active rotations is done by the direct product of
O(3,4)-boosts and real non-compact form of the exceptional group $G_2$. In
classical limit these transformations reduce to the standard Lorentz group.


title:
Galaxy density profiles and shapes -- II. selection biases in strong
  lensing surveys

abstract:
  [Abridged] Many current and future astronomical surveys will rely on samples
of strong gravitational lens systems to draw conclusions about galaxy mass
distributions. We use a new strong lensing pipeline (presented in Paper I of
this series) to explore selection biases that may cause the population of
strong lensing systems to differ from the general galaxy population. Our focus
is on point-source lensing by early-type galaxies with two mass components
(stellar and dark matter) that have a variety of density profiles and shapes
motivated by observational and theoretical studies of galaxy properties. We
seek not only to quantify but also to understand the physics behind selection
biases related to: galaxy mass, orientation and shape; dark matter profile
parameters such as inner slope and concentration; and adiabatic contraction. We
study how all of these properties affect the lensing Einstein radius, total
cross-section, quad/double ratio, and image separation distribution. We find
significant (factors of several) selection biases with mass; orientation, for a
given galaxy shape at fixed mass; cusped dark matter profile inner slope and
concentration; concentration of the stellar and dark matter deprojected Sersic
models. Interestingly, the intrinsic shape of a galaxy does not strongly
influence its lensing cross-section when we average over viewing angles. Our
results are an important first step towards understanding how strong lens
systems relate to the general galaxy population.


title: Vortex avalanches in the non-centrosymmetric superconductor Li2Pt3B

abstract:
  We investigated the vortex dynamics in the non-centrosymmetric superconductor
Li_2Pt_3B in the temperature range 0.1 K - 2.8 K. Two different logarithmic
creep regimes in the decay of the remanent magnetization from the Bean critical
state have been observed. In the first regime, the creep rate is
extraordinarily small, indicating the existence of a new, very effective
pinning mechanism. At a certain time a vortex avalanche occurs that increases
the logarithmic creep rate by a factor of about 5 to 10 depending on the
temperature. This may indicate that certain barriers against flux motion are
present and they can be opened under increased pressure exerted by the
vortices. A possible mechanism based on the barrier effect of twin boundaries
is briefly discussed.


title: Improved lower bound on the size of Kakeya sets over finite fields

abstract:
  In a recent breakthrough, Dvir showed that every Kakeya set in $\F^n$ must be
of cardinality at least $c_n |\F|^n$ where $c_n \approx 1/n!$. We improve this
lower bound to $\beta^n |\F|^n$ for a constant $\beta > 0$. This pins down the
growth of the leading constant to the right form as a function of $n$.


title:
Field Re-entrant Superconductivity Induced by the Enhancement of
  Effective Mass in URhGe

abstract:
  High quality single crystals of a ferromagnetic superconductor URhGe were
successfully grown. The electrical resistivity was measured for the field along
b-axis in the orthorhombic crystal structure in order to study precisely its
field re-entrant superconductivity which occurs in the vicinity of the field
$H_{\rm R}$, where the easy magnetization switches from $c$ to b-axis. The
field re-entrant superconductivity of URhGe is analyzed with special focus on
its dependence with the value of residual resistivity $\rho_0$ and the
coefficient $A$ of $T^2$ term of the resistivity. The experimental results are
well explained by a crude model related with the field dependence of the
effective mass $m^\ast$, where the corresponding critical temperature
$T_{\mathrm{sc}}(m^\ast)$ and the upper critical field $H_{\rm c2}$ are
strongly enhanced. Discussion is made on the interplay between magnetic and
superconducting phase diagram as well as the link between $T_{\mathrm{sc}}$ and
$A$ in other heavy fermion superconductors.


title: Extending Hudson's theorem to mixed quantum states

abstract:
  According to Hudson's theorem, any pure quantum state with a positive Wigner
function is necessarily a Gaussian state. Here, we make a step towards the
extension of this theorem to mixed quantum states by finding upper and lower
bounds on the degree of non-Gaussianity of states with positive Wigner
functions. The bounds are expressed in the form of parametric functions
relating the degree of non-Gaussianity of a state, its purity, and the purity
of the Gaussian state characterized by the same covariance matrix. Although our
bounds are not tight, they permit us to visualize the set of states with
positive Wigner functions.


title:
The Conjugacy Problem in the Grigorchuk Group is polynomial time
  decidable

abstract:
  In this paper we prove that the Conjugacy Problem in the Grigorchuk group
$\Gamma$ has polynomial time complexity.


title: Three-dimensional N=6 SCFT's and their membrane dynamics

abstract:
  We analyze several aspects of the recent construction of three-dimensional
conformal gauge theories by Aharony et al. in various regimes. We pay special
attention to understanding how the M-theory geometry and interpretation can be
extracted from the analysis of the field theory. We revisit the calculations of
the moduli space of vacua and the complete characterization of chiral ring
operators by analyzing the field theory compactified on a 2-sphere. We show
that many of the states dual to these operators can be interpreted as D-brane
states in the weak coupling limit. Also, various features of the dual AdS
geometry can be obtained by performing a strong coupling expansion around
moduli space configurations, even though one is not taking the planar
expansion. In particular, we show that at strong coupling the corresponding
weak coupling D-brane states of the chiral ring localize on particular
submanifolds of the dual geometry that match the M-theory interpretation. We
also study the massive spectrum of fields in the moduli space. We use this to
investigate the dispersion relation of giant magnons from the field theory
point of view. Our analysis predicts the exact functional form of the
dispersion relation as a function of the world-sheet momentum, independently of
integrability assumptions, but not the exact form with respect to the 't Hooft
coupling. We also get the dispersion relation of bound states of giant magnons
from first principles, providing evidence for the full integrability of the
corresponding spin chain model at strong 't Hooft coupling.


title: Non-Gaussian continuous-variable teleportation

abstract:
  We have recently shown that the output field in the Braunstein-Kimble
protocol of teleportation is a superposition of two fields: the input one and a
field created by Alice's measurement and by displacement of the state at Bob's
station by using the classical information provided by Alice. We study here the
noise added by teleportation and compare its influence in the Gaussian and
non-Gaussian settings.


title:
Heavy element abundances in giant stars of the globular clusters M4 and
  M5

abstract:
  We present a comprehensive abundance analysis of 27 heavy elements in bright
giant stars of the globular clusters M4 and M5 based on high resolution, high
signal-to-noise ratio spectra obtained with the Magellan Clay Telescope. We
confirm and expand upon previous results for these clusters by showing that (1)
all elements heavier than, and including, Si have constant abundances within
each cluster, (2) the elements from Ca to Ni have indistinguishable
compositions in M4 and M5, (3) Si, Cu, Zn, and all s-process elements are
approximately 0.3 dex overabundant in M4 relative to M5, and (4) the r-process
elements Sm, Eu, Gd, and Th are slightly overabundant in M5 relative to M4. The
cluster-to-cluster abundance differences for Cu and Zn are intriguing,
especially in light of their uncertain nucleosynthetic origins. We confirm that
stars other than Type Ia supernovae must produce significant amounts of Cu and
Zn at or below the clusters' metallicities. If intermediate-mass AGB stars or
massive stars are responsible for the Cu and Zn enhancements in M4, the similar
[Rb/Zr] ratios and (preliminary) Mg isotope ratios in both clusters may be
problematic for either scenario. For the elements from Ba to Hf, we assume that
the s- and r-process contributions are scaled versions of the solar s- and
r-process abundances. We quantify the relative fractions of s- and r-process
material for each cluster and show that they provide an excellent fit to the
observed abundances.


title: Telescopes versus Microscopes: the puzzle of Iron-60

abstract:
  The discovery that the short-lived radionucleide iron-60 was present in the
oldest meteorites suggests that the formation of the Earth closely followed the
death of a massive star. I discuss three astrophysical origins: winds from an
AGB star, injection of supernova ejecta into circumstellar disks, and induced
star formation on the boundaries of HII regions. I show that the first two fail
to match the solar system iron-60 abundance in the vast majority of star
forming systems. The cores and pillars on the edges of HII regions are
spectacular but rare sites of star formation and larger clumps with masses
1e3-1e4 solar masses at tens of parsec from a supernova are a more likely birth
environment for our Sun. I also examine gamma-ray observations of iron-60 decay
and show that the Galactic background could account for the low end of the
range of meteoritic measurements if the massive star formation rate was at
least a factor of 2 higher 4.6 Gyr ago.


title: Remarks on Chern-Simons Theory

abstract:
  In the late 1980s Witten used the Chern-Simons form of a connection to
construct new invariants of 3-manifolds and knots, recovering in particular the
Jones invariants. Since then the associated topological quantum field theory
(TQFT) has served as a key example in understanding the structure of TQFTs in
general. We survey some of that structure with a particular focus on the
"multi-tier" aspects. We discuss general axioms, generators-and-relations
theorems, a priori constructions, dimensional reduction and K-theory, and
Chern-Simons as a 0-1-2-3 theory. An appendix gives a lightening treatment of
the Chern-Simons-Weil theory of connections. The paper concludes with general
remarks about the Geometry-QFT-Strings interaction.


title:
Infrared behaviour of the fermion propagator in unquenched QED$_3$ with
  finite threshold effects

abstract:
  To remove the linear infrared divergences in quenched approximation we
include the massive fermion loop to the photon spectral function.Spectral
function of fermion has no one particle singularity if we fix the anomalous
dimension to be unity.In the case of $N$ flavour,$N$ dependence of order
parameter is mild which may be due to screening effects.


title: A light CP-odd Higgs boson and the muon anomalous magnetic moment

abstract:
  We amalgamate the many experimental limits on the $ab\anti b$ coupling of a
light CP-odd Higgs boson, $a$, including model-dependence coming from the ratio
of the $at\anti t$ to the $a b\anti b$ coupling. We then employ these limits to
analyze the extent to which a light $a$ can make a significant contribution to
the discrepancy, $\Delta a_\mu$, between the experimentally observed $a_\mu$
and that predicted by the standard model. In a "model-independent" framework
and in the context of a general two-Higgs-doublet model this is a significant
possibility. In contrast, the minimal supersymmetric model is too strongly
constrained (after combining experimental and theoretical input) to allow a
CP-odd-$a$ explanation of $\Delta a_\mu$. The next-to-minimal supersymmetric
model allows more freedom and the light $a$ of the model could explain the full
$\Delta a_\mu$ if $9.2\gev<\ma<12\gev $, or contribute substantially for larger
$\ma$, if $\tanb$ is large.


title: Post-Newtonian Approximation in Maxwell-Like Form

abstract:
  The equations of the linearized first post-Newtonian approximation to general
relativity are often written in "gravitoelectromagnetic" Maxwell-like form,
since that facilitates physical intuition. Damour, Soffel and Xu (DSX) (as a
side issue in their complex but elegant papers on relativistic celestial
mechanics) have expressed the first post-Newtonian approximation, including all
nonlinearities, in Maxwell-like form. This paper summarizes that DSX
Maxwell-like formalism (which is not easily extracted from their celestial
mechanics papers), and then extends it to include the post-Newtonian
(Landau-Lifshitz-based) gravitational momentum density, momentum flux (i.e.
gravitational stress tensor) and law of momentum conservation in Maxwell-like
form. The authors and their colleagues have found these Maxwell-like momentum
tools useful for developing physical intuition into numerical-relativity
simulations of compact binaries with spin.


title: Adsorbate-limited conductivity of graphene

abstract:
  We present a theory of electronic transport in graphene in the presence of
randomly placed adsorbates. Our analysis predicts a marked asymmetry of the
conductivity about the Dirac point, as well as a negative weak-localization
magnetoresistivity. In the region of strong scattering, renormalization group
corrections drive the system further towards insulating behavior. These results
explain key features of recent experiments, and are validated by numerical
transport computations.


title: Study of highly-excited string states at the Large Hadron Collider

abstract:
  In TeV-scale gravity scenarios with large extra dimensions, black holes may
be produced at future colliders. Good arguments have been made for why general
relativistic black holes may be just out of reach of the Large Hadron Collider
(LHC). However, in weakly-coupled string theory, highly excited string states -
string balls - could be produced at the LHC with high rates and decay
thermally, not unlike general relativistic black holes. In this paper, we
simulate and study string ball production and decay at the LHC. We specifically
emphasize the experimentally-detectable similarities and differences between
string balls and general relativistic black holes at a TeV scale.


title:
Noise-Sustained Convective Instability in a Magnetized Taylor-Couette
  Flow

abstract:
  The helical magnetorotational instability of the magnetized Taylor-Couette
flow is studied numerically in a finite cylinder. A distant upstream insulating
boundary is shown to stabilize the convective instability entirely while
reducing the growth rate of the absolute instability. The reduction is less
severe with larger height. After modeling the boundary conditions properly, the
wave patterns observed in the experiment turn out to be a noise-sustained
convective instability. After the source of the noise resulted from unstable
Ekman and Stewartson layers is switched off, a slowly-decaying inertial
oscillation is observed in the simulation. We reach the conclusion that the
experiments completed to date have not yet reached the regime of absolute
instability.


title: Noise-based communication and computing

abstract:
  We discuss the speed-error-heat triangle and related problems with rapidly
increasing energy dissipation and error rate during miniaturization. These and
the independently growing need of unconditional data security have provoked
non-conventional approaches in the physics of informatics. Noise-based
informatics is a potentially promising possibility which is the way how
biological brains process the information. Recently, it has been shown that
thermal noise and its electronically enhanced versions (Johnson-like noises)
can be utilized as information carrier with peculiar properties. Relevant
examples are Zero power (stealth) communication, Unconditionally secure
communication with Johnson(-like) noise and Kirchhoff loop and Noise-driven
computing. The zero power communication utilizes the equilibrium background
noise in the channel to transfer information. The unconditionally secure
communication is based on the properties of Johnson(-like) noise and those of a
simple Kirchhoff's loop. The scheme utilizes on the robustness of classical
information and the second law of thermodynamics. It uncovers active
eavesdropping within a single clock period (no error statistics is required)
and it is naturally protected against the man-in-the-middle attack. Further
advantages of the scheme is that the circuitry can easily be integrated on
computer chips, unconditionally secure computer processors, memories and other
hardware can be realized.


title:
Provably efficient instanton search algorithm for LP decoding of LDPC
  codes over the BSC

abstract:
  We consider Linear Programming (LP) decoding of a fixed Low-Density
Parity-Check (LDPC) code over the Binary Symmetric Channel (BSC). The LP
decoder fails when it outputs a pseudo-codeword which is not a codeword. We
design an efficient algorithm termed the Instanton Search Algorithm (ISA)
which, given a random input, generates a set of flips called the BSC-instanton.
We prove that: (a) the LP decoder fails for any set of flips with support
vector including an instanton; (b) for any input, the algorithm outputs an
instanton in the number of steps upper-bounded by twice the number of flips in
the input. Repeated sufficient number of times, the ISA outcomes the number of
unique instantons of different sizes.


title: Transmission probabilities and the Miller-Good transformation

abstract:
  Transmission through a potential barrier, and the related issue of particle
production from a parametric resonance, are topics of considerable general
interest in quantum physics. The authors have developed a rather general bound
on quantum transmission probabilities, and recently applied it to bounding the
greybody factors of a Schwarzschild black hole. In the current article we take
a different tack -- we use the Miller-Good transformation (which maps an
initial Schrodinger equation to a final Schrodinger equation for a different
potential) to significantly generalize the previous bound.


title:
Why it has become more difficult to predict Nobel Prize winners: a
  bibliometric analysis of Nominees and Winners of the Chemistry and Physics
  Prizes (1901-2007)

abstract:
  We propose a comprehensive bibliometric study of the profile of Nobel
prizewinners in chemistry and physics from 1901 to 2007, based on citation data
available over the same period. The data allows us to observe the evolution of
the profiles of winners in the years leading up to (and following) nominations
and awarding of the Nobel Prize. The degree centrality and citation rankings in
these fields confirm that the Prize is awarded at the peak of the winners'
careers, despite brief a Halo Effect observable in the years following the
attribution of the Prize. Changes in the size and organization of the two
fields result in a rapid decline of predictive power of bibliometric data over
the century. This can be explained not only by the growing size and
fragmentation of the two disciplines, but also, at least in the case of
physics, by an implicit hierarchy in the most legitimate topics within the
discipline, as well as among the scientists selected for the Prize.
Furthermore, the lack of readily-identifiable dominant contemporary physicists
suggests that there are few new paradigm shifts within the field, as perceived
by the scientific community as a whole.


title: Comment on "Black hole constraints on varying fundamental constants"

abstract:
  In the Letter [1] (also [2]) there is a claim that the generalised second law
of thermodynamics (entropy increase) for black holes provides some limits on
the rate of variation of the fundamental constants of nature (electric charge
e, speed of light c, etc.). We have come to a different conclusion. The results
in [1,2] are based on assumption that mass of a black hole does not change
without radiation and accreation. We present arguments showing that this
assumption is incorrect and give an estimate of the black hole mass variation
due to alpha=e^2/\hbar c variation using entropy (and quantum energy level)
conservation in an adiabatic process. No model-independent limits on the
variation of the fundamental constants are derived from the second law of
thermodynamics.

categories: gr-qc astro-ph hep-ph hep-th physics.atom-ph


title:
The B -> D* l nu form factor at zero recoil from three-flavor lattice
  QCD: A model independent determination of |V_cb|

abstract:
  We present the first lattice QCD calculation of the form factor for B-> D* l
nu with three flavors of sea quarks. We use an improved staggered action for
the light valence and sea quarks (the MILC configurations), and the Fermilab
action for the heavy quarks. The form factor is computed at zero recoil using a
new double ratio method that yields the form factor more directly than the
previous Fermilab method. Other improvements over the previous calculation
include the use of much lighter light quark masses, and the use of lattice
(staggered) chiral perturbation theory in order to control the light quark
discretization errors and chiral extrapolation. We obtain for the form factor,
F_{B-> D*}(1)=0.921(13)(20), where the first error is statistical and the
second is the sum of all systematic errors in quadrature. Applying a 0.7%
electromagnetic correction and taking the latest PDG average for F_{B->
D*}(1)|V_cb| leads to |V_cb|=(38.7 +/- 0.9_exp +/- 1.0_theo) x 10^-3.


title:
SUSY/Non-SUSY Duality in U(N) Gauge Model with Partially Broken N=2
  Supersymmetry

abstract:
  We study the vacuum structure of the U(N) gauge model with partially broken
N=2 supersymmetry. From the analysis of the classical vacua of this model, we
point out that in addition to the ordinary N=1 supersymmetric vacua, there are
vacua with negative gauge coupling constants, which preserve another N=1
supersymmetry. These latter vacua can be analyzed by using SUSY/non-SUSY
duality which is recently proposed by Aganagic, Beem, Seo and Vafa. A dual
description of these in UV is U(N) gauge theory where the supersymmetry is
broken by spurion superfields. Following them, we see that there are
supersymmetry preserving vacua as well as supersymmetry breaking vacua of low
energy effective theory.


title: An observation about submatrices

abstract:
  Let M be an arbitrary Hermitian matrix of order n, and k be a positive
integer less than or equal to n. We show that if k is large, the distribution
of eigenvalues on the real line is almost the same for almost all principal
submatrices of M of order k. The proof uses results about random walks on
symmetric groups and concentration of measure. In a similar way, we also show
that almost all k x n submatrices of M have almost the same distribution of
singular values.


title: Unification theorems in algebraic geometry

abstract:
  In this paper, for a given finitely generated algebra (an algebraic structure
with arbitrary operations and no predicates) A we study finitely generated
limit algebras of A, approaching them via model theory and algebraic geometry.
Along the way we lay down foundations of algebraic geometry over arbitrary
algebraic structures.


title:
Density functional with full exact exchange, balanced nonlocality of
  correlation, and constraint satisfaction

abstract:
  We construct a nonlocal density functional approximation with full exact
exchange, while preserving the constraint-satisfaction approach and justified
error cancellations of simpler semilocal functionals. This is achieved by
interpolating between different approximations suitable for two extreme regions
of the electron density. "Normal" regions are well described by semilocal
approximations, because of proper accuracy for a slowly-varying density or
because of error cancellation between exchange and correlation. "Abnormal"
regions, where nonlocality is unveiled, include those in which exchange can
dominate correlation (one-electron, nonuniform high-density, and
rapidly-varying limits), and those open subsystems of fluctuating electron
number over which the exact exchange-correlation hole integrates to a value
greater than -1. Regions between these extremes are described by a hybrid
functional mixing exact and semilocal exchange energy densities locally.
Because our mixing fraction tends to 1 in the high-density limit, we rigorously
employ full exact exchange. However, the nonlocality of exchange also requires
balanced nonlocality of correlation, which can demand at least five empirical
parameters. Our local hybrid functional is perhaps the first size-consistent
fourth-rung density functional or hyper-GGA with full exact exchange, is exact
for all one-electron densities, and provides an excellent fit to the 223
molecular enthalpies of formation of the G3/99 set and the 42 reaction barrier
heights of the BH42/03 set, improving both (but especially the latter) over
most semilocal functionals and global hybrids.


title: A Geometrical Approach to Hilbert-Schmidt Operators

abstract:
  We give a Riemannian structure to the set $\Sigma$ of positive invertible
unitized Hilbert-Schmidt operators, by means of the trace inner product. This
metric makes of $\Sigma$ a nonpositively curved, simply connected and
metrically complete Hilbert manifold. The manifold $\Sigma$ is a universal
model for symmetric spaces of the noncompact type: any such space can be
isometrically embedded into $\Sigma$. We give an intrinsic algebraic
characterization of convex closed submanifolds $M$. We study the group of
isometries of such submanifolds: we prove that $G_M$, the Banach-Lie group
generated by $M$, acts isometrically and transitively on $M$. Moreover, $G_M$
admits a polar decomposition relative to $M$, namely $G_M\simeq M\times K$ as
Hilbert manifolds (here $K$ is the isotropy of $p=1$ for the action $I_g:
p\mapsto gpg^*$), and also $G_M/K\simeq M$ so $M$ is an homogeneous space. We
obtain several decomposition theorems by means of geodesically convex
submanifolds $M$. These decompositions are obtained \textit{via} a nonlinear
but analytic orthogonal projection $\Pi_M:\Sigma\to M$, a map which is a
contraction for the geodesic distance. As a byproduct, we prove the isomorphism
$NM\simeq\Sigma$ (here $NM$ stands for the normal bundle of a convex closed
submanifold $M$). Writing down the factorizations for fixed ${\rm e}^a$, we
obtain ${\rm e}^a={\rm e}^x{\rm e}^v{\rm e}^x$ with ${\rm e}^x\in M$ and $v$
orthogonal to $M$ at $p=1$. As a corollary we obtain decompositions for the
full group of invertible elements $G\simeq M\times \exp(T_1M^{\perp})\times K$.


title: Hopf-Rinow Theorem in the Sato Grassmannian

abstract:
  Let $U_2({\cal H})$ be the Banach-Lie group of unitary operators in the
Hilbert space ${\cal H}$ which are Hilbert-Schmidt perturbations of the
identity 1. In this paper we study the geometry of the unitary orbit $$\{upu^*:
u\in U_2({\cal H})\},$$ of an infinite projection $p$ in ${\cal H}$. This orbit
coincides with the connected component of $p$ in the Hilbert-Schmidt restricted
Grassmannian $Gr_{res}(p)$ (also known in the literature as the Sato
Grassmannian) corresponding to the polarization ${\cal H}=p({\cal H})\oplus
p({\cal H})^\perp$. It is known that the components of $Gr_{res}(p)$ are
differentiable manifolds. Here we give a simple proof of the fact that
$Gr_{res}^0(p)$ is a smooth submanifold of the affine Hilbert space $p+{\cal
B}_2({\cal H})$, where ${\cal B}_2({\cal H})$ denotes the space of
Hilbert-Schmidt operators of ${\cal H}$. We prove that the geodesics of the
natural connection, which are of the form $\gamma(t)=e^{tz}pe^{-tz}$, for $z$ a
$p$-codiagonal anti-hermitic element of ${\cal B}_2({\cal H})$, have minimal
length provided that $\|z\|\le \pi/2$. Note that the condition is given in
terms of the usual operator norm, a fact which implies that there exist minimal
geodesics of arbitrary length. Also we show that any two points $p_1,p_2\in
Gr_{res}^0(p)$ are joined by a minimal geodesic. If moreover $\|p_1-p_2\|<1$,
the minimal geodesic is unique. Finally, we replace the 2-norm by the
$k$-Schatten norm ($k>2$), and prove that the geodesics are also minimal for
these norms, up to a critical value of $t$, which is estimated also in terms of
the usual operator norm. In the process, minimality results in the $k$-norms
are also obtained for the group $U_2({\cal H})$.


title:
The subhalo - satellite connection and the fate of disrupted satellite
  galaxies

abstract:
  In the standard paradigm, satellite galaxies are believed to be associated
with the population of dark matter subhalos. In this paper, we use the
conditional stellar mass functions of {\it satellite galaxies} obtained from a
large galaxy group catalogue together with models of the subhalo mass functions
to explore the fraction and fate of stripped stars from satellites in galaxy
groups and clusters of different masses. The majority of the stripped stars in
massive halos are predicted to end up as intra-cluster stars, and the predicted
amounts of the intra-cluster component as a function of the velocity dispersion
of galaxy system match well the observational results obtained by Gonzalez et
al. (2007). The fraction of the mass in the stripped stars to that remain bound
in the central and satellite galaxies is the highest ($\sim 40%$ of the total
stellar mass) in halos with masses $M_h\sim 10^{14}\msunh$. If all these stars
end up in the intra-cluster component (Max), or maximum of them are accreted
into the central galaxy (Min), then we can predict that a maximum $\sim 19%$
and a minimum $\sim 5%$ of the total stars in the whole universe are in terms
of the diffused intra-cluster component. In the former case, in massive halos
with $M_h \sim 10^{15} \msunh$, the stellar mass of the intra-cluster component
is roughly 6 times as large as that of the central galaxy. This factor
decreases to $\sim 2$, 1 and 0.1 in halos with $M_h \sim 10^{14}$, $10^{13}$,
and $10^{12} \msunh$, respectively. The total amount of stars stripped from
satellite galaxies is insufficient to build up the central galaxies in halos
with masses $\la 10^{12.5}\msunh$, and so the quenching of star formation must
occur in halos with higher masses. Abridged.


title: Weak Riemannian manifolds from finite index subfactors

abstract:
  Let $N\subset M$ be a finite Jones' index inclusion of II$_1$ factors, and
denote by $U_N\subset U_M$ their unitary groups. In this paper we study the
homogeneous space $U_M/U_N$, which is a (infinite dimensional) differentiable
manifold, diffeomorphic to the orbit $$ {\cal O}(p) =\{u p u^*: u\in U_M\} $$
of the Jones projection $p$ of the inclusion. We endow ${\cal O}(p) $ with a
Riemannian metric, by means of the trace on each tangent space. These are
pre-Hilbert spaces (the tangent spaces are not complete), therefore ${\cal
O}(p)$ is a weak Riemannian manifold. We show that ${\cal O}(p)$ enjoys certain
properties similar to classic Hilbert-Riemann manifolds. Among them, metric
completeness of the geodesic distance, uniqueness of geodesics of the
Levi-Civita connection as minimal curves, and partial results on the existence
of minimal geodesics. For instance, around each point $p_1$ of ${\cal O}(p)$,
there is a ball $\{q\in {\cal O}(p):\|q-p_1\|<r\}$ (of uniform radius $r$) of
the usual norm of $M$, such that any point $p_2$ in the ball is joined to $p_1$
by a unique geodesic, which is shorter than any other piecewise smooth curve
lying inside this ball. We also give an intrinsic (algebraic) characterization
of the directions of degeneracy of the submanifold inclusion ${\cal
O}(p)\subset {\cal P}(M_1)$, where the last set denotes the Grassmann manifold
of the von Neumann algebra generated by $M$ and $p$.


title: On Integral Operators with Operator Valued Kernels

abstract:
  Here Lq-Lp boundedness of integral operator with operator-valued kernels is
studied and the main result is applied to convolution operators. Using these
results Besov space regularity for Fourier multiplier operator is established.


title:
Deep Near-IR Surface Photometry of 57 Galaxies in the Local Sphere of
  Influence

abstract:
  We present H-band surface photometry of 57 galaxies drawn from the Local
Sphere of Influence (LSI) with distances of less than 10 Mpc from the Milky
Way. The images with a typical surface brightness limit 4 mag fainter than
2MASS (24.5 mag arcsec^-2 < sb_lim < 26 mag arcsec ^-2) have been obtained with
IRIS2 on the 3.9 m Anglo-Australian Telescope. A total of 22 galaxies that
remained previously undetected in the near-IR and potentially could have been
genuinely young galaxies were found to have an old stellar population with a
star density 1-2 magnitudes below the 2MASS detection threshold. The cleaned
near-IR images reveal the morphology and extent of many of the galaxies for the
first time. For all program galaxies, we derive radial luminosity profiles,
ellipticities, and position angles, together with global parameters such as
total magnitude, mean effective surface brightness and half-light radius. Our
results show that 2MASS underestimates the total magnitude of galaxies with
<mu_H>_eff between 18-21 mag arcsec^-2 by up to 2.5 mag. The Sersic parameters
best describing the observed surface brightness profiles are also presented.
Adopting accurate galaxy distances and a H-band mass-to-light ratio of
Upsilon_H=1.0 +/- 0.4, the LSI galaxies are found to cover a stellar mass range
of 5.6 < log_10 (M_stars) < 11.1. The results are discussed along with
previously obtained optical data. Our sample of low luminosity galaxies is
found to follow closely the optical-infrared B versus H luminosity relation
defined by brighter galaxies with a slope of 1.14 +/- 0.02 and scatter of 0.3
magnitudes. Finally we analyse the luminosity - surface brightness relation to
determine an empirical mass-to-light ratio of Upsilon_H=0.78 +/- 0.08 for
late-type galaxies in the H-band.


title: Fair Scheduling in Networks Through Packet Election

abstract:
  We consider the problem of designing a fair scheduling algorithm for
discrete-time constrained queuing networks. Each queue has dedicated exogenous
packet arrivals. There are constraints on which queues can be served
simultaneously. This model effectively describes important special instances
like network switches, interference in wireless networks, bandwidth sharing for
congestion control and traffic scheduling in road roundabouts. Fair scheduling
is required because it provides isolation to different traffic flows; isolation
makes the system more robust and enables providing quality of service. Existing
work on fairness for constrained networks concentrates on flow based fairness.
As a main result, we describe a notion of packet based fairness by establishing
an analogy with the ranked election problem: packets are voters, schedules are
candidates and each packet ranks the schedules based on its priorities. We then
obtain a scheduling algorithm that achieves the described notion of fairness by
drawing upon the seminal work of Goodman and Markowitz (1952). This yields the
familiar Maximum Weight (MW) style algorithm. As another important result we
prove that algorithm obtained is throughput optimal. There is no reason a
priori why this should be true, and the proof requires non-traditional methods.


title:
Quantum memory for light using extended atomic ensembles in a tunable
  cavity

abstract:
  Cavity-assisted storage and retrieval of single-photon wave packets in
optically thin spatially extended resonant materials are analyzed. It is shown
that the use of cavity tuning allows one to store and recall time-symmetric
double-sided exponential pulses with near unit efficiency. The optimal regime
of the cavity tuning is determined and the effect of time jitter on the storage
efficiency is analyzed.


title: Sensitivity of PDR Calculations to Microphysical Details

abstract:
  Our understanding of physical processes in Photodissociation regions or
Photon Dominated Regions (PDRs) largely depends on the ability of spectral
synthesis codes to reproduce the observed infrared emission-line spectrum. In
this paper, we explore the sensitivity of a single PDR model to microphysical
details. Our calculations use the Cloudy spectral synthesis code, recently
modified to include a wealth of PDR physical processes. We show how the
chemical/thermal structure of a PDR, along with the calculated spectrum,
changes when the treatment of physical processes such as grain physics and
atomic/molecular rates are varied. We find a significant variation in the
intensities of PDR emission lines, depending on different treatments of the
grain physics. We also show how different combinations of the cosmic-ray
ionization rate, inclusion of grain-atom/ion charge transfer, and the grain
size distribution can lead to very similar results for the chemical structure.
Additionally, our results show the utility of Cloudy for the spectral modeling
of molecular environments.


title: Quantum tetrahedron and its classical limit

abstract:
  We present an asymptotically optimal generalized measurement for the
Classical information that is retrieved from a quantum tetrahedron is
intrinsically fuzzy. We present an asymptotically optimal generalized
measurement for the extraction of classical information from a quantum
tetrahedron. For a single tetrahedron the optimal uncertainty in dihedral
angles is shown to scale as an inverse of the surface area. Having commutative
observables allows to show how the clustering of many small tetrahedra leads to
a faster convergence to a classical geometry.


title:
The AAT/WFI survey of the Monoceros Ring and Canis Major Dwarf galaxy:
  II. from l = (280 - 025)deg

abstract:
  This paper concludes a systematic search for evidence of the Monoceros Ring
and Canis Major dwarf galaxy around the Galactic Plane. Presented here are the
results for the Galactic longitude range of l = (280 - 025)deg. Testing the
claim that the Monoceros Ring encircles the entire Galaxy, this survey attempts
to document the position of the Monoceros Ring with increasing Galactic
longitude. Additionally, with the discovery of the purported Canis Major dwarf
galaxy, searching for more evidence of its interaction is imperative to tracing
its path through the Galaxy and understanding its role in the evolution of the
Milky Way. Two new detections of the Monoceros Ring have been found at (l, b) =
(280,+15)deg and (300,+10)deg. Interestingly, in general there seem to be more
detections above the Plane than below it; in this survey around 2/3 of the firm
Monoceros Ring detections are in the North. This coincides with the Northern
detections appearing to be qualitatively denser and broader than their Southern
counterparts. The maximum of the Galactic Warp in the South is also probed in
this survey. It is found that these fields do not resemble those in the Canis
Major region suggesting that the Warp does not change the shape of the CMD as
is witnessed around Canis Major. The origins and morphology of the Monoceros
Ring is still elusive primarily due to its enormous extent on the sky.
Continued probing of the Galactic Outer Disc is needed before a consensus can
be reached on its nature.


title:
High Kondo temperature (TK ~ 80 K) in self-assembled InAs quantum dots
  laterally coupled to nanogap electrodes

abstract:
  We have fabricated single electron tunneling structures by forming nanogap
metallic electrodes directly upon single self-assembled InAs quantum dots
(QDs). The fabricated samples exhibited clear Coulomb blockade effects.
Furthermore, a clear Kondo effect was observed when strong coupling between the
electrodes and the QDs was realized using a large QD with a diameter of ~ 100
nm. From the temperature dependence of the linear conductance at the Kondo
valley, the Kondo temperature TK was determined to be ~ 81 K. This is the
highest TK ever reported for artificial quantum nanostructures.


title:
Lighthouses with two lights: burst oscillations from the
  accretion-powered millisecond pulsars

abstract:
  The key contribution of the discovery of nuclear-powered pulsations from the
accretion-powered millisecond pulsars (AMPs) has been the establishment of
burst oscillation frequency as a reliable proxy for stellar spin rate. This has
doubled the sample of rapidly-rotating accreting neutron stars and revealed the
unexpected absence of any stars rotating near the break-up limit. The resulting
`braking problem' is now a major concern for theorists, particularly given the
possible role of gravitational wave emission in limiting spin. This, however,
is not the only area where burst oscillations from the AMPs are having an
impact. Burst oscillation timing is developing into a promising technique for
verifying the level of spin variability in the AMPs (a topic of considerable
debate). These sources also provide unique input to our efforts to understand
the still-elusive burst oscillation mechanism. This is because they are the
only stars where we can reliably gauge the role of uneven fuel deposition and,
of course, the magnetic field.


title: Ekedahl-Oort strata and Kottwitz-Rapoport strata

abstract:
  We study the moduli space A_g of g-dimensional principally polarized abelian
varieties in positive characteristic, and its variant A_I with Iwahori level
structure. Both supersingular Ekedahl-Oort strata and supersingular
Kottwitz-Rapoport strata are isomorphic to disjoint unions of Deligne-Lusztig
varieties (see [Hoeve 2008] and [Goertz, Yu 2008], resp.). Here we compare
these isomorphisms. We also give an explicit description of Kottwitz-Rapoport
strata contained in the supersingular locus in the general parahoric case.
Finally, we show that every Ekedahl-Oort stratum is isomorphic to a parahoric
Kottwitz-Rapoport stratum.


title: Vafa-Witten Theory on N=2 and N=4 Twisted Superspace in Four Dimensions

abstract:
  We construct a new off-shell twisted hypermultiplet with a scalar and an
anti-self-dual tensor superfields. Using the N=2 twisted superspace formalism,
we construct a Donaldson-Witten theory coupled to the hypermultiplet. We show
that this action possesses the Vafa-Witten type N=4 twisted supersymmetry at
the on-shell level. We also reconstruct the action using a N=4 twisted
superconnection formalism.


title: Microlensing Optical Depth Revisited with Recent Star Counts

abstract:
  More reliable constraints on the microlensing optical depth comes from a
better understanding of the Galactic model. Based on well-constrained Galactic
bulge and disk models constructed from survey observations, such as, HST,
2MASS, and SDSS, we calculate the microlensing optical depths toward the
Galactic bulge fields, and compare them with recent results of microlensing
surveys. We test chi^2 statistics of microlensing optical depths expected from
those models, as well as previously proposed models, using two types of data:
optical depth map in (l, b) and averaged optical depth over the Galactic
longitude l as a function of the latitude b. From this analysis, we find that
the Galactic bulge models of 2MASS, Han & Gould (2003), and G2 of Stanek et al.
(1997) show a good agreement with the microlensing optical depth profiles for
all the microlensing observations, compared with E2 of Stanek et al. (1997). We
find, on the other hand, that models involving an SDSS disk model produce
relatively higher chi^2 values. It should be noted that modeled microlensing
optical depths diverge in the low Galactic latitude, |b| < 2 arcdeg. Therefore,
we suggest the microlensing observation toward much closer to central regions
of the Galaxy to further test the proposed Galactic models, if it is more
technically feasible than waiting for large data set of microlensing events.


title:
Tau sleptons and Tau sneutrino Decays in MSSM under the Cosmological
  Bounds

abstract:
  We present the numerical investigation of the fermionic two-body decays of
tau sleptons $\tilde \tau_{1,2}$ and $\tau$ sneutrino in the Minimal
Supersymmetric Standard Model with complex parameters. In the analysis we
particularly take into account the cosmological bounds imposed by WMAP data. We
plot the CP-phase dependences for each fermionic two-body channel of $\tilde
\tau_{1,2}$ and $\tau$ sneutrino and speculate about the branching ratios and
total (two-body) decay widths. We find that the phase dependences of the decay
widths of the third family sleptons are quite significant which can provide
viable probes of additional CP sources. We also draw attention to the
polarization of the final-state tau in the $ \tilde \tau_{1,2}$ decays.


title:
Study of the internal mechanisms of Pixelized Photon Detectors operated
  in Geiger-mode

abstract:
  In the 1990s, a novel semiconductor photon-sensor operated in Geiger-mode was
invented in Russia (Silicon PhotoMultiplier), which consists of many tiny
pixels and has a single photon level sensitivity. Since then, various types of
the sensor with this scheme, Pixelized Photon Detectors (PPD), have been
developed in many places in the world. For instance, Hamamatsu Photonics K.K.
in Japan produces the PPD as a Multi-Pixel Photon Counter. While the internal
mechanisms of the PPD have been intensively studied in recent years, the
existing models do not succeeded to fully reproduce the output characteristic,
such as waveforms at low temperature. We have developed a new model with the
transient multiplication and quenching of the realistic avalanche process and
have succeeded in reproducing the output waveform of the PPD at various
temperature. In this paper, we discuss our improved model.


title: The Variable Stars of the Draco Dwarf Spheroidal Galaxy - Revisited

abstract:
  We present a CCD survey of variable stars in the Draco dwarf spheroidal
galaxy. This survey, which has the largest areal coverage since the original
variable star survey by Baade & Swope, includes photometry for 270 RR Lyrae
stars, 9 anomalous Cepheids, 2 eclipsing binaries, and 12 slow, irregular red
variables, as well as 30 background QSOs. Twenty-six probable double-mode RR
Lyrae stars were identified. Observed parameters, including mean V and I
magnitudes, V amplitudes, and periods, have been derived. Photometric
metallicities of the ab-type RR Lyrae stars were calculated according to the
method of Jurcsik & Kovacs, yielding a mean metallicity of <[Fe/H]> = -2.19 +/-
0.03. The well known Oosterhoff intermediate nature of the RR Lyrae stars in
Draco is reconfirmed, although the double-mode RR Lyrae stars with one
exception have properties similar to those found in Oosterhoff type II globular
clusters. The period-luminosity relation of the anomalous Cepheids is
rediscussed with the addition of the new Draco anomalous Cepheids.


title: A Refined Difference Field Theory for Symbolic Summation

abstract:
  In this article we present a refined summation theory based on Karr's
difference field approach. The resulting algorithms find sum representations
with optimal nested depth. For instance, the algorithms have been applied
successively to evaluate Feynman integrals from Perturbative Quantum Field
Theory.


title:
Morphic and Automatic Words: Maximal Blocks and Diophantine
  Approximation

abstract:
  Let $\mb w$ be a morphic word over a finite alphabet $\Sigma$, and let
$\Delta$ be a nonempty subset of $\Sigma$. We study the behavior of maximal
blocks consisting only of letters from $\Delta$ in $\mb w$, and prove the
following: let $(i_k,j_k)$ denote the starting and ending positions,
respectively, of the $k$'th maximal $\Delta$-block in $\mb w$. Then
$\limsup_{k\to\infty} (j_k/i_k)$ is algebraic if $\mb w$ is morphic, and
rational if $\mb w$ is automatic. As a result, we show that the same conclusion
holds if $(i_k,j_k)$ are the starting and ending positions of the $k$'th
maximal zero block, and, more generally, of the $k$'th maximal $x$-block, where
$x$ is an arbitrary word. This enables us to draw conclusions about the
irrationality exponent of automatic and morphic numbers. In particular, we show
that the irrationality exponent of automatic (resp., morphic) numbers belonging
to a certain class that we define is rational (resp., algebraic).


title: Vector partition functions and index of transversally elliptic operators

abstract:
  Let G be a torus acting linearly on a complex vector space M, and let X be
the list of weights of G in M. We determine the equivariant K-theory of the
open subset of M consisting of points with finite stabilizers. We identify it
to the space DM(X) of functions on the lattice of weights of G, satisfying the
cocircuit difference equations associated to X, introduced by Dahmen--Micchelli
in the context of the theory of splines in order to study vector partition
functions. This allows us to determine the range of the index map from
G-transversally elliptic operators on M to generalized functions on G and to
prove that the index map is an isomorphism on the image. This is a setting
studied by Atiyah-Singer which is in a sense universal for index computations.


title: On the basic mechanism of Pixelized Photon Detectors

abstract:
  A Pixelized Photon Detector (PPD) is a generic name for the semiconductor
devices operated in the Geiger-mode, such as Silicon PhotoMultiplier and
Multi-Pixel Photon Counter, which has high photon counting capability. While
the internal mechanisms of the PPD have been intensively studied in recent
years, the existing models do not include the avalanche process. We have
simulated the multiplication and quenching of the avalanche process and have
succeeded in reproducing the output waveform of the PPD. Furthermore our model
predicts the existence of dead-time in the PPD which has never been numerically
predicted. For serching the dead-time, we also have developed waveform analysis
method using deconvolution which has the potential to distinguish neibouring
pulses precisely. In this paper, we discuss our improved model and waveform
analysis method.


title:
Weyl-Titchmarsh functions of vector-valued Sturm-Liouville operators on
  the unit interval

abstract:
  The matrix-valued Weyl-Titchmarsh functions $M(\lambda)$ of vector-valued
Sturm-Liouville operators on the unit interval with the Dirichlet boundary
conditions are considered. The collection of the eigenvalues (i.e., poles of
$M(\lambda)$) and the residues of $M(\lambda)$ is called the spectral data of
the operator. The complete characterization of spectral data (or, equivalently,
$N\times N$ Weyl-Titchmarsh functions) corresponding to $N\times N$
self-adjoint square-integrable matrix-valued potentials is given, if all $N$
eigenvalues of the averaged potential are distinct.


title: Negative Beta Encoder

abstract:
  A new class of analog-to-digital (A/D) and digital-to-analog (D/A) converters
using a flaky quantiser, called the $\beta$-encoder, has been shown to have
exponential bit rate accuracy while possessing a self-correction property for
fluctuations of the amplifier factor $\beta$ and the quantiser threshold $\nu$.
The probabilistic behavior of such a flaky quantiser is explained as the
deterministic dynamics of the multi-valued R\'enyi map. That is, a sample $x$
is always confined to a contracted subinterval while successive approximations
of $x$ are performed using $\beta$-expansion even if $\nu$ may vary at each
iteration. This viewpoint enables us to get the decoded sample, which is equal
to the midpoint of the subinterval, and its associated characteristic equation
for recovering $\beta$ which improves the quantisation error by more than
$3{dB}$ when $\beta>1.5$. The invariant subinterval under the R\'enyi map shows
that $\nu$ should be set to around the midpoint of its associated greedy and
lazy values. %in terms of its quantisation MSE (mean square error).
Furthermore, a new A/D converter is introduced called the negative
$\beta$-encoder, which further improves the quantisation error of the
$\beta$-encoder. A two-state Markov chain describing the $\beta$-encoder
suggests that a negative eigenvalue of its associated transition probability
matrix reduces the quantisation error.


title:
The swap operation in the two-qubit Heisenberg XXZ model-effects of
  anisotropy and magnetic field

abstract:
  In this paper we study the swap operation in a two-qubit anisotropic XXZ
model in the presence of an inhomogeneous magnetic field. We establish the
range of anisotropic parameter within which the swap operation is feasible. The
swap errors caused by the inhomogeneous field are evaluated.


title: The Vertical Structure of Warm Ionised Gas in the Milky Way

abstract:
  We present a new joint analysis of pulsar dispersion measures and diffuse
H-alpha emission in the Milky Way, which we use to derive the density, pressure
and filling factor of the thick disk component of the warm ionised medium (WIM)
as a function of height above the Galactic disk. By excluding sightlines at low
Galactic latitude that are contaminated by HII regions and spiral arms, we find
that the exponential scale-height of free electrons in the diffuse WIM is 1830
(+120, -250) pc, a factor of two larger than has been derived in previous
studies. The corresponding inconsistent scale heights for dispersion measure
and emission measure imply that the vertical profiles of mass and pressure in
the WIM are decoupled, and that the filling factor of WIM clouds is a geometric
response to the competing environmental influences of thermal and non-thermal
processes. Extrapolating the properties of the thick-disk WIM to mid-plane, we
infer a volume-averaged electron density 0.014 +- 0.001 cm^-3, produced by
clouds of typical electron density 0.34 +- 0.06 cm^-3 with a volume filling
factor 0.04 +- 0.01. As one moves off the plane, the filling factor increases
to a maximum of ~30% at a height of approximately 1-1.5 kpc, before then
declining to accommodate the increasing presence of hot, coronal gas. Since
models for the WIM with a ~1 kpc scale-height have been widely used to estimate
distances to radio pulsars, our revised parameters suggest that the distances
to many high-latitude pulsars have been substantially underestimated.


title: Evolution of Metric Perturbations in Quintom Bounce model

abstract:
  We in the paper study the metric perturbations generated in a bouncing
universe driven by the Quintom matter. Firstly, we review the background
evolution of Quintom Bounce and the power spectrum of scalar perturbations.
Secondly, we study the non-Gaussianity of curvature perturbations and then
calculate the tensor perturbations of the model.


title: BAT - The Bayesian Analysis Toolkit

abstract:
  We describe the development of a new toolkit for data analysis. The analysis
package is based on Bayes' Theorem, and is realized with the use of Markov
Chain Monte Carlo. This gives access to the full posterior probability
distribution. Parameter estimation, limit setting and uncertainty propagation
are implemented in a straightforward manner. A goodness-of-fit criterion is
presented which is intuitive and of great practical use.


title:
A bicategorical version of Masuoka's theorem. Applications to bimodules
  over functor categories and to firm bimodules

abstract:
  We give a bicategorical version of the main result of A. Masuoka ({Corings
and invertible bimodules,} {\em Tsukuba J. Math.} \textbf{13} (1989), 353--362)
which proposes a non-commutative version of the fact that for a faithfully flat
extension of commutative rings $R \subseteq S$, the relative Picard group
$Pic(S/R)$ is isomorphic to the Amitsur 1--cohomology group $H^1(S/R,U)$ with
coefficients in the units functor $U$.


title: The eSMA: description and first results

abstract:
  The eSMA ("extended SMA") combines the SMA, JCMT and CSO into a single
facility, providing enhanced sensitivity and spatial resolution owing to the
increased collecting area at the longest baselines. Until ALMA early science
observing (2011), the eSMA will be the facility capable of the highest angular
resolution observations at 345 GHz. The gain in sensitivity and resolution will
bring new insights in a variety of fields, such as protoplanetary/transition
disks, high-mass star formation, solar system bodies, nearby and high-z
galaxies. Therefore the eSMA is an important facility to prepare the grounds
for ALMA and train scientists in the techniques.
  Over the last two years, and especially since November 2006, there has been
substantial progress toward making the eSMA into a working interferometer. In
particular, (i) new 345-GHz receivers, that match the capabilities of the SMA
system, were installed at the JCMT and CSO; (ii) numerous tests have been
performed for receiver, correlator and baseline calibrations in order to
determine and take into account the effects arising from the differences
between the three types of antennas; (iii) first fringes at 345 GHz were
obtained on August 30 2007, and the array has entered the science-verification
stage.
  We report on the characteristics of the eSMA and its measured performance at
230 GHz and that expected at 345 GHz. We also present the results of the
commissioning and some initial science-verification observations, including the
first absorption measurement of the C/CO ratio in a galaxy at z=0.89, located
along the line of sight to the lensed quasar PKS1830-211, and on the imaging of
the vibrationally excited HCN line towards IRC+10216.


title: Semi-numerical power expansion of Feynman integrals

abstract:
  I present an algorithm based on sector decomposition and Mellin-Barnes
techniques to power expand Feynman integrals. The coefficients of this
expansion are given in terms of finite integrals that can be calculated
numerically. I show in an example the benefit of this method for getting the
full analytic power expansion from differential equations by providing the
correct ansatz for the solution. For method of regions the presented algorithm
provides a numerical check, which is independent from any power counting
argument.


title: Galois sections for abelianized fundamental groups

abstract:
  Given a smooth projective curve $X$ of genus at least 2 over a number field
$k$, Grothendieck's Section Conjecture predicts that the canonical projection
from the \'etale fundamental group of $X$ onto the absolute Galois group of $k$
has a section if and only if the curve has a rational point. We show that there
exist curves where the above map has a section over each completion of $k$ but
not over $k$. In the appendix Victor Flynn gives explicit examples in genus 2.
  Our result is a consequence of a more general investigation of the existence
of sections for the projection of the \'etale fundamental group `with
abelianized geometric part' onto the Galois group. We give a criterion for the
existence of sections in arbitrary dimension and over arbitrary perfect fields,
and then study the case of curves over local and global fields more closely. We
also point out the relation to the elementary obstruction of
Colliot-Th\'el\`ene and Sansuc.


title: Quantum Many-Body Phenomena in Coupled Cavity Arrays

abstract:
  The increasing level of experimental control over atomic and optical systems
gained in the past years have paved the way for the exploration of new physical
regimes in quantum optics and atomic physics, characterised by the appearance
of quantum many-body phenomena, originally encountered only in condensed-matter
physics, and the possibility of experimentally accessing them in a more
controlled manner. In this review article we survey recent theoretical studies
concerning the use of cavity quantum electrodynamics to create quantum
many-body systems. Based on recent experimental progress in the fabrication of
arrays of interacting micro-cavities and on their coupling to atomic-like
structures in several different physical architectures, we review proposals on
the realisation of paradigmatic many-body models in such systems, such as the
Bose-Hubbard and the anisotropic Heisenberg models. Such arrays of coupled
cavities offer interesting properties as simulators of quantum many-body
physics, including the full addressability of individual sites and the
accessibility of inhomogeneous models.


title:
A catalog of variable stars in the Kepler field of view found in the
  ASAS3-North data

abstract:
  We announce the release of the catalog of variable stars in the field of view
of Kepler mission found from the analysis of the ASAS3-North VI photometry of
about 250,000 stars.


title:
Density of States for a Short Overlapping-Bead Polymer: Clues to a
  Mechanism for Helix Formation?

abstract:
  The densities of states are evaluated for very short chain molecules made up
of overlapping monomers, using a model which has previously been shown to
produce helical structure. The results of numerical calculations are presented
for tetramers and pentamers. We show that these models demonstrate behaviors
relevant to the behaviors seen in longer, helix forming chains, particularly,
"magic numbers" of the overlap parameter where the derivatives of the densities
of states change discontinuously, and a region of bimodal energy probability
distributions, reminiscent of a first order phase transition in a bulk system.


title:
Mean-field approach to nuclear structure with semi-realistic
  nucleon-nucleon interactions

abstract:
  Semi-realistic nucleon-nucleon interactions applicable to the self-consistent
mean-field (both Hartree-Fock and Hartree-Fock-Bogolyubov) calculations are
developed, by modifying the M3Y interaction. The modification is made so as to
reproduce binding energies and rms matter radii of doubly magic nuclei,
single-particle levels in $^{208}$Pb, and even-odd mass differences of the Sn
isotopes. We find parameter-sets with and without the tensor force. The new
interactions are further checked by the saturation properties of the uniform
nuclear matter including the Landau-Migdal parameters. By the mean-field
calculations, interaction-dependence of the neutron drip line is investigated
for the O, Ca and Ni isotopes, and of the single-particle energies for the
N=16, 32, 50, 82 and Z=50 nuclei. Results of the semi-realistic interactions
including the tensor force are in fair agreement with available experimental
data for all of these properties.


title: Quantum Einstein-Rosen waves: Coherent states and n-point functions

abstract:
  We discuss two different types of issues concerning the quantization of
Einstein-Rosen waves. First of all we study in detail the possibility of using
the coherent states corresponding to the dynamics of the auxiliary, free
Hamiltonian appearing in the description of the model to study the full
dynamics of the system. For time periods of arbitrary length we show that this
is only possible for states that are close, in a precise mathematical sense, to
the vacuum. We do this by comparing the quantum evolutions defined by the
auxiliary and physical Hamiltonians on the class of coherent states. In the
second part of the paper we study the structure of n-point functions. As we
will show their detailed behavior differs from the one corresponding to
standard perturbative quantum field theories. We take this as a manifestation
of the fact that the correct approximation scheme for physically interesting
objects in these models does not lead to a power series expansion in the
relevant coupling constant but to a more complicated asymptotic behavior.


title:
Spectrum Sensing Algorithms for Cognitive Radio Based on Statistical
  Covariances

abstract:
  Spectrum sensing, i.e., detecting the presence of primary users in a licensed
spectrum, is a fundamental problem in cognitive radio. Since the statistical
covariances of received signal and noise are usually different, they can be
used to differentiate the case where the primary user's signal is present from
the case where there is only noise. In this paper, spectrum sensing algorithms
are proposed based on the sample covariance matrix calculated from a limited
number of received signal samples. Two test statistics are then extracted from
the sample covariance matrix. A decision on the signal presence is made by
comparing the two test statistics. Theoretical analysis for the proposed
algorithms is given. Detection probability and associated threshold are found
based on statistical theory. The methods do not need any information of the
signal, the channel and noise power a priori. Also, no synchronization is
needed. Simulations based on narrowband signals, captured digital television
(DTV) signals and multiple antenna signals are presented to verify the methods.


title: Quantum scaling in nano-transistors

abstract:
  In our previous papers on ballistic quantum transport in nano-transistors [J.
Appl. Phys. 98, 84308 (2005)] it was demonstrated that under certain conditions
it is possible to reduce the three-dimensional transport problem to an
effectively one-dimensional one. We show that such an effectively
one-dimensional description can be cast in a scale-invariant form. We obtain
dimensionless variables for the characteristic channel length $l$ and width of
the transistor which determine the scale-invariant output characteristic. For
$l \gtrsim 10$, in the strong barrier regime, the output characteristics are
similar to that of a conventional MOSFET assuming an ideal form for $l \to
\infty$. In the weak barrier regime, $l \lesssim 10$, strong source-drain
currents lead to i-v characteristics that differ qualitatively from that of a
conventional transistor. Comparing with experimental data we find qualitative
agreement.


title: Pionic transparency in semi-exclusive electroproduction off nuclei

abstract:
  We investigate the early onset of pionic color transparency ($\pi$CT)
observed at Jefferson Laboratory (JLAB) in semi--exclusive pion
electroproduction reaction $A(e,e'\pi^+)$ off nuclei. In the present
description the primary $\gamma^*p \to \pi^+ n$ interaction is described very
well both for the longitudinal and the transverse polarizations. For the final
state interactions a coupled--channel treatment of the interactions of
transmitted hadrons allows to go beyond the Glauber approximation. We show that
a proper distinction between the soft hadronic and hard partonic components of
the electroproduction amplitude is essential for a quantitative description of
the measured nuclear transparency. The data are well reproduced if one assumes
that point--like configurations are produced in the regime of hard
deep--inelastic scattering (DIS) off partons and dominate the transverse
channel.


title:
Localized states and interaction induced delocalization in Bose gases
  with quenched disorder

abstract:
  Very diluted Bose gas placed into a disordered environment falls into a
fragmented localized state. At some critical density the repulsion between
particles overcomes the disorder. The gas transits into a coherent superfluid
state. In this article the geometrical and energetic characteristics of the
localized state at zero temperature and the critical density at which the
quantum phase transition from the localized to the superfluid state proceeds
are found.


title: Magnetic properties of PrCu$_2$ at high pressure

abstract:
  We report a study of the low-temperature high-pressure phase diagram of the
intermetallic compound PrCu$_2$, by means of molecular-field calculations and
$^{63,65}$Cu nuclear-quadrupole-resonance (NQR) measurements under pressure.
The pressure-induced magnetically-ordered phase can be accounted for by
considering the influence of the crystal electric field on the $4f$ electron
orbitals of the Pr$^{3+}$ ions and by introducing a pressure-dependent exchange
interaction between the corresponding local magnetic moments. Our experimental
data suggest that the order in the induced antiferromagnetic phase is
incommensurate. The role of magnetic fluctuations both at high and low
pressures is also discussed.


title: The Flavour of Inflation

abstract:
  A new class of particle physics models of inflation based on the phase
transition associated with the spontaneous breaking of family symmetry is
proposed. The Higgs fields responsible for the breaking of family symmetry, the
flavons, are natural inflaton candidates or waterfall fields in hybrid
inflation. This opens up a rich vein of possible inflation models, all linked
to the physics of flavour, with several interesting cosmological implications.


title: Study of Systematic Uncertainties of Single Top Production at ATLAS

abstract:
  Sytematic uncertainties to the single top production cross section
measurement at the ATLAS experiment has been studied. Different sources of
systematic uncertainties such as detector luminosity, jet energy calibration,
SM background normalization, PDF parameterization and others have been
considered. Large scale Monte-Carlo events simulation has been performed to
estimate the contribution of each source in the overall uncertainty. The study
was done for cut based analysis as well as for multivariate analysis of the
single top measurements in ATLAS. The total systematic uncertainties of the
single top cross-section measurements in its three production channels have
been estimated at 1 $\mathrm{fb}^{-1}$ and 10 $\mathrm{fb}^{-1}$ integrated
luminosity of the LHC.


title:
Correlation Energy and the Spin Susceptibility of the Two-Valley
  Two-dimensional Electron Gas

abstract:
  We find that the spin susceptibility of a two-dimensional electron system
with valley degeneracy does not grow critically at low densities, at variance
with experimental results [A. Shashkin et al., Phys. Rev. Lett. 96, 036403
(2006)]. We ascribe this apparent discrepancy to the weak disorder present in
experimental samples. Our prediction is obtained from accurate correlation
energies computed with state of-the-art diffusion Monte Carlo simulations and
fitted with an analytical expression which also provides a local spin density
functional for the system under investigation.


title: Effects of a localized beam on the dynamics of excitable cavity solitons

abstract:
  We study the dynamical behavior of dissipative solitons in an optical cavity
filled with a Kerr medium when a localized beam is applied on top of the
homogeneous pumping. In particular, we report on the excitability regime that
cavity solitons exhibits which is emergent property since the system is not
locally excitable. The resulting scenario differs in an important way from the
case of a purely homogeneous pump and now two different excitable regimes, both
Class I, are shown. The whole scenario is presented and discussed, showing that
it is organized by three codimension-2 points. Moreover, the localized beam can
be used to control important features, such as the excitable threshold,
improving the possibilities for the experimental observation of this
phenomenon.


title:
On the First Order Phase Transitions Signal in Multiple Production
  Processes

abstract:
  We offer the parameter, interpreted as the "chemical potential", which is
sensitive to the first order phase transition: it must decrease with number of
evaporating (produced) particles (hadrons) if the (interacting hadron or/and
QCD plasma) medium is boiling and it increase if no phase transition occur. The
main part of the paper is devoted to the question: how one can measure the
"chemical potential" in the hadron inelastic processes. Our definition of this
parameter is quite general but assumes that the hadron multiplicity is
sufficiently large. The simple transparent phenomenological lattice gas model
is considered for sake of clarity only.


title: Axions and Photons In Terms of "Particles" and "Anti-Particles"

abstract:
  The axion photon system in an external magnetic field, when for example
considered with the geometry of the experiments exploring axion photon mixing
(which can be represented by a 1+1 effective model) displays a continuous
axion-photon duality symmetry in the limit the axion mass is neglected. The
conservation law that follows from this symmetry is obtained. The magnetic
field interaction is seen to be equivalent to first order to the interaction of
a complex charged field with an external electric potential, where this
ficticious "electric potential" is proportional to the external magnetic field.
This allows one to solve for the scattering amplitudes using already known
scalar QED results. Axion photon oscillations can be understood as violations
of a charge symmetry in the scalar QED language. Going beyond the linear
theory, the axion photon system in a self consistent magnetic field is shown,
using this formalism, to have interesting soliton solutions that represent new
non gravitational ways of trapping light. Finally, generalizing the scalar QED
formalism to 2+1 dimensions makes it clear that a photon and an axion splitt
into two components in an inhomogeneous magnetic field, an effect that reminds
us of the Stern Gerlach experiment.


title:
A method for characterization of coherent backgrounds in real time and
  its application in gravitational wave data analysis

abstract:
  Many experiments, and in particular gravitational wave detectors, produce
continuous streams of data whose frequency representations contain discrete,
relatively narrowband coherent features at high amplitude. We discuss the
application of digital Fourier transforms (DFTs) to characterization of these
features, hereafter frequently referred to as lines. Application of DFTs to
continuously produced time domain data are achieved through an algorithm
hereafter referred to as EFC for efficient time-domain determination of the
Fourier coefficients of a data set. We first define EFC and discuss parameters
relating to the algorithm that determine its properties and action on the data.
In gravitational wave interferometers, these lines are commonly due to
parasitic sources of coherent background interference coupling into the
instrument. Using GEO 600 data, we next demonstrate that time domain
subtraction of lines can proceed without detrimental effects either on features
at frequencies separated from that of the subtracted line, or on features at
the frequency of the line but having different stationarity properties.


title: A Better Way to Reconstruct Dark Energy Models ?

abstract:
  To reconstruct dark energy models the redshift $z_{eq}$, marking the end of
radiation era and the beginning of matter-dominated era, can play a role as
important as $z_{t}$, the redshift at which deceleration parameter experiences
a signature flip. To implement the idea we propose a variable equation of state
for matter that can bring a smooth transition from radiation to
matter-dominated era in a single model. A popular $\Lambda \propto \rho$ dark
energy model is chosen for demonstration but found to be unacceptable. An
alternative $\Lambda \propto \rho a^{3}$ model is proposed and found to be more
close to observation.


title:
Consistent boundary conditions for cosmological topologically massive
  gravity at the chiral point

abstract:
  We show that cosmological topologically massive gravity at the chiral point
allows not only Brown-Henneaux boundary conditions as consistent boundary
conditions, but slightly more general ones which encompass the logarithmic
primary found in 0805.2610 as well as all its descendants.


title:
Measurement of $B^0\to\pi^+\pi^-\pi^+\pi^-$ Decays and Search for
  $B^0\to\rho^0\rho^0$

abstract:
  We report on a search for the decay $B^0\to\rho^0\rho^0$ and other charmless
modes with a $\pi^+\pi^-\pi^+\pi^-$ final state, including
$B^0\to\rho^0\pi^+\pi^-$, non-resonant $B^0\to 4\pi^{\pm}$,
$B^0\to\rho^0f_0(980)$, $B^0\to f_0(980)f_0(980)$ and $B^0\to
f_0(980)\pi^+\pi^-$. These results are obtained from a data sample containing
657 million $B \overline B$ pairs collected with the Belle detector at the KEKB
asymmetric-energy $e^+e^-$ collider. We set an upper limit on
$\mathcal{B}(B^0\to\rho^0\rho^0)$ of $1.0\times 10^{-6}$ at the 90% confidence
level (C.L.). From our $B^0\to\rho^0\rho^0$ measurement and an isospin
analysis, we determine the Cabibbo-Kobayashi-Maskawa phase $\phi_2$ to be $91.7
\pm 14.9$ degrees. We find excesses in $B^0\to \rho^0\pi^+\pi^-$ and
non-resonant $B^0\to 4\pi^{\pm}$ with 1.3$\sigma$ and 2.5$\sigma$ significance,
respectively. The corresponding branching fractions are less than $12.0 \times
10^{-6}$ and $19.3 \times 10^{-6}$ at the 90% C.L. In addition, we set 90% C.L.
upper limits as follows: $\mathcal{B}(B^0\to\rho^0f_0(980))< 0.3 \times
10^{-6}$, $\mathcal{B}(B^0\to f_0(980)f_0(980))< 0.1 \times 10^{-6}$, and
$\mathcal{B}(B^0\to f_0(980)\pi^+\pi^-)< 3.8 \times 10^{-6}$.


title: A random telegraph signal of Mittag-Leffler type

abstract:
  A general method is presented to explicitly compute autocovariance functions
for non-Poisson dichotomous noise based on renewal theory. The method is
specialized to a random telegraph signal of Mittag-Leffler type. Analytical
predictions are compared to Monte Carlo simulations. Non-Poisson dichotomous
noise is non-stationary and standard spectral methods fail to describe it
properly as they assume stationarity.


title: Equivalence of robust stabilization and robust performance via feedback

abstract:
  One approach to robust control for linear plants with structured uncertainty
as well as for linear parameter-varying (LPV) plants (where the controller has
on-line access to the varying plant parameters) is through
linear-fractional-transformation (LFT) models. Control issues to be addressed
by controller design in this formalism include robust stability and robust
performance. Here robust performance is defined as the achievement of a uniform
specified $L^{2}$-gain tolerance for a disturbance-to-error map combined with
robust stability. By setting the disturbance and error channels equal to zero,
it is clear that any criterion for robust performance also produces a criterion
for robust stability. Counter-intuitively, as a consequence of the so-called
Main Loop Theorem, application of a result on robust stability to a feedback
configuration with an artificial full-block uncertainty operator added in
feedback connection between the error and disturbance signals produces a result
on robust performance. The main result here is that this
performance-to-stabilization reduction principle must be handled with care for
the case of dynamic feedback compensation: casual application of this principle
leads to the solution of a physically uninteresting problem, where the
controller is assumed to have access to the states in the artificially-added
feedback loop. Application of the principle using a known more refined
dynamic-control robust stability criterion, where the user is allowed to
specify controller partial-state dimensions, leads to correct
robust-performance results. These latter results involve rank conditions in
addition to Linear Matrix Inequality (LMI) conditions.


title: Parton Densities at the LHC

abstract:
  This contribution to the Italian "Workshop sui Monte Carlo, la Fisica e le
Simulazioni a LHC", held at LNF, Frascati, in February, May and October 2006,
summarises the status of parton density functions (PDF's) and the impact of
their uncertainties on the LHC physics. Emphasis is given to methods of
contraining PDF's using LHC data. Moreover, the advantages of the so-called PDF
reweighting technique, which enables to quickly estimate PDF uncertainties with
Monte Carlo events, are also presented.


title:
Low-energy magnetic response of the noncentrosymmetric heavy-fermion
  superconductor CePt3Si studied via inelastic neutron scattering

abstract:
  The low-energy magnetic excitations of the noncentrosymmetric heavy-fermion
superconductor CePt3Si have been measured with inelastic neutron scattering on
a single crystal. Kondo-type spin fluctuations with an anisotropic wave vector
dependence are observed in the paramagnetic state. These fluctuations do not
survive in the antiferromagnetically ordered state below TN=2.2 K but are
replaced by damped spin waves, whose dispersion is much stronger along the
c-axis than in other directions. No change is observed in the excitation
spectrum or the magnetic order as the system enters the superconducting state
below Tc=0.7 K.


title:
Separability bounds on multiqubit moments due to positivity under
  partial transpose

abstract:
  Positivity of the density operator reflects itself in terms of sequences of
inequalities on observable moments. Uncertainty relations for non-commuting
observables form a subset of these inequalities. In addition, criterion of
positivity under partial transposition (PPT) imposes distinct bounds on
moments, violations of which signal entanglement. We present bounds on some
novel sets of composite moments, consequent to positive partial transposition
of the density operator and report their violation by entangled multiqubit
states. In particular, we derive separability bounds on a multiqubit moment
matrix (based on PPT constraints on bipartite divisions of the density matrix)
and show that three qubit pure states with non-zero tangle violate these PPT
moment constraints. Further, we recover necessary and sufficient condition of
separability in a multiqubit Werner state through PPT bounds on moments.


title: Muon Charge Ratio of Ultrahigh Energy Cosmic Rays

abstract:
  The muon charge ratio of ultrahigh energy cosmic rays may provide information
to detect the composition of the primary cosmic rays. We propose to extract the
charge information of high energy muons in very inclined extensive air showers
by analyzing their relative lateral positions in the shower transverse plane.


title:
Colloidal electrophoresis: Scaling analysis, Green-Kubo relation, and
  numerical results

abstract:
  We consider electrophoresis of a single charged colloidal particle in a
finite box with periodic boundary conditions, where added counterions and salt
ions ensure charge neutrality. A systematic rescaling of the electrokinetic
equations allows us to identify a minimum set of suitable dimensionless
parameters, which, within this theoretical framework, determine the reduced
electrophoretic mobility. It turns out that the salt-free case can, on the Mean
Field level, be described in terms of just three parameters. A fourth
parameter, which had previously been identified on the basis of straightforward
dimensional analysis, can only be important beyond Mean Field. More complicated
behavior is expected to arise when further ionic species are added. However,
for a certain parameter regime, we can demonstrate that the salt-free case can
be mapped onto a corresponding system containing additional salt. The
Green-Kubo formula for the electrophoretic mobility is derived, and its
usefulness demonstrated by simulation data. Finally, we report on
finite-element solutions of the electrokinetic equations, using the commercial
software package COMSOL.


title: On Transformations of Load-Store Maurer Instruction Set Architecture

abstract:
  In this paper, we study how certain conditions can affect the transformations
on the states of the memory of a strict load-store Maurer ISA, when half of the
data memory serves as the part of the operating unit.


title: Star cluster evolution in the Magellanic Clouds revisited

abstract:
  The evolution of star clusters in the Magellanic Clouds has been the subject
of significant recent controversy, particularly regarding the importance and
length of the earliest, largely mass-independent disruption phase (referred to
as "infant mortality"). Here, we take a fresh approach to the problem, using a
large, independent, and homogeneous data set of UBVR imaging observations, from
which we obtain the cluster age and mass distributions in both the Large and
Small Magelanic Clouds (LMC, SMC) in a self-consistent manner. We conclude that
the (optically selected) SMC star cluster population has undergone at most ~30%
(1sigma) infant mortality between the age range from about 3-10 Myr, to that of
approximately 40-160 Myr. We rule out a 90% cluster mortality rate per decade
of age (for the full age range up to 10^9 yr) at a >6sigma level. Using a
simple approach, we derive a "characteristic" cluster disruption time-scale for
the cluster population in the LMC that implies that we are observing the
INITIAL cluster mass function. Preliminary results suggest that the LMC cluster
population may be affected by <10% infant mortality.


title: Towards Provable Secure Neighbor Discovery in Wireless Networks

abstract:
  In wireless systems, neighbor discovery (ND) is a fundamental building block:
determining which devices are within direct radio communication is an enabler
for networking protocols and a wide range of applications. To thwart abuse of
ND and the resultant compromise of the dependent functionality of wireless
systems, numerous works proposed solutions to secure ND. Nonetheless, until
very recently, there has been no formal analysis of secure ND protocols. We
close this gap in \cite{asiaccs08}, but we concentrate primarily on the
derivation of an impossibility result for a class of protocols. In this paper,
we focus on reasoning about specific protocols. First, we contribute a number
of extensions and refinements on the framework of [24]. As we are particularly
concerned with the practicality of provably secure ND protocols, we investigate
availability and redefine accordingly the ND specification, and also consider
composability of ND with other protocols. Then, we propose and analyze two
secure ND protocols: We revisit one of the protocols analyzed in [24], and
introduce and prove correct a more elaborate challenge-response protocol.


title: Charm Physics - A Field Full with Challenges and Opportunities

abstract:
  In this review, we discuss some interesting issues in charm physics which is
full with puzzles and challenges. So far in the field there exist many problems
which have not obtained satisfactory answers yet and more unexpected phenomena
have been observed at the present facilities of high energy physics. Charm
physics may become an ideal place for searching new resonances and studying
non-perturbative QCD effects, moreover probably is an area to explore new
physics beyond the Standard Model. More data will be available at BESIII,
B-factories, LHC and even future ILC which may open a wide window to a better
understanding of the nature.


title: Stickelberger elements and Kolyvagin systems

abstract:
  In this paper, we construct (many) Kolyvagin systems out of Stickelberger
elements, utilizing ideas borrowed from our previous work on Kolyvagin systems
of Rubin-Stark elements. We show how to apply this construction to prove
results on the odd parts of the ideal class groups of CM fields which are
abelian over a totally real field, and deduce the main conjecture of Iwasawa
theory for totally real fields (for totally odd characters). Although the main
results of this paper have already been established by Wiles, our approach
provides another example (which slightly differs from the case of Stark
elements) on how to study Kolyvagin systems of core rank r > 1 (in the sense of
Mazur and Rubin). Also, by making use of the 'rigidity' of the collection of
Kolyvagin systems, we establish a link between the Stickelberger elements and
the Rubin-Stark elements.


title:
Tracking heterogeneous dynamics during the alpha-relaxation of a simple
  glass-former

abstract:
  We study the relaxation process in a simple glass-former - the KA lattice gas
model. We show that, for this model, structural relaxation is due to slow
percolation of regions of co-operatively moving particles, which leads to
heterogeneous dynamics of the system. We find that the size distribution of
these regions is given by a power-law and that their formation is encoded in
the initial structure of the particles, with the memory of initial
configuration increasingly retained with increasing density.


title: Measuring the Charged Particle Multiplicity with ALICE

abstract:
  The charged particle multiplicity distribution is one of the first
measurements that ALICE will be able to perform. The knowledge of this basic
property at a new energy is needed to configure Monte Carlo generators
correctly with the aim of understanding the background of other, especially
rare, processes including new physics. It allows to study the scaling behaviour
and to verify model predictions. The unfolding of the measurement is a
non-trivial task due to the finite precision and acceptance of the detector.
Solutions are based on chi2 minimization or iteratively using Bayes' theorem.
Both approaches to unfold the spectrum are presented. Furthermore, the
capabilities of the SPD fast OR trigger are shown that enable physics at very
high multiplicities.