title:
The Dynamical State fo the Starless Dense Core FeSt 1-457: A Pulsating
  Globule?

abstract:
  High resolution molecular line observations of CS, HCO+, C18O and N2H+ were
obtained toward the starless globule FeSt 1-457 in order to investigate its
kinematics and chemistry. The HCO+ and CS spectra show clear self-reversed and
asymmetric profiles across the face of the globule. The sense of the observed
asymmetry is indicative of the global presence of expansion motions in the
outer layers of the globule. These motions appear to be subsonic and
significantly below the escape velocity of the globule. Comparison of our
observations with near-infrared extinction data indicate that the globule is
gravitationally bound. Taken together these considerations lead us to suggest
that the observed expansion has its origin in an oscillatory motion of the
outer layers of the globule which itself is likely in a quasi-stable state near
hydrostatic equilibrium. Analysis of the observed linewidths of CO and N2H+
confirm that thermal pressure is the dominant component of the cloud's internal
support. A simple calculation suggests that the dominant mode of pulsation
would be an l = 2 mode with a period of 0.3 Myr. Deformation of the globule due
to the large amplitude l = 2 oscillation may be responsible for the
double-peaked structure of the core detected in high resolution extinction
maps. Detailed comparison of the molecular-line observations and extinction
data provides evidence for significant depletion of C18O and perhaps HCO+ while
N2H+ may be undepleted to a cloud depth of about 40 magnitudes of visual
extinction.


title: Bound state approach to the QCD coupling at low energy scales

abstract:
  We exploit theoretical results on the meson spectrum within the framework of
a Bethe-Salpeter (BS) formalism adjusted for QCD, in order to extract an
``experimental'' coupling \alpha_s^{exp}(Q^2) below 1 GeV by comparison with
the data. Our results for \alpha_s^{exp}(Q^2) exhibit a good agreement with the
infrared safe Analytic Perturbation Theory (APT) coupling from 1 GeV down to
200 MeV. As a main result, we claim that the combined BS-APT theoretical scheme
provides us with a rather satisfactory correlated understanding of very high
and low energy phenomena.


title:
The Dynamical State of the Starless Dense Core FeSt 1-457: A Pulsating
  Globule?


title:
Center-of-Mass Correction in a Relativistic Hartree Approximation
  Including the Meson Degrees of Freedom

abstract:
  The Peierls-Yoccoz projection method is used to study the motion of a
relativistic system of nucleons interacting with sigma and omega mesons. The
nuclear system is described in a mean-field Hartree approach, including
explicitly the meson contribution and the formalism is applied to some selected
N=Z spherical nuclei. The center-of-mass motion correction makes the system too
much bounded, but we show that an appropriate refitting of the model brings the
radii and binding energies close to the experimental values.


title: Nontrivial Geometries: Bounds on the Curvature of the Universe

abstract:
  Probing the geometry of the universe is one of the most important endevours
in cosmology. Current observational data from the Cosmic Microwave Background
anisotropy (CMB), galaxy surveys and type Ia supernovae (SNe Ia) strongly
constrain the curvature of the universe to be close to zero for a universe
dominated by a cosmological constant or dark energy with a constant equation of
state. Here we investigate the role of cosmic priors on deriving these tight
bounds on geometry, by considering a landscape motivated scenario with an
oscillating curvature term. We perform a likelihood analysis of current data
under such a model of non-trivial geometry and find that the uncertainties on
curvature, and correspondingly on parameters of the matter and dark energy
sectors, are larger. Future dark energy experiments together with CMB data from
experiments like Planck could dramatically improve our ability to constrain
cosmic curvature under such models enabling us to probe possible imprints of
quantum gravity.


title: A generalization of Vassiliev's h-principle

abstract:
  This thesis consists of two parts which share only a slight overlap.
  The first part is concerned with the study of ideals in the ring
$C^\infty(M,R)$ of smooth functions on a compact smooth manifold M or more
generally submodules of a finitely generated $C^\infty(M,R)$-module V. We
define a topology on the space of all submodules of V of a fixed finite
codimension d. Its main property is that it is compact Hausdorff and, in the
case of ideals in the ring itself, it contains as a subspace the configuration
space of d distinct unordered points in M and therefore gives a
"compactification" of this configuration space. We present a concrete
description of this space for low codimensions.
  The main focus is then put on the second part which is concerned with a
generalization of Vassiliev's h-principle. This principle in its simplest form
asserts that the jet prolongation map $j^r:C^\infty(M,E)\to\Gamma(J^r(M,E))$,
defined on the space of smooth maps from a compact manifold M to a Euclidean
space E and with target the space of smooth sections of the jet bundle
$J^r(M,E)$, is a cohomology isomorphism when restricted to certain
"nonsingular" subsets (these are defined in terms of a certain subset
$R\subseteq J^r(M,E)$). Our generalization then puts this theorem in a more
general setting of topological $C^\infty(M,R)$-modules. As a reward we get a
strengthening of this result asserting that all the homotopy fibres have zero
homology.


title: Affine surfaces with trivial Makar-Limanov invariant

abstract:
  We study the class of 2-dimensional affine k-domains R satisfying ML(R) = k,
where k is an arbitrary field of characteristic zero. In particular, we obtain
the following result:
  Let R be a localization of a polynomial ring in finitely many variables over
a field of characteristic zero. If ML(R) = K for some field K included in R and
such that R has transcendence degree 2 over K, then R is K-isomorphic to
K[X,Y,Z]/(XY-P(Z)) for some nonconstant polynomial P(Z) in K[Z].


title:
Ferrodistortive instability at the (001) surface of half-metallic
  manganites

abstract:
  We present the structure of the fully relaxed (001) surface of the
half-metallic manganite La0.7Sr0.3MnO3, calculated using density functional
theory within the generalized gradient approximation (GGA). Two relevant
ferroelastic order parameters are identified and characterized: The tilting of
the oxygen octahedra, which is present in the bulk phase, oscillates and
decreases towards the surface, and an additional ferrodistortive Mn
off-centering, triggered by the surface, decays monotonically into the bulk.
The narrow d-like energy band that is characteristic of unrelaxed manganite
surfaces is shifted down in energy by these structural distortions, retaining
its uppermost layer localization. The magnitude of the zero-temperature
magnetization is unchanged from its bulk value, but the effective spin-spin
interactions are reduced at the surface.


title:
Sr2CrOsO6: Endpoint of a spin polarized metal-insulator transition by 5d
  band filling

abstract:
  In the search for new spintronic materials with high spin-polarization at
room-temperature, we have synthesized an osmium based double perovskite with a
Curie-temperature of 725 K. Our combined experimental results confirm the
existence of a sizable induced magnetic moment at the Os site, supported by
band-structure calculations in agreement with a proposed kinetic energy driven
mechanism of ferrimagnetism in these compounds. The intriguing property of
Sr2CrOsO6 is that it is at the endpoint of a metal-insulator transition due to
5d band filling, and at the same time ferrimagnetism and high-spin polarization
is preserved.


title:
A mathematical and computational review of Hartree-Fock SCF methods in
  Quantum Chemistry

abstract:
  We present here a review of the fundamental topics of Hartree-Fock theory in
Quantum Chemistry. From the molecular Hamiltonian, using and discussing the
Born-Oppenheimer approximation, we arrive to the Hartree and Hartree-Fock
equations for the electronic problem. Special emphasis is placed in the most
relevant mathematical aspects of the theoretical derivation of the final
equations, as well as in the results regarding the existence and uniqueness of
their solutions. All Hartree-Fock versions with different spin restrictions are
systematically extracted from the general case, thus providing a unifying
framework. Then, the discretization of the one-electron orbitals space is
reviewed and the Roothaan-Hall formalism introduced. This leads to a exposition
of the basic underlying concepts related to the construction and selection of
Gaussian basis sets, focusing in algorithmic efficiency issues. Finally, we
close the review with a section in which the most relevant modern developments
(specially those related to the design of linear-scaling methods) are commented
and linked to the issues discussed. The whole work is intentionally
introductory and rather self-contained, so that it may be useful for non
experts that aim to use quantum chemical methods in interdisciplinary
applications. Moreover, much material that is found scattered in the literature
has been put together here to facilitate comprehension and to serve as a handy
reference.


title: The Fractal Dimension of the Spectrum of the Fibonacci Hamiltonian

abstract:
  We study the spectrum of the Fibonacci Hamiltonian and prove upper and lower
bounds for its fractal dimension in the large coupling regime. These bounds
show that as $\lambda \to \infty$, $\dim (\sigma(H_\lambda)) \cdot \log
\lambda$ converges to an explicit constant ($\approx 0.88137$). We also discuss
consequences of these results for the rate of propagation of a wavepacket that
evolves according to Schr\"odinger dynamics generated by the Fibonacci
Hamiltonian.


title:
Theory of the friction force using electron cooling as an intrabeam
  scattering process

abstract:
  Using the results found previously for the cooling rates of the emittances,
due to collisions between the electrons and the ions, a result is found for the
friction force acting on the ions. It is shown that the friction force found
here when used to track the ion bunch will give the same emittance cooling
rates as those found using the intrabeam scattering theory for electron cooling
>.For the case of the uniform in space electron bunch distribution, the
friction force found here agrees with the friction force result found with the
usual theory of electron cooling.


title: On the interpolation constant for subadditive operators in Orlicz spaces

abstract:
  Let $1\le p<q\le\infty$ and let $T$ be a subadditive operator acting on
  $L^p$ and $L^q$. We prove that $T$ is bounded on the Orlicz space
  $L^\phi$, where $\phi^{-1}(u)=u^{1/p}\rho(u^{1/q-1/p})$ for some concave
function $\rho$ and \[ \|T\|_{L^\phi\to L^\phi}\le C\max\{\|T\|_{L^p\to
L^p},\|T\|_{L^q\to L^q}\}. \] The interpolation constant $C$, in general, is
less than 4 and, in many cases, we can give much better estimates for $C$. In
particular, if $p=1$ and $q=\infty$, then the classical Orlicz interpolation
theorem holds for subadditive operators with the interpolation constant C=1.
These results generalize our results for linear operators obtained in
\cite{KM01}.


title: The Cuntz semigroup as an invariant for C*-algebras

abstract:
  A category is described to which the Cuntz semigroup belongs and as a functor
into which it preserves inductive limits.


title: Y(5S): What has been learned and what can be learned

abstract:
  We present recent measurements of B and B^0_s production using data collected
on the Y(5S) resonance at CLEO and Belle. We also briefly discuss what can be
learned using sufficiently larger data samples in the future.


title:
The bispectrum of galaxies from high-redshift galaxy surveys: primordial
  non-Gaussianity and non-linear galaxy bias

abstract:
  The greatest challenge in the interpretation of galaxy clustering data from
any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that
the bispectrum provides an excellent determination of linear and non-linear
bias parameters of intermediate and high-z galaxies, when all measurable
triangle configurations down to mildly non-linear scales, where perturbation
theory is still valid, are included. The bispectrum is also a powerful probe of
primordial non-Gaussianity. The planned galaxy surveys at z>2 should yield
constraints on non-Gaussian parameters, f_{NL}^{loc.} and f_{NL}^{eq.}, that
are comparable to, or even better than, those from CMB experiments. We study
how these constraints improve with volume, redshift range, as well as the
number density of galaxies. Finally, we show that a halo occupation
distribution may be used to improve these constraints further by lifting
degeneracies between gravity, bias, and primordial non-Gaussianity.


title: Unifying derived deformation theories

abstract:
  We develop a framework for derived deformation theory, valid in all
characteristics. This gives a model category reconciling local and global
approaches to derived moduli theory. In characteristic 0, we use this to show
that the homotopy categories of DGLAs and SHLAs (L infinity algebras)
considered by Kontsevich, Hinich and Manetti are equivalent, and are compatible
with the derived stacks of Toen--Vezzosi and Lurie. Another application is that
the cohomology groups associated to any classical deformation problem (in any
characteristic) admit the same operations as Andre--Quillen cohomology.


title:
Recoilless resonant neutrino experiment and origin of neutrino
  oscillations

abstract:
  We demonstrate that an experiment with recoilless resonant emission and
absorption of tritium antineutrinos could have an important impact on our
understanding of the origin of neutrino oscillations.


title: Stability of the periodic Toda lattice under short range perturbations

abstract:
  We consider the stability of the periodic Toda lattice (and slightly more
generally of the algebro-geometric finite-gap lattice) under a short range
perturbation. We prove that the perturbed lattice asymptotically approaches a
modulated lattice.
  More precisely, let $g$ be the genus of the hyperelliptic curve associated
with the unperturbed solution. We show that, apart from the phenomenon of the
solitons travelling on the quasi-periodic background, the $n/t$-pane contains
$g+2$ areas where the perturbed solution is close to a finite-gap solution in
the same isospectral torus. In between there are $g+1$ regions where the
perturbed solution is asymptotically close to a modulated lattice which
undergoes a continuous phase transition (in the Jacobian variety) and which
interpolates between these isospectral solutions. In the special case of the
free lattice ($g=0$) the isospectral torus consists of just one point and we
recover the known result.
  Both the solutions in the isospectral torus and the phase transition are
explicitly characterized in terms of Abelian integrals on the underlying
hyperelliptic curve.
  Our method relies on the equivalence of the inverse spectral problem to a
matrix Riemann--Hilbert problem defined on the hyperelliptic curve and
generalizes the so-called nonlinear stationary phase/steepest descent method
for Riemann--Hilbert problem deformations to Riemann surfaces.


title: Superfluidity and magnetism in multicomponent ultracold fermions

abstract:
  We study the interplay between superfluidity and magnetism in a
multicomponent gas of ultracold fermions. Ward-Takahashi identities constrain
possible mean-field states describing order parameters for both pairing and
magnetization. The structure of global phase diagrams arises from competition
among these states as functions of anisotropies in chemical potential, density,
or interactions. They exhibit first and second order phase transition as well
as multicritical points, metastability regions, and phase separation. We
comment on experimental signatures in ultracold atoms.


title: Reply to Comment arXiv:0704.3529v1

abstract:
  In this reply, we show that the author of the Comment arXiv:0704.3529v1
inadvertently provides additional arguments against the use of Hardy functions
as test functions for the Gamow states.


title:
New isotope 44Si and systematics of the production cross sections of the
  most neutron-rich nuclei

abstract:
  The results of measurements of the production of neutron-rich nuclei by the
fragmentation of a 48Ca beam at 142 MeV/u are presented. Evidence was found for
the production of a new isotope that is the most neutron-rich silicon nuclide,
44Si, in a net neutron pick-up process. A simple systematic framework was found
to describe the production cross sections based on thermal evaporation from
excited prefragments that allows extrapolation to other weak reaction products.


title: Algorithms for laying points optimally on a plane and a circle

abstract:
  Two averaging algorithms are considered which are intended for choosing an
optimal plane and an optimal circle approximating a group of points in
three-dimensional Euclidean space.


title: A unified, purely affine theory of gravitation and electromagnetism

abstract:
  In the purely affine formulation of gravity, the gravitational field is
represented by the symmetric part of the Ricci tensor of the affine connection.
The classical electromagnetic field can be represented in this formulation by
the second Ricci tensor of the connection. Such a construction is dynamically
equivalent to the sourceless Einstein-Maxwell equations. We generalize this
construction to the case with sources, represented by the derivative of the
affine Lagrangian density with respect to the connection. We show that the
Maxwell equations with sources emerge for the simplest affine Lagrangian for
matter, while the Einstein and Lorentz equations arise if mass has
electromagnetic origin. We also show that the Maxwell equations replace the
unphysical constraint imposed by the projective invariance of purely affine
Lagrangians that depend explicitly on the connection.


title:
Angular Momentum Transport in Accretion Disks: Scaling Laws in
  MRI-driven Turbulence

abstract:
  We present a scaling law that predicts the values of the stresses obtained in
numerical simulations of saturated MRI-driven turbulence in non-stratified
shearing boxes. It relates the turbulent stresses to the strength of the
vertical magnetic field, the sound speed, the vertical size of the box, and the
numerical resolution and predicts accurately the results of 35 numerical
simulations performed for a wide variety of physical conditions. We use our
result to show that the saturated stresses in simulations with zero net
magnetic flux depend linearly on the numerical resolution and would become
negligible if the resolution were set equal to the natural dissipation scale in
astrophysical disks. We conclude that, in order for MRI-driven turbulent
angular momentum transport to be able to account for the large value of the
effective alpha viscosity inferred observationally, the disk must be threaded
by a significant vertical magnetic field and the turbulent magnetic energy must
be in near equipartition with the thermal energy. This result has important
implications for the spectra of accretion disks and their stability.


title: The interplay of university and industry through the FP5 network

abstract:
  To improve the quality of life in a modern society it is essential to reduce
the distance between basic research and applications, whose crucial roles in
shaping today's society prompt us to seek their understanding. Existing studies
on this subject, however, have neglected the network character of the
interaction between university and industry. Here we use state-of-the-art
network theory methods to analyze this interplay in the so-called Framework
Programme--an initiative which sets out the priorities for the European Union's
research and technological development. In particular we study in the 5th
Framework Programme (FP5) the role played by companies and scientific
institutions and how they contribute to enhance the relationship between
research and industry. Our approach provides quantitative evidence that while
firms are size hierarchically organized, universities and research
organizations keep the network from falling into pieces, paving the way for an
effective knowledge transfer.


title:
Constraining dark energy via baryon acoustic oscillations in the
  (an)isotropic light-cone power spectrum

abstract:
  The measurement of the scale of the baryon acoustic oscillations (BAO) in the
galaxy power spectrum as a function of redshift is a promising method to
constrain the equation-of-state parameter of the dark energy w. To measure the
scale of the BAO precisely, a substantial volume of space must be surveyed. We
test whether light-cone effects are important and whether the scaling relations
used to compensate for an incorrect reference cosmology are in this case
sufficiently accurate. We investigate the degeneracies in the cosmological
parameters and the benefits of using the two-dimensional anisotropic power
spectrum. Finally, we estimate the uncertainty with which w can be measured by
proposed surveys at redshifts of about z=3 and z=1, respectively.
  In the simulated survey we find that light-cone effects are small and that
the simple scaling relations used to correct for the cosmological distortion
work fairly well even for large survey volumes. The analysis of the
two-dimensional anisotropic power spectra enables an independent determination
to be made of the apparent scale of the BAO, perpendicular and parallel to the
line of sight. This is essential for two-parameter w-models, such as the
redshift-dependent dark energy model w=w_0+(1-a)w_a. Using Planck priors for
the matter and baryon density and Delta(H_0)=5% for the Hubble constant, we
estimate that the BAO measurements of future surveys around z=3 and z=1 will be
able to constrain, independently of other cosmological probes, a constant w to
~ 12% and ~ 11% (68% c.l.), respectively.


title:
The Australia Telescope campaign to study southern class I methanol
  masers

abstract:
  The Australia Telescope Compact Array (ATCA) and the Mopra facility have been
used to search for new southern class I methanol masers at 9.9, 25 (J=5) and
104 GHz, which are thought to trace more energetic conditions in the interface
regions of molecular outflows, than the widespread class I masers at 44 and 95
GHz. One source shows a clear outflow association.


title:
Using Transit Timing Observations to Search for Trojans of Transiting
  Extrasolar Planets

abstract:
  Theoretical studies predict that Trojans are likely a frequent byproduct of
planet formation and evolution. We examine the sensitivity of transit timing
observations for detecting Trojan companions to transiting extrasolar planets.
We demonstrate that this method offers the potential to detect terrestrial-mass
Trojans using existing ground-based observatories. We compare the transit
timing variation (TTV) method with other techniques for detecting extrasolar
Trojans and outline the future prospects for this method.


title:
Ongoing Galactic Accretion: Simulations and Observations of Condensed
  Gas in Hot Halos

abstract:
  Ongoing accretion onto galactic disks has been recently theorized to progress
via the unstable cooling of the baryonic halo into condensed clouds. These
clouds have been identified as analogous to the High-Velocity Clouds (HVCs)
observed in HI in our Galaxy. Here we compare the distribution of HVCs observed
around our own Galaxy and extra-planar gas around the Andromeda galaxy to these
possible HVC analogs in a simulation of galaxy formation that naturally
generates these condensed clouds. We find a very good correspondence between
these observations and the simulation, in terms of number, angular size,
velocity distribution, overall flux and flux distribution of the clouds. We
show that condensed cloud accretion only accounts for ~ 0.2 M_solar / year of
the current overall Galactic accretion in the simulations. We also find that
the simulated halo clouds accelerate and become more massive as they fall
toward the disk. The parameter space of the simulated clouds is consistent with
all of the observed HVC complexes that have distance constraints, except the
Magellanic Stream which is known to have a different origin. We also find that
nearly half of these simulated halo clouds would be indistinguishable from
lower-velocity gas and that this effect is strongest further from the disk of
the galaxy, thus indicating a possible missing population of HVCs. These
results indicate that the majority of HVCs are consistent with being infalling,
condensed clouds that are a remnant of Galaxy formation.


title:
Comparison of weak lensing masses and X-ray properties of galaxy
  clusters

abstract:
  We present measurements of the masses of 20 X-ray luminous clusters of
galaxies at intermediate redshifts, determined from a weak lensing analysis of
deep archival R-band data obtained using the Canada-France-Hawaii-Telescope.
Compared to previous work, our analysis accounts for a number of effects that
are typically ignored, but can lead to small biases, or incorrect error
estimates. We derive masses that are essentially model independent and find
that they agree well with measurements of the velocity dispersion of cluster
galaxies and with the results of X-ray studies. Assuming a power law between
the lensing mass and the X-ray temperature, M_2500 T^alpha, we find a best fit
slope of alpha=1.34^{+0.30}_{-0.28}. This slope agrees with self-similar
cluster models and studies based on X-ray data alone. For a cluster with a
temperature of kT=5keV we obtain a mass M_{2500}=(1.4+-0.2)\times
10^{14}h^{-1}Msun in fair agreement with recent Chandra and XMM studies.


title: The Shapes of Molecular Cloud Cores in Orion

abstract:
  We investigate the intrinsic shapes of starless cores in the Orion GMC, using
the prestellar core sample of Nutter and Ward-Thompson (2007), which is based
on submillimeter SCUBA data. We employ a maximum-likelihood method to
reconstruct the intrinsic distribution of ellipsoid axial ratios from the axial
ratios of projected plane-of-the-sky core ellipses. We find that, independently
of the details of the assumed functional form of the distribution, there is a
strong preference for oblate cores of finite thickness. Cores with varying
finite degrees of triaxiality are a better fit than purely axisymmetric cores
although cores close to axisymmetry are not excluded by the data. The incidence
of prolate starless cores in Orion is found to be very infrequent. We also test
the consistency of the observed data with a uniform distribution of intrinsic
shapes, which is similar to those found in gravoturbulent fragmentation
simulations. This distribution is excluded at the 0.1% level. These findings
have important implications for theories of core formation within molecular
clouds.


title: Correlators and fractional statistics in the quantum Hall bulk

abstract:
  We derive single-particle and two-particle correlators of anyons in the
presence of a magnetic field in the lowest Landau level. We show that the
two-particle correlator exhibits signatures of fractional statistics which can
distinguish anyons from their fermionic and bosonic counterparts. These
signatures include the zeroes of the two-particle correlator and its exclusion
behavior. We find that the single-particle correlator in finite geometries
carries valuable information relevant to experiments in which quasiparticles on
the edge of a quantum Hall system tunnel through its bulk.


title:
Optical Bistability in Nonlinear Optical Coupler with Negative Index
  Channel

abstract:
  We discuss a novel kind of nonlinear coupler with one channel filled with a
negative index material (NIM). The opposite directionality of the phase
velocity and the energy flow in the NIM channel facilitates an effective
feedback mechanism that leads to optical bistability and gap soliton formation.


title:
(Non) Gauge Invariance of Wilsonian Effective Actions in
  (Supersymmetric) Gauge Theories : A Critical Discussion

abstract:
  We give a detailed critical discussion of the properties of Wilsonian
effective actions, defined by integrating out all modes above a given scale
$\mu$. In particular, we provide a precise and relatively convenient
prescription how to implement the infrared cutoff $\mu$ in any loop integral
that is manifestly Lorentz invariant and also preserves global linear
symmetries such as e.g. supersymmetry. We discuss the issue of gauge invariance
of effective actions in general and in particular when using background field
gauge. Our prescription for the IR cutoff (as any such prescription) breaks the
gauge symmetry. Using our prescription, we have explicitly computed, at one
loop, many terms of the Wilsonian effective action for general gauge theories,
involving bosonic and fermionic matter fields of arbitrary masses and in
arbitrary representations, exhibiting the non-gauge invariant (as well as the
gauge invariant) terms. However, for supersymmetric gauge theories all
non-gauge invariant terms cancel within each supermultiplet. This is strong
evidence that in supersymmetric gauge theories this indeed defines a Lorentz,
susy and gauge invariant Wilsonian effective action. As a byproduct, we obtain
the explicit one-loop Wilsonian couplings for all higher-derivative terms $F
D^{2n}F$ in the effective action of arbitrary supersymmetric gauge theories.


title:
Formation of Fluctuations in the Molecular Slab via Isobaric Thermal
  Instability

abstract:
  The frictional heating by ion-neutral drift is calculated and its effect on
isobaric thermal instability is carried out. Ambipolar drift heating of
one-dimensional self-gravitating magnetized molecular slab is used under the
assumptions of quasi-magnetohydrostatic and local ionization equilibrium. We
see that ambipolar drift heating is inversely proportional to density and its
value in some regions of the slab can be significantly larger than the average
heating rates of cosmic rays and turbulent motions. The results show that the
isobaric thermal instability can occur in some regions of the slab; therefore
it may produce the slab fragmentation and formation of the AU-scale
condensations.


title:
Symmetric and asymmetric solitons in linearly coupled Bose-Einstein
  condensates trapped in optical lattices

abstract:
  We study spontaneous symmetry breaking in a system of two parallel
quasi-one-dimensional traps, equipped with optical lattices (OLs) and filled
with a Bose-Einstein condensate (BEC). The cores are linearly coupled by
tunneling. Analysis of the corresponding system of linearly coupled
Gross-Pitaevskii equations (GPEs) reveals that spectral bandgaps of the single
GPE split into subgaps. Symmetry breaking in two-component BEC solitons is
studied in cases of the attractive (AA) and repulsive (RR) nonlinearity in both
traps; the mixed situation, with repulsion in one trap and attraction in the
other (RA), is considered too. In all the cases, stable asymmetric solitons are
found, bifurcating from symmetric or antisymmetric ones (and destabilizing
them), in the AA and RR systems, respectively. In either case, bi-stability is
predicted, with a nonbifurcating stable branch, either antisymmetric or
symmetric, coexisting with asymmetric ones. Solitons destabilized by the
bifurcation tend to rearrange themselves into their stable asymmetric
counterparts. The impact of a phase mismatch, between the OLs in the two cores
is also studied. Also considered is a related model, for a binary BEC in a
single-core trap with the OL, assuming that the two species (representing
different spin states of the same atom) are coupled by linear interconversion.
In that case, the symmetry-breaking bifurcations in the AA and RR models switch
their character, if the inter-species nonlinear interaction becomes stronger
than the intra-species nonlinearity.


title:
Using magnetostriction to measure the spin-spin correlation function and
  magnetoelastic coupling in the quantum magnet NiCl$_2$-4SC(NH$_2$)$_2$

abstract:
  We report a method for determining the spatial dependence of the magnetic
exchange coupling, $dJ/dr$, from magnetostriction measurements of a quantum
magnet. The organic Ni $S = 1$ system NiCl$_2$-4SC(NH$_2$)$_2$ exhibits lattice
distortions in response to field-induced canted antiferromagnetism between
$H_{c1} = 2.1$ T and $H_{c2} = 12.6$ T. We are able to model the
magnetostriction in terms of uniaxial stress on the sample created by magnetic
interactions between neighboring Ni atoms along the c-axis. The uniaxial strain
is equal to $(1/E)dJ_c/dx_c < S_{\bf r} \cdot S_{{\bf r}+ {\bf e}_c} >$, where
$E$, $J_c$, $x_c$ and ${\bf e}_c$ are the Young's modulus, the nearest neighbor
(NN) exchange coupling, the variable lattice parameter, and the relative vector
between NN sites along the c-axis. We present magnetostriction data taken at 25
mK together with Quantum Monte Carlo calculations of the NN spin-spin
correlation function that are in excellent agreement with each other. We have
also measured Young's modulus using resonant ultrasound, and we can thus
extract $dJ_c/dx_c = 2.5$ K/$\AA$, yielding a total change in $J_c$ between
$H_{c1}$ and $H_{c2}$ of 5.5 mK or 0.25% in response to an 0.022% change in
length of the sample.


title:
Comment on ``Intensity correlations and mesoscopic fluctuations of
  diffusing photons in cold atoms''

abstract:
  In a recent Letter (Phys. Rev. Lett. \textbf{98}, 083601 (2007),
arXiv:cond-mat/0610804), O. Assaf and E. Akkermans claim that the angular
correlations of the light intensity scattered by a cloud of cold atoms with
internal degeneracy (Zeeman sublevels) of the ground state overcome the usual
Rayleigh law. More precisely, they found that they become exponentially large
with the size of the sample. In what follows, we will explain why their results
are wrong and, in contrary, why the internal degeneracy leads to lower
intensity correlations.


title:
Is there Evidence for a Hubble bubble? The Nature of Type Ia Supernova
  Colors and Dust in External Galaxies

abstract:
  We examine recent evidence from the luminosity-redshift relation of Type Ia
Supernovae (SNe Ia) for the $\sim 3 \sigma$ detection of a ``Hubble bubble'' --
a departure of the local value of the Hubble constant from its globally
averaged value \citep{Jha:07}. By comparing the MLCS2k2 fits used in that study
to the results from other light-curve fitters applied to the same data, we
demonstrate that this is related to the interpretation of SN color excesses
(after correction for a light-curve shape-color relation) and the presence of a
color gradient across the local sample. If the slope of the linear relation
($\beta$) between SN color excess and luminosity is fit empirically, then the
bubble disappears. If, on the other hand, the color excess arises purely from
Milky Way-like dust, then SN data clearly favors a Hubble bubble. We
demonstrate that SN data give $\beta \simeq 2$, instead of the $\beta \simeq 4$
one would expect from purely Milky-Way-like dust. This suggests that either SN
intrinsic colors are more complicated than can be described with a single
light-curve shape parameter, or that dust around SN is unusual. Disentangling
these possibilities is both a challenge and an opportunity for large-survey SN
Ia cosmology.


title: Cosmic Streaming Field at Low Redshift

abstract:
  We study the expansion of the nearby Universe using a sample of Type Ia
supernovae at redshifts below 0.08. These supernovae allow peculiar velocities
to be measured at unprecedented precision. We have investigated in detail the
possibility of a varying Hubble constant with redshift and found no evidence of
a monopole term for the nearby Universe. A large scale streaming motion is
found at an amplitude of about $340^{63}_{-71}$ km/sec, aligned in the
direction of $(l_0, b_0) = (312^{\rm o}.0^{13.5}_{-7.4}, 25^{\rm
o}.7^{8.0}_{-9.2})$, which is close to the direction of the center of Shapley
supercluster of galaxies. The large scale streaming motion is best fit by a
function involving a strong bipolar term. The streaming velocity field extends
from the lowest redshift ($\sim 0.007$) to beyond 0.025 and likely out to even
higher redshifts. The velocity field at redshift below 0.01 can be equally well
described by a dipole field or by the same bipolar streaming velocity field
that reaches out to beyond $z \sim 0.025$. We are also able to deduce a robust
estimate of the random velocity component of the peculiar velocity field.
Within the volume of redshift below 0.01 (weighted average redshift of $\sim$
0.067), this thermal component is found to be about 270 km/sec. After
correcting this smooth streaming motion, we are able to significantly improve
the Hubble expansion fits of these supernovae. The CMAGIC method gives a
dramatic decrease of $\chi^2$ from 90 to 63 for 69 degrees of freedom, and
yields a residual scatter of only 0.12 magnitude; the maximum light method
gives also a moderate improvement.


title: Entanglement transformations using separable operations

abstract:
  We study conditions for the deterministic transformation
$\ket{\psi}\longrightarrow\ket{\phi}$ of a bipartite entangled state by a
separable operation. If the separable operation is a local operation with
classical communication (LOCC), Nielsen's majorization theorem provides
necessary and sufficient conditions. For the general case we derive a necessary
condition in terms of products of Schmidt coefficients, which is equivalent to
the Nielsen condition when either of the two factor spaces is of dimension 2,
but is otherwise weaker. One implication is that no separable operation can
reverse a deterministic map produced by another separable operation, if one
excludes the case where the Schmidt coefficients of $\ket{\psi}$ and are the
same as those of $\ket{\phi}$. The question of sufficient conditions in the
general separable case remains open. When the Schmidt coefficients of
$\ket{\psi}$ are the same as those of $\ket{\phi}$, we show that the Kraus
operators of the separable transformation restricted to the supports of
$\ket{\psi}$ on the factor spaces are proportional to unitaries. When that
proportionality holds and the factor spaces have equal dimension, we find
conditions for the deterministic transformation of a collection of several full
Schmidt rank pure states $\ket{\psi_j}$ to pure states $\ket{\phi_j}$.


title: Sub-ballistic behavior in quantum systems with L\'evy noise

abstract:
  We investigate the quantum walk and the quantum kicked rotor in resonance
subjected to noise with a L\'evy waiting time distribution. We find that both
systems have a sub-ballistic wave function spreading as shown by a power-law
tail of the standard deviation.


title: Magneto-elastic waves in crystals of magnetic molecules

abstract:
  We study magneto-elastic effects in crystals of magnetic molecules. Coupled
equations of motion for spins and sound are derived and the possibility of
strong resonant magneto-acoustic coupling is demonstrated. Dispersion laws for
interacting linear sound and spin excitations are obtained for bulk and surface
acoustic waves. We show that ultrasound can generate inverse population of spin
levels. Alternatively, the decay of the inverse population of spin levels can
generate ultrasound. Possibility of solitary waves of the magnetization
accompanied by the elastic twists is demonstrated.


title: Merging of opinions in game-theoretic probability

abstract:
  This paper gives game-theoretic versions of several results on "merging of
opinions" obtained in measure-theoretic probability and algorithmic randomness
theory. An advantage of the game-theoretic versions over the measure-theoretic
results is that they are pointwise, their advantage over the algorithmic
randomness results is that they are non-asymptotic, but the most important
advantage over both is that they are very constructive, giving explicit and
efficient strategies for players in a game of prediction.


title: Black Hole Giants

abstract:
  We investigate giant and dual giant type BPS configurations in the
near-horizon geometry of a certain 1/16-BPS AdS_5 black hole. By quantising the
space of solutions we count the dual giant configurations and compare with the
black hole entropy. This suggests a missing degeneracy factor which we argue
comes from an angular momentum quantum number. From the D-brane world volume
this arises from BPS electromagnetic waves. We study these waves in the context
of giants and dual giants in the black hole near-horizon geometry. We further
demonstrate that turning on waves on the world-volume of 1/8-BPS dual giants in
AdS_5 x S^5 leads to 1/16-BPS states with an additional angular momentum
quantum number.


title:
Immunohistochemical pitfalls in the demonstration of insulin-degrading
  enzyme in normal and neoplastic human tissues

abstract:
  Previously, we have identified the cytoplasmic zinc metalloprotease
insulin-degrading enzyme(IDE) in human tissues by an immunohistochemical method
involving no antigen retrieval (AR) by pressure cooking to avoid artifacts by
endogenous biotin exposure and a detection kit based on the labeled
streptavidin biotin (LSAB) method. Thereby, we also employed 3% hydrogen
peroxide(H2O2) for the inhibition of endogenous peroxidase activity and
incubated the tissue sections with the biotinylated secondary antibody at room
temperature (RT). We now add the immunohistochemical details that had led us to
this optimized procedure as they also bear a more general relevance when
demonstrating intracellular tissue antigens. Our most important result is that
endogenous peroxidase inhibition by 0.3% H2O2 coincided with an apparently
positive IDE staining in an investigated breast cancer specimen whereas
combining a block by 3% H2O2 with an incubation of the biotinylated secondary
antibody at RT, yet not at 37 degrees Celsius, revealed this specimen as almost
entirely IDE-negative. Our present data caution against three different
immunohistochemical pitfalls that might cause falsely positive results and
artifacts when using an LSAB- and peroxidase-based detection method: pressure
cooking for AR, insufficient quenching of endogenous peroxidases and heating of
tissue sections while incubating with biotinylated secondary antibodies.


title: Selective Control of the Symmetric Dicke Subspace in Trapped Ions

abstract:
  We propose a method of manipulating selectively the symmetric Dicke subspace
in the internal degrees of freedom of N trapped ions. We show that the direct
access to ionic-motional subspaces, based on a suitable tuning of
motion-dependent AC Stark shifts, induces a two-level dynamics involving
previously selected ionic Dicke states. In this manner, it is possible to
produce, sequentially and unitarily, ionic Dicke states with increasing
excitation number. Moreover, we propose a probabilistic technique to produce
directly any ionic Dicke state assuming suitable initial conditions.


title: On the Dirac-Infeld-Plebanski delta function

abstract:
  The present work is a brief review of the progressive search of improper
delta-functions which are of interest in Quantum Mechanics and in the problem
of motion in General Relativity Theory.


title: The symplectic ideal and a double centraliser theorem

abstract:
  We interpret a result of S. Oehms as a statement about the symplectic ideal.
We use this result to prove a double centraliser theorem for the symplectic
group acting on \bigoplus_{r=0}^s\otimes^rV, where V is the natural module for
the symplectic group. This result was obtained in characteristic zero by H.
Weyl. Furthermore we use this to extend to arbitrary connected reductive groups
G with simply connected derived group the earlier result of the author that the
algebra K[G]^g of infinitesimal invariants in the algebra of regular functions
on G is a unique factorisation domain.


title:
Geodesics for Efficient Creation and Propagation of Order along Ising
  Spin Chains

abstract:
  Experiments in coherent nuclear and electron magnetic resonance, and optical
spectroscopy correspond to control of quantum mechanical ensembles, guiding
them from initial to final target states by unitary transformations. The
control inputs (pulse sequences) that accomplish these unitary transformations
should take as little time as possible so as to minimize the effects of
relaxation and decoherence and to optimize the sensitivity of the experiments.
Here we give efficient syntheses of various unitary transformations on Ising
spin chains of arbitrary length. The efficient realization of the unitary
transformations presented here is obtained by computing geodesics on a sphere
under a special metric. We show that contrary to the conventional belief, it is
possible to propagate a spin order along an Ising spin chain with coupling
strength J (in units of Hz), significantly faster than 1/(2J) per step. The
methods presented here are expected to be useful for immediate and future
applications involving control of spin dynamics in coherent spectroscopy and
quantum information processing.


title: Supersymmetric Q Solitons of Arbitrary Genus

abstract:
  We construct "Flying Saucer" solitons in supersymmetric N=2 gauge theory
which is known to support BPS domain walls with a U(1) gauge field localized on
its worldvolume. We demonstrate that this model supports exotic particle-like
solitons whose topology is largely arbitrary: closed orientable surfaces in
three-dimensional space which can have arbitrary genus. In particular, we focus
on Q tori. Q tori and similar solitons of higher genera are obtained by folding
the domain wall into an appropriate surface. Nontrivial cycles on the domain
wall worldvolume (handles) are stabilized by crossed electric and magnetic
fields inside the folded domain wall. Three distinct frameworks are used to
prove the existence of these Flying Saucer solitons and study their properties:
the worldvolume description (including the Dirac-Born-Infeld action), the bulk
theory description in the sigma-model limit, and the bulk theory description in
the thin-edge approximation. In the sigma-model framework the Q torus is shown
to be related to the Hopf Skyrmion studied previously.


title: HD 98800: A 10-Myr-Old Transition Disk

abstract:
  We present the mid-infrared spectrum, obtained with the Spitzer Infrared
Spectrograph (IRS), of HD 98800, a quadruple star system located in the
10-Myr-old TW Hydrae association. It has a known mid-infrared excess that
arises from a circumbinary disk around the B components of the system. The IRS
spectrum confirms that the disk around HD 98800 B displays no excess emission
below about 5.5 micron, implying an optically thick disk wall at 5.9 AU and an
inner, cleared-out region; however, some optically thin dust, consisting mainly
of 3-micron-sized silicate dust grains, orbits the binary in a ring between 1.5
and 2 AU. The peculiar structure and apparent lack of gas in the HD 98800 B
disk suggests that this system is likely already at the debris disks stage,
with a tidally truncated circumbinary disk of larger dust particles and an
inner, second-generation dust ring, possibly held up by the resonances of a
planet. The unusually large infrared excess can be explained by gravitational
perturbations of the Aa+Ab pair puffing up the outer dust ring and causing
frequent collisions among the larger particles.


title:
How short-range attractions impact the structural order,
  self-diffusivity, and viscosity of a fluid

abstract:
  We present molecular simulation data for viscosity, self-diffusivity, and the
local structural ordering of (i) a hard-sphere fluid and (ii) a square-well
fluid with short-range attractions. The latter fluid exhibits a region of
dynamic anomalies in its phase diagram, where its mobility increases upon
isochoric cooling, which is found to be a subset of a larger region of
structural anomalies, in which its pair correlations strengthen upon isochoric
heating. This "cascade of anomalies" qualitatively resembles that found in
recent simulations of liquid water. The results for the hard-sphere and
square-well systems also show that the breakdown of the Stokes-Einstein
relation upon supercooling occurs for conditions where viscosity and
self-diffusivity develop different couplings to the degree of pairwise
structural ordering of the liquid. We discuss how these couplings reflect
dynamic heterogeneities. Finally, we note that the simulation data suggests how
repulsive and attractive glasses may generally be characterized by two distinct
levels of short-range structural order.


title: Heavy Ion Physics at the LHC with the ATLAS Detector

abstract:
  The ATLAS detector at CERN will provide a high-resolution
longitudinally-segmented calorimeter and precision tracking for the upcoming
study of heavy ion collisions at the LHC (sqrt(s_NN)=5520 GeV). The calorimeter
covers |eta|<5 with both electromagnetic and hadronic sections, while the inner
detector spectrometer covers |eta|<2.5. ATLAS will study a full range of
observables necessary to characterize the hot and dense matter formed at the
LHC. Global measurements (particle multiplicities, collective flow) will
provide access into its thermodynamic and hydrodynamic properties. Measuring
complete jets out to 100's of GeV will allow detailed studies of energy loss
and its effect on jets. Quarkonia will provide a handle on deconfinement
mechanisms. ATLAS will also study the structure of the nucleon and nucleus
using forward physics probes and ultraperipheral collisions, both enabled by
segmented Zero Degree Calorimeters.


title:
String tension and removal of lattice coarsening effects in Monte Carlo
  Renormalization Group

abstract:
  We study the computation of the static quark potential under decimations in
the Monte Carlo Renormalization Group (MCRG). Employing a multi-representation
plaquette action, we find that fine-tuning the decimation prescription so that
the MCRG equilibrium self-consistency condition is satisfied produces dramatic
improvement at large distances. In particular, lattice coarsening (change of
effective lattice spacing on action-generated lattices after decimation) is
nearly eliminated. Failure to correctly tune the decimation, on the other hand,
produces large coarsening effects, of order 50% or more, consistent with those
seen in previous studies. We also study rotational invariance restoration at
short distances, where no particular improvement is seen for this action.


title: Effects of mesonic correlations in the QCD phase transition

abstract:
  The finite temperature phase transition of strongly interacting matter is
studied within a nonlocal chiral quark model of the NJL type coupled to a
Polyakov loop. In contrast to previous investigations which were restricted to
the mean-field approximation, mesonic correlations are included by evaluating
the quark-antiquark ring sum. For physical pion masses, we find that the pions
dominate the pressure below the phase transition, whereas above T_c the
pressure is well described by the mean-field approximation result. For large
pion masses, as realized in lattice simulations, the meson effects are
suppressed.


title:
Radio and X-ray images of SNR G18.8+0.3 interacting with molecular
  clouds

abstract:
  New HI images from the VLA Galactic Plane Survey (VGPS) show clear absorption
features associated with the supernova remnant (SNR) G18.8+0.3. High-resolution
$^{13}$CO images reveal that molecular clouds overlap the radio filaments of
G18.8+0.3. The $^{13}$CO emission spectrum over the full velocity range in the
direction of G18.8+0.3 shows two molecular components with high
brightness-temperatureand three molecular components with low
brightness-temperature, all with respective HI absorption. This implies that
these clouds are in front of G18.8+0.3. In the HI images, the highest velocity
absorption feature seen against the continuum image of G18.8+0.3 is at 129 km
s$^{-1}$, which corresponds to the tangent point in this direction. This yields
a lower distance limit of 6.9 kpc for G18.8+0.3. Absence of absorption at
negative velocities gives an upper distance limit of 15 kpc. The broadened
profile at 20$\pm$5 km s$^{-1}$ in the $^{13}$CO emission spectra is a strong
indicator of a possible SNR/CO cloud interaction. Thus, G18.8+0.3 is likely to
be at the distance of about 12 kpc. The upper mass limit and mean density of
the giant CO cloud at 20$\pm$5 km s$^{-1}$ are \sim 6 \times 10^{5} M_{\odot}
and \sim 2 \times 10^{2} cm^{-3}. We find an atomic hydrogen column density in
front of G18.8+0.3 of $N_{HI}$ \sim 2 \times 10^{22} cm^{-2}. The ROSAT PSPC
observations show a diffuse X-ray enhancement apparently associated with part
of the radio shell of G18.8+0.3. Assuming an association, the unabsorbed flux
is 2.2 \times10^{-12} erg cm^{-2} s^{-1}, suggesting an intrinsic luminosity of
3.6 \times 10^{34} erg s^{-1} for G18.8+0.3.


title: Bound entanglement in the XY model

abstract:
  We study the multi-spin entanglement for the 1D anisotropic XY model
concentrating on the simplest case of three-spin entanglement. As compared to
the pairwise entanglement, three-party quantum correlations have a longer range
and they are more robust on increasing the temperature.
  We find regions of the phase diagram of the system where bound entanglement
occurs, both at zero and finite temperature. Bound entanglement in the ground
state can be obtained by tuning the magnetic field. Thermal bound entanglement
emerges naturally due to the effect of temperature on the free ground state
entanglement.


title:
On the Incidence of C IV Absorbers Along the Sightlines to Gamma-Ray
  Bursts

abstract:
  We report on the statistics of strong (W_r > 0.15 A) C IV absorbers at
z=1.5-3.5 toward high-redshift gamma-ray bursts (GRBs). In contrast with a
recent survey for strong Mg II absorption systems at z < 2, we find that the
number of C IV absorbers per unit redshift dN/dz does not show a significant
deviation from previous surveys using quasi-stellar objects (QSOs) as
background sources. We find that the number density of C IV toward GRBs is
dN/dz(z~1.5)= 2.2 +2.8/-1.4, dN/dz(z~2.5)= 2.3 +1.8/-1.1 and dN/dz(z~3.5)= 1.1
+2.6/-0.9. These numbers are consistent with previous C IV surveys using QSO
spectra. Binning the entire dataset, we set a 95% c.l. upper limit to the
excess of C IV absorbers along GRB sightlines at twice the incidence observed
along QSO sightlines. Furthermore, the distribution of equivalent widths of the
GRB and QSO samples are consistent with being drawn from the same parent
population. Although the results for Mg II and C IV absorbers along GRB
sightlines appear to contradict one another, we note that the surveys are
nearly disjoint: the C IV survey corresponds to higher redshift and more highly
ionized gas than the Mg II survey. Nevertheless, analysis on larger statistical
samples may constrain properties of the galaxies hosting these metals (e.g.
mass, dust content) and/or the coherence-length of the gas giving rise to the
metal-line absorption.


title:
Sagnac Rotational Phase Shifts in a Mesoscopic Electron Interferometer
  with Spin-Orbit Interactions

abstract:
  The Sagnac effect is an important phase coherent effect in optical and atom
interferometers where rotations of the interferometer with respect to an
inertial reference frame result in a shift in the interference pattern
proportional to the rotation rate. Here we analyze for the first time the
Sagnac effect in a mesoscopic semiconductor electron interferometer. We include
in our analysis Rashba spin-orbit interactions in the ring. Our results
indicate that spin-orbit interactions increase the rotation induced phase
shift. We discuss the potential experimental observability of the Sagnac phase
shift in such mesoscopic systems.


title: The Truth About Ballistic Coefficients

abstract:
  The ballistic coefficient of a bullet describes how it slows in flight due to
air resistance. This article presents experimental determinations of ballistic
coefficients showing that the majority of bullets tested have their previously
published ballistic coefficients exaggerated from 5-25% by the bullet
manufacturers. These exaggerated ballistic coefficients lead to inaccurate
predictions of long range bullet drop, retained energy and wind drift.


title:
Strain-induced single-domain growth of epitaxial SrRuO3 layers on
  SrTiO3: a high-temperature x-ray diffraction study

abstract:
  Temperature dependent structural phase transitions of SrRuO3 thin films
epitaxially grown on SrTiO3(001) single crystal substrates have been studied
using high-resolution x-ray diffraction. In contrast to bulk SrRuO3, coherently
strained epitaxial layers do not display cubic symmetry up to ~730 oC and
remain tetragonal. Such behavior is believed to be induced by compressive
strain between the SrRuO3 layer and SrTiO3 substrate due to lattice mismatch.
The tetragonal symmetry during growth explains the single domain growth on
miscut SrTiO3 substrates with step edges running along the [100] or [010]
direction.


title: An Acoustic Method for Determining Ballistic Coefficients

abstract:
  This paper presents a method for using a PC soundcard, microphone and a
chronograph to determine bullet BC with an accuracy of 6%. This is useful when
a second chronograph is unavailable or when the projectile accuracy is
insufficient to use a far chronograph.


title: Chirality and Equilibrium Biopolymer Bundles

abstract:
  We use continuum theory to show that chirality is a key thermodynamic control
parameter for the aggregation of biopolymers: chirality produces a stable
disperse phase of hexagonal bundles under moderately poor solvent conditions,
as has been observed in {\it in-vitro} studies of F-actin [O. Pelletier {\it et
al.}, Phys. Rev. Lett. {\bf 91}, 148102 (2003)]. The large characteristic
radius of these chiral bundles is not determined by a mysterious long-range
molecular interaction but by in-plane shear elastic stresses generated by the
interplay between a chiral torque and an unusual, but universal, non-linear
gauge term in the strain tensor of ordered chains that is imposed by rotational
invariance.


title:
Non-saturating magnetoresistance of inhomogeneous conductors: comparison
  of experiment and simulation

abstract:
  The silver chalcogenides provide a striking example of the benefits of
imperfection. Nanothreads of excess silver cause distortions in the current
flow that yield a linear and non-saturating transverse magnetoresistance (MR).
Associated with the large and positive MR is a negative longitudinal MR. The
longitudinal MR only occurs in the three-dimensional limit and thereby permits
the determination of a characteristic length scale set by the spatial
inhomogeneity. We find that this fundamental inhomogeneity length can be as
large as ten microns. Systematic measurements of the diagonal and off-diagonal
components of the resistivity tensor in various sample geometries show clear
evidence of the distorted current paths posited in theoretical simulations. We
use a random resistor network model to fit the linear MR, and expand it from
two to three dimensions to depict current distortions in the third (thickness)
dimension. When compared directly to experiments on Ag$_{2\pm\delta}$Se and
Ag$_{2\pm\delta}$Te, in magnetic fields up to 55 T, the model identifies
conductivity fluctuations due to macroscopic inhomogeneities as the underlying
physical mechanism. It also accounts reasonably quantitatively for the various
components of the resistivity tensor observed in the experiments.


title:
Yang-Mills Theory in 2+1 Dimensions: Coupling of Matter Fields and
  String-breaking Effects

abstract:
  We explore further the Hamiltonian formulation of Yang-Mills theory in 2+1
dimensions in terms of gauge-invariant matrix variables. Coupling to scalar
matter fields is discussed in terms of gauge-invariant fields. We analyze how
the screening of adjoint (and other screenable) representations can arise in
this formalism. A Schrodinger equation is then derived for the gluelump states
which are the daughter states when an adjoint string breaks. A variational
solution of this Schrodinger equation leads to an analytic estimate of the
string-breaking energy which is within 8.8% of the latest lattice estimates.


title: On logical characterization of henselianity

abstract:
  We give some sufficient conditions under which any valued field that admits
quantifier elimination in the Macintyre language is henselian. Then, without
extra assumptions, we prove that if a valued field of characteristic $(0,0)$
has a $\Z$-group as its value group and admits quantifier elimination in the
main sort of the Denef-Pas style language $\mathcal{L}_{RRP}$ then it is
henselian. In fact the proof of this suggests that a quite large class of
Denef-Pas style languages is natural with respect to henselianity.


title:
Phantom crossing, equation-of-state singularities, and local gravity
  constraints in f(R) models

abstract:
  We identify the class of f(R) dark energy models which have a viable
cosmology, i.e. a matter dominated epoch followed by a late-time acceleration.
The deviation from a LambdaCDM model (f=R-Lambda) is quantified by the function
m=Rf_{,RR}/f_{,R}. The matter epoch corresponds to m(r=-1) simeq +0 (where
r=-Rf_{,R}/f) while the accelerated attractor exists in the region 0<m<1. We
find that the equation of state w_DE of all such ``viable'' f(R) models
exhibits two features: w_DE diverges at some redshift z_{c} and crosses the
cosmological constant boundary (``phantom crossing'') at a redshift z_{b}
smaller than z_{c}. Using the observational data of Supernova Ia and Cosmic
Microwave Background, we obtain the constraint m<O(0.1) and we find that the
phantom crossing could occur at z_{b}>1, i.e. within reach of observations. If
we add local gravity constraints, the bound on m becomes very stringent, with m
several orders of magnitude smaller than unity in the region whose density is
much larger than the present cosmological density. The representative models
that satisfy both cosmological and local gravity constraints take the
asymptotic form m(r)=C(-r-1)^p with p>1 as r approaches -1.


title:
A Family of Equations of State Based on Lattice QCD: Impact on Flow in
  Ultrarelativistic Heavy-Ion Collisions

abstract:
  We construct a family of equations of state within a quasiparticle model by
relating pressure, energy density, baryon density and susceptibilities adjusted
to first-principles lattice QCD calculations. The relation between pressure and
energy density from lattice QCD is surprisingly insensitive to details of the
simulations. Effects from different lattice actions, quark masses and lattice
spacings used in the simulations show up mostly in the quark-hadron phase
transition region which we bridge over by a set of interpolations to a hadron
resonance gas equation of state. Within our optimized quasiparticle model we
then examine the equation of state along isentropic expansion trajectories at
small net baryon densities, as relevant for experiments and hydrodynamic
simulations at RHIC and LHC energies. We illustrate its impact on azimuthal
flow anisotropies and transverse momentum spectra of various hadron species.


title: Search for B0->phiK+pi- Decays with Large K+pi- Invariant Mass

abstract:
  Motivated by the polarization anomaly in the B->phi(1020)K*(892) decay, we
extend our search for other K* final states in the decay B0->phi(1020)K^*0 with
the K*0->K+pi- invariant mass above 1.6 GeV. The final states considered
include the K*(1680)0, K3*(1780)0, K4*(2045)0, and a Kpi spin-zero nonresonant
component. We also search for B0->phiDbar0 decay with the same final state. The
analysis is based on a sample of about 384 million BBbar pairs recorded with
the BABAR detector. We place upper limits on the branching fractions
BR(B0->phiK*(1680)0)<3.5*10^-6, BR(B0->phiK3*(1780)0)<2.7*10^-6,
BR(B0->phiK4*(2045)0)<15.3*10^-6, and BR(B0->phiDbar0)<11.7*10^-6 at 90% C.L.
The nonresonant contribution is consistent with the measurements in the lower
invariant mass range.


title: Spontaneous CP Violating Phase as The CKM Matrix Phase

abstract:
  We propose that the CP violating phase in the CKM mixing matrix is identical
to the CP phases responsible for the spontaneous CP violation in the Higgs
potential. A specific multi-Higgs model with Peccei-Quinn (PQ) symmetry is
constructed to realize this idea. The CP violating phase does not vanish when
all Higgs masses become large. There are flavor changing neutral current (FCNC)
interactions mediated by neutral Higgs bosons at the tree level. However,
unlike general multi-Higgs models, the FCNC Yukawa couplings are fixed in terms
of the quark masses and CKM mixing angles. Implications for meson-anti-meson
mixing, including recent data on $D-\bar D$ mixing, and neutron electric dipole
moment (EDM) are studied. We find that the neutral Higgs boson masses can be at
the order of one hundred GeV. The neutron EDM can be close to the present
experimental upper bound.


title: Kinetic k-essence and Quintessence

abstract:
  Dark energy models with non-canonical kinetic energy terms, k-essence, can
have dynamical and sound speed properties distinct from canonical scalar
fields, quintessence. Concentrating on purely kinetic term Lagrangians, which
can be technically natural, we investigate limits on the equation of state
dynamics and sound speed behaviors and the extent to which these models can be
separated from quintessence.


title:
Leader-following coordination of multi-agent systems with coupling time
  delays

abstract:
  In this paper, we consider a leader-following consensus problem of a group of
autonomous agents with time-varying coupling delays. Two different cases of
coupling topologies are investigated. At first, a necessary and sufficient
condition is proved in the case when the interconnection topology is fixed and
directed. Then a sufficient condition is proposed in the case when the coupling
topology is switched and balanced. Numerical examples are also given to
illustrate our results.


title: On the orbital periods of the AM CVn stars HP Librae and V803 Centauri

abstract:
  We analyse high-time-resolution spectroscopy of the AM CVn stars HP Librae
and V803 Centauri, taken with the New Technology Telescope (NTT) and the Very
Large Telescope (VLT) of the European Southern Observatory, Chile.
  We present evidence that the literature value for V803 Cen's orbital period
is incorrect, based on an observed `S-wave' in the binary's spectrogram. We
measure a spectroscopic period P=1596.4+/-1.2s of the S-wave feature, which is
significantly shorter than the 1611-second periods found in previous
photometric studies. We conclude that the latter period likely represents a
`superhump'. If one assumes that our S-wave period is the orbital period, V803
Cen's mass ratio can be expected to be much less extreme than previously
thought, at q~0.07 rather than q~0.016. This relaxes the constraints on the
masses of the components considerably: the donor star does then not need to be
fully degenerate, and the mass of the accreting white dwarf no longer has to be
very close to the Chandrasekhar limit.
  For HP Lib, we similarly measure a spectroscopic period P=1102.8+/-0.2s. This
supports the identification of HP Lib's photometric periods found in the
literature, and the constraints upon the masses derived from them.


title:
Tracking control for multi-agent consensus with an active leader and
  variable topology

abstract:
  In this paper, we consider the coordination control of a group of autonomous
mobile agents with multiple leaders. Different interconnection topologies are
investigated. At first, a necessary and sufficient condition is proved in the
case of fixed interconnection topology. Then a sufficient condition is proposed
when the interconnection topology is switched. With a simple first-order
dynamics model by using the neighborhood rule, both results show that the group
behavior of the agents will converge to the polytope formed by the leaders.


title:
Detection of Crab Giant Pulses Using the Mileura Widefield Array Low
  Frequency Demonstrator Field Prototype System

abstract:
  We report on the detection of giant pulses from the Crab Nebula pulsar at a
frequency of 200 MHz using the field deployment system designed for the Mileura
Widefield Array's Low Frequency Demonstrator (MWA-LFD). Our observations are
among the first high-quality detections at such low frequencies. The measured
pulse shapes are deconvolved for interstellar pulse broadening, yielding a
pulse-broadening time of 670$\pm$100 $\mu$s, and the implied strength of
scattering (scattering measure) is the lowest that is estimated towards the
Crab nebula from observations made so far. The sensitivity of the system is
largely dictated by the sky background, and our simple equipment is capable of
detecting pulses that are brighter than $\sim$9 kJy in amplitude. The brightest
giant pulse detected in our data has a peak amplitude of $\sim$50 kJy, and the
implied brightness temperature is $10^{31.6}$ K. We discuss the giant pulse
detection prospects with the full MWA-LFD system. With a sensitivity over two
orders of magnitude larger than the prototype equipment, the full system will
be capable of detecting such bright giant pulses out to a wide range of
Galactic distances; from $\sim$8 to $\sim$30 kpc depending on the frequency.
The MWA-LFD will thus be a highly promising instrument for the studies of giant
pulses and other fast radio transients at low frequencies.


title: Large deviations for multidimensional SDEs with reflection

abstract:
  The large deviations principles are established for a class of
multidimensional degenerate stochastic differential equations with reflecting
boundary conditions. The results include two cases where the initial conditions
are adapted and anticipated.


title: Planar spin-transfer device with a dynamic polarizer

abstract:
  In planar nano-magnetic devices magnetization direction is kept close to a
given plane by the large easy-plane magnetic anisotropy, for example by the
shape anisotropy in a thin film. In this case magnetization shows effectively
in-plane dynamics with only one angle required for its description. Moreover,
the motion can become overdamped even for small values of Gilbert damping. We
derive the equations of effective in-plane dynamics in the presence of
spin-transfer torques. The simplifications achieved in the overdamped regime
allow to study systems with several dynamic magnetic pieces (``free layers'').
A transition from a spin-transfer device with a static polarizer to a device
with two equivalent magnets is observed. When the size difference between the
magnets is less than critical, the device does not exhibit switching, but goes
directly into the ``windmill'' precession state.


title:
On the Dynamical Ferromagnetic, Quantum Hall, and Relativistic Effects
  on the Carbon Nanotubes Nucleation and Growth Mechanism

abstract:
  The mechanism of carbon nanotube (CNT) nucleation and growth has been a
mystery for over 15 years. Prior models have attempted the extension of older
classical transport mechanisms. In July 2000, a more detailed and accurate
nonclassical, relativistic mechanism was formulated considering the detailed
dynamics of the electronics of spin and orbital rehybridization between the
carbon and catalyst via novel mesoscopic phenomena and quantum dynamics.
Ferromagnetic carbon was demonstrated. Here, quantum (Hall) effects and
relativistic effects of intense many body spin-orbital interactions for novel
orbital rehybridization dynamics (Little Effect) are proposed in this new
dynamical magnetic mechanism. This dynamic ferromagnetic mechanism is proven by
imposing dynamic and static magnetic fields during CNT syntheses and observing
the different influence of these external magnetic environments on the
catalyzing spin currents and spin waves and the resulting CNT formation.


title: How Black Holes Form in High Energy Collisions

abstract:
  We elucidate how black holes form in trans-Planckian collisions. In the rest
frame of one of the incident particles, the gravitational field of the other,
which is rapidly moving, looks like a gravitational shock wave. The shock wave
focuses the target particle down to a much smaller impact parameter. In turn,
the gravitational field of the target particle captures the projectile when the
resultant impact parameter is smaller than its own Schwarzschild radius,
forming a black hole. One can deduce this by referring to the original argument
of escape velocities exceeding the speed of light, which Michell and Laplace
used to discover the existence of black holes.


title: Intrinsic spin Hall effect in platinum metal

abstract:
  Spin Hall effect in metallic Pt is studied with first-principles relativistic
band calculations. It is found that intrinsic spin Hall conductivity (SHC) is
as large as $\sim 2000 (\hbar/e)(\Omega {\rm cm})^{-1}$ at low temperature, and
decreases down to $\sim 200 (\hbar/e)(\Omega {\rm cm})^{-1}$ at room
temperature. It is due to the resonant contribution from the spin-orbit
splitting of the doubly degenerated $d$-bands at high-symmetry $L$ and $X$
points near the Fermi level. By modeling these near degeneracies by effective
Hamiltonian, we show that SHC has a peak near the Fermi energy and that the
vertex correction due to impurity scattering vanishes. We therefore argue that
the large spin Hall effect observed experimentally in platinum is of intrinsic
nature.


title: Moduli of toric vector bundles

abstract:
  We give a presentation of the moduli stack of toric vector bundles with fixed
equivariant total Chern class as a quotient of a fine moduli scheme of framed
bundles by a linear group action. This fine moduli scheme is described
explicitly as a locally closed subscheme of a product of partial flag varieties
cut out by combinatorially specified rank conditions. We use this description
to show that the moduli of rank three toric vector bundles satisfy Murphy's
Law, in the sense of Vakil. The preliminary sections of the paper give a
self-contained introduction to Klyachko's classification of toric vector
bundles.


title: Enhanced negative type for finite metric trees

abstract:
  Finite metric trees are known to have strict 1-negative type. In this paper
we introduce a new family of inequalities that quantify the extent of the
"strictness" of the 1-negative type inequalities for finite metric trees. These
inequalities of "enhanced 1-negative type" are sufficiently strong to imply
that any given finite metric tree must have strict p-negative type for all
values of p in an open interval that contains the number 1. Moreover, these
open intervals can be characterized purely in terms of the unordered
distribution of edge weights that determine the path metric on the particular
tree, and are therefore largely independent of the tree's internal geometry.
  From these calculations we are able to extract a new non linear technique for
improving lower bounds on the maximal p-negative type of certain finite metric
spaces. Some pathological examples are also considered in order to stress
certain technical points.


title: Invariants via word for curves and fronts

abstract:
  We construct the infinite sequence of invariants for curves in surfaces by
using word theory that V. Turaev introduced. For plane closed curves, we add
some extra terms, e.g. the rotation number. From these modified invariants, we
get the Arnold's basic invariants and some other invariants. We also express
how these invariants classify plane closed curves. In addition, we consider
other classes of plane curves: long curves and fronts.


title: Edges and Switches, Tunnels and Bridges

abstract:
  Edge casing is a well-known method to improve the readability of drawings of
non-planar graphs. A cased drawing orders the edges of each edge crossing and
interrupts the lower edge in an appropriate neighborhood of the crossing.
Certain orders will lead to a more readable drawing than others. We formulate
several optimization criteria that try to capture the concept of a "good" cased
drawing. Further, we address the algorithmic question of how to turn a given
drawing into an optimal cased drawing. For many of the resulting optimization
problems, we either find polynomial time algorithms or NP-hardness results.


title:
Determination of SNe explosions frequency distribution function.Method
  and numerical simulations

abstract:
  The method for determination of the Supernovae (SNe) explosions frequency
distribution function based on the assumption of explosions independence are
offered. The method is based on assumption that the sequence of SNe explosions
in an individual galaxy is a Poisson sequence. The essence of the method is in
the determination of statistical moments of the frequency of the SNe explosions
and subsequent determination of distribution function . The program of
numerical simulation has been developed for testing the efficiency of the
method. Numerical simulations show that even for a small mean number of
registered SNe explosions, method allows restoring initial distribution
function. The results of numerical simulations are given.


title: Coupled spin-charge drift-diffusion equations for the Rashba model

abstract:
  Coupled spin-charge drift-diffusion equations are derived for a biased
two-dimensional electron gas with weak Rashba spin-orbit interaction. The basic
equations formally agree with recent results obtained for spin-orbit coupled
small polarons. It is shown that effects of an in-plane electric field on a
homogeneous spin system can completely be described by an associated in-plane
magnetic field. Exploiting this analogy, we predict among other things the
electric-field equivalent of the Hanle effect.


title:
Sur l'holonomie de D-modules arithm\'etiques associ\'es \`a des
  F-isocristaux surconvergents sur des courbes lisses

abstract:
  We show that the arithmetic D-module associated to an overconvergent
F-isocrystal over a smooth curve is holonomic. We first prove that unipotent
F-isocrystals are holonomic D-module by using the fact that such F-isocrystals
come from logarithmic F-isocrystals. We deduce the general case from the
semi-stable theorem for F-isocrystals over curves of Matsuda-Trihan which
relies on the p-adic monodromy theorem independently proved by Andr\'e, Kedlaya
and Mebkhout. The main result has already been proved by D. Caro.


title: Microwave Absorption of Surface-State Electrons on Liquid $^3$He

abstract:
  We have investigated the intersubband transitions of surface state electrons
(SSE) on liquid $^3$He induced by microwave radiation at temperatures from 1.1
K down to 0.01 K. Above 0.4 K, the transition linewidth is proportional to the
density of $^3$He vapor atoms. This proportionality is explained well by Ando's
theory, in which the linewidth is determined by the electron - vapor atom
scattering. However, the linewidth is larger than the calculation by a factor
of 2.1. This discrepancy strongly suggests that the theory underestimates the
electron - vapor atom scattering rate. At lower temperatures, the absorption
spectrum splits into several peaks. The multiple peak structure is partly
attributed to the spatial inhomogeneity of the static holding electric field
perpendicular to the electron sheet.


title: Various Approaches for Predicting Land Cover in Mountain Areas

abstract:
  Using former maps, geographers intend to study the evolution of the land
cover in order to have a prospective approach on the future landscape;
predictions of the future land cover, by the use of older maps and
environmental variables, are usually done through the GIS (Geographic
Information System). We propose here to confront this classical geographical
approach with statistical approaches: a linear parametric model (polychotomous
regression modeling) and a nonparametric one (multilayer perceptron). These
methodologies have been tested on two real areas on which the land cover is
known at various dates; this allows us to emphasize the benefit of these two
statistical approaches compared to GIS and to discuss the way GIS could be
improved by the use of statistical models.


title: Undirected Graphs of Entanglement Two

abstract:
  Entanglement is a complexity measure of directed graphs that origins in fixed
point theory. This measure has shown its use in designing efficient algorithms
to verify logical properties of transition systems. We are interested in the
problem of deciding whether a graph has entanglement at most k. As this measure
is defined by means of games, game theoretic ideas naturally lead to design
polynomial algorithms that, for fixed k, decide the problem. Known
characterizations of directed graphs of entanglement at most 1 lead, for k = 1,
to design even faster algorithms. In this paper we present an explicit
characterization of undirected graphs of entanglement at most 2. With such a
characterization at hand, we devise a linear time algorithm to decide whether
an undirected graph has this property.


title:
Electromagnetic field and radiation for a charge moving along a helical
  trajectory inside a waveguide with dielectric filling

abstract:
  We investigate the electromagnetic field generated by a point charge moving
along a helical trajectory inside a circular waveguide with conducting walls
filled by homogeneous dielectric. The parts corresponding to the radiation
field are separated and the formulae for the radiation intensity are derived
for both TE and TM waves. It is shown that the main part of the radiated quanta
is emitted in the form of the TE waves. Various limiting cases are considered.
The results of the numerical calculations show that the insertion of the
waveguide provides an additional mechanism for tuning the characteristics of
the emitted radiation by choosing the parameters of the waveguide and filling
medium.


title: Mean-Field Magnetohydrodynamics of Accretion Disks

abstract:
  We consider the accretion process in a disk with magnetic fields that are
dragged in from the interstellar medium by gravitational collapse. Two
diffusive processes are at work in the system: (1) "viscous" torques exerted by
turbulent and magnetic stresses, and (2) "resistive" redistribution of mass
with respect to the magnetic flux arising from the imperfect conduction of
current. In steady state, self-consistency between the two rates of drift
requires that a relationship exists between the coefficients of turbulent
viscosity and turbulent resistivity. Ignoring any interactions with a stellar
magnetosphere, we solve the steady-state equations for a magnetized disk under
the gravitational attraction of a mass point and threaded by an amount of
magnetic flux consistent with calculations of magnetized gravitational collapse
in star formation. Our model mean-field equations have an exact analytical
solution that corresponds to magnetically diluted Keplerian rotation about the
central mass point. The solution yields the strength of the magnetic field and
the surface density as functions of radial position in the disk and their
connection with the departure from pure Keplerian rotation in representative
cases. We compare the predictions of the theory with the available observations
concerning T Tauri stars, FU Orionis stars, and low- and high-mass protostars.
Finally, we speculate on the physical causes for high and low states of the
accretion disks that surround young stellar objects. One of the more important
results of this study is the physical derivation of analytic expressions for
the turbulent viscosity and turbulent resistivity.


title: Frugal Colouring of Graphs

abstract:
  A $k$-frugal colouring of a graph $G$ is a proper colouring of the vertices
of $G$ such that no colour appears more than $k$ times in the neighbourhood of
a vertex. This type of colouring was introduced by Hind, Molloy and Reed in
1997. In this paper, we study the frugal chromatic number of planar graphs,
planar graphs with large girth, and outerplanar graphs, and relate this
parameter with several well-studied colourings, such as colouring of the
square, cyclic colouring, and $L(p,q)$-labelling. We also study frugal
edge-colourings of multigraphs.


title: Encoding for the Blackwell Channel with Reinforced Belief Propagation

abstract:
  A key idea in coding for the broadcast channel (BC) is binning, in which the
transmitter encode information by selecting a codeword from an appropriate bin
(the messages are thus the bin indexes). This selection is normally done by
solving an appropriate (possibly difficult) combinatorial problem. Recently it
has been shown that binning for the Blackwell channel --a particular BC-- can
be done by iterative schemes based on Survey Propagation (SP). This method uses
decimation for SP and suffers a complexity of O(n^2). In this paper we propose
a new variation of the Belief Propagation (BP) algorithm, named Reinforced BP
algorithm, that turns BP into a solver. Our simulations show that this new
algorithm has complexity O(n log n). Using this new algorithm together with a
non-linear coding scheme, we can efficiently achieve rates close to the border
of the capacity region of the Blackwell channel.


title: Almost bi-Lipschitz embeddings and almost homogeneous sets

abstract:
  This paper is concerned with embeddings of homogeneous spaces into Euclidean
spaces. We show that any homogeneous metric space can be embedded into a
Hilbert space using an almost bi-Lipschitz mapping (bi-Lipschitz to within
logarithmic corrections). The image of this set is no longer homogeneous, but
`almost homogeneous'. We therefore study the problem of embedding an almost
homogeneous subset $X$ of a Hilbert space $H$ into a finite-dimensional
Euclidean space. In fact we show that if $X$ is a compact subset of a Banach
space and $X-X$ is almost homogeneous then, for $N$ sufficiently large, a
prevalent set of linear maps from $X$ into $\Re^N$ are almost bi-Lipschitz
between $X$ and its image. We are then able to use the Kuratowski embedding of
$(X,d)$ into $L^\infty(X)$ to prove a similar result for compact metric spaces.


title: Batch Processor Sharing with Hyper-Exponential Service Time

abstract:
  We study Batch Processor-Sharing (BPS) queuing model with hyper-exponential
service time distribution and Poisson batch arrival process. One of the main
goals to study BPS is the possibility of its application in size-based
scheduling, which is used in differentiation between Short and Long flows in
the Internet. In the case of hyper-exponential service time distribution we
find an analytical expression of the expected conditional response time for the
BPS queue. We show, that the expected conditional response time is a concave
function of the service time. We apply the received results to the Two Level
Processor-Sharing (TLPS) model with hyper-exponential service time distribution
and find the expression of the expected response time for the TLPS model. TLPS
scheduling discipline can be applied to size-based differentiation in TCP/IP
networks and Web server request handling.


title: Reflection subgroups of Coxeter groups

abstract:
  We use geometry of Davis complex of a Coxeter group to prove the following
result: if G is an infinite indecomposable Coxeter group and $H\subset G$ is a
finite index reflection subgroup then the rank of H is not less than the rank
of G. This generalizes results of math/0305093. We also describe some
properties of the nerves of the group and the subgroup in the case of equal
ranks.


title: The Integrals of Motion for the Deformed Virasoro Algebra

abstract:
  We explicitly construct two classes of infinitly many commutative operators
in terms of the deformed Virasoro algebra. We call one of them local integrals
and the other nonlocal one, since they can be regarded as elliptic deformations
of the local and nonlocal integrals of motion obtained by V.Bazhanov,
S.Lukyanov and Al.Zamolodchikov.


title: An OFDM-CDMA scheme for high data rate UWB applications

abstract:
  In this paper, we investigate a new waveform for UWB systems obtained by the
combination of Orthogonal Frequency Division Multiplex (OFDM) and Code Division
Multiple Access (CDMA). The proposed system, called Spread Spectrum -
Multi-Carrier - Multiple Access (SS-MC-MA) turns out to be a judicious solution
to combat frequency selectivity and narrowband interferers, and to manage the
coexistence of several users and piconets. It is shown that the addition of a
degree of freedom brought by the spreading component of SS-MC-MA allows to
optimize jointly the assignment of the number of used codes and coding rates in
order to make the system more robust. Through simulations, it is demonstrated
that the new system can outperform Multi-Band OFDM Alliance (MBOA) for low data
rates and is able to provide wider range of rates.


title:
Bayesian reconstruction of the cosmological large-scale structure:
  methodology, inverse algorithms and numerical optimization

abstract:
  We address the inverse problem of cosmic large-scale structure reconstruction
from a Bayesian perspective. For a linear data model, a number of known and
novel reconstruction schemes, which differ in terms of the underlying signal
prior, data likelihood, and numerical inverse extra-regularization schemes are
derived and classified. The Bayesian methodology presented in this paper tries
to unify and extend the following methods: Wiener-filtering, Tikhonov
regularization, Ridge regression, Maximum Entropy, and inverse regularization
techniques. The inverse techniques considered here are the asymptotic
regularization, the Jacobi, Steepest Descent, Newton-Raphson,
Landweber-Fridman, and both linear and non-linear Krylov methods based on
Fletcher-Reeves, Polak-Ribiere, and Hestenes-Stiefel Conjugate Gradients. The
structures of the up-to-date highest-performing algorithms are presented, based
on an operator scheme, which permits one to exploit the power of fast Fourier
transforms. Using such an implementation of the generalized Wiener-filter in
the novel ARGO-software package, the different numerical schemes are
benchmarked with 1-, 2-, and 3-dimensional problems including structured white
and Poissonian noise, data windowing and blurring effects. A novel numerical
Krylov scheme is shown to be superior in terms of performance and fidelity.
These fast inverse methods ultimately will enable the application of sampling
techniques to explore complex joint posterior distributions. We outline how the
space of the dark-matter density field, the peculiar velocity field, and the
power spectrum can jointly be investigated by a Gibbs-sampling process. Such a
method can be applied for the redshift distortions correction of the observed
galaxies and for time-reversal reconstructions of the initial density field.


title: Combination of OFDM and CDMA for high data rate UWB

abstract:
  For Wireless Personal Area Network (WPAN) systems, resource allocation
between several users within a piconet and the coexistence of several piconets
are very important points to take into consideration for the optimization of
high data rate Ultra Wide Band (UWB) systems. To improve the performance of the
Multi-Band OFDM (Orthogonal Frequency Division Multiplex) solution proposed by
the Multi-Band OFDM Alliance (MBOA), the addition of a spreading component in
the frequency domain is a good solution since it makes resource allocation
easier and also offers better robustness against channel frequency selectivity
and narrowband interference. The Spread Spectrum - Multi-Carrier - Multiple
Access (SS-MC-MA) system proposed in this article offers not only the
advantages of Multi-Carrier - Coded Division Multiple Access (MC-CDMA) brought
by frequency spreading, but also a more effective dynamic resource allocation
in a multi-user and multi-piconet context. These improvements are obtained
without increasing the complexity of the radio-frequency part compared to the
classical MBOA solution.


title: Phenomenology of the nMSSM from colliders to cosmology

abstract:
  Low energy supersymmetric models provide a solution to the hierarchy problem
and also have the necessary ingredients to solve two of the most outstanding
issues in cosmology: the origin of dark matter and baryonic matter. One of the
most attractive features of this framework is that the relevant physical
processes are related to interactions at the weak scale and therefore may be
tested in collider experiments in the near future. This is true for the Minimal
Supersymmetric Standard Model (MSSM) as well as for its extension with the
addition of one singlet chiral superfield, the so-called nMSSM. It has been
recently shown that within the nMSSM an elegant solution to both the problem of
baryogenesis and dark matter may be found, that relies mostly on the mixing of
the singlet sector with the Higgs sector of the theory. In this work we review
the nMSSM model constraints from cosmology and present the associated collider
phenomenology at the LHC and the ILC. We show that the ILC will efficiently
probe the neutralino, chargino and Higgs sectors, allowing to confront
cosmological observations with computations based on collider measurements. We
also investigate the prospects for a direct detection of dark matter and the
constraints imposed by the current bounds of the electron electric dipole
moment in this model.


title:
Higher order asymptotic formulas for Toeplitz matrices with symbols in
  generalized H\"older spaces

abstract:
  We prove higher order asymptotic formulas for determinants and traces of
finite block Toeplitz matrices generated by matrix functions belonging to
generalized H\"older spaces with characteristic functions from the
Bari-Stechkin class. We follow the approach of B\"ottcher and Silbermann and
generalize their results for symbols in standard H\"older spaces.


title:
Physical properties of the jet in 0836+710 revealed by its transversal
  structure

abstract:
  Studying the internal structure of extragalactic jets is crucial for
understanding their physics. The Japanese-led space VLBI project VSOP has
presented an opportunity for such studies, by reaching baseline lengths of up
to 36,000 km and resolving structures down to an angular size of $\approx 0.3$
mas at 5 GHz. VSOP observations of the jet in 0836+710 at 1.6 and 5 GHz have
enabled tracing of the radial structure of the flow on scales from 2 mas to 200
mas along the jet and determination of the wavelengths of individual
oscillatory modes responsible for the formation of the structure observed. We
apply linear stability analysis to identify the oscillatory modes with modes of
Kelvin-Helmholtz instability that match the wavelengths of the structures
observed. We find that the jet structure in 0836+710 can be reproduced by the
helical surface mode and a combination of the helical and elliptic body modes
of Kelvin-Helmholtz instability. Our results indicate that the jet is
substantially stratified and different modes of the instability grow inside the
jet at different distances to the jet axis. The helical surface mode can be
driven externally, and we discuss the implications of the driving frequency on
the physics of the active nucleus in 0836+710.


title:
Absence of Conventional Spin-Glass Transition in the Ising Dipolar
  System LiHo_xY_{1-x}F_4

abstract:
  The magnetic properties of single crystals of LiHo_xY_{1-x}F_4 with x=16.5%
and x=4.5% were recorded down to 35 mK using a micro-SQUID magnetometer. While
this system is considered as the archetypal quantum spin glass, the detailed
analysis of our magnetization data indicates the absence of a phase transition,
not only in a transverse applied magnetic field, but also without field. A
zero-Kelvin phase transition is also unlikely, as the magnetization seems to
follow a non-critical exponential dependence on the temperature. Our analysis
thus unmasks the true, short-ranged nature of the magnetic properties of the
LiHo_xY_{1-x}F_4 system, validating recent theoretical investigations
suggesting the lack of phase transition in this system.


title: Optimal relocation strategies for spatially mobile consumers

abstract:
  We develop a model of the behaviour of a dynamically optimizing economic
agent who makes consumption-saving and spatial relocation decisions. We
formulate an existence result for the model, derive the necessary conditions
for optimality and study the behaviour of the economic agent, focusing on the
case of a wage distribution with a single maximum.


title: Mixing navigation on networks

abstract:
  In this Letter, we proposed a mixing navigation mechanism, which interpolates
between random-walk and shortest-path protocol. The navigation efficiency can
be remarkably enhanced via a few routers. Some advanced strategies are also
designed: For non-geographical scale-free networks, the targeted strategy with
a tiny fraction of routers can guarantee an efficient navigation with low and
stable delivery time almost independent of network size. For geographical
localized networks, the clustering strategy can simultaneously increase the
efficiency and reduce the communication cost. The present mixing navigation
mechanism is of significance especially for information organization of
wireless sensor networks and distributed autonomous robotic systems.


title: Existence and uniqueness of optimal maps on Alexandrov spaces

abstract:
  The purpose of this paper is to show that in a finite dimensional metric
space with Alexandrov's curvature bounded below, Monge's transport problem for
the quadratic cost admits a unique solution.


title:
The Garching-Bonn Deep Survey (GaBoDS) Wide-Field-Imaging Reduction
  Pipeline

abstract:
  We introduce our publicly available Wide-Field-Imaging reduction pipeline
THELI. The procedures applied for the efficient pre-reduction and astrometric
calibration are presented. A special emphasis is put on the methods applied to
the photometric calibration. As a test case the reduction of optical data from
the ESO Deep Public Survey including the WFI-GOODS data is described. The
end-products of this project are now available via the ESO archive Advanced
Data Products section.


title: Experimental local realism tests without fair sampling assumption

abstract:
  Following the theoretical suggestion of Ref. [1,2], we present experimental
results addressed to test restricted families of local realistic models, but
without relying on the fair sampling assumption.