title:
The Stellar Population And Origin Of The Mysterious High-Latitude Star
  Forming Cloud CG 12

abstract:
  The mysterious high galactic latitude cometary globule CG12 has been observed
with the ACIS detector on board the Chandra X-ray Observatory. We detect 128
X-ray sources; half are likely young stars formed within the globule's head.
This new population of >50 T-Tauri stars and one new embedded protostar is far
larger than the previously reported few intermediate-mass and two protostellar
members of the cloud. Most of the newly discovered stars have masses 0.2-0.7Mo,
and 9-15% have K-band excesses from inner protoplanetary disks. X-ray
properties provide an independent distance estimate consistent with CG12's
unusual location >200pc above the Galactic plane. The star formation efficiency
in CG12 appears to be 15-35%, far above that seen in other triggered molecular
globules. The median photometric age found for the T-Tauri population is ~4Myr
with a large spread of <1-20Myr and ongoing star formation in the molecular
cores. The stellar age and spatial distributions are inconsistent with a simple
radiation driven implosion (RDI) model, and suggest either that CG12 is an
atypically large shocked globule, or it has been subject to several distinct
episodes of triggering and ablation. We report a previously unnoticed group of
B-type stars northwest of CG12 which may be the remnants of an OB association
which produced multiple supernova explosions that could have shocked and
ablated the cloud over a 15-30Myr period. HD120958 (B3e), the most luminous
member of the group, may be currently driving an RDI shock into the CG12 cloud.


title: Bright-Dark Soliton Complexes in Spinor Bose-Einstein Condensates

abstract:
  We present bright-dark vector solitons in quasi-one-dimensional spinor (F=1)
Bose-Einstein condensates. Using a multiscale expansion technique, we reduce
the corresponding nonintegrable system of three coupled Gross-Pitaevskii
equations (GPEs) to a completely integrable Yajima-Oikawa system. In this way,
we obtain approximate solutions for small-amplitude vector solitons of
dark-dark-bright and bright-bright-dark types, in terms of the $m_{F}=+1,-1,0$
spinor components, respectively. By means of numerical simulations of the full
GPE system, we demonstrate that these states indeed feature soliton properties,
i.e., they propagate undistorted and undergo quasi-elastic collisions. It is
also shown that, in the presence of a parabolic trap of strength $\omega $, the
bright component(s) is (are) guided by the dark one(s), and, as a result, the
small-amplitude vector soliton as a whole performs harmonic oscillations of
frequency $\omega/ \sqrt{2}$ in the shallow soliton limit. We investigate
numerically deviations from this prediction, as the depth of the solitons is
increased, as well as when the strength of the spin-dependent interaction is
modified.


title: Planetary embryos and planetesimals residing in thin debris disks

abstract:
  We consider constraints on the planetesimal population residing in the disks
of AU Microscopii, Beta Pictoris and Fomalhaut taking into account their
observed thicknesses and normal disk opacities. We estimate that bodies of
radius 5, 180 and 70 km are responsible for initiating the collisional cascade
accounting for the dust production for AU-Mic, Beta-Pic and Fomalhaut's disks,
respectively, at break radii from the star where their surface brightness
profiles change slope. Larger bodies, of radius 1000km and with surface density
of order 0.01 g/cm^2, are required to explain the thickness of these disks
assuming that they are heated by gravitational stirring. A comparison between
the densities of the two sizes suggests the size distribution in the largest
bodies is flatter than that observed in the Kuiper belt. AU Mic's disk requires
the shallowest size distribution for bodies with radius greater than 10km
suggesting that the disk contains planetary embryos experiencing a stage of
runaway growth.


title: Lepton Flavour Violation in Unparticle Physics

abstract:
  Recently H. Georgi has introduced an unparticle $\unpart$ in order to
describe the low energy physics of a nontrivial scale invariant sector of an
effective theory. In this work we have explored the phenomenology of an
unparticle using the lepton flavour violating decay $\mu^{-}\to e^{-} e^{+}
e^{-}$, and found that the branching ratio of this decay is strongly dependent
on the scaling dimension.


title: Cooper-pair propagation and superconducting correlations in graphene

abstract:
  We investigate the Cooper-pair propagation and the proximity effect in
graphene under conditions in which the distance L between superconducting
electrodes is much larger than the width W of the contacts. In the case of
undoped graphene, supercurrents may exist with a spatial decay proportional to
W^2/L^3. This changes upon doping into a 1/L^2 behavior, opening the
possibility to observe a supercurrent over length scales above 1 micron at
suitable doping levels. We also show that there is in general a crossover
temperature T ~ v_F/k_B L that marks the onset of the strong decay of the
supercurrent, and that corresponds to the scale below which the Cooper pairs
are not disrupted by thermal effects during their propagation.


title:
Metal contacts in carbon nanotube field effect transistors: Beyond the
  Schottky barrier paradigm

abstract:
  The observed performances of carbon nanotube field effect transistors are
examined using first-principles quantum transport calculations. We focus on the
nature and role of the electrical contact of Au and Pd electrodes to open-ended
semiconducting nanotubes, allowing the chemical contact at the surface to fully
develop through large-scale relaxation of the contacting atomic configuration.
We present the first direct numerical evidence of Pd contacts exhibiting
perfect transparency for hole injection as opposed to that of Au contacts.
Their respective Schottky barrier heights, on the other hand, turn out to be
fairly similar for realistic contact models. These findings are in general
agreement with experimental data reported to date, and show that a Schottky
contact is not merely a passive ohmic contact but actively influences the
device I-V behavior.


title: Third Order Newton's Method for Zernike Polynomial Zeros

abstract:
  The Zernike radial polynomials are a system of orthogonal polynomials over
the unit interval with weight x. They are used as basis functions in optics to
expand fields over the cross section of circular pupils. To calculate the roots
of Zernike polynomials, we optimize the generic iterative numerical Newton's
Method that iterates on zeros of functions with third order convergence. The
technique is based on rewriting the polynomials as Gauss hypergeometric
functions, reduction of second order derivatives to first order derivatives,
and evaluation of some ratios of derivatives by terminating continued
fractions.
  A PARI program and a short table of zeros complete up to polynomials of 20th
order are included.


title: The soft-energy region in the radiative decay of bound states

abstract:
  The orthopositronium decay to three photons is studied in the phase-space
region where one of the photons has an energy comparable to the relative
three-momentum of the e+e- system (w ~ m alpha). The NRQED computation in this
regime shows that the dominant contribution arises from distances ~
1/(mw)^(1/2), which allows to treat the Coulomb interaction perturbatively. The
small-photon energy expansion of the 1-loop decay spectrum from full QED yields
the same result as the effective theory. By doing the threshold expansion of
the 1-loop QED amplitude we confirm that the leading term arises from a
loop-momentum region where q^0 ~ q^2/m ~ w. This corresponds to a new
non-relativistic loop-momentum region, which has to be taken into account for
the description of a non-relativistic particle-antiparticle system that decays
through soft photon emission.


title:
X-ray emissions from two-temperature accretion flows within a dipole
  magnetic funnel

abstract:
  We investigate the hydrodynamics of accretion channelled by a dipolar
magnetic field (funnel flows). We consider situations in which the electrons
and ions in the flow cannot maintain thermal equilibrium (two-temperature
effects) due to strong radiative loss, and determine the effects on the keV
X-ray properties of the systems. We apply this model to investigate the
accretion shocks of white dwarfs in magnetic cataclysmic variables. We have
found that the incorporation of two-temperature effects could harden the keV
X-rays. Also, the dipolar model yields harder X-ray spectra than the standard
planar model if white dwarf is sufficiently massive (>~1M_sun). When fitting
observed keV X-ray spectra of magnetic cataclysmic variables, the inclusion of
two-temperature hydrodynamics and a dipolar accretion geometry lowers estimates
for white-dwarf masses when compared with masses inferred from models excluding
these effects. We find mass reductions <~9% in the most massive cases.


title:
The Constraints Determining Forms of Entropy and Inducing Equilibrium
  Distributions

abstract:
  The ideas of the constraint-based statistics are introduced. The axiom and
six theorems of the constraint-based statistics are established.


title: Global Solutions to the Ultra-Relativistic Euler Equations

abstract:
  We prove a global existence theorem for the $3\times 3$ system of
relativistic Euler equations in one spacial dimension. It is shown that in the
ultra-relativistic limit, there is a family of equations of state that satisfy
the second law of thermodynamics for which solutions exist globally. With this
limit and equation of state, which includes equations of state for both an
ideal gas and one dominated by radiation, the relativistic Euler equations can
be analyzed by a Nishida-type method leading to a large data existence theorem,
including the entropy and particle number evolution, using a Glimm scheme. Our
analysis uses the fact that the equations of state are of the form $p=p(n,S)$,
but whose form simplifies to $p=a^{2}\rho$ when viewed as a function of $\rho$
alone.


title: Effective theories of gauge-Higgs unification models in warped spacetime

abstract:
  We derive four-dimensional (4D) effective theories of the gauge-Higgs
unification models in the warped spacetime. The effective action can be
expressed in a simple form by neglecting subleading corrections to the wave
functions. We have shown in our previous works that some Higgs couplings to the
other fields are suppressed by factors that depend on $\bar{\theta}_H$ from the
values in the standard model. Here $\bar{\theta}_H$ is the Wilson line phase
along the fifth dimension, which characterizes the electroweak symmetry
breaking. The effective action derived here explicitly shows a nonlinear
structure of the Higgs sector, which clarifies the origins of those suppression
factors.


title: Invertibility of the Gabor frame operator on the Wiener amalgam space

abstract:
  We use a generalization of Wiener's $1/f$ theorem to prove that for a Gabor
frame with the generator in the Wiener amalgam space $W(L^{\infty},
\ell^{1}_{\nu})(\mathbb{R}^{d})$, the corresponding frame operator is
invertible on this space. Therefore, for such a Gabor frame, the generator of
the canonical dual belongs also to $W(L^{\infty},
\ell^{1}_{\nu})(\mathbb{R}^{d}) $


title:
Diversity-Multiplexing Tradeoff via Asymptotic Analysis of Large MIMO
  Systems

abstract:
  Diversity-multiplexing tradeoff (DMT) presents a compact framework to compare
various MIMO systems and channels in terms of the two main advantages they
provide (i.e. high data rate and/or low error rate). This tradeoff was
characterized asymptotically (SNR-> infinity) for i.i.d. Rayleigh fading
channel by Zheng and Tse [1]. The asymptotic DMT overestimates the finite-SNR
one [2]. In this paper, using the recent results on the asymptotic (in the
number of antennas) outage capacity distribution, we derive and analyze the
finite-SNR DMT for a broad class of channels (not necessarily Rayleigh fading).
Based on this, we give the convergence conditions for the asymptotic DMT to be
approached by the finite-SNR one. The multiplexing gain definition is shown to
affect critically the convergence point: when the multiplexing gain is defined
via the mean (ergodic) capacity, the convergence takes place at realistic SNR
values. Furthermore, in this case the diversity gain can also be used to
estimate the outage probability with reasonable accuracy. The multiplexing gain
definition via the high-SNR asymptote of the mean capacity (as in [1]) results
in very slow convergence for moderate to large systems (as 1/ln(SNR)^2) and,
hence, the asymptotic DMT cannot be used at realistic SNR values. For this
definition, the high-SNR threshold increases exponentially in the number of
antennas and in the multiplexing gain. For correlated keyhole channel, the
diversity gain is shown to decrease with correlation and power imbalance of the
channel. While the SNR-asymptotic DMT of Zheng and Tse does not capture this
effect, the size-asymptotic DMT does.


title: Exploring Lifetime Effects in Femtoscopy

abstract:
  We investigate the role of lifetime effects from resonances and emission
duration tails in femtoscopy at RHIC in two Blast-Wave models. We find the
non-Gaussian components compare well with published source imaged data, but the
value of R_out obtained from Gaussian fits is not insensitive to the
non-Gaussian contributions when realistic acceptance cuts are applied to
models.


title: Lorentz-CPT violation, radiative corrections and finite temperature

abstract:
  In this work we investigate the radiatively induced Chern-Simons-like terms
in four-dimensions at zero and finite temperature. We use the approach of
rationalizing the fermion propagator up to the leading order in the
CPT-violating coupling $b_\mu$. In this approach, we have shown that although
the coefficient of Chern-Simons term can be found unambiguously in different
regularization schemes at zero or finite temperature, it remains undetermined.
We observe a correspondence among results obtained at finite and zero
temperature.


title:
The luminous X-ray hotspot in 4C 74.26: synchrotron or inverse-Compton
  emission?

abstract:
  We report the discovery of an X-ray counterpart to the southern radio hotspot
of the largest-known radio quasar 4C 74.26 (whose redshift is z=0.104). Both
XMM-Newton and Chandra images reveal the same significant (10arcsec, i.e.
19kpc) offset between the X-ray hotspot and the radio hotspot imaged with
MERLIN. The peak of the X-ray emission may be due to synchrotron or
inverse-Compton emission. If synchrotron emission, the hotspot represents the
site of particle acceleration and the offset arises from either the jet
exhibiting Scheuer's `dentist's drill' effect or a fast spine having less
momentum than the sheath surrounding it, which creates the radio hotspot. If
the emission arises from the inverse-Compton process, it must be
inverse-Compton scattering of the CMB in a decelerating relativistic flow,
implying that the jet is relativistic (Gamma >= 2) out to a distance of at
least 800kpc. Our analysis, including optical data from the Liverpool
Telescope, rules out a background AGN for the X-ray emission and confirms its
nature as a hotspot, making it the most X-ray luminous hotspot yet detected.


title: On Optimum Power Allocation for the V-BLAST

abstract:
  A unified analytical framework for optimum power allocation in the unordered
V-BLAST algorithm and its comparative performance analysis are presented.
Compact closed-form approximations for the optimum power allocation are
derived, based on average total and block error rates. The choice of the
criterion has little impact on the power allocation and, overall, the optimum
strategy is to allocate more power to lower step transmitters and less to
higher ones. High-SNR approximations for optimized average block and total
error rates are given. The SNR gain of optimization is rigorously defined and
studied using analytical tools, including lower and upper bounds, high and low
SNR approximations. The gain is upper bounded by the number of transmitters,
for any modulation format and type of fading channel. While the average
optimization is less complex than the instantaneous one, its performance is
almost as good at high SNR. A measure of robustness of the optimized algorithm
is introduced and evaluated. The optimized algorithm is shown to be robust to
perturbations in individual and total transmit powers. Based on the algorithm
robustness, a pre-set power allocation is suggested as a low-complexity
alternative to the other optimization strategies, which exhibits only a minor
loss in performance over the practical SNR range.


title: Experiments on Multidimensional Solitons

abstract:
  This article presents an overview of experimental efforts in recent years
related to multidimensional solitons in Bose-Einstein condensates. We discuss
the techniques used to generate and observe multidimensional nonlinear waves in
Bose-Einstein condensates with repulsive interactions. We further summarize
observations of planar soliton fronts undergoing the snake instability, the
formation of vortex rings, and the emergence of hybrid structures.


title: On the approximate normality of eigenfunctions of the Laplacian

abstract:
  The main result of this paper is a bound on the distance between the
distribution of an eigenfunction of the Laplacian on a compact Riemannian
manifold and the Gaussian distribution. If $X$ is a random point on a manifold
$M$ and $f$ is an eigenfunction of the Laplacian with $L^2$-norm one and
eigenvalue $-\mu$, then $$d_{TV}(f(X),Z)\le\frac{2}{\mu}\E\big|\|\nabla
f(X)\|^2-\E\|\nabla f(X) \|^2\big|.$$ This result is applied to construct
specific examples of spherical harmonics of arbitrary (odd) degree which are
close to Gaussian in distribution. A second application is given to random
linear combinations of eigenfunctions on flat tori.


title:
The Optimal Design of Three Degree-of-Freedom Parallel Mechanisms for
  Machining Applications

abstract:
  The subject of this paper is the optimal design of a parallel mechanism
intended for three-axis machining applications. Parallel mechanisms are
interesting alternative designs in this context but most of them are designed
for three- or six-axis machining applications. In the last case, the position
and the orientation of the tool are coupled and the shape of the workspace is
complex. The aim of this paper is to use a simple parallel mechanism with
two-degree-of-freedom (dof) for translational motions and to add one leg to
have one-dof rotational motion. The kinematics and singular configurations are
studied as well as an optimization method. The three-degree-of-freedom
mechanisms analyzed in this paper can be extended to four-axis machines by
adding a fourth axis in series with the first two.


title: Classification of one family of 3R positioning Manipulators

abstract:
  The aim of this paper is to classify one family of 3R serial positioning
manipulators. This categorization is based on the number of cusp points of
quaternary, binary, generic and non-generic manipulators. It was found three
subsets of manipulators with 0, 2 or 4 cusp points and one homotopy class for
generic quaternary manipulators. This classification allows us to define the
design parameters for which the manipulator is cuspidal or not, i.e., for which
the manipulator can or cannot change posture without meeting a singularity,
respectively.


title: Degree Optimization and Stability Condition for the Min-Sum Decoder

abstract:
  The min-sum (MS) algorithm is arguably the second most fundamental algorithm
in the realm of message passing due to its optimality (for a tree code) with
respect to the {\em block error} probability \cite{Wiberg}. There also seems to
be a fundamental relationship of MS decoding with the linear programming
decoder \cite{Koetter}. Despite its importance, its fundamental properties have
not nearly been studied as well as those of the sum-product (also known as BP)
algorithm.
  We address two questions related to the MS rule. First, we characterize the
stability condition under MS decoding. It turns out to be essentially the same
condition as under BP decoding. Second, we perform a degree distribution
optimization. Contrary to the case of BP decoding, under MS decoding the
thresholds of the best degree distributions for standard irregular LDPC
ensembles are significantly bounded away from the Shannon threshold. More
precisely, on the AWGN channel, for the best codes that we find, the gap to
capacity is 1dB for a rate 0.3 code and it is 0.4dB when the rate is 0.9 (the
gap decreases monotonically as we increase the rate).
  We also used the optimization procedure to design codes for modified MS
algorithm where the output of the check node is scaled by a constant
$1/\alpha$. For $\alpha = 1.25$, we observed that the gap to capacity was
lesser for the modified MS algorithm when compared with the MS algorithm.
However, it was still quite large, varying from 0.75 dB to 0.2 dB for rates
between 0.3 and 0.9.
  We conclude by posing what we consider to be the most important open
questions related to the MS algorithm.


title:
Power-law anisotropic cosmological solution in 5+1 dimensional
  Gauss-Bonnet gravity

abstract:
  We write down an anisotropic solution for a flat 5+1 dimensional Universe in
Gauss-Bonnet gravity. In the model under investigation this solution replaces
the generalized Kasner solution near a cosmological singularity.


title: Slow Convergence in Bootstrap Percolation

abstract:
  In the bootstrap percolation model, sites in an L by L square are initially
infected independently with probability p. At subsequent steps, a healthy site
becomes infected if it has at least 2 infected neighbours. As
(L,p)->(infinity,0), the probability that the entire square is eventually
infected is known to undergo a phase transition in the parameter p log L,
occurring asymptotically at lambda = pi^2/18. We prove that the discrepancy
between the critical parameter and its limit lambda is at least Omega((log
L)^(-1/2)). In contrast, the critical window has width only Theta((log
L)^(-1)). For the so-called modified model, we prove rigorous explicit bounds
which imply for example that the relative discrepancy is at least 1% even when
L = 10^3000. Our results shed some light on the observed differences between
simulations and rigorous asymptotics.


title: Semisimple Algebraic Groups in Characteristic Zero

abstract:
  It is shown that the classification theorems for semisimple algebraic groups
in characteristic zero can be derived quite simply and naturally from the
corresponding theorems for Lie algebras by using a little of the theory of
tensor categories. This article is extracted from Milne 2007.


title:
Phase coexistance in polydisperse mixture of hard-sphere colloidal and
  flexible chain particles

abstract:
  A theoretical scheme for the calculation of the full phase diagram (including
cloud and shadow curves, binodals and distribution functions of the coexisting
phases) for colloid-polymer mixtures with polymer chain length polydispersity
and hard-sphere colloidal and polymeric monomer sizes polydispersity is
proposed. The scheme combines thermodynamic perturbation theory for associating
fluids and recently developed method used to determine the phase diagram of
polydisperse spherical shape colloidal fluids (L.Bellier-Castella {\it et al.},
{\it J.Chem.Phys.} {\bf 113}, 8337(2000)). By way of illustration we present
and discuss the full phase diagram for the mixture with polydispersity in the
size of the hard-sphere colloidal particles.


title:
Generating Entangled Photons from the Vacuum by Accelerated
  Measurements: Quantum Information Theory Meets the Unruh-Davies Effect

abstract:
  Building on the well-known Unruh-Davies effect, we examine the effects of
projective measurements and quantum communications between accelerated and
stationary observers. We find that the projective measurement by a uniformly
accelerated observer can excite real particles from the vacuum in the inertial
frame, even if no additional particles are created by the measurement process
in the accelerating frame. Furthermore, we show that the particles created by
this accelerating measurement can be highly entangled in the inertial frame,
and it is also possible to use this process to generate even maximally
entangled two-qubit states by a certain arrangement of measurements. As a
byproduct of our analysis, we also show that a single qubit of information can
be perfectly transmitted from the accelerating observer to the inertial one. In
principle, such an effect could be exploited in designing an entangled state
generator for quantum communication.


title:
Reduced dimensionality in layered quantum dimer magnets: Frustration vs.
  inhomogeneous condensates

abstract:
  Motivated by recent experiments on BaCuSi2O6, we investigate magnetic
excitations and quantum phase transitions of layered dimer magnets with
inter-layer frustration. We consider two scenarios, (A) a lattice with one
dimer per unit cell and perfect inter-layer frustration, and (B) an enlarged
unit cell with inequivalent layers, with and without perfect frustration. In
all situations, the critical behavior at asymptotically low temperatures is
three-dimensional, but the corresponding crossover scale may be tiny. Magnetic
ordering in case (B) can be discussed in terms of two condensates; remarkably,
perfect frustration renders the proximity effect ineffective. Then, the
ordering transition will be generically split, with clear signatures in
measurable properties. Using a generalized bond-operator method, we calculate
the low-temperature magnetic properties in the paramagnetic and
antiferromagnetic phases. Based on the available experimental data on
BaCuSi2O6, we propose that scenario (B) with inequivalent layers and imperfect
frustration is realized in this material, likely with an additional modulation
of the inter-layer couling along the c axis.


title:
Energy dependence of jet transport parameter and parton saturation in
  quark-gluon plasma

abstract:
  We study the evolution and saturation of the gluon distribution function in
the quark-gluon plasma as probed by a propagating parton and its effect on the
computation of jet quenching or transport parameter $\hat{q}$. For thermal
partons, the saturation scale $Q^2_s$ is found to be proportional to the Debye
screening mass $\mu_D^2$. For hard probes, evolution at small $x=Q^2_s/6ET$
leads to jet energy dependence of $\hat{q}$. We study this dependence for both
a conformal gauge theory in weak and strong coupling limit and for (pure gluon)
QCD. The energy dependence can be used to extract the shear viscosity $\eta$ of
the medium since $\eta$ can be related to the transport parameter for thermal
partons in a transport description. We also derive upper bounds on the
transport parameter for both energetic and thermal partons. The later leads to
a lower bound on shear viscosity-to-entropy density ratio which is consistent
with the conjectured lower bound $\eta/s\geq 1/4\pi$. We also discuss the
implications on the study of jet quenching at the BNL Relativistic Heavy Ion
Collider and the CERN Large Hadron Collider and the bulk properties of the
dense matter.


title:
A Catalog of Absorption Lines in Eight HST/STIS E230M 1.0 < z < 1.7
  Quasar Spectra

abstract:
  We have produced a catalog of line identifications and equivalent width
measurements for all absorption features in eight ultraviolet echelle quasar
spectra. These spectra were selected as having the highest signal-to-noise
among the HST/STIS spectra obtained with the E230M grating. We identify 56
metal-line systems toward the eight quasars, and present plots of detected
transitions, aligned in velocity-space. We found that about 1/4 - 1/3 of the
features in the Lya forest region, redward of the incidence of the Lyb forest,
are metal lines. High ionization transitions are common. We see both O VI and C
IV in 88 - 90% of the metal-line systems for which the spectra cover the
expected wavelength. Si III is seen in 58%, while low ionization absorption in
C II, Si II, and/or Al II is detected in 50% of the systems for which they are
covered. This catalog will facilitate future studies of the Lya forest and of
metal-line systems of various types.


title: Spectral Properties of delta-Plutonium: Sensitivity to 5f Occupancy

abstract:
  By combining the local density approximation (LDA) with dynamical mean field
theory (DMFT), we report a systematic analysis of the spectral properties of
$\delta$-plutonium with varying $5f$ occupancy. The LDA Hamiltonian is
extracted from a tight-binding (TB) fit to full-potential linearized augmented
plane-wave (FP-LAPW) calculations. The DMFT equations are solved by the exact
quantum Monte Carlo (QMC) method and the Hubbard-I approximation. We have shown
for the first time the strong sensitivity of the spectral properties to the
$5f$ occupancy, which suggests using this occupancy as a fitting parameter in
addition to the Hubbard $U$. By comparing with PES data, we conclude that the
``open shell'' $5f^{5}$ configuration gives the best agreement, resolving the
controversy over $5f$ ``open shell'' versus ``close shell'' atomic
configurations in $\delta$-Pu.


title: K-band Imaging of strong CaII-absorber host galaxies at z~1

abstract:
  We present K-band imaging of fields around 30 strong CaII absorption line
systems, at 0.7<z<1.1, three of which are confirmed Damped Lyman-alpha systems.
A significant excess of galaxies is found within 6"0 (~50kpc) from the absorber
line-of-sight. The excess galaxies are preferentially luminous compared to the
population of field galaxies. A model in which field galaxies possess a
luminosity-dependent cross-section for CaII absorption of the form (L/L*)^0.7
reproduces the observations well. The luminosity-dependent cross-section for
the CaII absorbers appears to be significantly stronger than the established
(L/L*)^0.4 dependence for MgII absorbers. The associated galaxies lie at large
physical distances from the CaII-absorbing gas; we find a mean impact parameter
of 24kpc (H0=70km\s\Mpc). Combined with the observed number density of CaII
absorbers the large physical separations result in an inferred filling factor
of only ~10 per cent. The physical origin of the strong CaII absorption remains
unclear, possible explanations vary from very extended disks of the luminous
galaxies to associated dwarf galaxy neighbours, remnants of outflows from the
luminous galaxies, or tidal debris from cannibalism of smaller galaxies.


title: Missing Mass in Collisional Debris from Galaxies

abstract:
  Recycled dwarf galaxies can form in the collisional debris of massive
galaxies. Theoretical models predict that, contrary to classical galaxies, they
should be free of non-baryonic Dark Matter. Analyzing the observed gas
kinematics of such recycled galaxies with the help of a numerical model, we
demonstrate that they do contain a massive dark component amounting to about
twice the visible matter. Staying within the standard cosmological framework,
this result most likely indicates the presence of large amounts of unseen,
presumably cold, molecular gas. This additional mass should be present in the
disks of their progenitor spiral galaxies, accounting for a significant part of
the so-called missing baryons.


title: Do the QCD sum rules support four-quark states?

abstract:
  We test the validity of the QCD sum rules applied to the light scalar mesons,
the charmed mesons $D_{s0}(2317)$ and $D_{s1} (2460)$, and the X(3872) axial
meson, considered as tetraquark states. We find that, with the studied
currents, it is possible to find an acceptable Borel window only for the
X(3872) meson. In such a Borel window we have simultaneouly a good OPE
convergence and a pole contribution which is bigger than the continuum
contribution. We interpret these results as a strong argument against the
assignment of a tetraquark structure for the light scalars and the
$D_{s0}(2317)$ and $D_{s1} (2460)$ mesons.


title:
Experimental approaches to the difference in the Casimir force through
  the varying optical properties of boundary surface

abstract:
  We propose two novel experiments on the measurement of the Casimir force
acting between a gold coated sphere and semiconductor plates with markedly
different charge carrier densities. In the first of these experiments a
patterned Si plate is used which consists of two sections of different dopant
densities and oscillates in the horizontal direction below a sphere. The
measurement scheme in this experiment is differential, i.e., allows the direct
high-precision measurement of the difference of the Casimir forces between the
sphere and sections of the patterned plate or the difference of the equivalent
pressures between Au and patterned parallel plates with static and dynamic
techniques, respectively. The second experiment proposes to measure the Casimir
force between the same sphere and a VO${}_2$ film which undergoes the
insulator-metal phase transition with the increase of temperature. We report
the present status of the interferometer based variable temperature apparatus
developed to perform both experiments and present the first results on the
calibration and sensitivity. The magnitudes of the Casimir forces and pressures
in the experimental configurations are calculated using different theoretical
approaches to the description of optical and conductivity properties of
semiconductors at low frequencies proposed in the literature. It is shown that
the suggested experiments will aid in the resolution of theoretical problems
arising in the application of the Lifshitz theory at nonzero temperature to
real materials. They will also open new opportunities in nanotechnology.


title: Puncture Evolution of Schwarzschild Black Holes

abstract:
  The moving puncture method is analyzed for a single, non-spinning black hole.
It is shown that the puncture region is not resolved by current numerical
codes. As a result, the geometry near the puncture appears to evolve to an
infinitely long cylinder of finite areal radius. The puncture itself actually
remains at spacelike infinity throughout the evolution. In the limit of
infinite resolution the data never become stationary. However, at any
reasonable finite resolution the grid points closest to the puncture are
rapidly drawn into the black hole interior by the Gamma-driver shift condition.
The data can then evolve to a stationary state. These results suggest that the
moving puncture technique should be viewed as a type of "natural excision".


title:
Dynamics of quantum spin liquid and spin solid phases in IPA-CuCl3 under
  field

abstract:
  Inelastic and elastic neutron scattering is used to study spin correlations
in the quasi-one dimensional quantum antiferromagnet IPA-CuCl3 in strong
applied magnetic fields. A condensation of magnons and commensurate transverse
long-range ordering is observe at a critical filed $H_c=9.5$ T. The field
dependencies of the energies and polarizations of all magnon branches are
investigated both below and above the transition point. Their dispersion is
measured across the entire 1D Brillouin zone in magnetic fields up to 14 T. The
critical wave vector of magnon spectrum truncation [Masuda et al., Phys. Rev.
Lett. 96, 047210 (2006)] is found to shift from h_c 0.35 at H>H_c. A drastic
reduction of magnon bandwidths in the ordered phase [Garlea et al., Phys. Rev.
Lett. 98, 167202 (2007)] is observed and studied in detail. New features of the
spectrum, presumably related to this bandwidth collapse, are observed just
above the transition field.


title:
Nonradiative DKR processes: revisiting the theory. II.
  Electron-vibrational mode coupling

abstract:
  We summarize a few proposals for mixing F center states through the mediation
of an appropriate symmetry-breaking vibrational mode. Electron-mode coupling
energies odd-order in the mode coordinates are characteristic of the
pseudo-Jahn-Teller mixing of nearly-degenerate opposite-parity electronic
states mediated by an odd-parity vibrational mode. Coupling energies even order
in the vibrational coordinates lead to a pseudo-Renner mixing of even parity
nearly-degenerate states or to dynamic-Renner mixing of degenerate states of
whatever symmetry. Both Renner mixing energies add up to widen the crossover
splitting of the adiabatic energies thereby enhancing the nonradiative
deexcitation rate.


title: Studies of EGRET sources with a novel image restoration technique

abstract:
  We have developed an image restoration technique based on the Richardson-Lucy
algorithm optimized for GLAST-LAT image analysis. Our algorithm is original
since it utilizes the PSF (point spread function) that is calculated for each
event. This is critical for EGRET and GLAST-LAT image analysis since the PSF
depends on the energy and angle of incident gamma-rays and varies by more than
one order of magnitude. EGRET and GLAST-LAT image analysis also faces Poisson
noise due to low photon statistics. Our technique incorporates wavelet
filtering to minimize noise effects. We present studies of EGRET sources using
this novel image restoration technique for possible identification of extended
gamma-ray sources.


abstract:
  In this paper I discuss Enrico Fermi's view of identical particles, taking a
lecture that he gave in 1933 as a starting point. Fermi used his lecture as a
basis for a paper that was published in 1934: the paper is in italian and is
not easily accessible to a wide audience, and for this reason its translation
is also given in a section of the present paper.


title: An Approximation Algorithm for Shortest Descending Paths

abstract:
  A path from s to t on a polyhedral terrain is descending if the height of a
point p never increases while we move p along the path from s to t. No
efficient algorithm is known to find a shortest descending path (SDP) from s to
t in a polyhedral terrain. We give a simple approximation algorithm that solves
the SDP problem on general terrains. Our algorithm discretizes the terrain with
O(n^2 X / e) Steiner points so that after an O(n^2 X / e * log(n X /e))-time
preprocessing phase for a given vertex s, we can determine a (1+e)-approximate
SDP from s to any point v in O(n) time if v is either a vertex of the terrain
or a Steiner point, and in O(n X /e) time otherwise. Here n is the size of the
terrain, and X is a parameter of the geometry of the terrain.


title:
Multi-wavelength analysis of 18um-selected galaxies in the AKARI/IRC
  monitor field towards the North Ecliptic Pole

abstract:
  We present an initial analysis of AKARI 18um-selected galaxies using all 9
photometric bands at 2-24um available in the InfraRed Camera (IRC), in order to
demonstrate new capabilities of AKARI cosmological surveys. We detected 72
sources at 18um in an area of 50.2 arcmin^2 in the AKARI/IRC monitor field
towards the North Ecliptic Pole (NEP). From this sample, 25 galaxies with
probable redshifts z>~ 0.5 are selected with a single colour cut (N2-N3>0.1)
for a detailed SED analysis with ground-based BVRi'z'JK data. Using an SED
radiative transfer model of starbursts covering the wavelength range UV --
submm, we derive photometric redshifts from the optical-MIR SEDs of
18um-selected galaxies. From the best-fit SED models, we show that the IRC
all-band photometry is capable of tracing the steep rise in flux at the blue
side of the PAH 6.2um emission feature. This indicates that the IRC all-band
photometry is useful to constrain the redshift of infrared galaxies,
specifically for dusty galaxies with a less prominent 4000A break. Also, we
find that the flux dip between the PAH 7.7 and 11.2um emission feature is
recognizable in the observed SEDs of galaxies at z~1. By using such a colour
anomaly due to the PAH and silicate absorption features, unique samples of
ULIRGs at z~1, `silicate-break' galaxies, can be constructed from large
cosmological surveys of AKARI towards the NEP, i.e. the NEP-Deep and NEP-Wide
survey. This pilot study suggests the possibility of detecting many interesting
galaxy properties in the NEP-Deep and Wide surveys, such as a systematic
difference in SEDs between high- and low-z ULIRGs, and a large variation of the
PAH inter-band strength ratio in galaxies at high redshifts. [abridged]


title: Sfermion Interference in Neutralino Decays at the LHC

abstract:
  If the two lightest neutralinos of the Minimal Supersymmetric Standard Model
have a mass splitting less than the Z boson mass, interference effects in the
three-body decay chi_2^0 --> chi_1^0 f f can be important. We formulate an
observable that contains information on the nature of the interference: the
ratio BR(chi_2^0 --> chi_1^0 b b) / BR(chi_2^0 --> chi_1^0 l+ l-). This will
give a constraint on the supersymmetry breaking parameters that is
complementary to many techniques already existing in the literature. We present
some ideas on how to perform a simple counting experiment to determine this
ratio.


title: Logic Column 18: Alternative Logics: A Book Review

abstract:
  This article discusses two books on the topic of alternative logics in
science: "Deviant Logic", by Susan Haack, and "Alternative Logics: Do Sciences
Need Them?", edited by Paul Weingartner.


title: Link Homologies and the Refined Topological Vertex

abstract:
  We establish a direct map between refined topological vertex and sl(N)
homological invariants of the of Hopf link, which include Khovanov-Rozansky
homology as a special case. This relation provides an exact answer for
homological invariants of the of Hopf link, whose components are colored by
arbitrary representations of sl(N). At present, the mathematical formulation of
such homological invariants is available only for the fundamental
representation (the Khovanov-Rozansky theory) and the relation with the refined
topological vertex should be useful for categorifying quantum group invariants
associated with other representations (R_1, R_2). Our result is a first direct
verification of a series of conjectures which identifies link homologies with
the Hilbert space of BPS states in the presence of branes, where the physical
interpretation of gradings is in terms of charges of the branes ending on
Lagrangian branes.


title: Interacting Constituents in Cosmology

abstract:
  Universe evolution, as described by Friedmann's equations, is determined by
source terms fixed by the choice of pressure $\times$ energy-density equations
of state $p(\rho)$. The usual approach in Cosmology considers equations of
state accounting only for kinematic terms, ignoring the contribution from the
interactions between the particles constituting the source fluid. In this work
the importance of these neglected terms is emphasized. A systematic method,
based on the Statistical Mechanics of real fluids, is proposed to include them.
A toy-model is presented which shows how such interaction terms can engender
significant cosmological effects.


title: Can quantum correlations be completely quantum?

abstract:
  Deficit of information zero-way was proposed in HorodeckiHHOSSS2005 as one of
possible measures of quantumness of correlations. Numerical calculations
suggested that there exist such states for which this quantity is almost equal
to mutual information. In this paper we present a family of states for which we
have equality between above measure of quantumness of correlations and the
measure of total correlations -- mutual information. It means that whole
correlations in these states have, in some sense, quantum character and that
quantum correlations do not necessarily imply classical correlations. We prove
this intriguing feature for a subclass of 2x2 separable states. We also present
numerical result suggesting that this interesting situation might also happen
for 2x2 entangled states.


title: Isolated horizons in higher-dimensional Einstein-Gauss-Bonnet gravity

abstract:
  The isolated horizon framework was introduced in order to provide a local
description of black holes that are in equilibrium with their (possibly
dynamic) environment. Over the past several years, the framework has been
extended to include matter fields (dilaton, Yang-Mills etc) in D=4 dimensions
and cosmological constant in $D\geq3$ dimensions. In this article we present a
further extension of the framework that includes black holes in
higher-dimensional Einstein-Gauss-Bonnet (EGB) gravity. In particular, we
construct a covariant phase space for EGB gravity in arbitrary dimensions which
allows us to derive the first law. We find that the entropy of a weakly
isolated and non-rotating horizon is given by
$\mathcal{S}=(1/4G_{D})\oint_{S^{D-2}}\bm{\tilde{\epsilon}}(1+2\alpha\mathcal{R})$.
In this expression $S^{D-2}$ is the $(D-2)$-dimensional cross section of the
horizon with area form $\bm{\tilde{\epsilon}}$ and Ricci scalar $\mathcal{R}$,
$G_{D}$ is the $D$-dimensional Newton constant and $\alpha$ is the Gauss-Bonnet
parameter. This expression for the horizon entropy is in agreement with those
predicted by the Euclidean and Noether charge methods. Thus we extend the
isolated horizon framework beyond Einstein gravity.


title: Quantum Markovian Subsystems: Invariance, Attractivity, and Control

abstract:
  We characterize the dynamical behavior of continuous-time, Markovian quantum
systems with respect to a subsystem of interest. Markovian dynamics describes a
wide class of open quantum systems of relevance to quantum information
processing, subsystem encodings offering a general pathway to faithfully
represent quantum information. We provide explicit linear-algebraic
characterizations of the notion of invariant and noiseless subsystem for
Markovian master equations, under different robustness assumptions for
model-parameter and initial-state variations. The stronger concept of an
attractive quantum subsystem is introduced, and sufficient existence conditions
are identified based on Lyapunov's stability techniques. As a main control
application, we address the potential of output-feedback Markovian control
strategies for quantum pure state-stabilization and noiseless-subspace
generation. In particular, explicit results for the synthesis of stabilizing
semigroups and noiseless subspaces in finite-dimensional Markovian systems are
obtained.


title:
A Comprehensive Analysis of the Swift/XRT Data: II. Diverse Physical
  Origins of the Shallow Decay Segment

abstract:
  We analyze the properties of the shallow decay segment with a sample of 53
long Swift GRBs. We show that the distributions of its characteristics are
log-normal or normal, and its isotropic X-ray energy (E_{iso,X}) is linearly
correlated with the prompt gamma-ray energy, but with a steeper photon spectrum
except for some X-ray flashes. No significant spectral evolution is observed
from this phase to the follow-up phase, and the follow-up phase is usually
consistent with the external shock models, implying that this segment likely
due to a refreshed external shock. Within this scenario, the data are generally
consistent with a roughly constant injection luminosity up to the end of this
phase $t_b$. A positive correlation between E_{iso, X} and t_b also favors this
scenario. Among the 13 bursts that have well-sampled optical light curves, 6
have an optical break around t_b and the breaks are consistent with being
achromatic. However, the other 7 bursts either do not show an optical break or
have a break at a different epoch than t_b. This raises a concern to the energy
injection scenario, suggesting that the optical and X-ray emissions may not be
the same component at least for a fraction of bursts. There are 4 significant
outliers in the sample, and this shallow decau phase in these bursts is
immediately followed by a very steep decay after t_b, which is inconsistent
with any external shock model. The optical data of these bursts evolve
independently from the X-ray data. These X-ray plateaus likely have an internal
origin and demand continuous operation of a long-term GRB central engine. We
conclude that the observed shallow decay phase likely has diverse physical
origins(Abridged).


title: Black hole mass estimates from soft X-ray spectra

abstract:
  In the absence of direct kinematic measurements, the mass of an accreting
black hole is sometimes inferred from the X-ray spectral parameters of its
accretion disk; specifically, from the temperature and normalization of a
disk-blackbody model fit. Suitable corrections have to be introduced when the
accretion rate approaches or exceeds the Eddington limit. We summarize
phenomenological models that can explain the very high state, with apparently
higher disk temperatures and lower inner-disk radii. Conversely, ultraluminous
X-ray sources often contain cooler disks with large characteristic radii. We
introduce another phenomenological model for this accretion state. We argue
that a standard disk dominates the radiative output for radii larger than a
characteristic transition radius R_c ~ mdot x R_{ISCO}, where mdot is the
accretion rate in Eddington units and R_{ISCO} is the innermost stable orbit.
For R_{ISCO} < R < R_c, most of the accretion power is released via non-thermal
processes. We predict the location of such sources in a luminosity-temperature
plot. We conclude that black holes with masses ~ 50-100 Msun accreting at mdot
~ 10-20 may explain the X-ray properties of many ULXs.


title: Thom polynomials and Schur functions: the singularities I_{2,2}(-)

abstract:
  We give the Thom polynomials for the singularities $I_{2,2}$ associated with
maps $({\bf C}^{\bullet},0) \to ({\bf C}^{\bullet+k},0)$ with parameter $k\ge
0$. Our computations combine the characterization of Thom polynomials via the
``method of restriction equations'' of Rimanyi et al. with the techniques of
Schur functions.


title: Observations of solar-like oscillations

abstract:
  There has been tremendous progress in observing oscillations in solar-type
stars. In a few short years we have moved from ambiguous detections to firm
measurements. We briefly review the recent results, most of which have come
from high-precision Doppler measurements. We also review briefly the results on
giant and supergiant stars and the prospects for the future.


title: Dynamic Screening in a Two-Species Asymmetric Exclusion Process

abstract:
  The dynamic scaling properties of the one dimensional Burgers equation are
expected to change with the inclusion of additional conserved degrees of
freedom. We study this by means of 1-D driven lattice gas models that conserve
both mass and momentum. The most elementary version of this is the
Arndt-Heinzel-Rittenberg (AHR) process, which is usually presented as a two
species diffusion process, with particles of opposite charge hopping in
opposite directions and with a variable passing probability.
  From the hydrodynamics perspective this can be viewed as two coupled Burgers
equations, with the number of positive and negative momentum quanta
individually conserved. We determine the dynamic scaling dimension of the AHR
process from the time evolution of the two-point correlation functions, and
find numerically that the dynamic critical exponent is consistent with simple
Kardar-Parisi-Zhang (KPZ) type scaling. We establish that this is the result of
perfect screening of fluctuations in the stationary state. The two-point
correlations decay exponentially in our simulations and in such a manner that
in terms of quasi-particles, fluctuations fully screen each other at coarse
grained length scales. We prove this screening rigorously using the analytic
matrix product structure of the stationary state. The proof suggests the
existence of a topological invariant. The process remains in the KPZ
universality class but only in the sense of a factorization, as $({KPZ})^2$.
The two Burgers equations decouple at large length scales due to the perfect
screening.


title: A Pair of Bootes: A New Milky Way Satellite

abstract:
  As part of preparations for a southern sky search for faint Milky Way dwarf
galaxy satellites, we report the discovery of a stellar overdensity in the
Sloan Digital Sky Survey Data Release 5, lying at an angular distance of only
1.5 degrees from the recently discovered Bo{\"o}tes dwarf. The overdensity was
detected well above statistical noise by employing a sophisticated data mining
algorithm and does not correspond to any catalogued object. Overlaid isochrones
using stellar population synthesis models show that the color-magnitude diagram
of that region has the signature of an old (12 Gyr), metal-poor (${\rm
Fe/H}\approx-2.0$) stellar population at a tentative distance of 60 kpc,
evidently the same heliocentric distance as the Bo\"otes dwarf. We estimate the
new object to have a total magnitude of $M_{V}\sim-3.1\pm1.1$ mag and a
half-light radius of $r_{h}=4'.1\pm1'.6$ ($72\pm28$ pc) placing it in an
apparent $40<r_{h}<100$ pc void between globular clusters and dwarf galaxies,
occupied only by another recently discovered Milky Way Satellite, Coma
Berenices.


title:
The Average Kinetic Energy of the Heavy Quark in $\Lambda_b$ in the
  Bethe-Salpeter Equation Approach

abstract:
  In the previous paper, based on the $SU(2)_{f}\times SU(2)_{s}$ heavy quark
symmetries of the QCD Lagrangian in the heavy quark limit, the Bethe-Salpeter
equation for the heavy baryon $\Lambda_b$ was established with the picture that
$\Lambda_b$ is composed of a heavy quark and a scalar light diquark. In the
present work, we apply this model to calculate $\mu_\pi^2$ for $\Lambda_b$, the
average kinetic energy of the heavy quark inside $\Lambda_{b}$. This quantity
is particularly interesting since it can be measured in experiments and since
it contributes to the inclusive semileptonic decays of $\Lambda_b$ when
contributions from higher order terms in $1/M_b$ expansions are taken into
account and consequently influences the determination of the
Cabibbo-Kobayashi-Maskawa matrix elements $V_{ub}$ and $V_{cb}$. We find that
$\mu_\pi^2$ for $\Lambda_b$ is $0.25GeV^2$ $\sim$ $0.95GeV^2$, depending on the
parameters in the model including the light diquark mass and the interaction
strength between the heavy quark and the light diquark in the kernel of the BS
equation. We also find that this result is consistent with the value of
$\mu_\pi^2$ for $\Lambda_b$ which is derived from the experimental value of
$\mu_\pi^2$ for the $B$ meson with the aid of the heavy quark effective theory.


title: A Josephson Junction Microscope for Low-frequency Fluctuators

abstract:
  The high-Q harmonic oscillator mode of a Josephson junction can be used as a
novel probe of spurious two-level systems (TLSs) inside the amorphous oxide
tunnel barriers of the junction. In particular, we show that spectroscopic
transmission measurements of the junction resonator mode can reveal how the
coupling magnitude between the junction and the TLSs varies with an external
magnetic field applied in the plane of the tunnel barrier. The proposed
experiments offer the possibility of clearly resolving the underlying coupling
mechanism for these spurious TLSs, an important decoherence source limiting the
quality of superconducting quantum devices.


title: On Two of Erd\"os's Open Problems

abstract:
  In this short note we present some remarks and conjectures on two of
Erd\"os's open problems in number theory.


title:
Antiferromagnetic Spin Fluctuations in the Metallic Phase of
  Quasi-Two-Dimensional Organic Superconductors

abstract:
  We give a quantitative analysis of the previously published nuclear magnetic
resonance (NMR) experiments in the k-(ET)2X family of organic charge transfer
salts by using the phenomenological spin fluctuation model of Moriya, and
Millis, Monien and Pines (M-MMP). For temperatures above T_nmr ~ 50 K, the
model gives a good quantitative description of the data in the metallic phases
of several k-(ET)2X materials. These materials display antiferromagnetic
correlation lengths which increase with decreasing temperature and grow to
several lattice constants by T_nmr. It is shown that the fact that the
dimensionless Korringa ratio is much larger than unity is inconsistent with a
broad class of theoretical models (such as dynamical mean-field theory) which
neglects spatial correlations and/or vertex corrections. For materials close to
the Mott insulating phase the nuclear spin relaxation rate, the Knight shift
and the Korringa ratio all decrease significantly with decreasing temperature
below T_nmr. This cannot be described by the M-MMP model and the most natural
explanation is that a pseudogap, similar to that observed in the underdoped
cuprate superconductors, opens up in the density of states below T_nmr. Such a
pseudogap has recently been predicted to occur in the dimerised organic charge
transfer salts materials by the resonating valence bond (RVB) theory. We
propose specific new experiments on organic superconductors to elucidate these
issues. For example, measurements to see if high magnetic fields or high
pressures can be used to close the pseudogap would be extremely valuable.


title:
The effect of randomness on the quantum spin system
  Tl$_{1-x}$K$_x$CuCl$_3$ with ${\boldmath $x$}$ = 0.44 studied by the
  Zero-field Muon-Spin-Relaxation (ZF-$\mu$SR) method

abstract:
  Zero-field muon-spin-relaxation (ZF-{\boldmath $\mu$}SR) measurements were
carried out down to 80 mK on the randomness bond system Tl$_{1-x}$K$_x$CuCl$_3$
with $x$ = 0.44. Time spectra are well fitted by the stretched exponential
function $\exp (-\lambda t)^{\beta}$. The muon spin relaxation rate $\lambda$
increases rapidly with decreasing temperature, and $\beta$ tends to 0.5 at 80
mK. The divergent increase of $\lambda$ suggests the critical slowing down of
the frequency of the Cu-3{\it d} spin fluctuations toward a spin frozen state
below 80 mK, and the root-exponential-like behavior of the time spectrum
indicates that the origin of the relaxation is possibly the spatially-fixed
fluctuating dilute moments.


title: Matroid Pathwidth and Code Trellis Complexity

abstract:
  We relate the notion of matroid pathwidth to the minimum trellis
state-complexity (which we term trellis-width) of a linear code, and to the
pathwidth of a graph. By reducing from the problem of computing the pathwidth
of a graph, we show that the problem of determining the pathwidth of a
representable matroid is NP-hard. Consequently, the problem of computing the
trellis-width of a linear code is also NP-hard. For a finite field $\F$, we
also consider the class of $\F$-representable matroids of pathwidth at most
$w$, and correspondingly, the family of linear codes over $\F$ with
trellis-width at most $w$. These are easily seen to be minor-closed. Since
these matroids (and codes) have branchwidth at most $w$, a result of Geelen and
Whittle shows that such matroids (and the corresponding codes) are
characterized by finitely many excluded minors. We provide the complete list of
excluded minors for $w=1$, and give a partial list for $w=2$.


title: Bell inequalities for continuous-variable correlations

abstract:
  We derive a new class of correlation Bell-type inequalities. The inequalities
are valid for any number of outcomes of two observables per each of n parties,
including continuous and unbounded observables. We show that there are no
first-moment correlation Bell inequalities for that scenario, but such
inequalities can be found if one considers at least second moments. The
derivation stems from a simple variance inequality by setting local commutators
to zero. We show that above a constant detector efficiency threshold, the
continuous variable Bell violation can survive even in the macroscopic limit of
large n. This method can be used to derive other well-known Bell inequalities,
shedding new light on the importance of non-commutativity for violations of
local realism.


title: Quantum cohomology of G/P and homology of affine Grassmannian

abstract:
  Let G be a simple and simply-connected complex algebraic group, P \subset G a
parabolic subgroup. We prove an unpublished result of D. Peterson which states
that the quantum cohomology QH^*(G/P) of a flag variety is, up to localization,
a quotient of the homology H_*(Gr_G) of the affine Grassmannian \Gr_G of G. As
a consequence, all three-point genus zero Gromov-Witten invariants of $G/P$ are
identified with homology Schubert structure constants of H_*(Gr_G),
establishing the equivalence of the quantum and homology affine Schubert
calculi.
  For the case G = B, we use the Mihalcea's equivariant quantum Chevalley
formula for QH^*(G/B), together with relationships between the quantum Bruhat
graph of Brenti, Fomin and Postnikov and the Bruhat order on the affine Weyl
group. As byproducts we obtain formulae for affine Schubert homology classes in
terms of quantum Schubert polynomials. We give some applications in quantum
cohomology.
  Our main results extend to the torus-equivariant setting.


title:
Nature of Infrared Sources in 11 micron Selected Sample from Early Data
  of the AKARI North Ecliptic Pole Deep Survey

abstract:
  We present the properties of 11 $\mu$m selected sources detected in the early
data of the North Ecliptic Pole Deep (NEP-Deep) Survey of AKARI. The data set
covers 6 wavelength bands from 2.5 to 11 $\mu$m, with the exposure time of 10 ~
20 minutes. This field lies within the CFHT survey with four filter bands ($g',
r', i',z'), enabling us to establish nearly continuous spectral energy
distributions (SEDs) for wavelengths ranging from 0.4 to 11 $\mu$m. The main
sample studied here consists of 71 sources whose 11 $\mu$m AB magnitudes are
equal to or brighter than 18.5 (251 $\mu$Jy), which is complete to more than
90%. The 11 $\mu$m band has an advantage of sampling star forming galaxies with
low to medium redshifts since the prominent PAH feature shifts into this band.
As expected, we find that the majority (~68%) of 11 $\mu$m bright sources are
star forming galaxies at 0.2 < z < 0.7 with $L_{IR} ~ 10^{10}$ -- $10^{12}
L_{\odot}$ based on the detailed modelling of SEDs. We also find four AGNs
lying at various redshifts in the main sample. In addition, we discuss a few
sources which have non-typical SEDs of the main sample, including a brown dwarf
candidate, a steep power-law source, flat spectrum object, and an early-type
galaxy at moderate redshift.


title:
Some properties of the resonant state in quantum mechanics and its
  computation

abstract:
  The resonant state of the open quantum system is studied from the viewpoint
of the outgoing momentum flux. We show that the number of particles is
conserved for a resonant state, if we use an expanding volume of integration in
order to take account of the outgoing momentum flux; the number of particles
would decay exponentially in a fixed volume of integration. Moreover, we
introduce new numerical methods of treating the resonant state with the use of
the effective potential. We first give a numerical method of finding a
resonance pole in the complex energy plane. The method seeks an energy
eigenvalue iteratively. We found that our method leads to a super-convergence,
the convergence exponential with respect to the iteration step. The present
method is completely independent of commonly used complex scaling. We also give
a numerical trick for computing the time evolution of the resonant state in a
limited spatial area. Since the wave function of the resonant state is
diverging away from the scattering potential, it has been previously difficult
to follow its time evolution numerically in a finite area.

categories: quant-ph cond-mat.mes-hall cond-mat.stat-mech nucl-th physics.atom-ph


title:
Effects of the DNA state fluctuation on single-cell dynamics of
  self-regulating gene

abstract:
  A dynamical mean-field theory is developed to analyze stochastic single-cell
dynamics of gene expression. By explicitly taking account of nonequilibrium and
nonadiabatic features of the DNA state fluctuation, two-time correlation
functions and response functions of single-cell dynamics are derived. The
method is applied to a self-regulating gene to predict a rich variety of
dynamical phenomena such as anomalous increase of relaxation time and
oscillatory decay of correlations. Effective "temperature" defined as the ratio
of the correlation to the response in the protein number is small when the DNA
state change is frequent, while it grows large when the DNA state change is
infrequent, indicating the strong enhancement of noise in the latter case.


title:
Machine and Component Residual Life Estimation through the Application
  of Neural Networks

abstract:
  This paper concerns the use of neural networks for predicting the residual
life of machines and components. In addition, the advantage of using
condition-monitoring data to enhance the predictive capability of these neural
networks was also investigated. A number of neural network variations were
trained and tested with the data of two different reliability-related datasets.
The first dataset represents the renewal case where the failed unit is repaired
and restored to a good-as-new condition. Data was collected in the laboratory
by subjecting a series of similar test pieces to fatigue loading with a
hydraulic actuator. The average prediction error of the various neural networks
being compared varied from 431 to 841 seconds on this dataset, where test
pieces had a characteristic life of 8,971 seconds. The second dataset was
collected from a group of pumps used to circulate a water and magnetite
solution within a plant. The data therefore originated from a repaired system
affected by reliability degradation. When optimized, the multi-layer perceptron
neural networks trained with the Levenberg-Marquardt algorithm and the general
regression neural network produced a sum-of-squares error within 11.1% of each
other. The potential for using neural networks for residual life prediction and
the advantage of incorporating condition-based data into the model were proven
for both examples.


title: Fermions, scalars and Randall-Sundrum gravity on domain-wall branes

abstract:
  We analyse the general features of localisation of fermions and scalars in
smoothed field-theoretical versions of the type 2 Randall- Sundrum braneworld
model. A scalar field domain-wall forms the brane, inducing warped gravity, and
we study the mass spectra of the matter fields in the dimensionally reduced
theory. We demonstrate explicitly that both scalar and fermion fields exhibit a
continuum of properly normalisable modes starting at zero mass. If discrete
bound modes are present in the gravity-free case, these become resonances in
the continuum, while off-resonant modes are highly suppressed on the brane. We
describe briefly how another scalar field can be used to break a symmetry on
the domain-wall while leaving it unbroken far from the wall, as has already
been done in the flat space case. Finally we present numerical calculations for
a toy model which demonstrates the decoupling of continuum modes at low
energies, so the theory becomes four dimensional.


title: The spectral shift function and spectral flow

abstract:
  This paper extends Krein's spectral shift function theory to the setting of
semifinite spectral triples. We define the spectral shift function under these
hypotheses via Birman-Solomyak spectral averaging formula and show that it
computes spectral flow.


title: Photodetachment of H$^{-}$ near a partial reflecting surface

abstract:
  Theoretical and interpretative study on the subject of photodetachment of
H$^{-}$ near a partial reflecting surface is presented, and the absorption
effect of the surface is investigated on the total and differential cross
sections using a theoretical imaging method. To understand the absorption
effect, a reflection parameter $K$ is introduced as a multiplicative factor to
the outgoing detached-electron wave of H$^-$ propagating toward the wall. The
reflection parameter measures, how much electron wave would reflect from the
surface; K=0 corresponds to no reflection and K=1 corresponds to the total
reflection.


title: The Orthoglide: Kinematics and Workspace Analysis

abstract:
  The paper addresses kinematic and geometrical aspects of the Orthoglide, a
three-DOF parallel mechanism. This machine consists of three fixed linear
joints, which are mounted orthogonally, three identical legs and a mobile
platform, which moves in the Cartesian x-y-z space with fixed orientation. New
solutions to solve inverse/direct kinematics are proposed and a detailed
workspace analysis is performed taking into account specific joint limit
constraints.


title: Subjective Evaluation of Forms in an Immersive Environment

abstract:
  User's perception of product, by essence subjective, is a major topic in
marketing and industrial design. Many methods, based on users' tests, are used
so as to characterise this perception. We are interested in three main methods:
multidimensional scaling, semantic differential method, and preference mapping.
These methods are used to built a perceptual space, in order to position the
new product, to specify requirements by the study of user's preferences, to
evaluate some product attributes, related in particular to style (aesthetic).
These early stages of the design are primordial for a good orientation of the
project. In parallel, virtual reality tools and interfaces are more and more
efficient for suggesting to the user complex feelings, and creating in this way
various levels of perceptions. In this article, we present on an example the
use of multidimensional scaling, semantic differential method and preference
mapping for the subjective assessment of virtual products. These products,
which geometrical form is variable, are defined with a CAD model and are
proposed to the user with a spacemouse and stereoscopic glasses. Advantages and
limitations of such evaluation is next discussed..


title: Black hole analogues in braneworld scenario

abstract:
  We construct analogue black hole solutions in the braneworld scenario. The
quantum fluctuations of condensate gravitons propagating around a
$4+n$-dimensional gravitational potential are found yielding a metric similar
to higher dimensional Schwarzschild black hole line-element. Black hole
analogue solutions in Randall-Sundrum and Dvali-Gabadadze-Porrati brane world
models are also constructed. The properties of such black hole analogues are
discussed.


title: Realistic Rendering of Kinetostatic Indices of Mechanisms

abstract:
  The work presented in this paper is related to the use of a haptic device in
an environment of robotic simulation. Such device introduces a new approach to
feel and to understand the boundaries of the workspace of mechanisms as well as
its kinetostatic properties. Indeed, these concepts are abstract and thus often
difficult to understand for the end-users. To catch his attention, we propose
to amplify the problems of the mechanisms in order to help him to take the good
decisions.


title: Experimental demonstration of Shor's algorithm with quantum entanglement

abstract:
  Shor's powerful quantum algorithm for factoring represents a major challenge
in quantum computation and its full realization will have a large impact on
modern cryptography. Here we implement a compiled version of Shor's algorithm
in a photonic system using single photons and employing the non-linearity
induced by measurement. For the first time we demonstrate the core processes,
coherent control, and resultant entangled states that are required in a
full-scale implementation of Shor's algorithm. Demonstration of these processes
is a necessary step on the path towards a full implementation of Shor's
algorithm and scalable quantum computing. Our results highlight that the
performance of a quantum algorithm is not the same as performance of the
underlying quantum circuit, and stress the importance of developing techniques
for characterising quantum algorithms.


title: A New Concept of Modular Parallel Mechanism for Machining Applications

abstract:
  The subject of this paper is the design of a new concept of modular parallel
mechanisms for three, four or five-axis machining applications. Most parallel
mechanisms are designed for three- or six-axis machining applications. In the
last case, the position and the orientation of the tool are coupled and the
shape of the workspace is complex. The aim of this paper is to use a simple
parallel mechanism with two-degree-of-freedom (dof) for translation motions and
to add one or two legs to add one or two-dofs for rotation motions. The
kinematics and singular configurations are studied for each mechanism.


title: A Workspace based Classification of 3R Orthogonal Manipulators

abstract:
  A classification of a family of 3-revolute (3R) positioning manipulators is
established. This classification is based on the topology of their workspace.
The workspace is characterized in a half-cross section by the singular curves
of the manipulator. The workspace topology is defined by the number of cusps
and nodes that appear on these singular curves. The design parameters space is
shown to be partitioned into nine subspaces of distinct workspace topologies.
Each separating surface is given as an explicit expression in the
DH-parameters.


title:
Manifestations of fine features of the density of states in the
  transport properties of KOs2O6

abstract:
  We performed high-pressure transport measurements on high-quality single
crystals of KOs2O6, a beta-pyrochlore superconductor. While the resistivity at
high temperatures might approach saturation, there is no sign of saturation at
low temperatures, down to the superconducting phase. The anomalous resistivity
is accompanied by a nonmetallic behavior in the thermoelectric power (TEP) up
to temperatures of at least 700 K, which also exhibits a broad hump with a
maximum at 60 K. The pressure influences mostly the low-energy electronic
excitations. A simple band model based on enhanced density of states in a
narrow window around the Fermi energy (EF) explains the main features of this
unconventional behavior in the transport coefficients and its evolution under
pressure.


title:
Phonon and Magnetic Pairing Mechanisms in High-Temperature
  Superconductors in the Strong Correlation Mode

abstract:
  The t-t'-t''-J model of electrons interacting with three phonon modes
(breathing, apical breathing, and buckling) is considered. The wave-vector
dependence of the matrix elements of the electron-phonon interaction leads to
opposite contributions to the pairing potential with the d-symmetry: the
buckling mode facilitates electron pairing, while the breathing mode suppresses
it. As a result, the critical temperature of La{2 - x}Sr{x}CuO{4} that is
associated with the magnetic mechanism is lowered when phonons are taken into
account.


title: The geometry of bipartite qutrits including bound entanglement

abstract:
  We investigate the state space of bipartite qutrits. We construct an analog
to the "magic" tetrahedron for bipartite qubits--a magic simplex W. It is
formed by all convex combination of nine Bell states which are constructed
using the Weyl operators. Due to the high symmetry it is enough to consider
certain typical slices through W. Via optimal entanglement witnesses we find
regions of bound entangled states inside W.


title: Probing extra dimensions with higher dimensional black hole analogues?

abstract:
  We propose that extra dimensions might be detected with higher dimensional
analogues of black holes. The usual 4-dimensional acoustic(sonic)black hole
metric is extended to arbitrary dimensions. The absorption cross-section of
Hawking radiation on the brane and in the bulk are calculated in the
semiclassical approximation.


title: Long-range and selective coupler for superconducting flux qubits

abstract:
  We propose a qubit-qubit coupling scheme for superconducting flux quantum
bits (qubits), where a quantized Josephson junction resonator and microwave
irradiation are utilized. The junction is used as a tunable inductance
controlled by changing the bias current flowing through the junction, and thus
the circuit works as a tunable resonator. This enables us to make any qubits
interact with the resonator. Entanglement between two of many qubits whose
level splittings satisfy some conditions, is formed by microwave irradiation
causing a two-photon Rabi oscillation. Since the size of the resonator can be
as large as sub-millimeters and qubits interact with it via mutual inductance,
our scheme makes it possible to construct a quantum gate involving remote
qubits


title:
A Trickiness of the High-Temperature Limit for Number Density
  Correlation Functions in Classical Coulomb Fluids

abstract:
  The Debye-H\"uckel theory describes rigorously the thermal equilibrium of
classical Coulomb fluids in the high-temperature $\beta\to 0$ regime ($\beta$
denotes the inverse temperature). It is generally believed that the
Debye-H\"uckel theory and the systematic high-temperature expansion provide an
adequate description also in the region of small {\em strictly positive} values
of $\beta>0$. This hypothesis is tested in the present paper on a
two-dimensional Coulomb gas of pointlike $+/-$ unit charges interacting via a
logarithmic potential which is equivalent to an integrable sine-Gordon field
model. In particular, we apply a form factor method to obtain the exact
asymptotic large-distance behavior of particle correlation functions,
considered in the charge and number density combinations. We first determine
the general forms of the leading and subleading asymptotic terms at strictly
positive $\beta>0$ and then evaluate their high-temperature $\beta\to 0$ forms.
In the case of the {\em charge} correlation function, the leading asymptotic
term at a strictly positive $\beta>0$ is also the leading one in the
high-temperature $\beta\to 0$ regime. On the contrary, the $\beta\to 0$
behavior of the {\em number density} correlation function is accompanied by an
interference between the first two asymptotic terms. Consequently, the
large-distance behavior of this function exhibits a discontinuity when going
from strictly positive values of $\beta>0$ to the Debye-H\"uckel limit
$\beta\to 0$. This is the crucial conclusion of the paper: the large-distance
asymptotics and the high-temperature limit do not commute for the density
correlation function of the two-dimensional Coulomb gas.


title:
On the dense point and absolutely continuous spectrum for Hamiltonians
  with concentric $\delta$ shells

abstract:
  We consider Schr\"odinger operator in dimension $d\ge 2$ with a singular
interaction supported by an infinite family of concentric spheres, analogous to
a system studied by Hempel and coauthors for regular potentials. The essential
spectrum covers a halfline determined by the appropriate one-dimensional
comparison operator; it is dense pure point in the gaps of the latter. If the
interaction is radially periodic, there are absolutely continuous bands; in
contrast to the regular case the measure of the p.p. segments does not vanish
in the high-energy limit.

categories: math-ph cond-mat.mes-hall math.MP math.SP quant-ph


title:
Role of electronic correlations in the Fermi surface formation of
  Na$_x$CoO$_2$

abstract:
  Band structure of metallic sodium cobaltate Na$_x$CoO$_2$ ($x$=0.33, 0.48,
0.61 0.72) has been investigated by local density approximation+Hubbard $U$
(LDA+$U$) method and within Gutzwiller approximation for the Co-$t_{2g}$
manifold. Correlation effects being taken into account results in suppression
of the $e'_g$ hole pockets at the Fermi surface in agreement with recent
angle-resolved photo-emission spectroscopy (ARPES) experiments. In the
Gutzwiller approximation the bilayer splitting is significantly reduced due to
the correlation effects. The formation of high spin (HS) state in Co $d$-shell
was shown to be very improbable.


title:
Singularity Surfaces and Maximal Singularity-Free Boxes in the Joint
  Space of Planar 3-RPR Parallel Manipulators

abstract:
  In this paper, a method to compute joint space singularity surfaces of 3-RPR
planar parallel manipulators is first presented. Then, a procedure to determine
maximal joint space singularity-free boxes is introduced. Numerical examples
are given in order to illustrate graphically the results. This study is of high
interest for planning trajectories in the joint space of 3-RPR parallel
manipulators and for manipulators design as it may constitute a tool for
choosing appropriate joint limits and thus for sizing the link lengths of the
manipulator.


title: Kinematics analysis of the parallel module of the VERNE machine

abstract:
  The paper derives the inverse and forward kinematic equations of a spatial
three-degree-of-freedom parallel mechanism, which is the parallel module of a
hybrid serial-parallel 5-axis machine tool. This parallel mechanism consists of
a moving platform that is connected to a fixed base by three non-identical
legs. Each leg is made up of one prismatic and two pair spherical joint, which
are connected in a way that the combined effects of the three legs lead to an
over-constrained mechanism with complex motion. This motion is defined as a
simultaneous combination of rotation and translation.


title: Supertransvectants and symplectic geometry

abstract:
  We consider the $osp(1|2)$-invariant bilinear operations on weighted
densities on the supercircle $S^{1|1}$ called the supertransvectants. These
operations are analogues of the famous Gordan transvectants (or Rankin-Cohen
brackets). We prove that these operations coincide with the iterated Poisson
and ghost Poisson brackets on ${\mathbb R}^{2|1}$ and apply this result to
construct star-products involving the supertransvectants.


title:
Rapidly rotating spherical Couette flow in a dipolar magnetic field: an
  experimental study of the mean axisymmetric flow

abstract:
  In order to explore the magnetostrophic regime expected for planetary cores,
experiments have been conducted in a rotating sphere filled with liquid sodium,
with an imposed dipolar magnetic field (the DTS setup). The field is produced
by a permanent magnet enclosed in an inner sphere, which can rotate at a
separate rate, producing a spherical Couette flow. The flow properties are
investigated by measuring electric potentials on the outer sphere, the induced
magnetic field in the laboratory frame, and velocity profiles inside the liquid
sodium using ultrasonic Doppler velocimetry. The present article focuses on the
time-averaged axisymmetric part of the flow. The Doppler profiles show that the
angular velocity of the fluid is relatively uniform in most of the fluid shell,
but rises near the inner sphere, revealing the presence of a magnetic wind, and
gently drops towards the outer sphere. The transition from a magnetostrophic
flow near the inner sphere to a geostrophic flow near the outer sphere is
controlled by the local Elsasser number. For Rossby numbers up to order 1, the
observed velocity profiles all show a similar shape. Numerical simulations in
the linear regime are computed, and synthetic velocity profiles are compared
with the measured ones. In the geostrophic region, a torque-balance model
provides very good predictions. We find that the induced magnetic field varies
in a consistent fashion, and displays a peculiar peak in the counter-rotating
regime. This happens when the fluid rotation rate is almost equal and opposite
to the outer sphere rotation rate. The fluid is then almost at rest in the
laboratory frame, and the Proudman-Taylor constraint vanishes, enabling a
strong meridional flow. We suggest that dynamo action might be favored in such
a situation.


title: Diffraction : Recent Results and Implications for LHC

abstract:
  With the knowledge of diffractive parton densities extracted from HERA data,
we discuss the observation of exclusive events using the dijet mass fraction as
measured by the CDF collaboration at the Tevatron. In particular the impact of
the gluon density uncertainty is analysed. Some prospects are given for
diffractive physics at the LHC.


title: The Entropy Bound for Local Quantum Field Theory

abstract:
  We investigate the entropy bound for local quantum field theory in this
paper. Both the bosonic and fermionic fields confined to an asymptotically flat
spacetime are examined. By imposing the non-gravitational collapse condition,
we find both of them are limited by the same entropy bound $A^{3/4}$, where $A$
is the boundary area of the region where the quantum fields are contained in.
The gap between this entropy bound and the holographic entropy has been
verified.


title: Self diffusion of reversibly aggregating spheres

abstract:
  Reversible diffusion limited cluster aggregation of hard spheres with rigid
bonds was simulated and the self diffusion coefficient was determined for
equilibrated systems. The effect of increasing attraction strength was
determined for systems at different volume fractions and different interaction
ranges. It was found that the slowing down of the diffusion coefficient due to
crowding is decoupled from that due to cluster formation. The diffusion
coefficient could be calculated from the cluster size distribution and became
zero only at infinite attraction strength when permanent gels are formed. It is
concluded that so-called attractive glasses are not formed at finite
interaction strength.


title:
A Generalization of the Stillinger-Lovett Sum Rules for the
  Two-Dimensional Jellium

abstract:
  In the equilibrium statistical mechanics of classical Coulomb fluids, the
long-range tail of the Coulomb potential gives rise to the Stillinger-Lovett
sum rules for the charge correlation functions. For the jellium model of mobile
particles of charge $q$ immersed in a neutralizing background, the fixing of
one of the $q$-charges induces a screening cloud of the charge density whose
zeroth and second moments are determined just by the Stillinger-Lovett sum
rules. In this paper, we generalize these sum rules to the screening cloud
induced around a pointlike guest charge $Z q$ immersed in the bulk interior of
the 2D jellium with the coupling constant $\Gamma=\beta q^2$ ($\beta$ is the
inverse temperature), in the whole region of the thermodynamic stability of the
guest charge $Z>-2/\Gamma$. The derivation is based on a mapping technique of
the 2D jellium at the coupling $\Gamma$ = (even positive integer) onto a
discrete 1D anticommuting-field theory; we assume that the final results remain
valid for all real values of $\Gamma$ corresponding to the fluid regime. The
generalized sum rules reproduce for arbitrary coupling $\Gamma$ the standard
Z=1 and the trivial Z=0 results. They are also checked in the Debye-H\"uckel
limit $\Gamma\to 0$ and at the free-fermion point $\Gamma=2$. The generalized
second-moment sum rule provides some exact information about possible sign
oscillations of the induced charge density in space.


title: The AGN and Gas Disk in the Low Surface Brightness Galaxy PGC045080

abstract:
  We present radio observations and optical spectroscopy of the giant low
surface brightness (LSB) galaxy PGC 045080 (or 1300+0144). PGC 045080 is a
moderately distant galaxy having a highly inclined optical disk and massive HI
gas content. Radio continuum observations of the galaxy were carried out at 320
MHz, 610 MHz and 1.4 GHz. Continuum emission was detected and mapped in the
galaxy. The emission appears extended over the inner disk at all three
frequencies. At 1.4 GHz and 610 MHz it appears to have two distinct lobes. We
also did optical spectroscopy of the galaxy nucleus; the spectrum did not show
any strong emission lines associated with AGN activity but the presence of a
weak AGN cannot be ruled out. Furthermore, comparison of the H$\alpha$ flux and
radio continuum at 1.4 GHz suggests that a significant fraction of the emission
is non-thermal in nature. Hence we conclude that a weak or hidden AGN may be
present in PGC 045080. The extended radio emission represents lobes/jets from
the AGN. These observations show that although LSB galaxies are metal poor and
have very little star formation, their centers can host significant AGN
activity. We also mapped the HI gas disk and velocity field in PGC 045080. The
HI disk extends well beyond the optical disk and appears warped. In the HI
intensity maps, the disk appears distinctly lopsided. The velocity field is
disturbed on the lopsided side of the disk but is fairly uniform in the other
half. We derived the HI rotation curve for the galaxy from the velocity field.
The rotation curve has a flat rotation speed of ~ 190 km/s.


title:
Theory of Macroscopic Quantum Tunneling in High-T_c c-Axis Josephson
  Junctions

abstract:
  We study macroscopic quantum tunneling (MQT) in c-axis twist Josephson
junctions made of high-T_c superconductors in order to clarify the influence of
the anisotropic order parameter symmetry (OPS) on MQT. The dependence of the
MQT rate on the twist angle $\gamma$ about the c-axis is calculated by using
the functional integral and the bounce method. Due to the d-wave OPS, the
$\gamma$ dependence of standard deviation of the switching current distribution
and the crossover temperature from thermal activation to MQT are found to be
given by $\cos2\gamma$ and $\sqrt{\cos2\gamma}$, respectively. We also show
that a dissipative effect resulting from the nodal quasiparticle excitation on
MQT is negligibly small, which is consistent with recent MQT experiments using
Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8 + \delta}$ intrinsic junctions. These results
indicate that MQT in c-axis twist junctions becomes a useful experimental tool
for testing the OPS of high-T_c materials at low temperature, and suggest high
potential of such junctions for qubit applications.


title:
Effect of the tensor force in the exchange channel on the spin-orbit
  splitting in 23F in the Hartree-Fock framework

abstract:
  We study the spin-orbit splitting ($ls$-splitting) for the proton d-orbits in
23F in the Hartree-Fock framework with the tensor force in the exchange
channel. 23F has one more proton around the neutron-rich nucleus 22O. A recent
experiment indicates that the ls-splitting for the proton d-orbits in 23F is
reduced from that in 17F. Our calculation shows that the ls-splitting in 23F
becomes smaller by about a few MeV due to the tensor force. This effect comes
from the interaction between the valence proton and the occupied neutrons in
the 0d5/2 orbit through the tensor force and makes the ls-splitting in 23F
close to the experimental data.


title:
Every compact group arises as the outer automorphism group of a II_1
  factor

abstract:
  We show that any compact group can be realized as the outer automorphism
group of a factor of type II_1. This has been proved in the abelian case by
Ioana, Peterson and Popa applying Popa's deformation/rigidity techniques to
amalgamated free product von Neumann algebras. Our methods are a generalization
of theirs.


title:
Comment on ''Measurement of Effective Temperatures in an Aging Colloidal
  Glass''

abstract:
  We measure the fluctuations of the position of a silica bead trapped by an
optical tweezers during the aging of a Laponite suspension. We find that the
effective temperature is equal to the bath temperature.


title: Self-Dual Supergravity and Twistor Theory

abstract:
  By generalizing and extending some of the earlier results derived by Manin
and Merkulov, a twistor description is given of four-dimensional N-extended
(gauged) self-dual supergravity with and without cosmological constant.
Starting from the category of (4|4N)-dimensional complex superconformal
supermanifolds, the categories of (4|2N)-dimensional complex quaternionic,
quaternionic Kaehler and hyper-Kaehler right-chiral supermanifolds are
introduced and discussed. We then present a detailed twistor description of
these types of supermanifolds. In particular, we construct supertwistor spaces
associated with complex quaternionic right-chiral supermanifolds, and explain
what additional supertwistor data allows for giving those supermanifolds a
hyper-Kaehler structure. In this way, we obtain a supersymmetric generalization
of Penrose's nonlinear graviton construction. We furthermore give an
alternative formulation in terms of a supersymmetric extension of LeBrun's
Einstein bundle. This allows us to include the cases with nonvanishing
cosmological constant. We also discuss the bundle of local supertwistors and
address certain implications thereof. Finally, we comment on a real version of
the theory related to Euclidean signature.


title: Counting hyperelliptic curves that admit a Koblitz model

abstract:
  Let k be a finite field of odd characteristic. We find a closed formula for
the number of k-isomorphism classes of pointed, and non-pointed, hyperelliptic
curves of genus g over k, admitting a Koblitz model. These numbers are
expressed as a polynomial in the cardinality q of k, with integer coefficients
(for pointed curves) and rational coefficients (for non-pointed curves). The
coefficients depend on g and the set of divisors of q-1 and q+1. These formulas
show that the number of hyperelliptic curves of genus g suitable (in principle)
of cryptographic applications is asymptotically (1-e^{-1})2q^{2g-1}, and not
2q^{2g-1} as it was believed. The curves of genus g=2 and g=3 are more
resistant to the attacks to the DLP; for these values of g the number of curves
is respectively (91/72)q^3+O(q^2) and (3641/2880)q^5+O(q^4).


title: Local Distinguishability of Multipartite Unitary Operations

abstract:
  We show that any two different unitary operations acting on an arbitrary
multipartite quantum system can be perfectly distinguishable by local
operations and classical communication when a finite number of runs is allowed.
We then directly extend this result into the case when the number of unitary
operations to be discriminated is more than two. Intuitively, our result means
that the lost identity of a nonlocal (entangled) unitary operation can be
recovered locally, without any use of entanglement or joint quantum operations.


title: Force distributions and force chains in random stiff fiber networks

abstract:
  We study the elasticity of random stiff fiber networks. The elastic response
of the fibers is characterized by a central force stretching stiffness as well
as a bending stiffness that acts transverse to the fiber contour. Previous
studies have shown that this model displays an anomalous elastic regime where
the stretching mode is fully frozen out and the elastic energy is completely
dominated by the bending mode. We demonstrate by simulations and scaling
arguments that, in contrast to the bending dominated \emph{elastic energy}, the
equally important \emph{elastic forces} are to a large extent stretching
dominated. By characterizing these forces on microscopic, mesoscopic and
macroscopic scales we find two mechanisms of how forces are transmitted in the
network. While forces smaller than a threshold $F_c$ are effectively balanced
by a homogeneous background medium, forces larger than $F_c$ are found to be
heterogeneously distributed throughout the sample, giving rise to highly
localized force-chains known from granular media.


title: Dynamics of light propagation in spatiotemporal dielectric structures

abstract:
  Propagation, transmission and reflection properties of linearly polarized
plane waves and arbitrarily short electromagnetic pulses in one-dimensional
dispersionless dielectric media possessing an arbitrary space-time dependence
of the refractive index are studied by using a two-component, highly symmetric
version of Maxwell's equations. The use of any slow varying amplitude
approximation is avoided. Transfer matrices of sharp nonstationary interfaces
are calculated explicitly, together with the amplitudes of all secondary waves
produced in the scattering. Time-varying multilayer structures and
spatiotemporal lenses in various configurations are investigated analytically
and numerically in a unified approach. Several new effects are reported, such
as pulse compression, broadening and spectral manipulation of pulses by a
spatiotemporal lens, and the closure of the forbidden frequency gaps with the
subsequent opening of wavenumber bandgaps in a generalized Bragg reflector.


title:
The origin of the molecular emission around the southern hemisphere Re 4
  IRS - HH 188 region

abstract:
  We present SEST observations of the molecular environment ahead of the
southern Herbig-Haro object 188 (HH188), associated with the low-mass protostar
Re4 IRS. We have also used the SuperCosmos Halpha survey to search for Halpha
emission associated with the Re4 IRS - HH188 region. The aim of the present
work is to study the properties of the molecular gas and to better characterize
this southern star forming region. We mapped the HCO+ 3-2 and H13CO+ 1-0
emission around the YSO and took spectra of the CH3OH 2(0)-1(0)A+ and
2(-1)-1(-1)E and SO 6(5)-5(4) towards the central source. Column densities are
derived and different scenarios are considered to explain the origin of the
molecular emission. HCO+ arises from a relatively compact region around the
YSO; however, its peak emission is displaced to the south following the outflow
direction. Our chemical analysis indicates that a plausible scenario is that
most of the emission arises from the cold, illuminated dense gas ahead of the
HH188 object. We have also found that HH188, a high excitation object, seems to
be part of a parsec scale and highly collimated HH system. Re4 IRS is probably
a binary protostellar system, in the late Class 0 or Class I phase. One of the
protostars, invisible in the near-IR, seems to power the HH188 system.


title: Path Integral Methods in the Su-Schrieffer-Heeger Polaron Problem

abstract:
  I propose a path integral description of the Su-Schrieffer-Heeger
Hamiltonian, both in one and two dimensions, after mapping the real space model
onto the time scale. While the lattice degrees of freedom are classical
functions of time and are integrated out exactly, the electron particle paths
are treated quantum mechanically. The method accounts for the variable range of
the electronic hopping processes. The free energy of the system and its
temperature derivatives are computed by summing at any $T$ over the ensemble of
relevant particle paths which mainly contribute to the total partition
function. In the low $T$ regime, the {\it heat capacity over T} ratio shows un
upturn peculiar to a glass-like behavior. This feature is more sizeable in the
square lattice than in the linear chain as the overall hopping potential
contribution to the total action is larger in higher dimensionality. The
effects of the electron-phonon anharmonic interactions on the phonon subsystem
are studied by the path integral cumulant expansion method.