title:
The VLT-FLAMES survey of massive stars: rotation and nitrogen enrichment
  as the key to understanding massive star evolution

abstract:
  Rotation has become an important element in evolutionary models of massive
stars, specifically via the prediction of rotational mixing. Here, we study a
sample of stars, including rapid rotators, to constrain such models and use
nitrogen enrichments as a probe of the mixing process. Chemical compositions
(C, N, O, Mg and Si) have been estimated for 135 early B-type stars in the
Large Magellanic Cloud with projected rotational velocities up to ~300km/s
using a non-LTE TLUSTY model atmosphere grid. Evolutionary models, including
rotational mixing, have been generated attempting to reproduce these
observations by adjusting the overshooting and rotational mixing parameters and
produce reasonable agreement with 60% of our core hydrogen burning sample. We
find (excluding known binaries) a significant population of highly nitrogen
enriched intrinsic slow rotators vsini less than 50km/s incompatible with our
models ~20% of the sample). Furthermore, while we find fast rotators with
enrichments in agreement with the models, the observation of evolved (log g
less than 3.7dex) fast rotators that are relatively unenriched (a further ~20%
of the sample) challenges the concept of rotational mixing. We also find that
70% of our blue supergiant sample cannot have evolved directly from the
hydrogen burning main-sequence. We are left with a picture where invoking
binarity and perhaps fossil magnetic fields are required to understand the
surface properties of a population of massive main sequence stars.


title: Multipartite entangled states in particle mixing

abstract:
  In the physics of flavor mixing, the flavor states are given by
superpositions of mass eigenstates. By using the occupation number to define a
multiqubit space, the flavor states can be interpreted as multipartite
mode-entangled states. By exploiting a suitable global measure of entanglement,
based on the entropies related to all possible bipartitions of the system, we
analyze the correlation properties of such states in the instances of three-
and four-flavor mixing. Depending on the mixing parameters, and, in particular,
on the values taken by the free phases, responsible for the CP-violation,
entanglement concentrates in preferred bipartitions. We quantify in detail the
amount and the distribution of entanglement in the physically relevant cases of
flavor mixing in quark and neutrino systems. By using the wave packet
description for localized particles, we use the global measure of entanglement,
suitably adapted for the instance of multipartite mixed states, to analyze the
decoherence induced by the free evolution dynamics on the quantum correlations
of stationary neutrino beams. We define a decoherence length as the distance
associated with the vanishing of the coherent interference effects among
massive neutrino states. We investigate the role of the CP-violating phase in
the decoherence process.


title: Gradients of Laplacian Eigenfunctions on the Sierpinski Gasket

abstract:
  We use spectral decimation to provide formulae for computing the harmonic
gradients of Laplacian eigenfunctions on the Sierpinski Gasket. These formulae
are given in terms of special functions that are defined as infinite products.


title: Can a Computer Laugh ?

abstract:
  A computer model of "a sense of humour" suggested previously
[arXiv:0711.2058,0711.2061], relating the humorous effect with a specific
malfunction in information processing, is given in somewhat different
exposition. Psychological aspects of humour are elaborated more thoroughly. The
mechanism of laughter is formulated on the more general level. Detailed
discussion is presented for the higher levels of information processing, which
are responsible for a perception of complex samples of humour. Development of a
sense of humour in the process of evolution is discussed.


title: A quantum Goldman bracket in 2+1 quantum gravity

abstract:
  In the context of quantum gravity for spacetimes of dimension 2+1, we
describe progress in the construction of a quantum Goldman bracket for
intersecting loops on surfaces. Using piecewise linear paths in R^2
(representing loops on the spatial manifold, i.e. the torus) and a quantum
connection with noncommuting components, we review how holonomies and Wilson
loops for two homotopic paths are related by phases in terms of the signed area
between them. Paths rerouted at intersection points with other paths occur on
the r.h.s. of the Goldman bracket. To better understand their nature we
introduce the concept of integer points inside the parallelogram spanned by two
intersecting paths, and show that the rerouted paths must necessarily pass
through these integer points.


title: Tensor calculus for supergravity on a manifold with boundary

abstract:
  Using the simple setting of 3D N=1 supergravity, we show how the tensor
calculus of supergravity can be extended to manifolds with boundary. We present
an extension of the standard F-density formula which yields supersymmetric
bulk-plus-boundary actions. To construct additional separately supersymmetric
boundary actions, we decompose bulk supergravity and bulk matter multiplets
into co-dimension one submultiplets. As an illustration we obtain the
supersymmetric extension of the York-Gibbons-Hawking extrinsic curvature
boundary term. We emphasize that our construction does not require any boundary
conditions on off-shell fields. This gives a significant improvement over the
existing orbifold supergravity tensor calculus.


title:
Energy and System Size Dependence of Strangeness Production from SPS to
  RHIC

abstract:
  Strange particle production is an important experimental observable that
allows the study of the strongly interacting matter created in relativistic
heavy-ion collisions. The STAR experiment at RHIC has a unique capability of
measuring identified strange particles over a wide range of acceptance
providing a rich set of data to perform a systematic study. In addition to the
data from Au+Au collisions, strange particles from p+p and d+Au collisions are
also available for comparison and normalization. A new set of data from Cu+Cu
reactions at 62 GeV and 200 GeV provides the chance to compare the system size
dependence observed in Au+Au collisions with this smaller system size. In
addition to the comparison of the yields, a statistical thermal model was used
to extract freeze-out characteristics for the different system sizes and
collision energies.


title: de Sitter Relativity: a New Road to Quantum Gravity?

abstract:
  The Poincare' group generalizes the Galilei group for high-velocity
kinematics. The de Sitter group is assumed to go one step further, generalizing
Poincare' as the group governing high-energy kinematics. In other words,
ordinary special relativity is here replaced by de Sitter relativity. In this
theory, the cosmological constant is no longer a free parameter, and can be
determined in terms of other quantities. When applied to the whole universe, it
is able to predict the value of the cosmological constant and to explain the
cosmic coincidence. When applied to the propagation of ultra-high energy
photons, it gives a good estimate of the time delay observed in extragalactic
gamma-ray flares. It can, for this reason, be considered a new paradigm to
approach the quantum gravity problem.


title: Scalar mesons from an effective Lagrangian approach

abstract:
  A brief discussion of the recent interest in light scalar mesons motivates
the study of a generalized linear sigma model. In an SU(3) flavor invariant
version of the model there is a prediction that the the lighter scalars have
sizeable "four quark" content. It is further predicted that one of the singlet
scalars should be exceptionally light. Due to the presence of scalar mesons,
the model gives "controlled" corrections to the current algebra formula for
threshold pion pion scattering. These corections act in the direction to
improve agreement with current experiments.


title: Fermion-fermion and boson-boson amplitudes: surprising similarities

abstract:
  Amplitudes for fermion-fermion, boson-boson and fermion-boson interactions
are calculated in the second order of perturbation theory in the Lobachevsky
space. An essential ingredient of the model is the Weinberg's 2(2j+1)-component
formalism for describing a particle of spin j. The boson-boson amplitude is
then compared with the two-fermion amplitude obtained long ago by Skachkov on
the basis of the Hamiltonian formulation of quantum field theory on the mass
hyperboloid, p_0^2 - p^2=M^2, proposed by Kadyshevsky. The parametrization of
the amplitudes by means of the momentum transfer in the Lobachevsky space leads
to same spin structures in the expressions of T-matrices for the fermion case
and the boson case. However, certain differences are found. Possible physical
applications are discussed.


title: Correlating prompt GRB photons with neutrinos

abstract:
  It is standard in theoretical neutrino astrophysics to use a broken power law
approximation, based on the Band function, to describe the average photon flux
of the prompt emission of Gamma-Ray Bursts. We will show that this
approximation overestimates the contribution of high energy gamma-rays (and
underestimates low energy gamma-rays). As a consequence models that rely on
this approximation overestimate neutrino event rate by a factor of approx 2
depending on Earth's column density in the direction of the GRB. Furthermore
the characteristic energy of neutrinos that trigger a km^3 detector is
typically 10^{16} eV, higher than previously predicted. We also provide a new
broken power law approximation to the Band function and show that it properly
represents the photon spectra.


title:
Antisymmetric Tensor Fields, 4-Vector Fields, Indefinite Metrics and
  Normalization

abstract:
  On the basis of our recent modifications of the Dirac formalism we generalize
the Bargmann-Wigner formalism for higher spins to be compatible with other
formalisms for bosons. Relations with dual electrodynamics, with the
Ogievetskii-Polubarinov notoph and the Weinberg 2(2J+1) theory are found. Next,
we introduce the dual analogues of the Riemann tensor and derive corresponding
dynamical equations in the Minkowski space. Relations with the Marques-Spehler
chiral gravity theory are discussed. The problem of indefinite metrics,
particularly, in quantization of 4-vector fields is clarified.


title:
Developments in Black Hole Research: Classical, Semi-classical, and
  Quantum

abstract:
  The possible existence of black holes has fascinated scientists at least
since Michell and Laplace's proposal that a gravitating object could exist from
which light could not escape. In the 20th century, in light of the general
theory of relativity, it became apparent that, were such objects to exist,
their structure would be far richer than originally imagined. Today,
astronomical observations strongly suggest that either black holes, or objects
with similar properties, not only exist but may well be abundant in our
universe. In light of this, black hole research is now not only motivated by
the fascinating theoretical properties such objects must possess but also as an
attempt to better understand the universe around us. We review here some
selected developments in black hole research, from a review of its early
history to current topics in black hole physics research. Black holes have been
studied at all levels; classically, semi-classically, and more recently, as an
arena to test predictions of candidate theories of quantum gravity. We will
review here progress and current research at all these levels as well as
discuss some proposed alternatives to black holes.


title: Properties of quark gluon plasma from lattice calculations

abstract:
  I discuss lattice QCD calculations of the properties of strongly interacting
matter at finite temperature, including the determination of the transition
temperature Tc, equation of state, different static screening lengths and
quarkonium spectral functions. The lattice data suggest that at temperatures
above 2Tc many properties of the quark gluon plasma can be understood using
weak coupling approach, although non-perturbative effects due to static
magnetic fields are significant in some quantities.


title:
High-excitation OH and H_2O lines in Markarian 231: the molecular
  signatures of compact far-infrared continuum sources

abstract:
  The ISO/LWS far-infrared spectrum of the ultraluminous galaxy Mkn 231 shows
OH and H_2O lines in absorption from energy levels up to 300 K above the ground
state, and emission in the [O I] 63 micron and [C II] 158 micron lines. Our
analysis shows that OH and H_2O are radiatively pumped by the far-infrared
continuum emission of the galaxy. The absorptions in the high-excitation lines
require high far-infrared radiation densities, allowing us to constrain the
properties of the underlying continuum source. The bulk of the far-infrared
continuum arises from a warm (T_dust=70-100 K), optically thick
(tau_100micron=1-2) medium of effective diameter 200-400 pc. In our best-fit
model of total luminosity L_IR, the observed OH and H2O high-lying lines arise
from a luminous (L/L_IR~0.56) region with radius ~100 pc. The high surface
brightness of this component suggests that its infrared emission is dominated
by the AGN. The derived column densities N(OH)>~10^{17} cm^{-2} and
N(H_2O)>~6x10^{16} cm^{-2} may indicate XDR chemistry, although significant
starburst chemistry cannot be ruled out. The lower-lying OH, [C II] 158 micron,
and [O I] 63 micron lines arise from a more extended (~350 pc) starburst
region. We show that the [C II] deficit in Mkn 231 is compatible with a high
average abundance of C+ because of an extreme overall luminosity to gas mass
ratio. Therefore, a [C II] deficit may indicate a significant contribution to
the luminosity by an AGN, and/or by extremely efficient star formation.


title: Ultra High Energy Cosmic Rays: origin and propagation

abstract:
  We discuss the basic difficulties in understanding the origin of the highest
energy particles in the Universe - the ultrahigh energy cosmic rays (UHECR). It
is difficult to imagine the sources they are accelerated in. Because of the
strong attenuation of UHECR on their propagation from the sources to us these
sources should be at cosmologically short distance from us but are currently
not identified. We also give information of the most recent experimental
results including the ones reported at this conference and compare them to
models of the UHECR origin.


title:
Possible Coexistence of Antihydrogen with Hydrogen, Deuterium and
  Tritium Atoms

abstract:
  Recent productions of large numbers of cold antiprotons as well as the
formation of antihydrogens at CERN and Fermilab have raised basic questions
about possible coexistence of matter and antimatter in nature. In the present
work, previous mathematical considerations are revisited which support the
possible coexistence of Antihydrogen with Hydrogen, Deuterium and Tritium
atoms. In particular, the main objective of the present work is to present
computational treatments which confirm the possible formation of these quasi
molecules in laboratory. These treatments are based on a nonadiabatic picture
of the system in which generalized basis functions are adjusted within the
framework of Rayleigh-Ritz' variational method. Thus, it is ruled out in the
present work the Born-Oppenheimer adiabatic picture of the system, which
demands the existence of bound states composed of fixed quasi heavy atoms
(containing at least two baryons, e.g. protonium (Pn), with mean lifetime
1.0x10^^-6 s) and quasi light atoms (composed of two leptons, e.g. positronium
(Ps), with mean lifetime 125x10^^-12 s for para-Ps and 142.05x10^^-9 s for
ortho-Ps). Our calculations of the binding energies and internal structure of
Antihydrogen-Hydrogen, Antihydrogen-Deuterium and Antihydrogen-Tritium show
that these quasi molecules are bound and could be formed in nature. On the
other hand, having in mind the adiabatic picture of the systems, our results
suggest the possible formation of these molecules as resonant states in
Antihydrogen-Atom interaction. Nevertheless, several arguments are accumulated
in the conclusion as consequences of the proposed bound states.


title:
Numerical simulations of possible finite time singularities in the
  incompressible Euler equations: comparison of numerical methods

abstract:
  The numerical simulation of the 3D incompressible Euler equation is analyzed
with respect to different integration methods. The numerical schemes we
considered include spectral methods with different strategies for dealiasing
and two variants of finite difference methods. Based on this comparison, a
Kida-Pelz like initial condition is integrated using adaptive mesh refinement
and estimates on the necessary numerical resolution are given. This estimate is
based on analyzing the scaling behavior similar to the procedure in critical
phenomena and present simulations are put into perspective.


title:
Impact on $\gamma\phi_3$ from CLEO-c Using CP-tagged $D\toK_{S,L}\pi\pi$
  Decays

abstract:
  Precision determination of the CKM angle $\gamma/\phi_3$ depends upon
constraints on charm mixing amplitudes, measurements of doubly-Cabibbo
suppressed amplitudes and relative phases, and studies of charm Dalitz plots
tagged by flavor or CP eigenstates. In this note we describe the technique used
at CLEO-c to constrain the $K_{S,L}\pi\pi$ model uncertainty, and its impact on
$\gamma/\phi_3$ measurements at B-factories presented at the Charm 2007
Workshop.


title:
The Aizenman-Sims-Starr scheme for the SK model with multidimensional
  spins

abstract: This paper has been temporarily withdrawn for revision by the authors.


title: Correlation diagrams in collisions of three identical particles

abstract:
  We discuss collision of three identical particles and derive scattering
selection rules from initial to final states of the particles. We use either
laboratory-frame, hyperspherical, or Jacobian coordinates depending on which
one is best suited to describe three different configurations of the particles:
(1) three free particles, (2) a quasi-bound trimer, or (3) a dimer and a free
particle. We summarize quantum numbers conserved during the collision as well
as quantum numbers that are appropriate for a given configuration but may
change during the scattering process. The total symmetry of the system depends
on these quantum numbers. Based on the selection rules, we construct
correlation diagrams between different configurations before and after a
collision. In particular, we describe a possible recombination of the system
into one free particle and a dimer, which can be used, for example, to identify
possible decay products of quasi-stationary three-body states


title: Detection of Contact Binaries Using Sparse High Phase Angle Lightcurves

abstract:
  We show that candidate contact binary asteroids can be efficiently identified
from sparsely sampled photometry taken at phase angles >60deg. At high phase
angle, close/contact binary systems produce distinctive lightcurves that spend
most of the time at maximum or minimum (typically >1mag apart) brightness with
relatively fast transitions between the two. This means that a few (~5) sparse
observations will suffice to measure the large range of variation and identify
candidate contact binary systems. This finding can be used in the context of
all-sky surveys to constrain the fraction of contact binary near-Earth objects.
High phase angle lightcurve data can also reveal the absolute sense of the
spin.


title: Accurate calculation of resonances in multiple-well oscillators

abstract:
  Quantum--mechanical multiple--well oscillators exhibit curious complex
eigenvalues that resemble resonances in models with continuum spectra. We
discuss a method for the accurate calculation of their real and imaginary
parts.


title:
Optical/Infrared Observations of the Anomalous X-ray Pulsar 1E
  1048.1-5937 During Its 2007 X-Ray Flare

abstract:
  We report on optical and infrared observations of the anomalous X-ray pulsar
(AXP) 1E 1048.1-5937, made during its ongoing X-ray flare which started in 2007
March. We detected the source in the optical I and near-infrared Ks bands in
two ground-based observations and obtained deep flux upper limits from four
observations, including one with the Spitzer Space Telescope at 4.5 and 8.0
microns. The detections indicate that the source was approximately 1.3--1.6
magnitudes brighter than in 2003--2006, when it was at the tail of a previous
similar X-ray flare. Similar related flux variations have been seen in two
other AXPs during their X-ray outbursts, suggesting common behavior for large
X-ray flux variation events in AXPs. The Spitzer flux 1E 1048.1-5937 limits are
sufficiently deep that we can exclude mid-infrared emission similar to that
from the AXP 4U 0142+61, which has been interpreted as arising from a dust disk
around the AXP. The optical/near-infrared emission from probably has a
magnetospheric origin. The similarity in the flux spectra of 4U 0142+61 and 1E
1048.1-5937 challenges the dust disk model proposed for the latter.


title:
Local gradient estimates of p-harmonic functions, 1/H-flow, and an
  entropy formula

abstract:
  In the first part of this paper, we prove local interior and boundary
gradient estimates for p-harmonic functions on general Riemannian manifolds.
With these estimates, following the strategy in recent work of R. Moser, we
prove an existence theorem for weak solutions to the level set formulation of
the 1/H (inverse mean curvature) flow for hypersurfaces in ambient manifolds
satisfying a sharp volume growth assumption. In the second part of this paper,
we consider two parabolic analogues of the p-Laplace equation and prove sharp
Li-Yau type gradient estimates for positive solutions to these equations on
manifolds of nonnegative Ricci curvature. For one of these equations, we also
prove an entropy monotonicity formula generalizing an earlier such formula of
the second author for the linear heat equation. As an application of this
formula, we show that a complete Riemannian manifold with non-negative Ricci
curvature and sharp L^p-logarithmic Sobolev inequality must be isometric to
Euclidean space.


title: Viscous Dark Energy Models with Variable G and Lambda

abstract:
  We consider a cosmological model with bulk viscosity ($\eta$) and variable
cosmological $(\Lambda\propto \rho^{-\alpha}, \alpha=\rm const.$) and
gravitational ($G$) constants. The model exhibits many interesting cosmological
features. Inflation proceeds du to the presence of bulk viscosity and dark
energy without requiring the equation of state $p=-\rho$. During the
inflationary era the energy density ($\rho$) does not remain constant, as in
the de-Sitter type. Moreover, the cosmological and gravitational constants
increase exponentially with time, whereas the energy density and viscosity
decrease exponentially with time. The rate of mass creation during inflation is
found to be very huge suggesting that all matter in the universe was created
during inflation.


title:
A runaway collision in a young star cluster as the origin of the
  brightest supernova

abstract:
  Supernova 2006gy in the galaxy NGC 1260 is the most luminous one recorded
\cite{2006CBET..644....1Q, 2006CBET..647....1H, 2006CBET..648....1P,
2006CBET..695....1F}. Its progenitor might have been a very massive ($>100$
\msun) star \cite{2006astro.ph.12617S}, but that is incompatible with hydrogen
in the spectrum of the supernova, because stars $>40$ \msun are believed to
have shed their hydrogen envelopes several hundred thousand years before the
explosion \cite{2005A&A...429..581M}. Alternatively, the progenitor might have
arisen from the merger of two massive stars \cite{2007ApJ...659L..13O}. Here we
show that the collision frequency of massive stars in a dense and young cluster
(of the kind to be expected near the center of a galaxy) is sufficient to
provide a reasonable chance that SN 2006gy resulted from such a bombardment. If
this is the correct explanation, then we predict that when the supernova fades
(in a year or so) a dense cluster of massive stars becomes visible at the site
of the explosion.


title: Breakdown of universal transport in correlated d-wave superconductors

abstract:
  The prediction and observation of low-temperature universal thermal
conductivity in cuprates has served as a keystone of theoretical approaches to
the superconducting state, but recent measurements on underdoped samples show
strong violations of this apparently fundamental property of d-wave nodal
quasiparticles. Here, we show that the breakdown of universality may be
understood as the consequence of disorder-induced magnetic states in the
presence of increasing antiferromagnetic correlations in the underdoped state,
even as these same correlations protect the nodal low-energy density of states
in agreement with recent scanning tunneling experiments.


title:
Simulating Anisotropic Thermal Conduction in Supernova Remnants,
  Implications for the Interstellar Medium

abstract:
  We present a large number of two and a half dimensional simulations of
supernova remnants expanding into interstellar media having a range of
densities, temperatures and magnetic field strengths. The volume of hot gas
produced is strongly dependent on the inclusion of thermal conduction and
magnetic fields. The four-volumes and three-areas of hot gas have been
catalogued and their dependence on interstellar parameters documented.
Simulated line widths of radioactive species ejected by supernovae have also
been catalogued.


title: On rationality of W-algebras

abstract:
  We study the problem of classification of triples ($\mathfrak{g}, f, k$),
where $\mathfrak{g}$ is a simple Lie algebra, $f$ its nilpotent element and $k
\in \CC$, for which the simple $W$-algebra $W_k (\mathfrak{g}, f)$ is rational.


title: Traversable wormholes in a string cloud

abstract:
  We study spherically symmetric thin-shell wormholes in a string cloud
background in (3+1)-dimensional spacetime. The amount of exotic matter required
for the construction, the traversability and the stability under radial
perturbations, are analyzed as functions of the parameters of the model.
Besides, in the Appendices a non perturbative approach to the dynamics and a
possible extension of the analysis to a related model are briefly discussed.


title: Neutron scattering and extra short range interactions

abstract:
  The available data on neutron scattering were analyzed to constrain a
hypothetical new short-range interaction. We show that these constraints are
several orders of magnitude better than those usually cited in the range
between 1 pm and 5 nm. This distance range occupies an intermediate space
between collider searches for strongly coupled heavy bosons and searches for
new weak macroscopic forces. We emphasise the reliability of the neutron
constraints in so far as they provide several independent strategies. We have
identified the most promising way to improve them.


title:
Masses and Mixing of $c q \bar{q} \bar{q}$ Tetraquarks Using
  Glozman-Riska Hyperfine Interaction

abstract:
  In this paper we perform a detailed study of the masses and mixing of the
single charmed scalar tetraquarks: $c q \bar{q} \bar{q}$. We also give a
systematic analysis of these tetraquark states by weight diagrams, quantum
numbers and flavor wave functions. Tetraquark masses are calculated using four
different fits. The following SU(3)$_\mathrm{F}$ representations are discussed:
$\bar{15}_\mathrm{S}$, $\bar{3}_\mathrm{S}$, $6_\mathrm{A}$ and
$\bar{3}_\mathrm{A}$. We use the flavor-spin Glozman-Riska interaction
Hamiltonian with SU(3) flavor symmetry breaking. There are 27 different
tetraquarks composed of a charm quark $c$ and of the three light flavors $u, d,
s$: 11 cryptoexotic (3 D$_\mathrm{s}^{+}$, 4 D$^{+}$, 4 D$^{0}$) and 16
explicit exotic states. We discuss D$_\mathrm{s}$ and its isospin partners in
the same multiplet, as well as all the other four-quark states. Some explicit
exotic states appear in the spectrum with the same masses as
D$_\mathrm{s}^{+}$(2632) in $\bar{15}_\mathrm{S}$ and with the same masses as
D$_\mathrm{s}^{+}$(2317) in $6_\mathrm{A}$ representation, which confirm the
tetraquark nature of these states.


title:
Stationary strings and branes in the higher-dimensional Kerr-NUT-(A)dS
  spacetimes

abstract:
  We demonstrate complete integrability of the Nambu-Goto equations for a
stationary string in the general Kerr-NUT-(A)dS spacetime describing the
higher-dimensional rotating black hole. The stationary string in D dimensions
is generated by a 1-parameter family of Killing trajectories and the problem of
finding a string configuration reduces to a problem of finding a geodesic line
in an effective (D-1)-dimensional space. Resulting integrability of this
geodesic problem is connected with the existence of hidden symmetries which are
inherited from the black hole background. In a spacetime with p mutually
commuting Killing vectors it is possible to introduce a concept of a
$\xi$-brane, that is a p-brane with the worldvolume generated by these fields
and a 1-dimensional curve. We discuss integrability of such $\xi$-branes in the
Kerr-NUT-(A)dS spacetime.


title:
Entanglement Entropy, decoherence, and quantum phase transition of a
  dissipative two-level system

abstract:
  The concept of entanglement entropy appears in multiple contexts, from black
hole physics to quantum information theory, where it measures the entanglement
of quantum states. We investigate the entanglement entropy in a simple model,
the spin-boson model, which describes a qubit (two-level system) interacting
with a collection of harmonic oscillators that models the environment
responsible for decoherence and dissipation. The entanglement entropy allows to
make a precise unification between entanglement of the spin with its
environment, decoherence, and quantum phase transitions. We derive exact
analytical results which are confirmed by Numerical Renormalization Group
arguments both for an ohmic and a subohmic bosonic bath. Those demonstrate that
the entanglement entropy obeys universal scalings. We make comparisons with
entanglement properties in the quantum Ising model and in the Dicke model. We
also emphasize the possibility of measuring this entanglement entropy using
charge qubits subject to electromagnetic noise; such measurements would provide
an empirical proof of the existence of entanglement entropy.


title: Consequences of dark matter self-annihilation for galaxy formation

abstract:
  Galaxy formation requires a process that continually heats gas and quenches
star formation in order to reproduce the observed shape of the luminosity
function of bright galaxies. To accomplish this, current models invoke heating
from supernovae, and energy injection from active galactic nuclei. However,
observations of radio-loud active galactic nuclei suggest that their feedback
is likely to not be as efficient as required, signaling the need for additional
heating processes. We propose the self-annihilation of weakly interacting
massive particles that constitute dark matter as a steady source of heating. In
this paper, we explore the circumstances under which this process may provide
the required energy input. To do so, dark matter annihilations are incorporated
into a galaxy formation model within the Millennium cosmological simulation.
Energy input from self-annihilation can compensate for all the required gas
cooling and reproduce the observed galaxy luminosity function only for what
appear to be extreme values of the relevant key parameters. The key parameters
are: the slope of the inner density profile of dark matter haloes and the outer
spike radius. The inner density profile needs to be steepened to slopes of -1.5
or more and the outer spike radius needs to extend to a few tens of parsecs on
galaxy scales and a kpc or so on cluster scales. If neutralinos or any thermal
relic WIMP with s-wave annihilation constitute dark matter, their
self-annihilation is inevitable and could provide enough power to modulate
galaxy formation. Energy from self-annihilating WIMPs could be yet another
piece of the feedback puzzle along with supernovae and active galactic nuclei.


title: Low-Mass X-ray Binaries and Globular Clusters in Centaurus A

abstract:
  We present results of Hubble Space Telescope and Chandra X-ray Observatory
observations of globular clusters (GCs) and low-mass X-ray binaries (LMXBs) in
the central regions of Centaurus A. Out of 440 GC candidates we find that 41
host X-ray point sources that are most likely LMXBs. We fit King models to our
GC candidates in order to measure their structural parameters. We find that GCs
that host LMXBs are denser and more compact, and have higher encounter rates
and concentrations than the GC population as a whole. We show that the higher
concentrations and masses are a consequence of the dependence of LMXB incidence
on central density and size plus the general trend for denser GCs to have
higher masses and concentrations. We conclude that neither concentration nor
mass are fundamental variables in determining the presence of LMXBs in GCs, and
that the more fundamental parameters relate to central density and size.


title:
A Technique for Detecting Starlight Scattered from Transiting Extrasolar
  Planets with Application to HD 209458b

abstract:
  We present a new technique for detecting scattered starlight from transiting,
close-orbiting extrasolar giant planets (CEGPs) that has the virtues of
simplicity, robustness, linearity, and model-independence. Given a series of
stellar spectra obtained over various phases of the planetary orbit, the goal
is to measure the strength of the component scattered by the planet relative to
the component coming directly from the star. We use two complementary
strategies, both of which rely on the predictable Doppler shifts of both
components and on combining the results from many spectral lines and many
exposures. In the first strategy, we identify segments of the stellar spectrum
that are free of direct absorption lines and add them after Doppler-shifting
into the planetary frame. In the second strategy, we compare the distribution
of equivalent-width ratios of the scattered and direct components. Both
strategies are calibrated with a ``null test'' in which scrambled Doppler
shifts are applied to the spectral segments. As an illustrative test case, we
apply our technique to spectra of HD 209458 taken when the planet was near
opposition (with orbital phases ranging from 11 to 34$\arcdeg$, where
0$\arcdeg$ is at opposition), finding that the planet-to-star flux ratio is
$(1.4 \pm 2.9)\times10^{-4}$ in the wavelength range 554$-$681 nm. This
corresponds to a geometric albedo of $0.8 \pm 1.6$, assuming the phase function
of a Lambert sphere. Although the result is not statistically significant, the
achieved sensitivity and relatively small volume of data upon which it is based
are very encouraging for future ground-based spectroscopic studies of scattered
light from transiting CEGP systems.


title: IMAGES I. Strong evolution of galaxy kinematics since z=1

abstract:
  (abbreviated) We present the first results of the ESO large program,
``IMAGES'' which aims at obtaining robust measurements of the kinematics of
distant galaxies using the multi-IFU mode of GIRAFFE on the VLT. 3D
spectroscopy is essential to robustly measure the often distorted kinematics of
distant galaxies (e.g., Flores et al. 2006). We derive the velocity fields and
$\sigma$-maps of 36 galaxies at 0.4<z<0.75 from the kinematics of the [OII]
emission line doublet, and generate a robust technique to identify the nature
of the velocity fields based on the pixels of the highest signal-to-noise
ratios (S/N). We have gathered a unique sample of 63 velocity fields of
emission line galaxies (W0([OII]) > 15 A) at z=0.4-0.75, which are a
representative subsample of the population of M_stellar>1.5x10^{10} M_sun
emission line galaxies in this redshift range, and are largely unaffected by
cosmic variance. Taking into account all galaxies -with or without emission
lines- in that redshift range, we find that at least 41+/-7% of them have
anomalous kinematics, i.e., they are not dynamically relaxed. This includes
26+/-7% of distant galaxies with complex kinematics, i.e., they are not simply
pressure or rotationally supported. Our result implies that galaxy kinematics
are among the most rapidly evolving properties, because locally, only a few
percent of the galaxies in this mass range have complex kinematics.


title: TeV gravity in four dimensions?

abstract:
  We describe a model in which the fundamental scale M_\star of the theory
which unifies gravity and quantum mechanics is in the TeV range, but without
requiring additional spacetime dimensions. The weakness of gravity at low
energies is due to a large vacuum expectation of a dilaton like field. The
model requires a small dimensionless parameter (the self-coupling of the
dilaton) but no fine-tuning. We discuss in detail the dynamical assumptions
about nonperturbative quantum gravity required within the model. We observe
that M_\star could be quite small, less than a TeV, and that the model could
lead to copious strong coupling effects at the LHC. However, semiclassical
black holes will not be produced.


title:
Horocycle flows for laminations by hyperbolic Riemann surfaces and
  Hedlund's theorem

abstract:
  We study the dynamics of the geodesic and horocycle flows of the unit tangent
bundle $(\hat M, T^1\mathcal{F})$ of a compact minimal lamination $(M,\mathcal
F)$ by negatively curved surfaces. We give conditions under which the action of
the affine group generated by the joint action of these flows is minimal, and
examples where this action is not minimal. In the first case, we prove that if
$\mathcal F$ has a leaf which is not simply connected, the horocyle flow is
topologically transitive.


title: Metal Absorption Systems in Spectra of Pairs of QSOs

abstract:
  We present the first large sample of absorption systems in paired QSOs
consisting of 691 absorption systems in the spectra of 310 QSOs including 170
pairings. All these absorption systems have metal lines, usually C IV or Mg II.
We see 17 cases of absorption in one line-of-sight within 200 km/s (1 Mpc) of
absorption in the paired line-of-sight with the probability at least approx 50%
at 100kpc, declining rapidly to 23% at 100 - 200 kpc. We detect clustering on
0.5Mpc scales and see a hint of the "fingers of God" redshift-space distortion.
The distribution matches absorbers arising in galaxies at z=2 with a normal
correlation function and systematic infall velocities but unusually low random
pair-wise velocity differences. Absorption in gas flowing out from galaxies at
a mean velocity of 250 km/s would produce vastly more elongation than we see.
The UV absorption from fast winds that Adelberger et al. 2005 see in spectra of
LBGs is not representative of the absorption that we see. Either the winds are
confined to LBGs, or they can not extend to 40 kpc with large velocities, while
continuing to make UV absorption we see, implying most metals were in place in
the IGM long before z=2. Separately, when we examine the absorption seen when a
sight line passes a second QSO, we see 19 absorbers within 400 km/s of the
partner QSO. The probability of seeing absorption is approximately constant for
impact parameters 0.1 - 1.5 Mpc. Perhaps we do not see a rapid rise in the
probability at small impact parameters because the UV from QSOs destroys some
absorbers near to the QSOs. The 3D distribution of 64 absorbers around 313 QSOs
is to first order isotropic, with just a hint of the anisotropy expected if the
QSO UV emission is beamed, or alternatively QSOs might emit UV isotropically
but for a surprisingly short time of only 0.3Myr.


title: Dissipative Quantum Ising model in a cold atomic spin-boson mixture

abstract:
  Using cold bosonic atoms with two (hyperfine) ground states, we introduce a
spin-boson mixture which allows to implement the quantum Ising model in a
tunable dissipative environment. The first specie lies in a deep optical
lattice with tightly confining wells and forms a spin array; spin-up/down
corresponds to occupation by one/no atom at each site. The second specie forms
a superfluid reservoir. Different species are coupled coherently via laser
transitions and collisions. Whereas the laser coupling mimics a transverse
field for the spins, the coupling to the reservoir sound modes induces a
ferromagnetic (Ising) coupling as well as dissipation. This gives rise to an
order-disorder quantum phase transition where the effect of dissipation can be
studied in a controllable manner.


title: Thou Shalt Not Clone One Bit!

abstract:
  We prove a no-triplets theorem for spin 1 particles, which implies a
strengthened form of the no-cloning theorem.


title:
Cosmological consequences of scalar mesons from gauge/gravity
  correspondence

abstract:
  We consider the spectrum of mesons for the gauge theory dual to a
supergravity configuration of intersecting D3/D7 branes, and use the expression
for the Lagrangian of the scalar mesons to compute explicitly the Lagrangian
for the lightest states in the infrared limit. Assuming that the matter content
of this gauge theory is part of a hidden sector, which interacts with the
standard model only via gravity, we explore the cosmological consequences of
these lightest scalar mesons for a FRW universe. We show that phantom fields
may appear naturally in this kind of scenarios.


title:
The Polarization of Scattered Lyman Alpha Radiation Around High-Redshift
  Galaxies

abstract:
  The high-redshift Universe contains luminous Lyman Alpha (hereafter Lya)
emitting sources such as galaxies and quasars. The emitted Lya radiation is
often scattered by surrounding neutral hydrogen atoms. We show that the
scattered Lya radiation obtains a high level of polarization for a wide range
of likely environments of high-redshift galaxies. For example, the
back-scattered Lya flux observed from galaxies surrounded by a superwind-driven
outflow may reach a fractional polarization as high as ~40%. Equal levels of
polarization may be observed from neutral collapsing protogalaxies. Resonant
scattering in the diffuse intergalactic medium typically results in a lower
polarization amplitude (<7%), which depends on the flux of the ionizing
background. Spectral polarimetry can differentiate between Lya scattering off
infalling gas and outflowing gas; for an outflow the polarization should
increase towards longer wavelengths while for infall the opposite is true. Our
numerical results suggest that Lya polarimetry is feasible with existing
instruments, and may provide a new diagnostic of the distribution and
kinematics of neutral hydrogen around high-redshift galaxies. Moreover,
polarimetry may help suppress infrared lines originating in the Earth's
atmosphere, and thus improve the sensitivity of ground-based observations to
high-redshift Lya emitting galaxies outside the currently available redshift
windows.


title:
The gas emission spectrum in a star-forming region in the BCD galaxy VII
  Zw 403 (UGC 6456)

abstract:
  Observations with the 6-m telescope of the Special Astrophysical Observatory
obtained with the MPFS integral-field spectrograph and a longslit spectrograph
with the SCORPIO focal reducer are used to analyze the emission spectrum of the
ionized gas in a star-forming region in the BCD galaxy VII Zw 403. We present
images of the galactic central region in the H-alpha, H-beta, [SII], and [OIII]
emission lines, together with maps of the relative [OIII]/H-beta and
[SII]/H-alpha intensities. We have determined the parameters of the gas in
bright ionized supershells, and estimated the relative abundances of oxygen,
nitrogen, and sulfur; a low relative N/O abundance was detected.


title:
Finite size effects and symmetry breaking in the evolution of networks
  of competing Boolean nodes

abstract:
  The effects of the finite size of the network on the evolutionary dynamics of
a Boolean network are analyzed. In the model considered, Boolean networks
evolve via a competition between nodes that punishes those in the majority. It
is found that finite size networks evolve in a fundamentally different way than
infinitely large networks do. The symmetry of the evolutionary dynamics of
infinitely large networks that selects for canalizing Boolean functions is
broken in the evolutionary dynamics of finite size networks. In finite size
networks there is an additional selection for input inverting Boolean functions
that output a value opposite to the majority of input values. These results are
revealed through an empirical study of the model that calculates the frequency
of occurrence of the different possible Boolean functions. Classes of functions
are found to occur with the same frequency. Those classes depend on the
symmetry of the evolutionary dynamics and correspond to orbits of the relevant
symmetry group. The empirical results match analytic results, determined by
utilizing Polya's theorem, for the number of orbits expected in both finite
size and infinitely large networks. The reason for the symmetry breaking in the
evolutionary dynamics is found to be due to the need for nodes in finite size
networks to behave differently in order to cooperate so that the system
collectively performs as well as possible. The results suggest that both finite
size effects and symmetry are important for understanding the evolution of
real-world complex networks, including genetic regulatory networks.

categories: cond-mat.stat-mech cond-mat.dis-nn nlin.AO physics.bio-ph physics.soc-ph q-bio.PE


title:
Uncertainty relations for the realisation of macroscopic quantum
  superpositions and EPR paradoxes

abstract:
  We present a unified approach, based on the use of quantum uncertainty
relations, for arriving at criteria for the demonstration of the EPR paradox
and macroscopic superpositions. We suggest to view each criterion as a means to
demonstrate an EPR-type paradox, where there is an inconsistency between the
assumptions of a form of realism, either macroscopic realism (MR) or local
realism (LR), and the completeness of quantum mechanics.


title: Spallation nuclei in substellar objects: a new dark-matter signature?

abstract:
  Although dark matter makes up 80% of the gravitational mass of our Galaxy,
its composition is not known. One hypothesis is that dark matter consists of
massive particles called WIMPs. WIMPs are expected to accumulate and
coannihilate in the cores of stars, but the only signature of this accumulation
has been thought to be hard- to-observe high-energy neutrinos. Here we propose
an entirely new observable signature. WIMP coannihilations in the core of a
very low-mass star, brown dwarf, or planetary-mass object should alter the
star's chemical composition via spallation reactions. Very close to the
Galactic center, these stars may acquire extremely high lithium, beryllium, and
boron abundances, even for models with otherwise- undetectable WIMP-nucleon
cross sections. These abundances should be measurable in certain stellar
systems and phenomena.


title: Intergalactic absorption and blazar gamma-ray spectra

abstract:
  The distribution of TeV spectral slopes versus redshift for currently known
TeV blazars (16 sources with z<0.21, and one with z>0.25) is essentially a
scatter plot with hardly any hint of a global trend. We suggest that this is
the outcome of two combined effects of intergalactic gamma-gamma absorption,
plus an inherent feature of the SSC (synchro-self-Compton) process of blazar
emission. First, flux dimming introduces a bias that favors detection of
progressively more flaring sources at higher redshifts. According to mainstream
SSC models, more flaring source states imply sources with flatter TeV slopes.
This results in a structured relation between intrinsic TeV slope and redshift.
The second effect, spectral steepening by intergalactic absorption, affects
sources progressively with distance and effectively wipes out the intrinsic
slope-redshift correlation.


title: The 't Hooft-Polyakov Monopole in the Presence of a 't Hooft Operator

abstract:
  We present explicit BPS field configurations representing one nonabelian
monopole with one minimal weight 't Hooft operator insertion. We explore the
SO(3) and SU(2) gauge groups. In the case of SU(2) gauge group the minimal 't
Hooft operator can be completely screened by the monopole. If the gauge group
is SO(3), however, such screening is impossible. In the latter case we observe
a different effect of the gauge symmetry enhancement in the vicinity of the 't
Hooft operator.


title: Statefinder diagnostic for Yang-Mills dark energy model

abstract:
  We study the statefinder parameters in the Yang-Mills condensate dark energy
models, and find that the evolving trajectories of these models are different
from those of other dark energy models. We also define two eigenfunctions of
the Yang-Mills condensate dark energy models. The values of these
eigenfunctions are quite close to zero if the equation-of-state of the
Yang-Mills condensate is not far from -1, which can be used to simply
differentiate between the Yang-Mills condensate models and other dark energy
models.


title:
Zhedanov's Algebra AW(3) and the Double Affine Hecke Algebra in the Rank
  One Case. II. The Spherical Subalgebra

abstract:
  This paper builds on the previous paper arXiv:math/0612730 by the author,
where a relationship between Zhedanov's algebra AW(3) and the double affine
Hecke algebra (DAHA) corresponding to the Askey-Wilson polynomials was
established. It is shown here that the spherical subalgebra of this DAHA is
isomorphic to AW(3) with an additional relation that the Casimir operator
equals an explicit constant. A similar result with q-shifted parameters holds
for the antispherical subalgebra. Some theorems on centralizers and centers for
the algebras under consideration will finally be proved as corollaries of the
characterization of the spherical and antispherical subalgebra.


title: Testable polarization predictions for models of CMB isotropy anomalies

abstract:
  Anomalies in the large-scale CMB temperature sky measured by WMAP have been
suggested as possible evidence for a violation of statistical isotropy on large
scales. In any physical model for broken isotropy, there are testable
consequences for the CMB polarization field. We develop simulation tools for
predicting the polarization field in models that break statistical isotropy
locally through a modulation field. We study two different models: dipolar
modulation, invoked to explain the asymmetry in power between northern and
southern ecliptic hemispheres, and quadrupolar modulation, posited to explain
the alignments between the quadrupole and octopole. For the dipolar case, we
show that predictions for the correlation between the first 10 multipoles of
the temperature and polarization fields can typically be tested at better than
the 98% CL. For the quadrupolar case, we show that the polarization quadrupole
and octopole should be moderately aligned. Such an alignment is a generic
prediction of explanations which involve the temperature field at recombination
and thus discriminate against explanations involving foregrounds or local
secondary anisotropy. Predicted correlations between temperature and
polarization multipoles out to l = 5 provide tests at the ~ 99% CL or stronger
for quadrupolar models that make the temperature alignment more than a few
percent likely. As predictions of anomaly models, polarization statistics move
beyond the a posteriori inferences that currently dominate the field.


title: Relativistic corrections to the static potential at O(1/m) and O(1/m^2)

abstract:
  We investigate the relativistic corrections to the static potential, i.e. the
O(1/m) potential and the O(1/m^2) velocity-dependent potentials, in SU(3)
lattice gauge theory. They are important ingredients of potential
nonrelativistic QCD for heavy quarkonium. Utilizing the multi-level algorithm,
we obtain remarkably clean signals of these potentials up to r=0.9 fm. We
observe long range nonperturbative contributions to these corrections.


title: Irreversible Circulation of Fluctuation and Entropy Production

abstract:
  Physical and chemical stochastic processes described by the master equation
are investigated. In this paper, we examine the entropy production both for the
master equation and for the corresponding Fokker-Planck equation. For the
master equation, the exact expression of the entropy production was recently
derived by Gaspard using the Kolmogorov-Sinai entropy ({\em J.Stat.Phys.},
\textbf{117} (2004), 599; [Errata; \textbf{126} (2006), 1109 ]). Although
Gaspard's expression is derived from a stochastic consideration, it should be
noted that Gaspard's expression conincides with the thermodynamical expression.
For the corresponding Fokker-Planck equation, by using the detailed imbalance
relation which appears in the derivation process of the fluctuation theorem
through the Onsger-Machlup theory, the entropy production is expressed in terms
of the {\em irreversible circulation of fluctuation}, which was proposed by
Tomita and Tomita ({\em Prog.Theor.Phys.}, \textbf{51} (1974), 1731). However,
this expression for the corresponding Fokker-Planck equation differs from that
of the entropy production for the master equation. This discrepancy is due to
the difference between the master equation and the corresponding Fokker-Planck
equation, namely the former treats discrete events, but the latter equation is
an approximation of the former one. In fact, in the latter equation, the
original discrete events are smoothed out. To overcome this difficulty, we
propose the {\em path weight principle}. By using this principle, the modified
expression of the entropy production for the corresponding Fokker-Planck
equation coincides with that of the master equation (i.e., the thermodynamical
expression) for a simple chemical reaction system and a diffusion system.


title:
Rigidity and relative hyperbolicity of real hyperbolic hyperplane
  complements

abstract:
  For n>3 we study spaces obtained from finite volume complete real hyperbolic
n-manifolds by removing a compact totally geodesic submanifold of codimension
two. We prove that their fundamental groups are relative hyperbolic, co-Hopf,
biautomatic, residually hyperbolic, not K\"ahler, not isomorphic to lattices in
virtually connected real Lie groups, have no nontrivial subgroups with property
(T), have finite outer automorphism groups, satisfy Mostow-type Rigidity, have
finite asymptotic dimension and rapid decay property, and satisfy Baum-Connes
conjecture. We also characterize those lattices in real Lie groups that are
isomorphic to relatively hyperbolic groups.


title:
Collective spin systems in dispersive optical cavity QED: Quantum phase
  transitions and entanglement

abstract:
  We propose a cavity QED setup which implements a dissipative
Lipkin-Meshkov-Glick model -- an interacting collective spin system. By varying
the external model parameters the system can be made to undergo both first-and
second-order quantum phase transitions, which are signified by dramatic changes
in cavity output field properties, such as the probe laser transmission
spectrum. The steady-state entanglement between pairs of atoms is shown to peak
at the critical points and can be experimentally determined by suitable
measurements on the cavity output field. The entanglement dynamics also
exhibits pronounced variations in the vicinities of the phase transitions.


title: Reflecting on Cherenkov reflections

abstract:
  Magic Telescope may observe and reveal at horizons lights from air-shower
Cherenkov reflections. The ground, the sea, the cloudy sky (below the mountain)
may reflect PeVs-EeV UHECR Cherenkov lights observable by MAGIC telescopes.
Even rarest UHE neutrino skimming the atmosphere or skimming the Earth may
induce upward-horizontal airshowers: a new Neutrino Astronomy. These
fluorescence signals or the Cherenkov reflections in upper cloudy sky may flash
in correlated BL-Lac or GRB shining at opposite edges. Geomagnetic splitting of
Horizontal Air-showers may offer a new spectroscopy of UHECR from the knee up
to GZK energy edges.


title:
Spectropolarimetric observations of Herbig Ae/Be Stars I: HiVIS
  spectropolarimetric calibration and reduction techniques

abstract:
  Using the HiVIS spectropolarimeter built for the Haleakala 3.7m AEOS
telescope in Hawaii, we are collecting a large number of high precision
spectropolarimetrc observations of stars. In order to precisely measure very
small polarization changes, we have performed a number of polarization
calibration techniques on the AEOS telescope and HiVIS spectrograph. We have
extended our dedicated IDL reduction package and have performed some hardware
upgrades to the instrument. We have also used the ESPaDOnS spectropolarimeter
on CFHT to verify the HiVIS results with back-to-back observations of MWC 361
and HD163296. Comparision of this and other HiVIS data with stellar
observations from the ISIS and WW spectropolarimeters in the literature further
shows the usefulness of this instrument.


title: Entanglement generation using silicon wire waveguide

abstract:
  We report the first entanglement generation experiment that utilizes a
silicon waveguide. Using spontaneous four-wave mixing in a 1.09-cm-long silicon
wire waveguide, we generated 1.5-um, high-purity time-bin entangled photons
without temperature control, and observed a two-photon interference fringe with
>73% visibility.


title:
Time-reversal symmetry breaking by a $(d+id)$ density-wave state in
  underdoped cuprate superconductors

abstract:
  It was proposed that the $id_{x^2-y^2}$ density-wave state (DDW) may be
responsible for the pseudogap behavior in the underdoped cuprates. Here we show
that the admixture of a small $d_{xy}$ component to the DDW state breaks the
symmetry between the counter-propagating orbital currents of the DDW state and,
thus, violates the macroscopic time-reversal symmetry. This symmetry breaking
results in a non-zero polar Kerr effect, which has recently been observed in
the pseudogap phase.


title:
Black Hole Evaporation and Generalized 2nd Law with Nonequilibrium
  Thermodynamics

abstract:
  In general, when a black hole evaporates, there arises a net energy flow from
black hole into its outside environment due to Hawking radiation and energy
accretion onto black hole. The existence of energy flow means that the
thermodynamic state of the whole system, which consists of a black hole and its
environment, is in a nonequilibrium state. To know the detail of evaporation
process, the nonequilibrium effects of energy flow should be taken into
account. The nonequilibrium nature of black hole evaporation is a challenging
topic including issues of not only black hole physics but also nonequilibrium
physics. Using the nonequilibrium thermodynamics which has been formulated
recently, this report shows: (1) the self-gravitational effect of black hole
which appears as its negative heat capacity guarantees the validity of
generalized 2nd law without entropy production inside the outside environment,
(2) the nonequilibrium effect of energy flow tends to shorten the evaporation
time (life time) of black hole, and consequently specific nonequilibrium
phenomena are suggested. Finally a future direction of this study is commented.


title:
A shape of charged particle lateral distribution in individual EAS
  events with energy above 10^19 eV arriving from different celestial regions

abstract:
  A shape of lateral distribution for charged particles in events with energy
above 10^19eV is considered. Two methods were used for individual LDF
parametrization. In the first approach, the index of power was determined for
generalized Greisen-Linsley approximation. In second, mean square radius of the
shower was determined for approximation proposed by Lagutin et al. Comparison
of resulted parameters is presented for individual events arrived from
different celestial regions -- Galactic planes and the region with increased
flux of particles with E(0)>=10^19eV (according to Yakutsk array): 1.7h-3.7h
right ascension; 45-60 degrees declination.


title:
Generation of slow intense optical solitons in a resonance photonic
  crystal

abstract:
  We demonstrate interesting and previously unforeseen properties of a pair of
gap solitons in a resonant photonic crystal which are predicted and explained
in a physically transparent form using both analytical and numerical methods.
The most important result is the fact that an oscillating gap soliton created
by the presence of a localized population inversion inside the crystal can be
manipulated by means of a proper choice of bit rate, phase and amplitude
modulation. Developing this idea, we are able to obtain qualitatively different
regimes of a resonant photonic crystal operation. In particular, a noteworthy
observation is that both the delay time and amplitude difference must exceed a
certain level to ensure effective control over the soliton dynamics.


title:
The Structures of Distant Galaxies I: Galaxy Structures and the Merger
  Rate to z~3 in the Hubble Ultra-Deep Field

abstract:
  This paper begins a series in which we examine the structures of distant
galaxies to directly determine the history of their formation modes. We start
this series by examining the structures of z_F850LP < 27 galaxies in the Hubble
Ultra-Deep field, the deepest high-resolution optical image taken to date. We
investigate a few basic features of galaxy structure using this image. These
include: (1) The agreement of visual eye-ball classifications and
non-parametric quantitative (CAS, Gini/M_20) methods; (2) How distant galaxy
quantitative structures can vary as a function of rest-frame wavelength; and
(3) The evolution of distant galaxy structures up to z~3. One of our major
conclusions is that the majority of galaxies with z_850 < 27 are peculiar in
appearance, and that galaxy assembly is rapidly occurring at these magnitudes,
even up to the present time. We find a general agreement between galaxy
classification by eye and through quantitative methods, as well as a general
agreement between the CAS and the Gini/M_20 parameters. We find that the
Gini/M_20 method appears to find a larger number of galaxy mergers than the CAS
system, but contains a larger contamination from non-mergers. We furthermore
calculate the merger rate of galaxies in the UDF up to z~3, finding an increase
with redshift as well as stellar mass, confirming previous work in the Hubble
Deep Field. We find that massive galaxies with M_{*} > 10^10 M_0 undergo
4.3_+0.8^-0.8 major galaxy mergers at z < 3, with all of this merging occurring
at z > 1.


title: Encouraging the grand coalition in convex cooperative games

abstract:
  A solution function for convex transferable utility games encourages the
grand coalition if no player prefers (in a precise sense defined in the text)
any coalition to the grand coalition. We show that the Shapley value encourages
the grand coalition in all convex games and the tau-value encourages the grand
coalitions in convex games up to three (but not more than three) players.
Solution functions that encourage the grand coalition in convex games always
produce allocations in the core, but the converse is not necessarily true.


title: Melosh rotation: source of the proton's missing spin

abstract:
  It is shown that the observed small value of the integrated spin structure
function for protons could be naturally understood within the naive quark model
by considering the effect from Melosh rotation. The key to this problem lies in
the fact that the deep inelastic process probes the light-cone quarks rather
than the instant-form quarks, and that the spin of the proton is the sum of the
Melosh rotated light-cone spin of the individual quarks rather than simply the
sum of the light-cone spin of the quarks directly.


title:
Magnetic Field versus Temperature Phase Diagram of the Spin-1/2
  Alternating Chain Compound F5PNN

abstract:
  We have measured the specific heat of the S = 1/2 alternating Heisenberg
antiferromagnetic chain compound pentafluorophenyl nitronyl nitroxide in
magnetic fields using a single crystal and powder. A sharp peak due to
field-induced magnetic ordering (FIMO) is observed in both samples. The H-T
phase boundary of the FIMO of the single crystal is symmetric with respect to
the central field of the gapless field region HC1 < H < HC2, whereas it is
distorted for the powder whose ordering temperatures are lower. An analysis
employing calculations based on the finite temperature density matrix
renormalization group indicates the possibility of novel incommensurate
ordering due to frustration in the powder around the central field.


title: Revealing Substructure in the Galactic Halo - The SEKBO RR Lyrae Survey

abstract:
  We present a search for RR Lyrae variable stars from archival observations of
the Southern Edgeworth-Kuiper Belt Object survey. The survey covers 1675 square
degrees along the ecliptic to a mean depth of V=19.5, i.e. a heliocentric
distance of ~50kpc for RR Lyrae stars. The survey reveals 2016 RR Lyrae
candidates. Follow-up photometric monitoring of a subset of these candidates
shows (24+/-12)% contamination by non-RR Lyrae variables. We derive a map of
over-density of RR Lyraes in the halo that reveals a series of structures
coincident with the leading and trailing arms of debris from the Sagittarius
dwarf galaxy. One of the regions of over-density is found on the trailing arm,
200 deg. from the main body of the Sagittarius dwarf at a distance of ~45kpc.
This distant detection of the stellar population of the outer trailing arm of
Sagittarius offers a tight constraint on the motion of the dwarf galaxy. A
distinctly separate region of over-density is seen towards the Virgo Over
Density.


title:
On the hierarchy of partially invariant submodels of differential
  equations

abstract:
  It is noticed, that partially invariant solution (PIS) of differential
equations in many cases can be represented as an invariant reduction of some
PIS of the higher rank. This introduce a hierarchic structure in the set of all
PISs of a given system of differential equations. By using this structure one
can significantly decrease an amount of calculations required in enumeration of
all PISs for a given system of partially differential equations. An equivalence
of the two-step and the direct ways of construction of PISs is proved. In this
framework the complete classification of regular partially invariant solutions
of ideal MHD equations is given.


title:
Bulk electronic structure of the antiferromagnetic superconducting phase
  in ErNi2B2C

abstract:
  We have performed temperature (T) - dependent laser-photoemission
spectroscopy of antiferromagnetic (AF) superconductor ErNi2B2C to study the
electronic-structure evolution reflecting the interplay between
antiferromagnetism and superconductivity. The spectra at the superconducting
(SC) phase show a very broad spectral shape. T-dependent SC gap shows a sudden
deviation from the BCS prediction just below TN. This observation can be well
explained by the theoretical model and thus represents characteristic bulk
electronic structure of the AF SC phase for the first time.


title:
Edge-functionalized and substitutional doped graphene nanoribbons:
  electronic and spin properties

abstract:
  Graphene nanoribbons are the counterpart of carbon nanotubes in
graphene-based nanoelectronics. We investigate the electronic properties of
chemically modified ribbons by means of density functional theory. We observe
that chemical modifications of zigzag ribbons can break the spin degeneracy.
This promotes the onset of a semiconducting-metal transition, or of an
half-semiconducting state, with the two spin channels having a different
bandgap, or of a spin-polarized half-semiconducting state -where the spins in
the valence and conduction bands are oppositely polarized. Edge
functionalization of armchair ribbons gives electronic states a few eV away
from the Fermi level, and does not significantly affect their bandgap. N and B
produce different effects, depending on the position of the substitutional
site. In particular, edge substitutions at low density do not significantly
alter the bandgap, while bulk substitution promotes the onset of
semiconducting-metal transitions. Pyridine-like defects induce a
semiconducting-metal transition.


title: Conservation laws for a general Lorentz connection

abstract:
  We derive conservation laws for energy-momentum (canonical and dynamical) and
angular momentum for a general Lorentz connection.


title: Adjoint ideals along closed subvarieties of higher codimension

abstract:
  In this paper, we introduce a notion of adjoint ideal sheaves along closed
subvarieties of higher codimension and study its local properties using
characteristic $p$ methods. When $X$ is a normal Gorenstein closed subvariety
of a smooth complex variety $A$, we formulate a restriction property of the
adjoint ideal sheaf $\adj_X(A)$ of $A$ along $X$ involving the l.c.i. ideal
sheaf $\mathcal{D}_X$ of $X$. The proof relies on a modification of generalized
test ideals of Hara and Yoshida.


title:
Quantum non-demolition measurements of single donor spins in
  semiconductors

abstract:
  We propose a technique for measuring the state of a single donor electron
spin using a field-effect transistor induced two-dimensional electron gas and
electrically detected magnetic resonance techniques. The scheme is facilitated
by hyperfine coupling to the donor nucleus. We analyze the potential
sensitivity and outline experimental requirements. Our measurement provides a
single-shot, projective, and quantum non-demolition measurement of an
electron-encoded qubit state.


title: Building Giant-Planet Cores at a Planet Trap

abstract:
  A well-known bottleneck for the core-accretion model of giant-planet
formation is the loss of the cores into the star by Type-I migration, due to
the tidal interactions with the gas disk. It has been shown that a steep
surface-density gradient in the disk, such as the one expected at the boundary
between an active and a dead zone, acts as a planet trap and prevents isolated
cores from migrating down to the central star. We study the relevance of the
planet trap concept for the accretion and evolution of systems of multiple
planetary embryos/cores. We performed hydrodynamical simulations of the
evolution of systems of multiple massive objects in the vicinity of a planet
trap. The planetary embryos evolve in 3 dimensions, whereas the disk is modeled
with a 2D grid. Synthetic forces are applied onto the embryos to mimic the
damping effect that the disk has on their inclinations. Systems with two
embryos tend to acquire stable, separated and non-migrating orbits, with the
more massive embryo placed at the planet trap and the lighter one farther out
in the disk. Systems of multiple embryos are intrinsically unstable.
Consequently, a long phase of mutual scattering can lead to accreting
collisions among embryos; some embryos are injected into the inner part of the
disk, where they can be evacuated into the star by Type I migration. The system
can resume a stable, non-migrating configuration only when the number of
surviving embryos decreases to a small value (~2-4). This can explain the
limited number of giant planets in our solar system. These results should apply
in general to any case in which the Type-I migration of the inner embryo is
prevented by some mechanism, and not solely to the planet trap scenario.


title: Models for dependent extremes using stable mixtures

abstract:
  This paper unifies and extends results on a class of multivariate Extreme
Value (EV) models studied by Hougaard, Crowder, and Tawn. In these models both
unconditional and conditional distributions are EV, and all lower-dimensional
marginals and maxima belong to the class. This leads to substantial economies
of understanding, analysis and prediction. One interpretation of the models is
as size mixtures of EV distributions, where the mixing is by positive stable
distributions. A second interpretation is as exponential-stable location
mixtures (for Gumbel) or as power-stable scale mixtures (for non-Gumbel EV
distributions). A third interpretation is through a Peaks over Thresholds model
with a positive stable intensity. The mixing variables are used as a modeling
tool and for better understanding and model checking. We study extreme value
analogues of components of variance models, and new time series, spatial, and
continuous parameter models for extreme values. The results are applied to data
from a pitting corrosion investigation.


title: $k$-noncrossing RNA structures with arc-length $\ge 3$

abstract:
  In this paper we enumerate $k$-noncrossing RNA pseudoknot structures with
given minimum arc- and stack-length. That is, we study the numbers of RNA
pseudoknot structures with arc-length $\ge 3$, stack-length $\ge \sigma$ and in
which there are at most $k-1$ mutually crossing bonds, denoted by ${\sf
T}_{k,\sigma}^{[3]}(n)$. In particular we prove that the numbers of 3, 4 and
5-noncrossing RNA structures with arc-length $\ge 3$ and stack-length $\ge 2$
satisfy ${\sf T}_{3,2}^{[3]}(n)^{}\sim K_3 n^{-5} 2.5723^n$, ${\sf
T}^{[3]}_{4,2}(n)\sim K_4 n^{-{21/2}} 3.0306^n$, and ${\sf
T}^{[3]}_{5,2}(n)\sim K_5 n^{-18} 3.4092^n$, respectively, where $K_3,K_4,K_5$
are constants. Our results are of importance for prediction algorithms for RNA
pseudoknot structures.


title:
Recrystallization of glass: homogeneous vs. heterogeneous nucleation in
  La(0.5)Ca(0.5)MnO3

abstract:
  We probe through magnetization and resistivity measurements a kinetically
arrested glass-like but long-range ordered magnetic state. The transformation
kinetics of the magnetic field-temperature induced broad first-order transition
from ferromagnetic-metallic (FMM) to antiferromagnetic-insulating (AFI) state
gets hindered at low temperature in a La(0.5)Ca(0.5)MnO3 sample. A fraction of
high-temperature FMM phase persists to the lowest temperature, albeit as a
non-ergodic state. We present a phenomenology for this glass-like but
long-range order FMM phase which devitrifies on heating and converts to
equilibrium AFI phase. The residual kinetically arrested FMM phase can be
`recrystallized' to AFI state by annealing and more efficiently by successive
annealing, presumably by heterogeneous nucleation. This glass-like state shows
a stimulating feature that when the fraction of glass is larger the
`recrystallization' is easier.


title:
Average mass composition of primary cosmic rays in the superhigh energy
  region by Yakutsk complex EAS array data

abstract:
  The characteristics relating to the lateral and longitudinal development of
EAS in the energy region of 10^15-10^19eV have been analyzed in the framework
of the QGSJET model and of mass composition of primary cosmic rays. It is found
that at E(0) >= 5*10^15eV the mean mass composition of primary cosmic rays
begins to vary as indicated by a rise of <ln A> with increasing energy. The
maximum value of <ln A> is observed at E(0) ~ (5-50)*10^16eV. It is confirmed
by data of many compact EAS arrays and does not contradict an anomalous
diffusion model of cosmic ray propagation in our Galaxy. In the superhigh
energy region (>=10^18eV) the value <ln A> begins to decrease, i.e. the mass
composition becomes lighter and consists of protons and nuclei of He and C. It
does not contradict our earlier estimations for the mass composition and points
to a growing role of the metagalactic component of cosmic rays in the superhigh
energy region.


title: Robust model selection in generalized linear models

abstract:
  In this paper, we extend to generalized linear models (including logistic and
other binary regression models, Poisson regression and gamma regression models)
the robust model selection methodology developed by Mueller and Welsh (2005;
JASA) for linear regression models. As in Mueller and Welsh (2005), we combine
a robust penalized measure of fit to the sample with a robust measure of out of
sample predictive ability which is estimated using a post-stratified m-out-of-n
bootstrap. A key idea is that the method can be used to compare different
estimators (robust and nonrobust) as well as different models. Even when
specialized back to linear regression models, the methodology presented in this
paper improves on that of Mueller and Welsh (2005). In particular, we use a new
bias-adjusted bootstrap estimator which avoids the need to centre the
explanatory variables and to include an intercept in every model. We also use
more sophisticated arguments than Mueller and Welsh (2005) to establish an
essential monotonicity condition.


title:
Unknot diagrams requiring a quadratic number of Reidemeister moves to
  untangle

abstract:
  We present a sequence of diagrams of the unknot for which the minimum number
of Reidemeister moves required to pass to the trivial diagram is quadratic with
respect to the number of crossings. These bounds apply both in $S^2$ and in
$\R^2$.


title: A Proximal-Projection Method for Finding Zeros of Set-Valued Operators

abstract:
  In this paper we study the convergence of an iterative algorithm for finding
zeros with constraints for not necessarily monotone set-valued operators in a
reflexive Banach space. This algorithm, which we call the proximal-projection
method is, essentially, a fixed point procedure and our convergence results are
based on new generalizations of Lemma Opial. We show how the
proximal-projection method can be applied for solving ill-posed variational
inequalities and convex optimization problems with data given or computable by
approximations only. The convergence properties of the proximal-projection
method we establish also allow us to prove that the proximal point method (with
Bregman distances), whose convergence was known to happen for maximal monotone
operators, still converges when the operator involved in it is monotone with
sequentially weakly closed graph.


title: Planetary Science Goals for the Spitzer Warm Era

abstract:
  The overarching goal of planetary astronomy is to deduce how the present
collection of objects found in our Solar System were formed from the original
material present in the proto-solar nebula. As over two hundred exo-planetary
systems are now known, and multitudes more are expected, the Solar System
represents the closest and best system which we can study, and the only one in
which we can clearly resolve individual bodies other than planets. In this
White Paper we demonstrate how to use Spitzer Space Telescope InfraRed Array
Camera Channels 1 and 2 (3.6 and 4.5 um) imaging photometry with large
dedicated surveys to advance our knowledge of Solar System formation and
evolution. There are a number of vital, key projects to be pursued using
dedicated large programs that have not been pursued during the five years of
Spitzer cold operations. We present a number of the largest and most important
projects here; more will certainly be proposed once the warm era has begun,
including important observations of newly discovered objects.


title:
Effect of the steady flow on spatial damping of small-amplitude
  prominence oscillations

abstract:
  Aims. Taking account of steady flow in solar prominences, we study its
effects on spatial damping of small-amplitude non-adiabatic magnetoacoustic
waves in a homogeneous, isothermal, and unbounded prominence plasma. Methods.
We model the typical feature of observed damped oscillatory motion in
prominences, removing the adiabaticity assumption through thermal conduction,
radiation and heating. Invoking steady flow in MHD equations, we linearise them
under small-amplitude approximation and obtain a new general dispersion
relation for linear non-adiabatic magnetoacoustic waves in prominences Results.
The presence of steady flow breaks the symmetry of forward and backward
propagating MHD wave modes in prominences. The steady flow has dramatic
influence on the propagation and damping of magnetoacoustic and thermal waves.
Depending upon the direction and strength of flow the magnetoacoustic and
thermal modes can show both the features of wave amplification and damping. At
the wave period of 5 min where the photospheric power is maximum, the slow mode
shows wave amplification. However, in the absence of steady flow the slow mode
wave shows damping. Conclusions. For the wave period between 5 min and 15 min,
the amplification length for slow mode, in the case of prominence regime 1.1,
varies between 3.4*10^11 m to 2*10^12 m. Dramatic influence of steady flow on
small-amplitude prominence oscillations is likely to play an important role in
both wave detection and prominence seismology.


title: Function spaces of variable smoothness and integrability

abstract:
  In this article we introduce Triebel--Lizorkin spaces with variable
smoothness and integrability. Our new scale covers spaces with variable
exponent as well as spaces of variable smoothness that have been studied in
recent years. Vector-valued maximal inequalities do not work in the generality
which we pursue, and an alternate approach is thus developed. Applying it, we
give molecular and atomic decomposition results and show that our space is
well-defined, i.e., independent of the choice of basis functions.
  As in the classical case, a unified scale of spaces permits clearer results
in cases where smoothness and integrability interact, such as Sobolev embedding
and trace theorems. As an application of our decomposition, we prove optimal
trace theorems in the variable indices case.


title: Volume limited dependent Galactic model parameters

abstract:
  We estimated 34 sets of Galactic model parameters for three intermediate
latitude fields with Galactic longitudes l=60, l=90, and l=180, and we
discussed their dependence on the volume. Also, we confirmed the variation of
these parameters with absolute magnitude and Galactic longitude. The star
samples in two fields are restricted with bright and unit absolute magnitude
intervals, (4,5], and (5,6], whereas for the third field a larger absolute
magnitude interval is adopted, (4,10]. The limiting apparent magnitudes of star
samples are g=15 and g=22.5 mag which provide space densities within distances
in the line of sight 0.9 and 25 kpc. The Galactic model parameters for the thin
disc are not volume dependent. However, the ones for thick disc and halo do
show spectacular trends in their variations with volume, except for the
scalelength of the thick disc. The local space density of the thick disc
increases, whereas the scaleheight of the same Galactic component decreases
monotonically. However, both model parameters approach asymptotic values at
large distances. The axial ratio of the halo increases abruptly for the volumes
where thick disc is dominant, whereas it approaches an asymptotic value
gradually for larger volumes, indicating a continuous transition from disclike
structure to a spherical one at the outermost region of the Galaxy. The
variation of the Galactic model parameters with absolute magnitude can be
explained by their dependence on the stellar luminosity, whereas the variation
with volume and Galactic longitude at short distances is a bias in analysis.


title: On a Random Matrix Models of Quantum Relaxation

abstract:
  Earlier two of us (J.L. and L.P.) considered a matrix model for a two-level
system interacting with a $n\times n$ reservoir and assuming that the
interaction is modelled by a random matrix. We presented there a formula for
the reduced density matrix in the limit $n\to \infty $ as well as several its
properties and asymptotic forms in various regimes. In this paper we give the
proofs of the assertions, and present also a new fact about the model.


title: Quantum Wire as Open System

abstract:
  The faithful exchange of quantum information will soon become one of the
challenges of the emerging quantum information technology. One of the possible
solutions is to transfer a superposition through a chain of properly coupled
spins. Such a system is called a quantum wire. We discuss the transfer in a
quantum wire \cite{christ,niko1,niko2}, when the process of thermalization of
the state takes place together with the free evolution. We investigate which
encoding scheme is more faithful in certain thermal conditions.


title:
The renormalization of entanglement in the anisotropic Heisenberg (XXZ)
  model

abstract:
  We have applied our recent approach (Kargarian, et.al Phys. Rev. A 76, 60304
(R) (2007)) to study the quantum information properties of the anisotropic
s=1/2 Heisenberg chain. We have investigated the underlying quantum information
properties like the evolution of concurrence, entanglement entropy, nonanalytic
behaviours and the scaling close to the quantum critical point of the model.
Both the concurrence and the entanglement entropy develop two saturated values
after enough iterations of the renormalization of coupling constants. This
values are associated with the two different phases, i.e Neel and spin liquid
phases. The nonanalytic behaviour comes from the divergence of the first
derivative of both measures of entanglement as the size of system becomes
large. The renormalization scheme demonstrates how the minimum value of the
first derivative and its position scales with an exponent of the system size.
It is shown that this exponent is directly related to the critical properties
of the model, i.e. the exponent governing the divergence of the correlation
length close to the quantum critical point. We also use a renormalization
method based on the quantum group concept in order to get more insight about
the critical properties of the model and the renormalization of entanglement.


title: B meson spectroscopy

abstract:
  We study the $B$ meson spectroscopy allowing the mixture of conventional $P$
wave quark-antiquark states and four-quark components. A similar picture was
used to describe the new $D_J$ and $D_{sJ}$ open charm mesons. The four-quark
components shift the masses of some positive parity $B_{sJ}$ states below their
corresponding isospin preserving two-meson threshold and therefore they are
expected to be narrow. Electromagnetic decay widths are analyzed.


title:
Every longest circuit of a 3-connected, $K_{3,3}$-minor free graph has a
  chord

abstract:
  Carsten Thomassen conjectured that every longest circuit in a 3-connected
graph has a chord. We prove the conjecture for graphs having no $K_{3,3}$
minor, and consequently for planar graphs.


title: Reflection symmetry instability at high spins in 162,164Yb

abstract:
  A shape evolution of 162,164Yb in yrast states is traced using the
self-consistent Skyrme Hartree-Fock calculations. We found that nonaxial
octupole deformations (in particular, Y_{31} term) become favorable at large
rotational frequencies (> 0.4 MeV) in 162Yb, while in 164Yb a nonaxial
quadrupole shape is dominant at fast rotation. The cranked Nilsson model and
random phase approximation are used to understand the dynamics of octupole
correlations in both nuclei. We demonstrate that the disappearance of one of
the octupole vibrational modes in the rotating frame gives rise to the nonaxial
octupole deformations in 162Yb, while the octupole modes are nonzero in 164Yb.


title: How binary interactions affect spectral stellar population synthesis

abstract:
  Single-star stellar population (ssSSP) models are usually used for stellar
population studies. However, more than 50% of stars are in binaries and evolve
differently from single stars. This suggests that the effects of binary
interactions should be considered when modeling the stellar populations of
galaxies and star clusters. Via a rapid spectral stellar population synthesis
(RPS) model, we give detailed studies of the effects of binary interactions on
the Lick indices and colours of stellar populations, and on the determination
of the stellar ages and metallicities of populations.
  The results show that binary interactions make stellar populations less
luminous, bluer, with larger age-sensitive Lick index (Hbeta) and less
metallicity-sensitive indices (e.g., Mgb, Fe5270 and Fe5335) compared to
ssSSPs. It also shows that when ssSSP models are used to determine the ages and
metallicities of stellar populations, lower ages or metallicities will be
obtained, taking two line indices (Hbeta and [MgFe]) and two colours (e.g., u-R
and R-K), respectively. Some relations for linking the stellar-population
parameters obtained by ssSSPs to those obtained by binary-star stellar
populations (bsSSPs) are presented in the work. This can help us to get some
absolute values for stellar-population parameters and is useful for absolute
studies. However, it is found that the relative luminosity-weighted stellar
ages and metallicities obtained via ssSSPs and bsSSPs are similar. This
suggests that ssSSPs can be used for most stellar population studies, except in
some special cases.


title: Fluorine in R Coronae Borealis Stars

abstract:
  Neutral fluorine (F I) lines are identified in the optical spectra of several
R Coronae Borealis stars (RCBs) at maximum light. These lines provide the first
measurement of the fluorine abundance in these stars. Fluorine is enriched in
some RCBs by factors of 800 to 8000 relative to its likely initial abundance.
The overabundances of fluorine are evidence for the synthesis of fluorine.
These results are discussed in the light of the scenario that RCBs are formed
by accretion of an He white dwarf by a C-O white dwarf. Sakurai's object (V4334
Sgr), a final He-shell flash product, shows no detectable F I lines.


title: Randomness in infinitesimal extent in the McLerran-Venugopalan model

abstract:
  We study discrepancy between the analytical definition and the numerical
implementation of the McLerran-Venugopalan (MV) model. The infinitesimal extent
of a fast-moving nucleus should retain longitudinal randomness in the color
source distribution even when the longitudinal extent approximates zero due to
the Lorentz contraction, which is properly taken into account in the analytical
treatment. We point out that the longitudinal randomness is lost in numerical
simulations because of lack of the path-ordering of the Wilson line along the
longitudinal direction. We quantitatively investigate how much the results with
and without longitudinal randomness differ from each other. We finally mention
that the discrepancy could be absorbed in a choice of the model parameter in
the physical unit, and nevertheless, it is important for a full theory
approach.


title:
Interstellar 12C/13C from CH+ absorption lines: Results from an extended
  survey

abstract:
  The 12C/13C isotope ratio in the interstellar medium (ISM), and its evolution
with time, is an important tracer of stellar yields. Spatial variations of this
ratio can be used to study mixing in the ISM. We want to determine this ratio
and its spatial variations in the local ISM from CH+ absorption lines in the
optical towards early-type stars. The aim is to determine the average value for
the local ISM and study possible spatial variations. We observed a large number
of early-type stars with Feros to extend the sample of suitable target stars
for CH+ isotope studies. The best suited targets were observed with Uves with
higher signal-to-noise ratio and spectral resolution to determine the isotope
ratio from the interstellar CH+ lines. This study significantly expands the
number of 13CH+ detections. We find an average ratio of <R> = 76.27 +- 1.94 or,
for f = 1/R, <f> = (120.46 +- 3.02) 10^{-4}. The scatter in f is 6.3
sigma(<f>). This findings strengthens the case for chemical inhomogeneity in
the local ISM, with important implications for the mixing in the ISM. Given the
large scatter, the present-day value in the ISM is not significantly larger
than the solar value, which corresponds to the local value 4.5 Gyr ago.


title: Forced Convex Mean Curvature Flow in Euclidean Spaces

abstract:
  In this paper, we consider the mean curvature flow of convex hypersurfaces in
Euclidean spaces with a general forcing term. We show that the flow may shrink
to a point in finite time if the forcing term is small, or exist for all times
and expand to infinity if the forcing term is large enough. The flow can also
converge to a round sphere for some special forcing term and initial
hypersurface. Furthermore, the normalization of the flow is carried out so that
long time existence and convergence of the rescaled flow are studied. Our work
extends Huisken's well-known mean curvature flow and McCoy's mixed volume
preserving mean curvature flow.


title: An X-ray View of Radio Millisecond Pulsars

abstract:
  In recent years, X-ray observations with Chandra and XMM-Newton have
significantly increased our understanding of rotation-powered (radio)
millisecond pulsars (MSPs). Deep Chandra studies of several globular clusters
have detected X-ray counterparts to a host of MSPs, including 19 in 47 Tuc
alone. These surveys have revealed that most MSPs exhibit thermal emission from
their heated magnetic polar caps. Realistic models of this thermal X-ray
emission have provided important insight into the basic physics of pulsars and
neutron stars. In addition, intrabinary shock X-ray radiation observed in
``black-widow'' and peculiar globular cluster ``exchanged'' binary MSPs give
interesting insight into MSP winds and relativistic shock. Thus, the X-ray band
contains valuable information regarding the basic properties of MSPs that are
not accesible by radio timing observations.


title: Sending and Searching for Interstellar Messages

abstract:
  There is a close interrelation between Searching for Extraterrestrial
Intelligence (SETI) and Messaging to Extraterrestrial Intelligence (METI). For
example, the answers to the questions "Where to search" and "Where to send" are
equivalent, in that both require an identical selection from the same target
star lists. Similar considerations lead to a strategy of time synchronization
between sending and searching. Both SETI and METI use large reflectors. The
concept of "magic frequencies" may be applicable to both SETI and METI. Efforts
to understand an alien civilization's Interstellar Messages (IMs), and efforts
to compose our own IMs so they will be easily understood by unfamiliar
Extraterrestrials, are mutually complementary. Furthermore, the METI-question:
"How can we benefit from sending IMs, if a response may come only thousands of
years later?" begs an equivalent SETI-question: "How can we benefit from
searching, if it is impossible now to perceive the motivations and feelings of
those who may have sent messages in the distant past?" A joint consideration of
the theoretical and the practical aspects of both sending and searching for
IMs, in the framework of a unified, disciplined scientific approach, can be
quite fruitful. We seek to resolve the cultural disconnect between those who
advocate sending interstellar messages, and others who anathematize those who
would transmit.


title:
Observations of the Sagittarius Dwarf galaxy by the H.E.S.S. experiment
  and search for a Dark Matter signal

abstract:
  Observations of the Sagittarius dwarf spheroidal (Sgr dSph) galaxy were
carried out with the H.E.S.S. array of four imaging air Cherenkov telescopes in
June 2006. A total of 11 hours of high quality data are available after data
selection. There is no evidence for a very high energy gamma-ray signal above
the energy threshold at the target position. A 95% C.L. flux limit of 3.6 x
10-12 cm-2s-1 above 250 GeV has been derived. Constraints on the
velocity-weighted cross section <sigma v> are calculated in the framework of
Dark Matter particle annihilation using realistic models for the Dark Matter
halo profile of Sagittarius dwarf galaxy. Two different models have been
investigated encompassing a large class of halo types. A 95% C.L. exclusion
limit on <sigma v> of the order of 2 x 10-25 cm3s-1 is obtained for a core
profile in the 100 GeV - 1 TeV neutralino mass range.


title: Patterns of the Exclusive Double Diffraction

abstract:
  We consider Exclusive Double Diffractive Events (EDDE) as a powerfull tool to
study the picture of the $pp$ interaction. Calculations of the cross-sections
for the process $p+p\to p+M+p$ are presented in the convenient form for further
experimental applications. We propose measurements of t-distributions in the
joint CMS-TOTEM experiment. It is shown that important information on the
interaction region could be extracted from the diffractive pattern.


title: Representations for the non-graded Virasoro-like algebra

abstract:
  It is proved that an irreducible module over the non-graded Virasoro-like
algebra, which satisfies a natural condition, is a GHW module or uniformly
bounded. Furthermore, the classification of some uniformly bounded modules is
given.


title: Braid groups and Artin groups

abstract:
  This article is a survey on the braid groups, the Artin groups, and the
Garside groups. It is a presentation, accessible to non-experts, of various
topological and algebraic aspects of these groups. It is also a report on three
points of the theory: the faithful linear representations, the cohomology, and
the geometrical representations.


title: Urn-related random walk with drift $\rho x^{\alpha} / t^{\beta}$

abstract:
  We study a one-dimensional random walk whose expected drift depends both on
time and the position of a particle. We establish a non-trivial phase
transition for the recurrence vs. transience of the walk, and show some
interesting applications to Friedman's urn, as well as showing the connection
with Lamperti's walk with asymptotically zero drift.


title:
Describing the set of words generated by interval exchange
  transformation

abstract:
  Let $W$ be an infinite word over finite alphabet $A$. We get combinatorial
criteria of existence of interval exchange transformations that generate the
word W.


title: The induced capacity and Choquet integral monotone convergece

abstract:
  Given a probability measure over a state space, a partial collection
(sub-$\sigma$-algebra) of events whose probabilities are known, induces a
capacity over the collection of all possible events. The \emph{induced
capacity} of an event $F$ is the probability of the maximal (with respect to
inclusion) event contained in $F$ whose probability is known. The Choquet
integral with respect to the induced capacity coincides with the integral with
respect to a \emph{probability specified on a sub-algebra} (Lehrer
\cite{Lehrer2}). We study Choquet integral monotone convergence and apply the
results to the integral with respect to the induced capacity. The paper
characterizes the properties of sub-$\sigma$-algebras and of induced capacities
which yield integral monotone convergence.