title:
A Catalog of Broad Absorption Line Quasars in Sloan Digital Sky Survey
  Data Release 5

abstract:
  We present a catalog of 5039 broad absorption line (BAL) quasars (QSOs) in
the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have
absorption troughs covering a continuous velocity range >= 2000 km/s. We have
fit ultraviolet (UV) continua and line emission in each case, enabling us to
report common diagnostics of BAL strengths and velocities in the range -25,000
to 0 km/s for SiIV $\lambda$1400, CIV $\lambda$1549, AlIII $\lambda$1857, and
MgII $\lambda$2799. We calculate these diagnostics using the spectrum listed in
the DR5 QSO catalog, and also for spectra from additional SDSS observing epochs
when available. In cases where BAL QSOs have been observed with Chandra or
XMM-Newton, we report the X-ray monochromatic luminosities of these sources.
  We confirm and extend previous findings that BAL QSOs are more strongly
reddened in the rest-frame UV than non-BAL QSOs and that BAL QSOs are
relatively X-ray weak compared to non-BAL QSOs. The observed BAL fraction is
dependent on the spectral signal-to-noise (S/N); for higher-S/N sources, we
find an observed BAL fraction of approximately 15%. BAL QSOs show a similar
Baldwin effect as for non-BAL QSOs, in that their CIV emission equivalent
widths decrease with increasing continuum luminosity. However, BAL QSOs have
weaker CIV emission in general than do non-BAL QSOs. Sources with higher UV
luminosities are more likely to have higher-velocity outflows, and the BAL
outflow velocity and UV absorption strength are correlated with relative X-ray
weakness. These results are in qualitative agreement with models that depend on
strong X-ray absorption to shield the outflow from over-ionization and enable
radiative acceleration....


title: Near-IR Subwavelength Microdisk Lasers

abstract:
  We report single-mode lasing in subwavelength GaAs disks under optical
pumping. The disks are fabricated by standard photolithography and two steps of
wet chemical etching. The simple fabrication method can produce submicron disks
with good circularity, smooth boundary and vertical sidewalls. The smallest
lasing disks have a diameter of 627 nm and thickness of 265 nm. The ratio of
the disk diameter to the vacuum lasing wavelength is about 0.7. Our numerical
simulations confirm that the lasing modes are whispering-gallery modes with the
azimuthal number as small as 4 and very small mode volume.


title:
Sequential Desynchronization in Networks of Spiking Neurons with Partial
  Reset

abstract:
  The response of a neuron to synaptic input strongly depends on whether or not
it has just emitted a spike. We propose a neuron model that after spike
emission exhibits a partial response to residual input charges and study its
collective network dynamics analytically. We uncover a novel desynchronization
mechanism that causes a sequential desynchronization transition: In globally
coupled neurons an increase in the strength of the partial response induces a
sequence of bifurcations from states with large clusters of synchronously
firing neurons, through states with smaller clusters to completely asynchronous
spiking. We briefly discuss key consequences of this mechanism for more general
networks of biophysical neurons.


title: Rank one perturbations and singular integral operators

abstract:
  We consider rank one perturbations $A_\alpha=A+\alpha(\cdot,\varphi)\varphi$
of a self-adjoint operator $A$ with cyclic vector $\varphi\in\mathcal
H_{-1}(A)$ on a Hilbert space $\mathcal H$. The spectral representation of the
perturbed operator $A_\alpha$ is given by a singular integral operator of
special form. Such operators exhibit what we call 'rigidity' and are connected
with two weight estimates for the Hilbert transform.
  Also, some results about two weight estimates of Cauchy (Hilbert) transforms
are proved. In particular, it is proved that the regularized Cauchy transforms
$T_\varepsilon$ are uniformly (in $\varepsilon$) bounded operators from
$L^2(\mu)$ to $L^2(\mu_\alpha)$, where $\mu$ and $\mu_\alpha$ are the spectral
measures of $A$ and $A_\alpha$, respectively.
  As an application, a sufficient condition for $A_\alpha$ to have a pure
absolutely continuous spectrum on a closed interval is given in terms of the
density of the spectral measure of $A$ with respect to $\varphi$. Some
examples, like Jacobi matrices and Schr\"odinger operators with $L^2$
potentials are considered.


title: The noncommutative Choquet boundary II: Hyperrigidity

abstract:
  A (finite or countably infinite) set G of generators of an abstract
C*-algebra A is called hyperrigid if for every faithful representation of A on
a Hilbert space $A\subseteq \mathcal B(H)$ and every sequence of unital
completely positive linear maps $\phi_1, \phi_2,...$ from $\mathcal B(H)$ to
itself,
  $$ \lim_{n\to\infty}\|\phi_n(g)-g\|=0, \forall g\in G \implies
\lim_{n\to\infty}\|\phi_n(a)-a\|=0, \forall a\in A. $$
  We show that one can determine whether a given set G of generators is
hyperrigid by examining the noncommutative Choquet boundary of the operator
space spanned by $G\cup G^*$. We present a variety of concrete applications and
discuss prospects for further development.


title:
Lienard-Wiechert Potentials and the Method of Images in an RF Free
  Electron Laser Photoinjector

abstract:
  Based on Lienard-Weichert retarded potentials and the potential due to the
image of charges on the cathode, a rigorous relativistic description of the
beam transport inside the RF-photoinjector is presented. The velocity dependent
effects are taken into account. Simulations are presented for parameters of the
"ELSA" photo-cathode


title:
Concentration of the spectral measure of large Wishart matrices with
  dependent entries

abstract:
  We derive concentration inequalities for the spectral measure of large random
matrices, allowing for certain forms of dependence. Our main focus is on
empirical covariance (Wishart) matrices, but general symmetric random matrices
are also considered.


title:
Phase portraits for quadratic homogeneous polynomial vector fields on
  S^2

abstract:
  Let X be a homogeneous polynomial vector field of degree 2 on S^2. We show
that if X has at least a non--hyperbolic singularity, then it has no limit
cycles. We give necessary and sufficient conditions for determining if a
singularity of X on S^2 is a center and we characterize the global phase
portrait of X modulo limit cycles. We also study the Hopf bifurcation of X and
we reduce the 16^{th} Hilbert's problem restricted to this class of polynomial
vector fields to the study of two particular families. Moreover, we present two
criteria for studying the nonexistence of periodic orbits for homogeneous
polynomial vector fields on S^2 of degree n.


title:
Solar neutrino variability and its implications for solar physics and
  neutrino physics

abstract:
  Recent coordinated power-spectrum analyses of radiochemical solar neutrino
data and the solar irradiance have revealed a highly significant, high-Q common
modulation at 11.85 yr-1. Since the stability of this frequency points to an
explanation in terms of rotation, this result may be attributable to
non-spherically-symmetric nuclear burning in a solar core with sidereal
rotation frequency 12.85 yr-1. The variability of the amplitude (on a timescale
of years) suggests that the relevant nuclear burning is variable as well as
asymmetric. Recent analysis of Super-Kamiokande solar neutrino data has
revealed r-mode-type modulations with frequencies corresponding to a region
with sidereal rotation frequency 13.97 yr-1. If this modulation is attributed
to the RSFP (Resonant Spin Flavor Precession) process, it provides a
measurement of the rotation rate deep in the radiative zone. These two results
suggest that the core rotates significantly more slowly than the radiative
zone. If one accepts an upper limit of 7 MG for the Sun's internal magnetic
field, an RSFP interpretation of the Super-Kamiokande results leads to a lower
limit of 10-12 Bohr magnetons for the neutrino transition magnetic moment.


title:
The prospects for a new search for the electron electric dipole moment
  in solid Gadolinium iron garnet ceramics

abstract:
  We address a number of issues regarding solid state electron electric dipole
moment (EDM) experiments, focusing on gadolinium iron garnet (abbreviated GdIG,
chemical formula Gd$_3$Fe$_5$O$_{12}$) as a possible sample material. GdIG
maintains its high magnetic susceptibility down to 4.2 K, which enhances the
EDM-induced magnetization of a sample placed in an electric field. We estimate
that lattice polarizability gives rise to an EDM enhancement factor of
approximately 20. We also calculate the effect of the demagnetizing field for
various sample geometries and permeabilities. Measurements of intrinsic GdIG
magnetization noise are presented, and the fluctuation-dissipation theorem is
used to compare our data with the measurements of the imaginary part of GdIG
permeability at 4.2 K, showing good agreement above frequencies of a few hertz.
We also observe how the demagnetizing field suppresses the noise-induced
magnetic flux, confirming our calculations. The statistical sensitivity of an
EDM search based on a solid GdIG sample is estimated to be on the same level as
the present experimental limit. Such a measurement would be valuable, given the
completely different methods and systematics involved. The most significant
systematics in such an experiment are the magnetic hysteresis and the
magneto-electric effect. Our analysis shows that it should be possible to
control these at the level of statistical sensitivity.


title: Beam dynamics and wake-field simulations for the CLIC main linacs

abstract:
  The CLIC linear collider aims at accelerating multiple bunches of electrons
and positrons and colliding them at a centre of mass energy of 3 TeV. These
bunches will be accelerated through X-band linacs, operating at an accelerating
frequency of 12 GHz. Each beam readily excites wake-fields within the
accelerating cavities of each linac. The transverse components of the
wake-fields, if left unchecked, can dilute the beam emittance. The present CLIC
design relies on heavy damping of these wake-fields in order to ameliorate the
effects of the wake-fields on the beam emittance. Here we present initial
results on simulations of the long-range wake-fields in these structures and on
beam dynamics simulations. In particular, detailed simulations are performed,
on emittance dilution due to beams initially injected with realistic offsets
from the electrical centre of the cavities.


title:
Optimal covariant measurements: the case of a compact symmetry group and
  phase observables

abstract:
  We study various optimality criteria for quantum observables. Observables are
represented as covariant positive operator valued measures and we consider the
case when the symmetry group is compact. Phase observables are examined as an
example.


title:
Excitation of a bosonic mode by electron tunneling into a cuprate
  superconductor

abstract:
  We performed scanning tunneling spectroscopic experiments on hole-doped
NdBa$_2$Cu$_3$O$_{7-\delta}$. The d$I$/d$V$ curves obtained at 4.2 K are
asymmetric with clear peak-dip and hump structures. Energy derivatives of these
curves show peaks at energies beyond the dip features. Highly precise full
potential bandstructure calculations confirm a featureless electronic density
of states in that energy region. Our results indicate that tunneling electrons
couple to a collective mode in the CuO$_2$ plane.


title:
Slowly replicating lytic viruses: pseudolysogenic persistence and
  within-host competition

abstract:
  We study the population dynamics of lytic viruses which replicate slowly in
dividing host cells within an organism or cell culture, and find a range of
viral replication rates that allows viruses to persist, avoiding extinction of
host cells or dilution of viruses at too rapid or too slow viral replication.
For the within-host competition between multiple viral strains, a strain with a
"stable" replication rate could outcompete another strain with a higher or
lower replication rate, therefore natural selection of viruses stabilizes the
viral persistence. However, when strains with higher and lower than the
"stable" value replication rates are both present, competition between strains
does not result in dominance of one strain, but in their coexistence.


title: Noncommutative localization in algebraic $L$-theory

abstract:
  Given a noncommutative (Cohn) localization $A \to \sigma^{-1}A$ which is
injective and stably flat we obtain a lifting theorem for induced f.g.
projective $\sigma^{-1}A$-module chain complexes and localization exact
sequences in algebraic $L$-theory, matching the algebraic $K$-theory
localization exact sequence of Neeman and Ranicki.


title: One-loop amplitudes for W+3 jet production in hadron collisions

abstract:
  We employ the recently developed method of generalized $D$-dimensional
unitarity to compute one-loop virtual corrections to all scattering amplitudes
relevant for the production of a $W$ boson in association with three jets in
hadronic collisions, treating all quarks as massless.


title:
Scattering matrix simulations of fields and dispersion relations in
  superconducting cavities for XFEL and ILC

abstract:
  The globalised cascaded scattering matrix technique is a well proven,
practical method that can be used to simulate large accelerating RF structures
in which realistic fabrication errors to be incorporated in an efficient manner
without the necessity to re-mesh the entire geometry. The globalised scattering
matrix (GMS) technique allows one to obtain the scattering matrix for a
structure. The method allows rapid e.m. field calculations to be obtained.
Results are presented on monopole mode fields and dispersion relations
calculated from direct and analytical methods. Analytical approximate results
are also presented for the equivalent shunt susceptance of an iris loaded
structure.


title:
A Simple Linear Ranking Algorithm Using Query Dependent Intercept
  Variables

abstract:
  The LETOR website contains three information retrieval datasets used as a
benchmark for testing machine learning ideas for ranking. Algorithms
participating in the challenge are required to assign score values to search
results for a collection of queries, and are measured using standard IR ranking
measures (NDCG, precision, MAP) that depend only the relative score-induced
order of the results. Similarly to many of the ideas proposed in the
participating algorithms, we train a linear classifier. In contrast with other
participating algorithms, we define an additional free variable (intercept, or
benchmark) for each query. This allows expressing the fact that results for
different queries are incomparable for the purpose of determining relevance.
The cost of this idea is the addition of relatively few nuisance parameters.
Our approach is simple, and we used a standard logistic regression library to
test it. The results beat the reported participating algorithms. Hence, it
seems promising to combine our approach with other more complex ideas.


title: Beam dynamics and wake-field simulations for high gradient ILC linacs

abstract:
  Higher order modes (HOMs) are simulated with finite element and finite
difference computer codes for the ILC superconducting cavities. In particular,
HOMs in KEK's Ichiro type of cavity and Cornell University's Reentrant design
are focused on in this work. The aim, at these universities and laboratories,
is to achieve an accelerating gradient in excess of 50 MV/m in 9-cell
superconducting cavities whilst maintaining a high quality and stable electron
beam. At these gradients, electrical breakdown is an important cause for
concern and the wakefields excited by the energetic electron beams are also
potentially damaging to the beam's emittance. Here we restrict the analysis to
performing detailed simulations, on emittance dilution due to beams initially
injected with realistic offsets from the electrical centre of the cavities. We
take advantage of the latest beam dynamics codes in order to perform these
simulations.


title: Schlesinger transformations for algebraic Painleve VI solutions

abstract:
  Various Schlesinger transformations can be combined with a direct pull-back
of a hypergeometric 2x2 system to obtain $RS^2_4$-pullback transformations to
isomonodromic 2x2 Fuchsian systems with 4 singularities. The corresponding
Painleve VI solutions are algebraic functions, possibly in different orbits
under Okamoto transformations. This paper demonstrates a direct computation of
Schlesinger transformations acting on several apparent singular points, and
presents an algebraic procedure (via syzygies) of computing algebraic Painleve
VI solutions without deriving full RS-pullback transformations.


title: Wreath Hecke algebras and centralizer construction for wreath products

abstract:
  Generalizing the centralizer construction of Molev and Olshanski on symmetric
groups, we study the structures of the centralizer $\mZ_{m,n}$ of the wreath
product $G_{n-m}$ in the group algebra of $G_n$ for any $n\geq m$. We establish
the connection between $\mZ_{m,n}$ and a generalization of degenerate affine
Hecke algebras introduced in our earlier work.


title: Fusion rules and four-point functions in the AdS3 WZNW model

abstract:
  We study the operator product expansion in the AdS$_3$ WZNW model. The OPE of
primary fields and their spectral flow images is computed from the analytic
continuation of the expressions in the H$_3^+$ WZNW model, adding spectral
flow. We argue that the symmetries of the affine algebra require a truncation
which establishes the closure of the fusion rules on the Hilbert space of the
theory. Although the physical mechanism determining the decoupling is not
completely understood, we present several consistency checks on the results. A
preliminary analysis of factorization allows to obtain some properties of
four-point functions involving fields in generic sectors of the theory, to
verify that they agree with the spectral flow selection rules and to show that
the truncation must be realized in physical amplitudes for consistency.


title: DMTPC-10L: Direction-Sensitive Dark Matter Detector Prototype

abstract:
  The known direction of motion of dark matter particles relative to the Earth
may be a key for their unambiguous identification even in the presence of
backgrounds. We describe a prototype detector that is able to reconstruct
direction vectors of weakly interacting massive particles that may the dominant
constituent of the dark matter in our galaxy. The detector uses a low-density
gas (CF4) in a 10liter time-projection chamber with mesh-based electrodes and
optical and charge readout. Initial results confirm good performance in the
reconstruction of direction angle and sense ('head-tail') for low-momentum
nuclear recoils.


title:
Magnetic susceptibility and magnetization fluctuation measurements of
  mixed Gadolinium-Yttrium Iron Garnets

abstract:
  We study the magnetic properties of Gadolinium-Yttrium Iron Garnet
($\text{Gd}_{x}\text{Y}_{3-x}\text{Fe}_5\text{0}_{12}$, $x=3,1.8$) ferrite
ceramics. The complex initial permeability is measured in the temperature range
2 K to 295 K at frequency of 1 kHz, and in the frequency range 100 Hz to 200
MHz at temperatures 4 K, 77 K, and 295 K. The magnetic viscosity-induced
imaginary part of the permeability is observed at low frequencies. Measurements
of the magnetization noise are made at 4 K. Using the fluctuation-dissipation
theorem, we find that the observed magnetization fluctuations are consistent
with our measurements of the low-frequency imaginary part of permeability. We
discuss some implications for proposed precision measurements as well as other
possible applications.


title:
LU-decomposition of a noncommutative linear system and Jacobi
  polynomials

abstract:
  In this paper we obtain the LU-decomposition of a noncommutative linear
system of equations that, in the rank one case, characterizes the image of the
Lepowsky homomorphism $U(\lieg)^{K}\to U(\liek)^{M}\otimes U(\liea)$. This
LU-decomposition can be transformed into very simple matrix identities, where
the entries of the matrices involved belong to a special class of Jacobi
polynomials. In particular, each entry of the L part of the original system is
expressed in terms of a single ultraspherical Jacobi polynomial. In turns,
these matrix identities yield a biorthogonality relation between the
ultraspherical Jacobi polynomials.


title:
Inversion of specific heat oscillations with in-plane magnetic field
  angle in 2D d-wave superconductors

abstract:
  Experiments on several novel superconducting compounds have observed
oscillations of the specific heat when an applied magnetic field is rotated
with respect to the crystal axes. The results are commonly interpreted as
arising from the nodes of an unconventional order parameter, but the
identifications of nodal directions are sometimes controversial. Here we show
with a semiclassical model calculation that when the magnetic field points in
the direction of the nodes, either minima or maxima can occur in the specific
heat depending on the the temperature $T$ and the magnetic field $H$. An
inversion of the angular oscillations takes place with respect to those
predicted earlier at low temperature by the nodal approximation.
  This result, together with the argument that the inversion takes place based
on an approximation valid at moderate fields, indicates that the inversion of
specific heat oscillations is an intrinsic feature of nodal superconductors.


title: A note on quasi-Gorenstein rings

abstract:
  In this paper, after giving a criterion for a Noetherian local ring to be
quasi-Gorenstein, we obtain some sufficient conditions for a quasi- Gorenstein
ring to be Gorenstein. In the course, we provide a slight generalization of a
theorem of Evans and Griffith.


title:
Two-pion-exchange and other higher-order contributions to the $pp\to
  pp\pi^0$ reaction

abstract:
  Much effort has been invested on effective-field-theoretical studies of the
near-threshold NN \to NN\pi reactions and, in order to deal with the rather
large three-momentum transfers involved, the momentum counting scheme was
proposed as an alternative to the usual Weinberg counting scheme. To examine
the practical utility of the momentum counting scheme, we study here the
contributions of higher-order terms to the pp\to pp\pi^0 reaction. We discuss
the consequences of the different treatments of the nucleon propagators in
these two counting schemes. We also investigate certain higher chiral-order
pion-rescattering terms and the five-point counter-term, which turn out to give
important contributions.


title: Synchronization Stability of Coupled Near-Identical Oscillator Network

abstract:
  We derive variational equations to analyze the stability of synchronization
for coupled near-identical oscillators. To study the effect of parameter
mismatch on the stability in a general fashion, we define master stability
equations and associated master stability functions, which are independent of
the network structure. In particular, we present several examples of coupled
near-identical Lorenz systems configured in small networks (a ring graph and
sequence networks) with a fixed parameter mismatch and a large Barabasi-Albert
scale-free network with random parameter mismatch. We find that several
different network architectures permit similar results despite various mismatch
patterns.


title: Dopplera efiko de luma ebeno vidata per akcelata observanto

abstract:
  A plane lights on monochromatically and immediately after lights off, while
an observer starts moving out from the plane, perpendicularly to it, with
constant proper acceleration. Special relativity predicts that the observer
will see a light circle always in the direction opposite to the plane, without
Doppler effect, and that the circle will seem to progressively shrink to a
point.
  -----
  Ebeno eklumi^gas unukolore kaj tuj poste mallumi^gas, dum observanto
ekmovi^gas orte el ebeno kun konstanta propra akcelo. Special-relativeco
anta^udiras, ke observanto vidos luman cirklon ^ciam en direkto mala al la
ebeno, sen Dopplera efiko, kaj ke tiu cirklo ^sajnos progrese eti^gi ^gis
punkto.


title: Yet another look at Harris' ergodic theorem for Markov chains

abstract:
  The aim of this note is to present an elementary proof of a variation of
Harris' ergodic theorem of Markov chains. This theorem, dating back to the
fifties essentially states that a Markov chain is uniquely ergodic if it admits
a ``small'' set which is visited infinitely often. This gives an extension of
the ideas of Doeblin to the unbounded state space setting. Often this is
established by finding a Lyapunov function with ``small'' level sets. This
topic has been studied by many authors (cf. Harris, Hasminskii, Nummelin, Meyn
and Tweedie). If the Lyapunov function is strong enough, one has a spectral gap
in a weighted supremum norm (cf. Meyn and Tweedie).
  Traditional proofs of this result rely on the decomposition of the Markov
chain into excursions away from the small set and a careful analysis of the
exponential tail of the length of these excursions. There have been other
variations which have made use of Poisson equations or worked at getting
explicit constants. The present proof is very direct, and relies instead on
introducing a family of equivalent weighted norms indexed by a parameter
$\beta$ and to make an appropriate choice of this parameter that allows to
combine in a very elementary way the two ingredients (existence of a Lyapunov
function and irreducibility) that are crucial in obtaining a spectral gap.
  The original motivation of this proof was the authors' work on spectral gaps
in Wasserstein metrics. The proof presented in this note is a version of our
reasoning in the total variation setting which we used to guide the
calculations in arXiv:math/0602479. While we initially produced it for that
purpose, we hope that it will be of interest in its own right.


title: On Universality of Ergoregion Mergers

abstract:
  We study mergers of ergoregions in $d+1$-dimensional vacuum gravity. At the
merger point, where the ergosurfaces bounding each ergoregion just touch,
solutions exhibit universal behavior when there is rotation only in one plane:
the angle between the merging ergosurfaces depends only on the symmetries of
the solution, not on any other details of the configuration. We show that
universality follows from the fact that the relevant component of Einstein's
equation reduces to Laplace equation at the point of merger. Thus ergoregion
mergers mimic mergers of Newtonian equipotentials and have similar universal
behavior. For solutions with rotation in more than one plane, universality is
lost. We demonstrate universality and non-universality in several explicit
examples.


title:
Magnetohydrodynamic Effects in Propagating Relativistic Jets: Reverse
  Shock and Magnetic Acceleration

abstract:
  We solve the Riemann problem for the deceleration of an arbitrarily
magnetized relativistic flow injected into a static unmagnetized medium in one
dimension. We find that for the same initial Lorentz factor, the reverse shock
becomes progressively weaker with increasing magnetization \sigma (the
Poynting-to kinetic energy flux ratio), and the shock becomes a rarefaction
wave when \sigma exceeds a critical value, \sigma_c, defined by the balance
between the magnetic pressure in the flow and the thermal pressure in the
forward shock. In the rarefaction wave regime, we find that the rarefied region
is accelerated to a Lorentz factor that is significantly larger than the
initial value. This acceleration mechanism is due to the strong magnetic
pressure in the flow. We discuss the implications of these results for models
of gamma-ray bursts and active galactic nuclei.


title: Universal quantum computation in a hidden basis

abstract:
  Let $\ket{\0}$ and $\ket{\1}$ be two states that are promised to come from
known subsets of orthogonal subspaces, but are otherwise unknown. Our paper
probes the question of what can be achieved with respect to the basis
$\{\ket{\0},\ket{\1}}^{\otimes n}$ of $n$ logical qubits, given only a few
copies of the unknown states $\ket{\0}$ and $\ket{\1}$. A phase-invariant
operator is one that is unchanged under the relative phase-shift $\ket{\1}
\mapsto e^{i \theta}\ket{\1}$, for any $\theta$, of all of the $n$ qubits. We
show that phase-invariant unitary operators can be implemented exactly with no
copies and that phase-invariant states can be prepared exactly with at most $n$
copies each of $\ket{\0}$ and $\ket{\1}$; we give an explicit algorithm for
state preparation that is efficient for some classes of states (e.g. symmetric
states). We conjecture that certain non-phase-invariant operations are
impossible to perform accurately without many copies. Motivated by optical
implementations of quantum computers, we define ``quantum computation in a
hidden basis'' to mean executing a quantum algorithm with respect to the
phase-shifted hidden basis $\{\ket{\0}, e^{i\theta}\ket{\1}\}$, for some
potentially unknown $\theta$; we give an efficient approximation algorithm for
this task, for which we introduce an analogue of a coherent state of light,
which serves as a bounded quantum phase reference frame encoding $\theta$. Our
motivation was quantum-public-key cryptography, however the techniques are
general. We apply our results to quantum-public-key authentication protocols,
by showing that a natural class of digital signature schemes for classical
messages is insecure. We also give a protocol for identification that uses many
of the ideas discussed and whose security relates to our conjecture (but we do
not know if it is secure).


title: Linear Time Encoding of LDPC Codes

abstract:
  In this paper, we propose a linear complexity encoding method for arbitrary
LDPC codes. We start from a simple graph-based encoding method
``label-and-decide.'' We prove that the ``label-and-decide'' method is
applicable to Tanner graphs with a hierarchical structure--pseudo-trees-- and
that the resulting encoding complexity is linear with the code block length.
Next, we define a second type of Tanner graphs--the encoding stopping set. The
encoding stopping set is encoded in linear complexity by a revised
label-and-decide algorithm--the ``label-decide-recompute.'' Finally, we prove
that any Tanner graph can be partitioned into encoding stopping sets and
pseudo-trees. By encoding each encoding stopping set or pseudo-tree
sequentially, we develop a linear complexity encoding method for general LDPC
codes where the encoding complexity is proved to be less than $4 \cdot M \cdot
(\overline{k} - 1)$, where $M$ is the number of independent rows in the parity
check matrix and $\overline{k}$ represents the mean row weight of the parity
check matrix.


title:
Submillimeter water and ammonia absorption by the peculiar z~0.89
  interstellar medium in the gravitational lens of the PKS 1830-211 system

abstract:
  Using the Atacama Pathfinder Experiment (APEX) telescope we have detected the
rotational ground-state transitions of ortho-ammonia and ortho-water toward the
redshift ~0.89 absorbing galaxy in the PKS 1830-211 gravitational lens system.
We discuss our observations in the context of recent space-borne data obtained
for these lines with the SWAS and Odin satellites toward Galactic sources. We
find commonalities, but also significant differences between the interstellar
media in a galaxy at intermediate redshift and in the Milky Way. Future
high-quality observations of the ground-state ammonia transition in PKS
1830-211, together with inversion line data, will lead to strong constraints on
the variation of the proton to electron mass ratio over the past 7.2 Gyr.


title: Long-time Protection of Nonlocal Entanglement

abstract:
  We investigate how nonlocal entanglement, as identified by violations of a
Bell inequality, may be protected during the evolution. Our system consists of
two qubits each embedded in a bosonic reservoir evolving independently and
initially in an entangled mixed state. We show that the violation of the Bell
inequality can be related to the single-qubit population of excited state in
such a way that, by appropriately choosing structured environments that give
rise to sufficiently high values of population trapping, long-time protection
of nonlocal entanglement can be correspondingly achieved.


title: TeV Gamma Rays from Geminga and the Origin of the GeV Positron Excess

abstract:
  The Geminga pulsar has long been one of the most intriguing MeV-GeV gamma-ray
point sources. We examine the implications of the recent Milagro detection of
extended, multi-TeV gamma-ray emission from Geminga, finding that this reveals
the existence of an ancient, powerful cosmic-ray accelerator that can plausibly
account for the multi-GeV positron excess that has evaded explanation. We
explore a number of testable predictions for gamma-ray and electron/positron
experiments (up to ~100 TeV) that can confirm the first "direct" detection of a
cosmic-ray source.


title:
The Destruction of Thin Stellar Disks Via Cosmologically Common
  Satellite Accretion Events

abstract:
  Most Galaxy-sized systems (M_host ~ 10^12 M_sun) in the LCDM cosmology are
expected to have accreted at least one satellite with a total mass M_sat ~
10^11 M_sun = 3M_disk in the past 8 Gyr. Analytic and numerical investigations
suggest that this is the most precarious type of merger for the survival of
thin galactic disks because more massive accretion events are relatively rare
and less massive ones preserve thin disk components. We use high-resolution,
dissipationless N-body simulations to study the response of an initially-thin,
fully-formed Milky-Way type stellar disk to these cosmologically common events
and show that the thin disk does not survive. Regardless of orbital
configuration, the impacts transform the disks into structures that are roughly
three times as thick and more than twice as kinematically hot as the observed
dominant thin disk component of the Milky Way. We conclude that if the Galactic
thin disk is a representative case, then the presence of a stabilizing gas
component is the only recourse for explaining the preponderance of disk
galaxies in an LCDM universe; otherwise, the disk of the Milky Way must be
uncommonly cold and thin for its luminosity, perhaps as a consequence of an
unusually quiescent accretion history.


title: Relativistic Bohmian mechanics from scalar gravity

abstract:
  In this article we show that the fundamental equations of relativistic
Bohmian mechanics for a single particle can be derived from a scalar theory of
curved space-time.


title: Testing Inflation: A Bootstrap Approach

abstract:
  We note that the essential idea of inflation, that the universe underwent a
brief period of accelerated expansion followed by a long period of decelerated
expansion, can be encapsulated in a "closure condition" which relates the
amount of accelerated expansion during inflation to the amount of decelerated
expansion afterward. We present a protocol for systematically testing the
validity of this condition observationally.


title:
A Steep Faint-End Slope of the UV Luminosity Function at z~2-3:
  Implications for the Global Stellar Mass Density and Star Formation in Low
  Mass Halos

abstract:
  We use the deep ground-based optical photometry of the Lyman Break Galaxy
(LBG) Survey to derive robust measurements of the faint-end slope (alpha) of
the UV LF at redshifts 1.9<z<3.4. Our sample includes >2000 spectroscopic
redshifts and ~31000 LBGs in 31 spatially-independent fields over a total area
of 3261 arcmin^2. These data allow us to select galaxies to 0.07L* and 0.10L*
at z~2 and z~3, respectively. A maximum likelihood analysis indicates steep
values of alpha(z=2)=-1.73+/-0.07 and alpha(z=3)=-1.73+/-0.13. This result is
robust to luminosity dependent systematics in the Ly-alpha equivalent width and
reddening distributions, is similar to the steep values advocated at z>4, and
implies that ~93% of the unobscured UV luminosity density at z~2-3 arises from
sub-L* galaxies. With a realistic luminosity dependent reddening distribution,
faint to moderately luminous galaxies account for >70% and >25% of the
bolometric luminosity density and present-day stellar mass density,
respectively, when integrated over 1.9<z<3.4. We find a factor of 8-9 increase
in the star formation rate density between z~6 and z~2, due to both a
brightening of L* and an increasing dust correction proceeding to lower
redshifts. The previously observed discrepancy between the integral of the star
formation history and stellar mass density measurements at z~2 may be
reconciled by invoking a luminosity dependent reddening correction to the star
formation history combined with an accounting for the stellar mass contributed
by UV-faint galaxies. The steep and relatively constant alpha of the UV LF at
z>2 contrasts with the shallower value inferred locally, suggesting that the
evolution in the faint-end slope may be dictated simply by the availability of
low mass halos capable of supporting star formation at z<2. [Abridged]


title: Coset bounds for algebraic geometric codes

abstract:
  For a given curve X and divisor class C, we give lower bounds on the degree
of a divisor A such that A and A-C belong to specified semigroups of divisors.
For suitable choices of the semigroups we obtain (1) lower bounds for the size
of a party A that can recover the secret in an algebraic geometric linear
secret sharing scheme with adversary threshold C, and (2) lower bounds for the
support A of a codeword in a geometric Goppa code with designed minimum support
C. Our bounds include and improve both the order bound and the floor bound. The
bounds are illustrated for two-point codes on general Hermitian and Suzuki
curves.


title:
Shells, jets, and internal working surfaces in the molecular outflow
  from IRAS 04166+2706

abstract:
  Context: IRAS 04166+2706 in Taurus is one of the most nearby young stellar
objects whose molecular outflow contains a highly collimated fast component.
  Methods: We have observed the IRAS 04166+2706 outflow with the IRAM Plateau
de Bure interferometer in CO(J=2-1) and SiO(J=2-1) achieving angular
resolutions between 2'' and 4''. To improve the quality of the CO(2-1) images,
we have added single dish data to the interferometer visibilities.
  Results: The outflow consists of two distinct components. At velocities <10
km/s, the gas forms two opposed, approximately conical shells that have the YSO
at their vertex. These shells coincide with the walls of evacuated cavities and
seem to result from the acceleration of the ambient gas by a wide-angle wind.
At velocities >30 km/s, the gas forms two opposed jets that travel along the
center of the cavities and whose emission is dominated by a symmetric
collection of at least 7 pairs of peaks. The velocity field of this component
presents a sawtooth pattern with the gas in the tail of each peak moving faster
than the gas in the head. This pattern, together with a systematic widening of
the peaks with distance to the central source, is consistent with the emission
arising from internal working surfaces traveling along the jet and resulting
from variations in the velocity field of ejection. We interpret this component
as the true protostellar wind, and we find its composition consistent with a
chemical model of such type of wind.
  Conclusions: Our results support outflow wind models that have simultaneously
wide-angle and narrow components, and suggest that the EHV peaks seen in a
number of outflows consist of internally-shocked wind material.


title: Simulating the formation of a proto-cluster at z~2

abstract:
  We present results from two high-resolution hydrodynamical simulations of
proto-cluster regions at z~2.1. The simulations have been compared to
observational results for the socalled Spiderweb galaxy system, the core of a
putative proto-cluster region at z = 2.16, found around a radio galaxy. The
simulated regions have been chosen so as to form a poor cluster with M200~10^14
h-1 Msun (C1) and a rich cluster with M200~2x10^15 h-1 Msun (C2) at z = 0. The
simulated proto-clusters show evidence of ongoing assembly of a dominating
central galaxy. The stellar mass of the brightest cluster galaxy (BCG) of the
C2 system is in excess with respect to observational estimates for the
Spiderweb galaxy, with a total star formation rate which is also larger than
indicated by observations. We find that the projected velocities of galaxies in
the C2 cluster are consistent with observations, while those measured for the
poorer cluster C1 are too low compared to the observed velocities. We argue
that the Spiderweb complex resemble the high-redshift progenitor of a rich
galaxy cluster. Our results indicate that the included supernovae feedback is
not enough to suppress star formation in these systems, supporting the need of
introducing AGN feedback. According to our simulations, a diffuse atmosphere of
hot gas in hydrostatic equilibrium should already be present at this redshift,
and enriched at a level comparable to that of nearby galaxy clusters. The
presence of this gas should be detectable with future deep X-ray observations.


title: Raman spectroscopy of a single ion coupled to a high-finesse cavity

abstract:
  We describe an ion-based cavity-QED system in which the internal dynamics of
an atom is coupled to the modes of an optical cavity by vacuum-stimulated Raman
transitions. We observe Raman spectra for different excitation polarizations
and find quantitative agreement with theoretical simulations. Residual motion
of the ion introduces motional sidebands in the Raman spectrum and leads to ion
delocalization. The system offers prospects for cavity-assisted
resolved-sideband ground-state cooling and coherent manipulation of ions and
photons.


title: Measurements of Single-Top Quark Production at the Tevatron

abstract:
  The latest measurements of the cross sections for singly-produced top quarks
at the Fermilab Tevatron are presented. The small expected signals and the
large, uncertain backgrounds require careful event selection, sophisticated
methods for separating signal events from background events, and data-based
background predictions and fits. Both the CDF and D0 collaborations have solid
evidence of single top production, using 2.7 fb-1 and 0.9 fb-1 of data,
respectively. Both collaborations perform several analyses to measure the total
single-top cross section sigma_s + sigma_t, as well as sigma_s and sigma_t
separately.


title:
The Correlation of Star Formation Quenching with Internal Galaxy
  Properties and Environment

abstract:
  We investigate the correlation of star formation quenching with internal
galaxy properties and large scale environment (halo mass) in empirical data and
theoretical models. We make use of the halo-based Group Catalog of Yang and
collaborators, which is based on the Sloan Digital Sky Survey. Data from the
Galaxy Evolution Explorer (GALEX) are also used to extract the recent star
formation rate. In order to investigate the environmental effects, we examine
the properties of "central" and "satellite" galaxies separately. For central
galaxies, we are unable to conclude whether star formation quenching is
primarily connected with halo mass or stellar mass, because these two
quantities are themselves strongly correlated. For satellite galaxies, a nearly
equally strong dependence on halo mass and stellar mass is seen. We make the
same comparison for five different semi-analytic models based on three
independently developed codes. We find that the models with AGN feedback
reproduce reasonably well the dependence of the fraction of central red and
passive galaxies on halo mass and stellar mass. However, for satellite
galaxies, the same models badly overproduce the fraction of red/passive
galaxies and do not reproduce the empirical trends with stellar mass or halo
mass. This {\em satellite overquenching problem} is caused by the too-rapid
stripping of the satellites' hot gas halos, which leads to rapid strangulation
of star formation.


title:
The population of early-type galaxies at 1<z<2 - New clues on their
  formation and evolution

abstract:
  [Abridged]We present the morphological analysis based on HST-NICMOS
observations in the F160W filter of a sample of 32 early-type galaxies (ETGs)
at 1<z<2 with spectroscopic confirmation of their redshift and spectral type.
We find that ETGs at are composed of two distinct populations, an older
population (oETGs) and a younger population (yETGs) whose mean ages differ by
about 1.5-2 Gyr. Young ETGs are not denser than local ones since they follow
the size-mass relation of local ETGs and luminosity evolution brings them onto
the local Kormendy and size-luminosity relations. On the constrary, old ETGs do
not follow the size-mass relation of local ETGs and luminosity evolution does
not account for the discrepancy they show with respect to the local
size-luminosity and Kormendy relations. An increase of their effective radius
R_e by a factor 2.5-3 (a density decrease by a factor 15-30) from z~1.5-2 to
z~0 is required to bring these galaxies onto the local scaling relations. The
different behaviour shown by the two populations implies different formation
and evolution scenarios. The older population must have formed at higher-z in a
sort of dissipative gas-rich collapse ables to produce remnants which at z~2
are old and compact. The size evolution they must experience from z~2 to z~0
has to leave unchanged their mass to not exceed the local number of high-mass
ETGs. Thus, major merging cannot fit this requirement. The younger population
of ETGs can be formed later through subsequent episodes of merging which
increased progressively their size and assembled their mass down to z~2. At z<2
they evolve purely in luminosity since episodes of major merging would bring
them far from the local scaling relations.


title:
Molecules in G1.6-0.025 - 'Hot' Chemistry in the Absence of Star
  Formation at the Periphery of the Galactic Center Region

abstract:
  We present molecular line mapping of the Giant Molecular Cloud G1.6-0.025,
which is located at the high longitude end of the Central Molecular Zone of our
Galaxy. We assess the degree of star formation activity in that region using
several tracers and find very little. We made a large scale, medium (2')
resolution map in the J = 2-1 transition of SiO for which we find clumpy
emission over a ~0.8 x 0.3 degree-sized region stretching along the Galactic
plane. Toward selected positions we also took spectra in the easy to excite
J_k=2_k-1_k quartet of CH3OH and the CS 2-1 line. Throughout the cloud these
\meth lines are, remarkably, several times stronger than, both, the CS and the
SiO lines. The large widths of all the observed lines, similar to values
generally found in the Galactic center, indicate a high degree of turbulence.
Several high LSR velocity clumps that have 0-80 km/s higher velocities than the
bulk of the molecular cloud appear at the same projected position as "normal"
velocity material; this may indicate cloud-cloud collisions. Statistical
equilibrium modeling of the CH3OH lines observed by us and others yield
relatively high densities and moderate temperatures for a representative dual
velocity position. We find 8 10^4 cm-3/30 K for material in the G1.6-0.025
cloud and a higher temperature (190 K), but a 50% lower density in a high
velocity clump projected on the same location. Several scenarios are discussed
in which shock chemistry might enhance the CH3OH and SiO abundances in
G1.6-0.025 and elsewhere in the Central Molecular Zone.


title: Solar-like oscillations in red giants in the CoRoT exo-field

abstract:
  Asteroseismic observations from space can provide us with long time series of
uninterrupted high quality data for many stars at the same time. The CoRoT
satellite (Convection Rotation and planetary Transits) was launched
successfully in December 2006 and provides high precision photometery for a
large number of stars. Here we present our research on (late G and K) red giant
stars observed during the first long run (150 days) of CoRoT with the 'eye'
dedicated to exo-planet research.


title: On the nucleation of hadronic domains in the quark-hadron transition

abstract:
  We present numerical results on bubble profiles, nucleation rates and time
evolution for a weakly first-order quark-hadron phase transition in different
expansion scenarios. We confirm the standard picture of a cosmological
first-order phase transition, in which the phase transition is entirely
dominated by nucleation. We also show that, even for expansion rates much lower
than those expected in heavy-ion collisions nucleation is very unlikely,
indicating that the main phase conversion mechanism is spinodal decomposition.


title: Toric moment mappings and Riemannian structures

abstract:
  Coadjoint orbits for the group SO(6) parametrize Riemannian G-reductions in
six dimensions, and we use this correspondence to interpret symplectic
fibrations between these orbits, and to analyse moment polytopes associated to
the standard Hamiltonian torus action on the coadjoint orbits. The theory is
then applied to describe so-called intrinsic torsion varieties of Riemannian
structures on the Iwasawa manifold.


title: Merger Induced Globular Cluster Formation and Galaxy Evolution

abstract:
  Based on the earlier work of Gunn and McCrea we model the formation of
globular clusters in merging galaxies. Neutral hydrogen observations of dwarf
irregular galaxies as well as more luminous systems are used to provide the key
parameters of the model. The observations indicate that clusters with the mass
of globular clusters should still be forming today. The model is incorporated
into a phenomenological picture of galaxy evolution making use of a simple
chemical evolution model. These results are compared to recent observations of
the metallicity distributions of F and G stars from a recent large SDSS survey.
The comparisons are consistent with an anisotropic collapse and merging of a
large number of dwarf irregular galaxies for the formation of the Galaxy.


title: Reconstruction of the second layer of Ag on Pt(111)

abstract:
  The reconstruction of an Ag monolayer on Ag/Pt(111) is analyzed
theoretically, employing a vertically extended Frenkel-Kontorova model whose
parameters are derived from density functional theory. Energy minimization is
carried out using simulated quantum annealing techniques. Our results are
compatible with the STM experiments, where a striped pattern is initially found
which transforms into a triangular reconstruction upon annealing. In our model
we recognize the first structure as a metastable state, while the second one is
the true energy minimum.


title:
Pathways to massive black holes and compact star clusters in
  pre-galactic dark matter haloes with virial temperatures > 10000K

abstract:
  Large dynamic range numerical simulations of atomic cooling driven collapse
of gas in pre-galactic DM haloes with T_vir ~ 10000 K show that the gas loses
90% and more of its angular momentum before rotational support sets in. In a
fraction of these haloes where the metallicity is low and UV radiation
suppresses H_2 cooling, conditions are thus very favourable for the rapid
build-up of massive black holes. Depending on the progression of metal
enrichment, the continued suppression of H_2 cooling by external and internal
UV radiation and the ability to trap the entropy produced by the release of
gravitational energy, the gas at the centre of the halo is expected to form a
supermassive star, a stellar-mass black hole accreting at super-Eddington
accretion rates or a compact star-cluster undergoing collisional run-away of
massive stars at its centre. In all three cases a massive black hole of
initially modest mass finds itself at the center of a rapid inflow of gas with
inflow rates of ~ 1 M_solar\yr. The massive black hole will thus grow quickly
to a mass of 10^5 to 10^6 M_solar until further inflow is halted either by
consumption of gas by star formation or by the increasing energy and momentum
feedback from the growing massive black hole. Conditions for the formation of
massive seed black holes in this way are most favourable in haloes with T_vir ~
15000 K and V_vir ~ 20 km\s with less massive haloes not allowing collapse of
gas by atomic cooling and more massive haloes being more prone to
fragmentation. This should imprint a characteristic mass on the mass spectrum
of an early population of massive black hole seeds in pre-galactic haloes which
will later grow into the observed population of supermassive black holes in
galactic bulges.


title:
Measuring Dust Production in the Small Magellanic Cloud Core-Collapse
  Supernova Remnant 1E 0102.2-7219

abstract:
  We present mid-infrared spectral mapping observations of the core-collapse
supernova remnant 1E 0102.2-7219 in the Small Magellanic Cloud using the
InfraRed Spectrograph (IRS) on the Spitzer Space Telescope. The remnant shows
emission from fine structure transitions of neon and oxygen as well as
continuum emission from dust. Comparison of the mid-IR dust emission with
observations at x-ray, radio and optical wavelengths shows that the dust is
associated with the supernova ejecta and is thus newly formed in the remnant.
The spectrum of the newly formed dust is well reproduced by a model that
includes 3x10^-3 solar masses of amorphous carbon dust at 70 K and 2x10^-5
solar masses of Mg2SiO4 (forsterite) at 145 K. Our observations place a lower
limit on the amount of dust in the remnant since we are not sensitive to the
cold dust in the unshocked ejecta. We compare our results to observations of
other core-collapse supernovae and remnants, particularly Cas A where very
similar spectral mapping observations have been carried out. We observe a a
factor of ~10 less dust in E 0102 than seen in Cas A, although the amounts of
amorphous carbon and forsterite are comparable.


title: Parton dynamics and hadronization from the sQGP

abstract:
  The hadronization of an expanding partonic fireball is studied within the
Parton-Hadron-Strings Dynamics (PHSD) approach which is based on a dynamical
quasiparticle model (DQPM) matched to reproduce lattice QCD results in
thermodynamic equilibrium. Apart from strong parton interactions the expansion
and development of collective flow is found to be driven by strong gradients in
the parton mean-fields. An analysis of the elliptic flow $v_2$ demonstrates a
linear correlation with the spatial eccentricity $\epsilon$ as in case of ideal
hydrodynamics. The hadronization occurs by quark-antiquark fusion or 3 quark/3
antiquark recombination which is described by covariant transition rates. Since
the dynamical quarks become very massive, the formed resonant 'pre-hadronic'
color-dipole states ($q\bar{q}$ or $qqq$) are of high invariant mass, too, and
sequentially decay to the groundstate meson and baryon octets increasing the
total entropy. This solves the entropy problem in hadronization in a natural
way. Hadronic particle ratios turn out to be in line with those from a
grandcanonical partition function at temperature $T \approx 170$ MeV.


title: Nonabelian plasma instabilities in Bjorken expansion

abstract:
  Plasma instabilities are parametrically the dominant nonequilibrium dynamics
of a weakly coupled quark-gluon plasma. In recent years the time evolution of
the corresponding collective colour fields has been studied in stationary
anisotropic situations. Here I report on recent numerical results on the time
evolution of the most unstable modes in a longitudinally expanding plasma as
they grow from small rapidity fluctuations to amplitudes where non-Abelian
self-interactions become important.


title: Multicomponent systems in the new quantum statistical approach

abstract:
  The paper is devoted to further development of the new approach in
equilibrium statistical mechanics the basis of which was worked out in a series
of articles by the author. The approach proceeds on the use of a hierarchy of
equations for reduced density matrices in the case of thermodynamic
equilibrium. The present paper deals with a system containing particles of
several kinds with arbitrary spin, for which the hierarchy obtained previously
for a single-component system is generalized. Thermodynamics of the
multicomponent system described by the hierarchy deduced is constructed as
well.


title: A theory of jet shapes and cross sections: from hadrons to nuclei

abstract:
  For jets, with great power comes great opportunity. The unprecedented center
of mass energies available at the LHC open new windows on the QGP: we
demonstrate that jet shape and jet cross section measurements become feasible
as a new, differential and accurate test of the underlying QCD theory. We
present a first step in understanding these shapes and cross sections in heavy
ion reactions. Our approach allows for detailed simulations of the experimental
acceptance/cuts that help isolate jets in such high-multiplicity environment.
It is demonstrated for the first time that the pattern of stimulated gluon
emission can be correlated with a variable quenching of the jet rates and
provide an approximately model-independent approach to determining the
characteristics of the medium-induced bremsstrahlung spectrum. Surprisingly, in
realistic simulations of parton propagation through the QGP we find a minimal
increase in the mean jet radius even for large jet attenuation. Jet broadening
is manifest in the tails of the energy distribution away from the jet axis and
its quantification requires high statistics measurements that will be possible
at the LHC.


title:
Dynamical instabilities of dissipative solitons in nonlinear optical
  cavities with nonlocal materials

abstract:
  In this work we characterize the dynamical instabilities of localized
structures exhibited by a recently introduced Gelens et al., Phys. Rev. A 75,
063812 2007 generalization of the Lugiato-Lefever model that includes a weakly
nonlocal response of an intracavity metamaterial. A rich scenario, in which the
localized structures exhibit different types of oscillatory instabilities,
tristability, and excitability, including a regime of conditional excitability
in which the system is bistable, is presented and discussed. Finally, it is
shown that the scenario is organized by a pair of Takens-Bogdanov codimension-2
points.


title: A note on tachyon actions in string theory

abstract:
  A number of spacetime fields in string theory (notably the metric, dilaton,
bosonic and type 0 bulk closed-string tachyon, and bosonic open-string tachyon)
have the following property: whenever the spacetime field configuration
factorizes in an appropriate sense, the matter sector of the world-sheet theory
factorizes into a tensor product of two decoupled theories. Since the beta
functions for such a product theory necessarily also factorize, this property
strongly constrains the form of the spacetime action encoding those beta
functions. We show that this constraint alone--without needing actually to
compute any of the beta functions--is sufficient to fix the form of the
two-derivative action for the metric-dilaton system, as well as the potential
for the bosonic open-string tachyon. We also show that no action consistent
with this constraint exists for the closed-string tachyon coupled to the metric
and dilaton.


title:
Maps on Divisor Class Groups Induced by Ring Homomorphisms of Finite
  Flat Dimension

abstract:
  Let f: A\to B be a ring homomorphism between Noetherian normal integral
domains. We establish a general criterion for f to induce a homomorphism Cl(f):
Cl(A)\to Cl(B) on divisor class groups. For instance, this criterion applies
whenever f has finite flat dimension; this special case generalizes the more
classical situations where f is flat or is surjective with kernel generated by
an A-regular element. We extend some of Spiroff's work on the kernels of
induced maps to this more general setting.


title: Lessons Learned from Sloan Digital Sky Survey Operations

abstract:
  Astronomy is changing. Large projects, large collaborations, and large
budgets are becoming the norm. The Sloan Digital Sky Survey (SDSS) is one
example of this new astronomy, and in operating the original survey, we put in
place and learned many valuable operating principles. Scientists sometimes have
the tendency to invent everything themselves but when budgets are large,
deadlines are many, and both are tight, learning from others and applying it
appropriately can make the difference between success and failure. We offer
here our experiences well as our thoughts, opinions, and beliefs on what we
learned in operating the SDSS.


title: Intrinsic flavor violation for massive neutrinos

abstract:
  It is shown that intrinsic neutrino flavor violation invariably occurs when
neutrinos are created within the SM augmented by the known massive neutrinos,
with mixing and nondegenerate masses. The effects are very small but much
greater than the naive estimate $\Delta m^2/E_\nu^2$ or the branching ratio of
indirect flavor violating processes such as $\mu\to e\gamma$ within the SM. We
specifically calculate the probability (branching ratio) of pion decay
processes with flavor violation, such as $\pi\to \mu\bar{\nu}_e$, showing
nonzero results.


title: Limit Theorems for Individual-Based Models in Economics and Finance

abstract:
  There is a widespread recent interest in using ideas from statistical physics
to model certain types of problems in economics and finance. The main idea is
to derive the macroscopic behavior of the market from the random local
interactions between agents. Our purpose is to present a general framework that
encompasses a broad range of models, by proving a law of large numbers and a
central limit theorem for certain interacting particle systems with very
general state spaces. To do this we draw inspiration from some work done in
mathematical ecology and mathematical physics. The first result is proved for
the system seen as a measure-valued process, while to prove the second one we
will need to introduce a chain of embeddings of some abstract Banach and
Hilbert spaces of test functions and prove that the fluctuations converge to
the solution of a certain generalized Gaussian stochastic differential equation
taking values in the dual of one of these spaces.


title:
Enhancement of the superconducting transition temperature in cuprate
  heterostructures

abstract:
  Is it possible to increase Tc by constructing cuprate heterostructures, which
combine the high pairing energy of underdoped layers with the large carrier
density of proximate overdoped layers? We investigate this question within a
model bilayer system using an effective theory of the doped Mott insulator.
Interestingly, the question hinges on the fundamental nature of the
superconducting state in the underdoped regime. Within a plain slave boson mean
field theory, there is absolutely no enhancement of Tc. However, we do get a
substantial enhancement for moderate inter-layer tunneling when we use an
effective low energy theory of the bilayer in which the effective quasiparticle
charge in the underdoped regime is taken as an independent phenomenological
parameter. We study the Tc enhancement as a function of the doping level and
the inter-layer tunneling, and discuss possible connections to recent
experiments by Yuli et al. [Phys. Rev. Lett. 101, 057005 (2008)]. Finally, we
predict a unique paramagnetic reduction of the zero temperature phase stiffness
of coupled layers, which depends on the difference in the current carried by
quasiparticles on the two types of layers as (J1-J2)^2.


title:
Nonmodal amplification of stochastic disturbances in strongly elastic
  channel flows

abstract:
  Nonmodal amplification of stochastic disturbances in elasticity-dominated
channel flows of Oldroyd-B fluids is analyzed in this work. For
streamwise-constant flows with high elasticity numbers $\mu$ and finite
Weissenberg numbers $We$, we show that the linearized dynamics can be
decomposed into slow and fast subsystems, and establish analytically that the
steady-state variances of velocity and polymer stress fluctuations scale as $O
(We^2)$ and $O (We^4)$, respectively. This demonstrates that large velocity
variance can be sustained even in weakly inertial stochastically driven channel
flows of viscoelastic fluids. We further show that the wall-normal and spanwise
forces have the strongest impact on the flow fluctuations, and that the
influence of these forces is largest on the fluctuations in streamwise velocity
and the streamwise component of the polymer stress tensor. The underlying
physical mechanism involves polymer stretching that introduces a lift-up of
flow fluctuations similar to vortex tilting in inertia-dominated flows. The
validity of our analytical results is confirmed in stochastic simulations. The
phenomenon examined here provides a possible route for the early stages of a
bypass transition to elastic turbulence and might be exploited to enhance
mixing in microfluidic devices.


title:
Phonon softening and anomalous mode near the $x_{c}=0.5$ quantum
  critical point in Ca$_{2-x}$Sr$_{x}$RuO$_4$

abstract:
  Inelastic neutron scattering is used to measure the temperature dependent
phonon dispersion in Ca$_{2-x}$Sr$_{x}$RuO$_{4}$ ($x=0.4$, 0.6). The in-plane
$\Sigma_{4}$ octahedral tilt mode softens significantly at the zone boundary of
the high temperature tetragonal (HTT) \textit{I4}$_{\mathit{1}}$\textit{/acd}
structure as the temperature approaches the transition to a low temperature
orthorhombic (LTO) \textit{Pbca} phase. This behavior is similar to that in
La$_2$CuO$_4$, but a new inelastic feature that is not found in the cuprate is
present. An anomalous phonon mode is observed at energy transfers greater than
the $\Sigma_{4}$ albeit with similar dispersion. This anomalous phonon mode
never softens below $\sim 5$ meV, even for temperatures below the HTT-LTO
transition. This mode is attributed to the presence of intrinsic structural
disorder within the \textit{I4}$_{\mathit{1}}$\textit{/acd} tetragonal
structure of the doped ruthenate.


title:
Classical solutions for the Lorentz-violating and CPT-even term of the
  Standard Model Extension

abstract:
  In this work, we calculate the classical solutions for the electrodynamics
stemming from the Lorentz-violating (LV) and CPT-even term of the Standard
Model Extension. The solutions for point-like and extended charges are obtained
from the wave equations by means of the Green method. A dipolar expansion is
written for the field strengths. It is explicitly shown that charge and current
generate first order effects for the magnetic and electric fields,
respectively. Using the magnetic field generated by a macroscopic 1C charged
sphere, we establish a stringent bound for the LV parameter:$\kappa \leq
10^{-16}.$


title:
Small probability events for two-layer geophysical flows under
  uncertainty

abstract:
  The stochastics two-layer quasi-geostrophic flow model is an intermediate
system between the single-layer two dimensional barotropic flow model and the
continuously stratified three dimensional baroclinic flow model. This model is
widely used to investigate basic mechanisms in geophysical flows, such as
baroclinic effects, the Gulf Stream and subtropical gyres.
  A large deviation principle for the two-layer quasi-geostrophic flow model
under uncertainty is proved. The proof is based on the Laplace principle and a
variational approach. This approach does not require the exponential tightness
estimates which are needed in other methods for establishing large deviation
principles.


title: Naturality of Rieffel's Morita equivalence for proper actions

abstract:
  Suppose that a locally compact group $G$ acts freely and properly on the
right of a locally compact space $T$. Rieffel proved that if $\alpha$ is an
action of $G$ on a $C^*$-algebra $A$ and there is an equivariant embedding of
$C_0(T)$ in $M(A)$, then the action $\alpha$ of $G$ on $A$ is proper, and the
crossed product $A\rtimes_{\alpha,r}G$ is Morita equivalent to a generalised
fixed-point algebra $\Fix(A,\alpha)$ in $M(A)^\alpha$. We show that the
assignment $(A,\alpha)\mapsto\Fix(A,\alpha)$ extends to a functor $\Fix$ on a
category of $C^*$-dynamical systems in which the isomorphisms are Morita
equivalences, and that Rieffel's Morita equivalence implements a natural
isomorphism between a crossed-product functor and $\Fix$. From this, we deduce
naturality of Mansfield imprimitivity for crossed products by coactions,
improving results of Echterhoff-Kaliszewski-Quigg-Raeburn and Kaliszewski-Quigg
Raeburn, and naturality of a Morita equivalence for graph algebras due to
Kumjian and Pask.


title: Self-sustained nonlinear waves in traffic flow

abstract:
  In analogy to gas-dynamical detonation waves, which consist of a shock with
an attached exothermic reaction zone, we consider herein nonlinear traveling
wave solutions, termed "jamitons," to the hyperbolic ("inviscid") continuum
traffic equations. Generic existence criteria are examined in the context of
the Lax entropy conditions. Our analysis naturally precludes traveling wave
solutions for which the shocks travel downstream more rapidly than individual
vehicles. Consistent with recent experimental observations from a periodic
roadway (Sugiyama et al., New Journal of Physics, 10, 2008), our numerical
calculations show that, under appropriate road conditions, jamitons are
attracting solutions, with the time evolution of the system converging towards
a jamiton-dominated configuration. Jamitons are characterized by a sharp
increase in density over a relatively compact section of the roadway.
Applications of our analysis to traffic modeling and control are examined by
way of a detailed example.

categories: physics.soc-ph math.AP nlin.PS physics.flu-dyn


title:
Concentration Inequalities and Laws of Large Numbers under Epistemic
  Irrelevance

abstract:
  This paper presents concentration inequalities and laws of large numbers
under weak assumptions of irrelevance, expressed through lower and upper
expectations. The results are variants and extensions of De Cooman and
Miranda's recent inequalities and laws of large numbers. The proofs indicate
connections between concepts of irrelevance for lower/upper expectations and
the standard theory of martingales.


title:
Empirical Constraints on Parton Energy Loss in Nucleus-Nucleus
  Collisions at RHIC

abstract:
  We present empirical features of parton energy loss in nucleus-nucleus
collisions at RHIC through studies of the spectra and nuclear modification
factors ($R_{AA}$) for charged hadrons, neutral pions ($\pi^0$) and
non-photonic electrons. The flat distribution of $R_{AA}$ at high transverse
momentum ($p_{T}$) for a given collision centrality is consistent with a
scenario where parton energy loss $\Delta p_{T}$ is proportional to $p_{T}$.
The centrality dependence of the parton energy loss indicates the absence of
path length dependence in the magnitude of energy loss. The lack of strong path
length dependence suggests a dynamical picture where the dense partonic medium
undergoes rapid expansion and the density of the medium falls rapidly in the
first a few Fermi interval, which may be much shorter than the full path
length. Implications of the empirical constraints on the parton energy loss
will also be discussed.


title:
Intrinsic Localized Modes Observed in the High Temperature Vibrational
  Spectrum of NaI

abstract:
  Inelastic neutron measurements of the high-temperature lattice excitations in
NaI show that in thermal equilibrium at 555 K an intrinsic mode, localized in
three dimensions, occurs at a single frequency near the center of the spectral
phonon gap, polarized along [111]. At higher temperatures the intrinsic
localized mode gains intensity. Higher energy inelastic neutron and x-ray
scattering measurements on a room-temperature NaI crystal indicate that the
creation energy of the ground state of the intrinsic localized mode is 299 meV.


title:
Standard random walks and trapping on the Koch network with scale-free
  behavior and small-world effect

abstract:
  A vast variety of real-life networks display the ubiquitous presence of
scale-free phenomenon and small-world effect, both of which play a significant
role in the dynamical processes running on networks. Although various dynamical
processes have been investigated in scale-free small-world networks, analytical
research about random walks on such networks is much less. In this paper, we
will study analytically the scaling of the mean first-passage time (MFPT) for
random walks on scale-free small-world networks. To this end, we first map the
classical Koch fractal to a network, called Koch network. According to this
proposed mapping, we present an iterative algorithm for generating the Koch
network, based on which we derive closed-form expressions for the relevant
topological features, such as degree distribution, clustering coefficient,
average path length, and degree correlations. The obtained solutions show that
the Koch network exhibits scale-free behavior and small-world effect. Then, we
investigate the standard random walks and trapping issue on the Koch network.
Through the recurrence relations derived from the structure of the Koch
network, we obtain the exact scaling for the MFPT. We show that in the infinite
network order limit, the MFPT grows linearly with the number of all nodes in
the network. The obtained analytical results are corroborated by direct
extensive numerical calculations. In addition, we also determine the scaling
efficiency exponents characterizing random walks on the Koch network.


title:
Multi-Scale CLEAN: A comparison of its performance against classical
  CLEAN in galaxies using THINGS

abstract:
  A practical evaluation of the Multi-Scale CLEAN algorithm is presented. The
data used in the comparisons are taken from The HI Nearby Galaxy Survey
(THINGS). The implementation of Multi-Scale CLEAN in the CASA software package
is used, although comparisons are made against the very similar
Multi-Resolution CLEAN algorithm implemented in AIPS. Both are compared against
the classical CLEAN algorithm (as implemented in AIPS). The results of this
comparison show that several of the well-known characteristics and issues of
using classical CLEAN are significantly lessened (or eliminated completely)
when using the Multi-Scale CLEAN algorithm. Importantly, Multi-Scale CLEAN
reduces significantly the effects of the clean `bowl' caused by missing
short-spacings, and the `pedestal' of low-level un-cleaned flux (which affects
flux scales and resolution). Multi-Scale CLEAN can clean down to the noise
level without the divergence suffered by classical CLEAN. We discuss practical
applications of the added contrast provided by Multi-Scale CLEAN using two
selected astronomical examples: HI holes in the interstellar medium and
anomalous gas structures outside the main galactic disk.


title:
The relation between stellar mass and weak lensing signal around
  galaxies: Implications for MOND

abstract:
  We study the amplitude of the weak gravitational lensing signal as a function
of stellar mass around a sample of relatively isolated galaxies. This selection
of lenses simplifies the interpretation of the observations, which consist of
data from the Red- sequence Cluster Survey and the Sloan Digital Sky Survey. We
find that the amplitude of the lensing signal as a function of stellar mass is
well described by a power law with a best fit slope \alpha= 0.74 \pm 0.08. This
result is inconsistent with Modified Newtonian Dynamics, which predicts \alpha
= 0.5 (we find \alpha > 0.5 with 99.7% confidence). As a related test, we
determine the MOND mass-to-light ratio as a function of luminosity. Our results
require dark matter for the most luminous galaxies (L >=10^11 L_sun). We rule
out an extended halo of gas or active neutrinos as a way of reconciling our
findings with MOND. Although we focus on a single alternative gravity model, we
note that our results provide an important test for any alternative theory of
gravity.


title: Influence of Dark Matter on Light Propagation in Solar System

abstract:
  We investigated the influence of dark matter on light propagation in the
solar system. We assumed the spherical symmetry of spacetime and derived the
approximate solution of the Einstein equation, which consists of the
gravitational attractions caused by the central celestial body, i.e. the Sun,
and the dark matter surrounding it. We expressed the dark matter density in the
solar system in the following simple power-law form, $\varrho(t, r) =
\rho(t)(\ell/r)^k$, where $t$ is the coordinate time; $r$, the radius from the
central body; $\ell$, the normalizing factor; $k$, the exponent characterizing
$r$-dependence of dark matter density; and $\rho(t)$, the arbitrary function of
time $t$. On the basis of the derived approximate solution, we focused on light
propagation and obtained the additional corrections of the gravitational time
delay and the relative frequency shift caused by the dark matter. As an
application of our results, we considered the secular increase in the
astronomical unit reported by Krasinsky and Brumberg (2004) and found that it
was difficult to provide an explanation for the observed $d{\rm AU}/dt = 15 \pm
4 ~[{\rm m/century}]$.


title:
Spectral Effects of Fast Response Cross Kerr Non-Linearity on Quantum
  Gate

abstract:
  According to idealized models, a strong Kerr non-linearity may be used to
build optical quantum gates for optical quantum information processing by
inducing conditional phase shifts on quantum states. Recently, Shapiro (PRA 73,
062305 (2006)) argued that for a Kerr medium with non-instantaneous but fast
response, essentially no phase shift is induced on two-single-photon input
states, and thus a quantum gate build from such a medium cannot work. Here we
show that a fast response Kerr medium induces some but very little phase shifts
on a two-single-photon input state, and it is insufficient for high fidelity
quantum computation. We point out that this is caused by the medium imparting
spectral entanglement to the input photons. We further show that a way to
circumvent this problem and achieve a high fidelity gate, is to engineer the
dispersion properties of the medium to give a dominant spectral effect over the
non-instantaneous response, in addition to satisfying a phase matching
condition.


title: Blume-Emery-Griffiths dynamics in social networks

abstract:
  We introduce the Blume-Emery-Griffiths (BEG) model in a social networks to
describe the three-state dynamics of opinion formation. It shows that the
probability distribution function of the time series of opinion is a
Gaussian-like distribution. We also study the response of BEG model to the
external periodic perturbation. One can observe that both the interior
thermo-noise and the external field result in phase transition, which is a
split phenomena of the opinion distributions. It is opposite between the effect
acted on the opinion systems of the amplitude of the external field and of the
thermo-noise.


title:
Classes of permutation polynomials based on cyclotomy and an additive
  analogue

abstract:
  I present a construction of permutation polynomials based on cyclotomy, an
additive analogue of this construction, and a generalization of this additive
analogue which appears to have no multiplicative analogue. These constructions
generalize recent results of J. Marcos from arXiv:0810.2738v1.


title: Non-Gaussian Correlations Outside the Horizon II: The General Case

abstract:
  The results of a recent paper [0808.2909] are generalized. A more detailed
proof is presented that under essentially all conditions, the non-linear
classical equations governing matter and gravitation in cosmology have
``adiabatic'' solutions in which, far outside the horizon, in a suitable gauge,
the reduced spatial metric $g_{ij}({\bf x},t)/a^2(t)$ becomes a
time-independent function ${\cal G}_{ij}({\bf x})$, and all perturbations to
the other metric components and to all matter variables vanish. The corrections
are of order $a^{-2}$, and their ${\bf x}$-dependence is now explicitly given
in terms of ${\cal G}_{ij}({\bf x})$ and its derivatives. The previous results
for the time-dependence of the corrections to $g_{ij}({\bf x},t)/a^2(t)$ in the
case of multi-scalar field theories are now shown to apply for any theory whose
anisotropic inertia vanishes to order $a^{-2}$. Further, it is shown that the
adiabatic solutions are attractive as $a$ becomes large for the case of single
field inflation and now also for thermal equilibrium with no non-zero conserved
quantities, and the $O(a^{-2})$ corrections to the other dynamical variables
are explicitly calculated in both cases.


title: Quantum dynamics of the O + OH -> H + O2 reaction at low temperatures

abstract:
  We report quantum dynamics calculations of the O + OH -> H + O2 reaction on
two different representations of the electronic ground state potential energy
surface (PES) using a time-independent quantum formalism based on
hyperspherical coordinates. Calculations show that several excited vibrational
levels of the product O2 molecule are populated in the reaction. Rate
coefficients evaluated using both PESs were found to be very sensitive to the
energy resolution of the reaction probability, especially at temperatures lower
than 100 K. It is found that the rate coefficient remains largely constant in
the temperature range 10-39 K, in agreement with the conclusions of a recent
experimental study [Carty et al., J. Phys. Chem. A 110, 3101 (2006)]. This is
in contrast with the time-independent quantum calculations of Xu et al. [J.
Chem. Phys. 127, 024304 (2007)] which, using the same PES, predicted two orders
of magnitude drop in the rate coefficient value from 39 K to 10 K. Implications
of our findings to oxygen chemistry in the interstellar medium are discussed.


title: The background field method on the lattice

abstract:
  The background field method has been used successfully to determine hadron
electromagnetic polarizabilities. Recently questions have been raised regarding
the proper way to deal with the electric field on the lattice. In this paper,
we show how the presence of a background electric field affects the quark
hopping matrix. We use this formulation to carry out simulations on quenched
configurations, and we present the results for neutron electric polarizability
for pion masses as low as $500\MeV$. We find that the polarizability is roughly
constant for the quark masses considered, $\alpha\sim 1.5 \times 10^{-4}
\fm^3$. While the polarizability is positive, it is significantly smaller than
the experimental value due to the fact that the quark masses used are too
large.


title: On a theorem of Carlitz

abstract:
  Carlitz proved that, for any prime power q other than 2, the group of all
permutations of the finite field F_q is generated by the permutations induced
by degree-one polynomials and x^{q-2}. His proof relies on a remarkable
polynomial which appears to have been found by magic. We show here that no
magic is required: there is a straightforward way to produce a simple
polynomial which has the same remarkable properties as the complicated
polynomial in Carlitz's proof. We also identify the crucial subtlety which
allows such simple polynomials to exist, and discuss some consequences.


title:
Epitaxial ferromagnetic Fe$_{3}$Si/Si(111) structures with high-quality
  hetero-interfaces

abstract:
  To develop silicon-based spintronic devices, we have explored high-quality
ferromagnetic Fe$_{3}$Si/silicon (Si) structures. Using low-temperature
molecular beam epitaxy at 130 $^circ$C, we realize epitaxial growth of
ferromagnetic Fe$_{3}$Si layers on Si (111) with keeping an abrupt interface,
and the grown Fe$_{3}$Si layer has the ordered $DO_{3}$ phase. Measurements of
magnetic and electrical properties for the Fe$_{3}$Si/Si(111) yield a magnetic
moment of ~ 3.16 $mu_{B}$/f.u. at room temperature and a rectifying
Schottky-diode behavior with the ideality factor of ~ 1.08, respectively.


abstract:
  Graphene has many unique properties that make it an ideal material for
fundamental studies as well as for potential applications. Here we review the
recent results on the Raman spectroscopy and imaging of graphene. Raman
spectroscopy and imaging can be used as a quick and unambiguous method to
determine the number of graphene layers. Following, the strong Raman signal of
single layer graphene compared to graphite is explained by an interference
enhancement model. We have also studied the effect of substrates, the top layer
deposition, the annealing process, as well as folding (stacking order) on the
physical and electronic properties of graphene. Finally, Raman spectroscopy of
epitaxial graphene grown on SiC substrate is presented and strong compressive
strain on epitaxial graphene is observed. The results presented here are
closely related to the application of graphene on nano-electronic device and
help on the better understanding of physical and electronic properties of
graphene.


title:
Adaptive Hybrid Deflection and Retransmission Routing for Optical
  Burst-Switched Networks

abstract:
  Burst contention is a well known challenging problem in Optical Burst
Switching (OBS) networks. Deflection routing is used to resolve contention.
Burst retransmission is used to reduce the Burst Loss Ratio (BLR) by
retransmitting dropped bursts. Previous works show that combining deflection
and retransmission outperforms both pure deflection and pure retransmission
approaches. This paper proposes a new Adaptive Hybrid Deflection and
Retransmission (AHDR) approach that dynamically combines deflection and
retransmission approaches based on network conditions such as BLR and link
utilization. Network Simulator 2 (ns-2) is used to simulate the proposed
approach on different network topologies. Simulation results show that the
proposed approach outperforms static approaches in terms of BLR and goodput.


title: Multi-setting Bell inequality for qudits

abstract:
  We propose a generalized Bell inequality for two three-dimensional systems
with three settings in each local measurement. It is shown that this inequality
is maximally violated if local measurements are configured to be mutually
unbiased and a composite state is maximally entangled. This feature is similar
to Clauser-Horne-Shimony-Holt inequality for two qubits but is in contrast with
the two types of inequalities, Collins-Gisin-Linden-Massar-Popescu and
Son-Lee-Kim, for high-dimensional systems. The generalization to aribitrary
prime-dimensional systems is discussed.


title: Symplectic spreads and permutation polynomials

abstract:
  Every symplectic spread of PG(3,q), or equivalently every ovoid of Q(4,q), is
shown to give rise to a certain family of permutation polynomials of GF(q) and
conversely. This leads to an algebraic proof of the existence of the
Tits-Luneburg spread of W(2^{2h+1}) and the Ree-Tits spread of W(3^{2h+1}), as
well as to a new family of low-degree permutation polynomials over
GF(3^{2h+1}). We prove the permutation property of the latter polynomials via
an odd characteristic analogue of Dobbertin's approach to uniformly
representable permutation polynomials over GF(2^n). These new permutation
polynomials were later used by Ding, Wang, and Xiang in arXiv:math/0609586 to
produce new skew Hadamard difference sets.


title: Algebraic Cycles of a Fixed Degree

abstract:
  In this paper, the homotopy groups of Chow variety $C_{p,d}(P^n)$ of
effective $p$-cycles of degree $d$ is proved to be stable in the sense that $p$
or $n$ increases. We also obtain a negative answer to a question by Lawson and
Michelsohn on homotopy groups for the space of degree two cycles.


title: Liquid behavior of hot QGP in the finite temperature field theory

abstract:
  In this paper, we compare the dispersion relations of hard thermal loop and
complete one loop. It is shown that in the dynamical screening regime, the
completely one-loop calculation presents a prominent threshold frequency, below
which no pure imaginary mode survives. This phenomenon is responsible for the
oscillatory static in-medium potential and ultimately results in a damping
oscillation of the radial distribution function. We consider this typical shape
is the footprint of liquid QGP.


title: Everywhere ramified towers of global function fields

abstract:
  We consider a tower of function fields F_0 < F_1 < ... over a finite field
such that every place of every F_i ramified in the tower and the sequence
genus(F_i)/[F_i:F_0] has a finite limit. We also construct a tower in which
every place ramifies and the sequence N_i/[F_i:F_0] has a positive limit, where
N_i is the number of degree-one places of F_i. These towers answer questions
posed by Stichtenoth.


title:
The calculation of the equation of state of QCD at finite chemical
  potential and zero temperature

abstract:
  In this paper, we give a direct method for calculating the partition
function, and hence the equation of state (EOS) of Quantum Chromodynamics (QCD)
at finite chemical potential and zero temperature. In the EOS derived in this
paper the pressure density is the sum of two terms: the first term ${\cal
P}(\mu)|_{\mu=0}$ (the pressure density at $\mu=0$) is a $\mu$-independent
constant; the second term, which is totally determined by $G_R[\mu](p)$ (the
renormalized dressed quark propagator at finite $\mu$), contains all the
nontrivial $\mu$-dependence. By applying a general result in the rainbow-ladder
approximation of the Dyson-Schwinger approach obtained in our previous study
[Phys. Rev. {\bf C 71}, 015205 (2005)], $G_R[\mu](p)$ is calculated from the
meromorphic quark propagator proposed in [Phys. Rev. {\bf D 70}, 014014
(2004)]. From this the full analytic expression of the EOS of QCD at finite
$\mu$ and zero $T$ is obtained (apart from the constant term ${\cal
P}(\mu)|_{\mu=0}$ which can in principle be calculated from the CJT effective
action). A comparison between our EOS and the cold, perturbative EOS of QCD of
Fraga, Pisarski and Schaffner-Bielich is made. It is expected that our EOS can
provide a possible new approach for the study of neutron stars.


title:
Observations of the Goldreich-Kylafis effect in star-forming regions
  with XPOL at the IRAM 30m telescope

abstract:
  The Goldreich-Kylafis (GK) effect causes certain molecular line emission to
be weakly linearly polarized, e.g., in the presence of a magnetic field.
Compared to polarized dust emission, the GK effect has the potential to yield
additional information along the line of sight through its dependence on
velocity in the line profile. Our goal was to detect polarized molecular line
emission toward the DR21(OH), W3OH/H2O, G34.3+0.2, and UYSO1 dense molecular
cloud cores in transitions of rare CO isotopologues and CS. The feasibility of
such observations had to be established by studying the influence of polarized
sidelobes, e.g., in the presence of extended emission in the surroundings of
compact sources. The observations were carried out with the IRAM 30m telescope
employing the correlation polarimeter XPOL and using two orthogonally polarized
receivers. We produced beam maps to investigate instrumental polarization.
While in nearly all transitions toward all sources a polarized signal is found,
its degree of polarization only in one case surpasses the polarization that can
be expected due to instrumental effects. It is shown that any emission in the
polarized sidelobes of the system can produce instrumental polarization, even
if the source is unpolarized. Tentative evidence for astronomically polarized
line emission with pL<~1.5% was found in the CS(2-1) line toward G34.3+0.2.


title: Revisiting the Vector and Axial-vector Vacuum Susceptibilities

abstract:
  We re-investigate the vector and axial-vector vacuum susceptibilities by
taking advantage of the vector and axial-vector Ward-Takahashi identities. We
show analytically that, in the chiral limit, the vector vacuum susceptibility
is zero and the axial-vector vacuum susceptibility equals three fourths of the
square of the pion decay constant. Besides, our analysis reproduces the
Weinberg sum rule.


title:
Solving polynomial differential equations by transforming them to linear
  functional-differential equations

abstract:
  We present a new approach to solving polynomial ordinary differential
equations by transforming them to linear functional equations and then solving
the linear functional equations. We will focus most of our attention upon the
first-order Abel differential equation with two nonlinear terms in order to
demonstrate in as much detail as possible the computations necessary for a
complete solution. We mention in our section on further developments that the
basic transformation idea can be generalized to apply to differential equations
of any order, to a system of ordinary differential equations without first
differentially eliminating the multiple dependent variables, and even to
partial differential equations.


title: Spectral Theory of the Riemann Zeta-Function: Chapter 6: Appendix

abstract:
  The main aim of this article is to develop, in a fully detailed fashion, a
{\bf unified} theory of the spectral theory of mean values of individual
automorphic L-functions which is a natural extension of the fourth moment of
the Riemann zeta-function but does not admit any analogous argument and
requires a genuinely new method. Thus we first develop a relatively
self-contained account of the theory of automorphic representations, especially
highlighting the Kirillov model, with which we resolve the problem on the mean
value of those L-functions. As another reward, we gain a geometrical
understanding of sum formulas involving Kloosterman sums, which is in fact a
considerably simplified account of Cogdell-Piatetski-Shapiro's method. Our
reasoning is quite explicit in contrast to theirs.


title:
Microscopic calculation of the wobbling excitations by using the
  Woods-Saxon potential as a nuclear mean-field

abstract:
  The wobbling excitations of the triaxial superdeformed (TSD) bands in the Lu
and Hf region are studied by the microscopic framework of the cranked
mean-field and the random-phase approximation (RPA). In contrast to the
previous works, where the Nilsson potential was used, the more realistic
Woods-Saxon potential is employed as a nuclear mean-field. The wobbling-like
RPA solutions have been found systematically in the nuclei studied and their
characteristic properties are investigated in details. This confirms the
wobbling phonon excitations in TSD nuclei from the microscopic calculations.
The result of $B(E2)$ values indicates that the triaxial deformation is
increasing as a function of spin in the observed TSD bands in $^{163}$Lu.


title: Engel subalgebras of Leibniz algebras

abstract:
  Engel subalgebras of finite-dimensional Leibniz algebras are shown to have
similar properties to those of Lie algebras. Using these, it is shown that a
left Leibniz algebra, all of whose maximal subalgebras are right ideals, is
nilpotent. A primitive Leibniz algebra is shown to split over its minimal ideal
and that all the complements to its minimal ideal are conjugate. A subalgebra
is shown to be a Cartan subalgebra if and only if it is minimal Engel, provided
that the field has sufficiently many elements. Cartan subalgebras are shown to
have a property analogous to intravariance.


title:
Local expansion of photonic W state using a polarization dependent
  beamsplitter

abstract:
  We propose a simple probabilistic optical gate to expand polarization
entangled W states. The gate uses one polarization-dependent beamsplitter and a
horizontally polarized single photon as an ancilla. The gate post-selectively
expands $N$-photon W states to $(N+1)$-photon W states. A feasibility analysis
considering the realistic experimental conditions show that the scheme is
within the reach of the current quantum optical technologies.


title: Forbush decreases and turbulence levels at CME fronts

abstract:
  We seek to estimate the average level of MHD turbulence near coronal mass
ejection (CME) fronts as they propagate from the Sun to the Earth. We examine
the cosmic ray data from the GRAPES-3 tracking muon telescope at Ooty, together
with the data from other sources for three well observed Forbush decrease
events. Each of these events are associated with frontside halo Coronal Mass
Ejections (CMEs) and near-Earth magnetic clouds. In each case, we estimate the
magnitude of the Forbush decrease using a simple model for the diffusion of
high energy protons through the largely closed field lines enclosing the CME as
it expands and propagates from the Sun to the Earth. We use estimates of the
cross-field diffusion coefficient $D_{\perp}$ derived from published results of
extensive Monte Carlo simulations of cosmic rays propagating through turbulent
magnetic fields. Our method helps constrain the ratio of energy density in the
turbulent magnetic fields to that in the mean magnetic fields near the CME
fronts. This ratio is found to be $\sim$ 2% for the 11 April 2001 Forbush
decrease event, $\sim$ 6% for the 20 November 2003 Forbush decrease event and
$\sim$ 249% for the much more energetic event of 29 October 2003.


title: Quartet unconstrained formulation for massive higher spin fields

abstract:
  We generalize the unconstrained description of free massless higher spin
fields previously developed in [Nucl.Phys. B 779 (2007) 155] to the case of
free massive higher spin fields in a flat space of arbitrary dimension. The
Lagrangian is given in an easy-to-handle form for an arbitrary value of spin.
It is local, free from higher derivative terms, and involves a minimal number
of auxiliary fields needed for an unconstrained gauge invariant description of
a free massive higher spin field in arbitrary dimension.


title: Elliptic periods and primality proving

abstract:
  We define the ring of elliptic periods modulo an integer $n$ and give an
elliptic version of the AKS primality criterion.