title: Static structure factor for graphene in a magnetic field

abstract:
  A close study is made of the static structure factor for graphene in a
magnetic field at integer filling factors nu, with focus on revealing possible
signatures of "relativistic" quantum field theory in the low-energy physics of
graphene. It is pointed out, in particular, that for graphene even the vacuum
state has a nonzero density spectral weight, which, together with the structure
factor for all nu, grows significantly with increasing wave vector; such
unusual features of density correlations are a "relativistic" effect deriving
from massless Dirac quasiparticles in graphene. Remarkably it turns out that
the zero-energy Landau levels of electrons or holes, characteristic to
graphene, remain indistinguishable in density response from the vacuum state,
although they are distinct in Hall conductance.


title: Magnetotransport of electrons in quantum Hall systems

abstract:
  Recent theoretical results on magnetotransport of electrons in a 2D system in
the range of moderately strong transverse magnetic fields are reviewed. The
phenomena discussed include: quasiclassical memory effects in systems with
various types of disorder, transport in lateral superlattices,
interaction-induced quantum magnetoresistance, quantum magnetooscillations in
dc and ac transport, and oscillatory microwave photoconductivity.


title: On relationships among Chern-Simons theory, BF theory and matrix model

abstract:
  Chern-Simons theory on a U(1) bundle over a Riemann surface \Sigma_g of genus
g is dimensionally reduced to BF theory with a mass term, which is equivalent
to the two-dimensional Yang-Mills on \Sigma_g. We show that the former is
inversely obtained from the latter by the extended matrix T-duality developed
in hep-th/0703021. For the case of g=0 (i.e. S^2), the U(1) bundle represents
the lens space S^3/Z_p. We find that in this case both the Chern-Simons theory
and the BF theory with the mass term are realized in a matrix model. We also
construct Wilson loops in the matrix model that correspond to those in the
Chern-Simons theory on S^3.


title:
The Schur transformation for Nevanlinna functions: operator
  representations, resolvent matrices, and orthogonal polynomials

abstract:
  A Nevanlinna function is a function which is analytic in the open upper half
plane and has a non-negative imaginary part there. In this paper we study a
fractional linear transformation for a Nevanlinna function $n$ with a suitable
asymptotic expansion at $\infty$, that is an analogue of the Schur
transformation for contractive analytic functions in the unit disc. Applying
the transformation $p$ times we find a Nevanlinna function $n_p$ which is a
fractional linear transformation of the given function $n$. The main results
concern the effect of this transformation to the realizations of $n$ and $n_p$,
by which we mean their representations through resolvents of self-adjoint
operators in Hilbert space. Our tools are block operator matrix
representations, $u$--resolvent matrices, and reproducing kernel Hilbert
spaces.


title:
Scaling algebras and pointlike fields: A nonperturbative approach to
  renormalization

abstract:
  We present a method of short-distance analysis in quantum field theory that
does not require choosing a renormalization prescription a priori. We set out
from a local net of algebras with associated pointlike quantum fields. The net
has a naturally defined scaling limit in the sense of Buchholz and Verch; we
investigate the effect of this limit on the pointlike fields. Both for the
fields and their operator product expansions, a well-defined limit procedure
can be established. This can always be interpreted in the usual sense of
multiplicative renormalization, where the renormalization factors are
determined by our analysis. We also consider the limits of symmetry actions. In
particular, for suitable limit states, the group of scaling transformations
induces a dilation symmetry in the limit theory.


title: Infinite groups with fixed point properties

abstract:
  We construct finitely generated groups with strong fixed point properties.
Let $\mathcal{X}_{ac}$ be the class of Hausdorff spaces of finite covering
dimension which are mod-$p$ acyclic for at least one prime $p$. We produce the
first examples of infinite finitely generated groups $Q$ with the property that
for any action of $Q$ on any $X\in \mathcal{X}_{ac}$, there is a global fixed
point. Moreover, $Q$ may be chosen to be simple and to have Kazhdan's property
(T). We construct a finitely presented infinite group $P$ that admits no
non-trivial action by diffeomorphisms on any smooth manifold in
$\mathcal{X}_{ac}$. In building $Q$, we exhibit new families of hyperbolic
groups: for each $n\geq 1$ and each prime $p$, we construct a non-elementary
hyperbolic group $G_{n,p}$ which has a generating set of size $n+2$, any proper
subset of which generates a finite $p$-group.


title:
A parametric study of the lensing properties of dodecagonal photonic
  quasicrystals

abstract:
  We present a study of the lensing properties of two-dimensional (2-D)
photonic quasicrystal (PQC) slabs made of dielectric cylinders arranged
according to a 12-fold-symmetric square-triangle aperiodic tiling. Our
full-wave numerical analysis confirms the results recently emerged in the
technical literature and, in particular, the possibility of achieving focusing
effects within several frequency regions. However, contrary to the original
interpretation, such focusing effects turn out to be critically associated to
local symmetry points in the PQC slab, and strongly dependent on its thickness
and termination. Nevertheless, our study reveals the presence of some peculiar
properties, like the ability to focus the light even for slabs with a reduced
lateral width, or beaming effects, which render PQC slabs potentially
interesting and worth of deeper investigation. Key words: Photonic
quasicrystals; negative refraction; superlensing.


title: Quantum effects in atomically perfect specular spin valve structures

abstract:
  A simple tight-binding theoretical model is proposed for spin dependent,
current-in-plane transport in highly coherent spin valve structures under
specularity conditions. Using quantum-mechanically coherent and spatially
quantized Fermi states in the considered multilayered system, a system of
partial Boltzmann kinetic equations is built for relevant subbands to yield the
expressions for conductance in parallel or antiparallel spin valve states and
thus for the magneto-conductance. It is shown that specularity favors the
magnetoresistance to reach its theoretical maximum for this structure close to
100%. This result is practically independent of the model parameters, in
particular it does not even need that lifetimes of majority and minority
carriers be different (as necessary for the quasiclassical regimes). The main
MR effect in the considered limit is due to the transformation of coherent
quantum states, induced by the relative rotation of magnetization in the FM
layers. Numerical calculation based on the specific Boltzmann equation with an
account of spin-dependent specular reflection at the interfaces is also
performed for a typical choice of material parameters.


title: Radial Dependence of Extinction in Parent Galaxies of Supernovae

abstract:
  The problem of extinction is the most important issue to be dealt with in the
process of obtaining true absolute magnitudes of core-collapse (including
stripped-envelope) supernovae (SNe). The plane-parallel model, widely used in
the past, was shown not to describe extinction adequately. We try to apply an
alternative model which introduces radial dependance of extinction in parent
galaxies of supernovae. For calculating extinction in our Galaxy we use two
different methods and compare the results obtained. Our analysis is primarily
focused on a chosen sample of stripped-envelope SNe (Ib/c) for which we find
intrinsic peak absolute magnitude $\mathrm{M}_{\mathrm{B}}^{0}=-17.80\pm 0.43$.


title:
Gauge-invariant analysis of perturbations in Chaplygin gas unified
  models of dark matter and dark energy

abstract:
  We exploit the gauge-invariant formalism to analyse the perturbative
behaviour of two cosmological models based on the generalized Chaplygin gas
describing both dark matter and dark energy in the present Universe. In the
first model we consider the generalized Chaplygin gas alone, while in the
second one we add a baryon component to it. We extend our analysis also into
the parameter range $\alpha > 1$, where the generalized Chaplygin gas sound
velocity can be larger than that of light. In the first model we find that the
matter power spectrum is compatible with the observed one only for $\alpha <
10^{-5}$, which makes the generalized Chaplygin gas practically
indistinguishable from $\Lambda$CDM. In the second model we study the evolution
of inhomogeneities of the baryon component. The theoretical power spectrum is
in good agreement with the observed one for almost all values of $\alpha$.
However, the growth of inhomogeneities seems to be particularly favoured either
for sufficiently small values of $\alpha$ or for $\alpha \gtrsim 3$. Thus, it
appears that the viability of the generalized Chaplygin gas as a cosmological
model is stronger when its sound velocity is superluminal. We show that in this
case the generalized Chaplygin gas equation of state can be changed in an
unobservable region in such a way that its equivalent $k$-essence microscopical
model has no problems with causality.


title:
Effects of Friction and Disorder on the Quasi-Static Response of
  Granular Solids to a Localized Force

abstract:
  The response to a localized force provides a sensitive test for different
models of stress transmission in granular solids. The elasto-plastic models
traditionally used by engineers have been challenged by theoretical and
experimental results which suggest a wave-like (hyperbolic) propagation of the
stress, as opposed to the elliptic equations of static elasticity. Numerical
simulations of two-dimensional granular systems subject to a localized external
force are employed to examine the nature of stress transmission in these
systems as a function of the magnitude of the applied force, the frictional
parameters and the disorder (polydispersity). The results indicate that in
large systems (typically considered by engineers), the response is close to
that predicted by isotropic elasticity whereas the response of small systems
(or when sufficiently large forces are applied) is strongly anisotropic. In the
latter case the applied force induces changes in the contact network
accompanied by frictional sliding. The larger the coefficient of static
friction, the more extended is the range of forces for which the response is
elastic and the smaller the anisotropy. Increasing the degree of polydispersity
(for the range studied, up to 25%) decreases the range of elastic response.
This article is an extension of a previously published letter [1].


title: A 3D Automated Classification Scheme for the TAUVEX data pipeline

abstract:
  In order to develop a pipeline for automated classification of stars to be
observed by the TAUVEX ultraviolet space Telescope, we employ an artificial
neural network (ANN) technique for classifying stars by using synthetic spectra
in the UV region from 1250\AA to 3220\AA as the training set and International
Ultraviolet Explorer (IUE) low resolution spectra as the test set. Both the
data sets have been pre-processed to mimic the observations of the TAUVEX
ultraviolet imager. We have successfully classified 229 stars from the IUE low
resolution catalog to within 3-4 spectral sub-class using two different
simulated training spectra, the TAUVEX spectra of 286 spectral types and UVBLUE
spectra of 277 spectral types. Further, we have also been able to obtain the
colour excess (i.e. E(B-V) in magnitude units) or the interstellar reddening
for those IUE spectra which have known reddening to an accuracy of better than
0.1 magnitudes. It has been shown that even with the limitation of data from
just photometric bands, ANNs have not only classified the stars, but also
provided satisfactory estimates for interstellar extinction. The ANN based
classification scheme has been successfully tested on the simulated TAUVEX data
pipeline. It is expected that the same technique can be employed for data
validation in the ultraviolet from the virtual observatories. Finally, the
interstellar extinction estimated by applying the ANNs on the TAUVEX data base
would provide an extensive extinction map for our galaxy and which could in
turn be modeled for the dust distribution in the galaxy.


title:
Fully frustrated Josephson junction ladders with Mobius boundary
  conditions as topologically protected qubits

abstract:
  We show how to realize a ``protected'' qubit by using a fully frustrated
Josephson Junction ladder (JJL) with Mobius boundary conditions. Such a system
has been recently studied within a twisted conformal field theory (CFT)
approach (Mod. Phys. Lett. A 15 (2000) 1679; Nucl. Phys. B 641 (2002) 547) and
shown to develop the phenomenon of flux fractionalization (Eur. Phys. J. B 49
(2006) 83). The relevance of a ``closed'' geometry has been fully exploited in
relating the topological properties of the ground state of the system to the
presence of half flux quanta and the emergence of a topological order has been
predicted (JSTAT (2005) P03006). In this letter the stability and
transformation properties of the ground states under adiabatic magnetic flux
change are analyzed and the deep consequences on the realization of a solid
state qubit, protected from decoherence, are presented.


title:
Evolution equations of the probabilistic generalization of the Voigt
  profile function

abstract:
  The spectrum profile that emerges in molecular spectroscopy and atmospheric
radiative transfer as the combined effect of Doppler and pressure broadenings
is known as the Voigt profile function. Because of its convolution integral
representation, the Voigt profile can be interpreted as the probability density
function of the sum of two independent random variables with Gaussian density
(due to the Doppler effect) and Lorentzian density (due to the pressure
effect). Since these densities belong to the class of symmetric L\'evy stable
distributions, a probabilistic generalization is proposed as the convolution of
two arbitrary symmetric L\'evy densities. We study the case when the widths of
the considered distributions depend on a scale-factor $\tau$ that is
representative of spatial inhomogeneity or temporal non-stationarity. The
evolution equations for this probabilistic generalization of the Voigt function
are here introduced and interpreted as generalized diffusion equations
containing two Riesz space-fractional derivatives, thus classified as
space-fractional diffusion equations of double order.

categories: math-ph cond-mat.stat-mech math.MP math.PR


title:
On the optimization of the principal eigenvalue for single-centre
  point-interaction operators in a bounded region

abstract:
  We investigate relations between spectral properties of a single-centre
point-interaction Hamiltonian describing a particle confined to a bounded
domain $\Omega\subset\mathbb{R}^{d},\: d=2,3$, with Dirichlet boundary, and the
geometry of $\Omega$. For this class of operators Krein's formula yields an
explicit representation of the resolvent in terms of the integral kernel of the
unperturbed one, $(-\Delta_{\Omega}^{D}+z) ^{-1}$. We use a moving plane
analysis to characterize the behaviour of the ground-state energy of the
Hamiltonian with respect to the point-interaction position and the shape of
$\Omega$, in particular, we establish some conditions showing how to place the
interaction to optimize the principal eigenvalue.


title:
Magnetic vortices for a Ginzburg-Landau type energy with discontinuous
  constraint

abstract:
  This paper is devoted to an analysis of vortex-nucleation for a
Ginzburg-Landau functional with discontinuous constraint. This functional has
been proposed as a model for vortex-pinning, and usually accounts for the
energy resulting from the interface of two superconductors. The critical
applied magnetic field for vortex nucleation is estimated in the London
singular limit, and as a by-product, results concerning vortex-pinning and
boundary conditions on the interface are obtained.


title: Fractional microwave-induced resistance oscillations

abstract:
  We develop a systematic theory of microwave-induced oscillations in
magnetoresistivity of a 2D electron gas in the vicinity of fractional harmonics
of the cyclotron resonance, observed in recent experiments. We show that in the
limit of well-separated Landau levels the effect is dominated by the
multiphoton inelastic mechanism. At moderate magnetic field, two single-photon
mechanisms become important. One of them is due to resonant series of multiple
single-photon transitions, while the other originates from microwave-induced
sidebands in the density of states of disorder-broadened Landau levels.


title: The periodicity of the eta Carinae events

abstract:
  Extensive spectral observations of eta Carinae over the last cycle, and
particularly around the 2003.5 low excitation event, have been obtained. The
variability of both narrow and broad lines, when combined with data taken from
two earlier cycles, reveal a common and well defined period. We have combined
the cycle lengths derived from the many lines in the optical spectrum with
those from broad-band X-rays, optical and near-infrared observations, and
obtained a period length of 2022.7+-1.3 d.
  Spectroscopic data collected during the last 60 years yield an average period
of 2020+-4 d, consistent with the present day period. The period cannot have
changed by more than $\Delta$P/P=0.0007 since 1948. This confirms the previous
claims of a true, stable periodicity, and gives strong support to the binary
scenario. We have used the disappearance of the narrow component of HeI 6678 to
define the epoch of the Cycle 11 minimum, T_0=JD 2,452,819.8. The next event is
predicted to occur on 2009 January 11 (+-2 days). The dates for the start of
the minimum in other spectral features and broad-bands is very close to this
date, and have well determined time delays from the HeI epoch.


title: The role of help in Classical and Quantum Zero-Knowledge

abstract:
  We study the role of help in Non-Interactive Zero-Knowledge protocols and its
relation to the standard interactive model. In the classical case, we show that
help and interaction are equivalent, answering an open question of Ben-Or and
Gutfreund. This implies a new complete problem for the class SZK, the Image
Intersection Density. For this problem, we also prove a polarization lemma
which is stronger than the previously known one.
  In the quantum setting, we define the notion of quantum help and show in a
more direct way that help and interaction are again equivalent. Moreover, we
define quantum Non-Interactive Zero-Knowledge with classical help and prove
that it is equal to the class of languages that have classical honest-Verifier
Zero Knowledge protocols secure against quantum Verifiers. Last, we provide new
complete problems for all these quantum classes.
  Similar results were independently discovered by Dragos Florin Ciocan and
Salil Vadhan.


title:
Decoupling in the Similarity Renormalization Group for Nucleon-Nucleon
  Forces

abstract:
  Decoupling via the Similarity Renormalization Group (SRG) of low-energy
nuclear physics from high-energy details of the nucleon-nucleon interaction is
examined for two-body observables and few-body binding energies. The universal
nature of this decoupling is illustrated and errors from suppressing
high-momentum modes above the decoupling scale are shown to be perturbatively
small.


title:
Production and Testing of the LHCb Outer Tracker Front End Readout
  Electronics

abstract:
  The LHCb Outer Tracker is a straw drift detector with a modular design and a
total of 53760 readout channels distributed over a sensitive area of 12 double
layers of 6x5 m2 each. The main electronics readout requirement is the precise
(0.5 ns) drift time measurement at an occupancy of 4% and 1 MHz readout. A
total of 128 channels are read out by one Front-End box. About half of the
FE-Boxes have been built. Quality Assurance during the production has been
performed on single FE-Box components. The assembled FE-Box is finally
commissioned using a special FE-Tester. The FE-Tester is a programmable pulser
with a time resolution of 150 ps capable to simulate all the functionality of
the readout mimicking the real detector. Consequently, problems have been found
and solved resulting in good overall performance.


title: Uniruled symplectic divisors

abstract:
  This is a paper devoted to the symplectic birational geometry program where
many basic notions are defined in terms of genus 0 GW invariants. We show that
the existence of a positive uniruled symplectic divisor often implies that the
ambient manifold has a nonzero uniruled genus 0 GW invariant, hence is uniruled
as well. This confirms a part of the dichotomy on uniruled symplectic divisors.
In addition, it gives a rather general construction of uniruled symplectic
manifolds, generalizing some beautiful results of McDuff.


title:
HIRDES - The High-Resolution Double-Echelle Spectrograph for the World
  Space Observatory Ultraviolet (WSO/UV)

abstract:
  The World Space Observatory Ultraviolet (WSO/UV) is a multi-national project
grown out of the needs of the astronomical community to have future access to
the UV range. WSO/UV consists of a single UV telescope with a primary mirror of
1.7m diameter feeding the UV spectrometer and UV imagers. The spectrometer
comprises three different spectrographs, two high-resolution echelle
spectrographs (the High-Resolution Double-Echelle Spectrograph, HIRDES) and a
low-dispersion long-slit instrument. Within HIRDES the 102-310nm spectral band
is split to feed two echelle spectrographs covering the UV range 174-310nm and
the vacuum-UV range 102-176nm with high spectral resolution (R>50,000). The
technical concept is based on the heritage of two previous ORFEUS SPAS
missions. The phase-B1 development activities are described in this paper
considering performance aspects, design drivers, related trade-offs (mechanical
concepts, material selection etc.) and a critical functional and environmental
test verification approach. The current state of other WSO/UV scientific
instruments (imagers) is also described.


title: Observational Window Functions in Planet Transit Searches

abstract:
  Window functions describe, as a function of orbital period, the probability
that an existing planetary transit is detectable in one's data for a given
observing strategy. We show the dependence of this probability upon several
strategy and astrophysical parameters, such as length of observing run,
observing cadence, length of night, and transit duration. The ability to detect
a transit is directly related to the intrinsic noise of the observations. In
our simulations of the window function, we explicitly address non-correlated
(gaussian or white) noise and correlated (red) noise and discuss how these two
different noise components affect window functions in different manners.


title:
Correlation of energy density in deconfining SU(2) Yang-Mills
  thermodynamics

abstract:
  We compute the two-point correlation of the energy density for the massless
mode in deconfining SU(2) Yang-Mills thermodynamics and point towards a
possible application for the physics of cold, dilute, and stable clouds of
atomic hydrogen within the Milky Way.


title: Algebraic fidelity decay for local perturbations

abstract:
  From a reflection measurement in a rectangular microwave billiard with
randomly distributed scatterers the scattering and the ordinary fidelity was
studied. The position of one of the scatterers is the perturbation parameter.
Such perturbations can be considered as {\em local} since wave functions are
influenced only locally, in contrast to, e. g., the situation where the
fidelity decay is caused by the shift of one billiard wall. Using the
random-plane-wave conjecture, an analytic expression for the fidelity decay due
to the shift of one scatterer has been obtained, yielding an algebraic $1/t$
decay for long times. A perfect agreement between experiment and theory has
been found, including a predicted scaling behavior concerning the dependence of
the fidelity decay on the shift distance. The only free parameter has been
determined independently from the variance of the level velocities.


title:
Coherent control of light field with electromagnetically induced
  transparency in a dark state Raman coherent tripod system

abstract:
  The coherent superposition of two-atomic levels induced by coherent
population trapping is employed in a standard $\Lambda$ type scheme to form a
tripod-like system. A weak probe pulse scanning across the system is shown to
experience a crossover from absorption to transparent and then to
amplification. Consequently the group velocity of the probe pulse can be
controlled to propagate either as a subluminal, a standard, a superluminal or
even a negative speed. It is shown that the propagation behavior of the light
field is entirely determined and controlled by the initial states of the
coherent superposition.


title: Spectral Properties and Stability of Self-Similar Wave Maps

abstract:
  In this thesis the Cauchy problem and in particular the question of
singularity formation for co--rotational wave maps from 3+1 Minkowski space to
the three--sphere $S^3$ is studied. Numerics indicate that self--similar
solutions of this model play a crucial role in dynamical time evolution. In
particular, it is conjectured that a certain solution $f_0$ defines a universal
blow up pattern in the sense that the future development of a large set of
generic blow up initial data approaches $f_0$. Thus, singularity formation is
closely related to stability properties of self--similar solutions.
  In this work, the problem of linear stability is studied by functional
analytic methods. In particular, a complete spectral analysis of the
perturbation operators is given and well--posedness of the linearized Cauchy
problem is proved by means of semigroup theory and, alternatively, the
functional calculus for self--adjoint operators. These results lead to growth
estimates which provide information on the stability of self--similar wave
maps. Finally, convergence properties of $f_n$ for large $n$ and the spectra of
the corresponding perturbation operators are investigated.
  The thesis is intended to be self--contained as far as possible, i.e. all the
mathematical requirements are carefully introduced, including proofs for many
results which could be found elsewhere.


title:
Some aspects of fractional diffusion equations of single and distributed
  order

abstract:
  The time fractional diffusion equation is obtained from the standard
diffusion equation by replacing the first-order time derivative with a
fractional derivative of order $\beta \in (0,1)$. The fundamental solution for
the Cauchy problem is interpreted as a probability density of a self-similar
non-Markovian stochastic process related to a phenomenon of sub-diffusion (the
variance grows in time sub-linearly). A further generalization is obtained by
considering a continuous or discrete distribution of fractional time
derivatives of order less than one.
  Then the fundamental solution is still a probability density of a
non-Markovian process that, however, is no longer self-similar but exhibits a
corresponding distribution of time-scales.

categories: math-ph cond-mat.dis-nn cond-mat.stat-mech math.MP


title: Toward a quantitative analysis of virus and plasmid trafficking in cells

abstract:
  Intracellular transport of DNA carriers is a fundamental step of gene
delivery. We present here a theoretical approach to study generically a single
virus or DNA particle trafficking in a cell cytoplasm. Cellular trafficking has
been studied experimentally mostly at the macroscopic level, but very little
has been done so far at the microscopic level. We present here a physical model
to account for certain aspects of cellular organization, starting with the
observation that a viral particle trajectory consists of epochs of pure
diffusion and epochs of active transport along microtubules. We define a
general degradation rate to describe the limitations of the delivery of plasmid
or viral particles to the nucleus imposed by various types of direct and
indirect hydrolysis activity inside the cytoplasm. Following a homogenization
procedure, which consists of replacing the switching dynamics by a single
steady state stochastic description, not only can we study the spatio-temporal
dynamics of moving objects in the cytosol, but also estimate the probability
and the mean time to go from the cell membrane to a nuclear pore. Computational
simulations confirm that our model can be used to analyze and interpret viral
trajectories and estimate quantitatively the success of nuclear delivery.


title:
On the Physical Significance of Infra-red Corrections to Inflationary
  Observables

abstract:
  Inflationary observables, like the power spectrum, computed at one- and
higher-order loop level seem to be plagued by large infra-red corrections. In
this short note, we point out that these large infra-red corrections appear
only in quantities which are not directly observable. This is in agreement with
general expectations concerning infra-red effects.


title: Dark energy as a mirage

abstract:
  Motivated by the observed cosmic matter distribution, we present the
following conjecture: due to the formation of voids and opaque structures, the
average matter density on the path of the light from the well-observed objects
changes from Omega_M ~ 1 in the homogeneous early universe to Omega_M ~ 0 in
the clumpy late universe, so that the average expansion rate increases along
our line of sight from EdS expansion Ht ~ 2/3 at high redshifts to free
expansion Ht ~ 1 at low redshifts. To calculate the modified observable
distance-redshift relations, we introduce a generalized Dyer-Roeder method that
allows for two crucial physical properties of the universe: inhomogeneities in
the expansion rate and the growth of the nonlinear structures. By treating the
transition redshift to the void-dominated era as a free parameter, we find a
phenomenological fit to the observations from the CMB anisotropy, the position
of the baryon oscillation peak, the magnitude-redshift relations of type Ia
supernovae, the local Hubble flow and the nucleosynthesis, resulting in a
concordant model of the universe with 90% dark matter, 10% baryons, no dark
energy, 15 Gyr as the age of the universe and a natural value for the
transition redshift z_0=0.35. Unlike a large local void, the model respects the
cosmological principle, further offering an explanation for the late onset of
the perceived acceleration as a consequence of the forming nonlinear
structures. Additional tests, such as quantitative predictions for angular
deviations due to an anisotropic void distribution and a theoretical derivation
of the model, can vindicate or falsify the interpretation that light
propagation in voids is responsible for the perceived acceleration.


title: The multiple quasar Q2237+0305 under a microlensing caustic

abstract:
  We use the high magnification event seen in the 1999 OGLE campaign light
curve of image C of the quadruply imaged gravitational lens Q2237+0305 to study
the structure of the quasar engine. We have obtained g'- and r'-band photometry
at the Apache Point Observatory 3.5m telescope where we find that the event has
a smaller amplitude in the r'-band than in the g'- and OGLE V-bands. By
comparing the light curves with microlensing simulations we obtain constraints
on the sizes of the quasar regions contributing to the g'- and r'-band flux.
Assuming that most of the surface mass density in the central kiloparsec of the
lensing galaxy is due to stars and by modeling the source with a Gaussian
profile, we obtain for the Gaussian width 1.20 x 10^15 sqrt(M/0.1M_sun)cm <
sigma_g' < 7.96 x 10^15 sqrt(M/0.1Msun) cm, where M is the mean microlensing
mass, and a ratio sigma_r'/sigma_g'=1.25^{+0.45}_{-0.15}. With the limits on
the velocity of the lensing galaxy from Gil-Merino et al. (2005) as our only
prior, we obtain 0.60 x 10^15 sqrt(M/0.1Msun) cm < sigma_g' < 1.57 x 10^15
sqrt(M/0.1Msun) cm and a ratio sigma_r'/sigma_g'=1.45^{+0.90}_{-0.25} (all
values at 68 percent confidence). Additionally, from our microlensing
simulations we find that, during the chromatic microlensing event observed, the
continuum emitting region of the quasar crossed a caustic at >72 percent
confidence.


title:
Dispersion Terms and Analysis of Size- Charge Dependence in an Enhanced
  Poisson Boltzmann Approach

abstract:
  We implement a well-established concept to consider dispersion effects within
a Poisson-Boltzmann approach of continuum solvation of proteins. The
theoretical framework is particularly suited for boundary element methods. Free
parameters are determined by comparison to experimental data as well as
high-level quantum mechanical reference calculations. The method is general and
can be easily extended in several directions. The model is tested on various
chemical substances and found to yield good-quality estimates of the solvation
free energy without obvious indication of any introduced bias. Once optimized,
the model is applied to a series of proteins, and factors such as protein size
or partial charge assignments are studied.


title: Extinction properties of lensing galaxies

abstract:
  Context. Observations of quasars shining through foreground galaxies, offer a
way to probe the dust extinction curves of distant galaxies. Interesting
objects for this study are found in strong gravitational lensing systems, where
the foreground galaxies generate multiple images.
  Aims. The reddening law of lensing galaxies is investigated by studying the
colours of gravitationally-lensed quasars, and a handful of other quasars where
a foreground galaxy is detected.
  Methods. We compare the observed colours of quasars reported in the
literature, with spectral templates reddened by different extinction laws and
dust properties. The data consists of 21 quasar-galaxy systems, with a total of
48 images. The galaxies, which are both early- and late-type, have redshifts in
the interval z=0.04-1.51.
  Results. We measure a difference in rest-frame B-V between the quasar images
we study, and quasars without resolved foreground galaxies. This difference in
colour is indicative of significant dust extinction in the intervening galaxy.
Good fits to standard extinction laws were found for 22 of the images,
corresponding to 13 different galaxies. Our fits imply a wide range of possible
values for the total-to-selective extinction ratio, Rv. The distribution was
found to be broad with a weighted mode of Rv=2.4 and a FWHM of 2.7 (sigma =
1.1). Thus the bulk of the galaxies for which good reddening fits could be
derived, have dust properties compatible with the Milky Way value (Rv=3.1).


title: Simple Lie Algebras having Extremal Elements

abstract:
  Let L be a simple finite-dimensional Lie algebra of characteristic distinct
from 2 and from 3. Suppose that L contains an extremal element that is not a
sandwich, that is, an element x such that [x, [x, L]] is equal to the linear
span of x in L. In this paper we prove that, with a single exception, L is
generated by extremal elements. The result is known, at least for most
characteristics, but the proofs in the literature are involved. The current
proof closes a gap in a geometric proof that every simple Lie algebra
containing no sandwiches (that is, ad-nilpotent elements of order 2) is in fact
of classical type.


title:
Signatures of Dynamical Heterogeneity in the Structure of Glassy
  Free-energy Minima

abstract:
  From numerical minimization of a model free energy functional for a system of
hard spheres, we show that the width of the local peaks of the time-averaged
density field at a glassy free-energy minimum exhibits large spatial variation,
similar to that of the ``local Debye-Waller factor'' in simulations of
dynamical heterogeneity. Molecular dynamics simulations starting from a
particle configuration generated from the density distribution at a glassy
free-energy minimum show similar spatial heterogeneity in the degree of
localization, implying a direct connection between dynamical heterogeneity and
the structure of glassy free energy minima.


title: Dynamics of coherent polaritons in double-well systems

abstract:
  We investigate the physics of coherent polaritons in a double-well
configuration under a resonant pumping. For a continuous wave pump, bistability
and self-pulsing regimes are identified as a function of the pump energy and
intensity. The response to an additional probe pulse is characterized in the
different cases and related to the Bogoliubov modes around the stationary
state. Under a pulsed pump, a crossover from Josephson-like oscillations to
self-trapping is predicted for increasing pump intensity. The accurateness of
the effective two-mode model is assessed by comparing its predictions to a full
solution of the non-equilibrium Gross-Pitaevskii equation.


title:
Solution of spin-boson systems in one and two-dimensional geometry via
  the asymptotic iteration method

abstract:
  We consider solutions of the $2\times 2$ matrix Hamiltonian of physical
systems within the context of the asymptotic iteration method. Our technique is
based on transformation of the associated Hamiltonian in the form of the first
order coupled differential equations. We construct a general matrix Hamiltonian
which includes a wide class of physical models. The systematic study presented
here reproduces a number of earlier results in a natural way as well as leading
to new findings. Possible generalizations of the method are also suggested.


title: Casimir effect in 2+1 dimensional noncommutative theories

abstract:
  We study the Dirichlet Casimir effect for a complex scalar field on two
noncommutative spatial coordinates plus a commutative time. To that end, we
introduce Dirichlet-like boundary conditions on a curve contained in the
spatial plane, in such a way that the correct commutative limit can be reached.
We evaluate the resulting Casimir energy for two different curves: (a) Two
parallel lines separated by a distance $L$, and (b) a circle of radius $R$. In
the first case, the resulting Casimir energy agrees exactly with the one
corresponding to the commutative case, regardless of the values of $L$ and of
the noncommutativity scale $\theta$, while for the latter the commutative
behaviour is only recovered when $R >> \sqrt{\theta}$. Outside of that regime,
the dependence of the energy with $R$ is substantially changed due to
noncommutative corrections, becoming regular for $R \to 0$.


title: Non critical holographic models of the thermal phases of QCD

abstract:
  We analyze the thermal phases of a non critical holographic model of QCD. The
model is based on a six dimensional background of $N_c$ non extremal D4 branes
wrapping a spacial circle of radius $R$ and the compactified Euclidean time
direction of radius $\beta=1/T$. We place in this background stacks of $N_f$ D4
and anti-D4 flavor probe branes with a separation distance $L$ at large radial
direction. %The dual theory is a 4+1 dimensional $SU(N_c)$ gauge theory
%compactified on a radius $R$ with anti-periodic boundary conditions for the
fermions. The analysis of the DBI effective action yields the following phase
diagram: At low temperature the system is in a confining phase with broken
chiral symmetry. In the high temperature deconfining phase chiral symmetry can
be either restored for $L>L_c=1.06 R$ or broken for $L<L_c$. All of these phase
transitions are of first order. We analyze the spectrum of the low-spin and
high-spin mesons. High spin mesons above certain critical angular momentum
``melt''. We detect (no) drag for (mesons) quarks moving in hot quark-gluon
fluid. The results resemble the structure and properties of the thermal
Sakai-Sugimoto model derived in hep-th/0604161.


title:
Exciton dephasing in quantum dots: Coupling to LO phonons via excited
  states

abstract:
  We have found a novel mechanism of spectral broadening and dephasing in
quantum dots (QDs) due to the coupling to longitudinal-optical (LO) phonons. In
theory, this mechanism comes into play only if the complete manifold of exciton
levels (including those in the wetting-layer continuum) is taken into account.
We demonstrate this nontrivial dephasing in different types of QDs, using the
exactly solvable quadratic coupling model, here generalized to an arbitrary
number of excitonic states.


title: A Complete Scheme of Ionization Cooling for a Muon Collider

abstract:
  A complete scheme for production and cooling a muon beam for three specified
muon colliders is presented. Parameters for these muon colliders are given. The
scheme starts with the front end of a proposed neutrino factory that yields
bunch trains of both muon signs. Emittance exchange cooling in slow helical
lattices reduces the longitudinal emittance until it becomes possible to merge
the trains into single bunches, one of each sign. Further cooling in all
dimensions is applied to the single bunches in further slow helical lattices.
Final transverse cooling to the required parameters is achieved in 50 T
solenoids using high Tc superconductor at 4 K. Preliminary simulations of each
element are presented.


title: The number of dimensional fundamental constants

abstract:
  We revisit, qualify, and objectively resolve the seemingly controversial
question about what is the number of dimensional fundamental constants in
Nature. For this purpose, we only assume that all we can directly measure are
space and time intervals, and that this is enough to evaluate any physical
observable. We conclude that the number of dimensional fundamental constants is
two. We emphasize that this is an objective result rather than a "philosophical
opinion", and we let it clear how it could be refuted in order to prove us
wrong. Our conclusion coincides with Veneziano's string-theoretical one but our
arguments are not based on any particular theory. As a result, this implies
that one of the three usually considered fundamental constants "G", "c" or "h"
can be eliminated and we show explicitly how this can be accomplished.

categories: physics.class-ph gr-qc hep-th physics.gen-ph


title:
Statistics of charge transfer through impurities in strongly correlated
  1D metals

abstract:
  We review recent advances in the field of full counting statistics (FCS) of
charge transfer through impurities imbedded into strongly correlated
one-dimensional metallic systems, modelled by Tomonaga-Luttinger liquids
(TLLs). We concentrate on the exact analytic solutions for the cumulant
generating function (CGF), which became available recently and apply these
methods in order to obtain the FCS of a non-trivial contact between two crossed
TLL.


title: Gamma-Ray Pulsar Studies with GLAST

abstract:
  Some pulsars have their maximum observable energy output in the gamma-ray
band, offering the possibility of using these high-energy photons as probes of
the particle acceleration and interaction processes in pulsar magnetospheres.
After an extended hiatus between satellite missions, the recently-launched
AGILE mission and the upcoming Gamma-ray Large Area Space Telescope (GLAST)
Large Area Telescope (LAT) will allow gamma-ray tests of the theoretical models
developed based on past discoveries. With its greatly improved sensitivity,
better angular resolution, and larger energy reach than older instruments,
GLAST LAT should detect dozens to hundreds of new gamma-ray pulsars and measure
luminosities, light curves, and phase-resolved spectra with unprecedented
resolution. It will also have the potential to find radio-quiet pulsars like
Geminga, using blind search techniques. Cooperation with radio and X-ray pulsar
astronomers is an important aspect of the LAT team's planning for pulsar
studies.


title:
Correlation-Polarization Effects in Electron/Positron Scattering from
  Acetylene: A Comparison of Computational Models

abstract:
  Different computational methods are employed to evaluate elastic
(rotationally summed) integral and differential cross sections for low energy
(below about 10 eV) positron scattering off gas-phase C$_2$H$_2$ molecules. The
computations are carried out at the static and static-plus-polarization levels
for describing the interaction forces and the correlation-polarization
contributions are found to be an essential component for the correct
description of low-energy cross section behavior. The local model potentials
derived from density functional theory (DFT) and from the distributed positron
model (DPM) are found to produce very high-quality agreement with existing
measurements. On the other hand, the less satisfactory agreement between the
R-matrix (RM) results and measured data shows the effects of the slow
convergence rate of configuration-interaction (CI) expansion methods with
respect to the size of the CI-expansion. To contrast the positron scattering
findings, results for electron-C$_2$H$_2$ integral and differential cross
sections, calculated with both a DFT model potential and the R-matrix method,
are compared and analysed around the shape resonance energy region and found to
produce better internal agreement.


title: Quantum Zeno dynamics and quantum Zeno subspaces

abstract:
  A quantum Zeno dynamics can be obtained by means of frequent measurements,
frequent unitary kicks or a strong continuous coupling and yields a partition
of the total Hilbert space into quantum Zeno subspaces, among which any
transition is hindered. We focus on the "continuous" version of the quantum
Zeno effect and look at several interesting examples. We first analyze these
examples in practical terms, towards applications, then propose a novel
experiment.


title: Study of dielectron production in C+C collisions at 1 AGeV

abstract:
  The emission of e+e- pairs from C+C collisions at an incident energy of 1 GeV
per nucleon has been investigated. The measured production probabilities,
spanning from the pi0-Dalitz to the rho/omega! invariant-mass region, display a
strong excess above the cocktail of standard hadronic sources. The
bombarding-energy dependence of this excess is found to scale like pion
production, rather than like eta production. The data are in good agreement
with results obtained in the former DLS experiment.


title: Experimentally friendly geometrical criteria for entanglement

abstract:
  We present an intuitive geometrical entanglement criterion. It allows
formulation of simple and experimentally friendly sufficient conditions for
entanglement. The conditions are illustrated with several examples. Moreover, a
generalization of our approach is a necessary and sufficient separability
condition. It can be associated with a family of entanglement identifiers,
which is strictly richer than the family of entanglement witnesses.


title:
Thermodynamics and Dynamics of a Monoatomic Glass-Former. Constant
  Pressure and Constant Volume Behavior

abstract:
  We report constant-volume and constant-pressure simulations of the
thermodynamic and dynamic properties of the low-temperature liquid and
crystalline phases of the modified Stillinger-Weber (mSW) model. We have found
an approximately linear increase of the effective Gaussian width of the
distribution of inherent structures. This effect comes from non-Gaussianity of
the landscape and is consistent with the predictions of the Gaussian
excitations model representing the thermodynamics of the configurational
manifold as an ensemble of excitations, each carrying an excitation entropy.
The mSW model provides us with both the configurational and excess entropies,
with the difference mostly attributed to vibrational anharmonicity. We
therefore can address the distinction between the excess thermodynamic
quantities often used in the Adam-Gibbs (AG) equation. We find a new break in
the slope of the constant pressure AG plot when the excess entropy is used in
the AG equation. The simulation diffusivity data are equally well fitted by
applying a new equation, derived within the Gaussian excitations model, that
emphasizes enthalpy over entropy as the thermodynamic control variable for
transport in viscous liquids.


title: Integral Coefficients for One-Loop Amplitudes

abstract:
  We present a set of algebraic functions for evaluating the coefficients of
the scalar integral basis of a general one-loop amplitude. The functions are
derived from unitarity cuts, but the complete cut-integral procedure has been
carried out in generality so that it never needs to be repeated. Where the
master integrals are known explicitly, the results here can be used as a black
box with tree-level amplitudes as input and one-loop amplitudes as output.


title:
Non-linear dynamics and two-dimensional solitons for spin $ S=1$
  ferromagnets with biquadratic exchange

abstract:
  We develop a consistent semiclassical theory of spin dynamics for an
isotropic ferromagnet with a spin $ S=1$ taking into consideration both
bilinear and biquadratic over spin operators exchange interaction. For such
non-Heisenberg magnets, a peculiar class of spin oscillations and waves, for
which the quantum spin expectation value $ {\rm {\bf m}}=<{\rm {\bf S}}>$ does
not change it direction, but changes in length, is presented. Such
``longitudinal'' excitations do not exist in regular magnets, dynamics of which
are described in terms of the Landau-Lifshitz equation or by means of the spin
Heisenberg Hamiltonian. We demonstrate the presence of non-linear uniform
oscillations and waves, as well as self-localized dynamical excitations
(solitons) with finite energy. A possibility of excitation of such oscillations
by ultrafast laser pulse is discussed.


title: Quantum state discrimination: a geometric approach

abstract:
  We analyse the problem of finding sets of quantum states that can be
deterministically discriminated. From a geometric point of view this problem is
equivalent to that of embedding a simplex of points whose distances are maximal
with respect to the Bures distance (or trace distance). We derive upper and
lower bounds for the trace distance and for the fidelity between two quantum
states, which imply bounds for the Bures distance between the unitary orbits of
both states. We thus show that when analysing minimal and maximal distances
between states of fixed spectra it is sufficient to consider diagonal states
only. Hence considering optimal discrimination, given freedom up to unitary
orbits, it is sufficient to consider diagonal states. This is illustrated
geometrically in terms of Weyl chambers.


title: Unipotent classes and special Weyl group representations

abstract:
  We show that various invariants of a unipotent conjugacy class in a connected
semisimple group can be recovered purely in terms of data involving the Weyl
group.


title: Linear and non-Linear Instabilities in Unified Dark Energy Models

abstract:
  We revisit the paradigm of unified dark energy discussing in detail the
averaging problem in this type of scenarios, highlighting the need for a full
non-linear treatment. We also address the question of if and how models with
one or several dark fluids can be observationally distinguished. Simpler and
physically clearer derivations of some key results, most notably on the
relation between the generalized Chaplygin gas and the standard ($\Lambda$CDM)
`concordance' model and on a Jeans-type small-scale instability of some coupled
dark energy/dark matter models are presented.


title:
The role of density stratification in generating zonal flow structures
  in a rotating fluid

abstract:
  Local generation of vorticity occurs in rotating density-stratified fluids as
fluid parcels move radially, expanding or contracting with respect to the
background density stratification. Thermal convection in rotating 2D equatorial
simulations demonstrates this mechanism. The convergence of the vorticity into
zonal flow structures as a function of radius depends on the shape of the
density profile, with the prograde jet forming in the region of the disk where
the greatest number of density scale heights occurs. The number of stable jets
that form in the fluid increases with decreasing Ekman number and decreases
with increasing thermal driving. This local form of vorticity generation via
the density stratification is likely to be of great importance in bodies that
are quickly rotating, highly turbulent, and have large density changes, such as
Jovian planets. However, it is likely to be of lesser importance in the
interiors of planets such as the Earth, which have smaller density
stratifications and are less turbulent.


title: More about QCD on compact spaces

abstract:
  We present some results about spontaneous breaking of global symmetries for
four-flavor, three color QCD on compact spaces with two short directions. When
the two short directions have equal length and identical boundary conditions,
there is a single transition. When the two short directions have boundary
conditions of opposite parity and are of roughly equal extent, the C-breaking
and deconfinement transitions separate. When the two short dimensions are of
different length, the transitions are modified in qualitative agreement with
expectations from dimensional reduction. These features resemble the situation
in pure gauge simulations at small and large number of colors.


title:
Absolute Continuity of the Integrated Density of States for the Almost
  Mathieu Operator with Non-Critical Coupling

abstract:
  We show that the integrated density of states of the almost Mathieu operator
is absolutely continuous if and only if the coupling is non-critical. We deduce
for subcritical coupling that the spectrum is purely absolutely continuous for
almost every phase, settling the measure-theoretical case of Problem 6 of Barry
Simon's list of Schr\"odinger operator problems for the twenty-first century.


title:
Influence of mass multipole moments on the deflection of a light ray by
  an isolated axisymmetric body

abstract:
  Future space astrometry missions are planned to measure positions and/or
parallaxes of celestial objects with an accuracy of the order of the
microarcsecond. At such a level of accuracy, it will be indispensable to take
into account the influence of the mass multipole structure of the giant planets
on the bending of light rays. Within the parametrized post-Newtonian formalism,
we present an algorithmic procedure enabling to determine explicitly this
influence on a light ray connecting two points located at a finite distance.
Then we specialize our formulae in the cases where 1) the light source is
located at space infinity, 2) both the light source and the observer are
located at space infinity. We examine in detail the cases where the unperturbed
ray is in the equatorial plane or in a meridian plane.


title: Randomness, chaos, and structure

abstract:
  We show how a simple scheme of symbolic dynamics distinguishes a chaotic from
a random time series and how it can be used to detect structural relationships
in coupled dynamics. This is relevant for the question at which scale in
complex dynamics regularities and patterns emerge.


title: Quantum dot cascade laser: Arguments in favor

abstract:
  Quantum cascade lasers are recognized as propitious candidates for future
terahertz optoelectronics. Here we demonstrate several definite advantages of
quantum dot cascade structures over quantum well devices, which suffer
fundamental performance limitations owing to continuous carrier spectrum. The
discrete spectrum of quantum dots opens an opportunity to control the
non-radiative relaxation and optical loss and also provides for more
flexibility in the choice of an optical and electrical design of the laser.


title:
Transverse-momentum-dependent parton distribution function in
  soft-collinear effective theory

abstract:
  Transverse-momentum-dependent parton distribution functions are analyzed in
semi-inclusive deep inelastic scattering at low transverse momentum using
soft-collinear effective theory. The transverse-momentum-dependent parton
distribution functions are defined on the lightcone without distorting the
lightcone path nor adding additional soft Wilson lines. In this approach, the
comparison between the integrated and unintegrated parton distribution
functions becomes transparent. The procedure of computing radiative corrections
in dimensional regularization is explained in detail, and the divergence, which
is a product of infrared and ultraviolet divergence, is cancelled. The
renormalization group equation for the transverse-momentum-dependent parton
distribution functions is derived. It depends only on the relevant physical
quantities and exhibits a nontrivial scaling behavior because the longitudinal
momentum fraction and the transverse momentum are coupled in the
renormalization group equation.


title:
Multicritical end-point of the first-order ferromagnetic transition in
  colossal magnetoresistive manganites

abstract:
  We have studied the bandwidth-temperature-magnetic field phase diagram of
RE(0.55)Sr(0.45)MnO(3) colossal magnetoresistance manganites with ferromagnetic
metallic (FM) ground state. The bandwidth (or equivalently the double exchange
interaction) was controlled both via chemical substitution and hydrostatic
pressure with a focus on the vicinity of the critical pressure p* where the
character of the zero-field FM transition changes from first to second order.
Below p* the first-order FM transition extends up to a critical magnetic field,
H_cr. It is suppressed by pressure and approaches zero on the larger bandwidth
side where the surface of the first-order FM phase boundary is terminated by a
multicritical end-point (p*~32 kbar, T*~188 K, H*=0). The change in the
character of the transition and the decrease of the CMR effect is attributed to
the reduced CO/OO fluctuations.


title: A multispectral view of the periodic events in eta Carinae

abstract:
  A full description of the 5.5-yr low excitation events in Eta Carinae is
presented. We show that they are not as simple and brief as previously thought,
but a combination of two components. The first, the 'slow variation' component,
is revealed by slow changes in the ionization level of circumstellar matter
across the whole cycle and is caused by gradual changes in the wind-wind
collision shock-cone orientation, angular opening and gaseous content. The
second, the 'collapse' component, is restricted to around the minimum, and is
due to a temporary global collapse of the wind-wind collision shock. High
energy photons (E > 16 eV) from the companion star are strongly shielded,
leaving the Weigelt objects at low ionization state for >6 months. High energy
phenomena are sensitive only to the 'collapse', low energy only to the 'slow
variation' and intermediate energies to both components. Simple eclipses and
mechanisms effective only near periastron (e.g., shell ejection or accretion
onto the secondary star) cannot account for the whole 5.5-yr cycle.
  We find anti-correlated changes in the intensity and the radial velocity of P
Cygni absorption profiles in FeII 6455 and HeI 7065 lines, indicating that the
former is associated to the primary and the latter to the secondary star. We
present a set of light curves representative of the whole spectrum, useful for
monitoring the next event (2009 January 11).


title: Steering quantum transitions between three crossing energy levels

abstract:
  We calculate the propagator and the transition probabilities for a coherently
driven three-state quantum system. The energies of the three states change
linearly in time, whereas the interactions between them are pulse-shaped. We
derive a highly accurate analytic approximation by assuming independent
pairwise Landau-Zener transitions occurring instantly at the relevant avoided
crossings, and adiabatic evolution elsewhere. Quantum interferences are
identified, which occur due to different possible evolution paths in Hilbert
space between an initial and a final state. A detailed comparison with
numerical results for Gaussian-shaped pulses demonstrates a remarkable accuracy
of the analytic approximation. We use the analytic results to derive estimates
for the half-width of the excitation profile, and for the parameters required
for creation of a maximally coherent superposition of the three states. These
results are of potential interest in ladder climbing in alkali atoms by chirped
laser pulses, in quantum rotors, in transitions between Zeeman sublevels of a
J=1 level in a magnetic field, and in control of entanglement of a pair of
spin-1/2 particles. The results for the three-state system can be generalized,
without essential difficulties, to higher dimensions.


title:
Quantum computers can search rapidly by using almost any selective
  transformations

abstract:
  The search problem is to find a state satisfying certain properties out of a
given set. Grover's algorithm drives a quantum computer from a prepared initial
state to the target state and solves the problem quadratically faster than a
classical computer. The algorithm uses selective transformations to distinguish
the initial state and target state from other states. It does not succeed
unless the selective transformations are very close to phase-inversions. Here
we show a way to go beyond this limitation. An important application lies in
quantum error-correction, where the errors can cause the selective
transformations to deviate from phase-inversions. The algorithms presented here
are robust to errors as long as the errors are reproducible and reversible.
This particular class of systematic errors arise often from imperfections in
apparatus setup. Hence our algorithms offer a significant flexibility in the
physical implementation of quantum search.


title: Reconstruction of scalar potentials in two-field cosmological models

abstract:
  We study the procedure of the reconstruction of phantom-scalar field
potentials in two-field cosmological models. It is shown that while in the
one-field case the chosen cosmological evolution defines uniquely the form of
the scalar potential, in the two-field case one has an infinite number of
possibilities. The classification of a large class of possible potentials is
presented and the dependence of cosmological dynamics on the choice of initial
conditions is investigated qualitatively and numerically for two particular
models.


title:
Spatial amplitude and phase modulation using commercial twisted nematic
  LCDs

abstract:
  We present a method for full spatial phase and amplitude control of a laser
beam using a twisted nematic liquid crystal display combined with a spatial
filter. By spatial filtering we combine four neighboring pixels into one
superpixel. At each superpixel we are able to independently modulate the phase
and the amplitude of light. We demonstrate experimentally the independent phase
and amplitude modulation using this novel technique. Our technique does not
impose special requirements on the spatial light modulator and allows precise
control of fields even with imperfect modulators.


title:
Notes on the Kazhdan-Lusztig theorem on equivalence of the Drinfeld
  category and the category of Uq(g)-modules

abstract:
  We discuss the proof of Kazhdan and Lusztig of the equivalence of the
Drinfeld category D(g,h) of g-modules and the category of finite dimensional
Uq(g)-modules, q=exp(\pi ih), for h\in C\Q*. Aiming at operator algebraists the
result is formulated as the existence for each h\in iR of a normalized unitary
2-cochain F on the dual \hat G of a compact simple Lie group G such that the
convolution algebra of G with the coproduct twisted by F is *-isomorphic to the
convolution algebra of the q-deformation G_q of G, while the coboundary of
F^{-1} coincides with Drinfeld's KZ-associator defined via monodromy of the
Knizhnik-Zamolodchikov equations.


title: More on Non-standard Interaction at MINOS

abstract:
  We discuss about effects of the non-standard interaction of neutrinos with
matter on the nu_e appearance search in the MINOS experiment. We consider the
effects of the complex phase of the interaction and of the uncertainty on
theta_23 also. We show that the oscillation probability can be so large that
can not be explained by the ordinary oscillation. We show also how much
constraints on the non-standard effects can be improved if the experiment does
not observe nu_e appearance signal.


title: Form factors and other measures of strangeness in the nucleon

abstract:
  We discuss the phenomenology of strange-quark dynamics in the nucleon, based
on experimental and theoretical results for electroweak form factors and for
parton densities. In particular, we construct a model for the generalized
parton distribution that relates the asymmetry s(x)-sbar(x) between the
longitudinal momentum distributions of strange quarks and antiquarks with the
form factor F1^s(t), which describes the distribution of strangeness in
transverse position space.


title: 2MTF I. The Tully-Fisher Relation in the 2MASS J, H and K Bands

abstract:
  The 2 Micron All-Sky Survey (2MASS) Tully-Fisher Survey (2MTF) aims to
measure Tully-Fisher (TF) distances to all bright inclined spirals in the 2MASS
Redshift Survey (2MRS). Essential to this project is a universal calibration of
the TF relation in the 2MASS J (1.2 um), H (1.6 um) and K (2.2 um) bands. We
present the first bias corrected or universal TF template in these bands. We
find that the slope of the TF relation becomes steeper as the wavelength
increases being close to L \propto v^4 in K-band and L \propto v^3.6 in J and
H-bands. We also investigate the dependence on galaxy morphology showing that
in all three bands the relation is steeper for later type spirals which also
have a dimmer TF zeropoint than earlier type spirals. We correct the final
relation to that for Sc galaxies. Finally we study the scatter from the TF
relation fitting for a width dependent intrinsic scatter which is not found to
vary significantly with wavelength.


title: Shot Noise in Ballistic Graphene

abstract:
  We have investigated shot noise in graphene field effect devices in the
temperature range of 4.2--30 K at low frequency ($f$ = 600--850 MHz). We find
that for our graphene samples with large width over length ratio $W/L$, the
Fano factor $\mathfrak{F}$ reaches a maximum $\mathfrak{F} \sim$ 1/3 at the
Dirac point and that it decreases strongly with increasing charge density. For
smaller $W/L$, the Fano factor at Dirac point is significantly lower. Our
results are in good agreement with the theory describing that transport at the
Dirac point in clean graphene arises from evanescent electronic states.


title: Generation of Large-Scale Magnetic Fields in Single-Field Inflation

abstract:
  We consider the generation of large-scale magnetic fields in slow-roll
inflation. The inflaton field is described in a supergravity framework where
the conformal invariance of the electromagnetic field is generically and
naturally broken. For each class of inflationary scenarios, we determine the
functional dependence of the gauge coupling that is consistent with the
observations on the magnetic field strength at various astrophysical scales
and, at the same time, avoid a back-reaction problem. Then, we study whether
the required coupling functions can naturally emerge in well-motivated,
possibly string-inspired, models. We argue that this is non trivial and can be
realized only for a restricted class of scenarios. This includes power-law
inflation where the inflaton field is interpreted as a modulus. However, this
scenario seems to be consistent only if the energy scale of inflation is low
and the reheating stage prolonged. Another reasonable possibility appears to be
small field models since no back-reaction problem is present in this case but,
unfortunately, the corresponding scenario cannot be justified in a stringy
framework. Finally, large field models do not lead to sensible model building.


title: N-particle scattering matrix for electrons interacting on a quantum dot

abstract:
  We present a non-perturbative expression for the scattering matrix of $N$
particles interacting inside a quantum dot. Characterizing the dot by its
resonances, we find a compact form for the scattering matrix in a real-time
representation. We study the transmission probabilities and interaction-induced
orbital entanglement of two electrons incident on the dot in a spin-singlet
state.


title: Knowware: the third star after Hardware and Software

abstract:
  This book proposes to separate knowledge from software and to make it a
commodity that is called knowware. The architecture, representation and
function of Knowware are discussed. The principles of knowware engineering and
its three life cycle models: furnace model, crystallization model and spiral
model are proposed and analyzed. Techniques of software/knowware co-engineering
are introduced. A software component whose knowledge is replaced by knowware is
called mixware. An object and component oriented development schema of mixware
is introduced. In particular, the tower model and ladder model for mixware
development are proposed and discussed. Finally, knowledge service and knowware
based Web service are introduced and compared with Web service. In summary,
knowware, software and hardware should be considered as three equally important
underpinnings of IT industry.
  Ruqian Lu is a professor of computer science of the Institute of Mathematics,
Academy of Mathematics and System Sciences. He is a fellow of Chinese Academy
of Sciences. His research interests include artificial intelligence, knowledge
engineering and knowledge based software engineering. He has published more
than 100 papers and 10 books. He has won two first class awards from the
Academia Sinica and a National second class prize from the Ministry of Science
and Technology. He has also won the sixth Hua Loo-keng Mathematics Prize.


title:
Stellar evolution in real time: Period variations in galactic RR Lyr
  stars

abstract:
  The times of maximum brightness collected in the GEOS RR Lyr database allowed
us to trace the period variations of a sample of 123 galactic RRab variables.
These data span a time baseline exceeding 100 years. Clear evidence of period
increases or decreases at constant rates has been found, suggesting
evolutionary effects. The observed rates are slightly larger than those
predicted by theoretical models; moreover, there is an unexpected large
percentage of RRab stars showing a period decrease. The new possibilities
offered by the use of robotic telecopes (TAROTs, REM) and of data from
satellite (CoRoT) are expected to speed up the project to measure stellar
evolution in real time. It is noteworthy that the outlines of this project have
been sketched during several GEOS meetings, where the different knowledge of
amateur and professional astronomers found a very profitable synthesis.


title: Can B(l^p) ever be amenable?

abstract:
  It is known that ${\cal B}(\ell^p)$ is not amenable for $p =1,2,\infty$, but
whether or not ${\cal B}(\ell^p)$ is amenable for $p \in (1,\infty) \setminus
\{2 \}$ is an open problem. We show that, if ${\cal B}(\ell^p)$ is amenable for
$p \in (1,\infty)$, then so are $\ell^\infty({\cal B}(\ell^p))$ and
$\ell^\infty({\cal K}(\ell^p))$. Moreover, if $\ell^\infty({\cal K}(\ell^p))$
is amenable so is $\ell^\infty(\mathbb{I},{\cal K}(E))$ for any index set
$\mathbb I$ and for any infinite-dimensional ${\cal L}^p$-space $E$; in
particular, if $\ell^\infty({\cal K}(\ell^p))$ is amenable for $p \in
(1,\infty)$, then so is $\ell^\infty({\cal K}(\ell^p \oplus \ell^2))$. We show
that $\ell^\infty({\cal K}(\ell^p \oplus \ell^2))$ is not amenable for $p
=1,\infty$, but also that our methods fail us if $p \in (1,\infty)$. Finally,
for $p \in (1,2)$ and a free ultrafilter $\cal U$ over $\posints$, we exhibit a
closed left ideal of $({\cal K}(\ell^p))_{\cal U}$ lacking a right approximate
identity, but enjoying a certain, very weak complementation property.


title: Geometric Scaling at RHIC and LHC

abstract:
  We present a new phenomenological model of the dipole scattering amplitude to
demonstrate that the RHIC data for hadron production in d-Au collisions for all
available rapidities are compatible with geometric scaling, just like the
small-x inclusive DIS data. A detailed comparison with earlier geometric
scaling violating models of the dipole scattering amplitude in terms of an
anomalous dimension gamma is made. In order to establish whether the geometric
scaling violations expected from small-x evolution equations are present in the
data a much larger range in transverse momentum and rapidity must be probed.
Predictions for hadron production in p-Pb and p-p collisions at LHC are given.
We point out that the fall-off of the transverse momentum distribution at LHC
is a sensitive probe of the variation of gamma in a region where x is much
smaller than at RHIC. In this way, the expectation for the rise of gamma from
small-x evolution can be tested.


title: First Observation and Measurement of the Decay K+- -> pi+- e+ e- gamma

abstract:
  Using the full data set of the NA48/2 experiment, the decay K+- -> pi+- e+ e-
gamma is observed for the first time, selecting 120 candidates with 7.3 +- 1.7
estimated background events. With K+- -> pi+- pi0D as normalisation channel,
the branching ratio is determined in a model-independent way to be Br(K+- ->
pi+- e+ e- gamma, m_eegamma > 260 MeV/c^2) = (1.19 +- 0.12_stat +- 0.04_syst) x
10^-8. This measured value and the spectrum of the e+ e- gamma invariant mass
allow a comparison with predictions of Chiral Perturbation Theory.


title: Two-Loop Superstrings VII, Cohomology of Chiral Amplitudes

abstract:
  The relation between superholomorphicity and holomorphicity of chiral
superstring N-point amplitudes for NS bosons on a genus 2 Riemann surface is
shown to be encoded in a hybrid cohomology theory, incorporating elements of
both de Rham and Dolbeault cohomologies. A constructive algorithm is provided
which shows that, for arbitrary N and for each fixed even spin structure, the
hybrid cohomology classes of the chiral amplitudes of the N-point function on a
surface of genus 2 always admit a holomorphic representative. Three key
ingredients in the derivation are a classification of all kinematic invariants
for the N-point function, a new type of 3-point Green's function, and a
recursive construction by monodromies of certain sections of vector bundles
over the moduli space of Riemann surfaces, holomorphic in all but exactly one
or two insertion points.


title: A Simple Baryon Triality Model for Neutrino Masses

abstract:
  We make a simple ansatz for the supersymmetric lepton-number violating Yukawa
couplings, by relating them to the corresponding Higgs Yukawa couplings. This
reduces the free B$_3$ parameters from 36 to 6. We fit these parameters to
solve the solar and atmospheric neutrino anomalies in terms of neutrino
oscillations. The resulting couplings are consistent with the stringent
low-energy bounds. We investigate the resulting LHC collider signals for a stau
LSP scenario.


title: Singular Moduli of Shimura Curves

abstract:
  The $j$-function acts as a parametrization of the classical modular curve.
Its values at complex multiplication (CM) points are called singular moduli and
are algebraic integers. A Shimura curve is a generalization of the modular
curve and, if the Shimura curve has genus 0, a rational parameterizing function
exists and when evaluated at a CM point is again algebraic over $\mathbb{Q}$.
This paper shows that the coordinate maps for the Shimura curves associated to
the quaternion algebras with discriminants 6 and 10 are Borcherds lifts of
vector-valued modular forms. This property is then used to explicitly compute
the rational norms of singular moduli on these curves. This method not only
verifies the conjectural values for the rational CM points, but also provides a
way of algebraically calculating the norms of CM points on these Shimura curves
with arbitrarily large negative discriminant.


title: Sum-free subsets of finite abelian groups of type III

abstract:
  A finite abelian group $G$ of cardinality $n$ is said to be of type III if
every prime divisor of $n$ is congruent to 1 modulo 3. We obtain a
classification theorem for sum-free subsets of largest possible cardinality in
a finite abelian group $G$ of type III. This theorem, when taken together with
known results, gives a complete characterisation of sum-free subsets of the
largest cardinality in any finite abelian group $G$. We supplement this result
with a theorem on the structure of sum-free subsets of cardinality "close" to
the largest possible in a type III abelian group $G$. We then give two
applications of these results. Our first application allows us to write down a
formula for the number of orbits under the natural action of ${\rm Aut}(G)$ on
the set of sum-free subsets of $G$ of the largest cardinality when $G$ is of
the form $({\mathbf{Z}}/m{\mathbf{Z}})^r$, with all prime divisors of $m$
congruent to 1 modulo 3, thereby extending a result of Rhemtulla and Street.
Our second application provides an upper bound for the number of sum-free
subsets of $G$. For finite abelian groups $G$ of type III and with {\em a given
exponent} this bound is substantially better than that implied by the bound for
the number of sum-free subsets in an arbitrary finite abelian group, due to
Green and Ruzsa.


title: Heat transport in ordered harmonic lattices

abstract:
  We consider heat conduction across an ordered oscillator chain with harmonic
interparticle interactions and also onsite harmonic potentials. The onsite
spring constant is the same for all sites excepting the boundary sites. The
chain is connected to Ohmic heat reservoirs at different temperatures. We use
an approach following from a direct solution of the Langevin equations of
motion. This works both in the classical and quantum regimes. In the classical
case we obtain an exact formula for the heat current in the limit of system
size N to infinity. In special cases this reduces to earlier results obtained
by Rieder, Lebowitz and Lieb and by Nakazawa. We also obtain results for the
quantum mechanical case where we study the temperature dependence of the heat
current. We briefly discuss results in higher dimensions.


title: A Hamilton-Jacobi Formalism for Thermodynamics

abstract:
  We show that classical thermodynamics has a formulation in terms of
Hamilton-Jacobi theory, analogous to mechanics. Even though the thermodynamic
variables come in conjugate pairs such as pressure/volume or
temperature/entropy, the phase space is odd-dimensional. For a system with n
thermodynamic degrees of freedom it is (2n+1)-dimensional. The equations of
state of a substance pick out an n-dimensional submanifold. A family of
substances whose equations of state depend on n parameters define a
hypersurface of co-dimension one. This can be described by the vanishing of a
function which plays the role of a Hamiltonian. The ordinary differential
equations (characteristic equations) defined by this function describe a
dynamical system on the hypersurface. Its orbits can be used to reconstruct the
equations of state. The `time' variable associated to this dynamics is related
to, but is not identical to, entropy. After developing this formalism on
well-grounded systems such as the van der Waals gases and the Curie-Weiss
magnets, we derive a Hamilton-Jacobi equation for black hole thermodynamics in
General Relativity. The cosmological constant appears as a constant of
integration in this picture.

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


title: X-Ray Jet Dynamics in a Polar Coronal Hole Region

abstract:
  New XRT observations of the north polar region taken from the X-ray Telescope
(XRT) of the Hinode (Solar-B) spacecraft are used to analyze several time
sequences showing small loop brightenings with a long ray above. We focus on
the recorded transverse displacement of the jet and discuss scenarios to
explain the main features of the events: the relationship with the expected
surface magnetism, the rapid and sudden radial motion, and possibly the
heating, based on the assumption that the jet occurs above a null point of the
coronal magnetic field. We conclude that 3-D reconnection models are needed to
explain the observational details of these events.


title:
Rabi oscillations and excitation trapping in the coherent excitation of
  a mesoscopic frozen Rydberg gas

abstract:
  We demonstrate the coherent excitation of a mesoscopic ensemble of about 100
ultracold atoms to Rydberg states by driving Rabi oscillations from the atomic
ground state. We employ a dedicated beam shaping and optical pumping scheme to
compensate for the small transition matrix element. We study the excitation in
a weakly interacting regime and in the regime of strong interactions. When
increasing the interaction strength by pair state resonances we observe an
increased excitation rate through coupling to high angular momentum states.
This effect is in contrast to the proposed and previously observed
interaction-induced suppression of excitation, the so-called dipole blockade.


title: Group Bundle Duality

abstract:
  This paper introduces a generalization of Pontryagin duality for locally
compact Hausdorff abelian groups to locally compact Hausdorff abelian group
bundles.


title:
Quantum oscillations of rectified dc voltage as a function of magnetic
  field in an "almost" symmetric superconducting ring

abstract:
  Periodic quantum oscillations of a rectified dc voltage Vdc(B) vs the
perpendicular magnetic field B were measured near the critical temperature Tc
in a single superconducting aluminum almost symmetric ring (without specially
created circular asymmetry) biased by alternating current with a zero dc
component. With varying bias current and temperature, these Vdc(B) oscillations
behave like the Vdc(B) oscillations observed in a circular-asymmetric ring but
are of smaller amplitude. The Fourier spectra of the Vdc(B) functions exhibit a
fundamental frequency, corresponding to the ring area, and its higher
harmonics. Unexpectedly, satellite frequencies depending on the structure
geometry and external parameters were found next to the fundamental frequency
and around its higher harmonics.


title: Report on "American Option Pricing and Hedging Strategies"

abstract:
  This paper mainly discusses the American option's hedging strategies via
binomialmodel and the basic idea of pricing and hedging American option.
Although the essential scheme of hedging is almost the same as European option,
small differences may arise when simulating the process for American option
holder has more rights, spelling that the option can be exercised at anytime
before its maturity. Our method is dynamic-hedging method.


title: On Three Different Notions of Monotone Subsequences

abstract:
  We review how the monotone pattern compares to other patterns in terms of
enumerative results on pattern avoiding permutations. We consider three natural
definitions of pattern avoidance, give an overview of classic and recent
formulas, and provide some new results related to limiting distributions.


title: Inflation in DBI models with constant gamma

abstract:
  Dirac-Born-Infeld scalar field theories which appear in the context of
inflation in string theory in general have a field dependent speed of sound. It
is however possible to write down DBI models which possess exact solutions
characterized by a constant speed of sound different from unity. This requires
that the potential and the effective D-brane tension appearing in a DBI action
have to be related in a specific way. This paper describes such models in
general and presents some examples with a constant speed of sound $c_s<1$ for
which the spectrum of scalar perturbations can be found analytically without
resorting to the slow roll approximation.


title: Integrability of the Gibbons--Tsarev system

abstract:
  A new approach extracting multi-parametric hydrodynamic reductions for the
integrable hydrodynamic chains is presented. The Benney hydrodynamic chain is
considered.


title: Black Holes: Fermions at the Extremal Limit?

abstract:
  I present exact results matching Kerr-Newman Black Hole thermodynamics in the
extremal limit to the two-dimensional Fermi Gas. Two dimensions are consistent
with the membrane paradigm of black holes. Key in the analysis is the
thermodynamic Riemannian curvature scalar $R$, negative for most ordinary
thermodynamic systems, including those near the critical point, but mostly
positive for the Kerr-Newman Black Hole and the Fermi Gas.


title:
When does the choice of the refractive index of a linear, homogeneous,
  isotropic, active, dielectric medium matter?

abstract:
  Two choices are possible for the refractive index of a linear, homogeneous,
isotropic, active, dielectric material. Either of the choices is adequate for
obtaining frequency-domain solutions for (i) scattering by slabs, spheres, and
other objects of bounded extent; (ii) guided-wave propagation in homogeneously
filled, cross-sectionally uniform, straight waveguide sections with perfectly
conducting walls; and (iii) image formation due to flat lenses. The correct
choice does matter for the half-space problem, but that problem is not
realistic.


title: Balanced right/left-handed mixtures of quasi-planar chiral inclusions

abstract:
  Some novel quasi-planar chiral inclusions, feasible from standard
photo-etching techniques, are proposed. It is shown that such inclusions can be
designed in order to present balanced electric, magnetic and magneto-electric
polarizabilities. Using these inclusions, random and periodic bi-isotropic
artificial metamaterials exhibiting a balanced positive/negative refractive
index can be build up. These metamaterials would exhibit reasonable bandwidths
and excellent matching to free space.


title:
Existence and Uniqueness of constant mean curvature foliation of
  asymptotically hyperbolic 3-manifolds II

abstract:
  In a previous paper, the authors showed that metrics which are asymptotic to
Anti-de Sitter-Schwarzschild metrics with positive mass admit a unique
foliation by stable spheres with constant mean curvature. In this paper we
extend that result to all asymptotically hyperbolic metrics for which the trace
of the mass term is positive. We do this by combining the Kazdan-Warner
obstructions with a theorem due to De Lellis and M\"uller.


title: Cross sections for short pulse single and double ionization of helium

abstract:
  In a previous publication, procedures were proposed for unambiguously
extracting amplitudes for single and double ionization from a time-dependent
wavepacket by effectively propagating for an infinite time following a
radiation pulse. Here we demonstrate the accuracy and utility of those methods
for describing two-photon single and one-photon double ionization of helium. In
particular it is shown how narrow features corresponding to autoionizing states
are easily resolved with these methods.


title: Chiral Decomposition in the Electronic Structure of Graphene Multilayers

abstract:
  We show that the low-energy electronic structure of arbitrarily stacked
graphene multilayers with nearest-neighbor interlayer tunneling consists of
chiral pseudospin doublets. Although the number of doublets in an $N$-layer
system depends on the stacking sequence, the pseudospin chirality sum is always
$N$. $N$-layer stacks have $N$ distinct Landau levels at E=0 for each spin and
valley, and quantized Hall conductivity $\sigma_{xy} = \pm(4 e^2/h)(N/2+n)$
where $n$ is a non-negative integer.


title: Merged ionization/dissociation fronts in planetary nebulae

abstract:
  The hydrogen ionization and dissociation front around an ultraviolet
radiation source should merge when the ratio of ionizing photon flux to gas
density is sufficiently low and the spectrum is sufficiently hard. This regime
is particularly relevant to the molecular knots that are commonly found in
evolved planetary nebulae, such as the Helix Nebula, where traditional models
of photodissociation regions have proved unable to explain the high observed
luminosity in H_2 lines. In this paper we present results for the structure and
steady-state dynamics of such advection-dominated merged fronts, calculated
using the Cloudy plasma/molecular physics code. We find that the principal
destruction processes for H_2 are photoionization by extreme ultraviolet
radiation and charge exchange reactions with protons, both of which form H_2^+,
which rapidly combines with free electrons to undergo dissociative
recombination. Advection moves the dissociation front to lower column densities
than in the static case, which vastly increases the heating in the partially
molecular gas due to photoionization of He^0, H_2, and H^0. This causes a
significant fraction of the incident bolometric flux to be re-radiated as
thermally excited infrared H_2 lines, with the lower excitation pure rotational
lines arising in 1000 K gas and higher excitation H_2 lines arising in 2000 K
gas, as is required to explain the H_2 spectrum of the Helix cometary knots.


title:
Insufficient convergence of inverse mean curvature flow on
  asymptotically hyperbolic manifolds

abstract:
  We construct a solution to inverse mean curvature flow on an asymptotically
hyperbolic 3-manifold which does not have the convergence properties needed in
order to prove a Penrose--type inequality. This contrasts sharply with the
asymptotically flat case. The main idea consists in combining inverse mean
curvature flow with work done by Shi--Tam regarding boundary behavior of
compact manifolds. Assuming the Penrose inequality holds, we also derive a
nontrivial inequality for functions on $S^2$.


title:
The real loci of Calogero-Moser spaces, representations of rational
  Cherednik algebras and the Shapiro conjecture

abstract:
  We prove a criterion for the reality of irreducible representations of the
rational Cherednik algebras H_{0,1}(S_n). This is shown to imply a criterion
for the real loci of the Calogero-Moser spaces C_n in terms of the
Etingof-Ginzburg finite maps \Upsilon \colon C_n \to C^n/S_n \times C^n/S_n,
recovering a result of Mikhin, Tarasov, and Varchenko [MTV2]. As a consequence
we obtain a criterion for the real locus of the Wilson's adelic Grassmannian of
rank one bispectral solutions of the KP hierarchy. Using Wilson's first
parametrisation of the adelic Grassmannian, we give a new proof of a result of
[MTV2] on real bases of spaces of quasi polynomials. The Shapiro Conjecture for
Grassmannians is equivalent to a special case of our result for Calogero-Moser
spaces, namely for the fibres of \Upsilon over C^n/S_n \times 0.


title: Intersection form, laminations and currents on free groups

abstract:
  Let $F_N$ be a free group of rank $N\ge 2$, let $\mu$ be a geodesic current
on $F_N$ and let $T$ be an $\mathbb R$-tree with a very small isometric action
of $F_N$. We prove that the geometric intersection number $<T, \mu>$ is equal
to zero if and only if the support of $\mu$ is contained in the dual algebraic
lamination $L^2(T)$ of $T$. Applying this result, we obtain a generalization of
a theorem of Francaviglia regarding length spectrum compactness for currents
with full support. As another application, we define the notion of a
\emph{filling} element in $F_N$ and prove that filling elements are "nearly
generic" in $F_N$. We also apply our results to the notion of \emph{bounded
translation equivalence} in free groups.


title:
Low-energy subgap states and the magnetic flux periodicity in d-wave
  superconducting rings

abstract:
  Wave functions of low-energy quasiparticle subgap states in d-wave
superconducting rings, threaded by Aharonov-Bohm magnetic flux, are found
analytically. The respective energies are closest to the midgap position at
small magnetic fluxes and deviate from the Fermi surface due to the Doppler
shift, produced by the supercurrent. The Doppler-shifted zero-energy states
result in a paramagnetic response of the ring at small fluxes. The states exist
only for even angular momenta of the center of mass of Cooper pairs, in
agreement with recent numerical studies of the problem. This macroscopic
quantum effect in d-wave rings results in broken h/2e periodicity, retaining
only the h/e periodic behavior of the supercurrent with varying magnetic flux.


title:
The nature of highly anisotropic free-electron-like states in a
  glycinate monolayer on Cu(100)

abstract:
  The free-electron-like state observed in a scanning tunneling spectroscopy
study of a chiral p(2x4) monolayer of glycinate ions on the Cu(100) surface [K.
Kanazawa et al, J. Am. Chem. Soc. 129, 740 (2007)] is shown from density
functional theory calculations to originate from a Cu Shockley surface state at
the surface Brillouin zone boundary of the clean surface with highly
anisotropic dispersion. The presence of the glycinate ions on the surface
causes a dramatically enhanced tunneling into this surface state that is
otherwise not observed in tunneling on the bare surface.


title: An Identity on SU(2) Invariants

abstract:
  We prove an identity [Eq. (1) below] among SU(2) 6j and 9j symbols that
generalizes the Biedenharn-Elliott sum rule. We prove the result using
diagrammatic techniques (briefly reviewed here), and then provide an algebraic
proof. This identity is useful for studying meson-baryon scattering in which an
extra isoscalar meson is produced.


title: Translating solutions to Lagrangian mean curvature flow

abstract:
  We prove some non-existence theorems for translating solutions to Lagrangian
mean curvature flow. More precisely, we show that translating solutions with an
$L^2$ bound on the mean curvature are planes and that almost-calibrated
translating solutions which are static are also planes. Recent work of D.
Joyce, Y.-I. Lee, and M.-P. Tsui, shows that these conditions are optimal.


title:
Thermodynamics and Relativity: A Message to Physics Teachers (for an
  easier understanding of the thermodynamic theory)

abstract:
  Whoever has to learn or to teach thermodynamics is confronted with conceptual
difficulties which are specific to this field of physics ([1],[2]). It seems
that they can be eliminated by inserting relativity in the thermodynamic
theory. The aim of this paper is to summarize the problem and draw attention
upon a fundamental point of the discussion.


title: Perfect domination in regular grid graphs

abstract:
  We show there is an uncountable number of parallel total perfect codes in the
integer lattice graph ${\Lambda}$ of $\R^2$. In contrast, there is just one
1-perfect code in ${\Lambda}$ and one total perfect code in ${\Lambda}$
restricting to total perfect codes of rectangular grid graphs (yielding an
asymmetric, Penrose, tiling of the plane). We characterize all cycle products
$C_m\times C_n$ with parallel total perfect codes, and the $d$-perfect and
total perfect code partitions of ${\Lambda}$ and $C_m\times C_n$, the former
having as quotient graph the undirected Cayley graphs of $\Z_{2d^2+2d+1}$ with
generator set $\{1,2d^2\}$. For $r>1$, generalization for 1-perfect codes is
provided in the integer lattice of $\R^r$ and in the products of $r$ cycles,
with partition quotient graph $K_{2r+1}$ taken as the undirected Cayley graph
of $\Z_{2r+1}$ with generator set $\{1,...,r\}$.


title: DNA duplex cage structures with icosahedral symmetry

abstract:
  A construction method for duplex cage structures with icosahedral sym- metry
made out of single-stranded DNA molecules is presented and applied to an
icosidodecahedral cage. It is shown via a mixture of analytic and computer
techniques that there exist realisations of this graph in terms of two circular
DNA molecules. These blueprints for the organisation of a cage structure with a
noncrystallographic symmetry may assist in the design of containers made from
DNA for applications in nanotechnology.


title: Perfect domination in rectangular grid graphs

abstract:
  A dominating set $S$ in a graph $G$ is said to be perfect if every vertex of
$G$ not in $S$ is adjacent to just one vertex of $S$. Given a vertex subset
$S'$ of a side $P_m$ of an $m\times n$ grid graph $G$, the perfect dominating
sets $S$ in $G$ with $S'=S\cap V(P_m)$ can be determined via an exhaustive
algorithm $\Theta$ of running time $O(2^{m+n})$. Extending $\Theta$ to infinite
grid graphs of width $m-1$, periodicity makes the binary decision tree of
$\Theta$ prunable into a finite threaded tree, a closed walk of which yields
all such sets $S$. The graphs induced by the complements of such sets $S$ can
be codified by arrays of ordered pairs of positive integers via $\Theta$, for
the growth and determination of which a speedier %greedy algorithm exists. %and
their periodic structure, further studied. A recent characterization of grid
graphs having total perfect codes $S$ (with just 1-cubes as induced
components), due to Klostermeyer and Goldwasser, is given in terms of $\Theta$,
which allows to show that these sets $S$ are restrictions of only one total
perfect code $S_1$ in the integer lattice graph ${\Lambda}$ of $\R^2$.
Moreover, the complement ${\Lambda}-S_1$ yields an aperiodic tiling, like the
Penrose tiling. In contrast, the parallel, horizontal, total perfect codes in
${\Lambda}$ are in 1-1 correspondence with the doubly infinite
$\{0,1\}$-sequences.


title: Cohomology and Duality for (phi,Gamma)-modules over the Robba ring

abstract:
  Given a p-adic representation of the Galois group of a local field, we show
that its Galois cohomology can be computed using the associated etale
(phi,Gamma)-module over the Robba ring; this is a variant of a result of Herr.
We then establish analogues, for not necessarily etale (phi,Gamma)-modules over
the Robba ring, of the Euler-Poincare characteristic formula and Tate local
duality for p-adic representations. These results are expected to intervene in
the duality theory for Selmer groups associated to de Rham representations.


title:
On fixed point sets of distinguished collections for groups of parabolic
  characteristic

abstract:
  We determine the nature of the fixed point sets of groups of order p, acting
on complexes of distinguished p-subgroups (those p-subgroups containing
p-central elements in their centers). The case when G has parabolic
characteristic p is analyzed in detail.