title: Observational bounds on the cosmic radiation density

abstract:
  We consider the inference of the cosmic radiation density, traditionally
parameterised as the effective number of neutrino species N_eff, from precision
cosmological data. Paying particular attention to systematic effects, notably
scale-dependent biasing in the galaxy power spectrum, we find no evidence for a
significant deviation of N_eff from the standard value of N_eff^0=3.046 in any
combination of cosmological data sets, in contrast to some recent conclusions
of other authors. The combination of all available data in the linear regime
prefers, in the context of a ``vanilla+N_eff'' cosmological model,
1.1<N_eff<4.8 (95% C.L.) with a best-fit value of 2.6. Adding data at smaller
scales, notably the Lyman-alpha forest, we find 2.2<N_eff<5.8 (95% C.L.) with
3.8 as the best fit. Inclusion of the Lyman-alpha data shifts the preferred
N_eff upwards because the sigma_8 value derived from the SDSS Lyman-alpha data
is inconsistent with that inferred from CMB. In an extended cosmological model
that includes a nonzero mass for N_eff neutrino flavours, a running scalar
spectral index and a w parameter for the dark energy, we find 0.8<N_eff<6.1
(95% C.L.) with 3.0 as the best fit.


title: Resonant Kelvin-Helmholtz modes in sheared relativistic flows

abstract:
  Qualitatively new aspects of the (linear and non-linear) stability of sheared
relativistic (slab) jets are analyzed. The linear problem has been solved for a
wide range of jet models well inside the ultrarelativistic domain (flow Lorentz
factors up to 20; specific internal energies $\approx 60c^2$). As a distinct
feature of our work, we have combined the analytical linear approach with
high-resolution relativistic hydrodynamical simulations, which has allowed us
i) to identify, in the linear regime, resonant modes specific to the
relativistic shear layer ii) to confirm the result of the linear analysis with
numerical simulations and, iii) more interestingly, to follow the instability
development through the non-linear regime. We find that very high-order
reflection modes with dominant growth rates can modify the global, long-term
stability of the relativistic flow. We discuss the dependence of these resonant
modes on the jet flow Lorentz factor and specific internal energy, and on the
shear layer thickness. The results could have potential applications in the
field of extragalactic relativistic jets.


title:
Bremsstrahlung photon polarization for $ee^\pm\to (e\gamma)e^\pm$, and
  $ep\to (e\gamma)p$ high energy collisions

abstract:
  The polarization of bremsstrahlung photon in the processes $ee^\pm\to
(e\gamma)e^\pm$, and $ep\to (e\gamma)p$ is calculated for peripheral
kinematics, in the high energy limit where the cross section does not decrease
with the incident energy. When the initial electron is
unpolarized(longitudinally polarized) the final photon can be linearly
(circularly) polarized. The Stokes parameters of the photon polarization are
calculated as a function of the kinematical variables of process: the energy of
recoil particle, the energy fraction of scattered electron, and the polar and
azimuthal angles of photon. Numerical results are given in form of tables, for
typical values of the relevant kinematic variables.


title: Higgs and Top quark coupled with a conformal gauge sector

abstract:
  We propose a dynamical scenario beyond the standard model, in which the
radiative correction to the Higgs mass parameter is suppressed due to a large
anomalous dimension induced through a conformal invariant coupling with an
extra gauge sector. Then the anomalous dimension also suppresses the Yukawa
couplings of the Higgs field. However, the large top Yukawa coupling can be
generated effectively through mixing among top quarks and the fermions of the
conformal gauge sector. This scenario is found to predict a fairly heavy Higgs
mass of about 500 GeV. We present an explicit model and show consistency with
the Electro-Weak precision measurements of the S and T parameters as well as
the Z boson decay width.


title: On Black Hole Remnants

abstract:
  We introduce two models for a planck scale black hole remnant (Planckon),
which can hold arbitrarily large information, while keeping a vanishing
coupling and discuss their physical properties.


title: Very Light Cosmological Scalar Fields from a Tiny Cosmological Constant

abstract:
  We discuss a mechanism which generates a mass term for a scalar field in an
expanding universe. The mass of this field turns out to be generated by the
cosmological constant and can be naturally small if protected by a conformal
symmetry which is however broken in the gravitational sector. The mass is
comparable today to the Hubble time. This scalar field could thus impact our
universe today and for example be at the origin of a time variation of the
couplings and masses of the parameters of the standard model.


title: Quasars Lensed by Globular Clusters of Spiral and Elliptical Galaxies

abstract:
  Based on the SDSS catalog, we have found new close quasar-galaxy pairs.
Quasars projected onto the halos of nearer galaxies are encountered among the
multitude of quasars observed at various distances from us. Among them there
are quasars that are close to the galaxies not only in angular separation, but
also in redshift. Such quasar-galaxy pairs are called close pairs. We developed
further the hypothesis that such pairs appear, because the fluxer on the
nucleus of the more distant galaxy passes through halo globular clusters of the
nearer galaxy,resulting in magnification and splitting of the image of the
source that we interpret as a quasar. To corroborate this hypothesis, we
analyzed the distribution of quasars in the plane of the halos of these
galaxies. The quasars from close pairs were found to follow the density profile
of globular clusters in the halos of elliptical and spiral galaxies with slopes
of -1.5 and -2.4 for elliptical and spiral galaxies, respectively. This
suggests that quasars do not appear near galaxies by chance and that quasars
are associated with galaxies via halo globular clusters.


title: SDSSJ104341.53+085558.2: A second white dwarf with a gaseous debris disc

abstract:
  Intermediate resolution spectroscopy of the white dwarf
SDSSJ104341.53+085558.2 contains double-peaked emission lines of
CaII8498,8542,8662 and identifies this object to be the second single white
dwarf to be surrounded by a gaseous disc of metal-rich material, similar to the
recently discovered SDSSJ1228+1040. A photospheric Magnesium abundance of 0.3
times the solar value, determined from the observed MgII4481 absorption line,
implies that the white dwarf is accreting from the circumstellar material. The
absence of Balmer emission lines and of photospheric HeI4471 absorption
indicates that the accreted material is depleted in volatile elements and, by
analogy with SDSS1228+1040, may be the result of the tidal disruption of an
asteroid. Additional spectroscopy of the DAZ white dwarfs WD1337+705 and GD362
does not reveal CaII emission lines. GD362 is one of the few cool DAZ that
display strong infrared flux excess, thought to be originating in a
circumstellar dust disc, and its temperature is likely too low to sublimate
sufficient amounts of disc material to generate detectable CaII emission.
WD1337+705 is, as SDSS1228+1040 and SDSS1043+0855, moderately hot, but has the
lowest Mg abundance of those three stars, suggesting a possible correlation
between the photospheric Mg abundance and the equivalent width of the CaII
emission triplet. Our inspection of 7360 white dwarfs from SDSS DR4 fails to
unveil additional strong "metal gas disc" candidates, and implies that these
objects are rather rare.


title:
Helicity generation and alpha-effect by Vandakurov-Tayler instability
  with z-dependent differential rotation

abstract:
  We investigate in isothermal MHD simulations the instability of toroidal
magnetic fields resulting by the action of z-dependent differential rotation on
a given axial field B^0 in a cylindrical enclosure where in particular the
helicity of the resulting nonaxisymmetric flow is of interest. The idea is
probed that helicity H is related to the external field and the differential
rotation as H ~ B^0_i B^0_j Omega_i,j. The observed instability leads to a
nonaxisymmetric solution with dominating mode m=1. With the onset of
instability both kinematic and current helicity are produced which fulfill the
suggested relation. Obviously, differential rotation dOmega/dz only needs an
external axial field B^0_z to produce remarkable amounts of the helicities. Any
regular time-dependency of the helicity could not be found. The resulting axial
alpha-effect is mainly due to the current helicity, the characteristic time
scale between both the values is of order of the rotation time. If the axial
field is switched off then the helicity and the alpha-effect disappear.


title: Multiresolution Approximation of Polygonal Curves in Linear Complexity

abstract:
  We propose a new algorithm to the problem of polygonal curve approximation
based on a multiresolution approach. This algorithm is suboptimal but still
maintains some optimality between successive levels of resolution using dynamic
programming. We show theoretically and experimentally that this algorithm has a
linear complexity in time and space. We experimentally compare the outcomes of
our algorithm to the optimal "full search" dynamic programming solution and
finally to classical merge and split approaches. The experimental evaluations
confirm the theoretical derivations and show that the proposed approach
evaluated on 2D coastal maps either show a lower time complexity or provide
polygonal approximations closer to the input discrete curves.


title:
VOODB: A Generic Discrete-Event Random Simulation Model to Evaluate the
  Performances of OODBs

abstract:
  Performance of object-oriented database systems (OODBs) is still an issue to
both designers and users nowadays. The aim of this paper is to propose a
generic discrete-event random simulation model, called VOODB, in order to
evaluate the performances of OODBs in general, and the performances of
optimization methods like clustering in particular. Such optimization methods
undoubtedly improve the performances of OODBs. Yet, they also always induce
some kind of overhead for the system. Therefore, it is important to evaluate
their exact impact on the overall performances. VOODB has been designed as a
generic discrete-event random simulation model by putting to use a modelling
approach, and has been validated by simulating the behavior of the O2 OODB and
the Texas persistent object store. Since our final objective is to compare
object clustering algorithms, some experiments have also been conducted on the
DSTC clustering technique, which is implemented in Texas. To validate VOODB,
performance results obtained by simulation for a given experiment have been
compared to the results obtained by benchmarking the real systems in the same
conditions. Benchmarking and simulation performance evaluations have been
observed to be consistent, so it appears that simulation can be a reliable
approach to evaluate the performances of OODBs.


title: On a two-dimensional analog of Szemeredi's Theorem in Abelian groups

abstract:
  Let G be a finite Abelian group and A be a subset G\times G of cardinality at
least |G|^2/(log log |G|)^c, where c>0 is an absolute constant. We prove that A
contains a triple {(k,m), (k+d,m), (k,m+d)}, where d does not equal 0. This
theorem is a two-dimensional generalization of Szemeredi's theorem on
arithmetic progressions.


title: Parallel Transport and Functors

abstract:
  Parallel transport of a connection in a smooth fibre bundle yields a functor
from the path groupoid of the base manifold into a category that describes the
fibres of the bundle. We characterize functors obtained like this by two
notions we introduce: local trivializations and smooth descent data. This
provides a way to substitute categories of functors for categories of smooth
fibre bundles with connection. We indicate that this concept can be generalized
to connections in categorified bundles, and how this generalization improves
the understanding of higher dimensional parallel transport.


title:
OCB: A Generic Benchmark to Evaluate the Performances of Object-Oriented
  Database Systems

abstract:
  We present in this paper a generic object-oriented benchmark (the Object
Clustering Benchmark) that has been designed to evaluate the performances of
clustering policies in object-oriented databases. OCB is generic because its
sample database may be customized to fit the databases introduced by the main
existing benchmarks (e.g., OO1). OCB's current form is clustering-oriented
because of its clustering-oriented workload, but it can be easily adapted to
other purposes. Lastly, OCB's code is compact and easily portable. OCB has been
implemented in a real system (Texas, running on a Sun workstation), in order to
test a specific clustering policy called DSTC. A few results concerning this
test are presented.


title:
Performance Evaluation for Clustering Algorithms in Object-Oriented
  Database Systems

abstract:
  It is widely acknowledged that good object clustering is critical to the
performance of object-oriented databases. However, object clustering always
involves some kind of overhead for the system. The aim of this paper is to
propose a modelling methodology in order to evaluate the performances of
different clustering policies. This methodology has been used to compare the
performances of three clustering algorithms found in the literature (Cactis, CK
and ORION) that we considered representative of the current research in the
field of object clustering. The actual performance evaluation was performed
using simulation. Simulation experiments we performed showed that the Cactis
algorithm is better than the ORION algorithm and that the CK algorithm totally
outperforms both other algorithms in terms of response time and clustering
overhead.


title: Nonequilibrium fluctuations in small systems: From physics to biology

abstract:
  In this paper I am presenting an overview on several topics related to
nonequilibrium fluctuations in small systems. I start with a general discussion
about fluctuation theorems and applications to physical examples extracted from
physics and biology: a bead in an optical trap and single molecule force
experiments. Next I present a general discussion on path thermodynamics and
consider distributions of work/heat fluctuations as large deviation functions.
Then I address the topic of glassy dynamics from the perspective of
nonequilibrium fluctuations due to small cooperatively rearranging regions.
Finally, I conclude with a brief digression on future perspectives.


title: The Dagum family of isotropic correlation functions

abstract:
  A function $\rho:[0,\infty)\to(0,1]$ is a completely monotonic function if
and only if $\rho(\Vert\mathbf{x}\Vert^2)$ is positive definite on
$\mathbb{R}^d$ for all $d$ and thus it represents the correlation function of a
weakly stationary and isotropic Gaussian random field. Radial positive definite
functions are also of importance as they represent characteristic functions of
spherically symmetric probability distributions. In this paper, we analyze the
function \[\rho(\beta ,\gamma)(x)=1-\biggl(\frac{x^{\beta}}{1+x^{\beta}}\biggr
)^{\gamma},\qquad x\ge 0, \beta,\gamma>0,\] called the Dagum function, and show
those ranges for which this function is completely monotonic, that is, positive
definite, on any $d$-dimensional Euclidean space. Important relations arise
with other families of completely monotonic and logarithmically completely
monotonic functions.


title: The level 1 case of Serre's conjecture revisited

abstract:
  We prove existence of conjugate Galois representations, and we use it to
derive a simple method of weight reduction. As a consequence, an alternative
proof of the level 1 case of Serre's conjecture follows.


title: The accessory parameter problem in positive characteristic

abstract:
  We study the existence of Fuchsian differential equations in positive
characteristic with nilpotent p-curvature, and given local invariants. In the
case of differential equations with logarithmic local mononodromy, we determine
the minimal possible degree of a polynomial solution.


title:
Bianchi Type-I Cosmological Models with Variable G and 4\Lambda$-Terms
  in General Relativity

abstract:
  Einstein's field equations with variable gravitational and cosmological
``constant'' are considered in presence of perfect fluid for Bianchi type-I
spacetime. Consequences of the four cases of the phenomenological decay of
$\Lambda$ have been discussed which are consistent with observations. The
physical significance of the cosmological models have also been discussed.


title: Origin of magnetoelectric behavior in BiFeO$_3$

abstract:
  The magnetoelectric behavior of BiFeO$_3$ has been explored on the basis of
accurate density functional calculations. The structural, electronic, magnetic,
and ferroelectric properties of BiFeO$_3$ are predicted correctly without
including strong correlation effect in the calculation. Moreover, the
experimentally-observed elongation of cubic perovskite-like lattice along the
[111] direction is correctly reproduced. At high pressure we predicted a
pressure-induced structural transition and the total energy calculations at
expanded lattice show two lower energy ferroelectric phases, closer in energy
to the ground state phase. Band-structure calculations show that BiFeO$_3$ will
be an insulator in A- and G-type antiferromagnetic phases and a metal in other
magnetic configurations. Chemical bonding in BiFeO$_3$ has been analyzed using
various tools and electron localization function analysis shows that
stereochemically active lone-pair electrons at the Bi sites are responsible for
displacements of the Bi atoms from the centro-symmetric to the
noncentrosymmetric structure and hence the ferroelectricity. A large
ferroelectric polarization (88.7 $\mu$C/cm$^{2}$) is predicted in accordance
with recent experimental findings. The net polarization is found to mainly ($>$
98%) originate from Bi atoms. Moreover the large scatter in experimentally
reported polarization values is due to the large anisotropy in the spontaneous
polarization.


title:
A cold metal-poor cloud traced by a weak MgII absorption at z~0.45.
  First detection of SiI, CaI and FeI in a QSO absorber

abstract:
  We present the observations of a weak MgII absorption system detected at
z~0.452 in the UVES high resolution spectrum of the QSO HE0001-2340. The weaker
of the two MgII components forming the system shows associated absorptions due
to SiI, CaI and FeI observed for the first time in a QSO spectrum. We
investigate the nature of this absorber by comparing its properties with those
of different classes of absorbers (weak MgII, Damped Ly-alpha systems and local
interstellar clouds) and reproducing its ionization conditions with
photoionization models. The observed absorber belongs to the class of weak MgII
systems on the basis of its equivalent width, however the relative strength of
commonly observed transitions deviates significantly from those of the above
mentioned absorbers. A rough estimate of the probability to cross such a system
with a QSO line of sight is P~0.03. The presence of rare neutral transitions
suggests that the cloud is shielded by a large amount of neutral hydrogen. A
detailed comparison of the observed column densities with the average
properties of damped Ly-alpha systems and local interstellar cold clouds shows,
in particular, deficient MgII/MgI and CaII/CaI ratios in our cloud. The results
of photoionization models indicate that the cloud could be ionized by the UV
background. However, a simple model of a single cloud with uniform density
cannot reproduce the observed ionic abundance ratios, suggesting a more complex
density structure for the absorber. Supposing that ionization corrections are
negligible, the most puzzling result is the underabundance of magnesium with
respect to iron which is hard to explain both with nucleosynthesis and with
differential dust depletion. [Abridged]


title: Resource modalities in game semantics

abstract:
  The description of resources in game semantics has never achieved the
simplicity and precision of linear logic, because of a misleading conception:
the belief that linear logic is more primitive than game semantics. We advocate
instead the contrary: that game semantics is conceptually more primitive than
linear logic. Starting from this revised point of view, we design a categorical
model of resources in game semantics, and construct an arena game model where
the usual notion of bracketing is extended to multi- bracketing in order to
capture various resource policies: linear, afﬁne and exponential.


title: Threshold Resummation in Semi-Inclusive B decays

abstract:
  We discuss threshold resummation in radiative and charmless semileptonic B
decays. To deal with the large non perturbative effects, we introduce a model
for NNLL resummed form factors based on the analytic QCD coupling. By means of
this model we can reproduce with good accuracy the experimental data. Finally
we briefly present an improved threshold resummed formula to deal with jets
initiated by massive quarks as in the case of semileptonic charmed decays.


title: Order in the chaos? The strange case of accreting millisecond pulsars

abstract:
  We review recent results from the X-ray timing of accreting millisecond
pulsars in Low Mass X-ray Binaries. This is the first time a timing analysis is
performed on accreting millisecond pulsars, and for the first time we can
obtain information on the behavior of a very fast pulsar subject to accretion
torques. We find both spin-up and spin-down behaviors, from which, using
available models for the accretion torques, we derive information on the mass
accretion rate and magnetic field of the neutron star in these systems. We also
find that the phase delays behavior as a function of time in these sources is
sometimes quite complex and difficult to interpret, since phase shifts, most
probably driven by variations of the X-ray flux, are sometimes present.


title:
Birefringence and non-transversality of light propagation in an
  ultra-strongly magnetized vacuum

abstract:
  The birefringence phenomenon in the vacuum with a constant magnetic
background of arbitrary strength is considered within the framework of the
effective action approach. A new feature of the birefringence in a magnetized
vacuum is that the parallel mode, which is polarized parallel to the plane
containing the magnetic field and the photon wave vector, is no longer
transverse. We have studied this feature in detail for arbitrary magnetic field
and provided analytic results for the ultra-strong magnetic field regime.
Possible physical implications of our results in astrophysics are discussed.


title: When are Swing options bang-bang and how to use it

abstract:
  In this paper we investigate a class of swing options with firm constraints
in view of the modeling of supply agreements. We show, for a fully general
payoff process, that the premium, solution to a stochastic control problem, is
concave and piecewise affine as a function of the global constraints of the
contract. The existence of bang-bang optimal controls is established for a set
of constraints which generates by affinity the whole premium function. When the
payoff process is driven by an underlying Markov process, we propose a
quantization based recursive backward procedure to price these contracts. A
priori error bounds are established, uniformly with respect to the global
constraints.


title: Many Random Walks Are Faster Than One

abstract:
  We pose a new and intriguing question motivated by distributed computing
regarding random walks on graphs: How long does it take for several independent
random walks, starting from the same vertex, to cover an entire graph? We study
the cover time - the expected time required to visit every node in a graph at
least once - and we show that for a large collection of interesting graphs,
running many random walks in parallel yields a speed-up in the cover time that
is linear in the number of parallel walks. We demonstrate that an exponential
speed-up is sometimes possible, but that some natural graphs allow only a
logarithmic speed-up. A problem related to ours (in which the walks start from
some probabilistic distribution on vertices) was previously studied in the
context of space efficient algorithms for undirected s-t connectivity and our
results yield, in certain cases, an improvement upon some of the earlier
bounds.


title: The Rahman Polynomials Are Bispectral

abstract:
  In a very recent paper, M. Rahman introduced a remarkable family of
polynomials in two variables as the eigenfunctions of the transition matrix for
a nontrivial Markov chain due to M. Hoare and M. Rahman. I indicate here that
these polynomials are bispectral. This should be just one of the many
remarkable properties enjoyed by these polynomials. For several challenges,
including finding a general proof of some of the facts displayed here the
reader should look at the last section of this paper.


title:
Improved short-range correlations and 0nbb nuclear matrix elements of
  76Ge and 82Se

abstract:
  We calculate the nuclear matrix elements of the neutrinoless double beta
($0\nu\beta\beta$) decays of $^{76}$Ge and $^{82}$Se for the light-neutrino
exchange mechanism. The nuclear wave functions are obtained by using realistic
two-body forces within the proton-neutron quasiparticle random-phase
approximation (pnQRPA). We include the effects that come from the finite size
of a nucleon, from the higher-order terms of nucleonic weak currents, and from
the nucleon-nucleon short-range correlations. Most importantly, we improve on
the presently available calculations by replacing the rudimentary Jastrow
short-range correlations by the more advanced unitary correlation operator
method (UCOM). The UCOM corrected matrix elements turn out to be notably larger
in magnitude than the Jastrow corrected ones. This has drastic consequences for
the detectability of $0\nu\beta\beta$ decay in the present and future double
beta experiments.


title:
Systematic uncertainties of hadron parameters obtained with QCD sum
  rules

abstract:
  We study the uncertainties of the determination of the ground-state
parameters from Shifman-Vainshtein-Zakharov (SVZ) sum rules, making use of the
harmonic-oscillator potential model as an example. In this case, one knows the
exact solution for the polarization operator $\Pi(\mu)$, which allows one to
obtain both the OPE to any order and the spectrum of states. We start with the
OPE for $\Pi(\mu)$ and analyze the extraction of the square of the ground-state
wave function, $R\propto|\Psi_0(\vec r=0)|^2$, from an SVZ sum rule, setting
the mass of the ground state $E_0$ equal to its known value and treating the
effective continuum threshold as a fit parameter. We show that in a limited
``fiducial'' range of the Borel parameter there exists a solution for the
effective threshold which precisely reproduces the exact $\Pi(\mu)$ for any
value of $R$ within the range $0.7 \le R/R_0 \le 1.15$ ($R_0$ is the known
exact value). Thus, the value of $R$ extracted from the sum rule is determined
to a great extent by the contribution of the hadron continuum. Our main finding
is that in the cases where the hadron continuum is not known and is modeled by
an effective continuum threshold, the systematic uncertainties of the sum-rule
procedure cannot be controlled.


title: Observing the gas temperature drop in the high-density nucleus of L 1544

abstract:
  Abridged: The thermal structure of a starless core is crucial for our
understanding of the physics in these objects and hence for our understanding
of star formation. Theory predicts a gas temperature drop in the inner 5000 AU
of these objects, but there has been little observational proof of this. We
performed VLA observations of the NH3 (1,1) and (2,2) transitions towards the
pre-stellar core L 1544 in order to measure the temperature gradient between
the high density core nucleus and the surrounding core envelope. Our VLA
observation for the first time provide measurements of gas temperature in a
core with a resolution smaller than 1000 AU. We have also obtained high
resolution Plateau de Bure observations of the 110 GHz 111-101 para-NH2D line
in order to further constrain the physical parameters of the high density
nucleus. We have estimated the temperature gradient using a model of the source
to fit our data in the u,v plane. We find that indeed the temperature decreases
toward the core nucleus from 12 K down to 5.5 K resulting in an increase of a
factor of 50% in the estimated density of the core from the dust continuum if
compared with the estimates done with constant temperature of 8.75 K. We also
found a remarkably high abundance of deuterated ammonia with respect to the
ammonia abundance (50%+-20%), which proves the persistence of nitrogen bearing
molecules at very high densities (2e6 cm-3) and shows that high-resolution
observations yield higher deuteration values than single-dish observations. Our
analysis of the NH3 and NH2D kinematic fields shows a decrease of specific
angular momentum from the large scales to the small scales.


title: Simple connectedness of quasitilted algebras

abstract:
  Let A be a basic connected finite dimensional algebra over an algebraically
closed field. Assuming that A is quasitilted, we prove that A is simply
connected if and only if its first Hochschild cohomology group HH^1(A)
vanishes. This generalises a result of I. Assem, F.U. Coelho and S. Trepode and
which proves the same equivalence for tame quasitilted algebras.


title: Cosmological energy in a thermo-horizon and the first law

abstract:
  We consider a cosmological horizon, named thermo-horizon, to which are
associated a temperature and an entropy of Bekenstein-Hawking and which obeys
the first law for an energy flow calculated through the corresponding limit
surface. We point out a contradiction between the first law and the definition
of the total energy contained inside the horizon. This contradiction is removed
when the first law is replaced by a Gibbs' equation for a vacuum-like component
associated to the event horizon.


title:
Domain imaging and domain wall propagation in (Ga,Mn)As thin films with
  tensile strain

abstract:
  We have performed spatially resolved Polar Magneto-Optical Kerr Effect
Microscopy measurements on as-grown and annealed Ga0.95Mn0.05As thin films with
tensile strain. We find that the films exhibit very strong perpendicular
magnetic anisotropy which is increased upon annealing. During magnetic
reversal, the domain walls propagate along the direction of surface ripples for
the as-grown sample at low temperatures and along the [110] direction for the
annealed sample. This indicates that the magnetic domain pattern during
reversal is determined by a combination of magnetocrystalline anisotropy and a
distribution of pinning sites along the surface ripples that can be altered by
annealing. These mechanisms could lead to an effective method of controlling
domain wall propagation.


title: Production of trans-Neptunian binaries through chaos-assisted capture

abstract:
  The recent discovery of binary objects in the Kuiper-belt opens an invaluable
window into past and present conditions in the trans-Neptunian part of the
Solar System. For example, knowledge of how these objects formed can be used to
impose constraints on planetary formation theories. We have recently proposed a
binary-object formation model based on the notion of chaos-assisted capture.
Here we present a more detailed analysis with calculations performed in the
spatial (three-dimensional) three- and four-body Hill approximations. It is
assumed that the potential binary partners are initially following heliocentric
Keplerian orbits and that their relative motion becomes perturbed as these
objects undergo close encounters. First, the mass, velocity, and orbital
element distribu- tions which favour binary formation are identified in the
circular and elliptical Hill limits. We then consider intruder scattering in
the circular Hill four-body problem and find that the chaos-assisted capture
mechanism is consistent with observed, apparently randomly distributed, binary
mutual orbit inclinations. It also predicts asymmetric distributions of
retrograde versus prograde orbits. The time-delay induced by chaos on particle
transport through the Hill sphere is analogous to the formation of a resonance
in a chemical reaction. Implications for binary formation rates are considered
and the 'fine-tuning' problem recently identified by Noll et al. (2007) is also
addressed.


title: Automorphism groups and anti-pluricanonical curves

abstract:
  We show the existence of an anti-pluricanonical curve on every smooth
projective rational surface X which has an infinite group G of automorphisms of
either null entropy or of type Z . Z (semi-direct product), provided that the
pair (X, G) is minimal. This was conjectured by Curtis T. McMullen (2005) and
further traced back to Marat Gizatullin and Brian Harbourne (1987). We also
prove (perhaps) the strongest form of the famous Tits alternative theorem.


title: Penguin-mediated B_(d,s)->VV decays and the Bs - anti-Bs mixing angle

abstract:
  In this letter, we propose three different strategies to extract the weak
mixing angle phi_s of the Bs system using penguin-mediated decays into vectors,
mainly Bs->K*K*, Bs->phi K* and Bs->phi phi. We also provide predictions for
the longitudinal branching ratio and CP-asymmetries of Bs->K*K* using a method
that combines QCD factorisation with flavour symmetries to relate this decay to
its Bd counterpart.


title: The Dark Matter Puzzle And Other Issues

abstract:
  We consider the problem of the flattening of the velocity curves in galactic
discs and the consequent postulation of dark matter from three different but
converging perspectives-- a change in the large scale dimensionality of space,
a variation of $G$ and the MOND approach. We also discuss the paradigm of the
universe itself being a Black Hole.


title:
The AMIGA sample of isolated galaxies. IV. A catalogue of neighbours
  around isolated galaxies

abstract:
  Studies of the effects of environment on galaxy properties and evolution
require well defined control samples. Such isolated galaxy samples have up to
now been small or poorly defined. The AMIGA project (Analysis of the
interstellar Medium of Isolated GAlaxies) represents an attempt to define a
statistically useful sample of the most isolated galaxies in the local (z <
0.05) Universe. A suitable large sample for the AMIGA project already exists,
the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973; 1050 galaxies),
and we use this sample as a starting point to refine and perform a better
quantification of its isolation properties. Digitised POSS-I E images were
analysed out to a minimum projected radius R > 0.5 Mpc around 950 CIG galaxies
(those within Vr = 1500 km s-1 were excluded). We identified all galaxy
candidates in each field brighter than B = 17.5 with a high degree of
confidence using the LMORPHO software. We generated a catalogue of
approximately 54 000 potential neighbours (redshifts exist for 30% of this
sample). Six hundred sixty-six galaxies pass and two hundred eighty-four fail
the original CIG isolation criterion. The available redshift data confirm that
our catalogue involves a largely background population rather than physically
associated neighbours. We find that the exclusion of neighbours within a factor
of four in size around each CIG galaxy, employed in the original isolation
criterion, corresponds to Delta Vr ~ 18000 km s-1 indicating that it was a
conservative limit. Galaxies in the CIG have been found to show different
degrees of isolation. We conclude that a quantitative measure of this is
mandatory. It will be the subject of future work based on the catalogue of
neighbours obtained here.


title: Large Scale Intermittency in the Atmospheric Boundary Layer

abstract:
  We find actual evidence, relying upon vorticity time series taken in a high
Reynolds number atmospheric experiment, that to a very good approximation the
surface boundary layer flow may be described, in a statistical sense and under
certain regimes, as an advected ensemble of homogeneous turbulent systems,
characterized by a lognormal distribution of fluctuating intensities. Our
analysis suggests that usual direct numerical simulations of homogeneous and
isotropic turbulence, performed at moderate Reynolds numbers, may play an
important role in the study of turbulent boundary layer flows, if supplemented
with appropriate statistical information concerned with the structure of large
scale fluctuations.


title: Modified p-modes in penumbral filaments?

abstract:
  Aims: The primary objective of this study is to search for and identify wave
modes within a sunspot penumbra.
  Methods: Infrared spectropolarimetric time series data are inverted using a
model comprising two atmospheric components in each spatial pixel. Fourier
phase difference analysis is performed on the line-of-sight velocities
retrieved from both components to determine time delays between the velocity
signals. In addition, the vertical separation between the signals in the two
components is calculated from the Stokes velocity response functions.
  Results: The inversion yields two atmospheric components, one permeated by a
nearly horizontal magnetic field, the other with a less-inclined magnetic
field. Time delays between the oscillations in the two components in the
frequency range 2.5-4.5 mHz are combined with speeds of atmospheric wave modes
to determine wave travel distances. These are compared to expected path lengths
obtained from response functions of the observed spectral lines in the
different atmospheric components. Fast-mode (i.e., modified p-mode) waves
exhibit the best agreement with the observations when propagating toward the
sunspot at an angle ~50 degrees to the vertical.


title: On The Local Well-Posedness for Some Systems of Coupled KdV Equations

abstract:
  Using the theory developed by Kenig, Ponce, and Vega, we prove that the
Hirota-Satsuma system is locally well-posed in Sobolev spaces $H^s(\mathbb{R})
\times H^{s}(\mathbb{R})$ for $3/4<s\le1$. We introduce some Bourgain-type
spaces $X_{s,b}^a$ for $a\not =0$, $s,b \in \mathbb{R}$ to obtain local
well-posedness for the Gear-Grimshaw system in $H^s(\mathbb{R})\times
H^s(\mathbb{R})$ for $s>-3/4$, by establishing new mixed-bilinear estimates
involving the two Bourgain-type spaces $X_{s,b}^{-\alpha_-}$ and
$X_{s,b}^{-\alpha_+}$ adapted to $\partial_t+\alpha_-\partial_x^3$ and
$\partial_t+\alpha_+\partial_x^3$ respectively, where
$|\alpha_+|=|\alpha_-|\not = 0$.


title: SN Shock Evolution in the Circumstellar Medium surrounding SN 1987A

abstract:
  We study the structure of the circumstellar medium surrounding SN 1987A in
the equatorial plane. Furthermore, we study the evolution of the SN shock
within this medium during the first 25 years, and the resulting hard X-ray and
radio emission from the remnant.


title:
A Note on Conserved Charges of Asymptotically Flat and Anti-de Sitter
  Spaces in Arbitrary Dimensions

abstract:
  The calculation of conserved charges of black holes is a rich problem, for
which many methods are known. Until recently, there was some controversy on the
proper definition of conserved charges in asymptotically anti-de Sitter (AdS)
spaces in arbitrary dimensions. This paper provides a systematic and explicit
Hamiltonian derivation of the energy and the angular momenta of both
asymptotically flat and asymptotically AdS spacetimes in any dimension D bigger
or equal to 4. This requires as a first step a precise determination of the
asymptotic conditions of the metric and of its conjugate momentum. These
conditions happen to be achieved in ellipsoidal coordinates adapted to the
rotating solutions.The asymptotic symmetry algebra is found to be isomorphic
either to the Poincare algebra or to the so(D-1, 2) algebra, as expected. In
the asymptotically flat case, the boundary conditions involve a generalization
of the parity conditions, introduced by Regge and Teitelboim, which are
necessary to make the angular momenta finite. The charges are explicitly
computed for Kerr and Kerr-AdS black holes for arbitrary D and they are shown
to be in agreement with thermodynamical arguments.


title:
A comparative study for the pair-creation contact process using series
  expansions

abstract:
  A comparative study between two distinct perturbative series expansions for
the pair-creation contact process is presented. In contrast to the ordinary
contact process, whose supercritical series expansions provide accurate
estimates for its critical behavior, the supercritical approach does not work
properly when applied to the pair-creation process. To circumvent this problem
a procedure is introduced in which one-site creation is added to the
pair-creation. An alternative method is the generation of subcritical series
expansions which works even for the case of the pure pair-creation process.
Differently from the supercritical case, the subcritical series yields
estimates that are compatible with numerical simulations.


title: Sampling using a `bank' of clues

abstract:
  An easy-to-implement form of the Metropolis Algorithm is described which,
unlike most standard techniques, is well suited to sampling from multi-modal
distributions on spaces with moderate numbers of dimensions (order ten) in
environments typical of investigations into current constraints on
Beyond-the-Standard-Model physics. The sampling technique makes use of
pre-existing information (which can safely be of low or uncertain quality)
relating to the distribution from which it is desired to sample. This
information should come in the form of a ``bank'' or ``cache'' of space points
of which at least some may be expected to be near regions of interest in the
desired distribution. In practical circumstances such ``banks of clues'' are
easy to assemble from earlier work, aborted runs, discarded burn-in samples
from failed sampling attempts, or from prior scouting investigations. The
technique equilibrates between disconnected parts of the distribution without
user input. The algorithm is not lead astray by ``bad'' clues, but there is no
free lunch: performance gains will only be seen where clues are helpful.


title: Natural Priors, CMSSM Fits and LHC Weather Forecasts

abstract:
  Previous LHC forecasts for the constrained minimal supersymmetric standard
model (CMSSM), based on current astrophysical and laboratory measurements, have
used priors that are flat in the parameter tan beta, while being constrained to
postdict the central experimental value of MZ. We construct a different, new
and more natural prior with a measure in mu and B (the more fundamental MSSM
parameters from which tan beta and MZ are actually derived). We find that as a
consequence this choice leads to a well defined fine-tuning measure in the
parameter space. We investigate the effect of such on global CMSSM fits to
indirect constraints, providing posterior probability distributions for Large
Hadron Collider (LHC) sparticle production cross sections. The change in priors
has a significant effect, strongly suppressing the pseudoscalar Higgs boson
dark matter annihilation region, and diminishing the probable values of
sparticle masses. We also show how to interpret fit information from a Markov
Chain Monte Carlo in a frequentist fashion; namely by using the profile
likelihood. Bayesian and frequentist interpretations of CMSSM fits are compared
and contrasted.


title: Adjoints of composition operators with rational symbol

abstract:
  Building on techniques developed by Cowen and Gallardo-Guti\'{e}rrez, we find
a concrete formula for the adjoint of a composition operator with rational
symbol acting on the Hardy space $H^{2}$. We consider some specific examples,
comparing our formula with several results that were previously known.


title: On the noncommutative standard model

abstract:
  We propose a pedestrian review of the noncommutative standard model in its
present state.


title: The Glassy Wormlike Chain

abstract:
  We introduce a new model for the dynamics of a wormlike chain in an
environment that gives rise to a rough free energy landscape, which we baptise
the glassy wormlike chain. It is obtained from the common wormlike chain by an
exponential stretching of the relaxation spectrum of its long-wavelength
eigenmodes, controlled by a single stretching parameter. Predictions for
pertinent observables such as the dynamic structure factor and the
microrheological susceptibility exhibit the characteristics of soft glassy
rheology and compare favourably with experimental data for reconstituted
cytoskeletal networks and live cells. We speculate about the possible
microscopic origin of the stretching, implications for the nonlinear rheology,
and the potential physiological significance of our results.


title:
On the blow-up threshold for weakly coupled nonlinear Schroedinger
  equations

abstract:
  We study the Cauchy problem for a system of two coupled nonlinear focusing
Schroedinger equations arising in nonlinear optics. We discuss when the
solutions are global in time or blow-up in finite time. Some results, in
dependence of the data of the problem, are proved; in particular we give a
bound, depending on the coupling parameter, for the blow-up threshold.


title: Colors Of Graphite On Silicon Dioxide

abstract:
  Monoatomic layers of graphite can be electrically contacted and used as
building blocks for new promising devices. These experiment are today possible
thanks to the fact that very thin graphite can be identified on a dielectric
substrate using a simple optical microscope. We investigate the mechanism
behind the strong visibility of graphite and we discuss the importance of the
substrate and of the microcope objective used for the imaging.


title:
How to Find More Supernovae with Less Work: Object Classification
  Techniques for Difference Imaging

abstract:
  We present the results of applying new object classification techniques to
difference images in the context of the Nearby Supernova Factory supernova
search. Most current supernova searches subtract reference images from new
images, identify objects in these difference images, and apply simple threshold
cuts on parameters such as statistical significance, shape, and motion to
reject objects such as cosmic rays, asteroids, and subtraction artifacts.
Although most static objects subtract cleanly, even a very low false positive
detection rate can lead to hundreds of non-supernova candidates which must be
vetted by human inspection before triggering additional followup. In comparison
to simple threshold cuts, more sophisticated methods such as Boosted Decision
Trees, Random Forests, and Support Vector Machines provide dramatically better
object discrimination. At the Nearby Supernova Factory, we reduced the number
of non-supernova candidates by a factor of 10 while increasing our supernova
identification efficiency. Methods such as these will be crucial for
maintaining a reasonable false positive rate in the automated transient alert
pipelines of upcoming projects such as PanSTARRS and LSST.


title:
Sgr A$^*$: a laboratory to measure the central black hole and cluster
  parameters

abstract:
  Several stars orbit around a black hole candidate of mass $3.7\times 10^6$
M$_{\odot}$, in the region of the Galactic Center (GC). Looking for General
Relativistic (GR) periastron shifts is limited by the existence of a stellar
cluster around the black hole that would modify the orbits due to classical
effects that might mask the GR effect. Only if one knows the cluster parameters
(its mass and core radius) it is possible to unequivocally deduce the GR
effects expected and then test them. In this paper it is shown that the
observation of the proper motion of Sgr A$^*$, $v_{Sgr A^*} = (0.4\pm 0.9)$ km
s$^{-1}$ (\citealt{reid2004}), could help us to constrain the cluster
parameters significantly and that future measurements of the periastron shifts
for at least three stars may adequately determine the cluster parameters and
the mass of the black hole.


title: Radio-frequency discharges in Oxygen. Part 1: Modeling

abstract:
  In this series of three papers we present results from a combined
experimental and theoretical effort to quantitatively describe capacitively
coupled radio-frequency discharges in oxygen. The particle-in-cell Monte-Carlo
model on which the theoretical description is based will be described in the
present paper. It treats space charge fields and transport processes on an
equal footing with the most important plasma-chemical reactions. For given
external voltage and pressure, the model determines the electric potential
within the discharge and the distribution functions for electrons, negatively
charged atomic oxygen, and positively charged molecular oxygen. Previously used
scattering and reaction cross section data are critically assessed and in some
cases modified. To validate our model, we compare the densities in the bulk of
the discharge with experimental data and find good agreement, indicating that
essential aspects of an oxygen discharge are captured.


title: On Instantons in Holographic QCD

abstract:
  We examine instantons and solitons of the effective action of probe D8-branes
in the background of $N_c$ D4-branes which has served as a holographic
description of QCD. We show that the 4d instantons sit at the minimum of the
Euclidean 5d action. Restricting to the static solitons of the five-dimensional
model we are led to consider monopoles in a 3-dimensional curved space. Since
the background metric depends only on the fifth coordinate, it is possible to
reduce the monopole equations to the ones in flat space and write down the
explicit solutions.


title: Particle-based modeling of oxygen discharges

abstract:
  We present an one-dimensional particle-in-cell Monte-Carlo model for
capacitively coupled radio-frequency discharges in oxygen. The model
quantitatively describes the central part of the discharge. For a given voltage
and pressure, it self-consistently determines the electric potential and the
distribution functions for electrons, negatively charged atomic oxygen, and
positively charged molecular oxygen. Previously used collision cross sections
are critically assessed and in some cases modified. Provided associative
detachment due to metastable oxygen molecules is included in the model, the
electro-negativities in the center of the discharge are in excellent agreement
with experiments. Due to lack of empirical data for the cross section of this
process, we propose a simple model and discuss its limitations.


title: Electron Doping of Cuprates via Interfaces with Manganites

abstract:
  The electron doping of undoped high-$T_c$ cuprates via the transfer of charge
from manganites (or other oxides) using heterostructure geometries is here
theoretically discussed. This possibility is mainly addressed via a detailed
analysis of photoemission and diffusion voltage experiments, which locate the
Fermi level of manganites above the bottom of the upper Hubbard band of some
cuprate parent compounds. A diagram with the relative location of Fermi levels
and gaps for several oxides is presented. The procedure discussed here is
generic, allowing for the qualitative prediction of the charge flow direction
at several oxide interfaces. The addition of electrons to antiferromagnetic Cu
oxides may lead to a superconducting state at the interface with minimal
quenched disorder. Model calculations using static and dynamical mean-field
theory, supplemented by a Poisson equation formalism to address charge
redistribution at the interface, support this view. The magnetic state of the
manganites could be antiferromagnetic or ferromagnetic. The former is better to
induce superconductivity than the latter, since the spin-polarized charge
transfer will be detrimental to singlet superconductivity. It is concluded that
in spite of the robust Hubbard gaps, the electron doping of undoped cuprates at
interfaces appears possible, and its realization may open an exciting area of
research in oxide heterostructures.


title:
Transmission measurement at 10.6 microns of Te2As3Se5 rib-waveguides on
  As2S3 substrate

abstract:
  The feasibility of chalcogenide rib waveguides working at lambda = 10.6
microns has been demonstrated. The waveguides comprised a several microns thick
Te2As3Se5 film deposited by thermal evaporation on a polished As2S3 glass
substrate and further etched by physical etching in Ar or CF4/O2 atmosphere.
Output images at 10.6 microns and some propagation losses roughly estimated at
10dB/cm proved that the obtained structures behaved as channel waveguides with
a good lateral confinement of the light. The work opens the doors to the
realisation of components able to work in the mid and thermal infrared up to 20
microns and even more.


title: The Extended Bloch Group and the Cheeger-Chern-Simons Class

abstract:
  We present a formula for the full Cheeger-Chern-Simons class of the
tautological flat complex vector bundle of rank two over BSL(2,\C^\delta). Our
formula improves the formula by Dupont and Zickert, where the class is only
computed modulo 2-torsion.


title: Survival of a diffusing particle in an expanding cage

abstract:
  We consider a Brownian particle, with diffusion constant D, moving inside an
expanding d-dimensional sphere whose surface is an absorbing boundary for the
particle. The sphere has initial radius L_0 and expands at a constant rate c.
We calculate the joint probability density, p(r,t|r_0), that the particle
survives until time t, and is at a distance r from the centre of the sphere,
given that it started at a distance r_0 from the centre.


title: Slow cross-symmetry phase relaxation in complex collisions

abstract:
  We discuss the effect of slow phase relaxation and the spin off-diagonal
$S$-matrix correlations on the cross section energy oscillations and the time
evolution of the highly excited intermediate systems formed in complex
collisions. Such deformed intermediate complexes with strongly overlapping
resonances can be formed in heavy ion collisions, bimolecular chemical
reactions and atomic cluster collisions. The effects of quasiperiodic energy
dependence of the cross sections, coherent rotation of the hyperdeformed
$\simeq (3:1)$ intermediate complex, Schr\"odinger cat states and
quantum-classical transition are studied for $^{24}$Mg+$^{28}$Si heavy ion
scattering.


title:
Change point estimation for the telegraph process observed at discrete
  times

abstract:
  The telegraph process models a random motion with finite velocity and it is
usually proposed as an alternative to diffusion models. The process describes
the position of a particle moving on the real line, alternatively with constant
velocity $+ v$ or $-v$. The changes of direction are governed by an homogeneous
Poisson process with rate $\lambda >0.$ In this paper, we consider a change
point estimation problem for the rate of the underlying Poisson process by
means of least squares method. The consistency and the rate of convergence for
the change point estimator are obtained and its asymptotic distribution is
derived. Applications to real data are also presented.

categories: math.ST math.PR q-fin.ST stat.ME stat.TH


title: Rothberger's property in finite powers

abstract:
  We show that several classical Ramseyan statements, and a forcing statement,
are each equivalent to having Rothberger's property in all finite powers.


title: Non Supersymmetric Metastable Vacua in N=2 SYM Softly Broken to N=1

abstract:
  We find non-supersymmetric metastable vacua in four dimensional N=2 gauge
theories softly broken to N=1 by a superpotential term. First we study the
simplest case, namely the SU(2) gauge theory without flavors. We study the
spectrum and lifetime of the metastable vacuum and possible embeddings of the
model in UV complete theories. Then we consider larger gauge group theories
with flavors. We show that when we softly break them to N=1, the potential
induced on specific submanifolds of their moduli space is identical to the
potential in lower rank gauge theories. Then we show that the potential
increases when we move away from this submanifold, allowing us to construct
metastable vacua on them in the theories that can be reduced to the SU(2) case.


title: Space-time percolation

abstract:
  The contact model for the spread of disease may be viewed as a directed
percolation model on $\ZZ \times \RR$ in which the continuum axis is oriented
in the direction of increasing time. Techniques from percolation have enabled a
fairly complete analysis of the contact model at and near its critical point.
The corresponding process when the time-axis is unoriented is an undirected
percolation model to which now standard techniques may be applied. One may
construct in similar vein a random-cluster model on $\ZZ \times \RR$, with
associated continuum Ising and Potts models. These models are of independent
interest, in addition to providing a path-integral representation of the
quantum Ising model with transverse field. This representation may be used to
obtain a bound on the entanglement of a finite set of spins in the quantum
Ising model on $\ZZ$, where this entanglement is measured via the entropy of
the reduced density matrix. The mean-field version of the quantum Ising model
gives rise to a random-cluster model on $K_n \times \RR$, thereby extending the
Erdos-Renyi random graph on the complete graph $K_n$.


title: Strong Stein neighborhood bases

abstract:
  Let D be a smooth bounded pseudoconvex domain in C^n. We give several
characterizations for the closure of D to have a strong Stein neighborhood
basis in the sense that D has a defining function r such that {z\in C^n:r(z)<a}
is pseudoconvex for sufficiently small a>0. We also show that this condition is
invariant under proper holomorphic maps that extend smoothly to the boundary.


title:
Effective attraction induced by repulsive interaction in a spin-transfer
  system

abstract:
  In magnetic systems with dominating easy-plane anisotropy the magnetization
can be described by an effective one dimensional equation for the in-plane
angle. Re-deriving this equation in the presence of spin-transfer torques, we
obtain a description that allows for a more intuitive understanding of
spintronic devices' operation and can serve as a tool for finding new dynamic
regimes. A surprising prediction is obtained for a planar ``spin-flip
transistor'': an unstable equilibrium point can be stabilized by a current
induced torque that further repels the system from that point. Stabilization by
repulsion happens due to the presence of dissipative environment and requires a
Gilbert damping constant that is large enough to ensure overdamped dynamics at
zero current.


title:
Thermalized non-equilibrated matter and high temperature superconducting
  state in quantum many-body systems

abstract:
  A characteristic feature of thermalized non-equilibrated matter is that, in
spite of energy relaxation--equilibration, a phase memory of the way the
many-body system was excited remains. As an example, we analyze data on a
strong forward peaking of thermal proton yield in the Bi($\gamma$,p)
photonuclear reaction. New analysis shows that the phase relaxation in
highly-excited heavy nuclei can be 8 orders of magnitude or even much longer
than the energy relaxation. We argue that thermalized non-equilibrated matter
resembles a high temperature superconducting state in quantum many-body
systems. We briefly present results on the time-dependent correlation function
of the many-particle density fluctuations for such a superconducting state. It
should be of interest to experimentally search for manifestations of
thermalized non-equilibrated matter in many-body mesoscopic systems and
nanostructures.


title: Geometry of the Pfaff lattices

abstract:
  Pfaff lattice was introduced by Adler and van Moerbeke to describe the
partition functions for the random matrix models of GOE and GSE type. The
partition functions of those matrix models are given by the Pfaffians of
certain skew-symmetric matrices called the moment matrices, and they are the
$\tau$-functions of the Pfaff lattice. In this paper, we study a finite version
of the Pfaff lattice equation as a Hamiltonian system. In particular, we prove
the complete integrability in the sense of Arnold-Liouville, and using a moment
map, we describe the real isospectral varieties of the Pfaff lattice. The image
of the moment map is a convex polytope whose vertices are identified as the
fixed points of the flow generated by the Pfaff lattice.


title:
Vibration-Induced Conductivity Fluctuation Measurement for Soil Bulk
  Density Analysis

abstract:
  Soil bulk density affects water storage, water and nutrient movement, and
plant root activity in the soil profile. Its measurement is difficult in field
conditions. Vibration-induced conductivity fluctuation was investigated to
quantify soil bulk density with possible field applications in the future. The
AC electrical conductivity of soil was measured using a pair of blade-like
electrodes while exposing the soil to periodic vibration. The blades were
positioned longitudinally and transversally to the direction of the induced
vibration to enable the calculation of a normalized index. The normalized index
was expected to provide data independent from the vibration strength and to
reduce the effect of soil salinity and water content. The experiment was
conducted on natural and salinized fine sand at two moisture conditions and
four bulk densities. The blade-shaped electrodes improved electrode-soil
contact compared to cylindrical electrodes, and thereby, reduced measurement
noise. Simulations on a simplified resistor lattice indicate that the
transversal effect increases as soil bulk density decreases. Measurement of dry
sand showed a negative correlation between the normalized conductivity
fluctuation and soil bulk density for both longitudinal and transversal
settings. The decrease in the transversal signal was smaller than expected. The
wet natural and salinized soils performed very similarly as hypothesized, but
their normalized VICOF response was not significant to bulk density changes.


title: Optically Thick Radio Cores of Narrow-Waist Bipolar Nebulae

abstract:
  We report our search for optically thick radio cores in sixteen narrow-waist
bipolar nebulae. Optically thick cores are a characteristic signature of
collimated ionized winds. Eleven northern nebulae were observed with the Very
Large Array (VLA) at 1.3 cm and 0.7 cm, and five southern nebulae were observed
with the Australia Telescope Compact Array (ATCA) at 6 cm and 3.6 cm. Two
northern objects, 19W32 and M 1-91, and three southern objects, He 2-25, He
2-84 and Mz 3, were found to exhibit a compact radio core with a rising
spectrum consistent with an ionized jet. Such jets have been seen in M 2-9 and
may be responsible for shaping bipolar structure in planetary nebulae.


title:
Murphy et al. Reply to the Comment by Kopeikin on "Gravitomagnetic
  Influence on Gyroscopes and on the Lunar Orbit"

abstract:
  Lunar laser ranging analysis, as regularly performed in the solar system
barycentric frame, requires the presence of the gravitomagnetic term in the
equation of motion at the strength predicted by general relativity. The same
term is responsible for the Lense Thirring effect. Any attempt to modify the
strength of the gravitomagnetic interaction would have to do so in a way that
does not destroy the fit to lunar ranging data and other observations.


title:
Space-time resolved electrokinetics in cylindrical and semi-cylindrical
  microchannels

abstract:
  It is shown show how to employ Bessel-Fourier series in order to obtain a
complete space-time resolved description of electrokinetic phenomena in
cylindrical and semi-cylindrical microfluidic channels.


title: Fast quantum key distribution with decoy number states

abstract:
  We investigate the use of photon number states to identify eavesdropping
attacks on quantum key distribution (QKD) schemes. The technique is based on
the fact that different photon numbers traverse a channel with different
transmittivity. We then describe two QKD schemes that utilize this method, one
of which overcomes the upper limit on the key generation rate imposed by the
dead time of detectors when using a heralded source of photons.


title: Hodge Spaces for Real Toric Varieties

abstract:
  We define the Z/2Z Hodge spaces H_{pq}(\Sigma) of a fan \Sigma.
  If \Sigma is the normal fan of a reflexive polytope \Delta then we use
polyhedral duality to compute the Z/2Z Hodge Spaces of \Sigma. In particular,
if the cones of dimension at most e in the face fan \Sigma^* of \Delta are
smooth then we compute H_{pq}(\Sigma) for p<e-1. If \Sigma^* is a smooth fan
then we completely determine the spaces H_{pq}(\Sigma) and we show the toric
variety X associated to \Sigma is maximal, meaning that the sum of the Z/2Z
Betti numbers of X(R) is equal to the sum of the Z/2Z Betti numbers of X(C).


title: Superconductivity in epitaxial thin films of NaxCoO2 y D2O

abstract:
  The observation of superconductivity in the layered transition metal oxide
NaxCoO2 y H2O (K. Takada et al., Nature 422, 53 (2003)) has caused a tremendous
upsurge of scientific interest due to its similarities and its differences to
the copper based high-temperature superconductors. Two years after the
discovery, we report the fabrication of single-phase superconducting epitaxial
thin films of Na0.3CoO2 x 1.3 D2O grown by pulsed laser deposition technique.
This opens additional roads for experimental research exploring the
superconducting state and the phase diagram of this unconventional material.


title: Leonard triples and hypercubes

abstract:
  Let $V$ denote a vector space over C with finite positive dimension. By a
{\em Leonard triple} on $V$ we mean an ordered triple of linear operators on
$V$ such that for each of these operators there exists a basis of $V$ with
respect to which the matrix representing that operator is diagonal and the
matrices representing the other two operators are irreducible tridiagonal. Let
$D$ denote a positive integer and let $Q_D$ denote the graph of the
$D$-dimensional hypercube. Let $X$ denote the vertex set of $Q_D$ and let $A$
denote the adjacency matrix of $Q_D$. Fix $x \in X$ and let $A^*$ denote the
corresponding dual adjacency matrix. Let $T$ denote the subalgebra of
$Mat_X(C)$ generated by $A, A^*$. We refer to $T$ as the {\em Terwilliger
algebra of} $Q_D$ {\em with respect to} $x$. The matrices $A$ and $A^*$ are
related by the fact that $2 \im A = A^* A^e - A^e A^*$ and $2 \im A^* = A^e A -
A A^e$, where $2 \im A^e = A A^* - A^* A$ and $\im^2=-1$. We show that the
triple $A$, $A^*$, $A^e$ acts on each irreducible $T$-module as a Leonard
triple. We give a detailed description of these Leonard triples.


title: Bringing errors into focus

abstract:
  This lecture presents recent advances in the theory of errors propagation. We
first explain in which cases the propagation of errors may be performed with a
first order differential calculus or needs a second order differential
calculus. Then we point out the link between error propagation and the concept
of second order vector in differential geometry, emphasizing the existence of a
slight ambiguity concerning the bias operator. The third part in devoted to the
powerful framework of Dirichlet forms whose main feature is to apply easily to
infinite dimensional models including the Wiener space (giving an
interpretation of Malliavin calculus in terms of errors), the Poisson space and
the Monte Carlo space. In the fourth part we show how an error in the usual
mathematical sense, i.e. an approximate quantity, may yield a Dirichlet form
and we introduce the four bias operators. Eventually we connect the Dirichlet
form with statistics by identifying the square of field operator with the
inverse of the Fisher information matrix.


title:
Bijectiveness of the Nash Map for Quasi-Ordinary Hypersurface
  Singularities

abstract:
  In this paper we give a positive answer to a question of Nash concerning the
arc space of a singularity, for the class of quasi-ordinary hypersurface
singularities, extending to this case previous results and techniques of
Shihoko Ishii.


title: Dark matter and the first stars: a new phase of stellar evolution

abstract:
  A mechanism is identified whereby dark matter (DM) in protostellar halos
dramatically alters the current theoretical framework for the formation of the
first stars. Heat from neutralino DM annihilation is shown to overwhelm any
cooling mechanism, consequently impeding the star formation process and
possibly leading to a new stellar phase. A "dark star'' may result: a giant
($\gtrsim 1$ AU) hydrogen-helium star powered by DM annihilation instead of
nuclear fusion. Observational consequences are discussed.


title: Orthogonality catastrophe and Kondo effect in graphene

abstract:
  Anderson's orthogonality catastrophe in graphene, at energies close to the
Dirac point, is analyzed. It is shown that, in clean systems, the orthogonality
catastrophe is suppressed, due to the vanishing density of states at the Dirac
point. In the presence of preexisting localized states at the Dirac energy, the
orthogonality catastrophe shows similar features to those found in normal
metals with a finite density of states at the Fermi level. The implications for
the Kondo effect induced by magnetic impurities, and for the Fermi edge
singularities in tunneling processes are also discussed.


title: Quantum spin correlations in an organometallic alternating sign chain

abstract:
  High resolution inelastic neutron scattering is used to study excitations in
the organometallic magnet DMACuCl$_3$. The correct magnetic Hamiltonian
describing this material has been debated for many years. Combined with high
field bulk magnetization and susceptibility studies, the new results imply that
DMACuCl$_3$ is a realization of the $S=1/2$ alternating
antiferromagnetic-ferromagnetic (AFM-FM) chain. Coupled-cluster calculations
are used to derive exchange parameters, showing that the AFM and FM
interactions have nearly the same strength. Analysis of the scattering
intensities shows clear evidence for inter-dimer spin correlations, in contrast
to existing results for conventional alternating chains. The results are
discussed in the context of recent ideas concerning quantum entanglement.


title: Birationality of \'etale morphisms via surgery

abstract:
  We use a counting argument and surgery theory to show that if $D$ is a
sufficiently general algebraic hypersurface in $\Bbb C^n$, then any local
diffeomorphism $F:X \to \Bbb C^n$ of simply connected manifolds which is a
$d$-sheeted cover away from $D$ has degree $d=1$ or $d=\infty$ (however all
degrees $d > 1$ are possible if $F$ fails to be a local diffeomorphism at even
a single point). In particular, any \'etale morphism $F:X \to \Bbb C^n$ of
algebraic varieties which covers away from such a hypersurface $D$ must be
birational.


title: Black Hole Accretion in Low States: Electron Heating

abstract:
  Plasmas in an accretion flow are heated by MHD turbulence generated through
the magneto-rotational instability. The viscous stress driving the accretion is
intimately connected to the microscopic processes of turbulence dissipation. We
show that, in a few well-observed black hole accretion systems, there is
compelling observational evidence of efficient electron heating by turbulence
or collective plasma effects in low accretion states, when Coulomb collisions
are not efficient enough to establish a thermal equilibrium between electrons
and ions at small radii. However, charged particles reach a thermal equilibrium
with their kind much faster than with others through Coulomb collisions, a
two-temperature accretion flow is expected. We consider a Keplerian accretion
flow with a constant mass accretion rate in the pseudo-Newtonian gravitational
potential and take into account the bremsstrahlung, synchrotron, and inverse
Comptonization cooling processes. The critical mass accretion rate, below which
the two-temperature solution may exist, is determined by the cooling processes
and the collisional energy exchanges between electrons and ions and has very
weak dependence on the collision-less heating of electrons by turbulence, which
becomes more important at lower accretion rates. Collision-less heating of
electrons by MHD turbulence can no longer be ignored in quantitative
investigations of these systems.


title: Measuring Bremsstrahlung Photons in 200 GeV p+p Collisions

abstract:
  Direct photon production is an important observable in heavy ion collisions
as photons are penetrating and therefore largely insensetive to final state
effects that lead to jet quenching. Measurements of the fragmentation component
to prompt photon yields in p+p and Au+Au collisions will provide both an
important test of pQCD predictions and of predictions for modifications of this
component in heavy ion collisions. By selecting photons associated with jets on
the near side using hadron-photon correlations, fragmentation photons can be
measured directly.


title: Tuning the conductance of a molecular switch

abstract:
  The ability to control the conductance of single molecules will have a major
impact in nanoscale electronics. Azobenzene, a molecule that changes
conformation as a result of a trans/cis transition when exposed to radiation,
could form the basis of a light-driven molecular switch. It is therefore
crucial to clarify the electrical transport characteristics of this molecule.
Here, we investigate theoretically charge transport in a system in which a
single azobenzene molecule is attached to two carbon nanotubes. In clear
contrast to gold electrodes, the nanotubes can act as true nanoscale electrodes
and we show that the low-energy conduction properties of the junction may be
dramatically modified by changing the topology of the contacts between the
nanotubes and the molecules, and/or the chirality of the nanotubes (that is,
zigzag or armchair). We propose experiments to demonstrate controlled
electrical switching with nanotube electrodes.


title: Subrings of the asymptotic Hecke algebra of type $H_4$

abstract:
  The structure of subring $J^{\Gamma \cap \Gamma^{-1}}$ of the asymptotic
Hecke algebra is described for $\Gamma$ a left cell of the Coxeter group of
type $H_4$. A small set of generators is produced. The subalgebras spanned by a
subset of the basis ${t_x}_{x\in \Gamma\cap\Gamma^{-1}}$ are determined.


title:
Itinerant and localized magnetism on the triangular lattice: sodium rich
  phases of Na$_x$CoO$_2$

abstract:
  We study the interplay between correlation, itinerant ferromagnetism and
local moment formation on the electron doped triangular lattice of sodium
cobaltates Na$_x$CoO$_2$. We find that strong correlation renormalizes the
Stoner criterion and stabilizes the paramagnetic state for $x<x_c\simeq0.67$.
For $x>x_c$, ferromagnetic (FM) order emerges. The enhanced Na dopant potential
fluctuations play a crucial role in the sodium rich phases and lead to an
inhomogeneous FM state, exhibiting nonmagnetic Co$^{3+}$ patches,
antiferromagnetic (AF) correlated regions, and FM clusters with AF domains.
Hole doping the band insulator at x=1 leads to the formation of local moments
near the Na vacancies and AF correlated magnetic clusters. We explain recent
observations by neutron, $\mu$SR, and NMR experiments on the evolution of the
magnetic properties in the sodium rich phases.


title:
Dependence of the Local Reionization History on Halo Mass and
  Environment: Did Virgo Reionize the Local Group?

abstract:
  The reionization of the Universe has profound effects on the way galaxies
form and on their observed properties at later times. Of particular importance
is the relative timing of the reionization history of a region and its halo
assembly history, which can affect the nature of the first stars formed in that
region, the properties and radial distribution of its stellar halo, globular
cluster population and its satellite galaxies. We distinguish two basic cases
for the reionization of a halo - internal reionization, whereby the stars
forming in situ reionize their host galaxy, and external reionization, whereby
the progenitor of a galaxy is reionized by external radiation before its own
stars are able to form in sufficient numbers. We use a set of large-scale
radiative transfer and structure formation simulations, based on cosmologies
derived from both WMAP 1-year and WMAP 3-year data, to evaluate the mean
reionization redshifts and the probability of internal/external reionization
for Local Group-like systems, galaxies in the field and central cD galaxies in
clusters. We find that these probabilities are strongly dependent on the
underlying cosmology and the efficiency of photon production, but also on the
halo mass. There is a rapid transition between predominantly external and
predominantly internal reionization at a mass scale of 1.0e12 Msun
(corresponding roughly to L*galaxies), with haloes less massive than this being
reionized preferentially from distant sources. We provide a fit for the
reionization redshift as a function of halo mass, which could be helpful to
parameterize reionization in semi-analytical models of galaxy formation on
cosmological scales. We find no statistical correlation between the
reionization history of field galaxies and their environment.


title:
The Beta-Model Problem: The Incompatibility of X-ray and
  Sunyaev-Zeldovich Effect Model Fitting for Galaxy Clusters

abstract:
  We have analyzed a large sample of numerically simulated clusters to
demonstrate the adverse effects resulting from use of X-ray fitted beta-model
parameters with Sunyaev-Zeldovich effect (SZE) data. There is a fundamental
incompatibility between model fits to X-ray surface brightness profiles and
those done with SZE profiles. Since observational SZE radial profiles are in
short supply, the X-ray parameters are often used in SZE analysis. We show that
this leads to biased estimates of the integrated Compton y-parameter inside
r_{500} calculated from clusters. We suggest a simple correction of the method,
using a non-isothermal beta-model modified by a universal temperature profile,
which brings these calculated quantities into closer agreement with the true
values.


title: Transport in disordered graphene nanoribbons

abstract:
  We study electronic transport in graphene nanoribbons with rough edges. We
first consider a model of weak disorder that corresponds to an armchair ribbon
whose width randomly changes by a single unit cell size. We find that in this
case, the low-temperature conductivity is governed by an effective
one-dimensional hopping between segments of distinct band structure. We then
provide numerical evidence and qualitative arguments that similar behavior also
occurs in the limit of strong uncorrelated boundary disorder.


title:
A combined analysis of 3D Weak Lensing, Lyman-alpha forest and WMAP year
  three data

abstract:
  We present constraints on the amplitude and shape of the matter power
spectrum and the density of dark matter within the framework of a standard
LambdaCDM model. We use a Markov Chain Monte Carlo approach to combine
independent measurements of the three dimensional weak gravitational lensing
shear field by the COSMOS survey, of low and high resolution Ly-alpha forest
flux power spectrum by SDSS and LUQAS, and of Cosmic Microwave Background
temperature and polarization anisotropies by WMAP. We note good agreement
between the amplitude of the matter power spectrum on intermediate and small
scales as inferred from Ly-alpha forest and lensing data. The Ly-alpha forest
data helps to break the sigma_8-Omega_m degeneracy characteristic of weak
lensing results, yielding sigma_8 = 0.876 +- 0.048 for COSMOS plus Ly-alpha
SDSS data. This is somewhat larger than the value preferred by the WMAP year
three CMB data. Combining all three data sets significantly tightens the
constraints on sigma_8, the spectral index of primordial density fluctuation
n_s, a possible running of the spectral index n_run and the matter density
Omega_m. Assuming no running, the joint constraints for COSMOS, SDSS and WMAP
are sigma_8 = 0.800 +- 0.023, n_s = 0.971 +- 0.011, Omega_m = 0.247 +- 0.016
(1-sigma error bars).


title: An Eta Primer: Solving the U(1) Problem with AdS/QCD

abstract:
  Inspired by the AdS/CFT correspondence, we study the pseudoscalar mesons of
QCD through a dual embedding in a strongly curved extra dimensional spacetime.
This model incorporates the consequences of symmetry and has very few free
parameters, due to constraints from five-dimensions and the operator product
expansion of QCD. Using as inputs the pion, kaon, and rho masses and fpi, we
compute the eta and eta prime masses to be 520 and 867 MeV, respectively. Their
decay rates into photons are also computed and found to be in good agreement
with data.


title: Do Killing-Yano tensors form a Lie Algebra?

abstract:
  Killing-Yano tensors are natural generalizations of Killing vectors. We
investigate whether Killing-Yano tensors form a graded Lie algebra with respect
to the Schouten-Nijenhuis bracket. We find that this proposition does not hold
in general, but that it does hold for constant curvature spacetimes. We also
show that Minkowski and (anti)-deSitter spacetimes have the maximal number of
Killing-Yano tensors of each rank and that the algebras of these tensors under
the SN bracket are relatively simple extensions of the Poincare and (A)dS
symmetry algebras.


title:
Molecular Line Emission from Massive Protostellar Disks: Predictions for
  ALMA and the EVLA

abstract:
  We compute the molecular line emission of massive protostellar disks by
solving the equation of radiative transfer through the cores and disks produced
by the recent radiation-hydrodynamic simulations of Krumholz, Klein, & McKee.
We find that in several representative lines the disks show brightness
temperatures of hundreds of Kelvin over velocity channels ~10 km s^-1 wide,
extending over regions hundreds of AU in size. We process the computed
intensities to model the performance of next-generation radio and submillimeter
telescopes. Our calculations show that observations using facilities such as
the EVLA and ALMA should be able to detect massive protostellar disks and
measure their rotation curves, at least in the nearest massive star-forming
regions. They should also detect significant sub-structure and non-axisymmetry
in the disks, and in some cases may be able to detect star-disk velocity
offsets of a few km s^-1, both of which are the result of strong gravitational
instability in massive disks. We use our simulations to explore the strengths
and weaknesses of different observational techniques, and we also discuss how
observations of massive protostellar disks may be used to distinguish between
alternative models of massive star formation.


title: Terahertz Room-Temperature Photonic Crystal Nanocavity Laser

abstract:
  We describe an efficient surface-passivated photonic crystal nanocavity
laser, demonstrating room-temperature operation with 3-ps total pulse duration
(detector response limited) and low-temperature operation with
ultra-low-threshold near 9uW.


title:
Radio Through X-ray Spectral Energy Distributions of 38 Broad Absorption
  Line Quasars

abstract:
  We have compiled the largest sample of multiwavelength spectral energy
distributions (SEDs) of Broad Absorption Line (BAL) quasars to date, from the
radio to the X-ray. We present new Spitzer MIPS (24, 70, and 160 micron)
observations of 38 BAL quasars in addition to data from the literature and
public archives. In general, the mid-infrared properties of BAL quasars are
consistent with those of non-BAL quasars of comparable luminosity. In
particular, the optical-to-mid-infrared luminosity ratios of the two
populations are indistinguishable. We also measure or place upper limits on the
contribution of star formation to the far-infrared power. Of 22 (57%) upper
limits, seven quasars have sufficiently sensitive constraints to conclude that
star formation likely contributes little (<20%) to their far-infrared power.
The 17 BAL quasars (45%) with detected excess far-infrared emission likely host
hyperluminous starbursts with L_fir,SF=10^{13-14} L_sun. Mid-infrared through
X-ray composite BAL quasar SEDs are presented, incorporating all of the
available photometry. Overall, we find no compelling evidence for inherent
differences between the SEDs of BAL vs. non-BAL quasars of comparable
luminosity. Therefore a ``cocoon'' picture of a typical BAL quasar outflow
whereby the wind covers a large fraction of the sky is not supported by the
mid-infrared SED comparison with normal quasars, and the disk-wind paradigm
with a typical radio-quiet quasar hosting a BAL region remains viable.


title: Displacement energy of coisotropic submanifolds and Hofer's geometry

abstract:
  We prove that the displacement energy of a stable coisotropic submanifold is
bounded away from zero if the ambient symplectic manifold is closed, rational
and satisfies a mild topological condition.


title:
Relativistic X-ray Lines from the Inner Accretion Disks Around Black
  Holes

abstract:
  Relativistic X-ray emission lines from the inner accretion disk around black
holes are reviewed. Recent observations with the Chandra X-ray Observatory,
X-ray Multi-Mirror Mission-Newton, and Suzaku are revealing these lines to be
good probes of strong gravitational effects. A number of important
observational and theoretical developments are highlighted, including evidence
of black hole spin and effects such as gravitational light bending, the
detection of relativistic lines in stellar-mass black holes, and evidence of
orbital-timescale line flux variability. In addition, the robustness of the
relativistic disk lines against absorption, scattering, and continuum effects
is discussed. Finally, prospects for improved measures of black hole spin and
understanding the spin history of supermassive black holes in the context of
black hole-galaxy co-evolution are presented. The best data and most rigorous
results strongly suggest that relativistic X-ray disk lines can drive future
explorations of General Relativity and disk physics.


title: Fundamental Parameters of He-Weak and He-Strong Stars

abstract:
  We carried out low resolution spectroscopic observations in the wavelength
range 3400-4700 A of 20 He-weak and 8 He-strong stars to determine their
fundamental parameters by means of the Divan-Chalonge-Barbier (BCD)
spectrophotometric system. For a few He-weak stars we also estimate the
effective temperatures and the angular diameters by integrating absolute fluxes
observed over a wide spectral range. Non-LTE model calculations are carried out
to study the influence of the He/H abundance ratio on the emergent radiation of
He-strong stars and on their Teff determination. We find that the effective
temperatures, surface gravities and bolometric absolute magnitudes of He-weak
stars estimated with the BCD system and the integrated flux method are in good
agreement between each other, and they also agree with previous determinations
based on several different methods. The mean discrepancy between the visual
absolute magnitudes derived using the Hipparcos parallaxes and the BCD values
is on average 0.3 mag for He-weak stars, while it is 0.5 mag for He-strong
stars. For He-strong stars, we note that the BCD calibration, based on stars in
the solar environment, leads to overestimated values of Teff. By means of model
atmosphere calculations with enhanced He/H abundance ratios we show that larger
He/H ratios produce smaller BD which naturally explains the Teff
overestimation. We take advantage of these calculations to introduce a method
to estimate the He/H abundance ratio in He-strong stars. The BD of HD 37479
suggests that the Teff of this star remains fairly constant as the star
spectrum undergoes changes in the intensity of H and He absorption lines. Data
for the He-strong star HD 66765 are reported for the first time.


title: Quark mass uncertainties revive KSVZ axion dark matter

abstract:
  The Kaplan-Manohar ambiguity in light quark masses allows for a larger
uncertainty in the ratio of up to down quark masses than naive estimates from
the chiral Lagrangian would indicate. We show that it allows for a relaxation
of experimental bounds on the QCD axion, specifically KSVZ axions in the $2-3
\mu$eV mass range composing 100% of the galactic dark matter halo can evade the
experimental limits placed by the ADMX collaboration.


title: The Design of Efficiently-Encodable Rate-Compatible LDPC Codes

abstract:
  We present a new class of irregular low-density parity-check (LDPC) codes for
moderate block lengths (up to a few thousand bits) that are well-suited for
rate-compatible puncturing. The proposed codes show good performance under
puncturing over a wide range of rates and are suitable for usage in incremental
redundancy hybrid-automatic repeat request (ARQ) systems. In addition, these
codes are linear-time encodable with simple shift-register circuits. For a
block length of 1200 bits the codes outperform optimized irregular LDPC codes
and extended irregular repeat-accumulate (eIRA) codes for all puncturing rates
0.6~0.9 (base code performance is almost the same) and are particularly good at
high puncturing rates where good puncturing performance has been previously
difficult to achieve.


title: Modeling Repulsive Gravity with Creation

abstract:
  There is a growing interest in the cosmologists for theories with negative
energy scalar fields and creation, in order to model a repulsive gravity. The
classical steady state cosmology proposed by Bondi, Gold and Hoyle in 1948, was
the first such theory which used a negative kinetic energy creation field to
invoke creation of matter. We emphasize that creation plays very crucial role
in cosmology and provides a natural explanation to the various explosive
phenomena occurring in local (z<0.1) and extra galactic universe. We exemplify
this point of view by considering the resurrected version of this theory - the
quasi-steady state theory, which tries to relate creation events directly to
the large scale dynamics of the universe and supplies more natural explanations
of the observed phenomena. Although the theory predicts a decelerating universe
at the present era, it explains successfully the recent SNe Ia observations
(which require an accelerating universe in the standard cosmology), as we show
in this paper by performing a Bayesian analysis of the data.


title:
On Verlinde-Like Formulas in c_{p,1} Logarithmic Conformal Field
  Theories

abstract:
  Two different approaches to calculate the fusion rules of the c_{p,1} series
of logarithmic conformal field theories are discussed. Both are based on the
modular transformation properties of a basis of chiral vacuum torus amplitudes,
which contains the characters of the irreducible representations. One of these
is an extension, which we develop here for a non-semisimple generalisation of
the Verlinde formula introduced by Fuchs et al., to include fusion products
with indecomposable representations. The other uses the Verlinde formula in its
usual form and gets the fusion coefficients in the limit, in which the basis of
torus amplitudes degenerates to the linear dependent set of characters of
irreducible and indecomposable representations. We discuss the effects, which
this linear dependence has on any result for fusion rules, which are calculated
from these character's modular transformation properties. We show that the two
presented methods are equivalent. Furthermore we calculate explicit BPZ-like
expressions for the resulting fusion rules for all p larger than 2.


title:
Strichartz and Smoothing Estimates for Schr\"odinger Operators with
  Almost Critical Magnetic Potentials in Three and Higher Dimensions

abstract:
  In this paper we consider magnetic Schr\"odinger operators in R^n, n \ge 3.
Under almost optimal conditions on the potentials in terms of decay and
regularity we prove smoothing and Strichartz estimates, as well as a limiting
absorption principle. For large gradient perturbations the latter is not a
corollary of the free case as the differentiated free resolvent does not have
small operator norm on any weighted L^2 spaces.
  We instead show that the spectral radius of such operators decreases to zero,
hence their perturbation of the identity is still invertible. The key estimates
are based on an angular decomposition of the free resolvent, or rather a bound
that holds uniformly for all possible angular decompositions. The proof avoids
the Fourier transform and instead uses H\"ormander's variable coefficient
Plancherel theorem for oscillatory integrals.


title:
The Solar-Interior Equation of State with the Path-Integral Formalism I.
  Domain of Validity

abstract:
  This is the first paper in a series that deals with solar-physics
applications of the equation-of-state formalism based on the formulation of the
so-called "Feynman-Kac (FK) representation". Here, the FK equation of state is
presented and adapted for solar applications. Its domain of validity is
assessed. The practical application to the Sun will be dealt with in Paper II.
Paper III will extend the current FK formalism to a higher order. Use of the FK
equation of state is limited to physical conditions for which more than 90% of
helium is ionized. This incudes the inner region of the Sun out to about .98 of
the solar radius. Despite this limitation, in the parts of the Sun where it is
applicable, the FK equation of state has the power to be more accurate than the
equations of state currently used in solar modeling. The FK approach is
especially suited to study physical effects such as Coulomb screening, bound
states, the onset of recombination of fully ionized species, as well as
diffraction and exchange effects. The localizing power of helioseismology
allows a test of the FK equation of state. Such a test will be beneficial both
for better solar models and for tighter solar constraints of the equation of
state.


title: Modified Brans-Dicke theory of gravity from five-dimensional vacuum

abstract:
  We investigate, in the context of five-dimensional (5D) Brans-Dicke theory of
gravity, the idea that macroscopic matter configurations can be generated from
pure vacuum in five dimensions, an approach first proposed in the framework of
general relativity. We show that the 5D Brans-Dicke vacuum equations when
reduced to four dimensions lead to a modified version of Brans-Dicke theory in
four dimensions (4D). As an application of the formalism, we obtain two
five-dimensional extensions of four-dimensional O'Hanlon and Tupper vacuum
solution and show that they lead two different cosmological scenarios in 4D.


title: Free zero-range processes on networks

abstract:
  A free zero-range process (FRZP) is a simple stochastic process describing
the dynamics of a gas of particles hopping between neighboring nodes of a
network. We discuss three different cases of increasing complexity: (a) FZRP on
a rigid geometry where the network is fixed during the process, (b) FZRP on a
random graph chosen from a given ensemble of networks, (c) FZRP on a dynamical
network whose topology continuously changes during the process in a way which
depends on the current distribution of particles. The case (a) provides a very
simple realization of the phenomenon of condensation which manifests as the
appearance of a condensate of particles on the node with maximal degree. The
case (b) is very interesting since the averaging over typical ensembles of
graphs acts as a kind of homogenization of the system which makes all nodes
identical from the point of view of the FZRP. In the case (c), the distribution
of particles and the dynamics of network are coupled to each other. The
strength of this coupling depends on the ratio of two time scales: for changes
of the topology and of the FZRP. We will discuss a specific example of that
type of interaction and show that it leads to an interesting phase diagram.


title: Dimensional Duality

abstract:
  We show that string theory on a compact negatively curved manifold,
preserving a U(1)^{b_1} winding symmetry, grows at least b_1 new effective
dimensions as the space shrinks. The winding currents yield a "D-dual"
description of a Riemann surface of genus h in terms of its 2h dimensional
Jacobian torus, perturbed by a closed string tachyon arising as a potential
energy term in the worldsheet sigma model. D-branes on such negatively curved
manifolds also reveal this structure, with a classical moduli space consisting
of a b_1-torus. In particular, we present an AdS/CFT system which offers a
non-perturbative formulation of such supercritical backgrounds. Finally, we
discuss generalizations of this new string duality.


title:
Tail universalities in rank distributions as an algebraic problem: the
  beta-like function

abstract:
  Although power laws of the Zipf type have been used by many workers to fit
rank distributions in different fields like in economy, geophysics, genetics,
soft-matter, networks etc., these fits usually fail at the tails. Some
distributions have been proposed to solve the problem, but unfortunately they
do not fit at the same time both ending tails. We show that many different data
in rank laws, like in granular materials, codons, author impact in scientific
journal, etc. are very well fitted by a beta-like function. Then we propose
that such universality is due to the fact that a system made from many
subsystems or choices, imply stretched exponential frequency-rank functions
which qualitatively and quantitatively can be fitted with the proposed
beta-like function distribution in the limit of many random variables. We prove
this by transforming the problem into an algebraic one: finding the rank of
successive products of a given set of numbers.