title:
Thermodynamics and bulk viscosity of approximate black hole duals to
  finite temperature quantum chromodynamics

abstract:
  We consider classes of translationally invariant black hole solutions whose
equations of state closely resemble that of QCD at zero chemical potential. We
use these backgrounds to compute the ratio zeta/s of bulk viscosity to entropy
density. For a class of black holes that exhibits a first order transition, we
observe a sharp rise in zeta/s near T_c. For constructions that exhibit a
smooth cross-over, like QCD does, the rise in zeta/s is more modest. We
conjecture that divergences in zeta/s for black hole horizons are related to
extrema of the entropy density as a function of temperature.


title: Where are the massive stars of the bar of NGC 1530 forming?

abstract:
  Aims: NGC 1530 has one of the strongest bars ever observed and recent star
formation sites are distributed across its bar. Our aim is to study the
photometric properties of the bar and its HII regions, to elucidate the
conditions under which HII regions form and their spatial relation to the
principal dynamical features of the bar. Methods: We obtained BVRKs and Halpha
photometry of the HII regions of the bar in NGC 1530. Broad-band integrated
colours and Halpha equivalent widths were carefully measured and analysed as a
function of position with respect to the main dust-lanes of the bar. Results:
We measured differences in the Halpha equivalent widths of the HII regions that
are located in the trailing and leading sides of the bar dust-lane. The
possible factors that could produce this difference, such as [NII]
contamination, Lyman-continuum-photon dust-extinction, escape of ionizing
radiation, metallicity, IMF and age, were carefully analysed. Age differences
were confirmed to be the most plausible explanation. This implies that HII
regions that are located further away from the bar dust-lane in its leading
side, downstream from the main bar dust-lane, are older than the rest by
~1.5-2.5 Myr. In addition, a clear spatial correlation has been found between:
location of HII regions, dust spurs on the trailing side of the bar dust-lane,
and the loci of maximum velocity gradients parallel to the bar major axis
(possibly tracing gas flow towards the main bar dust-lane). These results
support the hypothesis that massive stars are forming on the trailing side of
the bar dust-lane, and age as they cross the bar, on a timescale that is
compatible with the bar dynamics timescale.


title:
Scalar and spin-dependent relativistic effects on magnetic properties
  calculated with four-component methods: the nuclear magnetic resonance
  parameters of the lead halides

abstract:
  The results of calculations of nuclear magnetic resonance (NMR) parameters
for the lead halides is reported in this paper. The results are obtained by
using four-component methods. The use of the nonrelativistic L\'evy-Leblond
Hamiltonian along with the relativistic Dirac-Coulomb and spin-free ones allows
us to discriminate scalar and spin-dependent effects on the parameters. It is
found that the wide range of the lead NMR spectra and their large anisotropies
are, mainly, due to spin-dependent effects on the paramagnetic term. Among the
relativistic scalar corrections, the so-called spin-Zeeman kinetic-energy term
turns out to be dominant. The reduced spin-spin coupling constants become
proportional to the product of the atomic numbers of the coupled nuclei.


title: Nonhomeomorphic conjugates of connected Shimura varieties

abstract:
  We show that conjugation by an automorphism of the complex numbers (as an
abstract field) may change the topological fundamental group of a locally
symmetric variety over C. As a consequence, we obtain a large class of
algebraic varieties defined over number fields with the property that different
embeddings of the number field into C give complex varieties with nonisomorphic
fundamental groups.


title: The Flavor of the Composite Pseudo-Goldstone Higgs

abstract:
  We study the flavor structure of 5D warped models that provide a dual
description of a composite pseudo-Goldstone Higgs. We first carefully
re-examine the flavor constraints on the mass scale of new physics in the
standard Randall-Sundrum-type scenarios, and find that the KK gluon mass should
generically be heavier than about 21 TeV. We then compare the flavor structure
of the composite Higgs models to those in the RS model. We find new
contributions to flavor violation, which while still are suppressed by the
RS-GIM mechanism, will enhance the amplitudes of flavor violations. In
particular, there is a kinetic mixing term among the SM fields which (although
parametrically not enhanced) will make the flavor bounds even more stringent
than in RS. This together with the fact that in the pseudo-Goldstone scenario
Yukawa couplings are set by a gauge coupling implies the KK gluon mass to be at
least about 33 TeV. For both the RS and the composite Higgs models the flavor
bounds could be stronger or weaker depending on the assumption on the value of
the gluon boundary kinetic term. These strong bounds seem to imply that the
fully anarchic approach to flavor in warped extra dimensions is implausible,
and there have to be at least some partial flavor symmetries appearing that
eliminate part of the sources for flavor violation. We also present complete
expressions for the radiatively generated Higgs potential of various 5D
implementations of the composite Higgs model, and comment on the 1-5 percent
level tuning needed in the top sector to achieve a phenomenologically
acceptable vacuum state.


title:
Chandra Observations of the Cl1604 Supercluster at z=0.9: Evidence for
  an Overdensity of Active Galactic Nuclei

abstract:
  We present the results of Chandra observations of the Cl1604 supercluster at
z~0.9. The system is the largest structure mapped at redshifts approaching
unity, containing at least eight spectroscopically confirmed galaxy clusters
and groups. Using two 50-ksec ACIS-I pointings we examine both the X-ray point
source population and the diffuse emission from individual clusters in the
system. We find a 2.5\sigma excess of point sources detected in the hard band
(2-10 keV) relative to the number of sources found in blank fields observed by
Chandra. No such excess is observed in the soft band (0.5-2 keV). The hard-band
source density is 1.47 times greater than that of a blank field, in agreement
with the previously reported correlation between overdensity amplitude and
cluster redshift. Using a maximum likelihood technique we have matched 112 of
the 161 detected X-ray point sources to optical counterparts and found 15
sources that are associated with the supercluster. All 15 sources have
rest-frame luminosities consistent with emission from active galactic nuclei
(AGN). We find that the supercluster AGN largely avoid the densest regions of
the system and are instead distributed on the outskirts of massive clusters or
within poorer clusters and groups. We have also detected diffuse emission from
two of the eight clusters and groups in the system, clusters Cl1604+4304 and
Cl1604+4314. The systems have bolometric luminosities of 1.43x10^44 and
8.20x10^43 h70^-2 erg s^-1 and gas temperatures of 3.50 (+1.82-1.08) and 1.64
(+0.65-0.45) keV, respectively. Using updated velocity dispersions, we compare
the properties of these systems to the cluster scaling relations followed by
other X-ray and optically selected galaxy clusters at high redshift.


title: The Hausdorff dimension of self-affine Sierpinski sponges

abstract:
  We compute the Hausdorff dimension of limit sets generated by 3-dimensional
self-affine mappings with diagonal matrices of the form A_{ijk}=Diag(a_{ijk},
b_{ij}, c_{i}), where 0<a_{ijk}\le b_{ij}\le c_i<1. By doing so we show that
the variational principle for the dimension holds for this class.


title: Central charges of N=2 superconformal field theories in four dimensions

abstract:
  We present a general method for computing the central charges a and c of N=2
superconformal field theories corresponding to singular points in the moduli
space of N=2 gauge theories. Our method relates a and c to the U(1)_R anomalies
of the topologically twisted gauge theory. We evaluate these anomalies by
studying the holomorphic dependence of the path integral measure on the moduli.
We calculate a and c for superconformal points in a variety of gauge theories,
including N=4 SU(N), N=2 pure SU(N) Yang-Mills, and USp(2N) with 1 massless
antisymmetric and 4 massive fundamental hypermultiplets. In the latter case, we
reproduce the conformal and flavor central charges previously calculated using
the gravity duals of these gauge theories. For any SCFT in the class under
consideration, we derive a previously conjectured expression for 2a-c in terms
of the sum of the dimensions of operators parameterizing the Coulomb branch.
Finally, we prove that the ratio a/c is bounded above by 5/4 and below by 1/2.


title:
Limits of the Plane Wave Approximation in the Measurement of Molecular
  Properties

abstract:
  Rescattering electrons offer great potential as probes of molecular
properties on ultrafast timescales. The most famous example is molecular
tomography, in which high harmonic spectra of oriented molecules are mapped to
``tomographic images'' of the relevant molecular orbitals. The accuracy of such
reconstructions may be greatly affected by the distortion of scattering
wavefunctions from their asymptotic forms due to interactions with the parent
ion. We investigate the validity of the commonly used plane wave approximation
in molecular tomography, showing how such distortions affect the resulting
orbital reconstructions.


title:
The Afterglows of Swift-era Gamma-Ray Bursts II.: Type I GRB versus Type
  II GRB Optical Afterglows

abstract:
  We use a large sample of GRB afterglow and prompt-emission data (adding
further GRB afterglow observations in this work) to compare the optical
afterglows (or the lack thereof) of Type I GRBs with those of Type II GRBs. In
comparison to the afterglows of Type II GRBs, we find that those of Type I GRBs
have a lower average luminosity and show an intrinsic spread of luminosities at
least as wide. From late and deep upper limits on the optical transients, we
establish limits on the maximum optical luminosity of any associated supernova,
confirming older works and adding new results. We use deep upper limits on Type
I GRB optical afterglows to constrain the parameter space of possible mini-SN
emission associated with a compact-object merger. Using the prompt emission
data, we search for correlations between the parameters of the prompt emission
and the late optical afterglow luminosities. We find tentative correlations
between the bolometric isotropic energy release and the optical afterglow
luminosity at a fixed time after trigger (positive), and between the host
offset and the luminosity (negative), but no significant correlation between
the isotropic energy release and the duration of the GRBs. We also discuss
three anomalous GRBs, GRB 060505, GRB 060614, and GRB 060121, in the light of
their optical afterglow luminosities. (Abridged)


title: Quantum Hall States at $\nu=\frac{2}{k+2}$

abstract:
  We study the $\nu=\frac{2}{k+2}$ quantum Hall states which are particle-hole
conjugates of the $\nu=\frac{k}{k+2}$ Read-Rezayi states. We find that
equilibration between the different modes at the edge of such a state leads to
an emergent SU(2)$_k$ algebra in the counter-propagating neutral sector. Heat
flow along the edges of these states will be in the opposite direction of
charge flow. In the $k=3$ case, which may be relevant to $\nu=2+{2/5}$, the
thermal Hall conductance and the exponents associated with quasiparticle and
electron tunneling distinguish this state from competing states such as the
hierarchy/Jain state.


title: Few-electron semiconductor quantum dots with Gaussian confinement

abstract:
  We have performed Hartree-Fock calculations of electronic structure of N \le
10 electrons in a quantum dot modeled with a confining Gaussian potential well.
We discuss the conditions for the stability of N bound electrons in the system.
We show that the most relevant parameter determining the number of bound
electrons is $V_0 R^2$. Such a property arises from widely valid scaling
properties of the con ning potential. Gaussian Quantum dots having N = 2, 5 and
8 electrons are particularly stable in agreement with Hund rule. The shell
structure becomes less and less noticeable as the well radius increases.


title:
A modification of Einstein-Schrodinger theory that contains
  Einstein-Maxwell-Yang-Mills theory

abstract:
  The Lambda-renormalized Einstein-Schrodinger theory is a modification of the
original Einstein-Schrodinger theory in which a cosmological constant term is
added to the Lagrangian, and it has been shown to closely approximate
Einstein-Maxwell theory. Here we generalize this theory to non-Abelian fields
by letting the fields be composed of dxd Hermitian matrices. The resulting
theory incorporates the U(1) and SU(d) gauge terms of
Einstein-Maxwell-Yang-Mills theory, and is invariant under U(1) and SU(d) gauge
transformations. The special case where symmetric fields are multiples of the
identity matrix closely approximates Einstein-Maxwell-Yang-Mills theory in that
the extra terms in the field equations are 10^-13 of the usual terms for
worst-case fields accessible to measurement. The theory contains a symmetric
metric and Hermitian vector potential, and is easily coupled to the additional
fields of Weinberg-Salam theory or flipped SU(5) GUT theory. We also consider
the case where symmetric fields have small traceless parts, and show how this
suggests a possible dark matter candidate.


title:
On the spectral theory and dispersive estimates for a discrete
  Schr\"{o}dinger equation in one dimension

abstract:
  Based on the recent work \cite{KKK} for compact potentials, we develop the
spectral theory for the one-dimensional discrete Schr\"odinger operator $$ H
\phi = (-\De + V)\phi=-(\phi_{n+1} + \phi_{n-1} - 2 \phi_n) + V_n \phi_n. $$ We
show that under appropriate decay conditions on the general potential (and a
non-resonance condition at the spectral edges), the spectrum of $H$ consists of
finitely many eigenvalues of finite multiplicities and the essential
(absolutely continuous) spectrum, while the resolvent satisfies the limiting
absorption principle and the Puiseux expansions near the edges. These
properties imply the dispersive estimates $$ \|e^{i t H} P_{\rm
a.c.}(H)\|_{l^2_{\sigma} \to l^2_{-\sigma}} \lesssim t^{-3/2} $$ for any fixed
$\sigma > {5/2}$ and any $t > 0$, where $P_{\rm a.c.}(H)$ denotes the spectral
projection to the absolutely continuous spectrum of $H$. In addition, based on
the scattering theory for the discrete Jost solutions and the previous results
in \cite{SK}, we find new dispersive estimates $$ \|e^{i t H} P_{\rm a.c.}(H)
\|_{l^1\to l^\infty}\lesssim t^{-1/3}. $$ These estimates are sharp for the
discrete Schr\"{o}dinger operators even for $V = 0$.


title: Multiscale Edge Detection in the Corona

abstract:
  Coronal Mass Ejections (CMEs) are challenging objects to detect using
automated techniques, due to their high velocity and diffuse, irregular
morphology. A necessary step to automating the detection process is to first
remove the subjectivity introduced by the observer used in the current,
standard, CME detection and tracking method. Here we describe and demonstrate a
multiscale edge detection technique that addresses this step and could serve as
one part of an automated CME detection system. This method provides a way to
objectively define a CME front with associated error estimates. These fronts
can then be used to extract CME morphology and kinematics. We apply this
technique to a CME observed on 18 April 2000 by the Large Angle Solar
COronagraph experiment (LASCO) C2/C3 and a CME observed on 21 April 2002 by
LASCO C2/C3 and the Transition Region and Coronal Explorer (TRACE). For the two
examples in this work, the heights determined by the standard manual method are
larger than those determined with the multiscale method by approximately 10%
using LASCO data and approximately 20% using TRACE data.


title:
A calibration of the relation between the abundance of close galaxy
  pairs and the rate of galaxy mergers

abstract:
  Estimates of galaxy merger rates based on counts of close pairs typically
assume that most of the observed systems will merge within a few hundred Myr
(for projected pair separations <25 kpc/h). Here we investigate these
assumptions using virtual galaxy catalogues derived from the Millennium
Simulation, a very large N-body simulation of structure formation in the
concordance LCDM cosmology. These catalogues have been shown to be at least
roughly consistent with a wide range of properties of the observed galaxy
population at both low and high redshift. Here we show that they also predict
close pair abundances at low redshift which agree with those observed. They
thus embed a realistic and realistically evolving galaxy population within the
standard structure formation paradigm, and so are well-suited to calibrate the
relation between close galaxy pairs and mergers. We show that observational
methods, when applied to our mock galaxy surveys, do indeed identify pairs
which are physically close and due to merge. The sample-averaged merging time
depends only weakly on the stellar mass and redshift of the pair. At z<2 this
time-scale is T ~ T0 r25 M*^-0.3, where r25 is the maximum projected separation
of the pair sample in units of 25 kpc/h, M* is the typical stellar mass of the
pairs in units of 3x10^10 Msol/h, and the coefficient T0 is 1.1 Gyr for samples
selected to have line-of-sight velocity difference smaller than 300 km/s and
1.6 Gyr for samples where this velocity difference is effectively
unconstrained. These timescales increase slightly with redshift and are longer
than assumed in most observational studies, implying that merger rates have
typically been overestimated.


title:
Primary gas thermometry by means of laser-absorption spectroscopy:
  Determination of the Boltzmann constant

abstract:
  We report on a new optical implementation of primary gas thermometry based on
laser absorption spectrometry in the near infrared. The method consists in
retrieving the Doppler broadening from highly accurate observations of the line
shape of the R(12) $\nu_{1} + 2 \nu_{2}^{\phantom{1}0} + \nu_{3}$ transition in
CO$_{2}$ gas at thermodynamic equilibrium. Doppler width measurements as a
function of gas temperature, ranging between the triple point of water and the
gallium melting point, allowed for a spectroscopic determination of the
Boltzmann constant with a relative accuracy of $\sim1.6\times10^{-4}$.


title:
Colloid-polymer mixtures in random porous media: Finite size scaling and
  connected versus disconnected susceptibilities

abstract:
  As a generic model for liquid-vapour type transitions in random porous media,
the Asakura-Oosawa model for colloid-polymer mixtures is studied in a matrix of
quenched spheres using extensive Monte Carlo (MC) simulations. Since such
systems at criticality, as well as in the two-phase region, exhibit lack of
self-averaging, the analysis of MC data via finite size scaling requires
special care. After presenting the necessary theoretical background and the
resulting subtleties of finite size scaling in random-field Ising-type systems,
we present data on the order parameter distribution (and its moments) as a
function of colloid and polymer fugacities for a broad range of system sizes,
and for many (thousands) realizations of the porous medium. Special attention
is paid to the connected and disconnected susceptibilities, and their
respective critical behavior. We show that both susceptibilities diverge at the
critical point, and we demonstrate that this is compatible with the predicted
scenario of random-field Ising universality.


title: Fractal Boundaries of Complex Networks

abstract:
  We introduce the concept of boundaries of a complex network as the set of
nodes at distance larger than the mean distance from a given node in the
network. We study the statistical properties of the boundaries nodes of complex
networks. We find that for both Erd\"{o}s-R\'{e}nyi and scale-free model
networks, as well as for several real networks, the boundaries have fractal
properties. In particular, the number of boundaries nodes {\it B} follows a
power-law probability density function which scales as $B^{-2}$. The clusters
formed by the boundary nodes are fractals with a fractal dimension $d_{f}
\approx 2$. We present analytical and numerical evidence supporting these
results for a broad class of networks. Our findings imply potential
applications for epidemic spreading.

categories: math-ph cond-mat.dis-nn cond-mat.stat-mech math.MP physics.data-an physics.soc-ph


title:
Quantum systems under the influence of external conditions: fluctuations
  and decoherence

abstract:
  In this Thesis we study the quantum to classical transition process in the
context of quantum mechanics and quantum field theory. We shall analyze the
effects that general environments, namely ohmic and non-ohmic, at zero and high
temperature induce over a quantum Brownian particle. We state that the
evolution of the system can be summarized in terms of two main environmental
induced physical phenomena: decoherence and energy activation. In this Thesis,
we shall show that the latter is a post-decoherence phenomenon. As the energy
is an observable, the excitation process can be consider a direct indicator of
the system-environment entanglement particularly useful at zero temperature.
  From other point of view, we shall study different attempts to show the
decoherence process in double-slit-like experiments both for charged particles
(electrons) and for neutral particles with permanent dipole moments. In this
context, we shall show that the interaction between the particles and
time-dependent fields induces a time-varying Aharonov phase. In this context,
we shall apply our results to a real matter wave interferometry experiment. We
shall also show under which general conditions the geometry phase of a quantum
open system can be observed.Finally, we shall study the decoherence process
during a quantum phase transition. In this framework, we shall show that it can
be phrased easily in terms of the decoherence functional, without having to use
the master equation. To demonstrate this, we shall consider the decohering
effects due to the displacement of domain boundaries, with implications for the
displacement of defects, in general. We shall see that decoherence arises so
quickly in this event, that it is negligible in comparison to decoherence due
to field fluctuations in the way defined in previous papers.


title: A Security Protocol for Multi-User Authentication

abstract:
  In this note we propose an encryption communication protocol which also
provides database security. For the encryption of the data communication we use
a transformation similar to the Cubic Public-key transformation. This method
represents a many-to-one mapping which increases the complexity for any brute
force attack. Some interesting properties of the transformation are also
included which are basic in the authentication protocol.


title: Scalability of quantum computation with addressable optical lattices

abstract:
  We make a detailed analysis of error mechanisms, gate fidelity, and
scalability of proposals for quantum computation with neutral atoms in
addressable (large lattice constant) optical lattices. We have identified
possible limits to the size of quantum computations, arising in 3D optical
lattices from current limitations on the ability to perform single qubit gates
in parallel and in 2D lattices from constraints on laser power. Our results
suggest that 3D arrays as large as 100 x 100 x 100 sites (i.e., $\sim 10^6$
qubits) may be achievable, provided two-qubit gates can be performed with
sufficiently high precision and degree of parallelizability. Parallelizability
of long range interaction-based two-qubit gates is qualitatively compared to
that of collisional gates. Different methods of performing single qubit gates
are compared, and a lower bound of $1 \times 10^{-5}$ is determined on the
error rate for the error mechanisms affecting $^{133}$Cs in a blue-detuned
lattice with Raman transition-based single qubit gates, given reasonable limits
on experimental parameters.


title:
Viscous Decoupling Transitions for Individually Dragged Particles in
  Systems with Quenched Disorder

abstract:
  We show that when an individual particle is dragged through an assembly of
other particles in the presence of quenched disorder, a viscous decoupling
transition occurs between the dragged particle and the surrounding particles
which is controlled by the quenched disorder. A counterintuitive consequence of
this transition is that the velocity of the dragged particle can be increased
by increasing the strength or density of the quenched disorder. The decoupling
transition can also occur when the external drive on the dragged particle is
increased, and is observable as a clear signature in the velocity-force
response.


title:
Epitaxial checkerboard arrangement of nanorods in ZnMnGaO4 films studied
  by x-ray diffraction

abstract:
  The intriguing nano-structural properties of a ZnMnGaO4 film epitaxially
grown on MgO (001) substrate have been investigated using synchrotron
radiation-based x-ray diffraction. The ZnMnGaO4 film consisted of a
self-assembled checkerboard (CB) structure with perfectly aligned and regularly
spaced vertical nanorods. The lattice parameters of the orthorhombic and
rotated tetragonal phases of the CB structure were analyzed using H-K, H-L, and
K-L cross sections of the reciprocal space maps measured around various
symmetric and asymmetric reflections of the spinel structure. We demonstrate
that the symmetry of atomic displacements at the phases boundaries provides the
means for coherent coexistence of two domains types within the volume of the
film.


title: Schemes for Deterministic Polynomial Factoring

abstract:
  In this work we relate the deterministic complexity of factoring polynomials
(over finite fields) to certain combinatorial objects we call m-schemes. We
extend the known conditional deterministic subexponential time polynomial
factoring algorithm for finite fields to get an underlying m-scheme. We
demonstrate how the properties of m-schemes relate to improvements in the
deterministic complexity of factoring polynomials over finite fields assuming
the generalized Riemann Hypothesis (GRH). In particular, we give the first
deterministic polynomial time algorithm (assuming GRH) to find a nontrivial
factor of a polynomial of prime degree n where (n-1) is a smooth number.


title: Dissipation and criticality in the lowest Landau level of graphene

abstract:
  The lowest Landau level of graphene is studied numerically by considering a
tight-binding Hamiltonian with disorder. The Hall conductance
$\sigma_\mathrm{xy}$ and the longitudinal conductance $\sigma_\mathrm{xx}$ are
computed. We demonstrate that bond disorder can produce a plateau-like feature
centered at $\nu=0$, while the longitudinal conductance is nonzero in the same
region, reflecting a band of extended states between $\pm E_{c}$, whose
magnitude depends on the disorder strength. The critical exponent corresponding
to the localization length at the edges of this band is found to be $2.47\pm
0.04$. When both bond disorder and a finite mass term exist the localization
length exponent varies continuously between $\sim 1.0$ and $\sim 7/3$.


title:
Determining the WIMP mass using the complementarity between direct and
  indirect searches and the ILC

abstract:
  We study the possibility of identifying dark matter properties from
XENON-like 100 kg experiments and the GLAST satellite mission. We show that
whereas direct detection experiments will probe efficiently light WIMPs, given
a positive detection (at the 10% level for $m_{\chi} \lesssim 50$ GeV), GLAST
will be able to confirm and even increase the precision in the case of a NFW
profile, for a WIMP-nucleon cross-section $\sigma_{\chi-p} \lesssim 10^{-8}$
pb. We also predict the rate of production of a WIMP in the next generation of
colliders (ILC), and compare their sensitivity to the WIMP mass with the XENON
and GLAST projects.


title:
Comment on "15O(alpha,gamma)19Ne Breakout Reaction and Impact on X-Ray
  Bursts"

abstract:
  A recently published letter reports a measurement of alpha decay from states
in 19Ne at excitation energies below 4.5 MeV. The measured alpha decay
branching ratios B_alpha are used to calculate the astrophysical rate of the
15O(alpha,gamma)19Ne reaction and to draw conclusions regarding the transition
between steady state and unstable nuclear burning on accreting neutron stars.
Here I show that the calculated astrophysical reaction rate is based on an
unreliable value of B_alpha for the 4.03 MeV state and point out a serious
internal inconsistency in the letter's treatment of low statistics alpha decay
measurements.


title:
Extremal transmission and beating effect of acoustic wave in
  two-dimensional sonic crystal

abstract:
  The extremal transmission of acoustic wave near the Dirac point in
two-dimensional (2D) sonic crystal (SC), being inversely proportional to the
thickness of sample, has been demonstrated experimentally for the first time.
Some unusual beating effects have been observed experimentally when the
acoustic pulse transport through the 2D SC slabs. Such phenomena are completely
different from the oscillations of the wave in a slab or cavity originating
from the interface reflection or Fabry-Perot effect. They can be regarded as
acoustic analogue to Zitterbewegung of relativistic electron. The physical
origination for the phenomenon has been analyzed.


title: GRB afterglows in the ELT era

abstract:
  This is a very short conference proceeding based on a poster shown at the ESO
workshop "Science with the VLT in the ELT Era". For more information, see "The
Afterglows of Swift-era Gamma-Ray Bursts. I. Comparing pre-Swift and Swift era
Long/Soft (Type II) GRB Optical Afterglows" (arXiv:0712.2186) as well as "The
Afterglows of Swift-era Gamma-Ray Bursts. II. Short/Hard (Type I) vs. Long/Soft
(Type II) Optical Afterglows" (arXiv:0804.1959)


title: Afterglows of Gamma-Ray Bursts: Short vs. Long GRBs

abstract:
  We compiled a large sample of Swift-era photometric data on long (Type II)
and short (Type I) GRB afterglows. We compare the luminosity and energetics of
the different samples to each other and to the afterglows of the pre-Swift era.
Here, we present the first results of these studies.


title: Various considerations on hypergeometric series

abstract:
  E661 in the Enestrom index. This was originally published as "Variae
considerationes circa series hypergeometricas" (1776).
  In this paper Euler is looking at the asymptotic behavior of infinite
products that are similar to the Gamma function. He looks at the relations
between some infinite products and integrals. He takes the logarithm of these
infinite products, and expands these using the Euler-Maclaurin summation
formula.
  In section 14, Euler seems to be rederiving some of the results he already
proved in the paper. However I do not see how these derivations are different.
If any readers think they understand please I would appreciate it if you could
email me.
  I am presently examining Euler's work on analytic number theory. The two main
topics I want to understand are the analytic continuation of analytic functions
and the connection to divergent series, and the asymptotic behavior of the
Gamma function.


title: Linear Time Recognition Algorithms for Topological Invariants in 3D

abstract:
  In this paper, we design linear time algorithms to recognize and determine
topological invariants such as the genus and homology groups in 3D. These
properties can be used to identify patterns in 3D image recognition. This has
tremendous amount of applications in 3D medical image analysis. Our method is
based on cubical images with direct adjacency, also called (6,26)-connectivity
images in discrete geometry. According to the fact that there are only six
types of local surface points in 3D and a discrete version of the well-known
Gauss-Bonnett Theorem in differential geometry, we first determine the genus of
a closed 2D-connected component (a closed digital surface). Then, we use
Alexander duality to obtain the homology groups of a 3D object in 3D space.


title:
The character tables of centralizers in Weyl Groups of $E_6$, $E_7$,
  $F_4$, $G_2$

abstract:
  To classify the finite dimensional pointed Hopf algebras with Weyl group $G$
of $E_6$, $E_7$, $F_4$, $G_2$, we obtain the representatives of conjugacy
classes of $G$ and all character tables of centralizers of these
representatives by means of software GAP.


title: ZPF, Zitterbewegung and Inertial Mass

abstract:
  In this paper, we argue that the background Zero Point Field, induces an
oscillatory motion which we identify with zitterbewegung. We deduce that this
is the origin of inertial mass


title: Emulsion sheet doublets as interface trackers for the OPERA experiment

abstract:
  New methods for efficient and unambiguous interconnection between electronic
counters and target units based on nuclear photographic emulsion films have
been developed. The application to the OPERA experiment, that aims at detecting
oscillations between mu neutrino and tau neutrino in the CNGS neutrino beam, is
reported in this paper. In order to reduce background due to latent tracks
collected before installation in the detector, on-site large-scale treatments
of the emulsions ("refreshing") have been applied. Changeable Sheet (CSd)
packages, each made of a doublet of emulsion films, have been designed,
assembled and coupled to the OPERA target units ("ECC bricks"). A device has
been built to print X-ray spots for accurate interconnection both within the
CSd and between the CSd and the related ECC brick. Sample emulsion films have
been extensively scanned with state-of-the-art automated optical microscopes.
Efficient track-matching and powerful background rejection have been achieved
in tests with electronically tagged penetrating muons. Further improvement of
in-doublet film alignment was obtained by matching the pattern of low-energy
electron tracks. The commissioning of the overall OPERA alignment procedure is
in progress.


title:
Evolution from a molecular Rydberg gas to an ultracold plasma in a
  seeded supersonic expansion of NO

abstract:
  We report the spontaneous formation of a plasma from a gas of cold Rydberg
molecules. Double-resonant laser excitation promotes nitric oxide, cooled to 1
K in a seeded supersonic molecular beam, to single Rydberg states extending as
deep as 80 cm$^{-1}$ below the lowest ionization threshold. The density of
excited molecules in the illuminated volume is as high as 1 x 10$^{13}$
cm$^{-3}$. This population evolves to produce prompt free electrons and a
durable cold plasma of electrons and intact NO$^{+}$ ions.


title:
Nonlinear Dynamics of Gravity Wave Driven Flows in the Solar Radiative
  Interior

abstract:
  We present results of nonlinear numerical simulations of gravity wave driven
shear flow oscillations in the equatorial plane of the solar radiative
interior. These results show that many of the assumptions of quasi-linear
theory are not valid. When only two waves are forced (prograde and retrograde)
oscillatory mean flow is maintained; but critical layers often form and are
dynamically important. When a spectrum of waves is forced, the non-linear
wave-wave interactions are dynamically important, often acting to decrease the
maintenance of a mean flow. The (in)coherence of such wave-wave interactions
must be taken into account when describing wave driven mean flows.


title: Particle creation in the presence of a warped extra dimension

abstract:
  Particle creation in spacetimes with a warped extra dimension is studied. In
particular, we investigate the dynamics of a conformally coupled, massless
scalar field in a five dimensional warped geometry where the induced metric on
the 3--branes is that of a spatially flat cosmological model. We look at
situations where the scale of the extra dimension is assumed (i) to be time
independent or (ii) to have specific functional forms for time dependence. The
warp factor is chosen to be that of the Randall--Sundrum model. With particular
choices for the functional form of the scale factor (and also the function
characterising the time evolution of the extra dimension) we obtain the ${|
\beta_k|}^2$, the particle number and energy densities after solving (wherever
possible, analytically but, otherwise, numerically) the conformal scalar field
equations. The behaviour of these quantities for the massless and massive
Kaluza--Klein modes are examined. Our results show the effect of a warped extra
dimension on particle creation and illustrate how the nature of particle
production on the brane depends on the nature of warping, type of cosmological
evolution as well as the temporal evolution of the extra dimension.


title:
Secular variations in the solar corona shape according to observations
  during a solar activity minimum epoch

abstract:
  Analysis of the solar corona structure during the periods of minimum solar
activity from 1867 till 2006 has been carried out. A new flattening index for
the large coronal streamers has been proposed. It has been shown that the index
has been smoothly changing during the last 140 years. The minimal value of the
index occurred during activity cycles 17--19; this was the period when the
solar corona most of all corresponded to the dipole configuration of the global
magnetic field of the Sun. At the beginning of the 20th and the 21st centuries,
the corona structure corresponded to the quadrupole configuration. The reasons
for the variations in the solar corona structure and its relation to
geomagnetic activity are discussed.


title: Stein--Sahi complementary series and their degenerations

abstract:
  The aim of the paper is an introduction to Stein--Sahi complementary series,
holomorphic series, and 'unipotent representations'. We also discuss some open
problems related to these objects. For the sake of simplicity, we consider only
the groups U(n,n).


title:
Ground-state properties of interacting two-component Bose gases in a
  one-dimensional harmonic trap

abstract:
  We study ground-state properties of interacting two-component boson gases in
a one-dimensional harmonic trap by using the exact numerical diagonalization
method. Based on numerical solutions of many-body Hamiltonians, we calculate
the ground-state density distributions in the whole interaction regime for
different atomic number ratio, intra- and inter-atomic interactions. For the
case with equal intra- and inter-atomic interactions, our results clearly
display the evolution of density distributions from a Bose condensate
distribution to a Fermi-like distribution with the increase of the repulsive
interaction. Particularly, we compare our result in the strong interaction
regime to the exact result in the infinitely repulsive limit which can be
obtained by a generalized Bose-Fermi mapping. We also discuss the general case
with different intra- and inter-atomic interactions and show the rich
configurations of the density profiles.


title:
Structural, magnetic and mechanical properties of 5 $\mu$m thick SmCo
  films for use in Micro-Electro-Mechanical-Systems

abstract:
  5$\mu$m thick SmCo films were deposited onto Si substrates using triode
sputtering. A study of the influence of deposition temperature (Tdep <= 600
degrees C) on the structural, magnetic and mechanical properties has shown that
optimum properties (highest degree of in-plane texture, maximum in-plane
coercivity and remanence (1.3 and 0.8 T, respectively), no film peel-off) are
achieved for films deposited at the relatively low temperature of 350 degrees
C. This temperature is compatible with film integration into
Micro-Electro-Mechanical-Systems (MEMS). The deposition rate was increased from
3.6 to 18 $\mu$m/h by increasing the surface area of the target from 7 to 81
cm2. Mechanically stable films could be prepared by deposition onto
pre-patterned films or deposition through holes in a mask.


title: Searches for the Most Metal-Poor Candidates from SDSS and SEGUE

abstract:
  We report on efforts to identify large samples of very and extremely
metal-poor stars based on medium-resolution spectroscopy and ugriz photometry
obtained during the course of the Sloan Digital Sky Survey (SDSS), and its
extension, SDSS-II, which includes the program SEGUE: Sloan Extension for
Galactic Understanding and Exploration. To date, over 8000 stars with [Fe/H] <=
-2.0 and effective temperatures in the range 4500K < T_eff < 7000K have been
found, with the expected numbers in this temperature range to be well over
10,000 once SEGUE is completed. The numbers roughly double when one includes
warmer blue stragglers and Blue Horizontal-Branch (BHB) stars in these counts.
We show the observed low-metallicity tails of the Metallicity Distribution
Functions for the cooler SDSS/SEGUE stars obtained thus far. We also comment on
the confirmation of an inner/outer halo dichotomy in the Milky Way, and on how
this realization may be used to direct searches for even more metal-poor stars
in the near future.


title: Supersymmetric and nonsupersymmetric perturbations to KT

abstract:
  We studied the supersymmetric and non-supersymmetric perturbations to
cascading gauge theory. In particular we use KT background and the back
reaction of the generic linearized perturbation make the dilaton to run and the
$T^{(1,1)}$ gets squashed which in turn make the supersymmetry to be broken.
But if we make a special linearized perturbation in such way that the
$T^{(1,1)}$ is not squashed then the corresponding perturbation preserve
supersymmetry.


title: The character tables of centralizers in Weyl Group of $E_8$ I

abstract:
  To classify the finite dimensional pointed Hopf algebras with Weyl group $G$
of $E_8$, we obtain the representatives of conjugacy classes of $G$ and all
character tables of centralizers of these representatives by means of software
GAP. In this paper we only list character table 1-- 28.


title: A New Extensions of MSSM: FMSSM

abstract:
  We propose an extension of the MSSM by adding vector like `matter' fields
with masses near the TeV scale. This extension allows us to generate the masses
of the bottom quark and tau lepton via radiative corrections such that only up
type Higgs doublet couples with quarks and leptons. In addition to providing a
natural explanation of the hierarchies between m_{b, \tau} and m_t, this new
extension, which we call FMSSM, allows the heavy sector of the MSSM Higgs
bosons to be essentially fermiophobic as well as gaugephobic. Moreover, in this
scenario there is no upper bound for the parameter \tan \beta . FMSSM can be
distinguished from the MSSM, and has peculiar and unorthodox signals at the
LHC, especially for the Higgs sector.


title:
Milnor-Wood inequalities for manifolds locally isometric to a product of
  hyperbolic planes

abstract:
  This note describes sharp Milnor--Wood inequalities for the Euler number of
flat oriented vector bundles over closed Riemannian manifolds locally isometric
to products of hyperbolic planes. One consequence is that such manifolds do not
admit an affine structure, confirming Chern--Sullivan's conjecture in this
case. The manifolds under consideration are of particular interest, since in
contrary to many other locally symmetric spaces they do admit flat vector
bundle of the corresponding dimension. When the manifold is irreducible and of
higher rank, it is shown that flat oriented vector bundles are determined
completely by the sign of the Euler number.


title: Distributional Matter Tensors in Relativity

abstract:
  This paper uses products of distributions to obtain new junction conditions
for relativistic shocks. In general, the shock is accompanied by a surface
layer, and the new conditions generalize both Taub's jump conditions for
shocks, and those of Israel and Kuchar for surface layers. In the
non-relativistic limit, the surface layer is present only when the fluid is
viscous or thermally conducting--a situation where the classical
Rankine-Hugoniot conditions do not apply. Thus, our conditions properly extend
all previous conditions, and provide complete Cauchy data needed to solve the
full Navier-Stokes equations downstream of the shock. Since the associative law
fails for our product, the residual uncertainty regarding the association of
factors must be eliminated empirically. This is equivalent to fixing the
correct initial_form_ of the equations (such as the ``conservation form'' in
the Euler case)


title: Intersection of subgroups in free groups and homotopy groups

abstract:
  We show that the intersection of three subgroups in a free group is related
to the computation of the third homotopy group $\pi_3$. This generalizes a
result of Gutierrez-Ratcliffe who relate the intersection of two subgroups with
the computation of $\pi_2$. Let $K$ be a two-dimensional CW-complex with
subcomplexes $K_1,K_2,K_3$ such that $K=K_1\cup K_2\cup K_3$ and $K_1\cap
K_2\cap K_3$ is the 1-skeleton $K^1$ of $K$. We construct a natural
homomorphism of $\pi_1(K)$-modules $$ \pi_3(K)\to \frac{R_1\cap R_2\cap
R_3}{[R_1,R_2\cap R_3][R_2,R_3\cap R_1][R_3,R_1\cap R_2]}, $$ where
$R_i=ker\{\pi_1(K^1)\to \pi_1(K_i)\}, i=1,2,3$ and the action of
$\pi_1(K)=F/R_1R_2R_3$ on the right hand abelian group is defined via
conjugation in $F$. In certain cases, the defined map is an isomorphism.
Finally, we discuss certain applications of the above map to group homology.


title: Homotopy types of reduced 2-nilpotent simplicial groups

abstract:
  We classify the homotopy types of reduced 2-nilpotent simplicial groups in
terms of the homology an d boundary invariants $b,\beta$. This contains as
special cases results of J.H.C. Whitehead on 1-connected 4-dimensional
complexes and of Quillen on reduced 2-nilpotent rational simplicial groups.
Moreover it yields for 1-nilpotent (or abelian) simplicial groups a
classification due to Dold-Kan. Our result describes a new natural structure of
the integral homology of any simply connected space. We also classify the
homotopy types of connective spectra in the category of 2-nilpotent simplicial
groups. Moreover we compute homotopy groups of spheres in the category of
$m$-nilpotent groups for $m=2,3$ and partially for $m=4,5$.


title: The character tables of centralizers in Weyl Group of $E_8$ II

abstract:
  To classify the finite dimensional pointed Hopf algebras with Weyl group $G$
of $E_8$, we obtain the representatives of conjugacy classes of $G$ and all
character tables of centralizers of these representatives by means of software
GAP. In this paper we only list character table 29--46.


title: The character tables of centralizers in Weyl Group of $E_8$ III

abstract:
  To classify the finite dimensional pointed Hopf algebras with Weyl group $G$
of $E_8$, we obtain the representatives of conjugacy classes of $G$ and all
character tables of centralizers of these representatives by means of software
GAP. In this paper we only list character table 47--64.


title: Interaction of non-Abelian tensor gauge fields

abstract:
  Recently we introduced an extended vector bundle X on which non-Abelian
tensor gauge fields realize a connection. Our aim here is to introduce
interaction of these non-Abelian tensor gauge fields with fermions and bosons.
We have found that there exist two series of gauge invariant forms describing
this interaction. The linear sum of these forms comprises the general gauge
invariant Lagrangian. Studying the corresponding Euler-Lagrange equations we
found that a particular linear combination of these forms exhibits enhanced
symmetry which guarantees the conservation of the corresponding high-rank
currents. A possible mechanism of symmetry breaking and mass generation of
tensor gauge bosons is suggested.


title: The character tables of centralizers in Weyl Group of $E_8$ IV

abstract:
  To classify the finite dimensional pointed Hopf algebras with Weyl group $G$
of $E_8$, we obtain the representatives of conjugacy classes of $G$ and all
character tables of centralizers of these representatives by means of software
GAP. In this paper we only list character table 65--94.


title: The character tables of centralizers in Weyl Group of $E_8$ V

abstract:
  To classify the finite dimensional pointed Hopf algebras with Weyl group $G$
of $E_8$, we obtain the representatives of conjugacy classes of $G$ and all
character tables of centralizers of these representatives by means of software
GAP. In this paper we only list character table 95--112.


title:
On the problem of completeness of QM: von Neumann against Einstein,
  Podolsky, and Rosen

abstract:
  We performed a comparative analysis of the arguments of Einstein, Podolsky
and Rosen -- EPR, 1935 (against the completeness of QM) and the theoretical
formalism of QM (due to von Neumann, 1932). We found that the EPR
considerations do not match at all with the von Neumann's theory. Thus EPR did
not criticize the real theoretical model of QM. The root of EPR's paradoxical
conclusion on incompleteness of QM is the misuse of von Neumann's projection
postulate. EPR applied this postulate to observables with degenerate spectra
(which is totally forbidden by the axiomatics of QM).


title: Strong magnetic spiral pattern in a ringed galaxy NGC4736

abstract:
  We present high sensitivity radio polarimetric (VLA) observations of a galaxy
with strong orbital resonances - NGC4736. The total radio intensity at 8.4GHz
covers smoothly the whole galaxy bulge and reveals a distinct ring of radio
emission closely related to the ring morphology visible in infrared, CO and
Halpha emission. However, the magnetic field reveals a very coherent spiral
pattern. The magnetic field vectors are crossing the inner starbursting ring,
the dust lanes within the ring and other rather circularly shaped features
visible in other gas traces. Either the magnetic field uncovers the pattern of
gas motions not seen in other spectral ranges, or the spiral magnetic field is
of a pure dynamo origin, ignoring the ringed morphology of the galaxy.


title:
The Twin Paradox Revisited and Reformulated -- On the Possibility of
  Detecting Absolute Motion

abstract:
  The famous twin paradox of the Special Theory of Relativity by Einstein
(1905) is revisited and revised. This paradox is not a paradox in the true
sense of a paradox but a reflection of a misunderstanding of the problem and
the Principle of Relativity. The currently accepted solution to this takes into
account the accelerations and deceleration of the traveling twin thus
introducing an asymmetry that solves the paradox. We argue here that, with the
acceleration and deceleration neglected, the problem is asymmetric hence
leading to the same conclusion that the traveling twin will age less than the
stay at home. We introduce a symmetric twin paradox whose solution can not be
found within the currently accepted provinces of the STR if one adopts the
currently accepted philosophy of the STR namely that it is impossible for an
inertial observer to determine their state of motion. To resolve this, we
present (in our modest view) a simple and convincing argument that leads us to
conclude that it must be possible for an inertial observer to determine their
own state of motion. With this, we are able to solve the symmetric twin
paradox. The fact that it is possible for an inertial observer to determine
their state of motion -- brings us back to the long rejected idea of an all
pervading and permeating medium -- the Aether, namely the Lorentz luminiferous
Aether. An experiment capable of validating or invalidating this claim is
suggested.


title: Oscillating pulsar polar gaps

abstract:
  An analytical model for oscillating pair creation above the pulsar polar cap
is presented in which the parallel electric field is treated as a large
amplitude, superluminal, electrostatic wave. An exact formalism for such wave
is derived in one-dimension and applied to both the low-density regime in which
the pair plasma density is much lower than the corotating charge density and
the high-density regime in which the pair plasma density is much higher than
the corotating charge density. In the low-density regime, which is relevant
during the phase leading to a pair cascade, a parallel electric field develops
resulting in rapid acceleration of particles. The rapid acceleration leads to
bursts of pair production and the system switches to the oscillatory phase,
corresponding to the high density regime, in which pairs oscillate with net
drift motion in the direction of wave propagation. Oscillating pairs lead to a
current that oscillates with large amplitude about the Goldreich-Julian
current. The drift motion can be highly relativistic if the phase speed of
large amplitude waves is moderately higher than the speed of light. Thus, the
model predicts a relativistic outflow of pairs, a feature that is required for
avoiding overheating of the pulsar polar cap and is also needed for the pulsar
wind.


title: Dynamical Friction of Double Perturbers in a Gaseous Medium

abstract:
  In many astrophysical situations, as in the coalescence of supermassive black
hole pairs at gas rich galactic nuclei, the dynamical friction experienced by
an object is a combination of its own wake as well as the wakes of its
companions. Using a semi-analytic approach, we investigate the composite wake
due to, and the resulting drag forces on, double perturbers that are placed at
the opposite sides of the orbital center and move on a circular orbit in a
uniform gaseous medium. The circular orbit makes the wake of each perturber
asymmetric, creating an overdense tail at the trailing side. The tail not only
drags the perturber backward but it also exerts a positive torque on the
companion. For equal-mass perturbers, the positive torque created by the
companion wake is, on average, a fraction ~40-50% of the negative torque
created by its own wake, but this fraction may be even larger for perturbers
moving subsonically. This suggests that the orbital decay of a perturber in a
double system, especially in the subsonic regime, can take considerably longer
than in isolation. We provide the fitting formulae for the forces due to the
companion wake and discuss our results in light of recent numerical simulations
for mergers of binary black holes.


title:
Linked $\mathcal{PT }$-symmetry to Supersymmetry in a class of
  non-Hermitian Hamiltonians

abstract:
  We introduce and study a class of non-Hermitian Hamiltonians which have
velocity dependent potentials. Since stability can not be advocated directly
from the classical potential, we show that the energy spectra are real and
bounded from below which proves the stability of the spectra of all members in
the class. We find that the introduced class of non-Hermitian Hamiltonians do
have a corresponding superpartner class of non-Hermitian Hamiltonians. We were
able to introduce supercharges which in conjunction with the corresponding
super Hamiltonians constitute a closed super algebra. Among the introduced
Hamiltonians, we show that non-$\mathcal{PT }$-symmetric Hamiltonians can be
transformed into their corresponding superpartner Hamiltonians via a specific
canonical transformation while the $\mathcal{PT }$-symmetric ones failed to be
mapped to their corresponding superpartner Hamiltonians via the same canonical
transformation. Since canonical transformations preserve the spectrum, we
conclude that non-$\mathcal{PT }$-symmetric Hamiltonians out of the introduced
class of Hamiltonians have the same spectrum as the corresponding superpartner
Hamiltonians and thus Susy is broken for such Hamiltonians. This kind of
intertwining of $\mathcal{PT }$-symmetry and Supersymmetry is new as all the so
far discussed cases concentrate on Hamiltonians of broken $\mathcal{PT }%
$-symmetry that have broken Supersymmetry too while we showed that Susy can be
also broken for non-$\mathcal{PT }$-symmetric and non-Hermitian Hamiltonians .


title: Rouquier blocks of the cyclotomic Ariki-Koike algebras

abstract:
  The definition of Rouquier for the families of characters of Weyl groups in
terms of blocks of the associated Iwahori-Hecke algebra has made possible the
generalization of this notion to the complex reflection groups. Here we give an
algorithm for the determination of the "Rouquier blocks" of the cyclotomic
Ariki-Koike algebras.


title: Direct photons as probes of low mass strings at the LHC

abstract:
  The LHC program will include the identification of events with single prompt
high-k_\perp photons as probes of new physics. We show that this channel is
uniquely suited to search for experimental evidence of TeV-scale open string
theory. At the parton level, we analyze single photon production in gluon
fusion, gg \to \gamma g, with open string states propagating in intermediate
channels. If the photon mixes with the gauge boson of the baryon number, which
is a common feature of D-brane quivers, the amplitude appears already at the
string disk level. It is completely determined by the mixing parameter (which
is actually determined in the minimal theory) -- and it is otherwise
model-(compactification-) independent. We discuss the string signal cross
sections as well as the QCD background. The present analysis takes into account
the recently obtained decay widths of first Regge recurrences, which are
necessary for more precise determination of these cross sections in the
resonant region. A vital part of the background discussion concerns the
minimization of misidentified \pi^0's emerging from high-p_\perp jets. We show
that even for relatively small mixing, 100 fb^-1 of LHC data could probe
deviations from standard model physics associated with TeV-scale strings at a
5\sigma significance, for M_{\rm string} as large as 2.3 TeV. It is also likely
that resonant bumps could be observed with approximately the same
signal-to-noise ratio.


title: A multiplication formula for module subcategories of Ext-symmetry

abstract:
  We define evaluation forms associated to objects in a module subcategory of
Ext-symmetry generated by finitely many simple modules over a path algebra with
relations and prove a multiplication formula for the product of two evaluation
forms. It is analogous to a multiplication formula for the product of two
evaluation forms associated to modules over a preprojective algebra given by
Geiss, Leclerc and Schr\"oer in \cite{GLS2006}.


title: Green formula in Hall algebras and cluster algebras

abstract:
  The objective of the present paper is to give a survey of recent progress on
applications of the approaches of Ringel-Hall type algebras to quantum groups
and cluster algebras via various forms of Green's formula. In this paper, three
forms of Green's formula are highlighted, (1) the original form of Green's
formula \cite{Green}\cite{RingelGreen}, (2) the degeneration form of Green's
formula \cite{DXX} and (3) the projective form of Green's formula
\cite{XX2007a} i.e. Green formula with a $\bbc^{*}$-action.


title:
Electronic Structure and Optical Properties of Silicon Nanocrystals
  along their Aggregation Stages

abstract:
  The structural control of silicon nanocrystals is an important technological
problem. Typically a distribution of nanocrystal sizes and shapes emerges under
the uncontrolled aggregation of smaller clusters. The aim of this computational
study is to investigate the evolution of the nanocrystal electronic states and
their optical properties throughout their aggregation stages. To realistically
tackle such systems, an atomistic electronic structure tool is required that
can accommodate about tens of thousand nanocrystal and embedding lattice atoms
with very irregular shapes. For this purpose, a computationally-efficient
pseudopotential-based electronic structure tool is developed that can handle
realistic nanostructures based on the expansion of the wavefunction of the
aggregate in terms of bulk Bloch bands of the constituent semiconductors. With
this tool, the evolution of the electronic states as well as the
polarization-dependent absorption spectra correlated with the oscillator
strengths over their aggregation stages are traced. The low-lying aggregate
nanocrystal states develop binding and anti-binding counterparts of the
isolated states. Such information may become instrumental with the maturity of
the controlled aggregation of these nanocrystals.


title: Tachyon Solution in Cubic Neveu-Schwarz String Field Theory

abstract:
  A class of exact analytic solutions in the modified cubic fermionic string
field theory with the GSO(-) sector is presented. This class contains the
GSO(-) tachyon field and reproduces the correct value for the nonBPS D-brane
tension.


title: On a Class of Polynomials with Integer Coefficients

abstract:
  A class P_{n,m,p}(x) of polynomials is defined. The combinatorial meaning of
its coefficients is given. Chebyshev polynomials are the special cases of
P_{n,m,p}(x). It is first shown that P_{n,m,p}(x) may be expressed in terms of
P_{n,0,p}(x). From this we derive that P_{n,2,2}(x) may be obtain in terms of
trigonometric functions, from which we obtain some of its important properties.
Some questions about orthogonality are also concerned. Furthermore, it is shown
that P_{n,2,2}(x) fulfills the same three terms recurrence as Chebyshev
polynomials. Some others recurrences for P_{n,m,p}(x) and its coefficients are
also obtained. At the end a formula for coefficients of Chebyshev polynomials
of the second kind is derived.


title:
eta-prime Meson Production in Nucleon-Nucleon Collisions Near The
  Threshold

abstract:
  The production of $\eta'$ mesons in the reactions $pp\to pp\eta'$ and $pn\to
pn\eta' $ at threshold-near energies is analyzed within a covariant effective
meson-nucleon theory. The description of cross section and angular
distributions of the available data in this kinematical region in the $pp$
channel is accomplished by including meson currents and nucleon currents with
the resonances $S_{11}(1650)$, $P_{11}(1710)$ and $P_{13}(1720)$. Predictions
for the $pn$ channel are given. The di-electron production from subsequent
$\eta'$ Dalitz decay $\eta' \to \gamma \gamma^* \to\gamma e^+e^-$ is also
calculated and numerical results are presented for intermediate energy and
kinematics of possible experiments with HADES, CLAS and KEK-PS.


title:
Infinitely many local higher symmetries without recursion operator or
  master symmetry: integrability of the Foursov--Burgers system revisited

abstract:
  We consider the Burgers-type system studied by Foursov, w_t &=& w_{xx} + 8 w
w_x + (2-4\alpha)z z_x, z_t &=& (1-2\alpha)z_{xx} - 4\alpha z w_x +
(4-8\alpha)w z_x - (4+8\alpha)w^2 z + (-2+4\alpha)z^3, (*) for which no
recursion operator or master symmetry was known so far, and prove that the
system (*) admits infinitely many local generalized symmetries that are
constructed using a nonlocal {\em two-term} recursion relation rather than from
a recursion operator.


abstract:
  We present the mini-proceedings of the workshop on ``Parton fragmentation in
the vacuum and in the medium'' held at the European Centre for Theoretical
Studies in Nuclear Physics and Related Areas (ECT*, Trento) in February 2008.
The workshop gathered both theorists and experimentalists to discuss the
current status of investigations of quark and gluon fragmentation into hadrons
at different accelerator facilities (LEP, B-factories, JLab, HERA, RHIC, and
Tevatron) as well as preparations for extension of these studies at the LHC.
The main physics topics covered were: (i) light-quark and gluon fragmentation
in the vacuum including theoretical (global fits analyses and MLLA) and
experimental (data from e+e-, p-p, e-p collisions) aspects, (ii) strange and
heavy-quark fragmentation, (iii) parton fragmentation in cold QCD matter
(nuclear DIS), and (iv) medium-modified fragmentation in hot and dense QCD
matter (high-energy nucleus-nucleus collisions). These mini-proceedings consist
of an introduction and short summaries of the talks presented at the meeting.


title: Compacton-like solutions to some nonlocal hydrodynamic-type model

abstract:
  We study the appearance of compacton-like solutions within the
hydrodynamic-type model taking into account effects of spatial non-locality


title:
Molecular random walks in a fluid and an invariance group of the
  Bogolyubov generating functional equation

abstract:
  The problem of statistics of molecular random walks in a classical fluid is
analyzed by means of the BBGKY hierarchy of equations reformulated in terms of
the Bogolyubov evolution equation for generating functional of many-particle
distribution functions. A proper equivalent set of correlation functions is
introduced so that all they are integrable, vanish in statistical equilibrium,
otherwise accumulate statistical information about history of collisions of a
``molecular Brownian particle'' (test molecule) with other molecules of the
fluid. An exact evolution equation for generating functional of such
correlation functions is derived. Then it is shown that time-dependent solution
to this equation, as well as a properly defined generating functional of static
thermodynamically equilibrium correlations, possesses invariance with respect
to a definite group of transformations of independent variables of the
functional, if density of the fluid (number of molecules per unit volume) is
treated as one of the independent variables. Such invariance results in
infinitely many exact relations between the correlation functions and
probability distribution of path of the molecular Brownian particle. Even
simplest of these relations suggest significant restrictions on a profile of
the path probability distribution, even without literal solving the BBGKY
hierarchy.


title: Cooperative Spontaneous Emission as a Many Body Eigenvalue Problem

abstract:
  We study emission of a single photon from a spherically symmetric cloud of N
atoms (one atom is excited, N-1 are in ground state) and present an exact
analytical expression for eigenvalues and eigenstates of this many body
problem. We found that some states decay much faster then the single-atom decay
rate, while other states are trapped and undergo very slow decay. When size of
the atomic cloud is small compared with the radiation wave length we found that
the radiation frequency undergoes a large shift.


title: An ACS Survey of Globular Clusters V: Star Catalog for Each Cluster

abstract:
  The ACS Survey of Globular Clusters has used HST's Wide-Field Channel to
obtain uniform imaging of 65 of the nearest globular clusters to provide an
extensive homogeneous dataset for a broad range of scientific investigations.
The survey goals required not only a uniform observing strategy, but also a
uniform reduction strategy. To this end, we designed a sophisticated software
program to process the cluster data in an automated way. The program identifies
stars simultaneously in the multiple dithered exposures for each cluster and
measures them using the best available PSF models. We describe here in detail
the program's rationale, algorithms, and output. The routine was also designed
to perform artificial-star tests, and we run a standard set of ~10^5 tests for
each cluster in the survey. The catalog described here will be exploited in a
number of upcoming papers and will eventually be made available to the public
via the world-wide web.


title:
A Case Study of Gender Bias at the Postdoctoral Level in Physics, and
  its Resulting Impact on the Academic Career Advancement of Females

abstract:
  This case study of a typical U.S. particle physics experiment explores the
issues of gender bias and how it affects the academic career advancement
prospects of women in the field of physics beyond the postdoctoral level; we
use public databases to study the career paths of the full cohort of 57 former
postdoctoral researchers on the Run II Dzero experiment to examine if males and
females were treated in a gender-blind fashion on the experiment.
  The study finds that the female researchers were on average significantly
more productive compared to their male peers, yet were allocated only 1/3 the
amount of conference presentations based on their productivity. The study also
finds that the dramatic gender bias in allocation of conference presentations
appeared to have significant negative impact on the academic career advancement
of the females.
  The author has a PhD in particle physics and worked for six years as a
postdoctoral research scientist, five of which were spent collaborating at
Fermilab. She is currently completing a graduate degree in statistics.


title: Quantum aspects of a noncommutative supersymmetric kink

abstract:
  We consider quantum corrections to a kink of noncommutative supersymmetric
phi^4 theory in 1+1 dimensions. Despite the presence of an infinite number of
time derivatives in the action, we are able to define supercharges and a
Hamiltonian by using an unconventional canonical formalism. We calculate the
quantum energy E of the kink (defined as a half-sum of the eigenfrequencies of
fluctuations) which coincides with its' value in corresponding commutative
theory independently of the noncommutativity parameter. The renormalization
also proceeds precisely as in the commutative case. The vacuum expectation
value of the new Hamiltonian is also calculated and appears to be consistent
with the value of the quantum energy E of the kink.


title:
Noncommutative associative superproduct for general supersymplectic
  forms

abstract:
  We define a noncommutative and nonanticommutative associative product for
general supersymplectic forms, allowing the explicit treatment of
non(anti)commutative field theories from general nonconstant string backgrounds
like a graviphoton field. We propose a generalization of deformation
quantization a la Fedosov to superspace, which considers noncommutativity in
the tangent bundle instead of base space, by defining the Weyl super product of
elements of Weyl super algebra bundles. Super Poincare symmetry is not broken
and chirality seems not to be compromised in our formulation. We show that, for
a particular case, the projection of the Weyl super product to the base space
gives rise the Moyal product for non(anti)commutative theories.


title: Stationary distributions for diffusions with inert drift

abstract:
  Consider a reflecting diffusion in a domain in $R^d$ that acquires drift in
proportion to the amount of local time spent on the boundary of the domain. We
show that the stationary distribution for the joint law of the position of the
reflecting process and the value of the drift vector has a product form.
Moreover, the first component is the symmetrizing measure on the domain for the
reflecting diffusion without inert drift, and the second component has a
Gaussian distribution. We also consider processes where the drift is given in
terms of the gradient of a potential.


title: The Nature and Geometry of the Light Echo from SN 2006X

abstract:
  We report on the discovery of the geometry producing the light echo emanating
from Supernova 2006X, a nearby but underluminous Type Ia in M100 (= NGC 4321).
This offers a rare chance to study the environment of a Type Ia supernova.
Contrary to previous reports, there is little evidence of a circumstellar
component in the light echo morphology or in the light curve of the unresolved
SN point source. Instead, the obvious and dominant echo contribution comes from
what is probably a relatively thin sheet of material some 26 pc in front of SN
2006X. Of the four known Type Ia light echoes, three show no evidence of a
circumstellar echo and the fourth needs to be confirmed. We consider other
evidence for circumstellar material around SN Ia, which may be rare.


title: On the spectral parameter problem

abstract:
  We consider the problem whether a nonparametric zero-curvature representation
can be embedded into a one-parameter family within the same Lie algebra. After
introducing a computable cohomological obstruction, a method using the
recursion operator to incorporate the parameter is discussed.


title: Tight Bounds and Faster Algorithms for Directed Max-Leaf Problems

abstract:
  An out-tree $T$ of a directed graph $D$ is a rooted tree subgraph with all
arcs directed outwards from the root. An out-branching is a spanning out-tree.
By $l(D)$ and $l_s(D)$ we denote the maximum number of leaves over all
out-trees and out-branchings of $D$, respectively.
  We give fixed parameter tractable algorithms for deciding whether $l_s(D)\geq
k$ and whether $l(D)\geq k$ for a digraph $D$ on $n$ vertices, both with time
complexity $2^{O(k\log k)} \cdot n^{O(1)}$. This improves on previous
algorithms with complexity $2^{O(k^3\log k)} \cdot n^{O(1)}$ and $2^{O(k\log^2
k)} \cdot n^{O(1)}$, respectively.
  To obtain the complexity bound in the case of out-branchings, we prove that
when all arcs of $D$ are part of at least one out-branching, $l_s(D)\geq
l(D)/3$. The second bound we prove in this paper states that for strongly
connected digraphs $D$ with minimum in-degree 3, $l_s(D)\geq \Theta(\sqrt{n})$,
where previously $l_s(D)\geq \Theta(\sqrt[3]{n})$ was the best known bound.
This bound is tight, and also holds for the larger class of digraphs with
minimum in-degree 3 in which every arc is part of at least one out-branching.


title: On The Criteria Of The F5 Algorithm

abstract:
  Faugere's F5 algorithm is one of the fastest known algorithms for the
computation of Grobner bases. So far only the F5 Criterion is proved, whereas
the second powerful criterion, the Rewritten Criterion, is not understood very
well until now. We give a proof of both, the F5 Criterion and the Rewritten
Criterion showing their connection to syzygies, i.e. the relations between the
S-Polynomials to be investigated by the algorithm. Using the example of a
Grobner basis computation stated in Faugere's F5 paper we show how the criteria
work, and discuss the possibility of improving the F5 Criterion. An
introduction to a SINGULAR implementation of F5 is given in the end.


title:
Positivity and the canonical basis of tensor products of
  finite-dimensional irreducible representations of quantum sl(k)

abstract:
  In a categorification of tensor products of fundamental representations of
quantum sl(k) via highest weight categories, the indecomposable tilting modules
descend to the canonical basis. Since projective functors map tilting modules
to tilting modules, the coefficients of the canonical basis of tensor products
of finite dimensional, irreducible representations under the action of the
Chevalley generators are positive.


title: The non-anticipation of the asynchronous systems

abstract:
  The asynchronous systems are the models of the asynchronous circuits from the
digital electrical engineering and non-anticipation is one of the most
important properties in systems theory. Our present purpose is to introduce
several concepts of non-anticipation of the asynchronous systems.


title: Towards Physarum robots: computing and manipulating on water surface

abstract:
  Plasmodium of Physarym polycephalum is an ideal biological substrate for
implementing concurrent and parallel computation, including combinatorial
geometry and optimization on graphs. We report results of scoping experiments
on Physarum computing in conditions of minimal friction, on the water surface.
We show that plasmodium of Physarum is capable for computing a basic spanning
trees and manipulating of light-weight objects. We speculate that our results
pave the pathways towards design and implementation of amorphous biological
robots.


title: Some properties of the regular asynchronous systems

abstract:
  The asynchronous systems are the models of the asynchronous circuits from the
digital electrical engineering. An asynchronous system f is a multi-valued
function that assigns to each admissible input u a set f(u) of possible states
x in f(u). A special case of asynchronous system consists in the existence of a
Boolean function \Upsilon such that for any u and any x in f(u), a certain
equation involving \Upsilon is fulfilled. Then \Upsilon is called the generator
function of f (Moisil used the terminology of network function) and we say that
f is generated by \Upsilon. The systems that have a generator function are
called regular.
  Our purpose is to continue the study of the generation of the asynchronous
systems that was started in [2], [3].


title:
On the representations of integers by the sextenary quadratic form
  x^2+y^2+z^2+ 7s^2+7t^2+ 7u^2 and 7-cores

abstract:
  In this paper we derive an explicit formula for the number of representations
of an integer by the sextenary form x^2+y^2+z^2+ 7s^2+7t^2+ 7u^2. We establish
the following intriguing inequalities 2b(n)>=a_7(n)>=b(n) for n not equal to
0,2,6,16.
  Here a_7(n) is the number of partitions of n that are 7-cores and b(n) is the
number of representations of n+2 by the sextenary form (x ^2+ y ^2+z ^2+ 7s ^2
+ 7t ^2+ 7u^2)/8 with x,y,z,s,t and u being odd.


title:
Critical behavior and the limit distribution for long-range oriented
  percolation. II: Spatial correlation

abstract:
  We prove that the Fourier transform of the properly-scaled normalized
two-point function for sufficiently spread-out long-range oriented percolation
with index \alpha>0 converges to e^{-C|k|^{\alpha\wedge2}} for some
C\in(0,\infty) above the upper-critical dimension 2(\alpha\wedge2). This
answers the open question remained in the previous paper [arXiv:math/0703455].
Moreover, we show that the constant C exhibits crossover at \alpha=2, which is
a result of interactions among occupied paths. The proof is based on a new
method of estimating fractional moments for the spatial variable of the
lace-expansion coefficients.


title:
Evidence of the role of contacts on the observed electron-hole asymmetry
  in graphene

abstract:
  We perform electrical transport measurements in graphene with several sample
geometries. In particular, we design ``invasive'' probes crossing the whole
graphene sheet as well as ``external'' probes connected through graphene side
arms. The four-probe conductance measured between external probes varies
linearly with charge density and is symmetric between electron and hole types
of carriers. In contrast measurements with invasive probes give a strong
electron-hole asymmetry and a sub-linear conductance as a function of density.
By comparing various geometries and types of contact metal, we show that these
two observations are due to transport properties of the metal/graphene
interface. The asymmetry originates from the pinning of the charge density
below the metal, which thereby forms a p-n or p-p junction depending on the
polarity of the carriers in the bulk graphene sheet. Our results also explain
part of the sub-linearity observed in conductance as a function of density in a
large number of experiments on graphene, which has generally been attributed to
short-range scattering only.


title:
Modular representations of reductive groups and geometry of affine
  Grassmannians

abstract:
  By the geometric Satake isomorphism of Mirkovic and Vilonen, decomposition
numbers for reductive groups can be interpreted as decomposition numbers for
equivariant perverse sheaves on the complex affine Grassmannian of the
Langlands dual group. Using a description of the minimal degenerations of the
affine Grassmannian obtained by Malkin, Ostrik and Vybornov, we are able to
recover geometrically some decomposition numbers for reductive groups. In the
other direction, we can use some decomposition numbers for reductive groups to
prove geometric results, such as a new proof of non-smoothness results, and a
proof that some singularities are not equivalent (a conjecture of Malkin,
Ostrik and Vybornov). We also give counterexamples to a conjecture of Mirkovic
and Vilonen stating that the stalks of standard perverse sheaves over the
integers on the affine Grassmannian are torsion-free, and propose a modified
conjecture, excluding bad primes.


title: Brane world corrections to scalar vacuum force in RSII-p

abstract:
  Vacuum force is an interesting low energy test for brane worlds due to its
dependence on field's modes and its role in submillimeter gravity experiments.
In this work we generalize a previous model example: the scalar field vacuum
force between two parallel plates lying in the brane of a Randall-Sundrum
scenario extended by $p$ compact dimensions (RSII-$p$). Upon use of Green's
function technique, for the massless scalar field, the 4D force is obtained
from a zero mode while corrections turn out attractive and depend on the
separation between plates as $l^{-(6+p)}$. For the massive scalar field a
quasilocalized mode yields the 4D force with attractive corrections behaving
like $l^{-(10+p)}$. Corrections are negligible w.r.t. 4D force for
$AdS_{(5+p)}$ radius less than $\sim 10^{-6}$m. Although the $p=0$ case is not
physically viable due to the different behavior in regard to localization for
the massless scalar and electromagnetic fields it yields an useful comparison
between the dimensional regularization and Green's function techniques as we
describe in the discussion.


title:
Analytical correlation of routing table length index and routing path
  length index in hierarchical routing model

abstract:
  In Kleinrock and Kamoun's paper, the inverse relation of routing table length
index and routing path length index in hierarchical routing model is
illustrated. In this paper we give the analytical correlation of routing table
length index and routing path length index in hierarchical routing model.


title:
QED in finite volume and finite size scaling effect on electromagnetic
  properties of hadrons

abstract:
  On account of its application to the present and future analysis of the
virtual photon correction to the hadronic properties by means of lattice QCD
simulation, we initiate the study of the finite size scaling effect on the QED
correction using low energy effective theory of QCD with QED. For this purpose,
we begin with formulating a new QED on the space with finite volume. By
adapting this formalism to the partially quenched QCD with electromagnetism, we
explore the qualitative features of the finite size scaling effect on the
electromagnetic correction to the masses of pseudo-Goldstone bosons.


title: Correlation between regions of star formation and gamma-ray sources

abstract:
  Statistically significant correlation between positions of unidentified
gamma-ray sources (UGS) and the regions of star formation (RSF) is found.
Fraction of UGS, coincided in position with RSF, makes up $47\pm 8$%. The
coincided discrete gamma-ray sources possess, on average, harder energetic
spectra and larger intensities with respect to the rest UGS. Annihilation of
dark matter concentrating in RSF is supposed to account for a possible origin
of gamma-radiation.


title: Bousso entropy bound for ideal gas of massive particles

abstract:
  The Bousso entropy bound is investigated for static spherically symmetric
configurations of ideal gas with Bose-Einstein and Fermi-Dirac distribution
function. Gas of massive particles is considered. The paper is continuation of
the previous work concerning the massless case. Special attention is devoted to
lightsheets generated by spheres. Conditions under which the Bousso bound can
be violated are discussed and it is shown that a possible violating region
cannot be arbitrarily large and that it is contained inside a sphere of unit
Planck radius if the number of independent spin states $g_s$ is small enough.
It is also shown that the central temperature must exceed the Planck
temperature in order to get a violation of the Bousso bound for $g_s$ not too
large. The situation for higher-dimensional spacetimes is also discussed and
the FMW conditions are investigated.


title: Quantum Bayesianism: A Study

abstract:
  The Bayesian approach to quantum mechanics of Caves, Fuchs and Schack is
presented. Its conjunction of realism about physics along with anti-realism
about much of the structure of quantum theory is elaborated; and the position
defended from common objections: that it is solipsist; that it is too
instrumentalist; that it cannot deal with Wigner's friend scenarios. Three more
substantive problems are raised: Can a reasonable ontology be found for the
approach? Can it account for explanation in quantum theory? Are subjective
probabilities on their own adequate in the quantum domain? The first question
is answered in the affirmative, drawing on elements from Nancy Cartwright's
philosophy of science. The second two are not: it is argued that these present
outstanding difficulties for the project. A quantum Bayesian version of Moore's
paradox is developed to illustrate difficulties with the subjectivist account
of pure state assignments.


title: The classification on simple Moufang loops

abstract:
  Let $C(F)$ be a matrix Cayley-Dickson algebra over field $F$. By $M_0(F)$ we
denote the loop containing of all elements of algebra $C(F)$ with norm 1. It is
shown in this paper that with precision till isomorphism the loops
$M_0(F)/<-1>$ they and only they are simple non-associative Moufang loops,
where $F$ are subfields of algebraic closed field


title: About the embedding of Moufang loops in alternative algebras II

abstract:
  It is known that with precision till isomorphism that only and only loops
$M(F) = M_0(F)/<-1>$, where $M_0(F)$ denotes the loop, consisting from elements
of all matrix Cayley-Dickson algebra $C(F)$ with norm 1, and $F$ be a subfield
of arbitrary fixed algebraically closed field, are simple non-associative
Moufang loops. In this paper it is proved that the simple loops $M(F)$ they and
only they are not embedded into a loops of invertible elements of any unitaly
alternative algebras if $\text{char} F \neq 2$ and $F$ is closed under square
root operation. For the remaining Moufang loops such an embedding is possible.
Using this embedding it is quite simple to prove the well-known finding: the
finite Moufang $p$-loop is centrally nilpotent.


abstract:
  Stochastic chains with memory of variable length constitute an interesting
family of stochastic chains of infinite order on a finite alphabet. The idea is
that for each past, only a finite suffix of the past, called context, is enough
to predict the next symbol. These models were first introduced in the
information theory literature by Rissanen (1983) as a universal tool to perform
data compression. Recently, they have been used to model up scientific data in
areas as different as biology, linguistics and music. This paper presents a
personal introductory guide to this class of models focusing on the algorithm
Context and its rate of convergence.


title: On "non-Hermitian Quantum Mechanics"

abstract:
  A series of recent papers ``Faster than Hermitian Quantum Mechanics'' and
related articles made a point of the possibility of a non-Hermitian, but
PT-symmetric, operator to play the role of a Hamiltonian. In particular, they
show that with an appropriate choice of an inner product, the evolution
generated by such an operator will conserve the norm and scalar product. Here
we observe that if one chooses such an inner product then the Hamiltonian in
question is actually Hermitian, and the whole exercise is to a certain degree
redundant.


title: A symmetric version of Kontsevich graph complex and Leibniz homology

abstract:
  Kontsevich has proven that the Lie homology of the Lie algebra of symplectic
vector fields can be computed in terms of the homology of a graph complex. We
prove that the Leibniz homology of this Lie algebra can be computed in terms of
the homology of a variant of the graph complex endowed with an action of the
symmetric groups. The resulting isomorphism is shown to be a
Zinbiel-associative bialgebra isomorphism.


title:
Superconductivity at 55 K in iron-based F-doped layered quaternary
  compound Sm[O1-xFx]FeAs

abstract:
  Here we report the superconductivity in the iron-based oxyarsenide
Sm[O1-xFx]FeAs, with the onset resistivity transition temperature at 55.0 K and
Meissner transition at 54.6 K. This compound has the same crystal structure as
LaOFeAs with shrunk crystal lattices, and becomes the superconductor with the
highest critical temperature among all materials besides copper oxides.


title: Characteristics, Effects and Life Expectancy of a Primeval Photon

abstract:
  If a photon fluctuates from 'nothing', what would it look like and how would
it behave? Here we examine such a photon and the possible characteristics and
effects it may have. If contrary to theoretical expectation, it is not
short-lived, we find quantitative and qualitative similarities with the
quantitative and qualitative features of the standard big bang model. As it
also seems devoid of some of the horizon, homogenous, flatness, singularity and
temperature problems that plague the big bang model, issues surrounding this
photon's life expectancy may need to be re-visited by cosmologists.


title: How occasional backstepping can speed up a processive motor protein

abstract:
  Fueled by the hydrolysis of ATP, the motor protein kinesin literally walks on
two legs along the biopolymer microtubule. The number of accidental backsteps
that kinesin takes appears to be much larger than what one would expect given
the amount of free energy that ATP hydrolysis makes available. This is puzzling
as more than a billion years of natural selection should have optimized the
motor protein for its speed and efficiency. But more backstepping allows for
the production of more entropy. Such entropy production will make free energy
available. With this additional free energy, the catalytic cycle of the kinesin
can be speeded up. We show how measured backstep percentages represent an
optimum at which maximal net forward speed is achieved.

categories: q-bio.SC cond-mat.stat-mech physics.bio-ph q-bio.QM


title: Spontaneous CP Violation in next to minimal renormalizable SUSY SO(10)

abstract:
  The minimal renormalizable SUSY SO(10) model is a very compact and predictive
theory. It was very popular till one realized that it cannot account for the
masses of the neutrinos. The best cure to this problem is to add the 120 Higgs
representaion, the 'next to minimal' version. To reduce the number of free
parameters, it was suggested in recent papers to use only real parameters in
the superpotential and induce CP violation via complex VEVs. This is what one
usually calls 'spontaneous CP violation'. The number of free parameters turned
out, then, to be even smaller than in the original minimal model and good fits
to all known masses and mixings were obtained. Out of those papers only that of
Aulakh and Garg discusses how CP is spontaneously violated. Some heavy MSSM
singlet VEVs generate a phase at high scale and CP violationis carried down to
the CKM matrix by the mixing of the scalar MSSM doublets. They study the model
in great detail and give a large set of solutions. As a proof of principle, two
of the solutions are shown to induce realistic phenomenological fits. It is not
clear, however, how the right physical solution is obtained. I study the way
solutions for spontaneous CP violation affect the scalar potential. The one
that gives the lowest minimum of the potential, in terms of a given set of
parameters, is the right physical one. In the way of doing so, I will prove
that complex MSSM singlet VEVs lead actually to lower minima than the real (CP
conserving) ones. This proves that CP is spontaneously violated in this model.


title: Comparing and Combining Methods for Automatic Query Expansion

abstract:
  Query expansion is a well known method to improve the performance of
information retrieval systems. In this work we have tested different approaches
to extract the candidate query terms from the top ranked documents returned by
the first-pass retrieval.
  One of them is the cooccurrence approach, based on measures of cooccurrence
of the candidate and the query terms in the retrieved documents. The other one,
the probabilistic approach, is based on the probability distribution of terms
in the collection and in the top ranked set.
  We compare the retrieval improvement achieved by expanding the query with
terms obtained with different methods belonging to both approaches. Besides, we
have developed a na\"ive combination of both kinds of method, with which we
have obtained results that improve those obtained with any of them separately.
This result confirms that the information provided by each approach is of a
different nature and, therefore, can be used in a combined manner.


title: Physical Layer Network Coding Over Finite And Infinite Fields

abstract:
  Direct application of network coding at the physical layer - physical layer
network coding (PNC) - is a promising technique for two-way relay wireless
networks. In a two-way relay network, relay nodes are used to relay two-way
information flows between pairs of end nodes. This paper proposes a precise
definition for PNC. Specifically, in PNC, a relay node does not decode the
source information from the two ends separately, but rather directly maps the
combined signals received simultaneously to a signal to be relayed. Based on
this definition, PNC can be further sub-classed into two categories - PNCF (PNC
over finite field) and PNCI (PNC over infinite field) - according to whether
the network-code field (or groups, rings) adopted is finite or infinite. For
each of PNCF and PNCI, we consider two specific estimation techniques for
dealing with noise in the mapping process. The performance of the four schemes
is investigated by means of analysis and simulation, assuming symbol-level
synchronization only.


title: Higher dimensional Hermitian Gray manifolds

abstract:
  The aim of this paper is to describe a large class of Hermitian Gray
manifolds.


title: A minimal model for kinetic arrest

abstract:
  To elucidate slow dynamics in glassy materials, we introduce the {\it
Figure-8 model} in which $N$ hard blocks undergo Brownian motion around a
circuit in the shape of a figure-8. This system undergoes kinetic arrest at a
critical packing fraction $\phi=\phi_g < 1$, and for $\phi\approx\phi_g$
long-time diffusion is controlled by rare, cooperative `junction-crossing'
particle rearrangements. We find that the average time between junction
crossings $\tau_{JC}$, and hence the structural relaxation time, does not
simply scale with the configurational volume $\OmegaLow$ of transition states,
because $\tau_{JC}$ also depends on the time to complete a junction crossing.
The importance of these results in understanding cage-breaking dynamics in
glassy systems is discussed.


title: Chiral tunneling through time-periodic potential in graphene

abstract:
  Chiral tunneling through a harmonically driven potential barrier in graphene
monolayer is considered in this work. Since the quasiparticles in this system
are chiral in nature, tunneling is highly anisotropic, we determine the
transmission probabilities for the central and sidebands as the incident angle
of the electron beam is changed . Furthermore, we investigate how the
transmission probabilities change as the width, amplitude and frequency of the
oscillating barrier is changed. An interesting result of our study is that
perfect transmission for normal incidence that has been reported for a static
barrier persists for the oscillating barrier, manifestation of Klein tunneling
in a time harmonic potential.


title:
An Experimentally accessible geometric measure for entanglement in
  $N$-qubit pure states

abstract:
  We present a multipartite entanglement measure for $N$-qubit pure states,
using the norm of the correlation tensor which occurs in the Bloch
representation of the state. We compute this measure for several important
classes of $N$-qubit pure states such as GHZ states, W states and their
superpositions. We compute this measure for interesting applications like one
dimensional Heisenberg antiferromagnet. We use this measure to follow the
entanglement dynamics of Grover's algorithm. We prove that this measure
possesses almost all the properties expected of a good entanglement measure,
including monotonicity. Finally, we extend this measure to $N$-qubit mixed
states via convex roof construction and establish its various properties,
including its monotonicity. We also introduce a related measure which has all
properties of the above measure and is also additive.


title: Study of the suppressed B meson decay B^- -> D K^-, D -> K^+ \pi^-

abstract:
  We report a study of the suppressed B meson decay B^- -> D K^- followed by D
-> K^+ \pi^-, where D indicates a D^0 or \bar{D}^0 state. The two decay paths
interfere and provide information on the CP-violating angle \phi_3. We use a
data sample containing 657 x 10^6 B\bar{B} pairs recorded at the \Upsilon(4S)
resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- storage
ring. We do not find significant evidence for the mode B^- -> D K^-, D -> K^+
\pi^-, and set an upper limit of r_B < 0.19, where r_B is the magnitude of the
ratio of amplitudes |A(B^- -> \bar{D}^0 K^-)/A(B^- -> D^0 K^-)|. The decay B^-
-> D \pi^-, D -> K^+ \pi^- is also analyzed as a reference, for which we
observe a signal with 6.6\sigma significance, and measure the charge asymmetry
A_{D\pi} to be -0.02^{+0.15}_{-0.16}(stat) \pm 0.04(syst). In addition, the
ratio B(B^- -> D^0 K^-)/B(B^- -> D^0 \pi^-) is measured to be [6.77 \pm
0.23(stat) \pm 0.30(syst)] x 10^{-2}.


title: Cross-correlation of long-range correlated series

abstract:
  A method for estimating the cross-correlation $C_{xy}(\tau)$ of long-range
correlated series $x(t)$ and $y(t)$, at varying lags $\tau$ and scales $n$, is
proposed. For fractional Brownian motions with Hurst exponents $H_1$ and $H_2$,
the asymptotic expression of $C_{xy}(\tau)$ depends only on the lag $\tau$
(wide-sense stationarity) and scales as a power of $n$ with exponent
${H_1+H_2}$ for $\tau\to 0$. The method is illustrated on (i) financial series,
to show the leverage effect; (ii) genomic sequences, to estimate the
correlations between structural parameters along the chromosomes.


title: Coulomb dissociation of 9Li and the rate of the 8Li(n,g)9Li reaction

abstract:
  We calculate the Coulomb dissociation of 9Li on Pb and U targets at 28.5
MeV/A beam energy within a finite range distorted wave Born approximation
formalism of the breakup reactions. Invoking the principle of detailed balance,
these cross sections are used to determine the excitation function and
subsequently the rate of the radiative capture reaction 8Li(n,g)9Li at
astrophysical energies. Our method is free from the uncertainties associated
with the multipole strength distributions of the 9Li nucleus. The rate of this
reaction at a temperature of 10^9K is found to be about 2900 cm^3 mole^{-1}
s^{-1}.