title:
Gate-dependent tunneling-induced level shifts observed in carbon
  nanotube quantum dots

abstract:
  We have studied electron transport in clean single-walled carbon nanotube
quantum dots. Because of the large number of Coulomb blockade diamonds
simultaneously showing both shell structure and Kondo effect, we are able to
perform a detailed analysis of tunneling renormalization effects. Thus
determining the environment induced level shifts of this artificial atom. In
shells where only one of the two orbitals is coupled strongly, we observe a
marked asymmetric gate-dependence of the inelastic cotunneling lines together
with a systematic gate dependence of the size (and shape) of the Coulomb
diamonds. These effects are all given a simple explanation in terms of
second-order perturbation theory in the tunnel coupling.


title:
Use of Complex Lie Symmetries for Linearization of Systems of
  Differential Equations - I: Ordinary Differential Equations

abstract:
  The Lie linearizability criteria are extended to complex functions for
complex ordinary differential equations. The linearizability of complex
ordinary differential equations is used to study the linearizability of
corresponding systems of two real ordinary differential equations. The
transformations that map a system of two nonlinear ordinary differential
equations into systems of linear ordinary differential equations are obtained
from complex transformations. Invariant criteria for linearization are given
for second order complex ordinary differential equations in terms of the
coefficients of the equations, as well as the corresponding real system, which
provide procedures for writing down the solutions of the equations.
Illustrative examples are given and discussed.


title: Classical and quantum integrability in 3D systems

abstract:
  In this contribution, we discuss three situations in which complete
integrability of a three dimensional classical system and its quantum version
can be achieved under some conditions. The former is a system with axial
symmetry. In the second, we discuss a three dimensional system without spatial
symmetry which admits separation of variables if we use ellipsoidal
coordinates. In both cases, and as a condition for integrability, certain
conditions arise in the integrals of motion. Finally, we study integrability in
the three dimensional sphere and a particular case associated with the Kepler
problem in $S^3$.


title: Variable stars in the field of open cluster NGC 6939

abstract:
  The results of CCD photometric survey performed with the 90/180 cm
Schmidt-Cassegrain Telescope of the Nicolaus Copernicus University Astronomical
Observatory in Piwnice (Poland) and the 70/172 cm Schmidt Telescope of the
National Astronomical Observatory (NAO) at Rozhen (Bulgaria) of the field of 1
Gyr old open cluster NGC 6939 are presented. Twenty two variable stars were
detected, four of them previously known. Four eclipsing systems (3 detached and
1 contact binary) were found to be members of the cluster. Analysis of the
brightness of the contact binary V20 strongly supports the distance to the
cluster of 1.74 +/- 0.20 kpc. The small population of contact binaries in NGC
6939 confirms also the relatively young age of the cluster.


title:
Massive gravitational waves from the R^2 theory of gravity: production
  and response of interferometers

abstract:
  We show that from the R^{2} high order gravity theory it is possible to
produce, in the linearized approch, particles which can be seen like massive
modes of gravitational waves (GWs). The presence of the mass generates a
longitudinal force in addition of the transverse one which is proper of the
massless gravitational waves and the response an interferometer to the effect
is computed. This could be, in principle, important to discriminate among the
gravity theories. The presence of the mass could also have important
applications in cosmology because the fact that gravitational waves can have
mass could give a contribution to the dark matter of the Universe.


title: Microscopic heat from the energetics of stochastic phenomena

abstract:
  The energetics of the stochastic process has shown the balance of energy on
the mesoscopic level. The heat and the energy defined there are, however,
generally different from their macroscopic counterpart. We show that this
discrepancy can be removed by adding to these quantities the reversible heat
associated with the mesoscopic free energy.


title: Quantum Wire Hybridized with a Single-Level Impurity

abstract:
  We have studied low-temperature properties of interacting electrons in a
one-dimensional quantum wire (Luttinger liquid) side-hybridized with a
single-level impurity. The hybridization induces a back-scattering of electrons
in the wire which strongly affects its low energy properties. Using a one-loop
renormalization group approach valid for a weak electron-electron interaction,
we have calculated a transmission coefficient through the wire,
$\mathcal{T}(\varepsilon)$, and a local density of states, $\nu(\varepsilon)$
at low energies $\varepsilon $. In particular, we have found that the
antiresonance in $\mathcal{T}(\varepsilon)$ has a generalized Breit-Wigner
shape with the effective width $\Gamma(\varepsilon)$ which diverges at the
Fermi level.


title:
State selective differential cross sections for single and double
  electron capture in $He\sp{1,2+}-He$ and $p-He$ collisons

abstract:
  Using the COLTRIMStechnique, scattering angle differential cross sections for
single and double electron capture in collisions of protons and $He\sp{1,2+}$
projectiles with helium atoms for incident energies of $60-630 keV/u$ are
measured. We also report new theoretical results obtained by means of four-body
one-channel distorted wave models (CDW-BFS, CDW-BIS and BDW), and find mixed
agreement with the measured data.


title:
Use of Complex Lie Symmetries for Linearization of Systems of
  Differential Equations - II: Partial Differential Equations

abstract:
  The linearization of complex ordinary differential equations is studied by
extending Lie's criteria for linearizability to complex functions of complex
variables. It is shown that the linearization of complex ordinary differential
equations implies the linearizability of systems of partial differential
equations corresponding to those complex ordinary differential equations. The
invertible complex transformations can be used to obtain invertible real
transformations that map a system of nonlinear partial differential equations
into a system of linear partial differential equation. Explicit invariant
criteria are given that provide procedures for writing down the solutions of
the linearized equations. A few non-trivial examples are mentioned.


title:
Evolution of asymptotic giant branch stars II. Optical to far-infrared
  isochrones with improved TP-AGB models

abstract:
  We present a large set of theoretical isochrones, whose distinctive features
mostly reside on the greatly improved treatment of the thermally pulsing
asymptotic giant branch (TP-AGB) phase. Essentially, we have coupled the TP-AGB
tracks described in Paper I, at their stages of pre-flash quiescent H-shell
burning, with the evolutionary tracks for the previous evolutionary phases from
Girardi et al. (2000). Theoretical isochrones for any intermediate value of age
and metallicity are then derived by interpolation in the grids. We take care
that the isochrones keep, to a good level of detail, the several peculiarities
present in these TP-AGB tracks. Theoretical isochrones are then converted to
about 20 different photometric systems -- including traditional ground-based
systems, and those of recent major wide-field surveys such as SDSS, OGLE,
DENIS, 2MASS, UKIDSS, etc., -- by means of synthetic photometry applied to an
updated library of stellar spectra, suitably extended to include C-type stars.
Finally, we correct the predicted photometry by the effect of circumstellar
dust during the mass-losing stages of the AGB evolution, which allows us to
improve the results for the optical-to-infrared systems, and to simulate mid-
and far-IR systems such as those of Spitzer and AKARI. Access to the data is
provided both via a web repository of static tables
(http://stev.oapd.inaf.it/dustyAGB07 and CDS), and via an interactive web
interface (http://stev.oapd.inaf.it/cmd) that provides tables for any
intermediate value of age and metallicity, for several photometric systems, and
for different choices of dust properties.


title: A search of very low amplitude magnetoacoustic pulsations with HARPS

abstract:
  We have obtained time-resolved spectroscopic observations for a sample of 10
cool Ap stars using the ultra-stable spectrograph HARPS at the ESO 3.6-m
telescope. The aim of our study was to search for low-amplitude oscillations in
Ap stars with no or inconclusive evidence of pulsational variability. Here we
report initial results of our investigation. We confirm the presence of ~16-min
period pulsations in beta CrB (HD 137909) and demonstrate multiperiodic
character of oscillations in this star. Furthermore, we discovered very low
amplitude 9-min pulsations in HD 75445 - an object spectroscopically very
similar to known roAp stars.


title: Nonuniform Bribery

abstract:
  We study the concept of bribery in the situation where voters are willing to
change their votes as we ask them, but where their prices depend on the nature
of the change we request. Our model is an extension of the one of Faliszewski
et al. [FHH06], where each voter has a single price for any change we may ask
for. We show polynomial-time algorithms for our version of bribery for a broad
range of voting protocols, including plurality, veto, approval, and utility
based voting. In addition to our polynomial-time algorithms we provide
NP-completeness results for a couple of our nonuniform bribery problems for
weighted voters, and a couple of approximation algorithms for NP-complete
bribery problems defined in [FHH06] (in particular, an FPTAS for
plurality-weighted-$bribery problem).


title: Improved Berezin-Li-Yau inequalities with a remainder term

abstract:
  We give an improvement of sharp Berezin type bounds on the Riesz means
$\sum_k(\Lambda-\lambda_k)_+^\sigma$ of the eigenvalues $\lambda_k$ of the
Dirichlet Laplacian in a domain if $\sigma\geq 3/2$. It contains a correction
term of the order of the standard second term in the Weyl asymptotics. The
result is based on an application of sharp Lieb-Thirring inequalities with
operator valued potential to spectral estimates of the Dirichlet Laplacian in
domains.


title:
Absolute frequency measurement of the magnesium intercombination
  transition $^1S_0 \to ^3P_1$

abstract:
  We report on a frequency measurement of the $(3s^2)^1S_0\to(3s3p)^3P_1$ clock
transition of $^{24}$Mg on a thermal atomic beam. The intercombination
transition has been referenced to a portable primary Cs frequency standard with
the help of a femtosecond fiber laser frequency comb. The achieved uncertainty
is $2.5\times10^{-12}$ which corresponds to an increase in accuracy of six
orders of magnitude compared to previous results. The measured frequency value
permits the calculation of several other optical transitions from $^1S_0$ to
the $^3P_J$-level system for $^{24}$Mg, $^{25}$Mg and $^{26}$Mg. We describe in
detail the components of our optical frequency standard like the stabilized
spectroscopy laser, the atomic beam apparatus used for Ramsey-Bord\'e
interferometry and the frequency comb generator and discuss the uncertainty
contributions to our measurement including the first and second order Doppler
effect. An upper limit of $3\times10^{-13}$ in one second for the short term
instability of our optical frequency standard was determined by comparison with
a GPS disciplined quartz oscillator.


title: The double pulsar: evolutionary constraints from the system geometry

abstract:
  The double pulsar system PSR J0737-3039A/B is a highly relativistic double
neutron star (DNS) binary, with a 2.4-hour orbital period. The low mass of the
second-formed NS, as well the low system eccentricity and proper motion, point
to a different evolutionary scenario compared to other known DNS systems. We
describe analysis of the pulse profile shape over 6 years of observations, and
present the resulting constraints on the system geometry. We find the recycled
pulsar in this system, PSR J0737-3039A, to have a low misalignment between its
spin and orbital angular momentum axes, with a 68.3% upper limit of 6.1
degrees, assuming emission from both magnetic poles. This tight constraint
lends credence to the idea that the supernova that formed the second pulsar was
relatively symmetric, possibly involving electron-capture onto an O-Ne-Mg core.


title: Kaonic hydrogen versus the $K^{-}p$ low energy data

abstract:
  We present an exact solution to the $K^{-}$-proton bound state problem
formulated in the momentum space. The 1s level characteristics of the kaonic
hydrogen are computed simultaneously with the available low energy $K^{-}p$
data. In the strong interaction sector the meson-baryon interactions are
described by means of an effective (chirally motivated) separable potential and
its parameters are fitted to the experimental data.


title: Moduli space of stable maps to projective space via GIT

abstract:
  We compare the Kontsevich moduli space of genus 0 stable maps to projective
space with the quasi-map space when $d=3$. More precisely, we prove that when
$d=3$, the obvious birational map from the quasi-map space to the moduli space
of stable maps is the composition of three blow-ups followed by two blow-downs.
Furthermore, we identify the blow-up/down centers explicitly in terms of the
moduli spaces for lower degrees. Using this, we calculate the Betti numbers,
the integral Picard group, and the rational cohomology ring. The degree two
case is worked out as a warm-up.


title: On the recent paper on quark confinement by Tomboulis

abstract:
  We point out missing links in the recent paper by Tomboulis in which he
claims a rigorous proof of quark confinement in 4D lattice gauge theory. We
also discuss if it is possible to correct his proof.


title:
Complete characterization of weak, ultrashort near-UV pulses by spectral
  interferometry

abstract:
  We present a method for a complete characterization of a femtosecond
ultraviolet pulse when a fundamental near-infrared beam is also available. Our
approach relies on generation of second harmonic from the pre-characterized
fundamental, which serves as a reference against which an unknown pulse is
measured using spectral interference (SI). The characterization apparatus is a
modified second harmonic frequency resolved optical gating setup which
additionally allows for taking SI spectrum. The presented method is linear in
the unknown field, simple and sensitive. We checked its accuracy using test
pulses generated in a thick nonlinear crystal, demonstrating the ability to
measure the phase in a broad spectral range, down to 0.1% peak spectral
intensity as well as retrieving pi leaps in the spectral phase.


title:
Non-equilibrium Phase Transitions in Ultrarelativistic Nuclear
  Collisions

abstract:
  Highly excited nuclear matter created in ultrarelativistic heavy-ion
collisions possibly reaches the phase of quark deconfinement. It quickly cools
down and hadronises. We explain that the process of hadronisation may likely be
connected with disintegration into fragments. Observable signals of such a
scenario are proposed.


title:
Fast Estimator of Primordial Non-Gaussianity from Temperature and
  Polarization Anisotropies in the Cosmic Microwave Background II: Partial Sky
  Coverage and Inhomogeneous Noise

abstract:
  In our recent paper (Yadav et al. 2007) we described a fast cubic
(bispectrum) estimator of the amplitude of primordial non-Gaussianity of local
type, f_{NL}, from a combined analysis of the Cosmic Microwave Background (CMB)
temperature and E-polarization observations. In this paper we generalize the
estimator to deal with a partial sky coverage as well as inhomogeneous noise.
Our generalized estimator is still computationally efficient, scaling as
O(N^3/2) compared to the O(N^5/2) scaling of the brute force bispectrum
calculation for sky maps with N pixels. Upcoming CMB experiments are expected
to yield high-sensitivity temperature and E-polarization data. Our generalized
estimator will allow us to optimally utilize the combined CMB temperature and
E-polarization information from these realistic experiments, and to constrain
primordial non-Gaussianity.


title: Moduli stabilization with Fayet-Iliopoulos uplift

abstract:
  In the recent years, phenomenological models of moduli stabilization were
proposed, where the dynamics of the stabilization is essentially
supersymmetric, whereas an O'Rafearthaigh supersymmetry breaking sector is
responsible for the "uplift" of the cosmological constant to zero. We
investigate the case where the uplift is provided by a Fayet-Iliopoulos sector.
We find that in this case the modulus contribution to supersymmetry breaking is
larger than in the previous models. A first consequence of this class of
constructions is for gauginos, which are heavier compared to previous models.
In some of our explicit examples, due to a non-standard gauge-mediation type
negative contribution to scalars masses, the whole superpartner spectrum can be
efficiently compressed at low-energy. This provides an original phenomenology
testable at the LHC, in particular sleptons are generically heavier than the
squarks.


title: Study of event-by-event fluctuations in heavy ion collisions

abstract:
  We propose Kolmogorov-Smirnov test as a means for recognising event-by-event
fluctuations of rapidity distributions in relativistic heavy ion collisions.
Such fluctuations may be induced by the spinodal decomposition of the rapidly
expanding system during the 1st order quark-hadron phase transition.


title:
Highly sensitive and broadband carbon nanotube radio-frequency
  single-electron transistor

abstract:
  We have investigated radio-frequency single-electron transistor (RF-SET)
operation of single-walled carbon nanotube quantum dots in the strong tunneling
regime. At 4.2 K and carrier frequency 754.2 MHz, we reach a charge sensitivity
of 2.3e-6 e/Hz^(1/2) over a bandwidth of 85 MHz. Our results indicate a
gain-bandwidth product of 3.7e13 Hz^(3/2)/e, which is by one order of magnitude
better than for typical RF-SETs.


title:
Functions of Bifans in Context of Multiple Regulatory Motifs in
  Signaling Networks

abstract:
  Representation of intracellular signaling networks as directed graphs allows
for the identification of regulatory motifs. Regulatory motifs are groups of
nodes with the same connectivity structure, capable of processing information.
The bifan motif, made of two source nodes directly cross-regulating two target
nodes, is an over-represented motif in a mammalian cell signaling network and
in transcriptional networks. One example of a bifan is the two MAP-kinases, p38
and JNK that phosphorylate and activate the two transcription factors ATF2 and
Elk-1. We have used a system of coupled ordinary differential equations to
analyze the regulatory capability of this bifan motif by itself, and when it
interacts with other motifs such as positive and negative feedback loops. Our
results indicate that bifans provide temporal regulation of signal propagation
and act as signal sorters, filters, and synchronizers. Bifans that have OR gate
configurations show rapid responses while AND gate bifans can introduce delays
and allow prolongation of signal outputs. Bifans that are AND gates can filter
noisy signal inputs. The p38/JNK-ATF2/Elk-1bifan synchronizes the output of
activated transcription factors. Synchronization is a robust property of bifans
and is exhibited even when the bifan is adjacent to a positive feedback loop.
The presence of the bifan promotes the transcription and translation of the
dual specificity protein phosphatase MKP-1 that inhibits p38 and JNK thus
enabling a negative feedback loop. These results indicate that bifan motifs in
cell signaling networks can contribute to signal processing capability both
intrinsically and by enabling the functions of other regulatory motifs.


title:
De-biasing interferometric visibilities in VLTI-AMBER data of low SNR
  observations

abstract:
  AIMS: We have found that the interferometric visibilities of VLTI-AMBER
observations, extracted via the standard reduction package, are significantly
biased when faint targets are concerned. The visibility biases derive from a
time variable fringing effect (correlated noise) appearing on the detector.
METHODS: We have developed a method to correct this bias that consists in a
subtraction of the extra power due to such correlated noise, so that the real
power spectrum at the spatial frequencies of the fringing artifact can be
restored. RESULTS: This pre-processing procedure is implemented in a software,
called AMDC and available to the community, to be run before the standard
reduction package. Results obtained on simulated and real observations are
presented and discussed.


title: Large voltage from spin pumping in magnetic tunnel junctions

abstract:
  We studied the response of a ferromagnet-insulator-normal metal tunnel
structure under an external oscillating radio frequency (R.F.) magnetic field.
The D. C. voltage across the junction is calculated and is found not to
decrease despite the high resistance of the junction; instead, it is of the
order of $\mu V$ to $100\mu V$, much larger than the experimentally observed
value (100 nano-V) in the "strong coupled" ohmic ferromagnet-normal metal
bilayers. This is consistent with recent experimental results in tunnel
structures, where the voltage is larger than $\mu V$s. The damping and loss of
an external RF field in this structure is calculated.


title: Means and Hermite Interpolation

abstract:
  Let $m_{2}<m_{1}$ be two given nonnegative integers with $n=m_{1}+m_{2}+1$.
For suitably differentiable $f$, we let $P,Q\in \pi_{n}$ be the Hermite
polynomial interpolants to $f$ which satisfy
$P^{(j)}(a)=f^{(j)}(a),j=0,1,...,m_{1}$ and
$P^{(j)}(b)=f^{(j)}(b),j=0,1,...,m_{2},$
$Q^{(j)}(a)=f^{(j)}(a),j=0,1,...,m_{2}$ and
$Q^{(j)}(b)=f^{(j)}(b),j=0,1,...,m_{1}$. Suppose that $f\in C^{n+2}(I)$ with
$f^{(n+1)}(x)\neq 0$ for $x\in (a,b)$. If $m_{1}-m_{2}$ is even, then there is
a unique $x_{0},a<x_{0}<b,$ such that $P(x_{0})=Q(x_{0})$. If $m_{1}-m_{2}$ is
odd, then there is a unique $x_{0},a<x_{0}<b,$ such that
$f(x_{0})=\tfrac{1}{2}(P(x_{0})+Q(x_{0})) $. $x_{0}$ defines a strict,
symmetric mean, which we denote by $M_{f,m_{1},m_{2}}(a,b)$. We prove various
properties of these means. In particular, we show that $f(x)=x^{m_{1}+m_{2}+2}$
yields the arithmetic mean, $f(x)=x^{-1}$ yields the harmonic mean, and
$f(x)=x^{(m_{1}+m_{2}+1)/2}$ yields the geometric mean.


title: Forming an Early O-type Star Through Gas Accretion?

abstract:
  We present high angular resolution ($\sim$ 3$''$) and sensitive 1.3 mm
continuum, cyanogen (CN) and vinyl cyanide (C$_2$H$_3$CN) line observations
made with the Submillimeter Array (SMA) toward one of most highly obscured
objects of the W51 IRS2 region, W51 North. We find that the CN line exhibits a
pronounced inverse P-Cygni profile indicating that the molecular gas is
infalling inwards this object with a mass accretion rate between 4 and 7
$\times$ 10$^{-2}$ M$_\odot$ yr$^{-1}$. The C$_2$H$_3$CN traces an east-west
rotating molecular envelope that surrounds either a single obscured (proto)star
with a kinematic mass of 40 M$_{\odot}$ or a small central cluster of B-type
stars and that is associated with a compact high velocity bipolar outflow
traced by H$_2$O masers and SiO molecular emission. We thus confirm that the
W51 North region is part of the growing list of young massive star forming
regions that have been associated with infalling motions and with large mass
accretion rates ($\sim$ 10$^{-2}$ -- 10$^{-4}$), strengthening the evidence for
massive stars forming with very high accretion rates sufficient to quench the
formation of an UCHII region.


title:
Numerical modeling of 1-D transient poroelastic waves in the
  low-frequency range

abstract:
  Propagation of transient mechanical waves in porous media is numerically
investigated in 1D. The framework is the linear Biot's model with
frequency-independant coefficients. The coexistence of a propagating fast wave
and a diffusive slow wave makes numerical modeling tricky. A method combining
three numerical tools is proposed: a fourth-order ADER scheme with
time-splitting to deal with the time-marching, a space-time mesh refinement to
account for the small-scale evolution of the slow wave, and an interface method
to enforce the jump conditions at interfaces. Comparisons with analytical
solutions confirm the validity of this approach.


title: $\Lambda N$ correlations from the stopped $K^-$ reaction on ${}^4$He

abstract:
  We have investigated correlations of coincident $\Lambda N$ pairs from the
stopped $K^-$ reaction on ${}^4$He, and clearly observed $\Lambda p$ and
$\Lambda n$ branches of the two-nucleon absorption process in the $\Lambda N$
invariant mass spectra. In addition, non-mesonic reaction channels, which
indicate possible exotic signals for the formation of strange multibaryon
states, have been identified.


title:
Development of miniaturized light endoscope-holder robot for
  laparoscopic surgery

abstract:
  PURPOSE: We have conducted experiments with an innovatively designed robot
endoscope holder for laparoscopic surgery that is small and low cost. MATERIALS
AND METHODS: A compact light endoscope robot (LER) that is placed on the
patient's skin and can be used with the patient in the lateral or dorsal supine
position was tested on cadavers and laboratory pigs in order to allow
successive modifications. The current control system is based on voice
recognition. The range of vision is 360 degrees with an angle of 160 degrees .
Twenty-three procedures were performed. RESULTS: The tests made it possible to
advance the prototype on a variety of aspects, including reliability,
steadiness, ergonomics, and dimensions. The ease of installation of the robot,
which takes only 5 minutes, and the easy handling made it possible for 21 of
the 23 procedures to be performed without an assistant. CONCLUSION: The LER is
a camera holder guided by the surgeon's voice that can eliminate the need for
an assistant during laparoscopic surgery. The ease of installation and
manufacture should make it an effective and inexpensive system for use on
patients in the lateral and dorsal supine positions. Randomized clinical trials
will soon validate a new version of this robot prior to marketing.


title:
Renormalized cluster expansion of the microfield distribution in a
  strongly coupled two-component plasmas

abstract:
  The electric microfield distribution (MFD) at an impurity ion is studied for
two-component (TCP) electron-ion plasmas using molecular dynamics simulation
and theoretical models. The particles are treated within classical statistical
mechanics using an electron-ion Coulomb potential regularized at distances less
than the de Broglie length to take into account quantum-diffraction effects.
Corrections to the potential-of-mean-force exponential (PMFEX) approximation
recently proposed for MFD in a strongly coupled TCP [Phys. Rev. E 72, 036403
(2005)] are obtained and discussed. This has been done by a generalization of
the standard Baranger-Mozer and renormalized cluster expansion techniques
originally developed for the one-component plasmas to the TCPs. The results
obtained for a neutral point are compared with those from molecular dynamics
simulations. It is shown that the corrections do not help to improve the PMFEX
approximation for a TCP with low ionic charge Z. But starting with Z > 5 the
PMFEX model is substantially improved and the agreement with numerical
simulations is excellent. We have also found that with increasing coupling the
PMFEX approximation becomes invalid to predict the MFD at a neutral point while
its corrected version agrees satisfactory with the simulations.


title: Effective temperature of active matter

abstract:
  We follow the dynamics of an ensemble of interacting self-propelled motorized
particles in contact with an equilibrated thermal bath. We find that the
fluctuation-dissipation relation allows for the definition of an effective
temperature that is compatible with the results obtained using a tracer
particle as a thermometer. The effective temperature takes a value which is
higher than the temperature of the bath and it is continuously controlled by
the motor intensity.


title: Some aspects of ultra-relativistic heavy ion collisions

abstract:
  In this talk, I discuss some recent results obtained in Heavy Ion Collisions
and what they tell us -- or what questions they raise -- about the physics of
the system of quarks and gluons formed in these collisions.


title: Near-critical percolation in two dimensions

abstract:
  We give a self-contained and detailed presentation of Kesten's results that
allow to relate critical and near-critical percolation on the triangular
lattice. They constitute an important step in the derivation of the exponents
describing the near-critical behavior of this model. For future use and
reference, we also show how these results can be obtained in more general
situations, and we state some new consequences.


title: Irreducible representations of inner quasidiagonal C*-algebras

abstract:
  It is shown that a separable C*-algebra is inner quasidiagonal if and only if
it has a separating family of quasidiagonal irreducible representations. As a
consequence, a separable C*-algebra is a strong NF algebra if and only if it is
nuclear and has a separating family of quasidiagonal irreducible
representations. We also obtain some permanence properties of the class of
inner quasidiagonal C*-algebras.


title: The Ground Scalar Nonet and D Decays

abstract:
  A short review on light scalar mesons is performed both in experiment and
theory. A naive model, constrained by D branching ratios, is derived in order
to make predictions on the wave functions of the $f_0(600)$ and $a_0(980)$
mesons. This leads us to compute transition form factors between the
pseudoscalar $B$ and scalar mesons.


title:
The galaxy luminosity function of the Abell 496 cluster and its spatial
  variations

abstract:
  We investigate the LF in the very relaxed cluster Abell 496. Our analysis is
based on deep images obtained at CFHT with MegaPrime/MegaCam in four bands
(ugri) covering a 1x1 deg2 region, which is centered on the cluster Abell 496
and extends to near its virial radius. The LFs are estimated by statistically
subtracting a reference field taken as the mean of the 4 Deep fields of the
CFHTLS survey. Background contamination is minimized by cutting out galaxies
redder than the observed Red Sequence in the g-i versus i colour-magnitude
diagram. In Abell 496, the global LFs show a faint-end slope alpha=-1.55+/-0.06
and vary little with observing band. Without colour cuts, the LFs are much
noisier but not significantly steeper. The faint-end slopes show a
statistically significant steepening from alpha=-1.4+/-0.1 in the central
region (extending to half a virial radius) to -1.8+/-0.1 in the Southern
envelope of the cluster. Cosmic variance and uncertain star-galaxy separation
are our main limiting factors in measuring the faint-end of the LFs. The
large-scale environment of Abell 496, probed with the fairly complete 6dFGS
catalogue, shows a statistically significant 36 Mpc long filament at PA=137
deg, but we do not find an enhanced LF along this axis. Our LFs do not display
the large number of dwarf galaxies (alpha ~ -2) inferred by several authors,
whose analyses may suffer from field contamination caused by inexistent or
inadequate colour cuts. Alternatively, different clusters may have different
faint-end slopes, but this is hard to reconcile with the wide range of slopes
found for given clusters and for wide sets of clusters.


title: A Kerr interior

abstract:
  An exact solution of the Einstein field equations is proposed which
represents a differentially rotating fluid. As this solution matches the
exterior Kerr solution and reduces to the Schwarzschild interior solution by
setting the rotational parameter to zero, it could serve as Kerr interior.


title: Kerr interior surfaces

abstract:
  A recently found interior for the Kerr metric is re-investigated by means of
geometrical methods. A surface with nonholonomicity is matched to the surface
of the exterior solution.


title:
The Vacuum Fluctuation Theorem: Exact Schroedinger Equation via
  Nonequilibrium Thermodynamics

abstract:
  By assuming that a particle of energy hbar.omega is actually a dissipative
system maintained in a nonequilibrium steady state by a constant throughput of
energy (heat flow), the exact Schroedinger equation is derived, both for
conservative and nonconservative systems. Thereby, only universal properties of
oscillators and nonequilibrium thermostatting are used, such that a maximal
model independence of the hypothesised sub-quantum physics is guaranteed. It is
claimed that this represents the shortest derivation of the Schroedinger
equation from (modern) classical physics in the literature, and the only exact
one, too. Moreover, a "vacuum fluctuation theorem" is presented, with
particular emphasis on possible applications for a better understanding of
quantum mechanical nonlocal effects.


title:
Josephson current and Andreev states in superconductor-half
  metal-superconductor heterostructures

abstract:
  We develop a detailed microscopic theory describing dc Josephson effect and
Andreev bound states in superconducting junctions with a half-metal. In such
systems the supercurrent is caused by triplet pairing states emerging due to
spin-flip scattering at the interfaces between superconducting electrodes and
the half-metal. For sufficiently clean metals we provide a detailed
non-perturbative description of the Josephson current at arbitrary
transmissions and spin-flip scattering parameters for both interfaces. Our
analysis demonstrates that the behavior of both the Josephson current and
Andreev bound states crucially depends on the strength of spin-flip scattering
showing a rich variety of features which can be tested in future experiments.


title: Charmless Hadronic B Decays at BABAR

abstract:
  We report recent measurements of branching fractions and charge asymmetries
of charmless hadronic B decays using the data collected with the BABAR detector
at the PEP-II asymmetric energy e+e- collider.


title: Equality statements for entropy change in open systems

abstract:
  The entropy change of a (non-equilibrium) Markovian ensemble is calculated
from (1) the ensemble phase density $p(t)$ evolved as iterative map, $p(t) =
\mathbb{M}(t) p(t- \Delta t)$ under detail balanced transition matrix
$\mathbb{M}(t)$, and (2) the invariant phase density $\pi(t) =
\mathbb{M}(t)^{\infty} \pi(t) $. A virtual measurement protocol is employed,
where variational entropy is zero, generating exact expressions for
irreversible entropy change in terms of the Jeffreys measure, $\mathcal{J}(t) =
\sum_{\Gamma} [p(t) - \pi(t)] \ln \bfrac{p(t)}{\pi(t)}$, and for reversible
entropy change in terms of the Kullbach-Leibler measure, $\mathcal{D}_{KL}(t) =
\sum_{\Gamma} \pi(0) \ln \bfrac{\pi(0)}{\pi(t)}$. Five properties of
$\mathcal{J}$ are discussed, and Clausius' theorem is derived.


title:
Diffusion Monte Carlo calculations for the ground states of atoms and
  ions in neutron star magnetic fields

abstract:
  The diffusion quantum Monte Carlo method is extended to solve the old
theoretical physics problem of many-electron atoms and ions in intense magnetic
fields. The feature of our approach is the use of adiabatic approximation wave
functions augmented by a Jastrow factor as guiding functions to initialize the
quantum Monte Carlo prodecure. We calcula te the ground state energies of atoms
and ions with nuclear charges from Z= 2, 3, 4, ..., 26 for magnetic field
strengths relevant for neutron stars.


title: Affine actions on Nilpotent Lie groups

abstract:
  To any connected and simply connected nilpotent Lie group N, one can
associate its group of affine transformations Aff(N). In this paper, we study
simply transitive actions of a given nilpotent Lie group G on another nilpotent
Lie group N, via such affine transformations. We succeed in translating the
existence question of such a simply transitive affine action to a corresponding
question on the Lie algebra level. As an example of the possible use of this
translation, we then consider the case where dim(G)=dim(N) less than 6.
  Finally, we specialize to the case of abelian simply transitive affine
actions on a given connected and simply connected nilpotent Lie group. It turns
out that such a simply transitive abelian affine action on N corresponds to a
particular Lie compatible bilinear product on the Lie algebra of N, which we
call an LR-structure.


title: Coherent backscattering of light from saturated atoms

abstract:
  We survey recent progress achieved in understanding the impact of inelastic
processes on coherent backscattering of light from cold atoms that are
saturated by a powerful laser field.


title: Bicartesian Coherence Revisited

abstract:
  A survey is given of results about coherence for categories with finite
products and coproducts. For these results, which were published previously by
the authors in several places, some formulations and proofs are here corrected,
and matters are updated. The categories investigated in this paper formalize
equality of proofs in classical and intuitionistic conjunctive-disjunctive
logic without distribution of conjunction over disjunction.


title: Five-dimensional black holes in heterotic string theory

abstract:
  We review recent results on near-horizon static black hole solutions and
entropy in R^2-corrected N=2 SUGRA in D=5, focusing on actions connected to
heterotic string compactified on K3\times S^1. Comparison with
\alpha'-perturbative results, results obtained by using simple Gauss-Bonnet
R^2-correction, OSV conjecture and microscopic stringy description (for small
black holes) shows that situation in D=5 is, in a sense, even more interesting
then in D=4.


title: On a continuity theorem for constructive functions

abstract:
  One proves that any everywhere defined constructive mapping from a complete
metric space into a complete metric space which preserves the property of
precompacity of subsets is locally uniformly continuous. This fact can be
viewed as interpretation of L. E. J. Brower's fan theorem in terms of A. A.
Markov's constructive analysis.


title: Indexing astronomical database tables using HTM and HEALPix

abstract:
  In various astronomical projects it is crucial to have coordinates indexed
tables. All sky optical and IR catalogues have up to 1 billion objects that
will increase with forthcoming projects. Also partial sky surveys at various
wavelengths can collect information (not just source lists) which can be saved
in coordinate ordered tables. Selecting a sub-set of these entries or
cross-matching them could be un-feasible if no indexing is performed. Sky
tessellation with various mapping functions have been proposed. It is a matter
of fact that the astronomical community is accepting the HTM and HEALPix schema
as the default for object catalogues and for maps visualization and analysis,
respectively. Within the MCS library project, we have now made available as
MySQL-callable functions various HTM and HEALPix facilities. This is made
possible thanks to the capability offered by MySQL 5.1 to add external
plug-ins. The DIF (Dynamic Indexing Facilities) package distributed within the
MCS library, creates and manages a combination of Views, Triggers, DB-engine
and plug-ins allowing the user to deal with database tables indexed using one
or both these pixelisation schema in a completely transparent way.


title:
Lattice study of meson correlators in the epsilon-regime of two-flavor
  QCD

abstract:
  We calculate mesonic two-point functions in the epsilon-regime of two-flavor
QCD on the lattice with exact chiral symmetry. We use gauge configurations of
size 16^3 32 at the lattice spacing a \sim 0.11 fm generated with dynamical
overlap fermions. The sea quark mass is fixed at \sim 3 MeV and the valence
quark mass is varied in the range 1-4 MeV, both of which are in the
epsilon-regime. We find a good consistency with the expectations from the
next-to-leading order calculation in the epsilon-expansion of (partially
quenched) chiral perturbation theory. From a fit we obtain the pion decay
constant F=87.3(5.6) MeV and the chiral condensate Sigma^{MS}=[239.8(4.0) MeV
]^3 up to next-to-next-to-leading order contributions.


title: New formulations for dual equivalent actions

abstract:
  New actions in D=2 and D=3 are proposed that are dual equivalent to known
theories displaying well defined chirality and helicity, respectively, along
with a new interpolating action that maps continuously through the original
dualities. The new chiral action in D=2 is a second-order theory displaying the
chiral constraint dynamically while in D=3 the helicity constraint is imposed a
la Siegel. The resulting theories introduce new versions of the Hull noton to
take care of the symmetry aspects of the original models. The new interpolating
formulation is then re-examined as a condensed phase for the discussion of
duality under the light of the dual mechanisms -- Julia-Toulouse and Higgs --
establishing new interpolating actions in the dilute phase, according to these
mechanisms.


title: Equivalent Hamiltonian for Lee Model

abstract:
  Using the techniques of quasi-Hermitian quantum mechanics and quantum field
theory we use a similarity transformation to construct an equivalent Hermitian
Hamiltonian for the Lee model. In the field theory confined to the $V/N\theta$
sector it effectively decouples $V$, replacing the three-point interaction of
the original Lee model by an additional mass term for the $V$ particle and a
four-point interaction between $N$ and $\theta$. While the construction is
originally motivated by the regime where the bare coupling becomes imaginary,
leading to a ghost, it applies equally to the standard Hermitian regime where
the bare coupling is real. In that case the similarity transformation becomes a
unitary transformation.


title: Meridional flow profile measurements with SOHO/MDI

abstract:
  We present meridional flow measurements of the Sun using a novel helioseismic
approach for analyzing SOHO/MDI data in order to push the current limits in
radial depth. Analyzing three consecutive months of data during solar minimum,
we find that the meridional flow is as expected poleward in the upper
convection zone, turns equatorward at a depth of around 40 Mm (~0.95 Rsol), and
possibly changes direction again in the lower convection zone. This may
indicate two meridional circulation cells in each hemisphere, one beneath the
other.


title: EeV neutrinos associated with UHECR sources

abstract:
  Electromagnetic energy losses of charged pions and muons suppress the
expected high energy, >1E18 eV, neutrino emission from sources of ultrahigh
energy, >1E19 eV, cosmic-rays. We show here that >1E19 eV photons produced in
such sources by neutral pion decay may escape the sources, thanks to the
Klein-Nishina suppression of the pair production cross section, and produce
muon pairs in interactions with the cosmic microwave background. The flux of
muon decay neutrinos, which are expected to be associated in time and direction
with the electromagnetic emission from the sources, may reach a few percent of
the Waxman-Bahcall bound. Their detection may allow one to directly identify
the sources of >1E19 eV cosmic-rays, and will provide the most stringent
constraints on quantum-gravity-induced Lorentz violation.


title: Scarring in open quantum systems

abstract:
  We study scarring phenomena in open quantum systems. We show numerical
evidence that individual resonance eigenstates of an open quantum system
present localization around unstable short periodic orbits in a similar way as
their closed counterparts. The structure of eigenfunctions around these
classical objects is not destroyed by the opening. This is exposed in a
paradigmatic system of quantum chaos, the cat map.


title: Occurrence of exponential relaxation in closed quantum systems

abstract:
  We investigate the occurrence of exponential relaxation in a certain class of
closed, finite systems on the basis of a time-convolutionless (TCL) projection
operator expansion for a specific class of initial states with vanishing
inhomogeneity. It turns out that exponential behavior is to be expected only if
the leading order predicts the standard separation of timescales and if,
furthermore, all higher orders remain negligible for the full relaxation time.
The latter, however, is shown to depend not only on the perturbation
(interaction) strength, but also crucially on the structure of the perturbation
matrix. It is shown that perturbations yielding exponential relaxation have to
fulfill certain criteria, one of which relates to the so-called ``Van Hove
structure''. All our results are verified by the numerical integration of the
full time-dependent Schroedinger equation.


title:
Existence of Asymptotic Expansions in Noncommutative Quantum Field
  Theories

abstract:
  Starting from the complete Mellin representation of Feynman amplitudes for
noncommutative vulcanized scalar quantum field theory, introduced in a previous
publication, we generalize to this theory the study of asymptotic behaviours
under scaling of arbitrary subsets of external invariants of any Feynman
amplitude. This is accomplished for both convergent and renormalized
amplitudes.


title:
Energy absorption of xenon clusters in helium nanodroplets under strong
  laser pulses

abstract:
  Energy absorption of xenon clusters embedded in helium nanodroplets from
strong femtosecond laser pulses is studied theoretically. Compared to pure
clusters we find earlier and more efficient energy absorption in agreement with
experiments. This effect is due to resonant absorption of the helium nanoplasma
whose formation is catalyzed by the xenon core. For very short double pulses
with variable delay both plasma resonances, due to the helium shell and the
xenon core, are identified and the experimental conditions are given which
should allow for a simultaneous observation of both of them.


title: Polarimetry of the dwarf planet (136199) Eris

abstract:
  We investigate the surface characteristics of the large dwarf planet (136199)
Eris. With the FORS1 instrument of the ESO VLT, we have obtained Bessell
broadband R linear polarimetry and broadband V and I photometry. We have
modelled the observations in terms of the coherent-backscattering mechanism to
constrain the surface properties of the object. Polarimetric observations of
Eris show a small negative linear polarization without opposition surge in the
phase angle range of 0.15-0.5 degrees. The photometric data allow us to suppose
a brightness opposition peak at phase angles below 0.2-0.3 degrees. The data
obtained suggest possible similarity to the polarimetric and photometric phase
curves of Pluto. The measured absolute magnitude and broadband colors of Eris
are H_V=-1.15, V-R=0.41, and V-I=0.75.


title:
Resolving the ionized wind of the post-Red Supergiant IRC +10 420 with
  VLTI/AMBER

abstract:
  The paper investigates the milli-arcsecond scale structure of the present-day
mass-loss of the post-Red Supergiant IRC+10420. We use three telescopes of the
VLT Interferometer in combination with the AMBER near-infrared beam combiner to
measure spectrally dispersed correlated fluxes in the K-band around the Br
gamma transition. The resulting visibilities are compared to the predicted
visibilities of emission structures with various simple models in order to
infer the size of the observed emission region. The Br gamma line is resolved
by VLTI+AMBER on all three baselines, with the maximum projected baseline
extending 69 meter and a P.A. ranging between 10 and 30 degrees. A differential
phase between line and continuum is detected on the longest baseline. The Br
gamma emission region is found to have a diameter of 3.3 milli-arcseconds
(FWHM), when compared to a Gaussian intensity distribution. A uniform disk and
a ring-like intensity distribution do not fit the line visibilities. Comparing
the AMBER equivalent width of Br gamma with measurements from various epochs,
we find that the stellar photosphere contributes about 60% of the total
continuum light at 2.2 micron. The remaining 40% continuum emission is found on
scales larger than the 66mas AMBER field of view. Using simple arguments, and
assuming optically thick line emission, we find that the line emitting region
is elongated. We briefly discuss the possibilities whether such a structure is
due to a bi-polar flow or a circumstellar disk. (Abridged).


title: Shapes of Semiflexible Polymers in Confined Spaces

abstract:
  We investigate the conformations of a semiflexible polymer confined to a
square box. Results of Monte Carlo simulations show the existence of a shape
transition when the persistence length of the polymer becomes comparable to the
dimensions of box. An order parameter is introduced to quantify this behavior.
A simple mean-field model is constructed to study the effect of the shape
transition on the effective persistence length of the polymer.


title: Study of errors in strong gravitational lensing

abstract:
  We examine the accuracy of strong gravitational lensing determinations of the
mass of galaxy clusters by comparing the conventional approach with the
numerical integration of the fully relativistic null geodesic equations in the
case of weak gravitational perturbations on Robertson-Walker metrics. In
particular, we study spherically-symmetric, three-dimensional singular
isothermal sphere models and the three-dimensional matter distribution of
Navarro et al. (1997), which are both commonly used in gravitational lensing
studies. In both cases we study two different methods for mass-density
truncation along the line of sight: hard truncation and conventional (no
truncation). We find that the relative error introduced in the total mass by
the thin lens approximation alone is less than 0.3% in the singular isothermal
sphere model, and less than 2% in the model of Navarro et al. (1997). The
removal of hard truncation introduces an additional error of the same order of
magnitude in the best case, and up to an order of magnitude larger in the worst
case studied. Our results ensure that the future generation of precision
cosmology experiments based on lensing studies will not require the removal of
the thin-lens assumption, but they may require a careful handling of
truncation.


title: Jet reshaping in heavy-ion collisions

abstract:
  We propose a new implementation of medium effects in jet structures in which
a modification of the splitting function is included at every step in the
typical final state parton shower. Although the main application of this new
formalism will be at the LHC, it is interesting that, in the presence of a
trigger bias to small number of splittings, non-trivial angular dependences
could appear with shapes similar to those measured experimentally at RHIC in
high-pT particle correlations.


title: Testing the magnetic field models of galaxies with the SKA

abstract:
  The future new-generation radio telescope SKA (Square Kilometre Array) and
its precursors will provide a rapidly growing number of polarized radio
sources. Hundred and thousands polarized background sources can be measured
towards nearby galaxies thus allowing their detailed magnetic field mapping by
means of Faraday rotation measures (RM). We aim to estimate the required
density of the background polarized sources detected with the SKA for reliable
recognition and reconstruction of the magnetic field structure in nearby spiral
galaxies. We construct a galaxy model which includes the ionized gas and
magnetic field patterns of different azimuthal symmetry (axisymmetric (ASS),
bisymmetric (BSS) and quadrisymmetric spiral (QSS), and superpositions) plus a
halo magnetic field. RM fluctuations with a Kolmogorov spectrum due to
turbulent fields and/or fluctuations in ionized gas density are superimposed.
Recognition of magnetic structures is possible from RM towards background
sources behind galaxies or a continuous RM map obtained from the diffuse
polarized emission from the galaxy itself. Under favourite conditions, about a
few dozens of polarized sources are sufficient for a reliable recognition.
Reconstruction of the field structure without precognition becomes possible for
a large number of background sources. A reliable reconstruction of the field
structure needs at least 20 RM values on a cut along the projected minor axis
which translates to approximately 1200 sources towards the galaxy. Radio
telescopes operating at low frequencies (LOFAR, ASKAP and the low-frequency SKA
array) may also be useful instruments for field recognition or reconstruction
with the help of RM, if background sources are still significantly polarized at
low frequencies (abriged).


title: Heavy ion collisions phenomenology overview

abstract:
  The reach of collider energies in heavy-ion collisions has profoundly changed
our understanding of QCD under extreme conditions. I review some these new
developments and comment on the properties of the produced medium as extracted
from experimental data, as well as the exciting new opportunities which will be
open at the LHC.


title:
Polaron relaxation in self-assembled quantum dots: Breakdown of the
  semi-classical model

abstract:
  We calculate the lifetime of conduction band excited states in self-assembled
quantum dots by taking into account LO-phonon-electron interaction and various
anharmonic phonon couplings. We show that polaron relaxation cannot be
accurately described by a semi-classical model. The contributions of different
anharmonic decay channels are shown to depend strongly on the polaron energy.
We calculate the energy dependence of polaron lifetime and compare our results
to available experimental measurements of polaron decay time in InAs/GaAs
quantum dots.


title: Semiclassical Droplet States in Matrix Quantum Hall Effect

abstract:
  We derive semiclassical ground state solutions that correspond to the quantum
Hall states earlier found in the Maxwell-Chern-Simons matrix theory. They
realize the Jain composite-fermion construction and their density is piecewise
constant as that of phenomenological wave functions. These results support the
matrix theory as a possible effective theory of the fractional Hall effect. A
crucial role is played by the constraint limiting the degeneracy of matrix
states: we find its explicit gauge invariant form and clarify its physical
interpretation.


title:
A Method for Compressing Parameters in Bayesian Models with Application
  to Logistic Sequence Prediction Models

abstract:
  Bayesian classification and regression with high order interactions is
largely infeasible because Markov chain Monte Carlo (MCMC) would need to be
applied with a great many parameters, whose number increases rapidly with the
order. In this paper we show how to make it feasible by effectively reducing
the number of parameters, exploiting the fact that many interactions have the
same values for all training cases. Our method uses a single ``compressed''
parameter to represent the sum of all parameters associated with a set of
patterns that have the same value for all training cases. Using symmetric
stable distributions as the priors of the original parameters, we can easily
find the priors of these compressed parameters. We therefore need to deal only
with a much smaller number of compressed parameters when training the model
with MCMC. The number of compressed parameters may have converged before
considering the highest possible order. After training the model, we can split
these compressed parameters into the original ones as needed to make
predictions for test cases. We show in detail how to compress parameters for
logistic sequence prediction models. Experiments on both simulated and real
data demonstrate that a huge number of parameters can indeed be reduced by our
compression method.


title:
Rotation and Macroturbulence in Metal-poor Field Red Giant and Red
  Horizontal Branch Stars

abstract:
  We report the results for rotational velocities, Vrot sin i, and
macroturbulence dispersion, zeta(RT), for 12 metal-poor field red giant branch
stars and 7 metal-poor field red horizontal branch stars. The results are based
on Fourier transform analyses of absorption line profiles from high-resolution
(R ~ 120,000), high-S/N (~ 215 per pixel) spectra obtained with the Gecko
spectrograph at CFHT. We find that the zeta(RT) values for the metal-poor RGB
stars are very similar to those for metal-rich disk giants studied earlier by
Gray and his collaborators. Six of the RGB stars have small rotational values,
less than 2.0 km/sec, while five show significant rotation, over 3 km/sec. The
fraction of rapidly rotating RHB stars is somewhat lower than found among BHB
stars. We devise two empirical methods to translate the line-broadening results
obtained by Carney et al. (2003, 2008) into Vrot sin i for all the RGB and RHB
stars they studied. Binning the RGB stars by luminosity, we find that most
metal-poor field RGB stars show no detectable sign, on average, of rotation.
However, the most luminous stars, with M(V) <= -1.5, do show net rotation, with
mean values of 2 to 4 km/sec, depending on the algorithm employed, and these
stars also show signs of radial velocity jitter and mass loss.


title:
Subalgebras of Lie algebras with non-degenerate restriction of the
  Killing form

abstract:
  Let $\mf{g}$ be any finite-dimensional Lie algebra with Killling form $B$.
Let $\mf{h}$ be a subalgebra of $\mf{g}$ on which the Killing form is non
degenerate. Then $\mf{h}$ is reductive.


title:
On highly transcendental quantities which cannot be expressed by
  integral formulas

abstract:
  E565 in the Enestrom index. Translated from the Latin original, "De plurimis
quantitatibus transcendentibus quas nullo modo per formulas integrales
exprimere licet" (1775).
  Euler does not prove any results in this paper. It seems to me like he is
trying to develop some general ideas about special functions. He gives some
examples of numbers he claims but does not prove cannot be represented by
definite integrals of algebraic functions. Euler has the idea that if we knew
more about the function with the power series $\sum x^{t_n}$ where $t_n$ is the
$n$th triangular number, this could lead to a proof of Fermat's theorem that
every positive integer is the sum of three triangular numbers. This doesn't end
of being fruitful for Euler, but in fact later Jacobi proves a lot of results
like this with his theta functions. The last paragraph (\S 9) is not clear to
me. My best reading is that there are infinitely many "levels" of
transcendental numbers and that this is unexpected or remarkable.


title:
Okubo-Zweig-Iizuka-rule violation and B\to \eta^{(\prime)}K branching
  ratios

abstract:
  We show that few-percent Okubo-Zweig-Iizuka-rule violating effects in the
quark-flavor basis for the $\eta$-$\eta'$ mixing can enhance the chiral scale
associated with the $\eta_q$ meson few times. This enhancement is sufficient
for accommodating the dramatically different data of the $B\to\eta^{\prime} K$
and $B\to\eta K$ branching ratios. We comment on other proposals for resolving
this problem, including flavor-singlet contributions, axial U(1) anomaly, and
nonperturbative charming penguins. Discrimination of the above proposals by
means of the $B\to\eta^{(\prime)}\ell\nu$ and $B_s\to\eta^{(\prime)}\ell\ell$
data is suggested.


title:
Detection of an inner gaseous component in a Herbig Be star accretion
  disk: Near- and mid-infrared spectro-interferometry and radiative transfer
  modeling of MWC 147

abstract:
  We study the geometry and the physical conditions in the inner (AU-scale)
circumstellar region around the young Herbig Be star MWC 147 using
long-baseline spectro-interferometry in the near-infrared (NIR K-band,
VLTI/AMBER observations and PTI archive data) as well as the mid-infrared (MIR
N-band, VLTI/MIDIobservations). The emission from MWC 147 is clearly resolved
and has a characteristic physical size of approx. 1.3 AU and 9 AU at 2.2 micron
and 11 micron respectively (Gaussian diameter). The spectrally dispersed AMBER
and MIDI interferograms both show a strong increase in the characteristic size
towards longer wavelengths, much steeper than predicted by analytic disk models
assuming power-law radial temperature distributions. We model the
interferometric data and the spectral energy distribution of MWC 147 with 2-D,
frequency-dependent radiation transfer simulations. This analysis shows that
models of spherical envelopes or passive irradiated Keplerian disks (with
vertical or curved puffed-up inner rim) can easily fit the SED, but predict
much lower visibilities than observed; the angular size predicted by such
models is 2 to 4 times larger than the size derived from the interferometric
data, so these models can clearly be ruled out. Models of a Keplerian disk with
optically thick gas emission from an active gaseous disk (inside the dust
sublimation zone), however, yield a good fit of the SED and simultaneously
reproduce the absolute level and the spectral dependence of the NIR and MIR
visibilities. We conclude that the NIR continuum emission from MWC 147 is
dominated by accretion luminosity emerging from an optically thick inner
gaseous disk, while the MIR emission also contains contributions from the
outer, irradiated dust disk.


title: The Local Hubble Flow: Is it a Manifestation of Dark Energy?

abstract:
  To study the local Hubble flow, we have run constrained dark matter
  (DM) simulations of the Local Group (LG) in the concordance LCDM and OCDM
cosmologies, with identical cosmological parameters apart from the Lambda term.
The simulations were performed within a computational box of 64 h^{-1}Mpc
centred on the LG. The initial conditions were constrained by the observed
peculiar velocities of galaxies and positions of X-ray nearby clusters of
galaxies. The simulations faithfully reproduce the nearby large scale
structure, and in particular the Local Supercluster and the Virgo cluster.
LG-like objects have been selected from the DM halos so as to closely resemble
the dynamical properties of the LG. Both the LCDM and OCDM simulations show
very similar local Hubble flow around the LG-like objects. It follows that,
contrary to recent statements, the dark energy (DE) does not manifest itself in
the local dynamics.


title: Finding the growth rate of a regular language in polynomial time

abstract:
  We give an O(n^3+n^2 t) time algorithm to determine whether an NFA with n
states and t transitions accepts a language of polynomial or exponential
growth. We also show that given a DFA accepting a language of polynomial
growth, we can determine the order of polynomial growth in quadratic time.


title: Laser experiments explore the hidden sector

abstract:
  Recently, the laser experiments BMV and GammeV, searching for light shining
through walls, have published data and calculated new limits on the allowed
masses and couplings for axion-like particles. In this note we point out that
these experiments can serve to constrain a much wider variety of hidden-sector
particles such as, e.g., minicharged particles and hidden-sector photons. The
new experiments improve the existing bounds from the older BFRT experiment by a
factor of two. Moreover, we use the new PVLAS constraints on a possible
rotation and ellipticity of light after it has passed through a strong magnetic
field to constrain pure minicharged particle models. For masses <~0.05 eV, the
charge is now restricted to be less than (3-4)x10^(-7) times the electron
electric charge. This is the best laboratory bound and comparable to bounds
inferred from the energy spectrum of the cosmic microwave background.


title: Isoscaling, Symmetry Energy and Thermodynamic Models

abstract:
  The isoscaling parameter usually denoted by $\alpha$ depends upon both the
symmetry energy coefficient and the isotopic contents of the dissociating
systems. We compute $\alpha$ in theoretical models: first in a simple mean
field model and then in thermodynamic models using both grand canonical and
canonical ensembles. For finite systems the canonical ensemble is much more
appropriate. The model values of $\alpha$ are compared with a much used
standard formula. Next we turn to cases where in experiments, there are
significant deviations from isoscaling. We show that in such cases, although
the grand canonical model fails, the canonical model is capable of explaining
the data.


title:
Majorana Neutrinos, Neutrino Mass Spectrum and the |<m>| ~ 0.001 eV
  Frontier in Neutrinoless Double Beta Decay

abstract:
  If future neutrino oscillation experiments show that the neutrino mass
spectrum is with normal ordering, m1 < m2 < m3, and the searches for
neutrinoless double beta-decay with sensitivity to values of the effective
Majorana mass |<m>| > 0.01 eV give negative results, the next frontier in the
quest for neutrinoless double beta-decay will correspond to |<m>| ~ 0.001 eV.
Assuming that massive neutrinos are Majorana particles and their exchange is
the dominant mechanism generating neutrinoless double beta-decay, we analise
the conditions under which |<m>|, in the case of three neutrino mixing and
neutrino mass spectrum with normal ordering, would satisfy |<m>| > 0.001 eV. We
consider the specific cases of i) normal hierarchical neutrino mass spectrum,
ii) of relatively small value of the CHOOZ angle theta13 as well as iii) the
general case of spectrum with normal ordering, partial hierarchy and a value of
theta13 close to the existing upper limit. We study the ranges of the lightest
neutrino mass m1 and/or of sin^2 theta13, for which |<m>|> 0.001 eV and discuss
the phenomenological implications of such scenarios. We provide also an
estimate of |<m>| when the three neutrino masses and the neutrino mixing
originate from neutrino mass term of Majorana type for the (left-handed)
flavour neutrinos and m1 Ue1^2 + m2 U_e2^2 + m3 Ue3^2 =0, but there does not
exist a symmetry which forbids the neutrinoless double beta-decay.


title:
Near threshold production of the pseudoscalar mesons at the COSY-11
  facility

abstract:
  We summarise measurements of the COSY-11 collaboration concerning the
excitation functions of the near threshold pseudoscalar meson production in the
proton-proton interaction. The results are discussed in the context of the
meson-nucleon and hyperon-nucleon interactions. We conclude that the
$\eta$-proton interaction is significantly stronger than the eta'-proton
interaction. Similarly, we found that the hyperon Lambda interacts with the
nucleon considerably stronger than the hyperon Sigma, and that the interaction
of (K-)-proton is much stronger than this of the (K+)-proton.


title:
Vigorous star formation with low efficiency in massive disk galaxies at
  z=1.5

abstract:
  We present the first detection of molecular gas cooling CO emission lines
from ordinary massive galaxies at z=1.5. Two sources were observed with the
IRAM Plateau de Bure Interferometer, selected to lie in the mass-star formation
rate correlation at their redshift, thus being representative of massive high-z
galaxies. Both sources were detected with high confidence, yielding
L'_CO~10^{10}K km/s pc^2. For one of the sources we find evidence for velocity
shear, implying CO sizes of ~10 kpc. With an infrared luminosity of
L_FIR~10^{12}L_sun, these disk-like galaxies are borderline ULIRGs but with
star formation efficiency similar to that of local spirals, and an order of
magnitude lower than that in submm galaxies. This suggests a CO to total gas
conversion factor similar to local spirals, gas consumption timescales
approaching 1 Gyr or longer and molecular gas masses reaching ~10^11 M_sun,
comparable to or larger than the estimated stellar masses. These results
support a major role of 'in situ' gas consumption over cosmological timescales
and with relatively low star formation efficiency, analogous to that of local
spiral disks, for the formation of today's most massive galaxies and their
central black holes. Given the high space density of similar galaxies,
~10^{-4}/Mpc^3, this implies a widespread presence of gas rich galaxies in the
early Universe, many of which might be within reach of detailed investigations
of current and planned facilities.


title: Dark Matter Candidates: A Ten-Point Test

abstract:
  An extraordinarily rich zoo of non-baryonic Dark Matter candidates has been
proposed over the last three decades. Here we present a 10-point test that a
new particle has to pass, in order to be considered a viable DM candidate: I.)
Does it match the appropriate relic density? II.) Is it {\it cold}? III.) Is it
neutral? IV.) Is it consistent with BBN? V.) Does it leave stellar evolution
unchanged? VI.) Is it compatible with constraints on self-interactions? VII.)
Is it consistent with {\it direct} DM searches? VIII.) Is it compatible with
gamma-ray constraints? IX.) Is it compatible with other astrophysical bounds?
X.) Can it be probed experimentally?


title: Highest-Energy Cosmic Rays and Hilbertian Repulsive Effect

abstract:
  We point out that an important portion of the high energy of the cosmic rays
from extragalactic sources can be attributed to a Hilbertian repulsive effect,
which is a consequence of Einstein equations without cosmological term.


title:
Dynamics of the near threshold eta meson production in proton-proton
  interaction

abstract:
  We present the results of measurements of the analysing power for the p(pol)p
--> pp eta reaction at the excess energies of Q=10 and 36 MeV, and interpret
these results within the framework of the meson exchange models. The determined
values of the analysing power at both excess energies are consistent with zero
implying that the eta meson is produced predominantly in s-wave.


title: On the Ramsey multiplicity of complete graphs

abstract:
  We show that, for $n$ large, there must exist at least
\[\frac{n^t}{C^{(1+o(1))t^2}}\] monochromatic $K_t$s in any two-colouring of
the edges of $K_n$, where $C \approx 2.18$ is an explicitly defined constant.
The old lower bound, due to Erd\H{o}s \cite{E62}, and based upon the standard
bounds for Ramsey's theorem, is \[\frac{n^t}{4^{(1+o(1))t^2}}.\]


title:
Critical temperature for first-order phase transitions in confined
  systems

abstract:
  We consider the Euclidean $D$-dimensional $-\lambda |\phi |^4+\eta |\phi |^6$
($\lambda ,\eta >0 $) model with $d$ ($d\leq D$) compactified dimensions.
Introducing temperature by means of the Ginzburg--Landau prescription in the
mass term of the Hamiltonian, this model can be interpreted as describing a
first-order phase transition for a system in a region of the $D$-dimensional
space, limited by $d$ pairs of parallel planes, orthogonal to the coordinates
axis $x_1, x_2, ..., x_d$. The planes in each pair are separated by distances
$L_1, L_2, ..., L_d$. We obtain an expression for the transition temperature as
a function of the size of the system, $% T_c(\{L_i\})$, $i=1, 2, ..., d$. For
D=3 we particularize this formula, taking $L_1=L_2=... =L_d=L$ for the
physically interesting cases $d=1$ (a film), $d=2$ (an infinitely long wire
having a square cross-section), and for $d=3$ (a cube). For completeness, the
corresponding formulas for second-order transitions are also presented.
Comparison with experimental data for superconducting films and wires shows
qualitative agreement with our theoretical expressions

categories: cond-mat.soft cond-mat.supr-con hep-ph hep-th


title: Complex hyperbolic hyperplane complements

abstract:
  We study spaces obtained from a complete finite volume complex hyperbolic
n-manifold M by removing a compact totally geodesic complex (n-1)-submanifold.
The main result is that the fundamental group of M-S is relatively hyperbolic,
relative to fundamental groups of the ends of M-S, and M-S admits a complete
finite volume A-regular Riemannian metric of negative sectional curvature. It
follows that for n>1 the fundamental group of M-S satisfies Mostow-type
Rigidity, has finite asymptotic dimension and rapid decay property, satisfies
Borel and Baum-Connes conjectures, is co-Hopf and residually hyperbolic, has no
nontrivial subgroups with property (T), and has finite outer automorphism
group. Furthermore, if M is compact, then the fundamental group of M-S is
biautomatic and satisfies Strong Tits Alternative.


title:
A nearly-optimal method to compute the truncated theta function, its
  derivatives, and integrals

abstract:
  A poly-log time method to compute the truncated theta function, its
derivatives, and integrals is presented. The method is elementary, rigorous,
explicit, and suited for computer implementation. We repeatedly apply the
Poisson summation formula to the truncated theta function while suitably
normalizing the linear and quadratic arguments after each repetition. The
method relies on the periodicity of the complex exponential, which enables the
suitable normalization of the arguments, and on the self-similarity of the
Gaussian, which ensures that we still obtain a truncated theta function after
each application of the Poisson summation. In other words, our method relies on
modular properties of the theta function. Applications to the numerical
computation of the Riemann zeta function and to finding the number of solutions
of Waring type Diophantine equations are discussed.


title: Contact equations, Lipschitz extensions and isoperimetric inequalities

abstract:
  We characterize locally Lipschitz mappings and existence of Lipschitz
extensions through a first order nonlinear system of PDEs. We extend this study
to graded group-valued Lipschitz mappings defined on compact Riemannian
manifolds. Through a simple application, we emphasize the connection between
these PDEs and the Rumin complex. We introduce a class of 2-step groups,
satisfying some abstract geometric conditions and we show that Lipschitz
mappings taking values in these groups and defined on subsets of the plane
admit Lipschitz extensions. We present several examples of these groups, called
Allcock groups, observing that their horizontal distribution may have any
codimesion. Finally, we show how these Lipschitz extensions theorems lead us to
quadratic isoperimetric inequalities in all Allcock groups.


title: A note on lower bounds for hypergraph Ramsey numbers

abstract:
  We improve upon the lower bound for 3-colour hypergraph Ramsey numbers,
showing, in the 3-uniform case, that \[r_3 (l,l,l) \geq 2^{l^{c \log \log
l}}.\] The old bound, due to Erd\H{o}s and Hajnal, was \[r_3 (l,l,l) \geq 2^{c
l^2 \log^2 l}.\]


title: Fast methods to compute the Riemann zeta function

abstract:
  The Riemann zeta function on the critical line can be computed using a
straightforward application of the Riemann-Siegel formula, Sch\"onhage's
method, or Heath-Brown's method. The complexities of these methods have
exponents 1/2, 3/8 (=0.375), and 1/3 respectively. In this paper, three new
fast and potentially practical methods to compute zeta are presented. One
method is very simple. Its complexity has exponent 2/5. A second method relies
on this author's algorithm to compute quadratic exponential sums. Its
complexity has exponent 1/3. The third method employs an algorithm, developed
in this paper, to compute cubic exponential sums. Its complexity has exponent
4/13 (approximately, 0.307).


title: Black hole formation and slow-roll inflation

abstract:
  Black hole formation may occur if the spectrum of the curvature perturbation
\zeta increases strongly as the scale decreases. As no such increase is
observed on cosmological scales, black hole formation requires strongly
positive running n' of the spectral index n, though the running might only kick
in below the `cosmological scales' probed by the CMB anisotropy and galaxy
surveys. A concrete and well-motivated way of producing this running is through
the running mass model of slow roll inflation. We obtain a new observational
bound n' < 0.026 on the running provided by this model, improving an earlier
result by a factor two. We also discuss black hole production in more general
scenarios. We show that the usual conditions \epsilon << 1 and |\eta| << 1 are
enough to derive the spectrum {\cal P}_{\zeta}(k), the introduction of higher
order parameters \xi^{2} etc. being optional.


title: A bound on the exponent of the cohomology of BC-bundles

abstract:
  We give a lower bound for the exponent of certain elements in the integral
cohomology of the total spaces of principal BC-bundles for C a finite cyclic
group. As applications we give a proof of the theorem of A. Adem and H.-W. Henn
that a p-group is elementary abelian if and only if its integral cohomology has
exponent p, and we exhibit some infinite groups of finite virtual cohomological
dimension whose Tate-Farrell cohomology contains torsion of order greater than
the l.c.m. of the orders of their finite subgroups. We also give an upper bound
for the exponent of all but finitely many of the integral cohomology groups of
a finite group, in terms of the permutation representations of the group.


title:
Smoothness criteria for Navier-Stokes equations in terms of regularity
  along the steam lines

abstract:
  This article is devoted to a regularity criteria for solutions of the
Navier-Stokes equations in terms of regularity along the stream lines. More
precisely, we prove that a suitable weak solution for the Navier-Stokes
equations is regular under some constraint on the second derivative of |u|
along the stream lines.


title: The Yagita invariant of general linear groups

abstract:
  We give a definition of the Yagita invariant at a prime p of an arbitrary
group G, and compute the invariant for each prime for the general linear groups
over any integrally closed subring of the complex numbers. We also compute the
invariants for special linear groups over the same rings, except in some cases
when both the degree of the linear group and the ring are `small' compared to
p.


title:
Massless Sine-Gordon and Massive Thirring Models: proof of the Coleman's
  equivalence

abstract:
  We prove the Coleman's conjecture on the equivalence between the massless
Sine-Gordon model with finite volume interaction and the Thirring model with a
finite volume mass term.


title: On subgroups of Coxeter groups

abstract:
  A right-angled Coxeter group is a group with a given set of generators of
order two, subject only to the relations that certain pairs of the generators
commute. Various papers have shown how homological properties of the Coxeter
group are related to homological properties of the simplicial complex whose
simplices are the sets of commuting generators.
  Using these techniques, we construct torsion-free groups which are Poincare
duality groups over some rings but not over others, and a group whose integral
cohomological dimension is finite but strictly greater than its cohomological
dimension over any field.
  We determine which Coxeter groups have finite virtual cohomological dimension
(it is classical that all finitely generated Coxeter groups have finite vcd,
but there are others). We also give minimal presentations for certain
torsion-free finite-index subgroups of right-angled Coxter groups. Finally we
give a `bare-hands' construction (using free products with amalgamation and HNN
extensions) of a torsion-free group whose integral cohomological dimension is
strictly greater than its rational cohomological dimension.


title: High-energy gravitational scattering and black hole resonances

abstract:
  Aspects of super-planckian gravitational scattering and black hole formation
are investigated, largely via a partial-wave representation. At large and
decreasing impact parameters, amplitudes are expected to be governed by single
graviton exchange, and then by eikonalized graviton exchange, for which
partial-wave amplitudes are derived. In the near-Schwarzschild regime,
perturbation theory fails. However, general features of gravitational
scattering associated with black hole formation suggest a particular form for
amplitudes, which we express as a black hole ansatz. We explore features of
this ansatz, including its locality properties. These amplitudes satisfy
neither the Froissart bound, nor apparently the more fundamental property of
polynomial boundedness, through which locality is often encoded in an S-matrix
framework. Nevertheless, these amplitudes do satisfy a macroscopic form of
causality, expressed as a polynomial bound for the forward-scattering
amplitude.


title: Chern classes and extraspecial groups

abstract:
  The mod-p cohomology ring of the extraspecial p-group of exponent p is
studied for odd p. We investigate the subquotient ch(G) generated by Chern
classes modulo the nilradical. The subring of ch(G) generated by Chern classes
of one-dimensional representations was studied by Tezuka and Yagita. The
subring generated by the Chern classes of the faithful irreducible
representations is a polynomial algebra. We study the interplay between these
two families of generators, and obtain some relations between them.


title: On universally stable elements

abstract:
  We show that certain subrings of the cohomology of a finite p-group P may be
realised as the images of restriction from suitable virtually free groups. We
deduce that the cohomology of P is a finite module for any such subring.
Examples include the ring of `universally stable elements' defined by Evens and
Priddy, and rings of invariants such as the mod-2 Dickson algebras.


title: One-loop Integral Coefficients from Generalized Unitarity

abstract:
  I describe a method for determining the coefficients of scalar integrals for
one-loop amplitudes in quantum field theory. The method is based upon
generalized unitarity and the behavior of amplitudes when the free parameters
of the cut momenta approach infinity. The method works for arbitrary masses of
both external and internal legs of the amplitudes. It therefore applies not
only to QCD but also to the Electroweak theory and to quantum field theory in
general.


title: On the GL(V)-module structure of K(n)^*(BV)

abstract:
  We study the question of whether the Morava K-theory of the classifying space
of an elementary abelian group V is a permutation module (in either of two
distinct senses) for the automorphism group of V. We use Brauer characters and
computer calculations.
  We construct and implement an algorithm for finding permutation submodules of
maximal dimension inside modules for p-groups in characteristic p.


title: On the integral cohomology of wreath products

abstract:
  Under mild conditions on the space X, we describe the additive structure of
the integral cohomology of the space $X^p \times_{C_p}EC_p$ in terms of the
cohomology of X. We give weaker results for other similar spaces, and deduce
various corollaries concerning the cohomology of finite groups.


title: The cohomology of Bestvina-Brady groups

abstract:
  For each subcomplex of the standard CW-structure on any torus, we compute the
homology of a certain infinite cyclic regular covering space. In all cases when
the homology is finitely generated, we also compute the cohomology ring. For
aspherical subcomplexes of the torus our computation gives the homology and
cohomology of Bestvina-Brady groups. We compute the cohomological dimension of
each of these groups over any field and over any subring of the rationals.


title:
Comparative study of the growth of sputtered aluminum oxide films on
  organic and inorganic substrates

abstract:
  We present a comparative study of the growth of the technologically highly
relevant gate dielectric and encapsulation material aluminum oxide in inorganic
and also organic heterostructures. Atomic force microscopy studies indicate
strong similarities in the surface morphology of aluminum oxide films grown on
these chemically different substrates. In addition, from X-ray reflectivity
measurements we extract the roughness exponent \beta of aluminum oxide growth
on both substrates. By renormalising the aluminum oxide roughness by the
roughness of the underlying organic film we find good agreement with \beta as
obtained from the aluminum oxide on silicon oxide (\beta = 0.38 \pm 0.02),
suggesting a remarkable similarity of the aluminum oxide growth on the two
substrates under the conditions employed.


title: The cohomology of certain groups

abstract: Computations in the cohomology of finite groups.


title:
Controlling the optical properties of transparent media by mixing active
  and passive resonances

abstract:
  Novel optical phenomena, including electromagnetically induced transparency,
slow light, superluminal light propagation, have recently been demonstrated in
diverse physical implementations. These phenomena are challenging to realize in
practical systems because they require quantum coherence as well as careful
preparation and control of prescribed quantum states. Here we present a unified
approach to engineering optical materials that exhibit these phenomena by using
mixtures of active and passive optical materials at frequencies near their
resonances. Our approach does not depend on quantum coherence and can realize
large and small (much less than 1) indices of refraction and negative
permittivity ($\epsilon<0$), normal and anomalous dispersion, all while
maintaining transparency.


title:
Non-local dilaton coupling to dark matter: cosmic acceleration and
  pressure backreaction

abstract:
  A model of non-local dilaton interactions, motivated by string duality
symmetries, is applied to a scenario of "coupled quintessence" in which the
dilaton dark energy is non-locally coupled to the dark-matter sources. It is
shown that the non-local effects tend to generate a backreaction which -- for
strong enough coupling -- can automatically compensate the acceleration due to
the negative pressure of the dilaton potential, thus asymptotically restoring
the standard (dust-dominated) decelerated regime. This result is illustrated by
analytical computations and numerical examples.


title:
K^0 - \bar K^0, B^0 - \bar B^0 mixings in the MSSM with explicit CP
  violation in the Higgs sector

abstract:
  We consider the K^0 - \bar K^0 and B^0 - \bar B^0 mixings in the MSSM with
the two-Higgs-doublet scalar sector featuring explicit CP violation, and the
Yukawa sector of type II. In the case of strong mixing between CP-odd and
CP-even states the existence of light charged Higgs is allowed in the model.
The mass splitting \Delta m_{LS} and the amount of indirect CP violation
\epsilon are calculated. In the limit of effective low-energy approximation the
nonstandard effects are shown to be negligibly small in \Delta m_{LS} and
\epsilon for the K^0-mesons, being almost independent on the charged Higgs
boson mass. However, for the B_d^0 - \bar B_d^0 and B_s^0 - \bar B_s^0 systems
the effects of nonstandard physics are shown to be larger, limiting the MSSM
parameter space.


title: Strange two-baryon interactions using chiral effective field theory

abstract:
  We have constructed the leading order strangeness S=-1,-2 baryon-baryon
potential in a chiral effective field theory approach. The chiral potential
consists of one-pseudoscalar-meson exchanges and non-derivative four-baryon
contact terms. The potential, derived using SU(3)_f symmetry constraints,
contains six independent low-energy coefficients. We have solved a regularized
Lippmann-Schwinger equation and achieved a good description of the available
scattering data. Furthermore a correctly bound hypertriton has been obtained.


title:
Reply to comment by Y. Ando on "Onset of Boson Mode at the
  Superconducting Critical Point of Underdoped YBa$_2$Cu$_3$O$_y$" by N.
  Doiron-Leyraud et al

abstract:
  In a recent Comment [arXiv:0711.4654], Y. Ando raises two valid issues in
relation to our low-temperature heat transport study of YBa$_2$Cu$_3$O$_y$
across the insulator-to-superconductor boundary: 1) the possible role of twin
boundaries in scattering phonons; 2) the best fitting procedure for extracting
a fermionic (linear) term from the data. In this Reply, we show that both
concerns can be laid to rest by 1) using new data from a tetragonal (twin-free)
sample, and 2) using an analysis that does not involve any fitting.


title:
Domain wall pinning and potential landscapes created by constrictions
  and protrusions in ferromagnetic nanowires

abstract:
  The potential experienced by transverse domain walls (TDWs) in the vicinity
of asymmetric constrictions or protrusions in thin Permalloy nanowires is
probed using spatially resolved magneto-optical Kerr effect measurements. Both
types of traps are found to act as pinning centers for DWs. The strength of
pinning is found to depend on the trap type as well as on the chirality of the
incoming DW; both types of traps are seen to act either as potential wells or
potential barriers, also depending on the chirality of the DW. Micromagnetic
simulations have been performed that are in good qualitative agreement with the
experimental results.


title: Merger Histories of Galaxy Halos and Implications for Disk Survival

abstract:
  We study the merger histories of galaxy dark matter halos using a high
resolution LCDM N-body simulation. Our merger trees follow ~17,000 halos with
masses M_0 = (10^11--10^13) Msun at z=0 and track accretion events involving
objects as small as m = 10^10 Msun. We find that mass assembly is remarkably
self-similar in m/M_0, and dominated by mergers that are ~10% of the final halo
mass. While very large mergers, m > 0.4 M_0, are quite rare, sizeable accretion
events, m ~ 0.1 M_0, are common. Over the last 10 Gyr, an overwhelming majority
(~95%) of Milky Way-sized halos with M_0 = 10^12 Msun have accreted at least
one object with greater total mass than the Milky Way disk (m > 5x10^10 Msun),
and approximately 70% have accreted an object with more than twice that mass (m
> 10^11 Msun). Our results raise serious concerns about the survival of
thin-disk dominated galaxies within the current paradigm for galaxy formation
in a CDM universe. In order to achieve a ~70% disk-dominated fraction in Milky
Way-sized CDM halos, mergers involving m ~ 2x10^11 Msun objects must not
destroy disks. Considering that most thick disks and bulges contain old stellar
populations, the situation is even more restrictive: these mergers must not
heat disks or drive gas into their centers to create young bulges.


title:
The p-adic closure of a subgroup of rational points on a commutative
  algebraic group

abstract:
  Let G be a commutative algebraic group over Q. Let Gamma be a subgroup of
G(Q) contained in the union of the compact subgroups of G(Q_p). We formulate a
guess for the dimension of the closure of Gamma in G(Q_p), and show that its
correctness for certain tori is equivalent to Leopoldt's conjecture.


title:
Perturbation theory and excursion set estimates of the probability
  distribution function of dark matter, and a method for reconstructing the
  initial distribution function

abstract:
  Nonlinear evolution can sometimes be modelled by a deterministic mapping from
initial to final of the local smoothed overdensity. Perturbation theory methods
base on this deterministic and local mapping and ignore the 'cloud-in-cloud'
effect, while the excursion set approach methods take this nonlocality into
account. We compared these methods using the spherical collapse mapping and
showed that, on scales where the rms fluctuation is small, both models give
similar results and they are in good agreement with numerical simulations. If
the deterministic mapping depends on quantities other than overdensity, this
will also manifest as stochasticity if the other quantities are ignored. We
considered the Zeldovich approximation and Ellipsoidal Collapse model, both
include the tidal field in the evolution. Our anaylsis shows that the change in
cell shape effect should be included on scales where the rms is of order of
unity or larger. On scales where the rms is less than 2 methods based on the
spherical collapse model allow a rather accurate reconstruction of the shape of
the initial distribution from the nonlinear field. This can be used as the
basis for constraining the statistical properties of the initial fluctuation
field. (Abridge)


title: The Computation of the Logarithmic Cohomology for Plane Curves

abstract:
  We give algorithms of computing bases of logarithmic cohomology groups for
square-free polynomials in two variables. (Fixed typos of v1)


title: New classification techniques for ordinary differential equations

abstract:
  The goal of the present paper is to propose an enhanced ordinary differential
equations solver by exploitation of the powerful equivalence method of \'Elie
Cartan. This solver returns a target equation equivalent to the equation to be
solved and the transformation realizing the equivalence. The target ODE is a
member of a dictionary of ODE, that are regarded as well-known, or at least
well-studied. The dictionary considered in this article are ODE in a book of
Kamke. The major advantage of our solver is that the equivalence transformation
is obtained without integrating differential equations. We provide also a
theoretical contribution revealing the relationship between the change of
coordinates that maps two differential equations and their symmetry
pseudo-groups.


title:
The Galaxy Cross-Correlation Function as a Probe of the Spatial
  Distribution of Galactic Satellites

abstract:
  The spatial distribution of satellite galaxies around host galaxies can
illuminate the relationship between satellites and dark matter subhalos and aid
in developing and testing galaxy formation models. Previous efforts to
constrain the distribution attempted to eliminate interlopers from the measured
projected number density of satellites and found that the distribution is
generally consistent with the expected dark matter halo profile of the parent
hosts, with a best-fit power-law slope of ~ -1.7 between projected separations
of ~30 kpc/h and 0.5 Mpc/h. Here, I use the projected cross-correlation of
bright and faint galaxies to analyze contributions from satellites and
interlopers together, using a halo occupation distribution (HOD) analytic model
for galaxy clustering. This approach is tested on mock catalogs constructed
from simulations. I find that analysis of Sloan Digital Sky Survey (SDSS) data
gives results generally consistent with interloper subtraction methods between
the projected separations of 10 kpc/h and 6.3 Mpc/h, although the errors on the
parameters that constrain the radial profile are large, and larger samples of
data are required.


title: The On/Off Nature of Star-Planet Interactions

abstract:
  Evidence suggesting an observable magnetic interaction between a star and its
hot Jupiter appears as a cyclic variation of stellar activity synchronized to
the planet's orbit. In this study, we monitored the chromospheric activity of 7
stars with hot Jupiters using new high-resolution echelle spectra collected
with ESPaDOnS over a few nights in 2005 and 2006 from the CFHT. We searched for
variability in several stellar activity indicators (Ca II H, K, the Ca II
infrared triplet, Halpha, and He I). HD 179949 has been observed almost every
year since 2001. Synchronicity of the Ca II H & K emission with the orbit is
clearly seen in four out of six epochs, while rotational modulation with
P_rot=7 days is apparent in the other two seasons. We observe a similar
phenomenon on upsilon And, which displays rotational modulation (P_rot=12 days)
in September 2005, in 2002 and 2003 variations appear to correlate with the
planet's orbital period. This on/off nature of star-planet interaction (SPI) in
the two systems is likely a function of the changing stellar magnetic field
structure throughout its activity cycle. Variability in the transiting system
HD 189733 is likely associated with an active region rotating with the star,
however, the flaring in excess of the rotational modulation may be associated
with its hot Jupiter. As for HD 179949, the peak variability as measured by the
mean absolute deviation for both HD 189733 and tau Boo leads the sub-planetary
longitude by 70 degrees. The tentative correlation between this activity and
the ratio of Mpsini to the planet's rotation period, a quantity proportional to
the hot Jupiter's magnetic moment, first presented in Shkolnik et al. 2005
remains viable. This work furthers the characterization of SPI, improving its
potential as a probe of extrasolar planetary magnetic fields.


title:
Absence of a Diffusion Anomaly in Water Perpendicular to Hydrophobic
  Nanoconfining Walls

abstract:
  We perform molecular dynamics simulations to investigate the diffusive motion
of TIP5P water in the direction perpendicular to the two hydrophobic confining
walls. To calculate the diffusion coefficient, we use the concept of the
characteristic residence time which is calculated from the exponential decay of
the residence time probability distribution function. We find that a diffusion
anomaly of water, increase of diffusion upon compression, is absent in the
direction perpendicular to the confining walls down to the lowest temperature
we simulate, 220K, whereas there is a diffusion anomaly, similar to that in
bulk water, in the direction parallel to the walls. The absence of a diffusion
anomaly may arise mainly due to nanoconfinement, rather than due to the
hydrophobic property of the confining walls.


title:
Solitary wave trains in granular chains: Experiments, theory and
  simulations

abstract:
  The features of solitary waves observed in horizontal monodisperse chain of
barely touching beads not only depend on geometrical and material properties of
the beads but also on the initial perturbation provided at the edge of the
chain. An impact of a large striker on a monodisperse chain, and similarly a
sharp decrease of bead radius in a stepped chain, generates a solitary wave
train containing many single solitary waves ordered by decreasing amplitudes.
We find, by simple analytical arguments, that the unloading of compression
force at the chain edge has a nearly exponential decrease. The characteristic
time is mainly a function involving the grains' masses and the striker mass.
Numerical calculations and experiments corroborate these findings.