title: Probing hypernuclei at PANDA and at MAMI-C

abstract:
  Spectroscopy of Lambda hypernuclei has recently become one of the most
valuable tools for the experimental investigation of strangeness nuclear
physics. Several new approached are being pursued currently: In Mainz, the
Microtron MAMI has been upgraded to 1.5 GeV electron beam energy and will be
used to produce strange hadronic systems in the near future. The KaoS
spectrometer is being installed for large acceptance, high resolution
strangeness reaction spectroscopy at the existing spectrometer facility.
  The Mainz hypernuclei research programme will be complemented by experiments
on multi-strange systems at the planned FAIR facility at GSI. The gamma-ray
spectroscopy of double Lambda hypernuclei produced via Xi-bar Xi pair
production is one of the four main topics which will be addressed by the PANDA
Collaboration. In this paper the status of the planned experiments and the
future prospects are presented.


title:
Non-radiative exciton energy transfer in hybrid organic-inorganic
  heterostructures

abstract:
  Non-radiative optical energy transfer from a GaAs quantum well to a thin
overlayer of an infrared organic semiconductor dye is unambiguously
demonstrated. The dynamics of exciton transfer are studied in the time-domain
using pump-probe spectroscopy at the donor site and fluorescence spectroscopy
at the acceptor site. The effect is observed as simultaneous increase of the
population decay rate at the donor and of the rise time of optical emission at
the acceptor sites. The hybrid configuration under investigation provides an
alternative non-radiative, non-contact pumping route to electrical carrier
injection that overcomes the losses imposed by the associated low carrier
mobility of organic emitters.


title:
Investigation of photoneutron reactions close to and above the neutron
  emission threshold in the rare earth region

abstract:
  We have investigated the photoneutron cross section of the isotopes
$^{148,150}$Nd, $^{154}$Sm, and $^{154,160}$Gd close to the neutron emission
threshold in photoactivation experiments at the Darmstadt superconducting
electron linear accelerator S-DALINAC. Naturally composed targets were
activated with a high-intensity bremsstrahlung beam at various energies and the
reaction yields have been determined by measuring the activity of the produced
radioactive isotopes with HPGe detectors. The results are compared to two
different statistical model calculations.


title: The Near-Star Environment: Spectropolarimetry of Herbig Ae/Be Stars

abstract:
  The near-star environment around young stars is very dynamic with winds,
disks, and outflows. These processes are involved in star and planet formation,
and influence the formation and habitability of planets around host stars. Even
for the closest young stars, this will not be imaged even after the completion
of the next generation of telescopes decades from now and other proxies must be
used. The polarization of light across individual spectral lines is such a
proxy that contains information about the geometry and density of circumstellar
material on these small spatial scales. We have recently built a
high-resolution spectropolarimeter (R~13000 to 50000) for the HiVIS
spectrograph on the 3.67m AEOS telescope. We used this instrument to monitor
several young intermediate-mass stars over many nights. These observations show
clear spectropolarimetric signatures typically centered on absorptive
components of the spectral lines, with some signatures variable in time. The
survey also confirms the large spectroscopic variability in these stars on
timescales of minutes to months, and shows the dyamic bullets and streamers in
the stellar winds. These observations were largely inconsistent with the
traditional scattering models and inspired the development of a new explanation
of their polarization, based on optical-pumping, that has the potential to
provide direct measurements of the circumstellar gas properties.


title: Generalized D-Forms Have No Spurious Creases

abstract:
  A convex surface that is flat everywhere but on finitely many smooth curves
(or "seams") and points is a seam form. We show that the only creases through
the flat components of a seam form are either between vertices or tangent to
the seams. As corollaries we resolve open problems about certain special seam
forms: the flat components of a D-form have no creases at all, and the flat
component of a pita-form has at most one crease, between the seam's endpoints.


title: Three- and Four-jet Production at Low x at HERA

abstract:
  Three- and four-jet production is measured in deep-inelastic $ep$ scattering
at low $x$ and $Q^2$ with the H1 detector using an integrated luminosity of
$44{.}2 {\rm pb}^{-1}$. Several phase space regions are selected for the
three-jet analysis in order to study the underlying parton dynamics from global
topologies to the more restrictive regions of forward jets close to the proton
direction. The measurements of cross sections for events with at least three
jets are compared to fixed order QCD predictions of ${\mathcal{O}}(\alpha_{\rm
s}^2)$ and ${\mathcal{O}}(\alpha_{\rm s}^3) $ and with Monte Carlo simulation
programs where higher order effects are approximated by parton showers. A good
overall description is provided by the ${\mathcal{O}}(\alpha_{\rm s}^3) $
calculation. Too few events are predicted at the lowest $x \sim 10^{-4}$,
especially for topologies with two forward jets. This hints to large
contributions at low $x$ from initial state radiation of gluons close to the
proton direction and unordered in transverse momentum. The Monte Carlo program
in which gluon radiation is generated by the colour dipole model gives a good
description of both the three- and the four-jet data in absolute normalisation
and shape.


title: Quasars and the Hubble Relation

abstract:
  If active galaxies are defined as extragalactic objects with appreciably non
thermal spectra then a continuity exists in redshift from the highest redshift
quasars to low redshift Seyferts, AGNs and allied galaxies.
  Evidence is discussed for this sequence to be an evolutionary track with
objects evolving from high to low intrinsic redshift with time. At the end of
this evolution the objects are nearly the same age as our own galaxy and they
come to rest on the traditional Hubble relation.


title:
Expressions of algebra elements and transcendental noncommutative
  calculus

abstract:
  Ideas from deformation quantization are applied to deform the expression of
elements of an algebra. Extending these ideas to certain transcendental
elements implies that $\frac{1}{i\h}uv$ in the Weyl algebra is naturally viewed
as an indeterminate living in a discrete set $\mathbb{N}{+}{1/2}$ {\it or}
${-}(\mathbb{N}{+}{1/2})$ . This may yield a more mathematical understanding of
Dirac's positron theory.


title: The birth of a cut in unitary random matrix ensembles

abstract:
  We study unitary random matrix ensembles in the critical regime where a new
cut arises away from the original spectrum. We perform a double scaling limit
where the size of the matrices tends to infinity, but in such a way that only a
bounded number of eigenvalues is expected in the newborn cut. It turns out that
limits of the eigenvalue correlation kernel are given by Hermite kernels
corresponding to a finite size Gaussian Unitary Ensemble (GUE). When modifying
the double scaling limit slightly, we observe a remarkable transition each time
the new cut picks up an additional eigenvalue, leading to a limiting kernel
interpolating between GUE-kernels for matrices of size k and size k+1. We prove
our results using the Riemann-Hilbert approach.


title: Transport properties of graphene nanoribbon heterostructures

abstract:
  We study the electronic and transport properties of heterostructures formed
by armchair graphene nanoribbons with intersections of finite length. We
describe the system by a tight-binding model and calculate the density of
states and the conductance within the Green's function formalism based on
real-space renormalization techniques. We show the apparition of interface
states and bound states in the continuum which present a strong dependence of
the heterostructure geometry. We investigate the effects on the conductance of
an external perturbation applied on the edges atoms of the intersection region.


title:
Intermittency transition to generalized synchronization in coupled
  time-delay systems

abstract:
  In this paper, we report the nature of transition to generalized
synchronization (GS) in a system of two coupled scalar piecewise linear
time-delay systems using the auxiliary system approach. We demonstrate that the
transition to GS occurs via on-off intermittency route and also it exhibits
characteristically distinct behaviors for different coupling configurations. In
particular, the intermittency transition occurs in a rather broad range of
coupling strength for error feedback coupling configuration and in a narrow
range of coupling strength for direct feedback coupling configuration. It is
also shown that the intermittent dynamics displays periodic bursts of period
equal to the delay time of the response system in the former case, while they
occur in random time intervals of finite duration in the latter case. The
robustness of these transitions with system parameters and delay times has also
been studied for both linear and nonlinear coupling configurations. The results
are corroborated analytically by suitable stability conditions for
asymptotically stable synchronized states and numerically by the probability of
synchronization and by the transition of \emph{sub}Lyapunov exponents of the
coupled time-delay systems. We have also indicated the reason behind these
distinct transitions by referring to unstable periodic orbit theory of
intermittency synchronization in low-dimensional systems.


title: Map of Discrete System into Continuous

abstract:
  Continuous limits of discrete systems with long-range interactions are
considered. The map of discrete models into continuous medium models is
defined. A wide class of long-range interactions that give the fractional
equations in the continuous limit is discussed. The one-dimensional systems of
coupled oscillators for this type of long-range interactions are considered.
The discrete equations of motion are mapped into the continuum equation with
the Riesz fractional derivative.


title: A few steps more towards NPT bound entanglement

abstract:
  We consider the problem of existence of bound entangled states with
non-positive partial transpose (NPT). As one knows, existence of such states
would in particular imply nonadditivity of distillable entanglement. Moreover
it would rule out a simple mathematical description of the set of distillable
states. Distillability is equivalent to so called n-copy distillability for
some n. We consider a particular state, known to be 1-copy nondistillable,
which is supposed to be bound entangled. We study the problem of its two-copy
distillability, which boils down to show that maximal overlap of some projector
Q with Schmidt rank two states does not exceed 1/2. Such property we call the
the half-property. We first show that the maximum overlap can be attained on
vectors that are not of the simple product form with respect to cut between two
copies. We then attack the problem in twofold way: a) prove the half-property
for some classes of Schmidt rank two states b) bound the required overlap from
above for all Schmidt rank two states. We have succeeded to prove the
half-property for wide classes of states, and to bound the overlap from above
by c<3/4. Moreover, we translate the problem into the following matrix analysis
problem: bound the sum of the squares of the two largest singular values of
matrix A \otimes I + I \otimes B with A,B traceless 4x4 matrices, and Tr
A^\dagger A + Tr B^\dagger B = 1/4.


title:
Measurement of surface alpha-acrivity of different samples with ion
  pulse ionization chamber

abstract:
  The construction of an ion pulse ionization chamber aimed at measuring
ultra-low levels of surface alpha-activity of different samples is described.
The results of measurement carried out with alpha-source and copper samples and
light-reflecting film VM2000 are presented.


title: A Biologically Inspired Classifier

abstract:
  We present a method for measuring the distance among records based on the
correlations of data stored in the corresponding database entries. The original
method (F. Bagnoli, A. Berrones and F. Franci. Physica A 332 (2004) 509-518)
was formulated in the context of opinion formation. The opinions expressed over
a set of topic originate a ``knowledge network'' among individuals, where two
individuals are nearer the more similar their expressed opinions are. Assuming
that individuals' opinions are stored in a database, the authors show that it
is possible to anticipate an opinion using the correlations in the database.
This corresponds to approximating the overlap between the tastes of two
individuals with the correlations of their expressed opinions.
  In this paper we extend this model to nonlinear matching functions, inspired
by biological problems such as microarray (probe-sample pairing). We
investigate numerically the error between the correlation and the overlap
matrix for eight sequences of reference with random probes. Results show that
this method is particularly robust for detecting similarities in the presence
of translocations.


title: Modeling Protein Contact Networks

abstract:
  Proteins are an important class of biomolecules that serve as essential
building blocks of the cells. Their three-dimensional structures are
responsible for their functions. In this thesis we have investigated the
protein structures using a network theoretical approach. While doing so we used
a coarse-grained method, viz., complex network analysis. We model protein
structures at two length scales as Protein Contact Networks (PCN) and as
Long-range Interaction Networks (LINs). We found that proteins by virtue of
being characterised by high amount of clustering, are small-world networks.
Apart from the small-world nature, we found that proteins have another general
property, viz., assortativity. This is an interesting and exceptional finding
as all other complex networks (except for social networks) are known to be
disassortative. Importantly, we could identify one of the major topological
determinant of assortativity by building appropriate controls.


title:
A remark on the mean-field dynamics of many-body bosonic systems with
  random interactions

abstract:
  The mean-field limit for the dynamics of bosons with random interactions is
rigorously studied. It is shown that, for interactions that are almost-surely
bounded, the many-body quantum evolution can be replaced in the mean-field
limit by a single particle nonlinear evolution that is described by the Hartree
equation. This is an Egorov-type theorem for many-body quantum systems with
random interactions.


title:
A System for Distributed Mechanisms: Design, Implementation and
  Applications

abstract:
  We describe here a structured system for distributed mechanism design
appropriate for both Intranet and Internet applications. In our approach the
players dynamically form a network in which they know neither their neighbours
nor the size of the network and interact to jointly take decisions. The only
assumption concerning the underlying communication layer is that for each pair
of processes there is a path of neighbours connecting them. This allows us to
deal with arbitrary network topologies.
  We also discuss the implementation of this system which consists of a
sequence of layers. The lower layers deal with the operations that implement
the basic primitives of distributed computing, namely low level communication
and distributed termination, while the upper layers use these primitives to
implement high level communication among players, including broadcasting and
multicasting, and distributed decision making.
  This yields a highly flexible distributed system whose specific applications
are realized as instances of its top layer. This design is implemented in Java.
  The system supports at various levels fault-tolerance and includes a
provision for distributed policing the purpose of which is to exclude
`dishonest' players. Also, it can be used for repeated creation of dynamically
formed networks of players interested in a joint decision making implemented by
means of a tax-based mechanism. We illustrate its flexibility by discussing a
number of implemented examples.


title:
Newton-type Methods for REML Estimation in Genetic Analysis of
  Quantitative Traits

abstract:
  Robust and efficient optimization methods for variance component estimation
using Restricted Maximum Likelihood (REML) models for genetic mapping of
quantitative traits are considered. We show that the standard Newton-AI scheme
may fail when the optimum is located at one of the constraint boundaries, and
we introduce different approaches to remedy this by taking the constraints into
account. We approximate the Hessian of the objective function using the average
information matrix and also by using an inverse BFGS formula. The robustness
and efficiency is evaluated for problems derived from two experimental data
from the same animal populations.


title: Modelling individual globular clusters

abstract:
  Astronomers have constructed models of globular clusters for over 100 years.
These models mainly fall into two categories: (i) static models, such as King's
model and its variants, and (ii) evolutionary models. Most attention has been
given to static models, which are used to estimate mass-to-light ratios and
mass segregation, and to combine data from proper motions and radial
velocities. Evolutionary models have been developed for a few objects using the
gaseous model, the Fokker-Planck model, Monte Carlo models and N-body models.
These models have had a significant role in the search for massive black holes
in globular clusters, for example.
  In this presentation the problems associated with these various techniques
will be summarised, and then we shall describe new work with Giersz's Monte
Carlo code, which has been enhanced recently to include the stellar evolution
of single and binary stars. We describe in particular recent attempts to model
the nearby globular cluster M4, including predictions on the spatial
distribution of binary stars and their semi-major axis distribution, to
illustrate the effects of about 12 Gyr of dynamical evolution. We also discuss
work on an approximate way of predicting the "initial" conditions for such
modelling.


title: Spectra of graphs and semi-conducting polymers

abstract:
  We study the band gap in some semi-conducting polymers with two models:
H\"uckel molecular orbital theory and the so-called free electron model. The
two models are directly related to spectral theory on combinatorial and metric
graphs.


title:
Neutrino mass constraint from CMB and its degeneracy with other
  cosmological parameters

abstract:
  We show that the cosmic microwave background (CMB) data of WMAP can give
subelectronvolt limit on the neutrino mass: m_nu < 0.63 eV (95% CL). We also
investigate its degeneracy with other cosmological parameters. In particular,
we show the Hubble constant derived from the WMAP data decreases considerably
when the neutrino mass is a few times 0.1 eV.


title: The VPN Tree Routing Conjecture for Outerplanar Networks

abstract:
  The VPN Tree Routing Conjecture is a conjecture about the Virtual Private
Network Design problem. It states that the symmetric version of the problem
always has an optimum solution which has a tree-like structure. In recent work,
Hurkens, Keijsper and Stougie (Proc. IPCO XI, 2005; SIAM J. Discrete Math.,
2007) have shown that the conjecture holds when the network is a ring. A
shorter proof of the VPN Conjecture for rings was found a few months ago by
Grandoni, Kaibel, Oriolo and Skutella (to appear in Oper. Res. Lett., 2008). In
their paper, Grandoni et al. introduce another conjecture, called the Pyramidal
Routing Conjecture (or simply PR Conjecture), which implies the VPN Conjecture.
Here we consider a strengthened version of the PR Conjecture. First we
establish several general tools which can be applied in arbitrary networks.
Then we use them to prove that outerplanar networks satisfy the PR Conjecture.


title: Renewal equations for option pricing

abstract:
  In this paper we will develop a methodology for obtaining pricing expressions
for financial instruments whose underlying asset can be described through a
simple continuous-time random walk (CTRW) market model. Our approach is very
natural to the issue because it is based in the use of renewal equations, and
therefore it enhances the potential use of CTRW techniques in finance. We solve
these equations for typical contract specifications, in a particular but
exemplifying case. We also show how a formal general solution can be found for
more exotic derivatives, and we compare prices for alternative models of the
underlying. Finally, we recover the celebrated results for the Wiener process
under certain limits.


title: Generalized parton distributions and the structure of the nucleon

abstract:
  Generalized parton distributions have been introduced in recent years as a
suitable theoretical tool to study the structure of the nucleon. Unifying the
concepts of parton distributions and hadronic form factors, they provide a
comprehensive framework for describing the quark and gluon structure of the
nucleon. In this review their formal properties and modeling are discussed,
summarizing the most recent developments in the phenomenological description of
these functions. The status of available data is also presented.


title: Fermion Masses from SO(10) Hermitian Matrices

abstract:
  Masses of fermions in the SO(10) 16-plet are constructed using only the 10,
120 and 126 scalar multiplets. The mass matrices are restricted to be hermitian
and the theory is constructed to have certain assumed quark masses, charged
lepton masses and CKM matrix in accord with data. The remaining free parameters
are found by fitting to light neutrino masses and MSN matrices result as
predictions.


title:
Observability of the virialization phase of spheroidal galaxies with
  radio arrays

abstract:
  In the standard galaxy formation scenario plasma clouds with a high thermal
energy content must exist at high redshifts since the proto-galactic gas is
shock heated to the virial temperature, and extensive cooling, leading to
efficient star formation, must await the collapse of massive halos (as
indicated by the massive body of evidence, referred to as "downsizing").
Massive plasma clouds are potentially observable through the thermal and
kinetic Sunyaev-Zel'dovich effects and their free-free emission. We find that
the detection of substantial numbers of galaxy-scale thermal SZ signals is
achievable by blind surveys with next generation radio telescope arrays such as
EVLA, ALMA and SKA. This population is even detectable with the 10% SKA, and
wide field of view options at high frequency on any of these arrays would
greatly increase survey speed. An analysis of confusion effects and of the
contamination by radio and dust emissions shows that the optimal frequencies
are those in the range 10-35 GHz. Predictions for the redshift distributions of
detected sources are also worked out.


title:
Comparing Effective-One-Body gravitational waveforms to accurate
  numerical data

abstract:
  We continue the program of constructing, within the Effective-One-Body (EOB)
approach, high accuracy, faithful analytic waveforms describing the
gravitational wave signal emitted by inspiralling and coalescing binary black
holes (BHs). We present the comparable-mass version of a new, resummed
3PN-accurate EOB quadrupolar waveform recently introduced in the
small-mass-ratio limit. We compare the phase and the amplitude of this waveform
to the recently published results of a high-accuracy numerical relativity (NR)
simulation of 15 orbits of an inspiralling equal-mass binary BHs system
performed by the Caltech-Cornell group. We find a remarkable agreement, both in
phase and in amplitude, between the new EOB waveform and the published
numerical data. More precisely: (i) in the gravitational wave (GW) frequency
domain $M\omega <0.08$ where the phase of one of the non-resummed ``Taylor
approximant'' (T4) waveform matches well with the numerical relativity one, we
find that the EOB phase fares as well, while (ii) for higher GW frequencies,
$0.08<M\omega\lesssim 0.14$, where the TaylorT4 approximant starts to
significantly diverge from the NR phase, we show that the EOB phase continues
to match well the NR one. We further propose various methods of tuning the two
inspiral flexibility parameters, $a_5$ and $v_{\rm pole}$, of the EOB waveform
so as to ``best fit'' EOB predictions to numerical data. We find that the
maximal dephasing between EOB and NR can then be reduced below $10^{-3}$ GW
cycles over the entire span (30 GW cycles) of the simulation. Our resummed EOB
amplitude agrees much better with the NR one than any of the previously
considered non-resummed, post-Newtonian one.


title: Theoretical models in the Virtual Observatory

abstract:
  Although full interoperativity between theoretical and observational data in
the framework of the Virtual Observatory would be a very desirable achievement,
the current status of VO offers few approaches to handle theoretical models.
TSAP (Theoretical Spectra Access Protocol) has been proposed as a tool to fill
this void, providing a simple scheme to easily operate with th is kind of data.
TSAP is useful not only for synthetic spectra but also for other types of
theoretical data. As an example we show an Isochrone and Evolutionary Tracks
server using TSAP. Finally, we pay special attention to the correct treatment
of the credits an important issue in the field of theoretical models.


title: Mass loss and supernova progenitors

abstract:
  We first discuss the mass range of type IIP SN progenitors and how the upper
and lower limits impose interesting constraints on stellar evolution. Then we
discuss the possible implications of two SNe, 2002ap and 2006jc, for Wolf-Rayet
star mass-loss rates and long Gamma-ray bursts.


title:
Statistical properties of extragalactic sources in the New Extragalactic
  WMAP Point Source (NEWPS) catalogue

abstract:
  We present results on spectral index distributions, number counts, redshift
distribution and other general statistical properties of extragalactic point
sources in the NEWPS5 sample L\'opez-Caniego et al. (2007). The flux
calibrations at all the WMAP channels have been reassessed both by comparison
with ground based observations and through estimates of the effective beam
areas. The two methods yield consistent statistical correction factors. A
search of the NED has yielded optical identifications for 89% of sources in the
complete sub-sample of 252 sources with S/N>5 and S>1.1 Jy at 23 GHz; 5 sources
turned out to be Galactic and were removed. The NED also yielded redshifts for
92% of the extragalactic sources at |b|>10deg. Their distribution was compared
with model predictions; the agreement is generally good but a possible
discrepancy is noted. Using the 5 GHz fluxes from the GB6 or PMN surveys, we
find that 76% of the 191 extragalactic sources with S_23GHz>1.3,Jy can be
classified as flat-spectrum sources between 5 and 23 GHz. A spectral steepening
is observed at higher frequencies: only 59% of our sources are still
flat-spectrum sources between 23 and 61 GHz and the average spectral indexes
steepen from <alpha_5^23>= 0.01\pm 0.03 to <alpha_41^61>= 0.37\pm 0.03. We
think, however, that the difference may be due to a selection effect. The
source number counts have a close to Euclidean slope and are in good agreement
with the predictions of the cosmological evolution model by De Zotti et al.
(2005). The observed spectral index distributions were exploited to get
model-independent extrapolations of counts to higher frequencies. The risks of
such operations are discussed and reasons of discrepancies with other recent
estimates are clarified.


title: Prompt GRB emission from gradual energy dissipation

abstract:
  I calculate the emission expected from a Poynting-flux-dominated gamma-ray
burst (GRB) flow in which energy is dissipated gradually by magnetic
reconnection. In this picture, the energy of the radiating particles is
determined by heating and cooling balance (slow heating model). Detailed
radiative transfer calculations show that, at Thomson optical depths of order
of unity, the dominant radiative process is inverse Compton scattering.
Synchrotron-self-absorbed emission and inverse Compton dominate in the Thomson
thin parts of the flow. The electrons stay thermal throughout the dissipation
region because of Coulomb collisions (Thomson thick part of the flow) and
exchange of synchrotron photons (Thomson thin part). The resulting spectrum
naturally explains the observed sub-MeV break of the GRB emission and the
spectral slopes above and below the break. The model predicts that the
gamma-ray power-law tail has a high-energy cutoff typically in the ~0.1-1 GeV
energy range that should be observable with {\it GLAST}. The model also
predicts a prompt emission component in the optical and UV associated with the
GeV emission. Observations of the prompt emission of GRB 061121 that cover the
energy range from the optical to ~1 MeV are explained by the model.


title: Delay equations driven by rough paths

abstract:
  In this article, we illustrate the flexibility of the algebraic integration
formalism introduced by M. Gubinelli (2004), by establishing an existence and
uniqueness result for delay equations driven by rough paths. We then apply our
results to the case where the driving path is a fractional Brownian motion with
Hurst parameter H>1/3.


title:
Erratum: Initial fields and instability in the classical model of the
  heavy-ion collision

abstract:
  We correct a mistake in the analytical expression for the energy density
given in Phys. Rev. C76, 021902 (2007) [arXiv:0704.3625 [hep-ph]]. The
expression should be multiplied by 16. One question then arises; how could it
be possible to explain this difference between the analytical and numerical
results in the same model if both are correct? We find a subtle problem in the
treatment of the randomness of the color source along the longitudinal
direction and the treatment of the longitudinal extent of the color source.


title: The chiral condensate in a constant electromagnetic field at O(p^6)

abstract:
  We examine the shift in the chiral condensate due to a constant
electromagnetic field at ${\cal O}(p^6)$ using SU(2) chiral perturbation theory
and a realistic $M_\pi = 140 \textrm{MeV}$. We find that this value differs
significantly from the value calculated using $M_\pi = 0$, while the magnitude
of the two-loop correction is unclear due to the uncertainty in the
experimentally determined value of the relevant ${\cal L}_6$ LEC.


title:
Higher Moments of Heavy Quark Correlators in the Low Energy Limit at
  O(alpha_s^2)

abstract:
  We present the first 30 moments of the low energy expansions of the vector,
axial-vector, scalar and pseudo-scalar heavy quark correlation functions at
three-loop order, including the singlet contribution which appears for the
first time at three loops. In addition we compare the behavior of the moments
for large n with the prediction from threshold calculations.


title:
Comparative analysis of spectra of the background of the proportional
  counter filled with Kr, enriched in Kr-78, and with Kr of natural content

abstract:
  The results of the experiment searching for 2K-capture with large
low-background proportional counter are presented. The comparison of spectra of
the background of the proportional counter filled with Kr enriched in $^{78}$Kr
(8400 hr) and with natural Kr (3039 hr) is given. A new limit on the half-life
of $^{78}$Kr with regard to 2K-capture, T$_{1/2}\geq2.0\cdot10^{21}$ yrs (95%
C.L.) has been obtained.


title: Functionally Graded Media

abstract:
  The notions of uniformity and homogeneity of elastic materials are reviewed
in terms of Lie groupoids and frame bundles. This framework is also extended to
consider the case Functionally Graded Media, which allows us to obtain some
homogeneity conditions.


title: Strangeness in Relativistic Astrophysics

abstract:
  In these lecture notes, the role of strangeness in relativistic astrophysics
of compact stars is addressed. The appearance of strange particles, as
hyperons, kaons, and strange quarks, in the core of compact stars is examined
and common features as well as differences are presented. Impacts on the global
properties of compact stars and signals of the presence of exotic matter are
outlined for the various strange phases which can appear in the interior at
high densities.


title: The 't Hooft vertex revisited

abstract:
  In 1976 't Hooft introduced an elegant approach towards understanding the
physical consequences of the topological structures that appear in non-Abelian
gauge theories. These effects are concisely summarized in terms of an effective
multi-fermion interaction. These old arguments provide a link between a variety
of recent and sometimes controversial ideas including discrete chiral
symmetries appearing in some models for unification, ambiguities in the
definition of quark masses, and flaws with some simulation algorithms in
lattice gauge theory.


title: Extensive nonadditive entropy in quantum spin chains

abstract:
  We present details on a physical realization, in a many-body Hamiltonian
system, of the abstract probabilistic structure recently exhibited by
Gell-Mann, Sato and one of us (C.T.), that the nonadditive entropy $S_q=k [1-
Tr \hat{\rho}^q]/[q-1]$ ($\hat{\rho}\equiv$ density matrix; $S_1=-k Tr
\hat{\rho} \ln \hat{\rho}$) can conform, for an anomalous value of q (i.e., q
not equal to 1), to the classical thermodynamical requirement for the entropy
to be extensive. Moreover, we find that the entropic index q provides a tool to
characterize both universal and nonuniversal aspects in quantum phase
transitions (e.g., for a L-sized block of the Ising ferromagnetic chain at its
T=0 critical transverse field, we obtain
$\lim_{L\to\infty}S_{\sqrt{37}-6}(L)/L=3.56 \pm 0.03$). The present results
suggest a new and powerful approach to measure entanglement in quantum
many-body systems. At the light of these results, and similar ones for a d=2
Bosonic system discussed by us elsewhere, we conjecture that, for blocks of
linear size L of a large class of Fermionic and Bosonic d-dimensional many-body
Hamiltonians with short-range interaction at T=0, we have that the additive
entropy $S_1(L) \propto [L^{d-1}-1]/(d-1)$ (i.e., $ \ln L$ for $d=1$, and $
L^{d-1}$ for d>1), hence it is not extensive, whereas, for anomalous values of
the index q, we have that the nonadditive entropy $S_q(L)\propto L^d$ ($\forall
d$), i.e., it is extensive. The present discussion neatly illustrates that
entropic additivity and entropic extensivity are quite different properties,
even if they essentially coincide in the presence of short-range correlations.


title:
Multiuser MIMO Achievable Rates with Downlink Training and Channel State
  Feedback

abstract:
  We consider a MIMO fading broadcast channel and compute achievable ergodic
rates when channel state information is acquired at the receivers via downlink
training and it is provided to the transmitter by channel state feedback.
Unquantized (analog) and quantized (digital) channel state feedback schemes are
analyzed and compared under various assumptions. Digital feedback is shown to
be potentially superior when the feedback channel uses per channel state
coefficient is larger than 1. Also, we show that by proper design of the
digital feedback link, errors in the feedback have a minor effect even if
simple uncoded modulation is used on the feedback channel. We discuss first the
case of an unfaded AWGN feedback channel with orthogonal access and then the
case of fading MIMO multi-access (MIMO-MAC). We show that by exploiting the
MIMO-MAC nature of the uplink channel, a much better scaling of the feedback
channel resource with the number of base station antennas can be achieved.
Finally, for the case of delayed feedback, we show that in the realistic case
where the fading process has (normalized) maximum Doppler frequency shift 0 < F
< 1/2, a fraction 1 - 2F of the optimal multiplexing gain is achievable. The
general conclusion of this work is that very significant downlink throughput is
achievable with simple and efficient channel state feedback, provided that the
feedback link is properly designed.


title: Kernel method for nonlinear Granger causality

abstract:
  Important information on the structure of complex systems, consisting of more
than one component, can be obtained by measuring to which extent the individual
components exchange information among each other. Such knowledge is needed to
reach a deeper comprehension of phenomena ranging from turbulent fluids to
neural networks, as well as complex physiological signals. The linear Granger
approach, to detect cause-effect relationships between time series, has emerged
in recent years as a leading statistical technique to accomplish this task.
Here we generalize Granger causality to the nonlinear case using the theory of
reproducing kernel Hilbert spaces. Our method performs linear Granger causality
in the feature space of suitable kernel functions, assuming arbitrary degree of
nonlinearity. We develop a new strategy to cope with the problem of
overfitting, based on the geometry of reproducing kernel Hilbert spaces.
Applications to coupled chaotic maps and physiological data sets are presented.


title:
Anisotropic harmonic oscillator, non-commutative Landau problem and
  exotic Newton-Hooke symmetry

abstract:
  We investigate the planar anisotropic harmonic oscillator with explicit
rotational symmetry as a particle model with non-commutative coordinates. It
includes the exotic Newton-Hooke particle and the non-commutative Landau
problem as special, isotropic and maximally anisotropic, cases. The system is
described by the same (2+1)-dimensional exotic Newton-Hooke symmetry as in the
isotropic case, and develops three different phases depending on the values of
the two central charges. The special cases of the exotic Newton-Hooke particle
and non-commutative Landau problem are shown to be characterized by additional,
so(3) or so(2,1) Lie symmetry, which reflects their peculiar spectral
properties.


title:
Temperature dependence of the gain profile for THz quantum cascade
  lasers

abstract:
  We study the rapid decrease of peak gain in resonant-phonon THz Quantum
Cascade Lasers with increasing temperature. The effect of various microscopic
scattering processes on the gain profile as a function of temperature is
discussed. We argue that increased broadening, primarily due to increased
impurity scattering, and not diminishing population inversion, is the main
reason for the reduction of peak gain.


title: Cosmological model with interactions in the dark sector

abstract:
  A cosmological model is proposed for the current Universe consisted of
non-interacting baryonic matter and interacting dark components. The dark
energy and dark matter are coupled through their effective barotropic indexes,
which are considered as functions of the ratio between their energy densities.
It is investigated two cases where the ratio is asymptotically stable and their
parameters are adjusted by considering best fits to Hubble function data. It is
shown that the deceleration parameter, the densities parameters, and the
luminosity distance have the correct behavior which is expected for a viable
present scenario of the Universe.


title:
Comparing the observational instability regions for pulsating pre-main
  sequence and classical $\delta$ Scuti stars

abstract:
  A comparison of the hot and cool boundaries of the classical instability
strip with observations has been an important test for stellar structure and
evolution models of post- and main sequence stars. Over the last few years, the
number of pulsating pre-main sequence (PMS) stars has increased significantly:
36 PMS pulsators and candidates are known as of June 2007. This number allows
to investigate the location of the empirical PMS instability region and to
compare its boundaries to those of the classical (post- and main sequence)
instability strip. Due to the structural differences of PMS and (post-)main
sequence stars, the frequency spacings for nonradial modes will be measurably
different, thus challenging asteroseismology as a diagnostic tool.


title:
Surface Plasmon mediated near-field imaging and optical addressing in
  nanoscience

abstract:
  We present an overview of recent progress in plasmonics. We focus our study
on the observation and excitation of surface plasmon polaritons (SPPs) with
optical near-field microscopy. We discuss in particular recent applications of
photon scanning tunnelling microscope (PSTM) for imaging of SPP propagating in
metal and dielectric wave guides. We show how near-field scanning optical
microscopy (NSOM) can be used to optically and actively address remotely
nano-objects such as quantum dots. Additionally we compare results obtained
with near-field microscopy to those obtained with other optical far-field
methods of analysis such as leakage radiation microscopy (LRM).


title: Neutrino spin rotation in dense matter and electromagnetic field

abstract:
  Exact solutions of the Dirac--Pauli equation for massive neutrino with
anomalous magnetic moment interacting with dense matter and strong
electromagnetic field are found. The complete system of neutrino wavefunctions,
which show spin rotation properties are obtained and their possible
applications are discussed.


title: Neutrino Physics and CP violation

abstract:
  We review some aspects of neutrino physics and CP violation both in the quark
and lepton sectors.


title: Coordinates, observables and symmetry in relativity

abstract:
  We investigate the interplay and connections between symmetry properties of
equations, the interpretation of coordinates, the construction of observables,
and the existence of physical relativity principles in spacetime theories.
Using the refined notion of an event as a ``point-coincidence'' between scalar
fields that completely characterise a spacetime model, we also propose a
natural generalisation of the relational local observables that does not
require the existence of four everywhere invertible scalar fields. The
collection of all point-coincidences forms in generic situations a
four-dimensional manifold, that is naturally identified with the physical
spacetime.


title: An information-theoretic analog of a result of Perelman

abstract:
  Each compact manifold M of finite dimension k is differentiable and supports
an intrinsic probability measure. There then exists a measurable transformation
of M to the k-dimensional "surface" of the (k+1)-dimensional ball.


title: Non-locality, Contextuality and Transition sets

abstract:
  We discuss quantum non-locality and contextuality using the notion of
transition sets. This approach provides a way to obtain a direct logical
contradiction with locality/non-contextuality in the EPRB gedanken experiment
as well as a clear graphical illustration of what violations of Bell
inequalities quantify. In particular, we show graphically how these violations
are related to measures of non-local transition sets. We also introduce a new
form of contextuality, {\em measurement ordering contextuality}, i.e. there
exists commuting operators $\hat{\mathcal{A}}$ and $\hat{\mathcal{B}}$ such
that the outcome for $\hat{\mathcal{A}}$ depends on whether we measured
$\hat{\mathcal{B}}$ before or after $\hat{\mathcal{A}}$. It is shown (excluding
retro-causal and/or conspiratorial theories) that any hidden variable theory
capable of reproducing the quantum statistics has to have this property. This
generalizes yet another feature of the hidden variable theory of deBroglie and
Bohm.


title:
New force replica exchange method and protein folding pathways probed by
  force-clamp technique

abstract:
  We have developed a new extended replica exchange method to study
thermodynamics of a system in the presence of external force. Our idea is based
on the exchange between different force replicas to accelerate the equilibrium
process. We have shown that the refolding pathways of single ubiquitin depend
on which terminus is fixed. If the N-end is fixed then the folding pathways are
different compared to the case when both termini are free, but fixing the
C-terminal does not change them. Surprisingly, we have found that the anchoring
terminal does not affect the pathways of individual secondary structures of
three-domain ubiquitin, indicating the important role of the multi-domain
construction. Therefore, force-clamp experiments, in which one end of a protein
is kept fixed, can probe the refolding pathways of a single free-end ubiquitin
if one uses either the poly-ubiquitin or a single domain with the C-terminus
anchored. However, it is shown that anchoring one end does not affect refolding
pathways of the titin domain I27, and the force-clamp spectroscopy is always
capable to predict folding sequencing of this protein. We have obtained the
reasonable estimate for unfolding barrier of ubiqutin. The linkage between
residue Lys48 and the C-terminal of ubiquitin is found to have the dramatic
effect on the location of the transition state along the end-to-end distance
reaction coordinate, but the multi-domain construction leaves the transition
state almost unchanged. We have found that the maximum force in the
force-extension profile from constant velocity force pulling simulations
depends on temperature nonlinearly. However, for some narrow temperature
interval this dependence becomes linear, as have been observed in recent
experiments.


title: Full-sky maps for gravitational lensing of the CMB

abstract:
  We use the large cosmological Millennium Simulation (MS) to construct the
first all-sky maps of the lensing potential and the deflection angle, aiming at
gravitational lensing of the CMB, with the goal of properly including
small-scale non-linearities and non-Gaussianity. Exploiting the Born
approximation, we implement a map-making procedure based on direct ray-tracing
through the gravitational potential of the MS. We stack the simulation box in
redshift shells up to $z\sim 11$, producing continuous all-sky maps with
arcminute angular resolution. A randomization scheme avoids repetition of
structures along the line of sight and structures larger than the MS box size
are added to supply the missing contribution of large-scale (LS) structures to
the lensing signal. The angular power spectra of the projected lensing
potential and the deflection-angle modulus agree quite well with semi-analytic
estimates on scales down to a few arcminutes, while we find a slight excess of
power on small scales, which we interpret as being due to non-linear clustering
in the MS. Our map-making procedure, combined with the LS adding technique, is
ideally suited for studying lensing of CMB anisotropies, for analyzing
cross-correlations with foreground structures, or other secondary CMB
anisotropies such as the Rees-Sciama effect.


title:
Structure of the Radio Source 3C 120 at 8.4 GHz from VLBA+ Observations
  in 2002

abstract:
  Maps of the radio source 3C 120 obtained from VLBA+ observations at 8.4 GHz
at five epochs in January - September 2002 are presented. The images were
reconstructed using the maximum entropy method and the Pulkovo VLBImager
software package for VLBI mapping. Apparent superluminal motions of the
brightest jet knots have been estimated. The speeds of jet knots decreases with
distance from the core, changing from 5.40+-0.48c $ to 2.00+-0.48c over 10 mas
(where c is the speed of light) for a Hubble constant of 65 km/s/Mpc. This can
be explained by interaction of the jet with the medium through which it
propagates.


title: Characterization of Piezoelectric Materials for Transducers

abstract:
  Review of techniques for characterizing piezoelectric/electrostrictive
material for transducer applications.


title:
Frame representations of quantum mechanics and the necessity of
  negativity in quasi-probability representations

abstract:
  Several finite dimensional quasi-probability representations of quantum
states have been proposed to study various problems in quantum information
theory and quantum foundations. These representations are often defined only on
restricted dimensions and their physical significance in contexts such as
drawing quantum-classical comparisons is limited by the non-uniqueness of the
particular representation. Here we show how the mathematical theory of frames
provides a unified formalism which accommodates all known quasi-probability
representations of finite dimensional quantum systems. Moreover, we show that
any quasi-probability representation satisfying two reasonable properties is
equivalent to a frame representation and then prove that any such
representation of quantum mechanics must exhibit either negativity or a
deformed probability calculus.


title:
Spontaneous breaking of translational invariance in non-commutative
  lambda phi^4 theory in two dimensions

abstract:
  The spontaneous breaking of of translational invariance in non-commutative
self-interacting scalar field theory in two dimensions is investigated by
effective action techniques. The analysis confirms the existence of the stripe
phase, already observed in lattice simulations, due to the non-local nature of
the non-commutative dynamics.


title: Leptonic D and D_s Decays near c-cbar Threshold

abstract:
  We present recent results from the CLEO Collaboration on leptonic decay rates
of $D$ and $D_s$ near $c\bar{c}$ production threshold. From these decay rates,
we extract the decay constants, f_D = (222.6+-16.7^{+2.8}_{-3.4}) MeV, f_Ds =
(274+-10+-5) MeV, and the ratio f_Ds/f_D = 1.23+-0.11+-0.03.


title: Self-induced oscillations in an optomechanical system

abstract:
  We have explored the nonlinear dynamics of an optomechanical system
consisting of an illuminated Fabry-Perot cavity, one of whose end-mirrors is
attached to a vibrating cantilever. Such a system can experience negative
light-induced damping and enter a regime of self-induced oscillations. We
present a systematic experimental and theoretical study of the ensuing
attractor diagram describing the nonlinear dynamics, in an experimental setup
where the oscillation amplitude becomes large, and the mirror motion is
influenced by several optical modes. A theory has been developed that yields
detailed quantitative agreement with experimental results. This includes the
observation of a regime where two mechanical modes of the cantilever are
excited simultaneously.


title: Electromagnetically induced transparency at high optical power

abstract:
  We observe electromagnetically induced transparency (EIT) in Rb vapor at
various optical intensities, starting from below saturation to several times
the saturation intensity. The observed Lorentzian width of the EIT signal is
very small. Solving the time dependant density matrix equation of motion with a
phenomenological decay constant, we find an expression suitable in explaining
the EIT signal. In this experimental observation and theoretical analysis
intensity of EIT signal and its Lorentzian width increases with Rabi frequency
of optical field.


title: Wide range and highly sensitive atomic magnetometry with Rb vapor

abstract:
  We have developed a technique in which Rb atomic response to weak magnetic
field is high and an efficient rotation of linearly polarized laser beam
results in efficient magnetometry. 85Rb isotope has been used for the
magnetometry in an ordinary vapor cell without any paraffin coating to its
inner wall. A linear regime of Faraday rotation of about 25 microT has been
observed with atomic number density within the vapor cell of about 10^9 cm-3.


title:
Response to D.T. Son's comment on ``Is there a `most perfect fluid'
  consistent with quantum field theory?''

abstract:
  This is a response to the comment, arXiv:0709.4651. It is noted that while
the comment raises an extremely interesting and subtle point, the original
conclusion that theoretically consistent exceptions exist for the proposed
general bound for the ratio of shear viscosity to entropy density, appears to
remain unaffected by the issue raised.


title:
Parallel multiscale modeling of biopolymer dynamics with hydrodynamic
  correlations

abstract:
  We employ a multiscale approach to model the translocation of biopolymers
through nanometer size pores. Our computational scheme combines microscopic
Molecular Dynamics (MD) with a mesoscopic Lattice Boltzmann (LB) method for the
solvent dynamics, explicitly taking into account the interactions of the
molecule with the surrounding fluid. We describe an efficient parallel
implementation of the method which exhibits excellent scalability on the Blue
Gene platform. We investigate both dynamical and statistical aspects of the
translocation process by simulating polymers of various initial configurations
and lengths. For a representative molecule size, we explore the effects of
important parameters that enter in the simulation, paying particular attention
to the strength of the molecule-solvent coupling and of the external electric
field which drives the translocation process. Finally, we explore the
connection between the generic polymers modeled in the simulation and DNA, for
which interesting recent experimental results are available.


title:
The Generalized Asymptotic Equipartition Property: Necessary and
  Sufficient Conditions

abstract:
  Suppose a string $X_1^n=(X_1,X_2,...,X_n)$ generated by a memoryless source
$(X_n)_{n\geq 1}$ with distribution $P$ is to be compressed with distortion no
greater than $D\geq 0$, using a memoryless random codebook with distribution
$Q$. The compression performance is determined by the ``generalized asymptotic
equipartition property'' (AEP), which states that the probability of finding a
$D$-close match between $X_1^n$ and any given codeword $Y_1^n$, is
approximately $2^{-n R(P,Q,D)}$, where the rate function $R(P,Q,D)$ can be
expressed as an infimum of relative entropies. The main purpose here is to
remove various restrictive assumptions on the validity of this result that have
appeared in the recent literature. Necessary and sufficient conditions for the
generalized AEP are provided in the general setting of abstract alphabets and
unbounded distortion measures. All possible distortion levels $D\geq 0$ are
considered; the source $(X_n)_{n\geq 1}$ can be stationary and ergodic; and the
codebook distribution can have memory. Moreover, the behavior of the matching
probability is precisely characterized, even when the generalized AEP is not
valid. Natural characterizations of the rate function $R(P,Q,D)$ are
established under equally general conditions.


title: Report on the second Mock LISA Data Challenge

abstract:
  The Mock LISA Data Challenges are a program to demonstrate LISA data-analysis
capabilities and to encourage their development. Each round of challenges
consists of several data sets containing simulated instrument noise and
gravitational-wave sources of undisclosed parameters. Participants are asked to
analyze the data sets and report the maximum information about source
parameters. The challenges are being released in rounds of increasing
complexity and realism: in this proceeding we present the results of Challenge
2, issued in January 2007, which successfully demonstrated the recovery of
signals from supermassive black-hole binaries, from ~20,000 overlapping
Galactic white-dwarf binaries, and from the extreme-mass-ratio inspirals of
compact objects into central galactic black holes.


title:
Collective modes in quantum electron glasses and electron-assisted
  hopping

abstract:
  We study electronic transport in Anderson insulators with strong Coulomb
interactions in dimensions d>=2. Close to the metal insulator transition where
the single particle localization length is much larger than
interparticle-distance, the interactions lead to a strongly correlated quantum
glass phase. Even though single particle excitations are localized and the
system is insulating, there are collective electronic modes which remain
delocalized down to parametrically small energies. These collective excitations
serve as a continuous bath which can provide the activation energy for variable
range hopping transport. This circumvents the energy conservation problem
arising when only discrete particle-hole excitations are present. In contrast
to the weak and material-dependent phonon-assisted hopping mechanism, the
activation by an electronic bath leads to a nearly universal prefactor e^2/h of
the Efros-Shklovskii conductance, as is observed in many recent experiments.


title: Localisations and Completions of Skew Power Series Rings

abstract:
  This paper is a natural continuation of the study of skew power series rings
A initiated in [P. Schneider and O. Venjakob, On the codimension of modules
over skew power series rings with applications to Iwasawa algebras, J. Pure
Appl. Algebra 204 (2005), 349 - 367.]. We construct skew Laurent series rings B
and show the existence of some canonical Ore sets S for the skew power series
rings A such that a certain completion of the localisation A_S is isomorphic to
B. This is applied to certain Iwasawa algebras. Finally we introduce subrings
of overconvergent skew Laurent series rings.


title: Spin waves and local magnetizations on the Penrose tiling

abstract:
  We consider a Heisenberg antiferromagnet on the Penrose tiling, a
quasiperiodic system having an inhomogeneous Neel-ordered ground state. Spin
wave energies and wavefunctions are studied in the linear spin wave
approximation. A linear dispersion law is found at low energies, as in other
bipartite antiferromagnets, with an effective spin wave velocity lower than in
the square lattice. Spatial properties of eigenmodes are characterized in
several different ways. At low energies, eigenstates are relatively extended,
and show multifractal scaling. At higher energies, states are more localized,
and, depending on the energy, confined to sites of a specified coordination
number. The ground state energy of this antiferromagnet, and local staggered
magnetizations are calculated. Perpendicular space projections are presented in
order to show the underlying simplicity of this "complex" ground state. A
simple analytical model, the two-tier Heisenberg star, is presented to explain
the staggered magnetization distribution in this antiferromagnetic system.


title:
Combined Integer and Variable Precision (CIVP) Floating Point
  Multiplication Architecture for FPGAs

abstract:
  In this paper, we propose an architecture/methodology for making FPGAs
suitable for integer as well as variable precision floating point
multiplication. The proposed work will of great importance in applications
which requires variable precision floating point multiplication such as
multi-media processing applications. In the proposed architecture/methodology,
we propose the replacement of existing 18x18 bit and 25x18 bit dedicated
multipliers in FPGAs with dedicated 24x24 bit and 24x9 bit multipliers,
respectively. We have proved that our approach of providing the dedicated 24x24
bit and 24x9 bit multipliers in FPGAs will make them efficient for performing
integer as well as single precision, double precision, and Quadruple precision
floating point multiplications.


title:
Hyperbolic dimension of Julia sets of meromorphic maps with logarithmic
  tracts

abstract:
  We prove that for meromorphic maps with logarithmic tracts (e.g. entire or
meromorphic maps with a finite number of poles from class $\mathcal B$), the
Julia set contains a compact invariant hyperbolic Cantor set of Hausdorff
dimension greater than 1. Hence, the hyperbolic dimension of the Julia set is
greater than 1.


title: Remarks on Congruence of 3-manifolds

abstract:
  We give two proofs that the 3-torus is not weakly d-congruent to the
connected sum of three S^1xS^2's, if d>2. We study how cohomology ring
structure relates to weak congruence. We give an example of three 3--manifolds
which are weakly 5-congruent but are not 5-congruent.


title: Partial Reversible Gates(PRG) for Reversible BCD Arithmetic

abstract:
  IEEE 754r is the ongoing revision to the IEEE 754 floating point standard and
a major enhancement to the standard is the addition of decimal format.
Furthermore, in the recent years reversible logic has emerged as a promising
computing paradigm having its applications in low power CMOS, quantum
computing, nanotechnology, and optical computing. The major goal in reversible
logic is to minimize the number of reversible gates and garbage outputs. Thus,
this paper proposes the novel concept of partial reversible gates that will
satisfy the reversibility criteria for specific cases in BCD arithmetic. The
partial reversible gate is proposed to minimize the number of reversible gates
and garbage outputs, while designing the reversible BCD arithmetic circuits.


title: A note on random walks in a hypercube

abstract:
  We study a simple random walk on an n-dimensional hypercube. For any starting
position we find the probability of hitting vertex a before hitting vertex b,
whenever a and b share the same edge. This generalizes the model in Doyle, P.,
and Snell, J., "Random Walks and Electric Networks", Mathematical Association
of America, 1984 (see Exercise 1.3.7 there).


title: New Systems Showing the Light-Time Effect

abstract:
  Two Algol-type eclipsing binary systems (EW Lyr and IV Cas) have been
investigated for period changes. Our study was primarily focused on the
light-time effect with an alternative explanation by magnetic activity cycles.
In the case of EW Lyr we have found a third body in the orbit with a period of
about 78 years, an amplitude A=0.052 days and orbital eccentricity e=0.57. For
IV Cas the long period is 58 years, amplitude A=0.034 days and zero
eccentricity. With these results we are also able to calculate mass functions
and minimal masses of these components.


title: Uniformizing Tropical Curves I: Genus Zero and One

abstract:
  In tropical geometry, given a curve in a toric variety, one defines a
corresponding graph embedded in Euclidean space. We study the problem of
reversing this process for curves of genus zero and one. Our methods focus on
describing curves by parameterizations, not by their defining equations; we
give parameterizations by rational functions in the genus zero case and by
non-archimedean elliptic functions in the genus one case. For genus zero
curves, those graphs which can be lifted can be characterized in a completely
combinatorial manner. For genus one curves, show that certain conditions
identified by Mikhalkin are sufficient and we also identify a new necessary
condition.


title: Finite density simulations using a determinant estimator

abstract:
  Previous investigations have shown that the canonical approach to simulating
QCD at finite density is promising. The algorithm we used in our earlier work
employs an exact calculation of the fermionic determinant which limits the size
of the lattices we can simulate. Interesting questions can only be answered if
we simulate at larger volume. In this paper we explore an algorithm, Hybrid
Noisy Monte Carlo, that employs a determinant estimator rather than an exact
calculation. We first present the technical aspects of the estimator, check
that the algorithm is correct by comparing it with our previous study, and then
discuss its merits. We will also discuss the challenges faced when simulating
larger lattice volumes.


title: Realistic Type IIB Supersymmetric Minkowski Flux Vacua

abstract:
  We show that there exist supersymmetric Minkowski vacua on Type IIB toroidal
orientifold with general flux compactifications where the RR tadpole
cancellation conditions can be relaxed elegantly. Then we present a realistic
Pati-Salam like model. At the string scale, the gauge symmetry can be broken
down to the Standard Model (SM) gauge symmetry, the gauge coupling unification
can be achieved naturally, and all the extra chiral exotic particles can be
decoupled so that we have the supersymmetric SMs with/without SM singlet(s)
below the string scale. The observed SM fermion masses and mixings can also be
obtained. In addition, the unified gauge coupling, the dilaton, the complex
structure moduli, the real parts of the K\"ahler moduli and the sum of the
imaginary parts of the K\"ahler moduli can be determined as functions of the
four-dimensional dilaton and fluxes, and can be estimated as well.


title: Quantum behaviour near a spacelike boundary in the c=1 matrix model

abstract:
  Certain time dependent configurations in the c=1 matrix model correspond to
string theory backgrounds which have spacelike boundaries and appear
geodesically incomplete. We investigate quantum mechanical properties of a
class of such configurations in the matrix model, in terms of fermionic
eigenvalues. We describe Hamiltonian evolution of the eigenvalue density using
several different time variables, some of which are infinite and some of which
are finite in extent. We derive unitary transformations relating these
different descriptions, and use those to calculate fermion correlators in the
time dependent background. Using the chiral formalism, we write the time
dependent configurations as a state in the original matrix model Hilbert space.


title: Terahertz detection in single wall carbon nanotubes

abstract:
  It is reported that terahertz radiation from 0.69 THz to 2.54 THz has been
sensitively detected in a device consisting of bundles of metallic carbon
nanotubes, quasi-optically coupled through a lithographically fabricated
antenna, and a silicon lens. The measured data are consistent with a bolometric
process and show promise for operation above 4.2 K.


title:
Beat Cepheids as Probes of Stellar and Galactic Metallicity: The New AGS
  Abundances

abstract:
  It is well known that the mere location of a Beat Cepheid model in a Period
Ratio \vs Period diagram (Petersen diagram) puts constraints on its metallicity
Z. But these bounds are sensitive to the mixture of elements that are lumped
into the parameter $Z$. In this short paper we update the previous results that
were based on the Grevesse-Noels solar mixture to the recent, revised Asplund,
Grevesse & Sauval (2005) (AGS) solar mixture.
  We also examine the effect of the envelope depth on the accuracy of the
computed pulsation periods. We find that for low period Cepheids with high Z
the customary approximation of envelope pulsation breaks down. It is necessary
to compute stellar models that extend to the center and to include burning and
composition inhomogeneities in the modeling. Fortunately, however, most Beat
Cepheids that have been observed so far seem to avoid that regime.


title: ANTARES Collaboration Proceedings of ICRC 2007

abstract:
  Contributions to ICRC 2007, Merida, Mexico. Contents pages for the
Contribution on behalf of the ANTARES Collaboration to the 30th ICRC that took
place in July 2007 in Merida, Mexico. The contents are in html form with
clickable links to the papers that exist on the Astrophysics archive.


title: Bijections from Dyck paths to 321-avoiding permutations revisited

abstract:
  There are (at least) three bijections from Dyck paths to 321-avoiding
permutations in the literature, due to Billey-Jockusch-Stanley, Krattenthaler,
and Mansour-Deng-Du. How different are they? Denoting them B,K,M respectively,
we show that M = B \circ L = K \circ L' where L is the classical
Kreweras-Lalanne involution on Dyck paths and L', also an involution, is a sort
of derivative of L. Thus K^{-1} \circ B, a measure of the difference between B
and K, is the product of involutions L' \circ L and turns out to be a very
curious bijection: as a permutation on Dyck n-paths it is an nth root of the
"reverse path" involution. The proof of this fact boils down to a geometric
argument involving pairs of nonintersecting lattice paths.


title: Star-formation in the HI bridge between M81 and M82

abstract:
  We present multi-wavelength observations of stellar features in the HI tidal
bridge connecting M81 and M82 in the region called Arp's Loop. We identify
eight young star-forming regions from Galaxy Evolution Explorer ultraviolet
observations. Four of these objects are also detected at H\alpha. We determine
the basic star formation history of Arp's Loop using F475W and F814W images
obtained with the Advanced Camera for Surveys on board the Hubble Space
Telescope. We find both a young (< 10 Myr) and an old (>1 Gyr) stellar
population with a similar spatial distribution and a metallicity Z~0.004. We
suggest that the old stellar population was formed in the stellar disk of M82
and/or M81 and ejected into the intergalactic medium during a tidal passage (~
200-300 Myr ago), whereas the young UV-bright stars have formed in the tidal
debris. The UV luminosities of the eight objects are modest and typical of
small clusters or OB associations. The tidal bridge between M81-M82 therefore
appears to be intermediate between the very low levels of star formation seen
in the Magellanic bridge and actively star-forming tidal tails associated with
major galaxy mergers.


title: Observational constraints on late-time Lambda(t) cosmology

abstract:
  The cosmological constant, i.e., the energy density stored in the true vacuum
state of all existing fields in the Universe, is the simplest and the most
natural possibility to describe the current cosmic acceleration. However,
despite its observational successes, such a possibility exacerbates the well
known cosmological constant problem, requiring a natural explanation for its
small, but nonzero, value. In this paper we study cosmological consequences of
a scenario driven by a varying cosmological term, in which the vacuum energy
density decays linearly with the Hubble parameter. We test the viability of
this scenario and study a possible way to distinguish it from the current
standard cosmological model by using recent observations of type Ia supernova
(Supernova Legacy Survey Collaboration), measurements of the baryonic acoustic
oscillation from the Sloan Digital Sky Survey and the position of the first
peak of the cosmic microwave background angular spectrum from the three-year
Wilkinson Microwave Anisotropy Probe.


title:
A feedback approach to bifurcation analysis in biochemical networks with
  many parameters

abstract:
  Feedback circuits in biochemical networks which underly cellular signaling
pathways are important elements in creating complex behavior. A specific aspect
thereof is how stability of equilibrium points depends on model parameters. For
biochemical networks, which are modelled using many parameters, it is typically
very difficult to estimate the influence of parameters on stability. Finding
parameters which result in a change in stability is a key step for a meaningful
bifurcation analysis. We describe a method based on well known approaches from
control theory, which can locate parameters leading to a change in stability.
The method considers a feedback circuit in the biochemical network and relates
stability properties to the control system obtained by loop--breaking. The
method is applied to a model of a MAPK cascade as an illustrative example.


title:
Inflows and Outflows in the Dwarf Starburst Galaxy NGC 5253:
  High-Resolution HI Observations

abstract:
  VLA and Parkes 64 m radiotelescope 21-cm observations of the starburst dwarf
galaxy NGC 5253 reveal a multi-component non-axisymmetric HI distribution. The
component associated with the stellar body shows evidence for a small amount of
rotational support aligned with the major axis, in agreement with optically
measured kinematics and consistent with the small galaxian mass. Approximately
20-30% of the HI emission is associated with a second component, an HI "plume"
extending along the optical minor axis to the southeast. We consider outflow,
inflow, and tidal origins for this feature. Outflow appears improbable, inflow
is a possibility, and tidal debris is most consistent with the observations.
These observations also reveal a filamentary third component that includes an
800 pc diameter HI shell or bubble to the west of the nucleus, coinciding with
an Halpha shell. The mass of HI in the shell may be as large as ~4x10^6 Msun.
This large mass, coupled with the lack of expansion signatures in the neutral
and ionized gas (v<30 km/s), suggests that this feature may be an example of a
starburst-blown bubble stalled by interaction with a massive neutral envelope.
Many other HI kinematic features closely resemble those seen in Halpha emission
from the ionized gas, supporting the interpretation of neutral and ionized gas
outflow at velocities of ~30 km/s. Comparison between extinction estimates from
the Balmer emission-line decrement and the HI column densities suggest a
gas-to-dust ratio 2-3 times the Galactic value in this low-metallicity (Z=1/4
Zsun) galaxy.


title: Evolution of density perturbations in decaying vacuum cosmology

abstract:
  We study cosmological perturbations in the context of an interacting dark
energy model, in which the cosmological term decays linearly with the Hubble
parameter, with concomitant matter production. A previous joint analysis of the
redshift-distance relation for type Ia supernovas, baryonic acoustic
oscillations, and the position of the first peak in the anisotropy spectrum of
the cosmic microwave background has led to acceptable values for the
cosmological parameters. Here we present our analysis of small perturbations,
under the assumption that the cosmological term, and therefore the matter
production, are strictly homogeneous. Such a homogeneous production tends to
dilute the matter contrast, leading to a late-time suppression in the power
spectrum. Nevertheless, an excellent agreement with the observational data can
be achieved by using a higher matter density as compared to the concordance
value previously obtained. This may indicate that our hypothesis of homogeneous
matter production must be relaxed by allowing perturbations in the interacting
cosmological term.


title:
Timing and Precession of the Young, Relativistic Binary Pulsar PSR
  J1906+0746

abstract:
  We present an updated timing solution and an analysis of the profile
evolution - including precession and beam shape - of the young, relativistic
binary pulsar J1906+0746. The 144-ms pulsar, in a 3.98-hour orbit with
eccentricity 0.085 (Lorimer et al. 2006), was initially discovered during the
early stages of the ALFA (Arecibo L-band Feed Array) pulsar survey (Cordes et
al. 2006) using the 305-metre Arecibo telescope and was subsequently found in
archival Parkes Multibeam Survey data. We have since been regularly monitoring
the system using the Arecibo and Green Bank telescopes, and include data from
the Jodrell Bank, Parkes, Nancay and Westerbork telescopes. The nature of the
binary companion will also be discussed based on improved estimates of the
total and companion masses obtained from the updated timing solution.


title: Tunable Plasmon Molecules in Overlapping Nanovoids

abstract:
  Coupled and shape-tailored metallic nanoparticles are known to exhibit
hybridized plasmon resonances. This Letter discuss the optical properties of a
complementary system formed by overlapped nanovoid dimers buried in gold and
filled with silica. This is an alternative route for plasmon engineering that
benefits from vanishing radiation losses. Our analysis demonstrates the
possibility of designing artificial plasmon molecules on the basis of void
plasmon hybridization, which allows fine mode tuning by varying the overlap
between voids. The proposed structures could find application to both signal
processing through buried optical elements and tunable-plasmon biosensing.


title: New results using the canonical approach to finite density QCD

abstract:
  We present some new results regarding simulations of finite density QCD based
on a canonical approach. A previous study has shown that such simulations are
feasible, at least on small lattices. In the current study, we investigate some
of the issues left open: we study the errors introduced by our approximation of
the action and we show how to tune it to reduce the cost of the simulations
while keeping the errors under control. To further reduce the cost of the
simulations, we check the reliability of reweighting method with respect to the
baryon number. Finally, using these optimizations, we carry out the simulations
at larger densities than in our previous study to look for signals of a phase
transition.


title:
Transformation equations for the kinetic energy of the same particle:
  Filling the gap in special relativity literature

abstract:
  Transformation equations for the kinetic energy of a tardyon are derived in
the limits of classical and of special relativity theory. Two formulas are
presented. In the first one the energy of the particle in one of the involved
reference frames is presented as a function of its proper energy, of the
relative velocity of the two frames and of its speed in the second one. In the
second one the kinetic energy in one of the involved reference frames is
expressed as a function of its kinetic energy in the second one of its proper
energy, of the relative velocity of the involved inertial reference frames and
of its velocity relative to that frame. The obtained results are extended to
the case of a photon that moves under the same geometrical conditions,
recovering the formulas that account for the relativistic Doppler Effect,
illustrating the behavior of a transformation equation when it should account
for the properties of an electron and for those of a photon as well.


title:
Bounds on the tight-binding approximation for the Gross-Pitaevskii
  equation with a periodic potential

abstract:
  We justify the validity of the discrete nonlinear Schrodinger equation for
the tight-binding approximation in the context of the Gross-Pitaevskii equation
with a periodic potential. Our construction of the periodic potential and the
associated Wannier functions is based on the previous work, while our analysis
involving energy estimates and Gronwall's inequality addresses time-dependent
localized solutions on large but finite time intervals.


title: Regularity and the Cesaro-Nevai class

abstract:
  We consider OPRL and OPUC with measures regular in the sense of
Ullman-Stahl-Totik and prove consequences on the Jacobi parameters or
Verblunsky coefficients. For example, regularity on $[-2,2]$ implies
$\lim_{N\to\infty} N^{-1} [\sum_{n=1}^N (a_n-1)^2 + b_n^2] =0$.


title: On the Rank of Random Sparse Matrices

abstract:
  We investigate the rank of random (symmetric) sparse matrices. Our main
finding is that with high probability, any dependency that occurs in such a
matrix is formed by a set of few rows that contains an overwhelming number of
zeros. This allows us to obtain an exact estimate for the co-rank.


title:
Exact exponents of edge singularities in dynamic correlation functions
  of 1D Bose gas

abstract:
  The spectral function and dynamic structure factor of bosons interacting by
contact repulsion and confined to one dimension exhibit power-law singularities
along the dispersion curves of the collective modes. We find the corresponding
exponents exactly, by relating them to the known Bethe ansatz solution of the
Lieb-Liniger model. The found exponents vary considerably with the interaction
strength and momentum. Remarkably, the Luttinger liquid theory predictions for
the exponents fail even at low energies, once the immediate vicinities of the
edges are considered.


title: Continuum Emission by Cooling Clouds

abstract:
  The collapse of baryons into the center of a host dark matter halo is
accompanied by radiation that may be detectable as compact (< 10 kpc)
UV-continuum and Lyman Alpha (hereafter Lya) emission with Lya luminosities as
high as ~1e42-1e43 erg/s in halos of mass M=1e11-10e12 solar masses. We show
that the observed equivalent width (EW) of the Lya line emitted by these
cooling clouds is EW 400 Angstrom (restframe). These luminosities and EWs are
comparable to those detected in narrowband surveys for redshifted Lya emission.
The rest-frame ultraviolet of Lya emitting cooling clouds radiation may be
dominated by two-photon transitions from 2s->1s. The resulting spectrum can
distinguish cooling clouds from a broad class of young star forming galaxies.


title: Quaternionic Analysis, Representation Theory and Physics

abstract:
  We develop quaternionic analysis using as a guiding principle representation
theory of various real forms of the conformal group. We first review the
Cauchy-Fueter and Poisson formulas and explain their representation theoretic
meaning. The requirement of unitarity of representations leads us to the
extensions of these formulas in the Minkowski space, which can be viewed as
another real form of quaternions. Representation theory also suggests a
quaternionic version of the Cauchy formula for the second order pole.
Remarkably, the derivative appearing in the complex case is replaced by the
Maxwell equations in the quaternionic counterpart. We also uncover the
connection between quaternionic analysis and various structures in quantum
mechanics and quantum field theory, such as the spectrum of the hydrogen atom,
polarization of vacuum, one-loop Feynman integrals. We also make some further
conjectures. The main goal of this and our subsequent paper is to revive
quaternionic analysis and to show profound relations between quaternionic
analysis, representation theory and four-dimensional physics.


title: Equilibrium measures and capacities in spectral theory

abstract:
  This is a comprehensive review of the uses of potential theory in studying
the spectral theory of orthogonal polynomials. Much of the article focuses on
the Stahl-Totik theory of regular measures, especially the case of OPRL and
OPUC. Links are made to the study of ergodic Schrodinger operators where one of
our new results implies that, in complete generality, the spectral measure is
supported on a set of zero Hausdorff dimension (indeed, of capacity zero) in
the region of strictly positive Lyapunov exponent. There are many examples and
some new conjectures and indications of new research directions. Included are
appendices on potential theory and on Fekete-Szego theory.


title: Monotone Jacobi parameters and non-Szego weights

abstract:
  We relate asymptotics of Jacobi parameters to asymptotics of the spectral
weights near the edges. Typical of our results is that for $a_n\equiv 1$, $b_n
=-C n^{-\beta}$ ($0<\beta< \frac23)$, one has $d\mu(x)= w(x) dx$ on $(-2,2)$,
and near $x=2$, $w(x)=e^{-2Q(x)}$ where \[ Q(x)=\beta^{-1} C^{\frac{1}{\beta}}
\frac{\Gamma(\frac32)\Gamma(\frac{1}\beta}-\frac12)(2-x)^{\frac12
-\frac{1}{\beta}}}{\Gamma(\frac{1}{\beta}+1)}(1+O((2-x))) \]


title: Ab initio no-core shell model calculations for light nuclei

abstract:
  An overview of the ab initio no-core shell model is presented. Recent results
for light nuclei obtained with the chiral two-nucleon and three-nucleon
interactions are highlighted. Cross section calculations of capture reactions
important for astrophysics are discussed. The extension of the ab initio
no-core shell model to the description of nuclear reactions by the resonating
group method technique is outlined.


title: The Analytic Theory of Matrix Orthogonal Polynomials

abstract: We give a survey of the analytic theory of matrix orthogonal polynomials.


title: The fundamental group of random 2-complexes

abstract:
  We study Linial-Meshulam random 2-complexes, which are two-dimensional
analogues of Erd\H{o}s-R\'enyi random graphs. We find the threshold for simple
connectivity to be p = n^{-1/2}. This is in contrast to the threshold for
vanishing of the first homology group, which was shown earlier by Linial and
Meshulam to be p = 2 log(n)/n. We use a variant of Gromov's local-to-global
theorem for linear isoperimetric inequalities to show that when p = O(n^{-1/2
-\epsilon}) the fundamental group is word hyperbolic. Along the way we classify
the homotopy types of sparse 2-dimensional simplicial complexes and establish
isoperimetric inequalities for such complexes. These intermediate results do
not involve randomness and may be of independent interest.


title:
A Study of e+e- -> H0A0 Production at 1 TeV and the Constrain on Dark
  Matter Density

abstract:
  This paper reports preliminary results of a study of the HA production
process in e+e- collisions at a 1 TeV linear collider and their implication in
the study of dark matter at particle colliders. The analysis is carried out
using full Geant-4 simulation and reconstruction for the LDC detector model.


title:
A formula for the fractal dimension d approx. 0.87 of the Cantorian set
  underlying the Devil's staircase associated with the Circle Map

abstract:
  The Cantor set complementary to the Devil's Staircase associated with the
Circle Map has a fractal dimension d approximately equal to 0.87, a value that
is universal for a wide range of maps, such results being of a numerical
character. In this paper we deduce a formula for such dimensional value. The
Devil's Staircase associated with the Circle Map is a function that transforms
horizontal unit interval I onto vertical I, and is endowed with the
Farey-Brocot (F-B) structure in the vertical axis via the rational heights of
stability intervals. The underlying Cantor-dust fractal set Omega in the
horizontal axis --Omega contained in I, with fractal dimension d(Omega) approx.
0.87-- has a natural covering with segments that also follow the F-B hierarchy:
therefore, the staircase associates vertical I (of unit dimension) with
horizontal Omega in I (of dimension approx. 0.87), i.e. it selects a certain
subset Omega of I, both sets F- B structured, the selected Omega with smaller
dimension than that of I. Hence, the structure of the staircase mirrors the F-
B hierarchy. In this paper we consider the subset Omega-F-B of I that
concentrates the measure induced by the F-B partition and calculate its
Hausdorff dimension, i.e. the entropic or information dimension of the F-B
measure, and show that it coincides with d(Omega) approx. 0.87. Hence, this
dimensional value stems from the F-B structure, and we draw conclusions and
conjectures from this fact. Finally, we calculate the statistical "Euclidean"
dimension (based on the ordinary Lebesgue measure) of the F-B partition, and we
show that it is the same as d(Omega-F-B), which permits conjecturing on the
universality of the dimensional value d approximately equal to 0.87.


title: Mathematical Aspects of Vacuum Energy on Quantum Graphs

abstract:
  We use quantum graphs as a model to study various mathematical aspects of the
vacuum energy, such as convergence of periodic path expansions, consistency
among different methods (trace formulae versus method of images) and the
possible connection with the underlying classical dynamics.
  We derive an expansion for the vacuum energy in terms of periodic paths on
the graph and prove its convergence and smooth dependence on the bond lengths
of the graph. For an important special case of graphs with equal bond lengths,
we derive a simpler explicit formula.
  The main results are derived using the trace formula. We also discuss an
alternative approach using the method of images and prove that the results are
consistent. This may have important consequences for other systems, since the
method of images, unlike the trace formula, includes a sum over special
``bounce paths''. We succeed in showing that in our model bounce paths do not
contribute to the vacuum energy. Finally, we discuss the proposed possible link
between the magnitude of the vacuum energy and the type (chaotic vs.
integrable) of the underlying classical dynamics. Within a random matrix model
we calculate the variance of the vacuum energy over several ensembles and find
evidence that the level repulsion leads to suppression of the vacuum energy.


title:
Global exploration of the energy landscape of solids on the ab initio
  level

abstract:
  Predicting which crystalline modifications can be present in a chemical
system requires the global exploration of its energy landscape. Due to the
large computational effort involved, in the past this search for sufficiently
stable minima has been performed employing a variety of empirical potentials
and cost functions followed by a local optimization on the ab initio level.
However, this entails the risk of overlooking important modifications that are
not modeled accurately using empirical potentials. In order to overcome this
critical limitation, we develop an approach to employ ab initio energy
functions during the global optimization phase of the structure prediction. As
an example, we perform a global exploration of the landscape of LiF on the ab
initio level and show that the relevant crystalline modifications are found
during the search.


title:
Testing Quantum Devices: Practical Entanglement Verification in
  Bipartite Optical Systems

abstract:
  We present a method to test quantum behavior of quantum information
processing devices, such as quantum memories, teleportation devices, channels
and quantum key distribution protocols. The test of quantum behavior can be
phrased as the verification of effective entanglement. Necessary separability
criteria are formulated in terms of a matrix of expectation values in
conjunction with the partial transposition map. Our method is designed to
reduce the resources for entanglement verification. A particular protocol based
on coherent states and homodyne detection is used to illustrate the method. A
possible test for the quantum nature of memories using two non-orthogonal
signal states arises naturally. Furthermore, closer inspection of the
measurement process in terms of the Stokes operators reveals a security threat
for quantum key distribution involving phase reference beams.


title: Finding a Feasible Flow in a Strongly Connected Network

abstract:
  We consider the problem of finding a feasible single-commodity flow in a
strongly connected network with fixed supplies and demands, provided that the
sum of supplies equals the sum of demands and the minimum arc capacity is at
least this sum. A fast algorithm for this problem improves the worst-case time
bound of the Goldberg-Rao maximum flow method by a constant factor. Erlebach
and Hagerup gave an linear-time feasible flow algorithm. We give an arguably
simpler one.


title:
Universal computation with limited resources: Belousov-Zhabotinsky and
  Physarum computers

abstract:
  Using the examples of an excitable chemical system (Belousov-Zhabotinsky
medium) and plasmodium of Physarum polycephalum we show that universal
computation in a geometrically unconstrained medium is only possible when
resources (excitability or concentration of nutrients) are limited. In
situations of limited resources the systems studied develop travelling
localizations. The localizations are elementary units of dynamical logical
circuits in collision-based computing architectures.


title: Parity Forwarding for Multiple-Relay Networks

abstract:
  This paper proposes a relaying strategy for the multiple-relay network in
which each relay decodes a selection of transmitted messages by other
transmitting terminals, and forwards parities of the decoded codewords. This
protocol improves the previously known achievable rate of the
decode-and-forward (DF) strategy for multirelay networks by allowing relays to
decode only a selection of messages from relays with strong links to it. Hence,
each relay may have several choices as to which messages to decode, and for a
given network many different parity forwarding protocols may exist. A tree
structure is devised to characterize a class of parity forwarding protocols for
an arbitrary multirelay network. Based on this tree structure, closed-form
expressions for the achievable rates of these DF schemes are derived. It is
shown that parity forwarding is capacity achieving for new forms of degraded
relay networks.


title:
Search for CPT and Lorentz Violation in B0-B0bar Oscillations with
  Dilepton Events

abstract:
  We report results of a search for CPT and Lorentz violation in B0-B0bar
oscillations using inclusive dilepton events from 232 million Y(4S) --> BBbar
decays recorded by the BABAR detector at the PEP-II B Factory at SLAC. We find
2.8sigma significance, compatible with no signal, for variations in the complex
CPT violation parameter z at the Earth's sidereal frequency and extract values
for the quantities \Delta(a_\mu) in the general Lorentz-violating
standard-model extension. The spectral powers for variations in z over the
frequency range 0.26/year to 2.1/day are also compatible with no signal.


title: On the universal Gr\"obner bases of varieties of minimal degree

abstract:
  A universal Gr\"obner basis of an ideal is the union of all its reduced
Gr\"obner bases. It is contained in the Graver basis, the set of all primitive
elements. Obtaining an explicit description of either of these sets, or even a
sharp degree bound for their elements, is a nontrivial task.
  In their '95 paper, Graham, Diaconis and Sturmfels give a nice combinatorial
description of the Graver basis for any rational normal curve in terms of
primitive partition identities. Their result is extended here to rational
normal scrolls. The description of the Graver bases is given in terms of
colored partition identities. This leads to a sharp bound on the degree of
Graver basis elements, which is always attained by a circuit.
  Finally, for any variety obtained from a scroll by a sequence of projections
to some of the coordinate hyperplanes, the degree of any element in any reduced
Gr\"obner basis is bounded by the degree of the variety.


title: In Orbit Timing Calibration of the Hard X-Ray Detector on Board Suzaku

abstract:
  The hard X-ray detector (HXD) on board the X-ray satellite Suzaku is designed
to have a good timing capability with a 61 $\mu$s time resolution. In addition
to detailed descriptions of the HXD timing system, results of in-orbit timing
calibration and performance of the HXD are summarized. The relative accuracy of
time measurements of the HXD event was confirmed to have an accuracy of
$1.9\times 10^{-9}$ s s$^{-1}$ per day, and the absolute timing was confirmed
to be accurate to 360 $\mu$s or better. The results were achieved mainly
through observations of the Crab pulsar, including simultaneous ones with RXTE,
INTEGRAL, and Swift.


title:
Suzaku Discovery of Hard X-ray Pulsations from the Rotating Magnetized
  White Dwarf, AE Aquarii

abstract:
  The fast rotating magnetized white dwarf, AE Aquarii, was observed with
Suzaku, in October 2005 and October 2006 with exposures of 53.1 and 42.4 ks,
respectively. In addition to clear spin modulation in the 0.5--10 keV band of
the XIS data at the barycentric period of 33.0769 \pm 0.0001 s, the 10--30 keV
HXD data in the second half of the 2005 observation also showed statistically
significant periodic signals at a consistent period. On that occasion, the
spin-folded HXD light curve exhibited two sharp spikes separated by about 0.2
cycles in phase, in contrast to approximately sinusoidal profiles observed in
energies below about 4 keV. The folded 4--10 keV XIS light curves are
understood as a superposition of those two types of pulse profiles. The phase
averaged 1.5--10 keV spectra can be reproduced by two thermal components with
temperatures of $2.90_{-0.16}^{+0.20}$ keV and $0.53_{-0.13}^{+0.14}$ keV, but
the 12-25 keV HXD data show a significant excess above the extrapolated model.
This excess can be explained by either a power-law model with photon index of
$1.12_{-0.62}^{+0.63}$ or a third thermal component with a temperature of
$54_{-47}^{+26}$ keV. At a distance of 102 pc, the 4--30 keV luminosities of
the thermal and the additional components become $1.7_{-0.6}^{+1.3}$ and
$5.3_{-0.3}^{+15.3} \times 10^{29}$ erg s$^{-1}$, respectively. The latter
corresponds to 0.09% of the spin down energy of the object. Possible emission
mechanisms of the hard pulsations are discussed, including in particular
non-thermal ones.


title:
Periodic energy switching of bright solitons in mixed coupled nonlinear
  Schr{\"o}dinger equations with linear self and cross coupling terms

abstract:
  The bright soliton solutions of the mixed 2-coupled nonlinear Schr{\"o}dinger
(CNLS) equations with linear self and cross coupling terms have been obtained
by identifying a transformation that transforms the corresponding equation to
the integrable mixed 2-CNLS equations. The study on the collision dynamics of
bright solitons shows that there exists periodic energy switching, due to the
coupling terms. This periodic energy switching can be controlled by the new
type of shape changing collisions of bright solitons arising in mixed 2-CNLS
system, characterized by intensity redistribution, amplitude dependent phase
shift and relative separation distance. We also point out that this system
exhibits large periodic intensity switching even with very small linear self
coupling strengths.


title:
A Risk-Sensitive Portfolio Optimization Problem with Fixed Incomes
  Securities

abstract:
  We discuss a class of risk-sensitive portfolio optimization problems. We
consider the portfolio optimization model investigated by Nagai in 2003. The
model by its nature can include fixed income securities as well in the
portfolio. Under fairly general conditions, we prove the existence of optimal
portfolio in both finite and infinite horizon problems.