title:
Measurement of 25Mg(p; gamma)26Al resonance strengths via gamma
  spectrometry

abstract:
  The COMPTEL instrument performed the first mapping of the 1.809 MeV photons
in the Galaxy, triggering considerable interest in determing the sources of
interstellar 26Al. The predicted 26Al is too low compared to the observation,
for a better understanding more accurate rates for the 25Mg(p; gamma)26Al
reaction are required. The 25Mg(p;gamma)26Al reaction has been investigated at
the resonances at Er= 745; 418; 374; 304 keV at Ruhr-Universitat-Bochum using a
Tandem accelerator and a 4piNaI detector. In addition the resonance at Er = 189
keV has been measured deep underground laboratory at Laboratori Nazionali del
Gran Sasso, exploiting the strong suppression of cosmic background. This low
resonance has been studied with the 400 kV LUNA accelerator and a HPGe
detector. The preliminary results of the resonance strengths will be reported.


title:
Low degree bounded cohomology and l^2-invariants for negatively curved
  groups

abstract:
  We study the subgroup structure of discrete groups which share cohomological
properties which resemble non-negative curvature. Examples include all Gromov
hyperbolic groups.
  We provide strong restrictions on the possible s-normal subgroups of a Gromov
hyperbolic group, or more generally a 'negatively curved' group. Another result
says that the image of a group, which is boundedly generated by a finite set of
amenable subgroups, in a Gromov hyperbolic group has to be virtually cyclic.
Moreover, we show that any homomorphic image of an analogue of a higher rank
lattices in a Gromov hyperbolic group must be finite. These results extend to a
certain class of randomorphisms in the sense of Monod. We study the class of
groups which admit proper quasi-1-cocycles and show that it is closed under
l2-orbit equivalence.


title: Structure factor of Bose-condensed systems

abstract:
  The structure factor for a Bose system with Bose-Einstein condensate is
considered in the frame of the self-consistent mean-field approximation. The
accomplished analysis demonstrates the principal importance of the following
three points: the necessity of preserving the approximation order, the
necessity of taking into account anomalous averages, and the necessity of gauge
symmetry breaking. If any one of these necessary conditions is not satisfied,
calculations yield the appearance of unphysical divergences of the structure
factor, which implies the occurrence of fictitious instability, which
contradicts experiments.


title: Chow motives of universal families over some Shimura surfaces

abstract:
  We prove an absolute Chow-Kuenneth decomposition for the motive of universal
families A of abelian varieties over some compact Shimura surface. We
furthermore prove the Hodge conjecture for general fibres of A, extending
results of Ribet.


title:
Conductance of a tunnel point-contact of noble metals in the presence of
  a single defect

abstract:
  In paper [1] (Avotina et al. Phys. Rev. B,74, 085411 (2006)) the effect of
Fermi surface anisotropy to the conductance of a tunnel point contact, in the
vicinity of which a single point-like defect is situated, has been investigated
theoretically. The oscillatory dependence of the conductance on the distance
between the contact and the defect has been found for a general Fermi surface
geometry. In this paper we apply the method developed in [1] to the calculation
of the conductance of noble metal contacts. An original algorithm, which
enables the computation of the conductance for any parametrically given Fermi
surface, is proposed. On this basis a pattern of the conductance oscillations,
which can be observed by the method of scanning tunneling microscopy, is
obtained for different orientations of the surface for the noble metals.


title: Dispersion relations and QCD factorization in hard reactions

abstract:
  We study analytical properties of the hard exclusive process amplitudes. We
found that QCD factorization for deeply virtual Compton scattering and hard
exclusive vector meson production results in the subtracted dispersion relation
with the subtraction constant determined by the Polyakov-Weiss $D$-term.


title: $\pi N\to \eta N$ process in a $\chi$QM approach

abstract:
  A chiral quark model approach is used to investigate the $\pi^{-}p \to \eta
n$ process at low energies. The roles of the most relevant nucleon resonances
in $n\leq 2$ shells are briefly discussed.


title: On the Integrable Structure of the Ising Model

abstract:
  Starting from the lattice $A_3$ realization of the Ising model defined on a
strip with integrable boundary conditions, the exact spectrum (including
excited states) of all the local integrals of motion is derived in the
continuum limit by means of TBA techniques. It is also possible to follow the
massive flow of this spectrum between the UV $c=1/2$ conformal fixed point and
the massive IR theory. The UV expression of the eigenstates of such integrals
of motion in terms of Virasoro modes is found to have only rational
coefficients and their fermionic representation turns out to be simply related
to the quantum numbers describing the spectrum.


title: Typicality for Generalized Microcanonical Ensembles

abstract:
  For a macroscopic, isolated quantum system in an unknown pure state, the
expectation value of any given observable is shown to hardly deviate from the
ensemble average with extremely high probability under generic equilibrium and
nonequilibrium conditions. Special care is devoted to the uncontrollable
microscopic details of the system state. For a subsystem weakly coupled to a
large heat bath, the canonical ensemble is recovered under much more general
and realistic assumptions than those implicit in the usual microcanonical
description of the composite system at equilibrium.


title: On Majorana fermions on the lattice

abstract:
  The construction of massless Majorana fermions with chiral Yukawa couplings
on the lattice is considered. We find topological obstructions tightly linked
to those underlying the Nielsen-Ninomiya no-go theorem. In contradistinction to
chiral fermions the obstructions originate only from the combination of the
Dirac action and the Yukawa term. These findings are used to construct a
chirally invariant lattice action. We also show that the path intgral of this
theory is given by the Pfaffian of the corresponding Dirac operator.


title: Anomalous GPDs in the photon

abstract:
  We consider deeply virtual Compton scattering (DVCS) on a photon target, in
the generalized Bjorken limit, at the Born order and in the leading logarithmic
approximation. This leads us to the extraction of the photon anomalous
generalized parton distributions (GPDs) \cite{url, DVCSphoton}.


title:
Optimal rate of convergence for nonparametric change-point estimators
  for nonstationary sequences

abstract:
  Let $(X_i)_{i=1,...,n}$ be a possibly nonstationary sequence such that
$\mathscr{L}(X_i)=P_n$ if $i\leq n\theta$ and $\mathscr{L}(X_i)=Q_n$ if
$i>n\theta$, where $0<\theta <1$ is the location of the change-point to be
estimated. We construct a class of estimators based on the empirical measures
and a seminorm on the space of measures defined through a family of functions
$\mathcal{F}$. We prove the consistency of the estimator and give rates of
convergence under very general conditions. In particular, the $1/n$ rate is
achieved for a wide class of processes including long-range dependent sequences
and even nonstationary ones. The approach unifies, generalizes and improves on
the existing results for both parametric and nonparametric change-point
estimation, applied to independent, short-range dependent and as well
long-range dependent sequences.


title:
Foldy-Wouthyusen Transformation and Semiclassical Limit for Relativistic
  Particles in Strong External Fields

abstract:
  A general method of the Foldy-Wouthyusen (FW) transformation for relativistic
particles of arbitrary spin in strong external fields has been developed. The
use of the found transformation operator is not restricted by any definite
commutation relations between even and odd operators. The final FW Hamiltonian
can be expanded into a power series in the Planck constant which characterizes
the order of magnitude of quantum corrections. Exact expressions for low-order
terms in the Planck constant can be derived. Finding these expressions allows
to perform a simple transition to the semiclassical approximation which defines
a classical limit of the relativistic quantum mechanics. As an example,
interactions of spin-1/2 and scalar particles with a strong electromagnetic
field have been considered. Quantum and semiclassical equations of motion of
particles and their spins have been deduced. Full agreement between quantum and
classical theories has been established.


title:
Arithmetic of rationaly connected quintic 3-folds over finite and
  function fields

abstract:
  We prove that both classical Chevalley-Warning-Ax and Tsen theorems hold for
the blowing up of a quintic 3-fold along a line of multiplicity 3. Both proofs,
which are of the same spirit than the original ones, involve the description of
this blowing-up as a subvariety of a toric variety.


title: Ultracold atoms in optical lattices generated by quantized light fields

abstract:
  We study an ultracold gas of neutral atoms subject to the periodic optical
potential generated by a high-$Q$ cavity mode. In the limit of very low
temperatures, cavity field and atomic dynamics require a quantum description.
Starting from a cavity QED single atom Hamiltonian we use different routes to
derive approximative multiparticle Hamiltonians in Bose-Hubbard form with
rescaled or even dynamical parameters. In the limit of large enough cavity
damping the different models agree. Compared to free space optical lattices,
quantum uncertainties of the potential and the possibility of atom-field
entanglement lead to modified phase transition characteristics, the appearance
of new phases or even quantum superpositions of different phases. Using a
corresponding effective master equation, which can be numerically solved for
few particles, we can study time evolution including dissipation. As an example
we exhibit the microscopic processes behind the transition dynamics from a Mott
insulator like state to a self-ordered superradiant state of the atoms, which
appears as steady state for transverse atomic pumping.


title: The dynamical rigid body with memory

abstract:
  In the present paper we describe the dynamics of the revised rigid body, the
dynamics of the rigid body with distributed delays and the dynamics of the
fractional rigid body. We analyze the stationary states for given values of the
rigid body's parameters.


title: Action of Hecke operators on Siegel theta series II

abstract:
  Given a Siegel theta series and a prime p not dividing the level of the theta
series, we apply to the theta series the n+1 Hecke operators that generate the
local Hecke algebra at p. We show that the average theta series is an eigenform
and we compute the eigenvalues.


title: Time Scaling of Chaotic Systems: Application to Secure Communications

abstract:
  The paper deals with time-scaling transformations of dynamical systems. Such
scaling functions operate a change of coordinates on the time axis of the
system trajectories preserving its phase portrait. Exploiting this property, a
chaos encryption technique to transmit a binary signal through an analog
channel is proposed. The scheme is based on a suitable time-scaling function
which plays the role of a private key. The encoded transmitted signal is proved
to resist known decryption attacks offering a secure and reliable
communication.


title: Hecke operators on Hilbert-Siegel modular forms

abstract:
  We define Hilbert-Siegel modular forms and Hecke "operators" acting on them.
As with Hilbert modular forms, these linear transformations are not linear
operators until we consider a direct product of spaces of modular forms (with
varying groups), modulo natural identifications we can make between certain
spaces. With Hilbert-Siegel forms we identify several families of natural
identifications between certain spaces of modular forms. We associate the
Fourier coefficients of a form in our product space to even integral lattices,
independent of a basis and choice of coefficient rings. We then determine the
action of the Hecke operators on these Fourier coefficients, paralleling the
result of Hafner and Walling for Siegel modular forms (where the number field
is the field of rationals).


title: Exploring the chiral regime with dynamical overlap fermions

abstract:
  I report the status of the dynamical overlap fermion project by the JLQCD and
TWQCD collaborations. So far, the simulations have been completed with two
flavors of overlap sea quarks in a wide range of sea quark mass corresponding
the $p$-regime and the $\epsilon$-regime on a $16^3\times 32$ lattice at
$a=$0.12 fm. More recently, runs with 2+1 flavors of sea quarks have also
started. This talk mainly discusses the physics results on the $N_f=2$ lattice
after describing the lattice formulation and algorithms.


title: NGC3147: a "true" Seyfert 2 without the broad-line region

abstract:
  We report on simultaneous optical and X-ray observations of the Seyfert
galaxy, NGC3147. The XMM-Newton spectrum shows that the source is unabsorbed in
the X-rays ($N_H<5\times10^{20}$ cm$^{-2}$). On the other hand, no broad lines
are present in the optical spectrum. The origin of this optical/X-rays
misclassification (with respect to the Unification Model) cannot be attributed
to variability, since the observations in the two bands are simultaneous.
Moreover, a Compton-thick nature of the object can be rejected on the basis of
the low equivalent width of the iron K$\alpha$ line ($\simeq130$ eV) and the
large ratio between the 2-10 keV and the [OIII] fluxes. It seems therefore
inescapable to conclude that NGC3147 intrinsically lacks the Broad Line Region
(BLR), making it the first "true" Seyfert 2.


title: New developments in PHOKHARA Monte Carlo generator

abstract:
  The present status of the physics program, which led to the development of
the Monte Carlo event generator PHOKHARA is described. The possibility of using
the radiative return method in various aspects of hadronic physics, from the
measurement of the hadronic cross section, to detailed investigations of the
hadronic dynamics is emphasized. New results are presented showing how to
measure baryon form factors using the knowledge of their spin in
baryon-antibaryon production with subsequent decay.


title:
Retrospective Markov chain Monte Carlo methods for Dirichlet process
  hierarchical model

abstract:
  Inference for Dirichlet process hierarchical models is typically performed
using Markov chain Monte Carlo methods, which can be roughly categorised into
marginal and conditional methods. The former integrate out analytically the
infinite-dimensional component of the hierarchical model and sample from the
marginal distribution of the remaining variables using the Gibbs sampler.
Conditional methods impute the Dirichlet process and update it as a component
of the Gibbs sampler. Since this requires imputation of an infinite-dimensional
process, implementation of the conditional method has relied on finite
approximations. In this paper we show how to avoid such approximations by
designing two novel Markov chain Monte Carlo algorithms which sample from the
exact posterior distribution of quantities of interest. The approximations are
avoided by the new technique of retrospective sampling. We also show how the
algorithms can obtain samples from functionals of the Dirichlet process. The
marginal and the conditional methods are compared and a careful simulation
study is included, which involves a non-conjugate model, different datasets and
prior specifications.


title: Robust non-adiabatic molecular dynamics for metals and insulators

abstract:
  We present a new formulation of the correlated electron-ion dynamics (CEID)
scheme, which systematically improves Ehrenfest dynamics by including quantum
fluctuations around the mean-field atomic trajectories. We show that the method
can simulate models of non-adiabatic electronic transitions, and test it
against exact integration of the time-dependent Schroedinger equation. Unlike
previous formulations of CEID, the accuracy of this scheme depends on a single
tunable parameter which sets the level of atomic fluctuations included. The
convergence to the exact dynamics by increasing the tunable parameter is
demonstrated for a model two level system. This algorithm provides a smooth
description of the non-adiabatic electronic transitions which satisfies the
kinematic constraints (energy and momentum conservation) and preserves quantum
coherence. The applicability of this algorithm to more complex atomic systems
is discussed.


title: Trees, linear orders and G\^ateaux smooth norms

abstract:
  We introduce a linearly ordered set Z and use it to prove a necessity
condition for the existence of a G\^ateaux smooth norm on C(T), where T is a
tree. This criterion is directly analogous to the corresponding equivalent
condition for Fr\'echet smooth norms. In addition, we prove that if C(T) admits
a G\^ateaux smooth lattice norm then it also admits a lattice norm with
strictly convex dual norm.


title: Analyzing covert social network foundation behind terrorism disaster

abstract:
  This paper addresses a method to analyze the covert social network foundation
hidden behind the terrorism disaster. It is to solve a node discovery problem,
which means to discover a node, which functions relevantly in a social network,
but escaped from monitoring on the presence and mutual relationship of nodes.
The method aims at integrating the expert investigator's prior understanding,
insight on the terrorists' social network nature derived from the complex graph
theory, and computational data processing. The social network responsible for
the 9/11 attack in 2001 is used to execute simulation experiment to evaluate
the performance of the method.


title: Path Integral Representations on the Complex Sphere

abstract:
  In this paper we discuss the path integral representations for the coordinate
systems on the complex sphere S3C. The Schroedinger equation, respectively the
path integral, separates in exactly 21 orthogonal coordinate systems. We
enumerate these coordinate systems and we are able to present the path integral
representations explicitly in the majority of the cases. In each solution the
expansion into the wave-functions is stated. Also, the kernel and the
corresponding Green function can be stated in closed form in terms of the
invariant distance on the sphere, respectively on the hyperboloid.


title: Hamiltonian stationary Lagrangian tori contained in a hypersphere

abstract:
  The Clifford torus is a torus in a three-dimensional sphere. Homogeneous tori
are simple generalization of the Clifford torus which still in a
three-dimensional sphere. There is a way to construct tori in a
three-dimensional sphere using the Hopf fibration. In this paper, all
Hamiltonian stationary Lagrangian tori which is contained in a hypersphere in
the complex Euclidean plane are constructed explicitly. Then it is shown that
they are homogeneous tori. For the construction, flat quaternionic connections
of Hamiltonian stationary Lagrangian tori are considered and a spectral curve
of an associated family of them is used.


title: Stability of the Gibbs Sampler for Bayesian Hierarchical Models

abstract:
  We characterise the convergence of the Gibbs sampler which samples from the
joint posterior distribution of parameters and missing data in hierarchical
linear models with arbitrary symmetric error distributions. We show that the
convergence can be uniform, geometric or sub-geometric depending on the
relative tail behaviour of the error distributions, and on the parametrisation
chosen. Our theory is applied to characterise the convergence of the Gibbs
sampler on latent Gaussian process models. We indicate how the theoretical
framework we introduce will be useful in analyzing more complex models.


title:
Top-Down Causation by Information Control: From a Philosophical Problem
  to a Scientific Research Program

abstract:
  It has been claimed that different types of causes must be considered in
biological systems, including top-down as well as same-level and bottom-up
causation, thus enabling the top levels to be causally efficacious in their own
right. To clarify this issue, important distinctions between information and
signs are introduced here and the concepts of information control and
functional equivalence classes in those systems are rigorously defined and used
to characterise when top down causation by feedback control happens, in a way
that is testable. The causally significant elements we consider are equivalence
classes of lower level processes, realised in biological systems through
different operations having the same outcome within the context of information
control and networks.


title:
NNNLO correction to the toponium and bottomonium wave-functions at the
  origin

abstract:
  We report new results of the NNNLO correction to the S-wave quarkonium
wave-functions at the origin, which also provide an estimate of the resonance
cross section in t-tbar threshold production at the ILC.


title:
Free energy of static quarks and the renormalized Polyakov loop in full
  QCD

abstract:
  We present results from a detailed study of singlet free energies in full QCD
with realistic quark masses. An improved scheme for the non-perturbative
renormalization of the Polyakov loop is used and we compare its temperature
dependence for QCD with different flavor content. We also analyze screening
masses extracted from singlet free energies at various temperatures close to
and above the QCD transition temperature. We conclude that the temperature
dependence of screening masses is well described by perturbation theory up to a
non-perturbative pre-factor. An effective running coupling has been determined
for all temperature values giving additional insight into screening phenomena
at high temperature.


title:
Multi-line (sub)millimetre observations of the high-mass proto cluster
  IRAS 05358+3543

abstract:
  Since most high- and intermediate-mass protostars are at great distance and
form in clusters, high linear resolution observations are needed to investigate
their physical properties. To study the gas in the innermost region around the
protostars in the proto-cluster IRAS 05358+3543, we observed the source in
several transitions of methanol and other molecular species with the Plateau de
Bure Interferometer and the Submillimeter Array, reaching a linear resolution
of 1100 AU. We determine the kinetic temperature of the gas around the
protostars through an LVG and LTE analysis of their molecular emission; the
column densities of CH3OH, CH3CN and SO2 are also derived. Constrains on the
density of the gas are estimated for two of the protostellar cores. We find
that the dust condensations are in various evolutionary stages. The powerhouse
of the cluster, mm1a, harbours a hot core with T~220 (75<T<330) K. A
double-peaked profile is detected in several transitions toward mm1a, and we
found a velocity gradient along a linear structure which could be perpendicular
to one of the outflows from the vicinity of mm1a. Since the size of the
double-peaked emission is less than 1100 AU, we suggest that mm1a might host a
massive circumstellar disk. The other sources are in earlier stages of star
formation. The least active source, mm3, could be a starless massive core,
since it is cold (T<20 K), with a large reservoir of accreting material (M ~ 19
M_\odot), but no molecular emission peaks on it.


title: Unparticle Physics in Single Top Signals

abstract:
  We study the single production of top quarks in $e^+e^-, ep$ and $pp$
collisions in the context of unparticle physics through the Flavor Violating
(FV) unparticle vertices and compute the total cross sections for single top
production as functions of scale dimension $d_{\U}$. We find that among all,
LHC is the most promising facility to probe the unparticle physics via single
top quark production processes.


title: Universality and massive excitations in 3d 3-state Potts model

abstract:
  The mass spectrum of the 3d 3-state Potts model is considered in the broken
phase (a) near the second order Ising critical point in the
temperature-magnetic field plane and (b) near the weakly first order transition
point at zero magnetic field. In the case (a), the mass spectrum is compared
with the prediction from universality of mass ratios in the 3d Ising class; in
the case (b) a mass ratio is determined to be compared with the corresponding
one in the spectrum of screening masses of the (3+1)d SU(3) pure gauge theory
at finite temperature in the deconfined phase near the transition.


title:
BCS-BEC crossover of neutron pairs in symmetric and asymmetric nuclear
  matter

abstract:
  We propose new types of density dependent contact pairing interaction which
reproduce the pairing gaps in symmetric and neutron matter obtained by a
microscopic treatment based on the nucleon-nucleon interaction. These
interactions are able to simulate the pairing gaps of either the bare
interaction or the interaction screened by the medium polarization effects. It
is shown that the medium polarization effects cannot be cast into the density
power law function usually introduced together with the contact interaction and
require the introduction of another isoscalar term. The BCS-BEC crossover of
neutrons pairs in symmetric and symmetric nuclear matter is studied by using
these contact interactions. It is shown that the bare and screened pairing
interactions lead to different features of the BCS-BEC crossover in symmetric
nuclear matter. For the screened pairing interaction, a two-neutron BEC state
is formed in symmetric matter at $k_{Fn}\sim 0.2$ fm$^{-1}$ (neutron density
$\rho_n/\rho_0\sim 10^{-3}$). Contrary the bare interaction does not form the
BEC state at any neutron density.


title: Adaptive Importance Sampling in General Mixture Classes

abstract:
  In this paper, we propose an adaptive algorithm that iteratively updates both
the weights and component parameters of a mixture importance sampling density
so as to optimise the importance sampling performances, as measured by an
entropy criterion. The method is shown to be applicable to a wide class of
importance sampling densities, which includes in particular mixtures of
multivariate Student t distributions. The performances of the proposed scheme
are studied on both artificial and real examples, highlighting in particular
the benefit of a novel Rao-Blackwellisation device which can be easily
incorporated in the updating scheme.


title: Heun and Mathieu functions as solutions of the Dirac equation

abstract:
  We give examples of where the Heun function exists as solutions of wave
equations encountered in general relativity. While the Dirac equation written
in the background of Nutku helicoid metric yields Mathieu functions as its
solutions in four spacetime dimensions, the trivial generalization to five
dimensions results in the double confluent Heun function. We reduce this
solution to the Mathieu function with some transformations. We must apply
Atiyah-Patodi-Singer spectral boundary conditions to this system since the
metric has a singularity at the origin.


title: Near-Field Radio Holography of Large Reflector Antennas

abstract:
  We summarise the mathematical foundation of the holographic method of
measuring the reflector profile of an antenna or radio telescope. In
particular, we treat the case, where the signal source is located at a finite
distance from the antenna under test, necessitating the inclusion of the
so-called Fresnel field terms in the radiation integrals. We assume a ``full
phase'' system with reference receiver to provide the reference phase. We
describe in some detail the hardware and software implementation of the system
used for the holographic measurement of the 12m ALMA prototype submillimeter
antennas. We include a description of the practicalities of a measurement and
surface setting. The results for both the VertexRSI and AEC
(Alcatel-EIE-Consortium) prototype ALMA antennas are presented.


title: Particle Filters for Partially Observed Diffusions

abstract:
  In this paper we introduce a novel particle filter scheme for a class of
partially-observed multivariate diffusions. %continuous-time dynamic models
where the %signal is given by a multivariate diffusion process. We consider a
variety of observation schemes, including diffusion observed with error,
observation of a subset of the components of the multivariate diffusion and
arrival times of a Poisson process whose intensity is a known function of the
diffusion (Cox process). Unlike currently available methods, our particle
filters do not require approximations of the transition and/or the observation
density using time-discretisations. Instead, they build on recent methodology
for the exact simulation of the diffusion process and the unbiased estimation
of the transition density as described in \cite{besk:papa:robe:fear:2006}. %In
particular, w We introduce the Generalised Poisson Estimator, which generalises
the Poisson Estimator of \cite{besk:papa:robe:fear:2006}. %Thus, our filters
avoid the systematic biases caused by %time-discretisations and they have
significant computational %advantages over alternative continuous-time filters.
These %advantages are supported theoretically by a A central limit theorem is
given for our particle filter scheme.


title:
Critical properties of the four-state Commutative Random Permutation
  Glassy Potts model in three and four dimensions

abstract:
  We investigate the critical properties of the four-state commutative random
permutation glassy Potts model in three and four dimensions by means of Monte
Carlo simulation and of a finite size scaling analysis. Thanks to the use of a
field programmable gate array we have been able to thermalize a large number of
samples of systems with large volume. This has allowed us to observe a
spin-glass ordered phase in d=4 and to study the critical properties of the
transition. In d=3, our results are consistent with the presence of a
Kosterlitz-Thouless transition, but we cannot exclude transient effects due to
a value of the lower critical dimension slightly below 3.


title: Chiral dynamics of few-nucleon systems

abstract:
  I discuss some recent developments in chiral effective field theory for
few-nucleon systems.


title: INTEGRAL - operating high-energy detectors for five years in space

abstract:
  The INTEGRAL satellite, which studies the Universe in the hard X-ray and soft
Gamma-ray domain, has been operational for 5 years now. The X-ray telescopes,
which use the coded mask technique, provide unprecedented spectral and imaging
resolution. This led to a number of discoveries, such as the distribution of
diffuse emission in the Galaxy, the discovery of highly absorbed sources and
fast X-ray transients in the Galactic Plane, localization of ~50 Gamma-ray
bursts, and the resolution of the cosmic X-ray background around its peak at 30
keV. About 300 previously known X-ray sources have been detected and in
addition more than 200 new sources have been discovered. INTEGRAL provides
spectra starting at 3 keV and ranging up to several hundred keV. This article
gives a brief overview about the major discoveries of INTEGRAL.


title: Complex Kerr Geometry, Twistors and the Dirac Electron

abstract:
  The Kerr-Newman spinning particle displays some remarkable relations to the
Dirac electron and has a reach spinor structure which is based on a twistorial
description of the Kerr congruence determined by the Kerr theorem. We consider
the relation between this spinor-twistorial structure and spinors of the Dirac
equation, and show that the Dirac equation may naturally be incorporated into
Kerr-Schild formalism as a master equation controlling the twistorial structure
of Kerr geometry. As a result, the Dirac electron acquires an extended
space-time structure having clear coordinate description with natural
incorporation of a gravitational field. The relation between the Dirac wave
function and Kerr geometry is realized via a chain of links: {\it Dirac wave
function $ \Rightarrow $ Complex Kerr-Newman Source $ \Rightarrow $ Kerr
Theorem $ \Rightarrow $ Real Kerr geometry.} As a result, the wave function
acquires the role of an ``order parameter'' which controls spin, dynamics, and
twistorial polarization of Kerr-Newman space-time.


title: Four-nucleon force using the method of unitary transformation

abstract:
  We discuss in detail the derivation of the leading four-nucleon force in
chiral effective field theory using the method of unitary transformation. The
resulting four-nucleon force is given in both momentum and configuration space.
It does not contain any unknown parameters and can be used in few- and
many-nucleon studies.


title:
Group Analysis of Variable Coefficient Diffusion-Convection Equations.
  IV. Potential Symmetries

abstract:
  This paper completes investigation of symmetry properties of nonlinear
variable coefficient diffusion-convection equations of the form
$f(x)u_t=(g(x)A(u)u_x)_x+h(x)B(u)u_x$. Potential symmetries of equations from
the considered class are found and the connection of them with Lie symmetries
of diffusion-type equations is shown. Exact solutions of the Fujita--Storm
equation $u_t=(u^{-2}u_x)_x$ are constructed.


title: Scattering of Long-Wavelength Gravitational Waves

abstract:
  We consider the scattering of a low-frequency gravitational wave by a massive
compact body in vacuum. We apply partial-wave methods to compute amplitudes for
the helicity-conserving and helicity-reversing contributions to the cross
section, accurate to first order in $M\omega$. Contrary to previous claims, we
find that the partial-wave cross section agrees with the cross section derived
via perturbation-theory methods.


title: There are non homotopic framed homotopies of long knots

abstract:
  Let $\mathcal {M}$ be the space of all, including singular, long knots in
3-space and for which a fixed projection into the plane is an immersion. Let
$cl(\Sigma^{(1)}_{iness})$ be the closure of the union of all singular knots in
$\mathcal {M}$ with exactly one ordinary double point and such that the two
resolutions represent the same (non singular) knot type. We call
$\Sigma^{(1)}_{iness}$ the {\em inessential walls} and we call $\mathcal
{M}_{ess} = \mathcal {M} \setminus cl(\Sigma^{(1)}_{iness})$ the {\em essential
diagram space}. We construct a non trivial class in $H^1(\mathcal {M}_{ess};
\mathbb{Z}[A, A^{-1}])$ by an extension of the Kauffman bracket. This implies
in particular that there are loops in $\mathcal {M}_{ess}$ which consist of
regular isotopies of knots together with crossing changings and which are not
contractible in $\mathcal {M}_{ess}$ (leading to the title of the paper).
  We conjecture that our construction gives rise to a new knot polynomial for
knots of unknotting number one.


title: Study of the Dynamics of Large Reflector Antennas with Accelerometers

abstract:
  The Atacama Large Millimeter Array (ALMA) will consist of up to 64
state-of-the-art sub-mm telescopes, subject to stringent performance
specifications which will push the boundaries of the technology, and makes
testing of antenna performance a likewise challenging task. Two antenna
prototypes were evaluated at the ALMA Test Facility at the Very Large Array
site in New Mexico, USA. The dynamic behaviour of the antennas under
operational conditions was investigated with the help of an accelerometer
system capable of measuring rigid body motion of the elevation structure of the
antenna, as well as a few low-order deformation modes, resulting in dynamic
performance numbers for pointing stability, reflector surface stability, path
length stability, and structure flexure. Special emphasis was given to wind
effects, one of the major factors affecting performance on timescales of
seconds to tens of minutes. This paper describes the accelerometer system, its
capabilities and limitations, and presents the dynamic performance results of
the two prototype antennas investigated.


title: Analysis of a Mixed Strategy for Multiple Relay Networks

abstract:
  In their landmark paper Cover and El Gamal proposed different coding
strategies for the relay channel with a single relay supporting a communication
pair. These strategies are the decode-and-forward and compress-and-forward
approach, as well as a general lower bound on the capacity of a relay network
which relies on the mixed application of the previous two strategies. So far,
only parts of their work - the decode-and-forward and the compress-and-forward
strategy - have been applied to networks with multiple relays.
  This paper derives a mixed strategy for multiple relay networks using a
combined approach of partial decode-and-forward with N +1 levels and the ideas
of successive refinement with different side information at the receivers.
After describing the protocol structure, we present the achievable rates for
the discrete memoryless relay channel as well as Gaussian multiple relay
networks. Using these results we compare the mixed strategy with some special
cases, e. g., multilevel decode-and-forward, distributed compress-and-forward
and a mixed approach where one relay node operates in decode-and-forward and
the other in compress-and-forward mode.


title: (1+1)-dimensional separation of variables

abstract:
  In this paper we explore general conditions which guarantee that the geodesic
flow on a 2-dimensional manifold with indefinite signature is locally
separable. This is equivalent to showing that a 2-dimensional natural
Hamiltonian system on the hyperbolic plane possesses a second integral of
motion which is a quadratic polynomial in the momenta associated with a
2nd-rank Killing tensor. We examine the possibility that the integral is
preserved by the Hamiltonian flow on a given energy hypersurface only (weak
integrability) and derive the additional requirement necessary to have
conservation at arbitrary values of the Hamiltonian (strong integrability).
Using null coordinates, we show that the leading-order coefficients of the
invariant are arbitrary functions of one variable in the case of weak
integrability. These functions are quadratic polynomials in the coordinates in
the case of strong integrability. We show that for $(1+1)$-dimensional systems
there are three possible types of conformal Killing tensors, and therefore,
three distinct separability structures in contrast to the single standard
Hamilton-Jacobi type separation in the positive definite case. One of the new
separability structures is the complex/harmonic type which is characterized by
complex separation variables. The other new type is the linear/null separation
which occurs when the conformal Killing tensor has a null eigenvector.


title:
Pairing mean-field theory for the dynamics of dissociation of molecular
  Bose-Einstein condensates

abstract:
  We develop a pairing mean-field theory to describe the quantum dynamics of
the dissociation of molecular Bose-Einstein condensates into their constituent
bosonic or fermionic atoms. We apply the theory to one, two, and
three-dimensional geometries and analyze the role of dimensionality on the atom
production rate as a function of the dissociation energy. As well as
determining the populations and coherences of the atoms, we calculate the
correlations that exist between atoms of opposite momenta, including the column
density correlations in 3D systems. We compare the results with those of the
undepleted molecular field approximation and argue that the latter is most
reliable in fermionic systems and in lower dimensions. In the bosonic case we
compare the pairing mean-field results with exact calculations using the
positive-$P$ stochastic method and estimate the range of validity of the
pairing mean-field theory. Comparisons with similar first-principle simulations
in the fermionic case are currently not available, however, we argue that the
range of validity of the present approach should be broader for fermions than
for bosons in the regime where Pauli blocking prevents complete depletion of
the molecular condensate.


abstract:
  The Double Chooz reactor neutrino experiment will be the next detector to
search for a non vanishing theta13 mixing angle with unprecedented sensitivity,
which might open the way to unveiling CP violation in the leptonic sector. The
measurement of this angle will be based in a precise comparison of the
antineutrino spectrum at two identical detectors located at different distances
from the Chooz nuclear reactor cores in France. Double Chooz is particularly
attractive because of its capability to measure sin2(2theta13) to 3 sigmas if
sin2(2theta13) > 0.05 or to exclude sin2(2theta13) down to 0.03 at 90% C.L. for
Dm2 = 2.5 x 10-3 eV2 in three years of data taking with both detectors. The
construction of the far detector starts in 2008 and the first neutrino results
are expected in 2009. The current status of the experiment, its physics
potential and design and expected performance of the detector are reviewed.


title: Ergodicity of Langevin Processes with Degenerate Diffusion in Momentums

abstract:
  This paper introduces a geometric method for proving ergodicity of degenerate
noise driven stochastic processes. The driving noise is assumed to be an
arbitrary Levy process with non-degenerate diffusion component (but that may be
applied to a single degree of freedom of the system). The geometric conditions
are the approximate controllability of the process the fact that there exists a
point in the phase space where the interior of the image of a point via a
secondarily randomized version of the driving noise is non void. The paper
applies the method to prove ergodicity of a sliding disk governed by
Langevin-type equations (a simple stochastic rigid body system). The paper
shows that a key feature of this Langevin process is that even though the
diffusion and drift matrices associated to the momentums are degenerate, the
system is still at uniform temperature.


title: Carter's constant revealed

abstract:
  A new formulation of Carter's constant for geodesic motion in Kerr black
holes is given. It is shown that Carter's constant corresponds to the total
angular momentum plus a precisely defined part which is quadratic in the linear
momenta. The characterization is exact in the weak field limit obtained by
letting the gravitational constant go to zero. It is suggested that the new
form can be useful in current studies of the dynamics of extreme mass ratio
inspiral (EMRI) systems emitting gravitational radiation.


title:
Survivable MPLS Over Optical Transport Networks: Cost and Resource Usage
  Analysis

abstract:
  In this paper we study different options for the survivability implementation
in MPLS over Optical Transport Networks (OTN) in terms of network resource
usage and configuration cost. We investigate two approaches to the
survivability deployment: single layer and multilayer survivability and present
various methods for spare capacity allocation (SCA) to reroute disrupted
traffic. The comparative analysis shows the influence of the offered traffic
granularity and the physical network structure on the survivability cost: for
high bandwidth LSPs, close to the optical channel capacity, the multilayer
survivability outperforms the single layer one, whereas for low bandwidth LSPs
the single layer survivability is more cost-efficient. On the other hand,
sparse networks of low connectivity parameter use more wavelengths for optical
path routing and increase the configuration cost, as compared with dense
networks. We demonstrate that by mapping efficiently the spare capacity of the
MPLS layer onto the resources of the optical layer one can achieve up to 22%
savings in the total configuration cost and up to 37% in the optical layer
cost. Further savings (up to 9 %) in the wavelength use can be obtained with
the integrated approach to network configuration over the sequential one,
however, at the increase in the optimization problem complexity. These results
are based on a cost model with different cost variations, and were obtained for
networks targeted to a nationwide coverage.


title:
Crowded-Field Astrometry with the Space Interferometry Mission - I.
  Estimating the Single-Measurement Astrometric Bias Arising from Confusion

abstract:
  The accuracy of position measurements on stellar targets with the future
Space Interferometry Mission (SIM) will be limited not only by photon noise and
by the properties of the instrument (design, stability, etc.) and the overall
measurement program (observing strategy, reduction methods, etc.), but also by
the presence of other "confusing" stars in the field of view (FOV). We use a
simple "phasor" model as an aid to understanding the main effects of this
"confusion bias" in single observations with SIM. This analytic model has been
implemented numerically in a computer code and applied to a selection of
typical SIM target fields drawn from some of the Key Projects already accepted
for the Mission. We expect that less than 1% of all SIM targets will be
vulnerable to confusion bias; we show that for the present SIM design,
confusion may be a concern if the surface density of field stars exceeds 0.4
star/arcsec^2. We have developed a software tool as an aid to ascertaining the
possible presence of confusion bias in single observations of any arbitrary
field. Some a priori knowledge of the locations and spectral energy
distributions of the few brightest stars in the FOV is helpful in establishing
the possible presence of confusion bias, but the information is in general not
likely to be available with sufficient accuracy to permit its removal. We
discuss several ways of reducing the likelihood of confusion bias in crowded
fields. Finally, several limitations of the present semi-analytic approach are
reviewed, and their effects on the present results are estimated. The simple
model presented here provides a good physical understanding of how confusion
arises in a single SIM observation, and has sufficient precision to establish
the likelihood of a bias in most cases.


title:
Silicon in the Quantum Limit: Quantum Computing and Decoherence in
  Silicon Architectures

abstract:
  Semiconductor architectures hold promise for quantum information processing
(QIP) applications due to their large industrial base and perceived scalability
potential. Electron spins in silicon in particular may be an excellent
architecture for QIP and also for spin electronics (spintronics) applications.
While the charge of an electron is easily manipulated by charged gates, the
spin degree of freedom is well isolated from charge fluctuations. Inherently
small spin-orbit coupling and the existence of a spin-zero Si isotope
facilitate long single spin qubit coherence times. Here we consider the
relaxation properties of localized electronic states in silicon due to donors,
quantum wells, and quantum dots, including effects due to phonons and Rashba
spin-orbit coupling. Our analysis is impeded by the complicated, many-valley
band structure of silicon and previously unaddressed physics in silicon quantum
wells. We find that electron spins in silicon and especially strained silicon
have excellent decoherence properties. Where possible we compare with
experiment to test our theories. We go beyond issues of coherence in a quantum
computer to problems of control and measurement. Precisely what makes spin
relaxation so long in semiconductor architectures makes spin measurement so
difficult. To address this, we propose a new scheme for spin readout which has
the added benefit of automatic spin initialization, a vital component of
quantum computing and quantum error correction. Our results represent important
practical milestones on the way to the design and construction of a
silicon-based quantum computer.


title:
Diophantine approximation, Khintchine's theorem, torus geometry and
  Hausdorff dimension

abstract:
  A general form of the Borel-Cantelli Lemma and its connection with the proof
of Khintchine's Theorem on Diophantine approximation and the more general
Khintchine-Groshev theorem are discussed. The torus geometry in the planar case
allows a relatively direct proof of the planar Groshev theorem for the set of
$\psi$-approximable points in the plane. The construction and use of Haudsorff
measure and dimension are explained and the notion of ubiquity, which is
effective in estimating the lower bound of the Hausdorff dimension for quite
general lim sup sets, is described. An application is made to obtain the
Hausdorff dimension of the set of approximable points in the plane when
$\psi(q)=q^{-v}$, $v>0$, corresponding to the planar Jarnik-Besicovich theorem.


title: Searches for Higgs and BSM at the Tevatron

abstract:
  This paper presents an overview of recent experimental direct searches for
Higgs-boson and beyond-the-standard-model (BSM) physics shown in the plenary
session at the SUSY07 conference. The results reported correspond to an
integrated luminosity of up to 2 fb-1 of Run II data from $p\bar{p}$ collisions
collected by the CDF and D0 experiments at the Fermilab Tevatron Collider.
Searches covered include: the standard model (SM) Higgs boson (including
sensitivity projections), the minimal supersymmetric extension of the standard
model (MSSM), charged Higgs bosons and extended Higgs models, supersymmetric
decays that conserve R-parity, gauge-mediated supersymmetric breaking models,
long-lived particles, leptoquarks, extra gauge bosons, extra dimensions, and
finally signature-based searches. Given the excellent performance of the
collider and the continued productivity of the experiments, the Tevatron
physics potential looks very promising for discovery in the coming larger data
sets. In particular, the Higgs boson could be observed if its mass is light or
near 160 GeV.


title:
Expansions for the Bollobas-Riordan polynomial of separable ribbon
  graphs

abstract:
  We define 2-decompositions of ribbon graphs, which generalise 2-sums and
tensor products of graphs. We give formulae for the Bollobas-Riordan polynomial
of such a 2-decomposition, and derive the classical Brylawski formula for the
Tutte polynomial of a tensor product as a (very) special case. This study was
initially motivated from knot theory, and we include an application of our
formulae to mutation in knot diagrams.


title: Topics on String Phenomenology

abstract:
  These lectures present some topics of string phenomenology and contain two
parts. In the first part, I review the possibility of lowering the string scale
in the TeV region, that provides a theoretical framework for solving the mass
hierarchy problem and unifying all interactions. The apparent weakness of
gravity can then be accounted by the existence of large internal dimensions, in
the submillimeter region, and transverse to a braneworld where our universe
must be confined. I review the main properties of this scenario and its
implications for observations at both particle colliders, and in
non-accelerator gravity experiments. In the second part, I discuss a simple
framework of toroidal string models with magnetized branes, that offers an
interesting self-consistent setup for string phenomenology. I will present an
algorithm for fixing the geometric parameters of the compactification, build
calculable particle physics models such as a supersymmetric SU(5) Grand Unified
Theory with three generations of quarks and leptons, and implement low energy
supersymmetry breaking with gauge mediation that can be studied directly at the
string level.


title: Finite Field Experiments (with an Appendix by Stefan Wiedmann)

abstract:
  We explain how to use computer experiments over finite fields to gain
heuristic information about the solution set of polynomial equations in
characteristic zero. These are notes of a tutorial I gave at the NATO Advanced
Study Institute on Higher-Dimensional Geometry over Finite Fields in G"ottingen
2007.


title:
Shape, size and robustness: feasible regions in the parameter space of
  biochemical networks

abstract:
  The concept of robustness of regulatory networks has been closely related to
the nature of the interactions among genes, and the capability of pattern
maintenance or reproducibility. Defining this robustness property is a
challenging task, but mathematical models have often associated it to the
volume of the space of admissible parameters. Not only the volume of the space
but also its topology and geometry contain information on essential aspects of
the network, including feasible pathways, switching between two parallel
pathways or distinct/disconnected active regions of parameters. A general
method is presented here to characterize the space of admissible parameters, by
writing it as a semi-algebraic set, and then theoretically analyzing its
topology and geometry, as well as volume. This method provides a more objective
and complete measure of the robustness of a developmental module. As an
illustration, the segment polarity gene network is analyzed.


title: Spin-c Prequantization and Symplectic Cutting

abstract:
  We define spin-c prequantization of a symplectic manifold to be a spin-c
structure and a connection which are compatible with the symplectic form. We
describe the cutting of an S^1-equivariant spin-c prequantization. The cutting
process involves a choice of a spin-c prequantization for the complex plane. We
prove that the cutting is possible if and only if the moment map level set
along which the cutting is done is compatible with this choice.


title: Asymptotics of the quantum Hamming bound for subsystem codes

abstract:
  Ashikhmin and Litsyn showed that all binary stabilizer codes - pure or impure
- of sufficiently large length obey the quantum Hamming bound, ruling out the
possibility that impure codes of large length can outperform pure codes with
respect to sphere packing. In contrast we show that impure subsystem codes do
not obey the quantum Hamming bound for pure subsystem codes, not even
asymptotically. We show that there exist arbitrarily long Bacon-Shor codes that
violate the quantum Hamming bound.


title: An approximation trichotomy for Boolean #CSP

abstract:
  We give a trichotomy theorem for the complexity of approximately counting the
number of satisfying assignments of a Boolean CSP instance. Such problems are
parameterised by a constraint language specifying the relations that may be
used in constraints. If every relation in the constraint language is affine
then the number of satisfying assignments can be exactly counted in polynomial
time. Otherwise, if every relation in the constraint language is in the
co-clone IM_2 from Post's lattice, then the problem of counting satisfying
assignments is complete with respect to approximation-preserving reductions in
the complexity class #RH\Pi_1. This means that the problem of approximately
counting satisfying assignments of such a CSP instance is equivalent in
complexity to several other known counting problems, including the problem of
approximately counting the number of independent sets in a bipartite graph. For
every other fixed constraint language, the problem is complete for #P with
respect to approximation-preserving reductions, meaning that there is no fully
polynomial randomised approximation scheme for counting satisfying assignments
unless NP=RP.


title:
Supergravity and Two-Field Inflation Effects in Right-Handed
  Sneutrino-Modified D-term Inflation

abstract:
  We extend previous work on the minimal D-term inflation model modified by
Right-Handed (RH) sneutrino fields to include additional inflaton-sector SUGRA
corrections and two-field inflation effects. We show that SUGRA corrections
simultaneously allow n_{s} to be within 3-year WMAP limits and the cosmic
string contribution to the CMB power spectrum to be less than 5%. For gauge
coupling g < 1, the CMB contribution from cosmic strings is predicted to be at
least 1% while the spectral index is predicted to be less than 0.968 for a CMB
string contribution less than 5%. Treating the inflaton-RH sneutrino system as
a two-field inflation model, we show that the time-dependence of the RH
sneutrino field strongly modifies the single-field results for values of RH
sneutrino mass m_{\Phi} > 0.1 H. The running spectral index is \alpha = -0.0002
when m_{\Phi} < 0.1 H but increases to positive values as m_{\Phi}/H increases,
with \alpha > 0.008 for m_{\Phi} > 1.0 H.


title: Large-scale Propagation of Very Light Jets in Galaxy Clusters

abstract:
  We performed MHD simulations of very light bipolar jets with density
contrasts down to 10^-4 in axisymmetry, which were injected into a medium of
constant density and evolved up to 200 kpc (200 r_j) full length. These jets
show weak and roundish bow shocks as well as broad cocoons and thermalize their
kinetic energy very efficiently. We argue that very light jets are necessary to
match low-frequency radio observations of radio lobes as well as the bow shocks
seen in X-rays. Due to the slow propagation, the backflows and their turbulent
interaction in the midplane are important for a realistic global appearance.


title: Cosmological Unparticle Correlators

abstract:
  We introduce and study an extension of the correlator of unparticle matter
operators in a cosmological environment. Starting from FRW spaces we specialize
to a de Sitter spacetime and derive its inflationary power spectrum which we
find to be almost flat. We finally investigate some consequences of requiring
the existence of a unitary boundary conformal field theory in the framework of
the dS/CFT correspondence.


title: On the Euclidean Version of the Photon Number Integral

abstract:
  We reconsider the Euclidean version of the photon number integral introduced
in ref 1. This integral is well defined for any smooth non-self-intersecting
curve in $\R^N$. Besides studying general features of this integral (including
it s conformal invariance), we evaluate it explicitly for the ellipse. The
result is $n_{ellipse}=(\xi^{-1}+\xi)\pi^2$, where $\xi$ is the ratio of the
minor and major axes. This is in agreement with the previous result
$n_{circle}=2\pi^2$ and also with the conjecture that the minimum value of $n$
for any plane curve occurs for the circle.


title:
Inelastic Scattering and Spin Polarization in Dilute Magnetic
  Semiconductor (Ga,Mn)Sb

abstract:
  The Point Contact Andreev Reflection (PCAR) technique has already been used
to measure the spin polarization of some of the dilute magnetic semiconductors,
such as narrow-band (In,Mn)Sb, as well as wider gap (Ga,Mn)As. While in
(In,Mn)Sb conventional Andreev reflection has been demonstrated, in (Ga,Mn)As
quasiparticle density of states (DOS) broadening has been observed, possibly
due to inelastic scattering effects. Here, we investigate the spin
polarization, magnetic, and transport properties of epitaxially grown (Ga,Mn)Sb
films with the Curie temperature of ~ 10K. The spin polarization of 57+/-5% was
measured. Spectrum broadening in (Ga,Mn)Sb has also been observed.


title: Shape reconstruction from gradient data

abstract:
  We present a novel method for reconstructing the shape of an object from
measured gradient data. A certain class of optical sensors does not measure the
shape of an object, but its local slope. These sensors display several
advantages, including high information efficiency, sensitivity, and robustness.
For many applications, however, it is necessary to acquire the shape, which
must be calculated from the slopes by numerical integration. Existing
integration techniques show drawbacks that render them unusable in many cases.
Our method is based on approximation employing radial basis functions. It can
be applied to irregularly sampled, noisy, and incomplete data, and it
reconstructs surfaces both locally and globally with high accuracy.


title: The SuperNEMO double beta decay experiment

abstract:
  The SuperNEMO project studies the feasibility of employing a technique of
tracking plus calorimetry to search for neutrinoless double beta decay in 100
kg of enriched isotopes. It aims to reach an effective neutrino mass
sensitivity of 50 meV. The current status of the SuperNEMO R&D programme is
described, focusing on the main areas of improvement.


title:
Gamma Ray Bursts from the early Universe: predictions for present-day
  and future instruments

abstract:
  Long Gamma Ray Bursts (GRBs) constitute an important tool to study the
Universe near and beyond the epoch of reionization. We delineate here the
characteristics of an 'ideal' instrument for the search of GRBs at z>6-10. We
find that the detection of these objects requires soft band detectors with a
high sensitivity and moderately large FOV. In the light of these results, we
compare available and planned GRB missions, deriving conservative predictions
on the number of high-z GRBs detectable by these instruments along with the
maximum accessible redshift. We show that the Swift satellite will be able to
detect various GRBs at z>6, and likely at z>10 if the trigger threshold is
decreased by a factor of ~2. Furthermore, we find that INTEGRAL and GLAST are
not the best tool to detect bursts at z>6: the former being limited by the
small FOV, and the latter by its hard energy band and relatively low
sensitivity. Finally, future missions (SVOM, EDGE, but in particular EXIST)
will provide a good sample of GRBs at z>6 in a few years of operation.


title:
Tan(beta) enhanced Yukawa couplings for supersymmetric Higgs singlets at
  one loop

abstract:
  Extensions of the MSSM generically feature gauge singlet Higgs bosons. These
singlet Higgs bosons have tan(beta)-enhanced Yukawa couplings to down-type
quarks and leptons at the one-loop level. We present an effective Lagrangian
incorporating these Yukawa couplings and use it to study their effect on
singlet Higgs boson phenomenology within both the mnSSM and NMSSM. It is found
that the loop-induced couplings represent an appreciable effect for the singlet
pseudoscalar in particular, and may dominate its decay modes in some regions of
parameter space.


title: Broad Lyman-Alpha Emission from Supernova Remnants in Young Galaxies

abstract:
  Charge transfer (or exchange) reactions between hydrogen atoms and protons in
collisionless shocks of supernova remnants (SNRs) are a natural way of
producing broad Balmer, Lyman and other lines of hydrogen. We wish to quantify
the importance of shock-induced, non-thermal hydrogen emission from SNRs in
young galaxies. We present a method to estimate the luminosity of broad ($\sim
1000$ km s$^{-1}$) Ly$\alpha$, Ly$\beta$, Ly$\gamma$, H$\beta$ and P$\alpha$
lines, as well as the broad and narrow luminosities of the two-photon
(2$\gamma$) continuum, from existing measurements of the H$\alpha$ flux. The
expected broad Ly$\alpha$ luminosity per object is at most $\sim 10^{36}$ erg
s$^{-1}$. In principle, broad, ``non-radiative'' Ly$\alpha$ from SNRs in young
galaxies can be directly observed in the optical range of wavelengths. However,
by taking into consideration the different rates between core collapse and
thermonuclear supernovae, as well as the duration we expect to observe such
Ly$\alpha$ emission from SNRs, we expect their contribution to the total
Ly$\alpha$ luminosity from $z \sim 3$ to 5 galaxies to be negligibly small
($\sim 0.001 %$), compared to the radiative shock mechanism described by Shull
& Silk (1979). Though broad, non-thermal Ly$\alpha$ emission has never been
observed, these photons are produced in SNRs and hence the non-radiative
Ly$\alpha$ luminosity is a part of the intrinsic Ly$\alpha$ spectrum of young
galaxies.


title: Crossing the phantom divide in an interacting generalized Chaplygin gas

abstract:
  Unified generalized Chaplygin gas models assuming an interaction between dark
energy and dark matter fluids have been previously proposed. Following these
ideas, we consider a particular relation between dark densities, which allows
the possibility of a time varying equation of state for dark energy that
crosses the phantom divide at a recent epoch. Moreover, these densities decay
during all the evolution of the Universe, avoiding a Big Rip. We find also a
scaling solution, i.e. these densities are asymptotically proportional in the
future, which contributes to the solution of the coincidence problem.


title: Numerical obstructions to abelian surfaces in toric Fano 4-folds

abstract:
  Some of the 124 toric Fano 4-folds contain abelian surfaces but most do not:
in a few cases it is not known whether they do or not. By elementary methods,
with a little computer help, we exclude some more possibilities.


title:
Experimental validation and physical modelling of vocal folds
  pathologies

abstract:
  Voiced sounds involve self-sustained vocal folds oscillations due to the
interaction between the airflow and the vocal folds. Common vocal folds
pathologies like polyps and anatomical asymmetry degrade the mechanical vocal
fold properties and consequently disturb the normal oscillation pattern
resulting in an abnormal sound production. Treatment of voice abnormalities
would benefit from an improved understanding between the pathology and the
resulting oscillation pattern which motivates physical vocal folds modelling.
The current study applies a theoretical vocal folds model to vocal folds
pathologies. The theoretical vocal folds model is validated using an
experimental set-up simulating the human phonatory apparatus. It consists in a
pressure reservoir, a self-oscillating latex replica of the vocal folds and an
acoustical resonator. The effects of pathologies are simulated by modifying the
replica's geometry, elasticity, and homogeneity under controlled experimental
conditions. In general, we observed a close match between measurements and
theoretical predictions, which is all the more surprising considering the
crudeness of the theoretical model


title:
A mechanical experimental setup to simulate vocal folds vibrations.
  Preliminary results

abstract:
  This paper contributes to the understanding of vocal folds oscillation during
phonation. In order to test theoretical models of phonation, a new experimental
set-up using a deformable vocal folds replica is presented. The replica is
shown to be able to produce self sustained oscillations under controlled
experimental conditions. Therefore different parameters, such as those related
to elasticity, to acoustical coupling or to the subglottal pressure can be
quantitatively studied. In this work we focused on the oscillation fundamental
frequency and the upstream pressure in order to start (on-set threshold) either
end (off-set threshold) oscillations in presence of a downstream acoustical
resonator. As an example, it is shown how this data can be used in order to
test the theoretical predictions of a simple one-mass model.


title:
Diffractive photoproduction of Z^0 bosons in coherent interactions at
  CERN-LHC

abstract:
  The exclusive $Z^0$ photoproduction at high energies in $\gamma p (A)$, $p p$
and $AA$ collisions is investigate within the color dipole formalism. We
generalize the description of the deeply virtual compton scattering (DVCS)
process, which describe quite well the HERA data, for the production of $Z^0$
bosons and estimate the total cross section for the exclusive process $\gamma^*
h\to Z^0 h$ ($h=p,A$) for different energies, photon virtualities and atomic
numbers. As hadrons at collider energies are a source of Weizs\"{a}cker -
Williams photons, we consider electromagnetic interactions in hadron-hadron
collisions at Tevatron and LHC energies and estimate the rapidity distribution
and total cross section for $Z^0$ production in the $h h\to h Z^0 h$ process.
This is the first estimation for such a process in literature. It can allow us
to study, for instance, the physics of hadronic $Z^0$ decays in a clean
environment characterized by two rapidity gaps. Our results indicate that the
experimental analyzes of this process could be feasible in $pp$ but the physics
scenario for $AA$ collisions is not promising.


title:
Controllable switching of vortex chirality in magnetic nanodisks by a
  field pulse

abstract:
  We propose a way of fast switching the chirality in a magnetic nanodisk by
applying a field pulse. To break the symmetry with respect to clockwise or
counterclockwise chirality a mask is added by which an inhomogeneous field
influences the vortex state of a nanodisk. Using numerical spin--lattice
simulations we demonstrate that chirality can be controllably switched by a
field pulse, whose intensity is above some critical value. A mathematical
definition for the chirality of an arbitrary shaped particle is proposed.


title: Finite groups with an automorphism cubing a large fraction of elements

abstract:
  We investigate the possible structures imposed on a finite group by its
possession of an automorphism sending a large fraction of the group elements to
their cubes, the philosophy being that this should force the group to be, in
some sense, close to abelian. We prove two theorems. In the first, we
completely classify all finite groups with an automorphism cubing more than
half their elements. All such groups are either nilpotent class 2 or have an
abelian subgroup of index at most 2. For our second theorem we show that, if a
group possesses an automorphism sending more than 4/15 of its elements to their
cubes, then it must be solvable. The group A_5 shows that this result is best
possible.
  Both our main findings closely parallel results of previous authors on finite
groups possessing an automorphism which inverts many group elements. The
technicalities of the new proofs are somewhat more subtle, and also throw up a
nice connection to a basic problem in combinatorial number theory, namely the
study of subsets of finite cyclic groups which avoid non-trivial solutions to
one or more translation invariant linear equations.


title: Bounding dissipation in stochastic models

abstract:
  We generalize to stochastic dynamics the exact expression for average
dissipation along an arbitrary non-equilibrium process, given in Phys. Rev.
Lett. 98, 080602 (2007). We then derive lower bounds by various coarse-graining
procedures and illustrate how, when and where the information on the
dissipation is captured in models of over- and underdamped Brownian particles.


title: A Class of Monotonic Quantities along the Ricci Flow

abstract:
  We construct a class of monotonic quantities along the normalized Ricci flow
on closed n-dimensional manifolds.


title: Mesons in marginally deformed AdS/CFT

abstract:
  We study the embedding of spacetime filling D7-branes in beta-deformed
backgrounds which, according to the AdS/CFT dictionary, corresponds to
flavoring beta-deformed N=4 super Yang-Mills. We consider supersymmetric and
more general non-supersymmetric three parameter deformations. The equations of
motion for quadratic fluctuations of a probe D7-brane wrapped on a deformed
three-sphere exhibit a non-trivial coupling between scalar and vector modes
induced by the deformation. Nevertheless, we manage to solve them analytically
and find that the mesonic mass spectrum is discrete, with a mass gap and a
Zeeman-like splitting occurs. Finally we propose the action for the dual field
theory as obtained by star-product deformation of super Yang-Mills with
fundamental matter.


title: On the flavor structure of the littlest Higgs model

abstract:
  We investigate the Yukawa sector for up-like quarks in the Lee's version of
the Littlest Higgs model. We derive general quark mass and mixing formulae and
study leading order contributions due to non-zero light quark masses. Relying
on the unitarity of the generalized quark mixing matrix we obtain corrections
to the CKM matrix elements. In this model FCNCs appear at the tree level and
using leading order contributions we obtain the FCNC couplings for the up-like
quark transitions. In light of recent experimental results on the D0 - D0bar
transition we make predictions for xD as well as the D to mu+ mu- decay rate.
Finally, we discuss probabilities for the t to c (u) Z transitions relevant for
the LHC studies.


title: Long-Term Collisional Evolution of Debris Disks

abstract:
  We simulated the long-term collisional depletion of debris disks around
solar-type (G2V) stars with our code. The numerical results were supplemented
by, and interpreted through, a new analytic model. A few general scaling rules
for the disk evolution are suggested. The timescale of the collisional
evolution is inversely proportional to the initial disk mass and scales with
radial distance as r^4.3 and with eccentricities of planetesimals as e^-2.3.
Further, we show that at actual ages of debris disks between 10 Myr and 10 Gyr,
the decay of the dust mass and the total disk mass follow different laws. The
reason is that the collisional lifetime of planetesimals is size-dependent. At
any moment, there exists a transitional size, which separates larger objects
that still have the ``primordial'' size distribution set in the growth phase
from small objects whose size distribution is already set by disruptive
collisions. The dust mass and its decay rate evolve as that transition affects
objects of ever-larger sizes. Under standard assumptions, the dust mass,
fractional luminosity, and thermal fluxes all decrease as t^xi with xi =
-0.3...-0.4. Specific decay laws of the total disk mass and the dust mass,
including the value of xi, largely depend on a few model parameters, such as
the critical fragmentation energy as a function of size, the primordial size
distribution of largest planetesimals, as well as the characteristic
eccentricity and inclination of their orbits. With standard material
prescriptions and a distribution of disk masses and extents, a synthetic
population of disks generated with our analytic model agrees quite well with
the observed Spitzer/MIPS statistics of 24 and 70 micron fluxes and colors
versus age.


title:
Partial Differential system in two variables with
  $W(D_6^{(1)})$-symmetry and the Garnier system in two variables

abstract:
  In this note, we will compare the Garnier system in two variables with
four-dimensional partial differential system in two variables with
$W(D_6^{(1)})$-symmetry. Both systems are different in each compactification in
the variables $q_1,q_2$, however, has same five holomorphy conditions in the
variables $p_1,p_2$.


title: Determining the WIMP Mass from Direct Dark Matter Detection Data

abstract:
  Weakly interacting massive particles (WIMPs) are one of the leading
candidates for Dark Matter. So far we can use direct Dark Matter detection to
estimate the mass of halo WIMPs only by fitting predicted recoil spectra to
future experimental data. Here we develop a model-independent method for
determining the WIMP mass by using experimental data directly. This method is
independent of the as yet unknown WIMP density near the Earth as well as of the
WIMP-nuclear cross section and can be used to extract information about WIMP
mass with O(50) events.


title:
Asymptotics and singularities in cosmological models with positive
  cosmological constant

abstract:
  This thesis is concerned with global properties of those cosmological
solutions of Einstein's field equations which obey accelerated expansion into
the future driven by a non-vanishing cosmological constant, as suggested by
current cosmological observations. In particular, the strong cosmic censorship
and BKL conjecture are investigated in special classes of spacetimes. For this,
a new numerical technique based on spectral methods is introduced to be able to
deal with situations where the spatial topology is non-trivial from the
numerical point of view, such as the 3-sphere. Therefor, an explicit spectral
regularization at the - in single patch approaches inevitable - coordinate
singularities is worked out. After having collected the necessary background
material, including a description of the problems of interest, we discuss the
method and its implementation. Then we perform various tests, in particular
also in the presence of cosmological singularities. After that, the numerical
method is applied to obtain insights into three open issues in mathematical
cosmology: first, we make an attempt to describe the singularity structure in
Gowdy spacetimes with positive cosmological constants with spatial 3-sphere and
those with spatial 3-torus topology. Second, we perform a stability analysis of
Gowdy symmetry within the class of U(1)-symmetric spacetimes for spatial
3-sphere topology. Third, we make a preliminary analysis of the behavior of
certain $\lambda$-Taub-NUT Cauchy horizons under Gowdy perturbations. Finally,
we summarize the current status and open problems, and give an outlook.


title:
Two-Parameter Scaling of Microwave Rectification vs Microwave Power at
  the Boundary between Two-Dimensional Electron Systems

abstract:
  We report measurements of the rectification of microwave radiation (0.7-20
GHz) at the boundary between two-dimensional electron systems separated by a
narrow gap on a silicon surface for different temperatures, electron densities
and microwave power. For frequencies above 4 GHz and different temperatures,
the rectified voltage V_{dc} as a function of microwave power P can be scaled
onto a single universal curve V*_{dc}=f*(P*). The scaled voltage is a linear
function of power, V*_{dc} ~ P* for small power and proportional to P*^{1/2} at
higher power. A theory is proposed that attributes the rectification to the
thermoelectric response due to strong local overheating by the microwave
radiation at the boundary between two dissimilar 2D metals. Excellent agreement
is obtained between theory and experiment.


title: Stationary untrapped boundary conditions in general relativity

abstract:
  A class of boundary conditions for canonical general relativity are proposed
and studied at the quasi-local level. It is shown that for untrapped or
marginal surfaces, fixing the area element on the 2-surface (rather than the
induced 2-metric) and the angular momentum surface density is enough to have a
functionally differentiable Hamiltonian, thus providing definition of conserved
quantities for the quasi-local regions. If on the boundary the evolution vector
normal to the 2-surface is chosen to be proportional to the dual expansion
vector, we obtain a generalization of the Hawking energy associated with a
generalized Kodama vector. This vector plays the role for the stationary
untrapped boundary conditions which the stationary Killing vector plays for
stationary black holes. When the dual expansion vector is null, the boundary
conditions reduce to the ones given by the non-expanding horizons and the null
trapping horizons.


title: Odd Khovanov homology

abstract:
  We describe an invariant of links in the three-sphere which is closely
related to Khovanov's Jones polynomial homology. Our construction replaces the
symmetric algebra appearing in Khovanov's definition with an exterior algebra.
The two invariants have the same reduction modulo 2, but differ over the
rationals. There is a reduced version which is a link invariant whose graded
Euler characteristic is the normalized Jones polynomial.


title:
Interaction of massive black hole binaries with their stellar
  environment: III. Scattering of bound stars

abstract:
  We develop a formalism for studying the dynamics of massive black hole
binaries embedded in gravitationally-bound stellar cusps, and study the binary
orbital decay by three-body interactions, the impact of stellar slingshots on
the density profile of the inner cusp, and the properties of the ejected
hypervelocity stars (HVSs). We find that the scattering of bound stars shrinks
the binary orbit and increases its eccentricity more effectively than that of
unbound ambient stars. Binaries with initial eccentricities e>0.3 and/or
unequal-mass companions (M_2/M_1<0.1) can decay by three-body interactions to
the gravitational wave emission regime in less than a Hubble time. The stellar
cusp is significantly eroded, and cores as shallow as \rho\propto r^-0.7 may
develop from a pre-existing singular isothermal density profile. A population
of HVSs is ejected in the host galaxy halo, with a total mass ~M_2. We scale
our results to the scattering of stars bound to Sgr A*, the massive black hole
in the Galactic Center, by an inspiraling companion of intermediate mass.
Depending on binary mass ratio, eccentricity, and initial slope of the stellar
cusp, a core of radius ~0.1 pc typically forms in 1-10 Myr. On this timescale
about 500-2500 HVSs are expelled with speeds sufficiently large to escape the
gravitational potential of the Milky Way.


title: Theory of NMR in semiconductor quantum point contact devices

abstract:
  We describe how a local non-equilibrium nuclear polarisation can be generated
and detected by electrical means in a semiconductor quantum point contact
device. We show that measurements of the nuclear spin relaxation rate will
provide clear signatures of the interaction mechanism underlying the "0.7"
conductance anomaly. Our analysis illustrates how nuclear magnetic resonance
methods, which are used extensively to study strongly-correlated electron
phases in bulk materials, can be made to play a similarly important role in
nanoscale devices.


title: Theorie homotopique des DG-categories

abstract:
  In this thesis we present several original contributions to the study of:
  - DG categories and their invariants;
  - Neeman's well-generated (algebraic) triangulated categories;
  - Fomin-Zelevinsky's cluster algebras approach via representation theory.


title:
Belief propagation algorithm for computing correlation functions in
  finite-temperature quantum many-body systems on loopy graphs

abstract:
  Belief propagation -- a powerful heuristic method to solve inference problems
involving a large number of random variables -- was recently generalized to
quantum theory. Like its classical counterpart, this algorithm is exact on
trees when the appropriate independence conditions are met and is expected to
provide reliable approximations when operated on loopy graphs. In this paper,
we benchmark the performances of loopy quantum belief propagation (QBP) in the
context of finite-tempereture quantum many-body physics. Our results indicate
that QBP provides reliable estimates of the high-temperature correlation
function when the typical loop size in the graph is large. As such, it is
suitable e.g. for the study of quantum spin glasses on Bethe lattices and the
decoding of sparse quantum error correction codes.


title:
Bound-free pair production cross section in heavy-ion colliders from the
  equivalent photon approach

abstract:
  Exact calculations of the electron-positron pair production by a single
photon in the Coulomb field of a nucleus with simultaneous capture of the
electron into the K-shell are discussed for different nuclear charges. Using
the equivalent photon method of Weizsaecker and Williams, a simple expression
for the bound-free production of electron-positron pairs by colliding
very-high-energy fully stripped heavy ions is derived for nuclei of arbitrary
charge.


title:
Unifying dark components and crossing the phantom divide with a
  classical Dirac field

abstract:
  In this paper we consider a spatially flat Friedmann-Robertson-Walker (FRW)
cosmological model whit cosmological constant, containing a stiff fluid and a
classical Dirac field. The proposed cosmological scenario describes the
evolution of effective dark matter and dark energy components reproducing, with
the help of that effective multifluid configuration, the quintessential
behavior. We find the value of the scale factor where the effective dark energy
component crosses the phantom divide. The model we introduce, which can be
considered as a modified $\La$CDM one, is characterized by a set of parameters
which may be constrained by the astrophysical observations available up to
date.


title: The quermassintegral inequalities for starshaped domains

abstract:
  We give a simple proof of the insoperimetric inequality for quermassintegrals
of non-convex starshaped domains, using a reslut of Gerhardt \cite{G} and Urbas
\cite{U} on an expanding geometric curvature flow.


title:
Aharanov-Bohm excitons at elevated temperatures in type-II ZnTe/ZnSe
  quantum dots

abstract:
  Optical emission from type-II ZnTe/ZnSe quantum dots demonstrates large and
persistent oscillations in both the peak energy and intensity indicating the
formation of coherently rotating states. Furthermore, the Aharanov-Bohm (AB)
effect is shown to be remarkably robust and persists until 180K. This is at
least one order of magnitude greater than the typical temperatures in
lithographically defined rings. To our knowledge this is the highest
temperature at which the AB effect has been observed in semiconductor
structures.


title: Twisting on associative algebras and Rota-Baxter type operators

abstract:
  We will introduce an operation "twisting" on Hochschild complex by analogy
with Drinfeld's twisting operations. By using the twisting and derived bracket
construction, we will study differential graded Lie algebra structures
associated with bi-graded Hochschild complex. We will show that Rota-Baxter
type operators are solutions of Maurer-Cartan equations. As an application of
twisting, we will give a construction of associative Nijenhuis operators.


title: On two-Dimensional Holonomy

abstract:
  We define the thin fundamental categorical group ${\mathcal P}_2(M,*)$ of a
based smooth manifold $(M,*)$ as the categorical group whose objects are rank-1
homotopy classes of based loops on $M$, and whose morphisms are rank-2 homotopy
classes of homotopies between based loops on $M$. Here two maps are rank-$n$
homotopic, when the rank of the differential of the homotopy between them
equals $n$. Let $\C(\Gc)$ be a Lie categorical group coming from a Lie crossed
module ${\Gc= (\d\colon E \to G,\tr)}$. We construct categorical holonomies,
defined to be smooth morphisms ${\mathcal P}_2(M,*) \to \C(\Gc)$, by using a
notion of categorical connections, being a pair $(\w,m)$, where $\w$ is a
connection 1-form on $P$, a principal $G$ bundle over $M$, and $m$ is a 2-form
on $P$ with values in the Lie algebra of $E$, with the pair $(\w,m)$ satisfying
suitable conditions.
  As a further result, we are able to define Wilson spheres in this context.


title:
Enhanced symmetry points and metastable supersymmetry breaking along
  pseudo-runaway directions

abstract:
  We construct a model with long-lived metastable vacua in which all the
relevant parameters, including the supersymmetry breaking scale, are generated
dynamically by dimensional transmutation. The metastable vacua appear along a
pseudo-runaway direction near a point of enhanced symmetry as a result of a
balance between non-perturbative and perturbative quantum effects. We show that
metastable supersymmetry breaking is a rather generic feature near certain
enhanced symmetry points of gauge theory moduli spaces.


title:
Bulk thermodynamics and charge fluctuations at non-vanishing baryon
  density

abstract:
  We present results on bulk thermodynamic quantities as well as net baryon
number, strangeness and electric charge fluctuations in QCD at non-zero density
and temperature obtained from lattice calculations with almost physical quark
masses for two values of the lattice cut-off $aT=1/4$ and 1/6 . We show that
with our improved p4fa3-action the cut-off effects are under control when using
lattices with a temporal extent of 6 or larger and that the contribution to the
equation of state, which is due to a finite chemical potential is small for
$\mu_q/T<1$. Moreover, at vanishing chemical potential, i.e. under conditions
almost realized at RHIC and the LHC, quartic fluctuations of net baryon number
and strangeness are large in a narrow temperature interval characterizing the
transition region from the low to high temperature phase. At non-zero baryon
number density, strangeness fluctuations are enhanced and correlated to
fluctuations of the net baryon number. If strangeness is furthermore forced to
vanish, as it may be the case in systems created in heavy ion collisions,
strangeness fluctuations are significantly smaller than baryon number
fluctuations.


title: Superconductivity-induced macroscopic resonant tunneling

abstract:
  We show analytically and by numerical simulations that the conductance
through $\pi$-biased chaotic Josephson junctions is enhanced by several orders
of magnitude in the short-wavelength regime. We identify the mechanism behind
this effect as {\it macroscopic resonant tunneling} through a macroscopic
number of low-energy quasi-degenerate Andreev levels.


title: Substrate Adhesion of a Nongrafted Flexible Polymer in a Cavity

abstract:
  In a contact density chain-growth study we investigate the
solubility-temperature pseudo-phase diagram of a lattice polymer in a cavity
with an attractive surface. In addition to the main phases of adsorbed and
desorbed conformations we find numerous subphases of collapsed and expanded
structures.


title: Critical Collapse of Einstein Cluster

abstract:
  We observe critical phenomena in spherically symmetric gravitational collapse
of Einstein Cluster. We show analytically that the collapse evolution ends
either in formation of a black hole or in dispersal depending on the values of
initial parameters which characterize initial density and angular momentum of
the collapsing cloud. Near the threshold of black hole formation, we obtain
scaling relation for the mass of the black hole and find the critical exponent
value to be 3/2. We numerically confirm that there exist wide ranges of initial
parameter values around the critical configuration for which the model remains
shell-crossing free.


title:
Can the new Neutrino Telescopes reveal the Gravitational Properties of
  Antimatter?

abstract:
  We argue that the hypothesis of the gravitational repulsion between matter
and antimatter can be tested at the Ice Cube, a neutrino telescope, recently
constructed at the South Pole. If there is such a gravitational repulsion, the
gravitational field, deep inside the horizon of a black hole, might create
neutrino-antineutrino pairs from the quantum vacuum. While neutrinos must stay
confined inside the horizon, the antineutrinos should be violently ejected.
Hence, a black hole (made from matter) should behave as a point-like source of
antineutrinos. Our simplified calculations suggest, that the antineutrinos
emitted by supermassive black holes in the centre of the Milky Way and
Andromeda Galaxy, could be detected by the new generation of neutrino
telescopes.


title: One dimensional conformal metric flow II

abstract:
  In this paper we continue our studies of the one dimensional conformal metric
flows, which were introduced in [8]. In this part we mainly focus on evolution
equations involving fourth order derivatives. The global existence and
exponential convergence of metrics for the 1-Q and 4-Q flows are obtained.


title:
Differential invariants of a Lie group action: syzygies on a generating
  set

abstract:
  Given a group action, known by its infinitesimal generators, we exhibit a
complete set of syzygies on a generating set of differential invariants. For
that we elaborate on the reinterpretation of Cartan's moving frame by Fels and
Olver (1999). This provides constructive tools for exploring algebras of
differential invariants.


title:
Supersymmetric codimension-two branes in six-dimensional gauged
  supergravity

abstract:
  We consider the six-dimensional Salam-Sezgin supergravity in the presence of
codimension-2 branes. In the case that the branes carry only tension, we
provide a way to supersymmetrise them by adding appropriate localised
Fayet-Iliopoulos terms and localised corrections to the Chern-Simons term and
modifying accordingly the fermionic supersymmetry transformations. The
resulting brane action has N=1 supersymmetry (SUSY). We find the axisymmetric
vacua of the system and show that one has unwarped background solutions with
"football"-shaped extra dimensions which always respect N=1 SUSY for any value
of the equal brane tensions, in contrast with the non-supersymmetric brane
action background. Finally, we generically find multiple zero modes of the
gravitino in this background and discuss how one could obtain a single chiral
zero mode present in the low energy spectrum.


abstract:
  In this paper we shall give an analytic proof of the fact that the Liouville
energy on a topological two sphere is bounded from below. Our proof does not
rely on the uniformization theorem and the Onofri inequality, thus it is
essentially needed in the alternative proof of the uniformization theorem via
the Calabi flow. Such an analytic approach also sheds light on how to obtain
the boundedness for E_1 energy in the study of general K\"ahler manifolds.


title: Coarse Grained Liouville Dynamics of piecewise linear discontinuous maps

abstract:
  We compute the spectrum of the classical and quantum mechanical
coarse-grained propagators for a piecewise linear discontinuous map. We analyze
the quantum - classical correspondence and the evolution of the spectrum with
increasing resolution. Our results are compared to the ones obtained for a
mixed system.


title:
Exotic strange multibaryon states searches with $\Lambda$- hyperon and
  $K^0_s$- meson systems in p+A collisions at momentum 10 GeV/c

abstract:
  Review for exotic strange multibaryon states were obseved in the effective
mass spectra of: 1)$\Lambda \pi^+$, $\Lambda \pi^-$, $\Lambda p$, $\Lambda p
p$, and $\Lambda K^0_S$, $K^0_S\pi^{\pm}$ and $K^0_Sp$ subsystems.The invariant
mass of $\Lambda \pi^+$ and $K^0_S\pi^{\pm}$ spectra has observed well known
$\Sigma^{*+}$(1385) and $K^{*\pm}$(892) resonances. The width of
$\Sigma^{*-}(1385)$ for p+A reaction is two time larger than that presented in
PDG. The cross section of $\Xi^-\to \Lambda \pi^-$ is 7-8 times larger than
expected geometrical cross section in p+propane interaction. A few events
detected on the photographs of the propane bubble chamber, were interpreted as
S=-2 light and heavy $H^{0,+}$ dibaryons.


title:
Chain-Growth Simulations of Lattice-Peptide Adsorption to Attractive
  Substrates

abstract:
  Based on a newly developed contact-density chain-growth algorithm, we have
simulated a nongrafted peptide in the vicinity of different attractive
substrates. We analyzed the specificity of the peptide adsorption by focussing
on the conformational transitions the peptide experiences in the
binding/unbinding processes. In a single simulation run, we obtained the
contact density, i.e., the distribution of intrinsic monomer-monomer contacts
and monomer-substrate nearest-neighbor contacts. This allows a systematic
reweighting to all values of external control parameters such as temperature
and solvent quality after the simulation. The main result is the complete
solubility-temperature pseudo-phase diagram which is based on the corresponding
specific-heat profile. We find a surprisingly rich structure of pseudo-phases
that can roughly be classified into compact and expanded conformations in both
regimes, adsorption and desorption. Furthermore, underlying subphases were
identified, which, in particular, appear noticeably in the compact
pseudo-phases.


title: A sharp inequality and its applications

abstract:
  We establish an analog Hardy inequality with sharp constant involving
exponential weight function. The special case of this inequality (for n=2)
leads to a direct proof of Onofri inequality on S^2.


title:
Three-electron anisotropic quantum dots in variable magnetic fields:
  exact results for excitation spectra, spin structures, and entanglement

abstract:
  Exact-diagonalization calculations for N=3 electrons in anisotropic quantum
dots, covering a broad range of confinement anisotropies and strength of
inter-electron repulsion, are presented for zero and low magnetic fields. The
excitation spectra are analyzed as a function of the strength of the magnetic
field and for increasing quantum-dot anisotropy. Analysis of the intrinsic
structure of the many-body wave functions through spin-resolved two-point
correlations reveals that the electrons tend to localize forming Wigner
molecules. For certain ranges of dot parameters (mainly at strong anisotropy),
the Wigner molecules acquire a linear geometry, and the associated wave
functions with a spin projection S_z=1/2 are similar to the representative
class of strongly entangled states referred to as W-states. For other ranges of
parameters (mainly at intermediate anisotropy), the Wigner molecules exhibit a
more complex structure consisting of two mirror isosceles triangles. This
latter structure can be viewed as an embryonic unit of a zig-zag Wigner crystal
in quantum wires. The degree of entanglement in three-electron quantum dots can
be quantified through the use of the von Neumann entropy.

categories: cond-mat.mes-hall cond-mat.str-el physics.comp-ph quant-ph


title: Some Asymptotic Behavior of the first Eigenvalue along the Ricci Flow

abstract:
  We study some asymptotic behavior of the first nonzero eigenvalue of the
Lalacian along the normalized Ricci flow and give a direct short proof for an
asymptotic upper limit estimate.