title: Equivariant symmetric bilinear torsions

abstract:
  We extend the main result in the previous paper of Zhang and the author
relating the Milnor-Turaev torsion with the complex valued analytic torsion to
the equivariant case.


title: Two-pion-exchange contributions to the pp\to pp\pi^0 reaction

abstract:
  Our previous study of the near-threshold pp\to pp\pi^0 reaction based on a
hybrid nuclear effective field theory is further elaborated by examining the
momentum dependence of the relevant transition operators. We show that the
two-pion exchange diagrams give much larger contributions than the one-pion
exchange diagram, even though the former is of higher order in the Weinberg
counting scheme. The relation between our results and an alternative counting
scheme, the momentum counting scheme, is also discussed.


title:
Hardy and Rellich type inequalities with remainders for Baouendi-Grushin
  vector fields

abstract:
  In this paper we study Hardy and Rellich type inequalities for
Baouendi-Grushin vector fields : $\nabla_{\gamma}=(\nabla_x,
|x|^{2\gamma}\nabla_y)$ where $\gamma>0$, $\nabla_x$ and $\nabla_y$ are usual
gradient operators in the variables $x\in \mathbb{R}^m$ and $y\in\mathbb{R}^k$,
respectively. In the first part of the paper, we prove some weighted Hardy type
inequalities with remainder terms. In the second part, we prove two versions of
weighted Rellich type inequality on the whole space. We find sharp constants
for these inequalities. We also obtain their improved versions for bounded
domains.


title: Resummation Effects in the Search of SM Higgs Boson at Hadron Colliders

abstract:
  We examine the soft-gluon resummation effects, including the exact spin
correlations among the final state particles, in the search of the Standard
Model Higgs boson, via the process $gg\to H\to WW/ZZ \to 4 leptons, at the
Tevatron and the LHC. A comparison between the resummation and the
Next-to-Leading order (NLO) calculation is performed after imposing various
kinematics cuts suggested in the literature for the Higgs boson search. For the
$H\to ZZ$ mode, the resummation effects increase the acceptance of the signal
events by about 25%, as compared to the NLO prediction, and dramatically alter
various kinematics distributions of the final state leptons. For the $H\to WW$
mode, the acceptance rates of the signal events predicted by the resummation
and NLO calculations are almost the same, but some of the predicted kinematical
distributions are quite different. Thus, to precisely determine the properties
of the Higgs boson at hadron colliders, the soft-gluon resummation effects have
to be taken into account.


title: Triquark structure and isospin symmetry breaking in exotic Ds mesons

abstract:
  The color anti-triplet triquark $q\bar{q}\bar{q}$ is considered as a compact
component in the tetraquark structure $cq\bar{q}\bar{q}$ of exotic $D_{s}$
mesons. We discuss the mass spectrum and the flavor mixing of the triquarks by
using the instanton induced interaction and the one-gluon exchange potentials.
As a characteristic property of the triquark, we investigate the isospin
violation. It is shown that the flavor $\bar{\bf 3}$ (isosinglet) and $\bf 6$
(isotriplet) states may be strongly mixed and then are identified with
$D_{s}(2632)$.


title: Prediction of future fifteen solar cycles

abstract:
  In the previous study (Hiremath 2006a), the solar cycle is modeled as a
forced and damped harmonic oscillator and from all the 22 cycles (1755-1996),
long-term amplitudes, frequencies, phases and decay factor are obtained. Using
these physical parameters of the previous 22 solar cycles and by an {\em
autoregressive model}, we predict the amplitude and period of the future
fifteen solar cycles. Predicted amplitude of the present solar cycle (23)
matches very well with the observations. The period of the present cycle is
found to be 11.73 years. With these encouraging results, we also predict the
profiles of future 15 solar cycles. Important predictions are : (i) the period
and amplitude of the cycle 24 are 9.34 years and 110 ($\pm 11$), (ii) the
period and amplitude of the cycle 25 are 12.49 years and 110 ($\pm$ 11), (iii)
during the cycles 26 (2030-2042 AD), 27 (2042-2054 AD), 34 (2118-2127 AD), 37
(2152-2163 AD) and 38 (2163-2176 AD), the sun might experience a very high
sunspot activity, (iv) the sun might also experience a very low (around 60)
sunspot activity during cycle 31 (2089-2100 AD) and, (v) length of the solar
cycles vary from 8.65 yrs for the cycle 33 to maximum of 13.07 yrs for the
cycle 35.


title:
Comparaison entre cohomologie cristalline et cohomologie \'etale
  $p$-adique sur certaines vari\'et\'es de Shimura

abstract:
  Let $X$ be an integral model at a prime $p$ of a Shimura variety of PEL type
having good reduction, associated to a reductive group $G$. To $\mathbb{Z}_p$
reprsententations of the group $G$ can be associated two kinds of sheaves :
crystals on the special fiber of $X$, and locally constant \'etale sheaves on
the generic fiber. We establish a comparison between the cohomology of these
two kinds of sheaves.


title: Large portfolio losses: A dynamic contagion model

abstract:
  Using particle system methodologies we study the propagation of financial
distress in a network of firms facing credit risk. We investigate the
phenomenon of a credit crisis and quantify the losses that a bank may suffer in
a large credit portfolio. Applying a large deviation principle we compute the
limiting distributions of the system and determine the time evolution of the
credit quality indicators of the firms, deriving moreover the dynamics of a
global financial health indicator. We finally describe a suitable version of
the "Central Limit Theorem" useful to study large portfolio losses. Simulation
results are provided as well as applications to portfolio loss distribution
analysis.


title:
Carleman estimates and unique continuation for second order parabolic
  equations with nonsmooth coefficients

abstract:
  This work is devoted to the strong unique continuation problem for second
order parabolic equations with nonsmooth coefficients. Introduction and
bibliography have been revised.


title:
Specialized computer algebra system for application in general
  relativity

abstract:
  A brief characteristic of the specialized computer algebra system GRG_EC
intended for symbolic computations in the field of general relativity is given.


title: Rigidly rotating dust solutions depending upon harmonic functions

abstract:
  We write down the relevant field equations for a stationary axially symmetric
rigidly rotating dust source in such a way that the general solution depends
upon the solution of an elliptic equation and upon harmonic functions. Starting
with the dipole Bonnor solution, we built an asymptotically flat solution with
two curvature singularities on the rotational axis with diverging mass. Apart
from the two point singularities on the axis, the metric is regular everywhere.
Finally, we study a non-asymptotically flat solution with NUT charge and a
massless ring singularity, but with a well-defined mass-energy expression.


title:
The Green function estimates for strongly elliptic systems of second
  order

abstract:
  We establish existence and pointwise estimates of fundamental solutions and
Green's matrices for divergence form, second order strongly elliptic systems in
a domain $\Omega \subseteq \mathbb{R}^n$, $n \geq 3$, under the assumption that
solutions of the system satisfy De Giorgi-Nash type local H\"{o}lder continuity
estimates. In particular, our results apply to perturbations of diagonal
systems, and thus especially to complex perturbations of a single real
equation.


title:
Supporting Knowledge and Expertise Finding within Australia's Defence
  Science and Technology Organisation

abstract:
  This paper reports on work aimed at supporting knowledge and expertise
finding within a large Research and Development (R&D) organisation. The paper
first discusses the nature of knowledge important to R&D organisations and
presents a prototype information system developed to support knowledge and
expertise finding. The paper then discusses a trial of the system within an R&D
organisation, the implications and limitations of the trial, and discusses
future research questions.


title:
Reply to Comment on ``An Improved Experimental Limit on the Electric
  Dipole Moment of the Neutron''

abstract:
  The Authors reply to the Comment of Golub and Lamoreaux. The experimental
limit on the neutron electric dipole moment remains unchanged from that
previously announced.


title:
Lowest Landau Level of Relativistic Field Theories in a Strong
  Background Field

abstract:
  We consider gauge theories in a strong external magnetic like field. This
situation can appear either in conventional four-dimensional theories, but also
naturally in extra-dimensional theories and especially in brane world models.
We show that in the lowest Landau level approximation, some of the coordinates
become non-commutative. We find physical reasons to formal problems with
non-commutative gauge theories such as the issue with SU(N) gauge symmetries.
Our construction is applied to a minimal extension of the standard model. It is
shown that the Higgs sector might be non-commutative whereas the remaining
sectors of the standard model remain commutative. Signatures of this model at
the LHC are discussed. We then discuss an application to a dark matter sector
coupled to the Higgs sector of the standard model and show that here again,
dark matter could be non-commutative, the standard model fields remaining
commutative.


title:
Mechanical and dielectric relaxation spectra in seven highly viscous
  glass formers

abstract:
  Published dielectric and shear data of six molecular glass formers and one
polymer are evaluated in terms of a spectrum of thermally activated processes,
with the same barrier density for the retardation spectrum of shear and
dielectrics. The viscosity, an independent parameter of the fit, seems to be
related to the high-barrier cutoff time of the dielectric signal, in accordance
with the idea of a renewal of the relaxing entities after this critical time.
In the five cases where one can fit accurately, the temperature dependence of
the high-barrier cutoff follows the shoving model. The Johari-Goldstein peaks,
seen in four of our seven cases, are describable in terms of gaussians in the
barrier density, superimposed on the high-frequency tail of the
$\alpha$-process. Dielectric and shear measurements of the same substance find
the same peak positions and widths of these gaussians, but in general a
different weight.


title:
Computational and experimental imaging of Mn defects on GaAs (110)
  cross-sectional surface

abstract:
  We present a combined experimental and computational study of the (110)
cross-sectional surface of Mn $\delta$-doped GaAs samples. We focus our study
on three different selected Mn defect configurations not previously studied in
details, namely surface interstitial Mn, isolated and in pairs, and
substitutional Mn atoms on cationic sites (Mn$_{\rm Ga}$) in the first
subsurface layer. The sensitivity of the STM images to the specific local
environment allows to distinguish between Mn interstitials with nearest
neighbor As atoms (Int$_{\rm As}$) rather than Ga atoms (Int$_{\rm Ga}$), and
to identify the fingerprint of peculiar satellite features around subsurface
substitutional Mn. The simulated STM maps for Int$_{\rm As}$, both isolated and
in pairs, and Mn$_{\rm Ga}$ in the first subsurface layer are consistent with
some experimental images hitherto not fully characterized.


title: Distance preserving mappings from ternary vectors to permutations

abstract:
  Distance-preserving mappings (DPMs) are mappings from the set of all q-ary
vectors of a fixed length to the set of permutations of the same or longer
length such that every two distinct vectors are mapped to permutations with the
same or even larger Hamming distance than that of the vectors. In this paper,
we propose a construction of DPMs from ternary vectors. The constructed DPMs
improve the lower bounds on the maximal size of permutation arrays.


title: Hamiltonian Quantum Dynamics With Separability Constraints

abstract:
  Schroedinger equation on a Hilbert space ${\cal H}$, represents a linear
Hamiltonian dynamical system on the space of quantum pure states, the
projective Hilbert space $P {\cal H}$. Separable states of a bipartite quantum
system form a special submanifold of $P {\cal H}$.
  We analyze the Hamiltonian dynamics that corresponds to the quantum system
constrained on the manifold of separable states, using as an important example
the system of two interacting qubits. The constraints introduce nonlinearities
which render the dynamics nontrivial. We show that the qualitative properties
of the constrained dynamics clearly manifest the symmetry of the qubits system.
In particular, if the quantum Hamilton's operator has not enough symmetry, the
constrained dynamics is nonintegrable, and displays the typical features of a
Hamiltonian dynamical system with mixed phase space. Possible physical
realizations of the separability constraints are discussed.


title: Planck Length and Cosmology

abstract:
  We show that an unification of quantum mechanics and general relativity
implies that there is a fundamental length in Nature in the sense that no
operational procedure would be able to measure distances shorter than the
Planck length. Furthermore we give an explicit realization of an old proposal
by Anderson and Finkelstein who argued that a fundamental length in nature
implies unimodular gravity. Finally, using hand waving arguments we show that a
minimal length might be related to the cosmological constant which, if this
scenario is realized, is time dependent.


title: A Dynamic Algorithm for Blind Separation of Convolutive Sound Mixtures

abstract:
  We study an efficient dynamic blind source separation algorithm of
convolutive sound mixtures based on updating statistical information in the
frequency domain, andminimizing the support of time domain demixing filters by
a weighted least square method. The permutation and scaling indeterminacies of
separation, and concatenations of signals in adjacent time frames are resolved
with optimization of $l^1 \times l^\infty$ norm on cross-correlation
coefficients at multiple time lags. The algorithm is a direct method without
iterations, and is adaptive to the environment. Computations on recorded and
synthetic mixtures of speech and music signals show excellent performance.


title: Fast recursive filters for simulating nonlinear dynamic systems

abstract:
  A fast and accurate computational scheme for simulating nonlinear dynamic
systems is presented. The scheme assumes that the system can be represented by
a combination of components of only two different types: first-order low-pass
filters and static nonlinearities. The parameters of these filters and
nonlinearities may depend on system variables, and the topology of the system
may be complex, including feedback. Several examples taken from neuroscience
are given: phototransduction, photopigment bleaching, and spike generation
according to the Hodgkin-Huxley equations. The scheme uses two slightly
different forms of autoregressive filters, with an implicit delay of zero for
feedforward control and an implicit delay of half a sample distance for
feedback control. On a fairly complex model of the macaque retinal horizontal
cell it computes, for a given level of accuracy, 1-2 orders of magnitude faster
than 4th-order Runge-Kutta. The computational scheme has minimal memory
requirements, and is also suited for computation on a stream processor, such as
a GPU (Graphical Processing Unit).


title:
Spectra and symmetric eigentensors of the Lichnerowicz Laplacian on
  $S^n$

abstract:
  We compute the eigenvalues with multiplicities of the Lichnerowicz Laplacian
acting on the space of symmetric covariant tensor fields on the Euclidian
sphere $S^n$. The spaces of symmetric eigentensors are explicitly given.


title: CCD BV survey of 42 open clusters

abstract:
  We present results of a photometric survey whose aim was to derive structural
and astrophysical parameters for 42 open clusters. While our sample is
definitively not representative of the total open cluster sample in the Galaxy,
it does cover a wide range of cluster parameters and is uniform enough to allow
for simple statistical considerations. BV wide-field CCD photometry was
obtained for open clusters for which photometric, structural, and dynamical
evolution parameters were determined. The limiting and core radii were
determined by analyzing radial density profiles. The ages, reddenings, and
distances were obtained from the solar metallicity isochrone fitting. The mass
function was used to study the dynamical state of the systems, mass segregation
effect and to estimate the total mass and number of cluster members. This study
reports on the first determination of basic parameters for 11 out of 42
observed open clusters. The angular sizes for the majority of the observed
clusters appear to be several times larger than the catalogue data indicate.
The core and limiting cluster radii are correlated and the latter parameter is
3.2 times larger on average. The limiting radius increases with the cluster's
mass, and both the limiting and core radii decrease in the course of dynamical
evolution. For dynamically not advanced clusters, the mass function slope is
similar to the universal IMF slope. For more evolved systems, the effect of
evaporation of low-mass members is clearly visible. The initial mass
segregation is present in all the observed young clusters, whereas the
dynamical mass segregation appears in clusters older than about log(age)=8.
Low-mass stars are deficient in the cores of clusters older than log(age)=8.5
and not younger than one relaxation time.


title: Geometry and Dynamics of Quantum State Diffusion

abstract:
  Riemannian metric on real 2n-dimensional space associated with the equation
governing complex diffusion of pure states of an open quantum system is
introduced and studied. Examples of a qubit under the influence of dephasing
and thermal environments are used to show that the curvature of the diffusion
metric is a good indicator of the properties of the environment dominated
evolution and its stability.


title:
Investigation of transit-selected exoplanet candidates from the MACHO
  survey

abstract:
  Context: Planets outside our solar system transiting their host star, i. e.
those with an orbital inclination near 90 degree, are of special interest to
derive physical properties of extrasolar planets. With the knowledge of the
host star's physical parameters, the planetary radius can be determined.
Combined with spectroscopic observations the mass and therefore the density can
be derived from Doppler-measurements. Depending on the brightness of the host
star, additional information, e. g. about the spin-orbit alignment between the
host star and planetary orbit, can be obtained.
  Aims: The last few years have witnessed a growing success of transit surveys.
Among other surveys, the MACHO project provided nine potential transiting
planets, several of them with relatively bright parent stars. The photometric
signature of a transit event is, however, insufficient to confirm the planetary
nature of the faint companion. The aim of this paper therefore is a
determination of the spectroscopic parameters of the host stars as well as a
dynamical mass determination through Doppler-measurements.
  Methods: We have obtained follow-up high-resolution spectra for five stars
selected from the MACHO sample, which are consistent with transits of
low-luminosity objects. Radial velocities have been determined by means of
cross-correlation with model spectra. The MACHO light curves have been compared
to simulations based on the physical parameters of the system derived from the
radial velocities and spectral analyses.
  Aims: We show that all transit light curves of the exoplanet candidates
analysed in this work can be explained by eclipses of stellar objects, hence
none of the five transiting objects is a planet.


title:
On families of rational curves in the Hilbert square of a surface (with
  an Appendix by Edoardo Sernesi)

abstract:
  Under natural hypotheses we give an upper bound on the dimension of families
of singular curves with hyperelliptic normalizations on a surface S with p_g(S)
>0 via the study of the associated families of rational curves in Hilb^2(S).
  We use this result to prove the existence of nodal curves of geometric genus
3 with hyperelliptic normalizations, on a general K3 surface, thus obtaining
specific 2-dimensional families of rational curves in its Hilbert square. We
describe two infinite series of examples of general, primitively polarized K3's
such that their Hilbert squares contain a IP^2 or a threefold birational to a
IP^1-bundle over a K3.
  We discuss some consequences on the Mori cone of the Hilbert square of a
general K3.


title:
Anisotropy and Magnetic Field Effects on the Genuine Multipartite
  Entanglement of Multi-Qubit Heisenberg {\it XY} Chains

abstract:
  It has been shown that, for the two-qubit Heisenberg XY model, anisotropy and
magnetic field may together be used to produce entanglement for any finite
temperature by adjusting the external magnetic field beyond some finite
critical strength. This interesting result arises from an analysis employing
the Wootters concurrence, a computable measure of entanglement for two-qubit
states. Recently, Mintert {\em et al.} proposed generalizations of Wootters
concurrence for multipartite states. These MKB concurrences possess a
mathematical property that enables one to understand the origin of this
characteristic behavior. Here, we first study the effect of anisotropy and
magnetic field on the multipartite thermal entanglement of a four-qubit
Heisenberg XY chain using the MKB concurrences. We show that this model
exhibits characteristic behavior similar to that of the two-qubit model. In
addition, we show that this can again be understood using the same mathematical
property. Next, we show that the six-qubit Heisenberg XY chain possesses
properties necessary for it to have the characteristic behavior too. Most
importantly, it is possible to directly measure the multipartite MKB
concurrences of pure states. This may provide an experimental verification of
our conjecture that for a Heisenberg XY chain of any even number of qubits, it
is always possible to obtain non-zero genuine multipartite entanglement at any
finite temperature by applying a sufficiently large magnetic field.


title:
Double Helicity Asymmetry of Inclusive pi0 Production in Polarized pp
  Collisions at sqrt(s)=62.4GeV

abstract:
  The proton spin structure is not understood yet and there has remained large
uncertainty on Delta g, the gluon spin contribution to the proton. Double
helicity asymmetry (A_LL) of pi0 production in polarized pp collisions is used
to constrain Delta g. In this report, preliminary results of A_LL of pi0 in pp
collisions at sqrt(s) = 62.4 GeV measured by PHENIX experiment in 2006 is
presented. It can probe higer x region than the previously reported pi0 A_LL at
sqrt(s) = 200 GeV thanks to the lower center of mass energy.


title: Time dependence of joint entropy of oscillating quantum systems

abstract:
  The time dependent entropy (or Leipnik's entropy) of harmonic and damped
harmonic oscillators is extensively investigated by using time dependent wave
function obtained by the Feynman path integral method. Our results for simple
harmonic oscillator are in agrement with the literature. However, the joint
entropy of damped harmonic oscillator shows remarkable discontinuity with time
for certain values of damping factor. According to the results, the envelop of
the joint entropy curve increases with time monotonically. This results is the
general properties of the envelop of the joint entropy curve for quantum
systems.


title:
Tight bound on coherent states quantum key distribution with heterodyne
  detection

abstract:
  We propose a new upper bound for the eavesdropper's information in the direct
and reverse reconciliated coherent states quantum key distribution protocols
with heterodyne detection. This bound is derived by maximizing the leaked
information over the symplectic group of transformations that spans every
physical Gaussian attack on individual pulses. We exhibit four different
attacks that reach this bound, which shows that this bound is tight. Finally,
we compare the secret key rate obtained with this new bound to the homodyne
rate.


title:
Gaussian estimates for fundamental solutions of second order parabolic
  systems with time-independent coefficients

abstract:
  Auscher, McIntosh and Tchamitchian studied the heat kernels of second order
elliptic operators in divergence form with complex bounded measurable
coefficients on $\mathbb{R}^n$. In particular, in the case when $n=2$ they
obtained Gaussian upper bound estimates for the heat kernel without imposing
further assumption on the coefficients. We study the fundamental solutions of
the systems of second order parabolic equations in the divergence form with
bounded, measurable, time-independent coefficients, and extend their results to
the systems of parabolic equations.


title:
A Language-Based Approach for Improving the Robustness of Network
  Application Protocol Implementations

abstract:
  The secure and robust functioning of a network relies on the defect-free
implementation of network applications. As network protocols have become
increasingly complex, however, hand-writing network message processing code has
become increasingly error-prone. In this paper, we present a domain-specific
language, Zebu, for describing protocol message formats and related processing
constraints. From a Zebu specification, a compiler automatically generates
stubs to be used by an application to parse network messages. Zebu is easy to
use, as it builds on notations used in RFCs to describe protocol grammars. Zebu
is also efficient, as the memory usage is tailored to application needs and
message fragments can be specified to be processed on demand. Finally,
Zebu-based applications are robust, as the Zebu compiler automatically checks
specification consistency and generates parsing stubs that include validation
of the message structure. Using a mutation analysis in the context of SIP and
RTSP, we show that Zebu significantly improves application robustness.


title: A Close Look at Star Formation around Active Galactic Nuclei

abstract:
  We analyse star formation in the nuclei of 9 Seyfert galaxies at spatial
resolutions down to 0.085arcsec, corresponding to length scales of less than
10pc in some objects. Our data were taken mostly with the near infrared
adaptive optics integral field spectrograph SINFONI. The stellar light profiles
typically have size scales of a few tens of parsecs. In two cases there is
unambiguous kinematic evidence for stellar disks on these scales. In the
nuclear regions there appear to have been recent - but no longer active -
starbursts in the last 10-300Myr. The stellar luminosity is less than a few
percent of the AGN in the central 10pc, whereas on kiloparsec scales the
luminosities are comparable. The surface stellar luminosity density follows a
similar trend in all the objects, increasing steadily at smaller radii up to
10^{13}L_sun/kpc^2 in the central few parsecs, where the mass surface density
exceeds 10^4M_sun/pc^2. The intense starbursts were probably Eddington limited
and hence inevitably short-lived, implying that the starbursts occur in
multiple short bursts. The data hint at a delay of 50--100Myr between the onset
of star formation and subsequent fuelling of the black hole. We discuss whether
this may be a consequence of the role that stellar ejecta could play in
fuelling the black hole. While a significant mass is ejected by OB winds and
supernovae, their high velocity means that very little of it can be accreted.
On the other hand winds from AGB stars ultimately dominate the total mass loss,
and they can also be accreted very efficiently because of their slow speeds.


title: Decrease of entanglement by local operations in the D\"ur-Cirac method

abstract:
  One cannot always obtain information about entanglement by the D\"ur-Cirac
(DC) method. The impracticality is attributed to the decrease of entanglement
by local operations in the DC method. We show that, even in 2--qubit systems,
there exist states whose entangled property the DC method never evaluates. The
class of such states in 2--qubit systems is completely characterized by the
value of the fully entangled fraction. Actually, a state whose fully entangled
fraction is less than or equal to 1/2 is always transformed into a separable
state by local operations in the DC method, even if it has negative partial
transposition.


title:
Compton-thick AGN and the Synthesis of the Cosmic X-ray Background: the
  Suzaku Perspective

abstract:
  We discuss the abundance of Compton-thick AGN as estimated by the most recent
population synthesis models of the cosmic X-ray background. Only a small
fraction of these elusive objects have been detected so far, in line with the
model expectations. The advances expected by the broad band detectors on board
Suzaku are briefly reviewed.


title:
Kibble-Zurek mechanism in a quenched ferromagnetic Bose-Einstein
  condensate

abstract:
  The spin vortices are shown to be created through the Kibble-Zurek (KZ)
mechanism in a quantum phase transition of a spin-1 ferromagnetic Bose-Einstein
condensate, when the applied magnetic field is quenched below a critical value.
It is shown that the magnetic correlation functions have finite correlation
lengths, and magnetizations at widely separated positions grow in random
directions, resulting in spin vortices. We numerically confirm the scaling law
that the winding number of spin vortices is proportional to the square root of
the length of the closed path, and for slow quench, proportional to $\tau_{\rm
Q}^{-1/6}$ with $\tau_{\rm Q}$ being the quench time. The relation between the
spin conservation and the KZ mechanism is discussed.


title: Triangulated categories without models

abstract:
  We exhibit examples of triangulated categories which are neither the stable
category of a Frobenius category nor a full triangulated subcategory of the
homotopy category of a stable model category. Even more drastically, our
examples do not admit any non-trivial exact functors to or from these algebraic
respectively topological triangulated categories.


title: U-max-Statistics

abstract:
  In 1948, W. Hoeffding introduced a large class of unbiased estimators called
U-statistics, defined as the average value of a real-valued k-variate function
h calculated at all possible sets of k points from a random sample. In the
present paper we investigate the corresponding extreme value analogue, which we
shall call U-max-statistics. We are concerned with the behavior of the largest
value of such function h instead of its average. Examples of U-max-statistics
are the diameter or the largest scalar product within a random sample.
U-max-statistics of higher degrees are given by triameters and other metric
invariants.


title:
Dependence of exciton transition energy of single-walled carbon
  nanotubes on surrounding dielectric materials

abstract:
  We theoretically investigate the dependence of exciton transition energies on
dielectric constant of surrounding materials. We make a simple model for the
relation between dielectric constant of environment and a static dielectric
constant describing the effects of electrons in core states, $\sigma$ bonds and
surrounding materials. Although the model is very simple, calculated results
well reproduce experimental transition energy dependence on dielectric constant
of various surrounding materials.


title:
Mpemba effect and phase transitions in the adiabatic cooling of water
  before freezing

abstract:
  An accurate experimental investigation on the Mpemba effect (that is, the
freezing of initially hot water before cold one) is carried out, showing that
in the adiabatic cooling of water a relevant role is played by supercooling as
well as by phase transitions taking place at 6 +/- 1 oC, 3.5 +/- 0.5 oC and 1.3
+/- 0.6 oC, respectively. The last transition, occurring with a non negligible
probability of 0.21, has not been detected earlier. Supported by the
experimental results achieved, a thorough theoretical analysis of supercooling
and such phase transitions, which are interpreted in terms of different
ordering of clusters of molecules in water, is given.


title: Effects of atomic interactions on Quantum Accelerator Modes

abstract:
  We consider the influence of the inclusion of interatomic interactions on the
delta-kicked accelerator model. Our analysis concerns in particular quantum
accelerator modes, namely quantum ballistic transport near quantal resonances.
The atomic interaction is modelled by a Gross-Pitaevskii cubic nonlinearity,
and we address both attractive (focusing) and repulsive (defocusing) cases. The
most remarkable effect is enhancement or damping of the accelerator modes,
depending on the sign of the nonlinear parameter. We provide arguments showing
that the effect persists beyond mean-field description, and lies within the
experimentally accessible parameter range.


title: How far is it to a sudden future singularity of pressure?

abstract:
  We discuss the constraints coming from current observations of type Ia
supernovae on cosmological models which allow sudden future singularities of
pressure (with the scale factor and the energy density regular). We show that
such a sudden singularity may happen in the very near future (e.g. within ten
million years) and its prediction at the present moment of cosmic evolution
cannot be distinguished, with current observational data, from the prediction
given by the standard quintessence scenario of future evolution. Fortunately,
sudden future singularities are characterized by a momentary peak of infinite
tidal forces only; there is no geodesic incompletness which means that the
evolution of the universe may eventually be continued throughout until another
``more serious'' singularity such as Big-Crunch or Big-Rip.


title: Generalizing circles over algebraic extensions

abstract:
  This paper deals with a family of spatial rational curves that were
introduced by Andradas, Recio and Sendra, under the name of hypercircles, as an
algorithmic cornerstone tool in the context of improving the rational
parametrization (simplifying the coefficients of the rational functions, when
possible) of algebraic varieties. A real circle can be defined as the image of
the real axis under a Moebius transformation in the complex field. Likewise,
and roughly speaking, a hypercircle can be defined as the image of a line ("the
${\mathbb{K}}$-axis") in a $n$-degree finite algebraic extension
$\mathbb{K}(\alpha)\thickapprox\mathbb{K}^n$ under the transformation
$\frac{at+b}{ct+d}:\mathbb{K}(\alpha)\to\mathbb{K}(\alpha)$.
  The aim of this article is to extend, to the case of hypercircles, some of
the specific properties of circles. We show that hypercircles are precisely,
via $\mathbb{K}$-projective transformations, the rational normal curve of a
suitable degree. We also obtain a complete description of the points at
infinity of these curves (generalizing the cyclic structure at infinity of
circles). We characterize hypercircles as those curves of degree equal to the
dimension of the ambient affine space and with infinitely many
${\mathbb{K}}$-rational points, passing through these points at infinity.
Moreover, we give explicit formulae for the parametrization and implicitation
of hypercircles. Besides the intrinsic interest of this very special family of
curves, the understanding of its properties has a direct application to the
simplification of parametrizations problem, as shown in the last section.


title:
Decreasing families of dynamically determined intervals in the power-law
  family

abstract:
  We study the rate of growth of ratios of intervals delimited by the
post-critical orbit of a map in the quasi-quadratic family $x\mapsto
-|x|^\alpha +a.$ The critical order $\alpha$ is an arbitrary real number
$\alpha>1.$ The range of the parameter $a$ is confined to an interval
$(1,a_{\alpha})$ of length depending on the critical order. We prove that in
every power-law family there is a unique parameter $p_{\alpha}$ corresponding
to the kneading sequence $RLRRRLRC.$ Subsequently, we obtain monotonicity
results concerning ratios of all intervals labeled by infinite post-critical
orbit in the case of the kneading sequence $RLRL...$ This extends the results
from \cite{P}, via refinement of the tools based on special properties of
power-law mappings in non-euclidean metric.


title:
Disorder effect on the Friedel oscillations in a one-dimensional Mott
  insulator

abstract:
  The Friedel oscillations resulting from coupling a quantum dot to one edge of
a disordered one-dimensional wire in the Mott insulator regime, are calculated
numerically using the DMRG method. By investigating the influence of the
disorder on the Friedel oscillations decay we find that the effect of disorder
is reduced by increasing the interaction strength. This behavior is opposite to
the recently reported influence of disorder in the Anderson insulator regime,
where disorder led to a stronger decay of the Friedel oscillations.


title: Description of the Scenario Machine

abstract:
  We present here an updated description of the "Scenario Machine" code. This
tool is used to carry out a population synthesis of binary stars. Previous
version of the description can be found at
http://xray.sai.msu.ru/~mystery//articles/review/contents.html


title:
Why do some intermediate polars show soft X-ray emission? A survey of
  XMM-Newton spectra

abstract:
  We make a systematic analysis of the XMM-Newton X-ray spectra of intermediate
polars (IPs) and find that, contrary to the traditional picture, most show a
soft blackbody component. We compare the results with those from AM Her stars
and deduce that the blackbody emission arises from reprocessing of hard X-rays,
rather than from the blobby accretion sometimes seen in AM Hers. Whether an IP
shows a blackbody component appears to depend primarily on geometric factors: a
blackbody is not seen in those that have accretion footprints that are always
obscured by accretion curtains or are only visible when foreshortened on the
white-dwarf limb. Thus we argue against previous suggestions that the blackbody
emission characterises a separate sub-group of IPs which are more akin to AM
Hers, and develop a unified picture of the blackbody emission in these stars.


title:
Gutzwiller description of non-magnetic Mott insulators: a dimer lattice
  model

abstract:
  We introduce a novel extension of the Gutzwiller variational wavefunction
able to deal with insulators that escape any mean-field like description, as
for instance non-magnetic insulators. As an application, we study the Mott
transition from a paramagnetic metal into a non-magnetic Peierls, or
valence-bond, Mott insulator. We analyze this model by means of our Gutzwiller
wavefunction analytically in the limit of large coordination lattices, where we
find that: (1) the Mott transition is first order; (2) the Peierls gap is large
in the Mott insulator, although it is mainly contributed by the electron
repulsion; (3) singlet-superconductivity arises around the transition.


title: Velocity oscillations in actin-based motility

abstract:
  We present a simple and generic theoretical description of actin-based
motility, where polymerization of filaments maintains propulsion. The dynamics
is driven by polymerization kinetics at the filaments' free ends, crosslinking
of the actin network, attachment and detachment of filaments to the obstacle
interfaces and entropic forces. We show that spontaneous oscillations in the
velocity emerge in a broad range of parameter values, and compare our findings
with experiments.


title: Path integrals for stiff polymers applied to membrane physics

abstract:
  Path integrals similar to those describing stiff polymers arise in the
Helfrich model for membranes. We show how these types of path integrals can be
evaluated and apply our results to study the thermodynamics of a minority
stripe phase in a bulk membrane. The fluctuation induced contribution to the
line tension between the stripe and the bulk phase is computed, as well as the
effective interaction between the two phases in the tensionless case where the
two phases have differing bending rigidities.


title: Measuring CP violation in Bs->phi phi with LHCb

abstract:
  Sensitivity studies to the CP-violating parameters of the decay Bs->phi phi
with the LHCb experiment are presented. The decay proceeds via a b->s s anti-s
gluonic-penguin quark transition, which is sensitive to contributions from
beyond the Standard Model particles. A time-dependent angular analysis of
simulated data leads to an expected statistical uncertainty of 6 degrees on any
new physics induced CP-violating phase for a sample corresponding to 2 fb^{-1}
of integrated luminosity. The expected precision on sin2beta from the related
decay Bd->phi K0S is also discussed.


title:
A Panchromatic Study of the Globular Cluster NGC 1904. I: The Blue
  Straggler Population

abstract:
  By combining high-resolution (HST-WFPC2) and wide-field ground based (2.2m
ESO-WFI) and space (GALEX) observations, we have collected a multi-wavelength
photometric data base (ranging from the far UV to the near infrared) of the
galactic globular cluster NGC1904 (M79). The sample covers the entire cluster
extension, from the very central regions up to the tidal radius. In the present
paper such a data set is used to study the BSS population and its radial
distribution. A total number of 39 bright ($m_{218}\le 19.5$) BSS has been
detected, and they have been found to be highly segregated in the cluster core.
No significant upturn in the BSS frequency has been observed in the outskirts
of NGC 1904, in contrast to other clusters (M 3, 47 Tuc, NGC 6752, M 5) studied
with the same technique. Such evidences, coupled with the large radius of
avoidance estimated for NGC 1904 ($r_{avoid}\sim 30$ core radii), indicate that
the vast majority of the cluster heavy stars (binaries) has already sunk to the
core. Accordingly, extensive dynamical simulations suggest that BSS formed by
mass transfer activity in primordial binaries evolving in isolation in the
cluster outskirts represent only a negligible (0--10%) fraction of the overall
population.


title: Calculating Valid Domains for BDD-Based Interactive Configuration

abstract:
  In these notes we formally describe the functionality of Calculating Valid
Domains from the BDD representing the solution space of valid configurations.
The formalization is largely based on the CLab configuration framework.


title: Higgs and Z' Phenomenology in B-L extension of the Standard Model at LHC

abstract:
  The phenomenology of the low scale U(1)_{B-L} extension of the standard model
and its implications at LHC is presented. In this model, an extra gauge boson
corresponding to B-L gauge symmetry and an extra SM singlet scalar (heavy
Higgs) are predicted. We show a detailed analysis of both heavy and light
Higgses decay and production in addition to the possible decay channels of the
new gauge boson. We find that the cross sections of the SM-like Higgs
production are reduced by ~ 20%-30%, while its decay branching ratios remain
intact. The extra Higgs has relatively small cross sections and the branching
ratios of Z'-> l^+ l^- are of order ~20% compared to ~ 3% of the SM resuls.
Hence, the search for Z' is accessible via a clean dilepton signal at LHC.


title: What Can be Learned Studying the Distribution of the Biggest Fragment ?

abstract:
  In the canonical formalism of statistical physics, a signature of a first
order phase transition for finite systems is the bimodal distribution of an
order parameter. Previous thermodynamical studies of nuclear sources produced
in heavy-ion collisions provide information which support the existence of a
phase transition in those finite nuclear systems. Some results suggest that the
observable Z1 (charge of the biggest fragment) can be considered as a reliable
order parameter of the transition. This talk will show how from peripheral
collisions studied with the INDRA detector at GSI we can obtain this bimodal
behaviour of Z1. Getting rid of the entrance channel effects and under the
constraint of an equiprobable distribution of excitation energy (E*), we use
the canonical description of a phase transition to link this bimodal behaviour
with the residual convexity of the entropy. Theoretical (with and without phase
transition) and experimental Z1-E* correlations are compared. This comparison
allows us to rule out the case without transition. Moreover that quantitative
comparison provides us with information about the coexistence region in the
Z1-E* plane which is in good agreement with that obtained with the signal of
abnormal uctuations of configurational energy (microcanonical negative heat
capacity).


title:
The p-adic generalized twisted (h,q)-euler-l-function and its
  applications

abstract:
  The purpose of this paper is to construct the p-adic twisted
(h,q)-Euler-l-function, which interpolates the twisted generalized twisted
Euler numbers attached to chi at a negative integer.


title: Global coronal seismology

abstract:
  Following the observation and analysis of large-scale coronal wave-like
disturbances, we discuss the theoretical progress made in the field of global
coronal seismology. Using simple mathematical techniques we determine average
values for magnetic field together with a magnetic map of the quiet Sun. The
interaction between global coronal waves and coronal loops allows us to study
loop oscillations in a much wider context, i.e. we connect global and local
coronal oscillations.


title: La formule de Lie-Trotter pour les semi-groupes fortement continus

abstract:
  In this research project we presents the general properties, the spectral
properties and the representation formulas for $C_0$-semigroups of linear
operators in Banach spaces


title: Reconstructing the Intrinsic Triaxial Shape of the Virgo Cluster

abstract:
  To use galaxy clusters as a cosmological probe, it is important to account
for their triaxiality. Assuming that the triaxial shapes of galaxy clusters are
induced by the tidal interaction with the surrounding matter, Lee and Kang
recently developed a reconstruction algorithm for the measurement of the axial
ratio of a triaxial cluster. We examine the validity of this reconstruction
algorithm by performing an observational test of it with the Virgo cluster as a
target. We first modify the LK06 algorithm by incorporating the two dimensional
projection effect. Then, we analyze the 1275 member galaxies from the Virgo
Cluster Catalogue and find the projected direction of the Virgo cluster major
axis by measuring the anisotropy in the spatial distribution of the member
galaxies in the two dimensional projected plane. Applying the modified
reconstruction algorithm to the analyzed data, we find that the axial ratio of
the triaxial Virgo cluster is (1: 0.54 : 0.73). This result is consistent with
the recent observational report from the Virgo Cluster Survey, proving the
robustness of the reconstruction algorithm. It is also found that at the inner
radii the shape tends to be more like prolate. We discuss the possible effect
of the Virgo cluster triaxiality on the mass estimation.


title:
Flat Pencils of Symplectic Connections and Hamiltonian Operators of
  Degree 2

abstract:
  Bi-Hamiltonian structures involving Hamiltonian operators of degree 2 are
studied. Firstly, pairs of degree 2 operators are considered in terms of an
algebra structure on the space of 1-forms, related to so-called Fermionic
Novikov algebras. Then, degree 2 operators are considered as deformations of
hydrodynamic type Poisson brackets.


title:
IR-active optical phonons in Pnma-1, Pnma-2 and R3c phases of
  LaMnO_{3+\delta}

abstract:
  Infrared-active phonons in LaMnO_{3+\delta} were studied by means of the
reflection and transmission spectroscopy from 50 to 800 cm^{-1} at room
temperature. Powder and ceramic samples of the phases of Pnma-2 (\delta=0.02),
Pnma-1 (\delta=0.08), and R3c (\delta=0.15) were investigated. Besides,
energies of the dipole-active phonons in Pnma-2, Pnma-1 phases were obtained by
lattice-dynamics calculations. The transformations of IR-active phonons with
the increase of \delta in the sequence of Pnma-2, Pnma-1, R3c are discussed.


title: Equivalences of Higher Derived Brackets

abstract:
  This note elaborates on Th. Voronov's construction
[math/0304038,math/0412202] of $L_\infty$-structures via higher derived
brackets with a Maurer-Cartan element. It is shown that gauge equivalent
Maurer-Cartan elements induce $L_\infty$-isomorphic structures. Applications in
symplectic, Poisson and Dirac geometry are discussed.


title: Neutron matter from low-momentum interactions

abstract:
  We present a perturbative calculation of the neutron matter equation of state
based on low-momentum two- and three-nucleon interactions. Our results are
compared to the model-independent virial equation of state and to variational
calculations, and we provide theoretical error estimates by varying the cutoff
used to regulate nuclear interactions. In addition, we study the dependence of
the BCS $^1$S$_0$ superfluid pairing gap on nuclear interactions and on the
cutoff. The resulting gaps are well constrained by the nucleon-nucleon
scattering phase shifts, and the cutoff dependence is very weak for sharp or
sufficiently narrow smooth regulators with cutoffs $\lm > 1.6 \fmi$.


title: Euclidean analysis of the entropy functional formalism

abstract:
  The attractor mechanism implies that the supersymmetric black hole near
horizon solution is defined only in terms of the conserved charges and is
therefore independent of asymptotic moduli. Starting only with the near horizon
geometry, Sen's entropy functional formalism computes the entropy of an extreme
black hole by means of a Legendre transformation where the electric fields are
defined as conjugated variables to the electric charges. However, traditional
Euclidean methods require the knowledge of the full geometry to compute the
black hole thermodynamic quantities. We establish the connection between the
entropy functional formalism and the standard Euclidean formalism taken at zero
temperature. We find that Sen's entropy function 'f' (on-shell) matches the
zero temperature limit of the Euclidean action. Moreover, Sen's near horizon
angular and electric fields agree with the chemical potentials that are defined
from the zero-temperature limit of the Euclidean formalism.


title: On the existence of chaotic circumferential waves in spinning disks

abstract:
  We use a third-order perturbation theory and Melnikov's method to prove the
existence of chaos in spinning circular disks subject to a lateral point load.
We show that the emergence of transverse homoclinic and heteroclinic points
respectively lead to a random reversal in the traveling direction of
circumferential waves and a random phase shift of magnitude $\pi$ for both
forward and backward wave components. These long-term phenomena occur in
imperfect low-speed disks sufficiently far from fundamental resonances.


title:
First principles theory of chiral dichroism in electron microscopy
  applied to 3d ferromagnets

abstract:
  Recently it was demonstrated (Schattschneider et al., Nature 441 (2006),
486), that an analogue of the X-ray magnetic circular dichroism (XMCD)
experiment can be performed with the transmission electron microscope (TEM).
The new phenomenon has been named energy-loss magnetic chiral dichroism (EMCD).
In this work we present a detailed ab initio study of the chiral dichroism in
the Fe, Co and Ni transition elements. We discuss the methods used for the
simulations together with the validity and accuracy of the treatment, which
can, in principle, apply to any given crystalline specimen. The dependence of
the dichroic signal on the sample thickness, accuracy of the detector position
and the size of convergence and collection angles is calculated.


title:
Probing MACHOs by observation of M31 pixel lensing with the 1.5m Loiano
  telescope

abstract:
  We analyse a series of pilot observations in order to study microlensing of
(unresolved) stars in M31 with the 1.5m Loiano telescope, including
observations on both identified variable source stars and reported microlensing
events. We also look for previously unknown variability and discover a nova. We
discuss an observing strategy for an extended campaign with the goal of
determining whether MACHOs exist or whether all microlensing events are
compatible with lens stars in M31.


title: Preconditioned Temporal Difference Learning

abstract:
  This paper has been withdrawn by the author. This draft is withdrawn for its
poor quality in english, unfortunately produced by the author when he was just
starting his science route. Look at the ICML version instead:
http://icml2008.cs.helsinki.fi/papers/111.pdf


title:
QCD thermodynamics and confinement from a dynamical quasiparticle point
  of view

abstract:
  In this study it is demonstrated that a simple picture of the
  QCD gluon liquid emerges in the dynamical quasiparticle model that specifies
the active degrees of freedom in the time-like sector and yields a potential
energy density in the space-like sector. By using the time-like gluon density
(or scalar gluon density) as an independent degree of freedom - instead of the
temperature $T$ as a Lagrange parameter - variations of the potential energy
density lead to effective mean-fields for time-like gluons and an effective
gluon-gluon interaction strength at low density. The latter yields a simple
dynamical picture for the gluon fusion to color neutral glueballs when
approaching the phase boundary from a temperature higher than $T_c$ and paves
the way for an off-shell transport theoretical description of the parton
dynamics.


title:
Trellis-Coded Quantization Based on Maximum-Hamming-Distance Binary
  Codes

abstract:
  Most design approaches for trellis-coded quantization take advantage of the
duality of trellis-coded quantization with trellis-coded modulation, and use
the same empirically-found convolutional codes to label the trellis branches.
This letter presents an alternative approach that instead takes advantage of
maximum-Hamming-distance convolutional codes. The proposed source codes are
shown to be competitive with the best in the literature for the same
computational complexity.


title:
Dynamic fracture of icosahedral model quasicrystals: A molecular
  dynamics study

abstract:
  Ebert et al. [Phys. Rev. Lett. 77, 3827 (1996)] have fractured icosahedral
Al-Mn-Pd single crystals in ultrahigh vacuum and have investigated the cleavage
planes in-situ by scanning tunneling microscopy (STM). Globular patterns in the
STM-images were interpreted as clusters of atoms. These are significant
structural units of quasicrystals. The experiments of Ebert et al. imply that
they are also stable physical entities, a property controversially discussed
currently. For a clarification we performed the first large scale fracture
simulations on three-dimensional complex binary systems. We studied the
propagation of mode I cracks in an icosahedral model quasicrystal by molecular
dynamics techniques at low temperature. In particular we examined how the shape
of the cleavage plane is influenced by the clusters inherent in the model and
how it depends on the plane structure. Brittle fracture with no indication of
dislocation activity is observed. The crack surfaces are rough on the scale of
the clusters, but exhibit constant average heights for orientations
perpendicular to high symmetry axes. From detailed analyses of the fractured
samples we conclude that both, the plane structure and the clusters, strongly
influence dynamic fracture in quasicrystals and that the clusters therefore
have to be regarded as physical entities.


title:
Preparation and detection of magnetic quantum phases in optical
  superlattices

abstract:
  We describe a novel approach to prepare, detect and characterize magnetic
quantum phases in ultra-cold spinor atoms loaded in optical superlattices. Our
technique makes use of singlet-triplet spin manipulations in an array of
isolated double well potentials in analogy to recently demonstrated quantum
control in semiconductor quantum dots. We also discuss the many-body
singlet-triplet spin dynamics arising from coherent coupling between nearest
neighbor double wells and derive an effective description for such system. We
use it to study the generation of complex magnetic states by adiabatic and
non-equilibrium dynamics.


title:
Sobolev solution for semilinear PDE with obstacle under monotonicity
  condition

abstract:
  We prove the existence and uniqueness of the solution of a semilinear PDE's
and also PDE's with obstacle under monotonicity condition. Moreover we give the
probabilistic interpretation of the Sobolev's solutions in term of Backward SDE
and reflected Backward SDE respectively.


title:
Exact distribution of the sample variance from a gamma parent
  distribution

abstract:
  Several representations of the exact cdf of the sum of squares of n
independent gamma-distributed random variables Xi are given, in particular by a
series of gamma distribution functions. Using a characterization of the gamma
distribution by Laha, an expansion of the exact distribution of the sample
variance is derived by a Taylor series approach with the former distribution as
its leading term. In particular for integer orders alpha some further series
are provided, including a convex combination of gamma distributions for alpha =
1 and nearly of this type for alpha > 1. Furthermore, some representations of
the distribution of the angle Phi between (X1,...,Xn) and (1,...,1) are given
by orthogonal series. All these series are based on the same sequence of easily
computed moments of cos(Phi).


title:
Framework for non-perturbative analysis of a Z(3)-symmetric effective
  theory of finite temperature QCD

abstract:
  We study a three dimensional Z(3)-symmetric effective theory of high
temperature QCD. The exact lattice-continuum relations, needed in order to
perform lattice simulations with physical parameters, are computed to order
O(a^0) in lattice perturbation theory. Lattice simulations are performed to
determine the phase structure of a subset of the parameter space.


title: Constraints on Regge models from perturbation theory

abstract:
  We study the constraints that the operator product expansion imposes on large
$N_c$ inspired QCD models for current-current correlators. We focus on the
constraints obtained by going beyond the leading-order parton computation. We
explicitly show that, assumed a given mass spectrum: linear Regge behavior in
$n$ (the principal quantum number) plus corrections in $1/n$, we can obtain the
logarithmic (and constant) behavior in $n$ of the decay constants within a
systematic expansion in $1/n$. Our example shows that it is possible to have
different large $n$ behavior for the vector and pseudo-vector mass spectrum and
yet comply with all the constraints from the operator product expansion.


title: Asymptotic stability at infinity for bidimensional Hurwitz vector fields

abstract:
  Let $X:U-->R^2$ be a differentiable vector field. Set $Spc(X)={eigenvalues of
DX(z) : z\in U}$. This $X$ is called Hurwitz if $Spc(X)\subset{z\in
C:\Re(z)<0}$. Suppose that $X$ is Hurwitz and $U\subset R^2$ is the complement
of a compact set. Then by adding to $X$ a constant $v$ one obtains that the
infinity is either an attractor or a repellor for $X+v.$


title:
Quantitative LEED I-V and ab initio study of the Si(111)-3x2-Sm surface
  structure and the missing half order spots in the 3x1 diffraction pattern

abstract:
  We have used Low Energy Electron Diffraction (LEED) I-V analysis and ab
initio calculations to quantitatively determine the honeycomb chain model
structure for the Si(111)-3x2-Sm surface. This structure and a similar 3x1
recontruction have been observed for many Alkali-Earth and Rare-Earth metals on
the Si(111) surface. Our ab initio calculations show that there are two almost
degenerate sites for the Sm atom in the unit cell and the LEED I-V analysis
reveals that an admixture of the two in a ratio that slightly favours the site
with the lower energy is the best match to experiment. We show that the I-V
curves are insensitive to the presence of the Sm atom and that this results in
a very low intensity for the half order spots which might explain the
appearance of a 3x1 LEED pattern produced by all of the structures with a 3x2
unit cell.


title: Renormalization of Hamiltonian QCD

abstract:
  We study to one-loop order the renormalization of QCD in the Coulomb gauge
using the Hamitonian formalism. Divergences occur which might require
counter-terms outside the Hamiltonian formalism, but they can be cancelled by a
redefinition of the Yang-Mills electric field.


title: What made GRBs 060505 and 060614?

abstract:
  Recent observations of two nearby SN-less long-duration gamma-ray bursts
(GRBs), which share no obvious characteristics in their prompt emission,
suggest a new phenomenological type of massive stellar death. Here we briefly
review the observational properties of these bursts and their proposed hosts,
and discuss whether a new GRB classification scheme is needed.


title:
A new, very massive modular Liquid Argon Imaging Chamber to detect low
  energy off-axis neutrinos from the CNGS beam. (Project MODULAr)

abstract:
  The paper is considering an opportunity for the CERN/GranSasso (CNGS)
neutrino complex, concurrent time-wise with T2K and NOvA, to search for
theta_13 oscillations and CP violation. Compared with large water Cherenkov
(T2K) and fine grained scintillators (NOvA), the LAr-TPC offers a higher
detection efficiency and a lower backgrounds, since virtually all channels may
be unambiguously recognized. The present proposal, called MODULAr, describes a
20 kt fiducial volume LAr-TPC, following very closely the technology developed
for the ICARUS-T60o, and is focused on the following activities, for which we
seek an extended international collaboration:
  (1) the neutrino beam from the CERN 400 GeV proton beam and an optimised horn
focussing, eventually with an increased intensity in the framework of the LHC
accelerator improvement program;
  (2) A new experimental area LNGS-B, of at least 50000 m3 at 10 km off-axis
from the main Laboratory, eventually upgradable to larger sizes. A location is
under consideration at about 1.2 km equivalent water depth;
  (3) A new LAr Imaging detector of at least 20 kt fiducial mass. Such an
increase in the volume over the current ICARUS T600 needs to be carefully
considered. It is concluded that a very large mass is best realised with a set
of many identical, independent units, each of 5 kt, "cloning" the technology of
the T600. Further phases may foresee extensions of MODULAr to meet future
physics goals.
  The experiment might reasonably be operational in about 4/5 years, provided a
new hall is excavated in the vicinity of the Gran Sasso Laboratory and adequate
funding and participation are made available.


title:
Momentum distributions in time-dependent density functional theory:
  Product phase approximation for non-sequential double ionization in strong
  laser fields

abstract:
  We investigate the possibility to deduce momentum space properties from
time-dependent density functional calculations. Electron and ion momentum
distributions after double ionization of a model Helium atom in a strong
few-cycle laser pulse are studied. We show that, in this case, the choice of
suitable functionals for the observables is considerably more important than
the choice of the correlation potential in the time-dependent Kohn-Sham
equations. By comparison with the solution of the time-dependent Schroedinger
equation, the insufficiency of functionals neglecting electron correlation is
demonstrated. We construct a functional of the Kohn-Sham orbitals, which in
principle yields the exact momentum distributions of the electrons and the ion.
The product-phase approximation is introduced, which reduces the problem of
approximating this functional significantly.


title: The Amadeus project at Dafne

abstract:
  The change of the hadron masses and hadron interactions in the nuclear medium
and the structure of cold dense hadronic matter are hot topics of hadron
physics today. These important, yet unsolved, problems will be the research
field of AMADEUS (Antikaonic Matter At DAFNE: Experiments with Unraveling
Spectroscopy) - new experiment proposal at DAFNE accelerator at LNF-INFN.
AMADEUS will search for antikaon-mediated deeply bound nuclear states produced
in helium by stopping K- from DAFNE, both in the formation and in the decay
processes.


title:
Measurements and analysis of the upper critical field $H_{c2}$ on an
  underdoped and overdoped $La_{2-x}Sr_xCuO_4$ compounds

abstract:
  The upper critical field $H_{c2}$ is one of the many non conventional
properties of high-$T_c$ cuprates. It is possible that the $H_{c2}(T)$
anomalies are due to the presence of inhomogeneities in the local charge
carrier density $\rho$ of the $CuO_2$ planes. In order to study this point, we
have prepared good quality samples of polycrystalline $La_{2-x}Sr_xCuO_{4}$
using the wet-chemical method, which has demonstrated to produce samples with a
better cation distribution. In particular, we have studied the temperature
dependence of the second critical field, $H_{c2}(T)$, through the magnetization
measurements on two samples with opposite average carrier concentration
($\rho_m=x$) and nearly the same critical temperature, namely $\rho_m = 0.08$
(underdoped) and $\rho_m = 0.25$ (overdoped). The results close to $T_c$ do not
follow the usual Ginzburg-Landau theory and are interpreted by a theory which
takes into account the influence of the inhomogeneities.


title: Thermal Hadronization and Hawking-Unruh Radiation in QCD

abstract:
  We conjecture that because of color confinement, the physical vacuum forms an
event horizon for quarks and gluons which can be crossed only by quantum
tunneling, i.e., through the QCD counterpart of Hawking radiation by black
holes. Since such radiation cannot transmit information to the outside, it must
be thermal, of a temperature determined by the chromodynamic force at the
confinement surface, and it must maintain color neutrality. We explore the
possibility that the resulting process provides a common mechanism for thermal
hadron production in high energy interactions, from $e^+e^-$ annihilation to
heavy ion collisions.


title: Photo-assisted shot noise in Coulomb interacting systems

abstract:
  We consider the fluctuations of the electrical current (shot noise) in the
presence of a voltage time-modulation. For a non-interacting metal, it is known
that the derivative of the photo-assisted noise has a staircase behavior. In
the presence of Coulomb interactions, we show that the photo-assisted noise
presents a more complex profile, in particular for the two following systems:
1) a two-dimensional electron gas in the fractional quantum Hall regime for
which we have obtained evenly spaced singularities in the noise derivative,
with a spacing related to the filling factor and, 2) a carbon nanotube for
which a smoothed staircase in the noise derivative is obtained.


title:
A unified projection formalism for the Al-Pd-Mn quasicrystal
  Xi-approximants and their metadislocations

abstract:
  The approximants xi, xi' and xi'_n of the quasicrystal Al-Mn-Pd display most
interesting plastic properties as for example phason-induced deformation
processes (Klein, H., Audier, M., Boudard, M., de Boissieu, M., Beraha, L., and
Duneau, M., 1996, Phil. Mag. A, 73, 309.) or metadislocations (Klein, H.,
Feuerbacher, M., Schall, P., and Urban, K., 1999, Phys. Rev. Lett., 82, 3468.).
Here we demonstrate that the phases and their deformed or defected states can
be described by a simple projection formalism in three-dimensional space - not
as usual in four to six dimensions. With the method we can interpret
microstructures observed with electron microscopy as phasonic phase boundaries.
Furthermore we determine the metadislocations of lowest energy and relate them
uniquely to experimentally observed ones. Since moving metadislocations in the
xi'-phase can create new phason-planes, we suggest a dislocation induced phase
transition from xi' to xi'_n. The methods developed in this paper can as well
be used for various other complex metallic alloys.


title: Light stops in the MSSM parameter space

abstract:
  We consider the regions of the MSSM parameter space where the top squarks
become light and even may be the LSP. This happens when the triple scalar
coupling A becomes very big compared to m_0. We show that in this case the
requirement that the LSP is neutral imposes noticeable constraint on the
parameter space excluding low m_0 and m_{1/2} similar to constraint from the
Higgs mass limit. In some cases these constraints overlap. This picture takes
place in a wide region of \tan\beta. In a narrow band close to the border line
the stops are long-lived particles and decay into quarks and neutralino
(chargino). The cross-section of their production at LHC via gluon fusion
mechanism in this region may reach a few pb.


title:
The blue plume population in dwarf spheroidal galaxies: genuine blue
  stragglers or young stellar population?

abstract:
  Abridged... Blue stragglers (BSS) are thought to be the product of either
primordial or collisional binary systems. In the context of dwarf spheroidal
galaxies it is hard to firmly disentangle a genuine BSS population from young
main sequence (MS) stars tracing a ~1-2 Gyr old star forming episode. Assuming
that their blue plume populations are made of BSS, we estimate the BSS
frequency for 8 Local Group non star-forming dwarf galaxies, using a
compilation of ground and space based photometry.
  Our results can be summarized as follows: (i) The BSS frequency in dwarf
galaxies, at any given Mv, is always higher than that in globular clusters of
similar luminosities; (ii) the BSS frequency for the lowest luminosity dwarf
galaxies is in excellent agreement with that observed in the Milky Way halo;
and most interestingly (iii) derive a statistically significant
anti-correlation between the BSS frequency and the galaxy Mv.
  The low density, almost collision-less, environments of our dwarf galaxy
sample allow us to infer (i) their very low dynamical evolution; (ii) a
negligible production of collisional BSS; and consequently (iii) that their
blue plumes are mainly made of primordial binaries. The dwarf galaxies
anti-correlation can be used as a discriminator: galaxies obeying the
anti-correlation are more likely to possess genuine primordial BSS rather than
young main sequence stars.


title: Generalized characteristic polynomials of graph bundles

abstract:
  In this paper, we find computational formulae for generalized characteristic
polynomials of graph bundles. We show that the number of spanning trees in a
graph is the partial derivative (at (0,1)) of the generalized characteristic
polynomial of the graph. Since the reciprocal of the Bartholdi zeta function of
a graph can be derived from the generalized characteristic polynomial of a
graph, consequently, the Bartholdi zeta function of a graph bundle can be
computed by using our computational formulae.


title: Some invariants of pretzel links

abstract:
  We show that nontrivial classical pretzel knots L(p,q,r) are hyperbolic with
eight exceptions which are torus knots. We find Conway polynomials of n-pretzel
links using a new computation tree. As applications, we compute the genera of
n-pretzel links using these polynomials and find the basket number of pretzel
links by showing that the genus and the canonical genus of a pretzel link are
the same.


title:
Exact retrospective Monte Carlo computation of arithmetic average Asian
  options

abstract:
  Taking advantage of the recent litterature on exact simulation algorithms
(Beskos, Papaspiliopoulos and Roberts) and unbiased estimation of the
expectation of certain fonctional integrals (Wagner, Beskos et al. and
Fearnhead et al.), we apply an exact simulation based technique for pricing
continuous arithmetic average Asian options in the Black and Scholes framework.
Unlike existing Monte Carlo methods, we are no longer prone to the
discretization bias resulting from the approximation of continuous time
processes through discrete sampling. Numerical results of simulation studies
are presented and variance reduction problems are considered.


title:
Rotationally-invariant slave-boson formalism and momentum dependence of
  the quasiparticle weight

abstract:
  We generalize the rotationally-invariant formulation of the slave-boson
formalism to multiorbital models, with arbitrary interactions, crystal fields,
and multiplet structure. This allows for the study of multiplet effects on the
nature of low-energy quasiparticles. Non-diagonal components of the matrix of
quasiparticle weights can be calculated within this framework. When combined
with cluster extensions of dynamical mean-field theory, this method allows us
to address the effects of spatial correlations, such as the generation of the
superexchange and the momentum dependence of the quasiparticle weight. We
illustrate the method on a two-band Hubbard model, a Hubbard model made of two
coupled layers, and a two-dimensional single-band Hubbard model (within a
two-site cellular dynamical mean-field approximation).


title: On the failure of subadditivity of the Wigner-Yanase entropy

abstract:
  It was recently shown by Hansen that the Wigner-Yanase entropy is, for
general states of quantum systems, not subadditive with respect to
decomposition into two subsystems, although this property is known to hold for
pure states. We investigate the question whether the weaker property of
subadditivity for pure states with respect to decomposition into more than two
subsystems holds. This property would have interesting applications in quantum
chemistry. We show, however, that it does not hold in general, and provide a
counterexample.


title: Symmetries and the cosmological constant puzzle

abstract:
  We outline the evaluation of the cosmological constant in the framework of
the standard field-theoretical treatment of vacuum energy and discuss the
relation between the vacuum energy problem and the gauge-group spontaneous
symmetry breaking. We suggest possible extensions of the 't Hooft-Nobbenhuis
symmetry, in particular, its complexification till duality symmetry and discuss
the compatible implementation on gravity. We propose to use the discrete
time-reflection transform to formulate a framework in which one can eliminate
the huge contributions of vacuum energy into the effective cosmological
constant and suggest that the breaking of time--reflection symmetry could be
responsible for a small observable value of this constant.


title:
The property of kappa-deformed statistics for a relativistic gas in an
  electromagnetic field: kappa parameter and kappa-distribution

abstract:
  We investigate the physical property of the kappa parameter and the
kappa-distribution in the kappa-deformed statistics, based on Kaniadakis
entropy, for a relativistic gas in an electromagnetic field. We derive two
relations for the relativistic gas in the framework of kappa-deformed
statistics, which describe the physical situation represented by the
relativistic kappa-distribution function, provide a reasonable connection
between the parameter kappa, the temperature four-gradient and the four-vector
potential gradient, and thus present for the case kappa different from zero a
clearly physical meaning. It is shown that such a physical situation is a
meta-equilibrium state of the system, but has a new physical characteristic.


title: A KK-monopole giant graviton in AdS_5 x Y_5

abstract:
  We construct a new giant graviton solution in AdS_5 x Y_5, with Y_5 a
quasi-regular Sasaki-Einstein manifold, consisting on a Kaluza-Klein monopole
wrapped around the Y_5 and with its Taub-NUT direction in AdS_5. We find that
this configuration has minimal energy when put in the centre of AdS_5, where it
behaves as a massless particle. When we take Y_5 to be S^5, we provide a
microscopical description in terms of multiple gravitational waves expanding
into the fuzzy S^5 defined as an S^1 bundle over the fuzzy CP^2. Finally we
provide a possible field theory dual interpretation of the construction.


title: Critical Behavior of a Trapped Interacting Bose Gas

abstract:
  The phase transition of Bose-Einstein condensation is studied in the critical
regime, when fluctuations extend far beyond the length scale of thermal de
Broglie waves. Using matter-wave interference we measure the correlation length
of these critical fluctuations as a function of temperature. The diverging
behavior of the correlation length above the critical temperature is observed,
from which we determine the critical exponent of the correlation length for a
trapped, weakly interacting Bose gas to be $\nu=0.67\pm 0.13$. This measurement
has direct implications for the understanding of second order phase
transitions.


title: Tiling models for metadislocations in AlPdMn approximants

abstract:
  The AlPdMn quasicrystal approximants xi, xi', and xi'_n of the 1.6 nm
decagonal phase and R, T, and T_n of the 1.2 nm decagonal phase can be viewed
as arrangements of cluster columns on two-dimensional tilings. We substitute
the tiles by Penrose rhombs and show, that alternative tilings can be
constructed by a simple cut and projection formalism in three dimensional
hyperspace. It follows that in the approximants there is a phasonic degree of
freedom, whose excitation results in the reshuffling of the clusters. We apply
the tiling model for metadislocations, which are special textures of partial
dislocations.


title:
Heisenberg antiferromagnet with anisotropic exchange on the Kagome
  lattice: Description of the magnetic properties of volborthite

abstract:
  We study the properties of the Heisenberg antiferromagnet with spatially
anisotropic nearest-neighbour exchange couplings on the kagome net, i.e. with
coupling J in one lattice direction and couplings J' along the other two
directions. For J/J' > 1, this model is believed to describe the magnetic
properties of the mineral volborthite. In the classical limit, it exhibits two
kinds of ground states: a ferrimagnetic state for J/J' < 1/2 and a large
manifold of canted spin states for J/J' > 1/2. To include quantum effects
self-consistently, we investigate the Sp(N) symmetric generalisation of the
original SU(2) symmetric model in the large-N limit. In addition to the
dependence on the anisotropy, the Sp(N) symmetric model depends on a parameter
kappa that measures the importance of quantum effects. Our numerical
calculations reveal that in the kappa-J/J' plane, the system shows a rich phase
diagram containing a ferrimagnetic phase, an incommensurate phase, and a
decoupled chain phase, the latter two with short- and long-range order. We
corroborate these results by showing that the boundaries between the various
phases and several other features of the Sp(N) phase diagram can be determined
by analytical calculations. Finally, the application of a block-spin
perturbation expansion to the trimerised version of the original spin-1/2 model
leads us to suggest that in the limit of strong anisotropy, J/J' >> 1, the
ground state of the original model is a collinearly ordered antiferromagnet,
which is separated from the incommensurate state by a quantum phase transition.


title:
On the Nature of Ultra-Luminous X-ray Sources from Optical/IR
  Measurements

abstract:
  We present a model for the prediction of the optical/infra-red emission from
ULXs. In the model, ULXs are binary systems with accretion taking place through
Roche lobe overflow. We show that irradiation effects and presence of an
accretion disk significantly modify the optical/infrared flux compared to
single stars, and also that the system orientation is important. We include
additional constraints from the mass transfer rate to constrain the parameters
of the donor star, and to a lesser extent the mass of the BH. We apply the
model to fit photometric data for several ULX counterparts. We find that most
donor stars are of spectral type B and are older and less massive than reported
elsewhere, but that no late-type donors are admissable. The degeneracy of the
acceptable parameter space will be significantly reduced with observations over
a wider spectral range, and if time-resolved data become available.


title: Dephasing due to a fluctuating fractional quantum Hall edge current

abstract:
  The dephasing rate of an electron level in a quantum dot, placed next to a
fluctuating edge current in the fractional quantum Hall effect, is considered.
Using perturbation theory, we first show that this rate has an anomalous
dependence on the bias voltage applied to the neighboring quantum point
contact, because of the Luttinger liquid physics which describes the fractional
Hall fluid. Next, we describe exactly the weak to strong backscattering
crossover using the Bethe-Ansatz solution.


title: Fracture of complex metallic alloys: An atomistic study of model systems

abstract:
  Molecular dynamics simulations of crack propagation are performed for two
extreme cases of complex metallic alloys (CMAs): In a model quasicrystal the
structure is determined by clusters of atoms, whereas the model C15 Laves phase
is a simple periodic stacking of a unit cell. The simulations reveal that the
basic building units of the structures also govern their fracture behaviour.
Atoms in the Laves phase play a comparable role to the clusters in the
quasicrystal. Although the latter are not rigid units, they have to be regarded
as significant physical entities.


title: Deformed Wigner crystal in a one-dimensional quantum dot

abstract:
  The spatial Fourier spectrum of the electron density distribution in a finite
1D system and the distribution function of electrons over single-particle
states are studied in detail to show that there are two universal features in
their behavior, which characterize the electron ordering and the deformation of
Wigner crystal by boundaries. The distribution function has a $\delta$-like
singularity at the Fermi momentum $k_F$. The Fourier spectrum of the density
has a step-like form at the wavevector $2k_F$, with the harmonics being absent
or vanishing above this threshold. These features are found by calculations
using exact diagonalization method. They are shown to be caused by Wigner
ordering of electrons, affected by the boundaries. However the common Luttinger
liquid model with open boundaries fails to capture these features, because it
overestimates the deformation of the Wigner crystal. An improvement of the
Luttinger liquid model is proposed which allows one to describe the above
features correctly. It is based on the corrected form of the density operator
conserving the particle number.


title: Curvature in Synthetic Differential Geometry of Groupoids

abstract:
  We study the fundamental properties of curvature in groupoids within the
framework of synthetic differential geometry. As is usual in synthetic
differential geometry, its combinatorial nature is emphasized. In particular,
the classical Bianchi identity is deduced from its combinatorial one.


title: Can Gravity Probe B usefully constrain torsion gravity theories?

abstract:
  In most theories of gravity involving torsion, the source for torsion is the
intrinsic spin of matter. Since the spins of fermions are normally randomly
oriented in macroscopic bodies, the torsion generated is normally negligible.
However, in a recent paper, Mao et al. point out that there is a class of
theories in which the angular momentum of macroscopic spinning bodies generates
a significant amount of torsion. They argue that by the principle of action
equals reaction, one would expect the angular momentum of test bodies to couple
to a background torsion field, and therefore the precession of the GPB
gyroscopes should be affected in these theories by the torsion generated by the
Earth. We show that in fact the principle of action equals reaction does not
apply to these theories. We examine in detail a generalization of the
Hayashi-Shirafuji theory suggested by Mao et al. called
Einstein-Hayashi-Shirafuji theory. There are a variety of different versions of
this theory, depending on the precise form of the coupling to matter chosen for
the torsion. We show that for any coupling to matter that is compatible with
the spin transport equation postulated by Mao et al., the theory has either
ghosts or an ill-posed initial value formulation. These theoretical problems
can be avoided by specializing the parameters of the theory and in addition
choosing the standard minimal coupling to matter of the torsion tensor. This
yields a consistent theory, but one in which the action equals reaction
principle is violated, and in which the angular momentum of the gyroscopes does
not couple to the Earth's torsion field. Thus, the Einstein-Hayashi-Shirafuji
theory does not predict a detectable torsion signal for Gravity Probe B. There
may be other torsion theories which do.


title: Structures in the Universe and Origin of Galaxies

abstract:
  The analysis of images (of obtained in various ranges of the lengths of
waves) of luminous objects in the Universe by means of a method of multilevel
dynamic contrasting led author to the conclusions: a) the structures of all
observable galaxies represents a complicated constructions which have the
tendency to self-similarity and made of separate (basic) blocks, which are a
coaxially tubular structures and a cartwheel-like structures; b) the majority
of observable objects in the Universe are luminous butt-ends of almost
invisible (of almost completely transparent) of filamentary formations which
structures are seen only near to their luminous butt-ends; c) the result of
analysis of images of cosmic objects show the structure of many pairs of
cooperating galaxies point to opportunity of their formation at butt-ends
generated in a place of break of the similar filament; d) the interacting
galaxies (M 81 and M 82) show they are butt-ends of sawed off of two branches
of a treelike filament and their interaction is coming out through this
filament; e) as our Universe is in dynamics the processes of formation of
stars, galaxies and their congestions can go presently by means of a fracturing
of filaments with a corresponding diameters and of the time for their such
formation is necessary much less, than along existing standard model.


title:
The classification ofseparable simple C*-algebras which are inductive
  limits of continuous-trace C*-algebraswith spectrum homeomorphic to the
  closed interval [0,1]

abstract:
  A classification is given of certain separable nuclear C*-algebras not
necessarily of real rank zero, namely, the class of separable simple
C*-algebras which are inductive limits of continuous-trace C*-algebras whose
building blocks have spectrum homeomorphic to the closed interval [0,1], or to
a disjoint union of copies of this space. Also, the range of the invariant is
calculated.


title:
U B V R I Photometry of Stellar Structures throughout the Disk of the
  Barred Galaxy NGC 3367

abstract:
  We report new detailed surface U, B, V, R, and I photometry of 81 stellar
structures in the disk of the barred galaxy NGC 3367. The images show many
different structures indicating that star formation is going on in the most
part of the disk. NGC 3367 is known to have a very high concentration of
molecular gas distribution in the central regions of the galaxy and bipolar
synchrotron emission from the nucleus with two lobes (at 6 kpc) forming a
triple structure similar to a radio galaxy. We have determined the U, B, V, R,
and I magnitudes and U - B, B - V, U - V, and V - I colors for the central
region (nucleus), a region which includes supernovae 2003 AA, and 79 star
associations throughout NGC 3367. Estimation of ages of star associations is
very difficult due to several factors, among them: filling factor, metallicity,
spatial distribution of each structure and the fact that we estimated the
magnitudes with a circular aperture of 16 pixels in diameter, equivalent to
$6''.8\sim1.4$ kpc. However, if the colors derived for NGC 3367 were similar to
the colors expected of star clusters with theoretical evolutionary star tracks
developed for the LMC and had a similar metallicity, NGC 3367 show 51 percent
of the observed structures with age type SWB I (few tens of Myrs), with seven
sources outside the bright surface brightness visible disk of NGC 3367.


title: Proton Decay Constraints on Low Scale AdS/CFT Unification

abstract:
  Dark matter candidates and proton decay in a class of models based on the
AdS/CFT correspondence are discussed. We show that the present bound on the
proton decay lifetime is inconsistent with ${\cal N} = 1$ SUSY, and strongly
constrains ${\cal N} = 0$ non-SUSY, low scale trinification type unification of
orbifolded AdS$\otimes S^5$ models.


title: BPS Black Holes

abstract:
  The entropy of BPS black holes in four space-time dimensions is discussed
from both macroscopic and microscopic points of view.


title:
Structure factors of harmonic and anharmonic Fibonacci chains by
  molecular dynamics simulations

abstract:
  The dynamics of quasicrystals is characterized by the existence of phason
excitations in addition to the usual phonon modes. In order to investigate
their interplay on an elementary level we resort to various one-dimensional
model systems. The main observables are the static, the incoherent, and the
coherent structure factor, which are extracted from molecular dynamics
simulations. For the validation of the algorithms, results for the harmonic
periodic chain are presented. We then study the Fibonacci chain with harmonic
and anharmonic interaction potentials. In the dynamic Fibonacci chain
neighboring atoms interact by double-well potentials allowing for phason flips.
The difference between the structure factors of the dynamic and the harmonic
Fibonacci chain lies in the temperature dependence of the phonon line width. If
a bias is introduced in the well depth, dispersionless optic phonon bands split
off.


title:
Ground-Based Direct Detection of Exoplanets with the Gemini Planet
  Imager (GPI)

abstract:
  The Gemini Planet (GPI) imager is an "extreme" adaptive optics system being
designed and built for the Gemini Observatory. GPI combines precise and
accurate wavefront control, diffraction suppression, and a speckle-suppressing
science camera with integral field and polarimetry capabilities. GPI's primary
science goal is the direct detection and characterization of young, Jovian-mass
exoplanets. For systems younger than 2 Gyr exoplanets more massive than 6 MJ
and semimajor axes beyond 10 AU are detected with completeness greater than
50%. GPI will also discover faint debris disks, explore icy moons and minor
planets in the solar system, reveal high dynamic range main-sequence binaries,
and study mass loss from evolved stars. This white paper explains the role of
GPI in exoplanet discovery and characterization and summarizes our
recommendations to the NSF-NASA-DOE Astronomy and Astrophysics Advisory
Committee ExoPlanet Task Force.


title: A Better Good-Turing Estimator for Sequence Probabilities

abstract:
  We consider the problem of estimating the probability of an observed string
drawn i.i.d. from an unknown distribution. The key feature of our study is that
the length of the observed string is assumed to be of the same order as the
size of the underlying alphabet. In this setting, many letters are unseen and
the empirical distribution tends to overestimate the probability of the
observed letters. To overcome this problem, the traditional approach to
probability estimation is to use the classical Good-Turing estimator. We
introduce a natural scaling model and use it to show that the Good-Turing
sequence probability estimator is not consistent. We then introduce a novel
sequence probability estimator that is indeed consistent under the natural
scaling model.


title:
Effective temperature vs line-depth ratio for ELODIE spectra. Gravity
  and rotational velocity effects

abstract:
  The dependence on the temperature of photospheric line-depth ratios (LDRs) in
the spectral range 6190-6280 A is investigated by using a sample of 174 ELODIE
Archive stellar spectra of luminosity class from V to III. The rotational
broadening effect on LDRs is also studied. We provide useful calibrations of
effective temperature versus LDRs for giant and main sequence stars with
3800<Teff<6000 K and vsini in the range 0-30 km/s. We found that, with the
exception of very few line pairs, LDRs, measured at a spectral resolution as
high as 42000, depend on vsini and that, by neglecting the rotational
broadening effect, one can mistake the Teff determination of 100 K in the worst
cases.


title: Chaos and Symmetry in String Cosmology

abstract:
  We review the recently discovered interplay between chaos and symmetry in the
general inhomogeneous solution of many string-related Einstein-matter systems
in the vicinity of a cosmological singularity. The
Belinsky-Khalatnikov-Lifshitz-type chaotic behaviour is found, for many
Einstein-matter models (notably those related to the low-energy limit of
superstring theory and M-theory), to be connected with certain
(infinite-dimensional) hyperbolic Kac-Moody algebras. In particular, the
billiard chambers describing the asymptotic cosmological behaviour of pure
Einstein gravity in spacetime dimension d+1, or the metric-three-form system of
11-dimensional supergravity, are found to be identical to the Weyl chambers of
the Lorentzian Kac-Moody algebras AE_d, or E_{10}, respectively. This suggests
that these Kac-Moody algebras are hidden symmetries of the corresponding
models. There even exists some evidence of a hidden equivalence between the
general solution of the Einstein-three-form system and a null geodesic in the
infinite dimensional coset space E_{10} / K(E_{10}), where K(E_{10}) is the
maximal compact subgroup of E_{10}.


title:
Radio Emission from the Intermediate-mass Black Hole in the Globular
  Cluster G1

abstract:
  We have used the Very Large Array (VLA) to search for radio emission from the
globular cluster G1 (Mayall-II) in M31. G1 has been reported by Gebhardt et al.
to contain an intermediate-mass black hole (IMBH) with a mass of ~2 x 10^4
solar masses. Radio emission was detected within an arcsecond of the cluster
center with an 8.4 GHz power of 2 x 10^{15} W/Hz. The radio/X-ray ratio of G1
is a few hundred times higher than that expected for a high-mass X-ray binary
in the cluster center, but is consistent with the expected value for accretion
onto an IMBH with the reported mass. A pulsar wind nebula is also a possible
candidate for the radio and X-ray emission from G1; future high-sensitivity
VLBI observations might distinguish between this possibility and an IMBH. If
the radio source is an IMBH, and similar accretion and outflow processes occur
for hypothesized ~ 1000-solar-mass black holes in Milky Way globular clusters,
they are within reach of the current VLA and should be detectable easily by the
Expanded VLA when it comes on line in 2010.


title: Even infinite dimensional real Banach spaces

abstract:
  This article is a continuation of a paper of the first author \cite{F} about
complex structures on real Banach spaces. We define a notion of even infinite
dimensional real Banach space, and prove that there exist even spaces,
including HI or unconditional examples from \cite{F} and $C(K)$ examples due to
Plebanek \cite{P}. We extend results of \cite{F} relating the set of complex
structures up to isomorphism on a real space to a group associated to
inessential operators on that space, and give characterizations of even spaces
in terms of this group. We also generalize results of \cite{F} about totally
incomparable complex structures to essentially incomparable complex structures,
while showing that the complex version of a space defined by S. Argyros and A.
Manoussakis \cite{AM} provide examples of essentially incomparable complex
structures which are not totally incomparable.


title: Landau-Lifshitz sigma-models, fermions and the AdS/CFT correspondence

abstract:
  We define Landau-Lifshitz sigma models on general coset space $G/H$, with $H$
a maximal stability sub-group of $G$. These are non-relativistic models that
have $G$-valued N\"other charges, local $H$ invariance and are classically
integrable. Using this definition, we construct the $PSU(2,2|4)/PS(U(2|2)^2)$
Landau-Lifshitz sigma-model. This sigma model describes the thermodynamic limit
of the spin-chain Hamiltonian obtained from the complete one-loop dilatation
operator of the N=4 super Yang-Mills (SYM) theory. In the second part of the
paper, we identify a number of consistent truncations of the Type IIB
Green-Schwarz action on $AdS_5\times S^5$ whose field content consists of two
real bosons and 4,8 or 16 real fermions. We show that $\kappa$-symmetry acts
trivially in these sub-sectors. In the context of the large spin limit of the
AdS/CFT correspondence, we map the Lagrangians of these sub-sectors to
corresponding truncations of the $PSU(2,2|4)/PS(U(2|2)^2)$ Landau-Lifshitz
sigma-model.


title: Trajectory of neutron$-$neutron$-^{18}C$ excited three-body state

abstract:
  The trajectory of the first excited Efimov state is investigated by using a
renormalized zero-range three-body model for a system with two bound and one
virtual two-body subsystems. The approach is applied to $n-n-^{18}$C, where the
$n-n$ virtual energy and the three-body ground state are kept fixed. It is
shown that such three-body excited state goes from a bound to a virtual state
when the $n-^{18}$C binding energy is increased. Results obtained for the
$n-^{19}$C elastic cross-section at low energies also show dominance of an
$S-$matrix pole corresponding to a bound or virtual Efimov state. It is also
presented a brief discussion of these findings in the context of ultracold atom
physics with tunable scattering lengths.