title:
Unsymmetrical and symmetrical one-range addition theorems for Slater
  type orbitals and Coulomb-Yukawa like correlated interaction potentials of
  integer and noninteger indices

abstract:
  Using one-center expansion relations for the Slater type orbitals (STOs) of
noninteger principal quantum numbers in terms of integer n STOs derived in this
study with the help of - exponential type orbitals (-ETOs, the general formulas
are established for the unsymmetrical and symmetrical one-range addition
theorems of STOs and Coulomb-Yukawa like correlated interaction potentials
(CIPs) with integer and noninteger indices. The final results are especially
useful for computations of arbitrary multicenter multielectron integrals over
STOs that arise in the Hartree-Fock-Roothaan (HFR) approximation and also in
the correlated methods which play a significant role in theory and application
to quantum mechanics of atoms, molecules, and solids.


title: Ricci Flow of Biaxial Bianchi IX Metrics

abstract:
  We use the Ricci flow with surgery to study four-dimensional SU(2) x
U(1)-symmetric metrics on a manifold with fixed boundary given by a squashed
3-sphere. Depending on the initial metric we show that the flow converges to
either the Taub-Bolt or the Taub-NUT metric, the latter case potentially
requiring surgery at some point in the evolution. The Ricci flow allows us to
explore the Euclidean action landscape within this symmetry class. This work
extends the recent work of Headrick and Wiseman to more interesting topologies.


title: Long-time convergence of an Adaptive Biasing Force method

abstract:
  We propose a proof of convergence of an adaptive method used in molecular
dynamics to compute free energy profiles. Mathematically, it amounts to
studying the long-time behavior of a stochastic process which satisfies a
non-linear stochastic differential equation, where the drift depends on
conditional expectations of some functionals of the process. We use entropy
techniques to prove exponential convergence to the stationary state.


title: Minimal Walking Technicolor: Set Up for Collider Physics

abstract:
  Different theoretical and phenomenological aspects of the Minimal and
Nonminimal Walking Technicolor theories have recently been studied. The goal
here is to make the models ready for collider phenomenology. We do this by
constructing the low energy effective theory containing scalars, pseudoscalars,
vector mesons and other fields predicted by the minimal walking theory. We
construct their self-interactions and interactions with standard model fields.
Using the Weinberg sum rules, opportunely modified to take into account the
walking behavior of the underlying gauge theory, we find interesting relations
for the spin-one spectrum. We derive the electroweak parameters using the newly
constructed effective theory and compare the results with the underlying gauge
theory. Our analysis is sufficiently general such that the resulting model can
be used to represent a generic walking technicolor theory not at odds with
precision data.


title:
Equations of motion approach to the spin-1/2 Ising model on the Bethe
  lattice

abstract:
  We exactly solve the ferromagnetic spin-1/2 Ising model on the Bethe lattice
in the presence of an external magnetic field by means of the equations of
motion method within the Green's function formalism. In particular, such an
approach is applied to an isomorphic model of localized Fermi particles
interacting via an intersite Coulomb interaction. A complete set of
eigenoperators is found together with the corresponding eigenvalues. The
Green's functions and the correlation functions are written in terms of a
finite set of parameters to be self-consistently determined. A procedure is
developed, that allows us to exactly fix the unknown parameters in the case of
a Bethe lattice with any coordination number z. Non-local correlation functions
up to four points are also provided together with a study of the relevant
thermodynamic quantities.


title:
The Explicit Chaotic Representation of the powers of increments of Levy
  Processes

abstract:
  An explicit formula for the chaotic representation of the powers of
increments, (X_{t+t_0}-X_{t_0})^n, of a Levy process is presented. There are
two different chaos expansions of a square integrable functional of a Levy
process: one with respect to the compensated Poisson random measure and the
other with respect to the orthogonal compensated powers of the jumps of the
Levy process. Computationally explicit formulae for both of these chaos
expansions of (X_{t+t_0}-X_{t_0})^n are given in this paper. Simulation results
verify that the representation is satisfactory. The CRP of a number of
financial derivatives can be found by expressing them in terms of
(X_{t+t_0}-X_{t_0})^n using Taylor's expansion.


title: OPERA first events from the CNGS neutrino beam

abstract:
  The aim of the OPERA experiment is to search for the appearance of the tau
neutrino in the quasi pure muon neutrino beam produced at CERN (CNGS). The
detector, installed in the Gran Sasso underground laboratory 730 km away from
CERN, consists of a lead/emulsion target complemented with electronic
detectors. A report is given on the detector status (construction, data taking
and analysis) and on the first successful 2006 neutrino runs.


title:
Information Criteria and Arithmetic Codings : An Illustration on Raw
  Images

abstract:
  In this paper we give a short theoretical description of the general
predictive adaptive arithmetic coding technique. The links between this
technique and the works of J. Rissanen in the 80's, in particular the BIC
information criterion used in parametrical model selection problems, are
established. We also design lossless and lossy coding techniques of images. The
lossless technique uses a mix between fixed-length coding and arithmetic coding
and provides better compression results than those separate methods. That
technique is also seen to have an interesting application in the domain of
statistics since it gives a data-driven procedure for the non-parametrical
histogram selection problem. The lossy technique uses only predictive adaptive
arithmetic codes and shows how a good choice of the order of prediction might
lead to better results in terms of compression. We illustrate those coding
techniques on a raw grayscale image.


title: Constraints, MMSNP and expander relational structures

abstract:
  We give a poly-time construction for a combinatorial classic known as Sparse
Incomparability Lemma, studied by Erdos, Lovasz, Nesetril, Rodl and others: We
show that every Constraint Satisfaction Problem is poly-time equivalent to its
restriction to structures with large girth. This implies that the complexity
classes CSP and Monotone Monadic Strict NP introduced by Feder and Vardi are
computationally equivalent. The technical novelty of the paper is a concept of
expander relations and a new type of product for relational structures: a
generalization of the zig-zag product, the twisted product.


title: Theory of the Pseudospin Resonance in Semiconductor Bilayers

abstract:
  The pseudospin degree of freedom in a semiconductor bilayer gives rise to a
collective mode analogous to the ferromagnetic resonance mode of a ferromagnet.
We present a theory of the dependence of the energy and the damping of this
mode on layer separation $d$. Based on these results, we discuss the
possibility of realizing transport-current driven pseudospin-transfer
oscillators in semiconductors.


title: Correlation between galactic HI and the Cosmic Microwave Background

abstract:
  We revisit the issue of a correlation between the atomic hydrogen gas in our
local Galaxy and the Cosmic Microwave Background (CMB), a detection of which
has been claimed in some literature. We cross-correlate the 21-cm emission of
Galactic atomic hydrogen as traced by the Leiden/Argentine/Bonn Galactic HI
survey with the 3-year CMB data from the Wilkinson Microwave Anisotropy Probe.
We consider a number of angular scales, masks, and HI velocity slices and find
no statistically significant correlation.


title: Forbidden lists (NP and CSP for combinatorialists)

abstract:
  We present a definition of the class NP in combinatorial context as the set
of languages of structures defined by finitely many forbidden lifted
substructures. We apply this to special syntactically defined subclasses and
show how they correspond to naturally defined (and intensively studied)
combinatorial problems. We show that some types of combinatorial problems like
edge colorings and graph decompositions express the full computational power of
the class NP. We then characterize Constraint Satisfaction Problems (i.e.
H-coloring problems) which are expressible by finitely many forbidden lifted
substructures. This greatly simplifies and generalizes the earlier attempts to
characterize this problem. As a corollary of this approach we perhaps find a
proper setting of Feder and Vardi analysis of CSP languages within the class
MMSNP.


title:
Investigations of Ra$^+$ properties to test possibilities of new optical
  frequency standards

abstract:
  The present work tests the suitability of the narrow transitions $7s \
^2S_{1/2} \to 6d ^2D_{3/2}$ and $7s ^2S_{1/2} \to 6d ^2D_{5/2}$ in Ra$^+$ for
optical frequency standard studies. Our calculations of the lifetimes of the
metastable $6d$ states using the relativistic coupled-cluster theory suggest
that they are sufficiently long for Ra$^+$ to be considered as a potential
candidate for an atomic clock. This is further corroborated by our studies of
the hyperfine interactions, dipole and quadrupole polarizabilities and
quadrupole moments of the appropriate states of this system.


title:
Spatiotemporal structure of Lyapunov vectors in chaotic coupled-map
  lattices

abstract:
  The spatiotemporal dynamics of Lyapunov vectors (LVs) in spatially extended
chaotic systems is studied by means of coupled-map lattices. We determine
intrinsic length scales and spatiotemporal correlations of LVs corresponding to
the leading unstable directions by translating the problem to the language of
scale-invariant growing surfaces. We find that the so-called 'characteristic'
LVs exhibit spatial localization, strong clustering around given spatiotemporal
loci, and remarkable dynamic scaling properties of the corresponding surfaces.
In contrast, the commonly used backward LVs (obtained through Gram-Schmidt
orthogonalization) spread all over the system and do not exhibit dynamic
scaling due to artifacts in the dynamical correlations by construction.


title: The centrality dependence of elliptic flow at LHC

abstract:
  We present predictions for the centrality dependence of elliptic flow at
mid-rapidity in Pb-Pb collisions at the LHC.


title: Effective Actions of IIB Matrix Model on S^3

abstract:
  S^3 is a simple principle bundle which is locally S^2 \times S^1. It has been
shown that such a space can be constructed in terms of matrix models. It has
been also shown that such a space can be realized by a generalized
compactification procedure in the S^1 direction. We investigate the effective
action of supersymmetric gauge theory on S^3 with an angular momentum cutoff
and that of a matrix model compactification. The both cases can be realized in
a deformed IIB matrix model with a Myers Term. We find that the highly
divergent contributions at the tree and one loop level are sensitive to the uv
cutoff. However the two loop level contributions are universal since they are
only logarithmically divergent. We expect that the higher loop contributions
are insensitive to the uv cutoff since 3d gauge theory is super renormalizable.


title:
The Higher Order Schwarzian Derivative: Its Applications for Chaotic
  Behavior and New Invariant Sufficient Condition of Chaos

abstract:
  The Schwarzian derivative of a function f(x) which is defined in the interval
(a, b) having higher order derivatives is given by
Sf(x)=(f''(x)/f'(x))'-1/2(f''(x)/f'(x))^2 . A sufficient condition for a
function to behave chaotically is that its Schwarzian derivative is negative.
In this paper, we try to find a sufficient condition for a non-linear dynamical
system to behave chaotically. The solution function of this system is a higher
degree polynomial. We define n-th Schwarzian derivative to examine its general
properties. Our analysis shows that the sufficient condition for chaotic
behavior of higher order polynomial is provided if its highest order three
terms satisfy an inequality which is invariant under the degree of the
polynomial and the condition is represented by Hankel determinant of order 2.
Also the n-th order polynomial can be considered to be the partial sum of real
variable analytic function. Let this analytic function be the solution of
non-linear differential equation, then the sufficient condition for the
chaotical behavior of this function is the Hankel determinant of order 2
negative, where the elements of this determinant are the coefficient of the
terms of n, n-1, n-2 in Taylor expansion.


title:
New method for atmospheric calibration at the Pierre Auger Observatory
  using FRAM, a robotic astronomical telescope

abstract:
  FRAM - F/(Ph)otometric Robotic Atmospheric Monitor is the latest addition to
the atmospheric monitoring instruments of the Pierre Auger Observatory. An
optical telescope equipped with CCD camera and photometer, it automatically
observes a set of selected standard stars and a calibrated terrestrial source.
Primarily, the wavelength dependence of the attenuation is derived and the
comparison between its vertical values (for stars) and horizontal values (for
the terrestrial source) is made. Further, the integral vertical aerosol optical
depth can be obtained. A secondary program of the instrument, the detection of
optical counterparts of gamma-ray bursts, has already proven successful. The
hardware setup, software system, data taking procedures, and first analysis
results are described in this paper.


title:
Ergodicity of the extended anisotropic 1D Heisenberg model: response at
  low temperatures

abstract:
  We present the results of exact diagonalization calculations of the isolated
and isothermal on-site static susceptibilities in the anisotropic extended
Heisenberg model on a linear chain with periodic boundary conditions. Based on
the ergodicity considerations we conclude that the isothermal susceptibility
will diverge as $T\to 0$ both in finite clusters and in the bulk system in two
non-ergodic regions of the phase diagram of the system.


title: Test Functions Space in Noncommutative Quantum Field Theory

abstract:
  It is proven that the $\star$-product of field operators implies that the
space of test functions in the Wightman approach to noncommutative quantum
field theory is one of the Gel'fand-Shilov spaces $S^{\beta}$ with $\beta <
1/2$. This class of test functions smears the noncommutative Wightman
functions, which are in this case generalized distributions, sometimes called
hyperfunctions. The existence and determination of the class of the test
function spaces in NC QFT is important for any rigorous treatment in the
Wightman approach.


title:
Dynamics of the giant planets of the solar system in the gaseous
  proto-planetary disk and relationship to the current orbital architecture

abstract:
  We study the orbital evolution of the 4 giant planets of our solar system in
a gas disk. Our investigation extends the previous works by Masset and
Snellgrove (2001) and Morbidelli and Crida (2007, MC07), which focussed on the
dynamics of the Jupiter-Saturn system. The only systems that we found to reach
a steady state are those in which the planets are locked in a quadruple mean
motion resonance (i.e. each planet is in resonance with its neighbor). In total
we found 6 such configurations. For the gas disk parameters found in MC07,
these configurations are characterized by a negligible migration rate. After
the disappearance of the gas, and in absence of planetesimals, only two of
these six configurations (the least compact ones) are stable for a time of
hundreds of millions of years or more. The others become unstable on a
timescale of a few My. Our preliminary simulations show that, when a
planetesimal disk is added beyond the orbit of the outermost planet, the
planets can evolve from the most stable of these configurations to their
current orbits in a fashion qualitatively similar to that described in Tsiganis
et al. (2005).


title:
Theory of nonlinear particle acceleration at shocks and self-generation
  of the magnetic field

abstract:
  We present some recent developments in the theory of particle acceleration at
shock fronts in the presence of dynamical reaction of the accelerated particles
and self-generation of magnetic field due to streaming instability. The spectra
of accelerated particles, the velocity, magnetic field and temperature profiles
can be calculated in this approach anywhere in the precursor and in the
downstream region. The implications for the origin of cosmic rays and for the
phenomenology of supernova remnants will be discussed.


title:
Search for correlation of UHECRs and BL Lacs in Pierre Auger Observatory
  data

abstract:
  Several analyses of the data collected by other experiments have found an
excess of cosmic rays in correlation with subclasses of BL Lacs. Data from the
Pierre Auger Observatory do not support previously reported excesses. The
number of events correlated with BL Lac positions is compatible with that
expected for an isotropic flux.


title: Modeling and analysis using hybrid Petri nets

abstract:
  This paper is devoted to the use of hybrid Petri nets (PNs) for modeling and
control of hybrid dynamic systems (HDS). Modeling, analysis and control of HDS
attract ever more of researchers' attention and several works have been devoted
to these topics. We consider in this paper the extensions of the PN formalism
(initially conceived for modeling and analysis of discrete event systems) in
the direction of hybrid modeling. We present, first, the continuous PN models.
These models are obtained from discrete PNs by the fluidification of the
markings. They constitute the first steps in the extension of PNs toward hybrid
modeling. Then, we present two hybrid PN models, which differ in the class of
HDS they can deal with. The first one is used for deterministic HDS modeling,
whereas the second one can deal with HDS with nondeterministic behavior.
Keywords: Hybrid dynamic systems; D-elementary hybrid Petri nets; Hybrid
automata; Controller synthesis


title:
Comment on the paper by Rovelli & al. about the compatibility of various
  "gauge conditions"

abstract:
  The compatibility "demonstrated" by Rovelli & al. between various "gauge
conditions" both in Classical Electromagnetism and General Relativity can be
better understood if one distinguishes "gauge conditions" of the solution type
and "gauge conditions" of the constraint type.


title: The Strehl Ratio in Adaptive Optics Images: Statistics and Estimation

abstract:
  Statistical properties of the intensity in adaptive optics images are usually
modeled with a Rician distribution. We study the central point of the image,
where this model is inappropriate for high to very high correction levels. The
central point is an important problem because it gives the Strehl ratio
distribution. We show that the central point distribution can be modeled using
a non-central Gamma distribution.


title:
Systematic study of atmosphere-induced influences and uncertainties on
  shower reconstruction at the Pierre Auger Observatory

abstract:
  A wide range of atmospheric monitoring instruments is employed at the Pierre
Auger Observatory: two laser facilities, elastic lidar stations, aerosol phase
function monitors, a horizontal attenuation monitor, star monitors, weather
stations, and balloon soundings. We describe the impact of analyzed atmospheric
data on the accuracy of shower reconstructions, and in particular study the
effect of the data on the shower energy and the depth of shower maximum (Xmax).
These effects have been studied using the subset of golden hybrid events -
events observed with high quality in the fluorescence and surface detector -
used in the calibration of the surface detector energy spectrum.


title:
Correction of paper published in J. Combinatorial Theory 21, 1976: On
  the Existence of Hadamard Matrices

abstract:
  In the paper On the Existence of Hadamard Matrices in J. Combinatorial Theory
21, 1976, it is shown that for a natural number q > 3, we can construct an
Hadamard Matrix of order 2^s q for s \geq t where t = [2 log_2(q-3)]. I will
show that this bound is not a consequence of the proof given in the paper and
explain the error in the argumentation.


title: Geometric Origin of Physical Constants in a Kaluza-Klein Tetrad Model

abstract:
  An important feature of Kaluza-Klein theories is their ability to relate
fundamental physical constants to the radii of higher dimensions. In previous
Kaluza-Klein theory, which unifies the electromagnetic field with gravity as
dimensionless components of a Kaluza-Klein metric, i) all fields have the same
physical dimensions, ii) the Lagrangian has no explicit dependence on any
physical constants except mass, and hence iii) all physical constants in the
field equations except for mass originate from geometry. While it seems natural
in Kaluza-Klein theory to add fermion fields by defining higher dimensional
bispinor fields on the Kaluza-Klein manifold, these Kaluza-Klein theories do
not satisfy conditions (i), (ii), and (iii). In this paper, we show how
conditions (i), (ii), and (iii) can be satisfied by including bispinor fields
in a tetrad formulation of the Kaluza-Klein model, as well as in an equivalent
teleparallel model. This demonstrates an unexpected feature of Dirac's bispinor
equation, since conditions (i), (ii), (iii) imply a special relation among the
terms in the Kaluza-Klein or teleparallel Lagrangian that would not be
satisfied in general.


title:
A kinetic approach to non resonant modes and growth rates of streaming
  instability: consequences for shock acceleration

abstract:
  We show here that a purely kinetic approach to the excitation of waves by
cosmic rays in the vicinity of a shock front leads to predict the appearance of
a non-alfvenic fastly growing mode which is the same that was found by Bell
(2004) by treating the plasma in the MHD approximation. The kinetic approach we
present is more powerful in that it allows us to investigate different models
for the compensation of the cosmic ray current in the background upstream
plasma.


title:
Ehrlich-Schwoebel Effect for Organic Molecules: Direct Calculation of
  the Step Edge Barrier using Empirical Potentials

abstract:
  The step edge barrier of a prototypical organic semiconductor molecule,
3,4,9,10-perylene-tetracaboxylic-dianhydride (PTCDA) has been analysed by means
of calculations based on emperical potentials. The minimum energy path (MEP)
has been calculated for a single molecule on a substrate of three molecular
layers between equivalent minimum energy positions within two neighboring unit
cells. To determine the step edge barrier, we have calculated the MEP over a
step to a fourth layer of molecules. We found energy barriers of E_D= 80 meV
for in-layer diffusion and E_S = 750 meV for step crossing, indicating a strong
Ehrlich-Schwoebel effect for PTCDA.


title: Star formation in Perseus: III. Outflows

abstract:
  We present a search for outflows towards 51 submillimetre cores in Perseus.
With consistently derived outflow properties from a large homogeneous dataset
within one molecular cloud we can investigate further the mass dependence and
time evolution of protostellar mass loss. Of the 51 cores, 37 show broad
linewings indicative of molecular outflows. In 13 cases, the linewings could be
due to confusion with neighbouring flows but 9 of those sources also have
near-infrared detections confirming their protostellar nature. The total
fraction of protostars in our sample is 65%. All but four outflow detections
are confirmed as protostellar by Spitzer IR detections and only one Spitzer
source has no outflow, showing that outflow maps at this sensitivity are
equally good at identifying protostars as Spitzer. Outflow momentum flux
correlates both with source luminosity and with core mass but there is
considerable scatter even within this one cloud despite the homogeneous
dataset. We fail to confirm the result of Bontemps et al. (1996) that Class I
sources show lower momentum fluxes on average than Class 0 sources, with a KS
test showing a significant probability that the momentum fluxes for both Class
0s and Class Is are drawn from the same distribution. We find that outflow
power may not show a simple decline between the Class 0 to Class I stages. Our
sample includes low momentum flux, low-luminosity Class 0 sources, possibly at
a very early evolutionary stage. If the only mass loss from the core were due
to outflows, cores would last for 10^5-10^8 years, longer than current
estimates of 1.5-4 x 10^5 years for the mean lifetime for the embedded phase.
Additional mechanisms for removing mass from protostellar cores may be
necessary.


title: The two possible values of the chromatic number of a random graph

abstract:
  Given d \in (0,infty) let k_d be the smallest integer k such that d < 2k\log
k. We prove that the chromatic number of a random graph G(n,d/n) is either k_d
or k_d+1 almost surely.


title:
High Precision determination of the pi, K, D and D_s decay constants
  from lattice QCD

abstract:
  We determine $D$ and $D_s$ decay constants from lattice QCD with 2% errors, 4
times better than experiment and previous theory: $f_{D_s}$ = 241(3) MeV, $f_D$
= 207(4) MeV and $f_{D_s}/f_D$ = 1.164(11).
  We also obtain $f_K/f_{\pi}$ = 1.189(7) and $(f_{D_s}/f_D)/(f_K/f_{\pi})$ =
0.979(11). Combining with experiment gives $V_{us}$=0.2262(14) and
$V_{cs}/V_{cd}$ of 4.43(41). We use a highly improved quark discretization on
MILC gluon fields that include realistic sea quarks fixing the $u/d, s$ and $c$
masses from the $\pi$, $K$, and $\eta_c$ meson masses. This allows a stringent
test against experiment for $D$ and $D_s$ masses for the first time (to within
7 MeV).


title: Comment on "Elementary Kaluza-Klein towers revisited"

abstract:
  Recently the spectrum of KK modes in the framework of one flat
extra-dimensional scenario was revisited in the paper Phys. Rev. D74 (2006)
124013, (hep-th/0607246) on the basis of self-adjoint extension of the quantum
mechanical operator determining the KK masses. In this Letter we note that the
range of allowed boundary conditions on the KK modes is overestimated in above
mentioned paper and give all allowed possibilities.


title: Lambda Mu Calculus and Duality: Call-by-Name and Call-by-Value

abstract:
  Under the extension of Curry-Howard's correspondence to classical logic,
Gentzen's NK and LK systems can be seen as syntax-directed systems of simple
types respectively for Parigot's Lambda Mu Calculus and Curien-Herbelin's
Lambda Bar Mu Mu Tidle Calculus. We aim at showing their computational
equivalence. We define translations between these calculi. We prove simulation
theorems for an undirected evaluation as well as for call-by-name and
call-by-value evaluations.


title:
Mixing angles of quarks and leptons as an outcome of SU(2) horizontal
  symmetries

abstract:
  We show that all mixing angles are determined, within experimental
uncertainty, by a product of SU(2) horizontal symmetries intimately linked to
the algebra of weak neutral currents. This concerns: on one hand, the three
quark mixing angles; on the other hand, a neutrino-like pattern in which
theta_{23} is maximal and tan (2 theta_{12}) = 2. The latter turns out to
exactly satisfy the ``quark-lepton complementarity condition'' theta_c +
theta_{12} = pi/4. Moreover, among all solutions, two values for the third
neutrino mixing angle arise, which satisfy the bound sin^2(theta_{13}) \leq
0.1: theta_{13} = +/- 5.7 10^{-3} and theta_{13} = +/- 0.2717.


title: Global well-posedness for dissipative Korteweg-de Vries equations

abstract:
  This paper is devoted to the well-posedness for dissipative KdV equations
$u_t+u_{xxx}+|D_x|^{2\alpha}u+uu_x=0$, $0<\alpha\leq 1$. An optimal bilinear
estimate is obtained in Bourgain's type spaces, which provides global
well-posedness in $H^s(\R)$, $s>-3/4$ for $\alpha\leq1/2$ and
$s>-3/(5-2\alpha)$ for $\alpha>1/2$.


title:
The VLT-FLAMES survey of massive stars: Evolution of surface N
  abundances and effective temperature scales in the Galaxy and Magellanic
  Clouds

abstract:
  We present an analysis of high resolution VLT-FLAMES spectra of 61 B-type
stars with relatively narrow-lined spectra located in 4 fields centered on the
Milky Way clusters; NGC3293 & NGC4755 and the Large and Small Magellanic cloud
clusters; NGC2004 and NGC330. For each object a quantitative analysis was
carried out using the non-LTE model atmosphere code TLUSTY; resulting in the
determination of their atmospheric parameters and photospheric abundances of
the dominant metal species (C, N, O, Mg, Si, Fe). The results are discussed in
relation to our earlier work on 3 younger clusters in these galaxies; NGC6611,
N11 and NGC346 paying particular attention to the nitrogen abundances which are
an important probe of the role of rotation in the evolution of stars. This work
along with that of the younger clusters provides a consistent dataset of
abundances and atmospheric parameters for over 100 B-type stars in the three
galaxies. We provide effective temperature scales for B-type dwarfs in all
three galaxies and for giants and supergiants in the SMC and LMC. In each
galaxy a dependence on luminosity is found between the three classes with the
unevolved dwarf objects having significantly higher effective temperatures. A
metallicity dependence is present between the SMC and Galactic dwarf objects,
and whilst the LMC stars are only slightly cooler than the SMC stars, they are
significantly hotter than their Galactic counterparts.


title:
GeV Seesaw, Accidentally Small Neutrino Masses, and Higgs Decays to
  Neutrinos

abstract:
  If the Standard Model particle content is extended by gauge singlet fermions
(right-handed neutrinos), active neutrinos generically acquire (Majorana)
masses, in agreement with our current understanding of the lepton sector. If
the right-handed neutrino masses are of the same order as the electroweak
symmetry breaking scale, it is usually expected that these will not mediate any
experimentally observable effects. Here, I explore the fact that this is not
necessarily the case. If neutrino masses are "accidentally small",
active-sterile mixing angles can, according to current experimental bounds, be
as large as several percent. If this is the case, I argue that the dominant
decay mode of light (M_H less than 130 GeV) Higgs bosons could be into an
active and a sterile neutrino. The sterile neutrino decays promptly into a
charge lepton and an on- or off-shell W-boson, so that the dominant Higgs boson
decay mode is H to leptons + jets + missing transverse energy.


title:
Magnetic fingerprint in a ferromagnetic wire: Spin torque diode effect
  and induction of the DC voltage spectrum inherent in the wire under
  application for RF current

abstract:
  We report the rectifying effect of a constant-wave radio frequency (RF)
current by a magnetic domain wall (DW) on a single-layered ferromagnetic wire.
A direct-current (DC) voltage is generated by the spin torque diode effect,
which is a consequence of magnetoresistance oscillation due to the resonant
spin wave excitation induced by the spin-polarized RF current. The DC voltage
spectrum strongly depends on the internal spin structure in the DW, which
corresponds to the magnetic fingerprint of the spin structure in the
ferromagnetic wire.


title:
The new very small angle neutron scattering spectrometer at Laboratoire
  Leon Brillouin

abstract:
  The design and characteristics of the new very small angle neutron scattering
spectrometer under construction at the Laboratoire Leon Brillouin is described.
Its goal is to extend the range of scattering vectors magnitudes towards
2x10{-4} /A. The unique feature of this new spectrometer is a high resolution
two dimensional image plate detector sensitive to neutrons. The wavelength
selection is achieved by a double reflection supermirror monochromator and the
collimator uses a novel multibeam design.


title: Self Replication and Signalling

abstract:
  It is known that if one could clone an arbitrary quantum state one could send
signal faster than the speed of light. However it remains interesting to see
that if one can perfectly self replicate an arbitrary quantum state, does it
violate the no signalling principle? Here we see that perfect self replication
would also lead to superluminal signalling.


title: Gilbert and Landau-Lifshitz damping in the presense of spin-torque

abstract:
  A recent article by Stiles et al. (cond-mat/0702020) argued in favor of the
Landau-Lifshitz damping term in the micromagnetic equations of motion over that
of the more commonly accepted Gilbert damping form. Much of their argument
revolved around spin-torque driven domain wall motion in narrow magnetic wires,
since the presence of spin-torques can more acutely draw a distinction between
the two forms of damping. In this article, the author uses simple arguments and
examples to offer an alternative point of view favoring Gilbert.


title: Noise enhancement due to quantum coherence in coupled quantum dots

abstract:
  We show that the intriguing observation of noise enhancement in the charge
transport through two vertically coupled quantum dots can be explained by the
interplay of quantum coherence and strong Coulomb blockade. We demonstrate that
this novel mechanism for super-Poissonian charge transfer is very sensitive to
decoherence caused by electron-phonon scattering as inferred from the measured
temperature dependence.


title: Permutations with Extremal number of Fixed Points

abstract:
  We extend Stanley's work on alternating permutations with extremal number of
fixed points in two directions: first, alternating permutations are replaced by
permutations with a prescribed descent set; second, instead of simply counting
permutations we study their generating polynomials by number of excedances.
Several techniques are used: Desarmenien's desarrangement combinatorics,
Gessel's hook-factorization and the analytical properties of two new
permutation statistics "DEZ" and "lec". Explicit formulas for the maximal case
are derived by using symmetric function tools.


title: Speckle noise and dynamic range in coronagraphic images

abstract:
  This paper is concerned with the theoretical properties of high contrast
coronagraphic images in the context of exoplanet searches. We derive and
analyze the statistical properties of the residual starlight in coronagraphic
images, and describe the effect of a coronagraph on the speckle and photon
noise. Current observations with coronagraphic instruments have shown that the
main limitations to high contrast imaging are due to residual quasi-static
speckles. We tackle this problem in this paper, and propose a generalization of
our statistical model to include the description of static, quasi-static and
fast residual atmospheric speckles. The results provide insight into the
effects on the dynamic range of wavefront control, coronagraphy, active speckle
reduction, and differential speckle calibration. The study is focused on
ground-based imaging with extreme adaptive optics, but the approach is general
enough to be applicable to space, with different parameters.


title: On path factors of (3,4)-biregular bigraphs

abstract:
  A (3,4)-biregular bigraph G is a bipartite graph where all vertices in one
part have degree 3 and all vertices in the other part have degree 4. A path
factor of G is a spanning subgraph whose components are nontrivial paths. We
prove that a simple (3,4)-biregular bigraph always has a path factor such that
the endpoints of each path have degree three. Moreover we suggest a polynomial
algorithm for the construction of such a path factor.


title: Breakdown of the Thomas Fermi approximation for polarized Fermi gases

abstract:
  We use Bogoliubov de-Gennes theory to show that the commonly used
Thomas-Fermi approximation (TFA) can fail in describing polarized unitary gases
in anisotropic harmonic traps. We find a magnetized superfluid region inside
the trap, with order parameter oscillations, even though there is no such
stable bulk phase. This leads to magnetization profiles that deviate from
contours of constant potential energy. We determine how this violation scales
with trap anisotropy and number of particles, and show that we are able to
account for important differences between the MIT and Rice experiments.


title:
Intrinsic nanoscale inhomogeneity in ordering systems due to
  elastic-mediated interactions

abstract:
  Phase diagram and pattern formation in two-dimensional Ising model with
coupling between order parameter and lattice vibrations is investigated by
Monte-Carlo simulations. It is shown that if the coupling is strong enough (or
phonons are soft enough) a short-range order exists in disordered phase for a
broader temperature interval. Different types of this short-range order
(stripe-like, checkboard-like, etc.) depending on the temperature and model
parameters are investigated. With further increase of the coupling, a
reconstruction of the ground state happens and new ordered phases appear at low
enough temperatures.


title: Bloch vectors for qudits and geometry of entanglement

abstract:
  We present three different matrix bases that can be used to decompose density
matrices of d--dimensional quantum systems, so-called qudits: the generalized
Gell-Mann matrix basis, the polarization operator basis, and the Weyl operator
basis. Such a decomposition can be identified with a vector --the Bloch vector,
i.e. a generalization of the well known qubit case-- and is a convenient
expression for comparison with measurable quantities and for explicit
calculations avoiding the handling of large matrices. We consider the important
case of an isotropic two--qudit state and decompose it according to each basis.
Investigating the geometry of entanglement of special parameterized two--qubit
and two--qutrit states, in particular we calculate the Hilbert--Schmidt measure
of entanglement, we find that the Weyl operator basis is the optimal choice
since it is closely connected to the entanglement of the considered states.


title: On a complex differential Riccati equation

abstract:
  We consider a nonlinear partial differential equation for complex-valued
functions which is related to the two-dimensional stationary Schrodinger
equation and enjoys many properties similar to those of the ordinary
differential Riccati equation as, e.g., the famous Euler theorems, the Picard
theorem and others. Besides these generalizations of the classical
"one-dimensional" results we discuss new features of the considered equation
like, e.g., an analogue of the Cauchy integral theorem.


title:
Noether Symmetries and Conservations Laws For Non-critical Kohn-Laplace
  Equations on Three-Dimensional Heisenberg Group

abstract:
  We show which Lie point symmetries of non-critical semilinear Kohn-Laplace
equations on the Heisenberg group $H^1$ are Noether symmetries and we establish
their respectives conservations laws.


title: Triplet Josephson effect with magnetic feedback

abstract:
  We study AC Josephson effect in a superconductor-ferromagnet heterostructure
with a variable magnetic configuration. The system supports triplet proximity
correlations whose dynamics is coupled to the magnetic dynamics. This feedback
dramatically modifies the behavior of the junction. The current-phase relation
becomes double-periodic at both very low and high Josephson frequencies
$\omega_J$. At intermediate frequencies, the periodicity in $\omega_J t$ may be
lost.


title: Characterization of coherent impurity effects in solid state qubits

abstract:
  We propose a characterisation of the effects of bistable coherent impurities
in solid state qubits. We introduce an effective impurity description in terms
of a tunable spin-boson environment and solve the dynamics for the qubit
coherences. The dominant rate characterizing the asymptotic time limit is
identified and signatures of non-Gaussian behavior of the quantum impurity at
intermediate times are pointed out. An alternative perspective considering the
qubit as a measurement device for the spin-boson impurity is proposed.


title: Crystal Irradiation Stimulation of Enzyme Reactivity: An Explanation

abstract:
  In 1968, Sorin Comorosan first reported a phenomenon wherein irradiation of
the substrate of an enzyme reaction, in the crystalline state, for a specific
number of seconds could lead to an enhanced aqueous solution reaction rate for
the enzyme(up to 30%). Dependence on crystal irradiation time was found to be
oscillatory with a fixed period. The basis for this unusual phenomenon has
remained a mystery. Previously unreported experimental results are presented
which demonstrate, for the LDH / pyruvate reaction, that the identity of the
crystalline material irradiated is, largely, inconsequential. It is proposed
here that the irradiation procedure drives oscillatory reactions involving
atmospheric gases adsorbed on the crystals and that these photoproducts, or
related dark-reaction species, when dissolved, function as enzyme cofactors.


title:
Studies of clustering in the arrival directions of cosmic rays detected
  at the Pierre Auger Observatory above 10 EeV

abstract:
  If clustering of the arrival directions of ultra high energy cosmic rays is
discovered, this would provide important information about their origin,
composition, and the galactic and extragalactic magnetic fields. We present
here the analysis of the autocorrelation function of the data from the Pierre
Auger Observatory as a function of the angular scale and the energy threshold.
We compare our results with the signals found by previous experiments.


title:
On the Linearization of the Painleve' III-VI Equations and Reductions of
  the Three-Wave Resonant System

abstract:
  We extend similarity reductions of the coupled (2+1)-dimensional three-wave
resonant interaction system to its Lax pair. Thus we obtain new 3x3 matrix
Fuchs--Garnier pairs for the third and fifth Painleve' equations, together with
the previously known Fuchs--Garnier pair for the fourth and sixth Painleve'
equations. These Fuchs--Garnier pairs have an important feature: they are
linear with respect to the spectral parameter. Therefore we can apply the
Laplace transform to study these pairs. In this way we found reductions of all
pairs to the standard 2x2 matrix Fuchs--Garnier pairs obtained by M. Jimbo and
T. Miwa. As an application of the 3x3 matrix pairs, we found an integral
auto-transformation for the standard Fuchs--Garnier pair for the fifth
Painleve' equation. It generates an Okamoto-like B\"acklund transformation for
the fifth Painleve' equation. Another application is an integral transformation
relating two different 2x2 matrix Fuchs--Garnier pairs for the third Painleve'
equation.


title: MacWilliams Identity for Codes with the Rank Metric

abstract:
  The MacWilliams identity, which relates the weight distribution of a code to
the weight distribution of its dual code, is useful in determining the weight
distribution of codes. In this paper, we derive the MacWilliams identity for
linear codes with the rank metric, and our identity has a different form than
that by Delsarte. Using our MacWilliams identity, we also derive related
identities for rank metric codes. These identities parallel the binomial and
power moment identities derived for codes with the Hamming metric.


title:
Partial Inertial Manifolds for infinite-dimensional dynamical systems:
  Example for P.D.E.s with a state-dependent delay

abstract:
  We propose a new notion of Partial Inertial Manifold to study the long-time
asymptotic behavior of dissipative differential equations. As shown on an
example, such manifolds may exist in the cases when the classical Inertial
manifold does not exist (or not known to exist).


title:
Concentration of the Spectral Measure for Large Random Matrices with
  Stable Entries

abstract:
  We derive concentration inequalities for functions of the empirical measure
of large random matrices with infinitely divisible entries and, in particular,
stable ones. We also give concentration results for some other functionals of
these random matrices, such as the largest eigenvalue or the largest singular
value.


title: Protein structure prediction by an iterative search method

abstract:
  We demonstrate a new algorithm for finding protein conformations that
minimize a non-bonded energy function. The new algorithm, called the difference
map, seeks to find an atomic configuration that is simultaneously in two
constraint spaces. The first constraint space is the space of atomic
configurations that have a valid peptide geometry, while the second is the
space of configurations that have a non-bonded energy below a given target.
These two constraint spaces are used to define a deterministic dynamical
system, whose fixed points produce atomic configurations in the intersection of
the two constraint spaces. The rate at which the difference map produces low
energy protein conformations is compared with that of a contemporary search
algorithm, parallel tempering. The results indicate the difference map finds
low energy protein conformations at a significantly higher rate then parallel
tempering.


title:
FreeBSD Mandatory Access Control Usage for Implementing Enterprise
  Security Policies

abstract:
  FreeBSD was one of the first widely deployed free operating systems to
provide mandatory access control. It supports a number of classic MAC models.
This tutorial paper addresses exploiting this implementation to enforce typical
enterprise security policies of varying complexities.


title: IBM-1 description of the fission products $^{108,110,112}$Ru

abstract:
  IBM-1} calculations for the fission products $^{108,110,112}$Ru have been
carried out. The even-even isotopes of Ru can be described as transitional
nuclei situated between the U(5) (spherical vibrator) and SO(6)
($\gamma$-unstable rotor) symmetries of the Interacting Boson Model. At first,
a Hamiltonian with only one- and two-body terms has been used. Excitation
energies and $B$(E2) ratios of gamma transitions have been calculated. A
satisfactory agreement has been obtained, with the exception of the odd-even
staggering in the quasi-$\gamma$ bands of $^{110,112}$Ru. The observed pattern
is rather similar to the one for a rigid triaxial rotor. A calculation based on
a Hamiltonian with three-body terms was able to remove this discrepancy. The
relation between the IBM and the triaxial rotor model was also examined.


title:
Basis set convergence of post-CCSD contributions to molecular
  atomization energies

abstract:
  Basis set convergence of correlation effects on molecular atomization
energies beyond the CCSD (coupled cluster with singles and doubles)
approximation has been studied near the one-particle basis set limit.
Quasiperturbative connected triple excitations, (T), converge more rapidly than
$L^{-3}$ (where $L$ is the highest angular momentum represented in the basis
set), while higher-order connected triples, $T_3-(T)$, converge more slowly --
empirically, $\propto L^{-5/2}$. Quasiperturbative connected quadruple
excitations, (Q), converge smoothly as $\propto L^{-3}$ starting with the
cc-pVTZ basis set, while the cc-pVDZ basis set causes overshooting of the
contribution in highly polar systems. Higher-order connected quadruples display
only weak, but somewhat erratic, basis set dependence. Connected quintuple
excitations converge very rapidly with the basis set, to the point where even
an unpolarized double-zeta basis set yields useful numbers. In cases where
fully iterative CCSDTQ5 (coupled cluster up to connected quintuples)
calculations are not an option, CCSDTQ(5) (i.e., coupled cluster up to
connected quadruples plus a quasiperturbative connected quintuples correction)
cannot be relied upon in the presence of significant nondynamical correlation,
whereas CCSDTQ(5)$_\Lambda$ represents a viable alternative. Connected
quadruples corrections to the core-valence contribution are thermochemically
significant in some systems. [...] We conclude that ``$3\sigma\leq 1$ kJ/mol''
thermochemistry is feasible with current technology, but that the more
ambitious goal of $\pm$10 cm$^{-1}$ accuracy is illusory, at least for
atomization energies.


title: Statistics of football dynamics

abstract:
  We investigate the dynamics of football matches. Our goal is to characterize
statistically the temporal sequence of ball movements in this collective sport
game, searching for traits of complex behavior. Data were collected over a
variety of matches in South American, European and World championships
throughout 2005 and 2006. We show that the statistics of ball touches presents
power-law tails and can be described by $q$-gamma distributions. To explain
such behavior we propose a model that provides information on the
characteristics of football dynamics. Furthermore, we discuss the statistics of
duration of out-of-play intervals, not directly related to the previous
scenario.


title:
A generalized Petviashvili iteration method for scalar and vector
  Hamiltonian equations with arbitrary form of nonlinearity

abstract:
  The Petviashvili's iteration method has been known as a rapidly converging
numerical algorithm for obtaining fundamental solitary wave solutions of
stationary scalar nonlinear wave equations with power-law nonlinearity: \
$-Mu+u^p=0$, where $M$ is a positive definite self-adjoint operator and $p={\rm
const}$. In this paper, we propose a systematic generalization of this method
to both scalar and vector Hamiltonian equations with arbitrary form of
nonlinearity and potential functions. For scalar equations, our generalized
method requires only slightly more computational effort than the original
Petviashvili method.


title:
A Unique Determination of the Effective Potential in Terms of
  Renormalization Group Functions

abstract:
  The perturbative effective potential V in the massless $\lambda\phi^4$ model
with a global O(N) symmetry is uniquely determined to all orders by the
renormalization group functions alone when the Coleman-Weinberg renormalization
condition $\frac{d^4V}{d\phi^4}|_{\phi = \mu} = \lambda$ is used, where $\mu$
represents the renormalization scale. Systematic methods are developed to
express the n-loop effective potential in the Coleman-Weinberg scheme in terms
of the known n-loop minimal subtraction (MS) renormalization-group functions.
Moreover, it also proves possible to sum the leading- and
subsequent-to-leading-logarithm contributions to V. An essential element of
this analysis is a conversion of the renormalization group functions in the
Coleman-Weinberg scheme to the renormalization group functions in the MS
scheme. As an example, the explicit five-loop effective potential is obtained
from the known five-loop MS renormalization group functions and we explicitly
sum the leading logarithm (LL), next-to-leading (NLL), and further
subleading-logarithm contributions to V. Extensions of these results to
massless scalar QED are also presented. Because massless scalar QED has two
couplings, conversion of the RG functions from the MS scheme to the CW scheme
requires the use of multi-scale renormalization group methods.


title:
Extraspecial Two-Groups, Generalized Yang-Baxter Equations and Braiding
  Quantum Gates

abstract:
  In this paper we describe connections among extraspecial 2-groups, unitary
representations of the braid group and multi-qubit braiding quantum gates. We
first construct new representations of extraspecial 2-groups. Extending the
latter by the symmetric group, we construct new unitary braid representations,
which are solutions to generalized Yang-Baxter equations and use them to
realize new braiding quantum gates. These gates generate the GHZ
(Greenberger-Horne-Zeilinger) states, for an arbitrary (particularly an
\emph{odd}) number of qubits, from the product basis. We also discuss the
Yang-Baxterization of the new braid group representations, which describes
unitary evolution of the GHZ states. Our study suggests that through their
connection with braiding gates, extraspecial 2-groups and the GHZ states may
play an important role in quantum error correction and topological quantum
computing.


title: The Detailed Forms of the LMC Cepheid PL and PLC Relations

abstract:
  Possible deviations from linearity of the LMC Cepheid PL and PLC relations
are investigated. Two datasets are studied, respectively from the OGLE and
MACHO projects. A nonparametric test, based on linear regression residuals,
suggests that neither PL relation is linear. If colour dependence is allowed
for then the MACHO PL relation is found to deviate more significantly from the
linear, while the OGLE PL relation is consistent with linearity. These finding
are confirmed by fitting "Generalised Additive Models" (nonparametric
regression functions) to the two datasets. Colour dependence is shown to be
nonlinear in both datasets, distinctly so in the case of the MACHO Cepheids. It
is also shown that there is interaction between the period and colour functions
in the MACHO data.


title: A discrete mean value of the derivative of the Riemann zeta function

abstract:
  In this article we compute a discrete mean value of the derivative of the
Riemann zeta function. This mean value will be important for several
applications concerning the size of $\zeta'(\rho)$ where $\zeta(s)$ is the
Riemann zeta function and $\rho$ is a non-trivial zero of the Riemann zeta
function.


title:
Classical potential describes martensitic phase transformations between
  the $\alpha$, $\beta$ and $\omega$ titanium phases

abstract:
  A description of the martensitic transformations between the $\alpha$,
$\beta$ and $\omega$ phases of titanium that includes nucleation and growth
requires an accurate classical potential. Optimization of the parameters of a
modified embedded atom potential to a database of density-functional
calculations yields an accurate and transferable potential as verified by
comparison to experimental and density functional data for phonons, surface and
stacking fault energies and energy barriers for homogeneous martensitic
transformations. Molecular dynamics simulations map out the
pressure-temperature phase diagram of titanium. For this potential the
martensitic phase transformation between $\alpha$ and $\beta$ appears at
ambient pressure and 1200 K, between $\alpha$ and $\omega$ at ambient
conditions, between $\beta$ and $\omega$ at 1200 K and pressures above 8 GPa,
and the triple point occurs at 8GPa and 1200 K. Molecular dynamics explorations
of the dynamics of the martensitic $\alpha-\omega$ transformation show a
fast-moving interface with a low interfacial energy of 30 meV/\AA$^2$. The
potential is applicable to the study of defects and phase transformations of
Ti.


title: Extreme values of zeta prime rho

abstract:
  In this article we exhibit small and large values of $\zeta'(\rho)$ by
applying Soundararajan's resonance method. Our results assume the Riemann
hypothesis.


title:
Orbital liquid in ferromagnetic manganites: The orbital Hubbard model
  for $e_g$ electrons

abstract:
  We have analyzed the symmetry properties and the ground state of an orbital
Hubbard model with two orbital flavors, describing a partly filled
spin-polarized $e_g$ band on a cubic lattice, as in ferromagnetic manganites.
We demonstrate that the off-diagonal hopping responsible for transitions
between $x^2-y^2$ and $3z^2-r^2$ orbitals, and the absence of SU(2) invariance
in orbital space, have important implications. One finds that superexchange
contributes in all orbital ordered states, the Nagaoka theorem does not apply,
and the kinetic energy is much enhanced as compared with the spin case.
Therefore, orbital ordered states are harder to stabilize in the Hartree-Fock
approximation (HFA), and the onset of a uniform ferro-orbital polarization and
antiferro-orbital instability are similar to each other, unlike in spin case.
Next we formulate a cubic (gauge) invariant slave boson approach using the
orbitals with complex coefficients. In the mean-field approximation it leads to
the renormalization of the kinetic energy, and provides a reliable estimate for
the ground state energy of the disordered state. Using this approach one finds
that the HFA fails qualitatively in the regime of large Coulomb repulsion
$U\to\infty$ -- the orbital order is unstable, and instead a strongly
correlated orbital liquid with disordered orbitals is realized at any electron
filling.


title: VHE astrophysics: recent developments

abstract: We review the current status, and some open issues, of VHE astrophysics.


title:
The black hole in the throat - thermodynamics of strongly coupled
  cascading gauge theories

abstract:
  We numerically construct black hole solutions corresponding to the
deconfined, chirally symmetric phase of strongly coupled cascading gauge
theories at various temperatures. We compute the free energy as a function of
the temperature, and we show that it becomes positive below some critical
temperature, indicating the possibility of a first order phase transition at
which the theory deconfines and restores the chiral symmetry.


title: Higher Derivative Corrections, Dimensional Reduction and Ehlers Duality

abstract:
  Motivated by applications to black hole physics and duality, we study the
effect of higher derivative corrections on the dimensional reduction of
four-dimensional Einstein, Einstein Liouville and Einstein-Maxwell gravity to
one direction, as appropriate for stationary, spherically symmetric solutions.
We construct a field redefinition scheme such that the one-dimensional
Lagrangian is corrected only by powers of first derivatives of the fields,
eliminating spurious modes and providing a suitable starting point for
quantization. We show that the Ehlers symmetry, broken by the leading $R^2$
corrections in Einstein-Liouville gravity, can be restored by including
contributions of Taub-NUT instantons. Finally, we give a preliminary discussion
of the duality between higher-derivative F-term corrections on the vector and
hypermultiplet branches in N=2 supergravity in four dimensions.


title: Cracking the Supersolid

abstract:
  We prepresent an overview of the status of experiment and theory on the
supersolid state of matter.


title: The fundamental progroupoid of a general topos

abstract:
  It is well known that the category of covering projections (that is, locally
constant objects) of a locally connected topos is equivalent to the classifying
topos of a strict progroupoid (or, equivalently, a localic prodiscrete
groupoid), the \emph{fundamental progroupoid}, and that this progroupoid
represents first degree cohomology. In this paper we generalize these results
to an arbitrary topos. The fundamental progroupoid is now a localic
progroupoid, and can not be replaced by a localic groupoid. The classifying
topos in not any more a Galois topos. Not all locally constant objects can be
considered as covering projections. The key contribution of this paper is a
novel definition of covering projection for a general topos, which coincides
with the usual definition when the topos is locally connected. The results in
this paper were presented in a talk at the Category Theory Conference,
Vancouver July 2004.


title:
The GRB afterglow onset observed by REM: fireball Lorentz factor and
  afterglow fluence

abstract:
  We report observations of the early light curves of GRB 060418 and GRB
060607A, carried out with the pink robotic telescope REM. A clear peak is
detected for both events, which is interpreted as the onset of the afterglow,
that is the time at which the fireball starts decelerating. This detection
allows to directly measure the initial fireball Lorentz factor, which was found
to be Gamma_0 ~ 400 for both events, fully confirming the ultrarelativistic
nature of gamma-ray burst fireballs. Sampling the light curve before the peak
also allows to compute the bolometric fluence of the afterglow, which is 16% of
the prompt one in the case of GRB 060418.


title:
The Stokes phenomenon in the confluence of the hypergeometric equation
  using Riccati equation

abstract:
  In this paper we study the confluence of two regular singular points of the
hypergeometric equation into an irregular one. We study the consequence of the
divergence of solutions at the irregular singular point for the unfolded
system. Our study covers a full neighborhood of the origin in the confluence
parameter space. In particular, we show how the divergence of solutions at the
irregular singular point explains the presence of logarithmic terms in the
solutions at a regular singular point of the unfolded system. For this study,
we consider values of the confluence parameter taken in two sectors covering
the complex plane. In each sector, we study the monodromy of a first integral
of a Riccati system related to the hypergeometric equation. Then, on each
sector, we include the presence of logarithmic terms into a continuous
phenomenon and view a Stokes multiplier related to a 1-summable solution as the
limit of an obstruction that prevents a pair of eigenvectors of the monodromy
operators, one at each singular point, to coincide.


title: Functional Methods in the Generalized Dicke Model

abstract:
  The Dicke model describes an ensemble of N identical two-level atoms (qubits)
coupled to a single mode of a bosonic field. The fermion Dicke model should be
obtained by changing the atomic pseudo-spin operators by a linear combination
of Fermi operators. The generalized fermion Dicke model is defined introducing
different coupling constants between the single mode of the bosonic field and
the reservoir. In the thermodynamic limit, the fermion Dicke model can be
analized using the path integral approach with functional method. The system
exhibits a second order phase transition from normal to superrandiance at some
critical temperature with the presence of a condensate. We evaluate the
critical transition temperature and present the spectrum of the collective
bosonic excitations. There is quantum phantum critical behavior when the
coupling constants satisfy an especific condition. Two particular situations
are analyzed. First, we present the spectrum of the collective bosonic
excitations in the case using the rotating-wave approximation, recovering the
well know results. Second, the case only considering virtual processes. In the
last case, it is possible to have a superradiance phase when only virtual
processes are introduced in the interaction Hamiltonian. Here also appears a
quantum phase transition at some critical coupling, and for larger values for
the critical coupling, the system enter in this superradiant phase with a
Goldstone mode.


title: Galaxy-CMB Cross-Correlation as a Probe of Alternative Models of Gravity

abstract:
  Bekenstein's alternative to general relativity, TeVeS, reduces to Modified
Newtonian Dynamics (MOND) in the galactic limit. On cosmological scales, the
(potential well <-> overdensity) relationship is quite different than in
standard general relativity. Here we investigate the possibility of
cross-correlating galaxies with the cosmic microwave background (CMB) to probe
this relationship. At redshifts of order 2, the sign of the CMB-galaxy
correlation differs in TeVeS from that in general relativity. We show that this
effect is detectable and hence can serve as a powerful discriminator of these
two models of gravity.


title:
Coherence and phase synchronization: generalization to pairs of
  multivariate time series, and removal of zero-lag contributions

abstract:
  Coherence and phase synchronization between time series corresponding to
different spatial locations are usually interpreted as indicators of the
connectivity between locations. In neurophysiology, time series of electric
neuronal activity are essential for studying brain interconnectivity. Such
signals can either be invasively measured from depth electrodes, or computed
from very high time resolution, non-invasive, extracranial recordings of scalp
electric potential differences (EEG: electroencephalogram) and magnetic fields
(MEG: magnetoencephalogram) by means of a tomography such as sLORETA
(standardized low resolution brain electromagnetic tomography). There are two
problems in this case. First, in the usual situation of unknown cortical
geometry, the estimated signal at each brain location is a vector with three
components (i.e. a current density vector), which means that coherence and
phase synchronization must be generalized to pairs of multivariate time series.
Second, the inherent low spatial resolution of the EEG/MEG tomography
introduces artificially high zero-lag coherence and phase synchronization. In
this report, solutions to both problems are presented. Two additional
generalizations are briefly mentioned: (1) conditional coherence and phase
synchronization; and (2) non-stationary time-frequency analysis. Finally, a
non-parametric randomization method for connectivity significance testing is
outlined. The new connectivity measures proposed here can be applied to pairs
of univariate EEG/MEG signals, as is traditional in the published literature.
However, these calculations cannot be interpreted as connectivity, since it is
in general incorrect to associate an extracranial electrode or sensor to the
underlying cortex.


title: "Hidden" Seyfert 2 Galaxies in the Chandra Deep Field North

abstract:
  We have compared the X-ray--to--optical flux ratios (F_x/F_opt) of absorbed
active galactic nuclei (AGNs) in the Chandra Deep Field North (CDF-N) with
those of nearby, optically classified Seyfert 2 galaxies. The comparison
provides an opportunity to explore the extent to which the local population of
absorbed AGNs can account for the properties of the distant, spectroscopically
ambiguous sources that produce the hard X-ray background. Our nearby sample
consists of 38 objects that well represent the local Seyfert 2 luminosity
function. Integrated UBVRI photometry and broadband X-ray observations are
presented. Using these data, we have simulated the F_x/F_opt ratios that local
Seyfert 2s would exhibit if they were observed in the redshift range 0.2 < z <
1.3 as part of the CDF-N. In the simulations we account for the effects of
redshift on flux measurements in fixed observed-frame bands, and the way the
luminosity function of a given population is sampled in a flux-limited survey
like the CDF-N. Overall, we find excellent agreement between our simulations
and the observed distribution of F_x/F_opt ratios for absorbed AGNs in the
CDF-N. Our analysis has thus failed to reveal any physical differences between
the local population of Seyfert 2s and CDF-N sources with similar X-ray
properties. These results support the hypothesis that the nuclear emission
lines of many distant hard X-ray galaxies are hidden in ground-based spectra
due to a combination of observational effects: signal-to-noise ratio,
wavelength coverage, and dilution by host-galaxy light.


title: KLT relations from the Einstein-Hilbert Lagrangian

abstract:
  The Kawai-Lewellen-Tye (KLT) relations derived from string theory tell us
that perturbative gravity amplitudes are the "square" of the corresponding
amplitudes in gauge theory. Starting from the light-cone Lagrangian for pure
gravity we make these relations manifest off-shell, for three- and
four-graviton vertices, at the level of the action.


title: Lookback time bounds from energy conditions

abstract:
  In general relativity, the energy conditions are invoked to restrict general
energy-momentum tensors on physical grounds. We show that in the standard
Friedmann-Lemaitre-Robertson-Walker (FLRW) approach to cosmological modeling,
where the energy and matter components of the cosmic fluid are unknown, the
energy conditions provide model-independent bounds on the behavior of the
lookback time of cosmic sources as a function of the redshift for any value of
the spatial curvature. We also confront such bounds with a lookback time sample
which is built from the age estimates of 32 galaxies lying in the interval
$0.11 \lesssim z \lesssim 1.84$ and by assuming the total expanding age of the
Universe to be $13.7 \pm 0.2$ Gyr, as obtained from current cosmic microwave
background experiments. In agreement with previous results, we show that all
energy conditions seem to have been violated at some point of the recent past
of cosmic evolution.


title: Le travail collaboratif dans le cadre d'un projet architectural

abstract:
  The analysis of the practices and the tendencies of the users at the time of
the search for information on Internet makes it possible to highlight several
points. The search for information becomes powerful after knowledge of the
typology of the various systems of research. This typology supports the
adoption of a methodology of research which one can characterize by pull
systems, intelligent agents, etc. In addition, the importance of the structure
of the electronic document, correctly elaborated in advance, will support a
higher relevance ratio to find information. In our article, the problems turn
around the study of the behavior of the users in situation of search for
information, as well as the constitution of a pole of documentary resources
within a framework of an architectural project. It is noted that the evolution
of the documentary resources is related to information technologies.


title:
Superfluid and Pseudo-Goldstone Modes in Three Flavor Crystalline Color
  Superconductivity

abstract:
  We study the bosonic excitations in the favorite cubic three flavor
crystalline LOFF phases of QCD. We calculate in the Ginzburg-Landau
approximation the masses of the eight pseudo Nambu-Goldstone Bosons (NGB)
present in the low energy theory. We also compute the decay constants of the
massless NGB Goldstones associated to superfluidity as well as those of the
eight pseudo NGB. Differently from the corresponding situation in the
Color-Flavor-Locking phase, we find that meson condensation phases are not
expected in the present scenario.


title:
A Constant Spectral Index for Sagittarius A* During Infrared/X-ray
  Intensity Variations

abstract:
  We report the first time-series of broadband infrared (IR) color measurements
of Sgr A*, the variable emission source associated with the supermassive black
hole at the Galactic Center. Using the laser and natural guide star AO systems
on the Keck II telescope, we imaged Sgr A* in multiple near-infrared broadband
filters with a typical cycle time of ~3 min during 4 observing runs
(2005-2006), two of which were simultaneous with Chandra X-ray measurements. In
spite of the large range of dereddened flux densities for Sgr A* (2-30 mJy),
all of our near-IR measurements are consistent with a constant spectral index
of alpha = -0.6+-0.2. Furthermore, this value is consistent with the spectral
indices observed at X-ray wavelengths during nearly all outbursts; which is
consistent with the synchrotron self-Compton model for the production of the
X-ray emission. During the coordinated observations, one IR outburst occurs <36
min after a possibly associated X-ray outburst, while several similar IR
outbursts show no elevated X-ray emission. A variable X-ray to IR ratio and
constant infrared spectral index challenge the notion that the IR and X-ray
emission are connected to the same electrons. We, therefore, posit that the
population of electrons responsible for both the IR and X-ray emission are
generated by an acceleration mechanism that leaves the bulk of the electron
energy distribution responsible for the IR emission unchanged, but has a
variable high-energy cutoff. Occasionally a tail of electrons >1 GeV is
generated, and it is this high-energy tail that gives rise to the X-ray
outbursts. One possible explanation for this type of variation is from the
turbulence induced by a magnetorotational instability, in which the outer scale
length of the turbulence varies and changes the high-energy cutoff.


title:
Scaling and Enhanced Symmetry at the Quantum Critical Point of the
  Sub-Ohmic Bose-Fermi Kondo Model

abstract:
  We consider the finite temperature scaling properties of a Kondo-destroying
quantum critical point in the Ising-anisotropic Bose-Fermi Kondo model (BFKM).
A cluster-updating Monte Carlo approach is used, in order to reliably access a
wide temperature range. The scaling function for the two-point spin correlator
is found to have the form dictated by a boundary conformal field theory, even
though the underlying Hamiltonian lacks conformal invariance. Similar
conclusions are reached for all multi-point correlators of the spin-isotropic
BFKM in a dynamical large-N limit. Our results suggest that the quantum
critical local properties of the sub-ohmic BFKM are those of an underlying
boundary conformal field theory.


title: Surfaces with K^2<3\chi and finite fundamental group

abstract:
  In this paper we continue the study of algebraic fundamentale group of
minimal surfaces of general type S satisfying K_S^2<3\chi(S). We show that, if
K_S^2= 3\chi(S)-1 and the algebraic fundamental group of S has order 8, then S
is a Campedelli surface.
  In view of the results of math.AG/0512483 and math.AG/0605733, this implies
that the fundamental group of a surface with K^2<3\chi that has no irregular
etale cover has order at most 9, and if it has order 8 or 9, then S is a
Campedelli surface.
  To obtain this result we establish some classification results for minimal
surfaces of general type such that K^2=3p_g-5 and such that the canonical map
is a birational morphism. We also study rational surfaces with a Z_2^3-action.


title: Maximum stabilizer dimension for nonproduct states

abstract:
  Composite quantum states can be classified by how they behave under local
unitary transformations. Each quantum state has a stabilizer subgroup and a
corresponding Lie algebra, the structure of which is a local unitary invariant.
In this paper, we study the structure of the stabilizer subalgebra for n-qubit
pure states, and find its maximum dimension to be n-1 for nonproduct states of
three qubits and higher. The n-qubit Greenberger-Horne-Zeilinger state has a
stabilizer subalgebra that achieves the maximum possible dimension for pure
nonproduct states. The converse, however, is not true: we show examples of pure
4-qubit states that achieve the maximum nonproduct stabilizer dimension, but
have stabilizer subalgebra structures different from that of the n-qubit GHZ
state.


title:
Singular Fermi Surfaces I. General Power Counting and Higher Dimensional
  Cases

abstract:
  We prove regularity properties of the self-energy, to all orders in
perturbation theory, for systems with singular Fermi surfaces which contain Van
Hove points where the gradient of the dispersion relation vanishes. In this
paper, we show for spatial dimensions $d \ge 3$ that despite the Van Hove
singularity, the overlapping loop bounds we proved together with E. Trubowitz
for regular non--nested Fermi surfaces [J. Stat. Phys. 84 (1996) 1209] still
hold, provided that the Fermi surface satisfies a no-nesting condition. This
implies that for a fixed interacting Fermi surface, the self-energy is a
continuously differentiable function of frequency and momentum, so that the
quasiparticle weight and the Fermi velocity remain close to their values in the
noninteracting system to all orders in perturbation theory. In a companion
paper, we treat the more singular two-dimensional case.


title: The Search for the Missing Baryons at Low Redshift

abstract:
  At low redshift, only about one-tenth of the known baryons lie in galaxies or
the hot gas seen in galaxy clusters and groups. Models posit that these
"missing baryons" are in gaseous form in overdense filaments that connect the
much denser virialized groups and clusters. About 30% are cool (<1E5 K) and are
detected in Ly alpha absorption studies, but about half is predicted to lie in
the 1E5-1E7 K regime. Gas is detected in the 2-5E5 K range through OVI
absorption studies (7% of the baryons) and possibly near 1E5 K from broad Ly
absorption (20% of the baryons). Hotter gas (0.5-2E6 K) is detected at zero
redshift by OVII and OVIII K X-ray absorption, and the OVII line strengths seem
to correlate with the Galactic soft X-ray background, so it is probably
produced by Galactic Halo gas, rather than a Local Group medium. There are no
compelling detections of the intergalactic hot gas (0.5-10E6 K) either in
absorption or emission and these upper limits are consistent with theoretical
models. Claimed X-ray absorption lines are not confirmed, while most of the
claims of soft emission are attributable to artifacts of background subtraction
and field-flattening. The missing baryons should become detectable with
moderate improvements in instrumental sensitivity.


title: Singular Fermi Surfaces II. The Two--Dimensional Case

abstract:
  We consider many--fermion systems with singular Fermi surfaces, which contain
Van Hove points where the gradient of the band function $k \mapsto e(k)$
vanishes. In a previous paper, we have treated the case of spatial dimension $d
\ge 3$. In this paper, we focus on the more singular case $d=2$ and establish
properties of the fermionic self--energy to all orders in perturbation theory.
We show that there is an asymmetry between the spatial and frequency
derivatives of the self--energy. The derivative with respect to the Matsubara
frequency diverges at the Van Hove points, but, surprisingly, the self--energy
is $C^1$ in the spatial momentum to all orders in perturbation theory, provided
the Fermi surface is curved away from the Van Hove points. In a prototypical
example, the second spatial derivative behaves similarly to the first frequency
derivative. We discuss the physical significance of these findings.


title: B production at the LHC / QCD aspects

abstract:
  The LHC provides new opportunities to improve our understanding of the b
quark using high statistics data samples and the 14 TeV center-of-mass energy.
The prospects to measure the cross section for inclusive b production in events
containing jets and at least one muon are presented. Studies of detector
systematic effects and theoretical uncertainties are included. QCD aspects of
the beauty production are discussed.


title: How to measure efficiency?

abstract:
  In the context of applied game theory in networking environments, a number of
concepts have been proposed to measure both efficiency and optimality of
resource allocations, the most famous certainly being the price of anarchy and
the Jain index. Yet, very few have tried to question these measures and compare
them one to another, in a general framework, which is the aim of the present
article.


title: X-ray Luminosity Functions of Normal Galaxies in the GOODS

abstract:
  We present soft (0.5-2 keV) X-ray luminosity functions (XLFs) in the Great
Observatories Origins Deep Survey (GOODS) fields, derived for galaxies at
z~0.25 and 0.75. SED fitting was used to estimate photometric redshifts and
separate galaxy types, resulting in a sample of 40 early-type galaxies and 46
late-type galaxies. We estimate k-corrections for both the X-ray/optical and
X-ray/NIR flux ratios, which facilitates the separation of AGN from the
normal/starburst galaxies. We fit the XLFs with a power-law model using both
traditional and Markov-Chain Monte Carlo (MCMC) procedures. The XLFs differ
between z<0.5 and z>0.5, at >99% significance levels for early-type, late-type
and all (early and late-type) galaxies.We also fit Schechter and log-normal
models to the XLFs, fitting the low and high redshift XLFs for a given sample
simultaneously assuming only pure luminosity evolution. In the case of
log-normal fits, the results of MCMC fitting of the local FIR luminosity
function were used as priors for the faint and bright-end slopes (similar to
``fixing'' these parameters at the FIR values except here the FIR uncertainty
is included). The best-fit values of the change in log L* with redshift were
dlogL* = 0.23 +/- 0.16 dex (for early-type galaxies) and 0.34 +/- 0.12 dex (for
late-type galaxies), corresponding to (1+z)^1.6 and (1+z)^2.3. These results
were insensitive to whether the Schechter or log-normal function was adopted.


title: On existence of log minimal models

abstract:
  In this paper, we prove that the log minimal model program in dimension $d-1$
implies the existence of log minimal models for effective lc pairs (eg of
nonnegative Kodaira dimension) in dimension $d$. In fact, we prove that the
same conclusion follows from a weaker assumption, namely, the log minimal model
program with scaling in dimension $d-1$. This enables us to prove that
effective lc pairs in dimension five have log minimal models. We also give new
proofs of the existence of log minimal models for effective lc pairs in
dimension four and the Shokurov reduction theorem. Other applications appear in
a paper of Birkar-Paun.


title:
The beta function of gauge theories at two loops in differential
  renormalization

abstract:
  This PhD thesis is devoted to show that differential renormalization is a
simple and useful renormalization method that we can use when dealing with
gauge theories. In this work, it is shown how the one-loop results of
Constraint Differential Renormalization can be fruitfully applied when
renormalizing two-loop amplitudes. As an example of this procedure, the
two-loop beta functions of various relevant gauge theories are obtained (QED,
SuperQED, Yang-Mills and N=1 SuperYM) without making use of the Ward
identities, which are mandatory in the standard differential renormalization
procedure. Also, we study how to deal with expressions that have IR and UV
divergences, showing that both are renormalized with independent scales. This
result allow us to give new insight on the origin of the higher order
corrections to the beta function of the N=1 SuperYM theory, as in this case we
have both divergences due to the form of the gauge propagator. This is an
advantage over usual dimensional regularization methods, where both divergences
become mixed.


title: Birational geometry

abstract:
  This article contains the notes of a graduate course on birational geometry
focusing on the minimal model program. Topics covered include singularities,
vanishing, nonvanishing, cone and contraction, base point freeness, finite
generation, flips, termination, minimal models and Mori fibre spaces.


title:
Inverting geometric transitions: explicit Calabi-Yau metrics for the
  Maldacena-Nunez solutions

abstract:
  Explicit Calabi-Yau metrics are derived that are argued to map to the
Maldacena-Nu\~{n}ez AdS solutions of M-theory and IIB under geometric
transitions. In each case the metrics are singular where a H^2 K\"{a}hler
two-cycle degenerates but are otherwise smooth. They are derived as the most
general Calabi-Yau solutions of an ansatz for the supergravity description of
branes wrapped on K\"{a}hler two-cycles. The ansatz is inspired by re-writing
the AdS solutions, and the structure defined by half their Killing spinors, in
this form. The world-volume theories of fractional branes wrapped at the
singularities of these metrics are proposed as the duals of the AdS solutions.
The existence of supergravity solutions interpolating between the $AdS$ and
Calabi-Yau metrics is conjectured and their boundary conditions briefly
discussed.


title: Project to install roman pot detectors at 220 m in ATLAS

abstract:
  We give a short description of the project to install roman pot detectors at
220 m from the interaction point in ATLAS. This project is dedicated to hard
diffractive measurements at high luminosity.


title:
Soluble Models of Strongly Interacting Ultracold Gas Mixtures in Tight
  Waveguides

abstract:
  A generalized Fermi-Bose mapping method is used to determine the exact ground
states of several models of mixtures of strongly interacting ultracold gases in
tight waveguides, which are generalizations of the Tonks-Girardeau (TG) gas (1D
Bose gas with point hard cores) and fermionic Tonks-Girardeau (FTG) gas (1D
spin-aligned Fermi gas with infinitely strong zero-range attractions). We
detail the case of a Bose-Fermi mixture with TG boson-boson (BB) and
boson-fermion (BF) interactions. Exact results are given for density profiles
in a harmonic trap, single-particle density matrices, momentum distributions,
and density-density correlations. Since the ground state is highly degenerate,
we analyze the splitting of the ground manifold for large but finite BB and BF
repulsions.


title:
New QCD fits to HERA data and search for exclusive events at the
  Tevatron

abstract:
  We describe new QCD fits to diffractive proton structure functions measured
at HERA, and we use these parton densities to predict the shape of the dijet
mass fraction at the Tevatron and look for the existence of exclusive events in
the dijet channel.


title:
BFKL NLL phenomenology of forward jets at HERA and Mueller Navelet jets
  at the Tevatron and the LHC

abstract:
  We perform a BFKL-NLL analysis of forward jet production at HERA which leads
to a good description of data over the full kinematical domain. We also predict
the azimuthal angle dependence of Mueller-Navelet jet production at the
Tevatron and the LHC using the BFKL NLL formalism.


title: Necessary Conditions for Schur-Positivity

abstract:
  In recent years, there has been considerable interest in showing that certain
conditions on skew shapes A and B are sufficient for the difference s_A - s_B
of their skew Schur functions to be Schur-positive. We determine necessary
conditions for the difference to be Schur-positive. Our conditions are
motivated by those of Reiner, Shaw and van Willigenburg that are necessary for
s_A = s_B, and we deduce a strengthening of their result as a special case.


title:
Mass-to-light Ratio of Ly-alpha Emitters: Implications of Ly-alpha
  Surveys at Redshifts z=5.7, 6.5, 7, and 8.8

abstract:
  Using a simple method to interpret the luminosity function of Ly-alpha
emitters, we explore properties of Ly-alpha emitters from 5.7 < z < 8.8 with
various assumptions about metallicity and stellar mass spectra. We constrain a
mass-to-'observed' light ratio, M_h/L_band. For narrow-band surveys, L_band is
simply related to the intrinsic Ly-alpha luminosity with a survival fraction of
Ly-alpha photons, alpha_esc. The mass-to-'bolometric light', M_h/L_bol, can
also be deduced, once the metallicity and stellar mass spectrum are given. The
inferred M_h/L_bol is more sensitive to metallicity than to the mass spectrum.
We find the following constraints on a mass-to-light ratio of Ly-alpha emitters
from 5.7 < z < 7: (M_h/L_bol)(alpha_{esc}epsilon^{1/gamma})^{-1}=21-38, 14-26,
and 9-17 for Z=0, 1/50, and 1 Z_sun, respectively, where epsilon is the 'duty
cycle' of Ly-alpha emitters, and gamma ~ 2 is a local slope of the cumulative
luminosity function. Only weak lower limits are obtained for z=8.8. Therefore,
Ly-alpha emitters are consistent with either starburst galaxies M_h/L_bol ~
0.1-1 with a smaller Ly-alpha survival fraction, alpha_{esc}epsilon^{1/gamma}
~0.01-0.05, or normal populations (M_h/L_bol ~ 10) if a good fraction of
Ly-alpha photons survived, alpha_{esc}epsilon^{1/gamma} ~ 0.5-1. We find no
evidence for the end of reionization in the luminosity functions of Ly-alpha
emitters discovered in the current Ly-alpha surveys, including recent discovery
of one Ly-alpha emitter at z=7. The data are consistent with no evolution of
intrinsic properties of Ly-alpha emitters or neutral fraction in the
intergalactic medium up to z=7. No detection of sources at z=8.8 does not yield
a significant constraint yet. We also show that the lack of detection at z=8.8
does not rule out the high-z galaxies being the origin of the excess NIRB.


title:
Notes on Quantum Field Theory in Curved Spacetime: Problems Relating to
  the Concept of Particles and Hamiltonian Formalism

abstract:
  The aim of these notes is to elucidate some aspects of quantum field theory
in curved spacetime, especially those relating to the notion of particles. A
selection of issues relevant to wave-particle duality is given. The case of a
generic curved spacetime is outlined. A Hamiltonian formulation of quantum
field theory in curved spacetime is elaborated for a preferred reference frame
with a separated space metric (a static spacetime and a reductive synchronous
reference frame). Applications: (1) Black hole. (2) The universe; the
cosmological redshift is obtained in the context of quantum field theory.


title: Electronic stopping power in insulators from first principles

abstract:
  Using time-dependent density-functional theory we calculate from first
principles the rate of energy transfer from a moving proton or antiproton to
the electrons of an insulating material, LiF. The behavior of the electronic
stopping power versus projectile velocity displays an effective threshold
velocity of ~0.2 a.u. for the proton, consistent with recent experimental
observations, and also for the antiproton. The calculated proton/antiproton
stopping-power ratio is ~2.4 at velocities slightly above the threshold (v~0.4
a.u.), as compared to the experimental value of 2.1. The projectile energy loss
mechanism is observed to be stationary and extremely local.


title:
HD 114839 - An Am star showing both delta Scuti and gamma Dor pulsations
  discovered through MOST photometry

abstract:
  Using MOST (Microvariability and Oscillations of STars) satellite guide star
photometry, we have discovered a metallic A star showing hybrid p- and g-mode
pulsations. HD 114839 was observed nearly continuously for 10 days in March,
2005. We identify frequencies in three groups: the first centered near 2
cycles/day, in the gamma Dor pulsation range, and two others near 8 and 20,
both in the delta Scuti range. This is only the fourth known such hybrid
pulsator, including another MOST discovery (Rowe et al. 2006, this issue).


title:
The von Neumann entropy asymptotics in multidimensional fermionic
  systems

abstract:
  We study the von Neumann entropy asymptotics of pure translation-invariant
quasi-free states of d-dimensional fermionic systems. It is shown that the
entropic area law is violated by all these states: apart from the trivial
cases, the entropy of a cubic subsystem with edge length L cannot grow slower
than L^{d-1}ln L. As for the upper bound of the entropy asymptotics, the
zero-entropy-density property of these pure states is the only limit: it is
proven that arbitrary fast sub-L^d entropy growth is achievable.

categories: math-ph cond-mat.stat-mech math.MP quant-ph


title:
On the asymptotic behavior of Faber polynomials for domains with
  piecewise analytic boundary

abstract:
  For a function g(w) analytic and univalent in {w:1<|w|<\infty} with a simple
pole at \infty and a continuous extension to {w:|w|\geq 1}, we consider the
Faber polynomials F_n(z), n=0,1,2,..., associated to g(w) via their generating
function g'(w)/(g(w)-z)=\sum_{n=0}^\infty F_n(z)w^{-(n+1)}. Assuming that g(w)
maps the unit circle T onto a piecewise analytic curve L whose exterior domain
has no outward-pointing cusps, and under an additional assumption concerning
the "Lehman expansion" of g(w) about those points of T mapped onto corners of
L, we obtain asymptotic formulas for F_n(z) that yield fine results on the
location, limiting distribution and accumulation points of the zeros of the
Faber polynomials. The asymptotic formulas are shown to hold uniformly and the
exact rate of decay of the error terms involved is provided.


title:
Generalised knot groups distinguish the square and granny knots (with an
  appendix by David Savitt)

abstract:
  Given a knot K we may construct a group G_n(K) from the fundamental group of
K by adjoining an nth root of the meridian that commutes with the corresponding
longitude. These "generalised knot groups" were introduced independently by
Wada and Kelly, and contain the fundamental group as a subgroup. The square
knot SK and the granny knot GK are a well known example of a pair of distinct
knots with isomorphic fundamental groups. We show that G_n(SK) and G_n(GK) are
non-isomorphic for all n>1. This confirms a conjecture of Lin and Nelson, and
shows that the isomorphism type of G_n(K), n>1, carries more information about
K than the isomorphism type of the fundamental group. An appendix by David
Savitt contains some results on representations of the trefoil group in
PSL(2,p) that are needed for the proof.


title:
Simultaneous packing and covering in the two-dimensional Euclidean plane
  II

abstract:
  This paper determines the optimal upper bound for the simultaneous packing
and covering constants of the two-dimensional centrally symmetric convex
domains. It solved a problem opening for more than thirty years.


title:
The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. IV. Lupus
  Observed with MIPS

abstract:
  We present maps of 7.78 square degrees of the Lupus molecular cloud complex
at 24, 70, and $160\:\mu$m. They were made with the Spitzer Space Telescope's
Multiband Imaging Photometer for Spitzer (MIPS) instrument as part of the
Spitzer Legacy Program, ``From Molecular Cores to Planet-Forming Disks'' (c2d).
The maps cover three separate regions in Lupus, denoted I, III, and IV. We
discuss the c2d pipeline and how our data processing differs from it. We
compare source counts in the three regions with two other data sets and
predicted star counts from the Wainscoat model. This comparison shows the
contribution from background galaxies in Lupus I. We also create two color
magnitude diagrams using the 2MASS and MIPS data. From these results, we can
identify background galaxies and distinguish them from probable young stellar
objects. The sources in our catalogs are classified based on their spectral
energy distribution (SED) from 2MASS and Spitzer wavelengths to create a sample
of young stellar object candidates. From 2MASS data, we create extinction maps
for each region and note a strong corresponence between the extinction and the
$160\:\mu$m emission. The masses we derived in each Lupus cloud from our
extinction maps are compared to masses estimated from $^{13}$CO and C$^{18}$O
and found to be similar to our extinction masses in some regions, but
significantly different in others. Finally, based on our color-magnitude
diagrams, we selected 12 of our reddest candidate young stellar objects for
individual discussion. Five of the 12 appear to be newly-discovered YSOs.


title:
A sufficient condition for a number to be the order of a nonsingular
  derivation of a Lie algebra

abstract:
  A study of the set N_p of positive integers which occur as orders of
nonsingular derivations of finite-dimensional non-nilpotent Lie algebras of
characteristic p>0 was initiated by Shalev and continued by the present author.
The main goal of this paper is to show the abundance of elements of N_p. Our
main result shows that any divisor n of q-1, where q is a power of p, such that
$n\ge (p-1)^{1/p} (q-1)^{1-1/(2p)}$, belongs to N_p. This extends its special
case for p=2 which was proved in a previous paper by a different method.


title:
Direct determination of the epicycle frequency in the galactic disk, and
  the derived rotation velocity V0

abstract:
  We present a method which allows a direct measurement of the epicycle
frequency $\kappa$ in the galactic disk, using the large database on open
clusters completed by our group. The observed velocity vector (amplitude and
direction) of the clusters in the galactic plane is derived from the catalog
data. In the epicycle approximation, this velocity is the sum of the circular
velocity, described by the galactic rotation curve, and of a residual velocity,
which has a direction that rotates with the frequency $\kappa$. If for some
reason the clusters are formed with non-random initial perturbation velocity
direction (measured for instance with respect to the direction of circular
rotation), then a plot of the orientation angle of the residual velocity as a
function of age reveals the epicycle frequency. The data analysis confirms that
this is the case; due to the non-random initial velocities, it is possible to
measure $\kappa$ for different galactic radii. Our analysis considers that the
effect of the arms on the stellar orbits is small (the Galactic potential is
mainly axis-symmetric); in this sense our results do not depend on any specific
model of the spiral structure, like the existence of a given number of spiral
arms, or on a particular choice of the radius of corotation. The values of
$\kappa$ provide constraints on the rotation velocity of the disk and on its
minimum beyond the solar radius; in particular, $V_0$ is found to be 226 $\pm$
15 kms$^{-1}$ even if the short scale (R$_0$ = 7.5 kpc) of the galaxy is
adopted. The mesured $\kappa$ at the solar radius is 42$\pm$4
kms$^{-1}$kpc$^{-1}$.


title: Shell model study of neutron rich oxygen isotopes

abstract:
  Shell model calculations for low lying energy states of neutron rich oxygen
isotopes 19O, 20O, 21O, 22O, 23O, 24O, 25O, 26O have been performed using
OXBASH code. The configuration space consists of 0d5/2, 1s1/2, 0d3/2 orbital
for neutrons outside the 16O core. Different interactions namely, Wildenthal,
Preedom-Wildenthal, Wildenthal-Mcgrory and renormalized Kuo and Brown, which
are either empirical or realistic in nature have been used in the calculation,
The calculated energy spectrum are in good agreement with the experimental data
wherever available for the empirical interactions and the correct ordering of
levels is reproduced. The levels obtained from realistic interactions, though
have a small rms deviation, do not reproduce the correct ordering in some of
the cases. In the case of 21O, realistic interactions predict a much too
compressed 1/2+ state at energy 0.157 MeV compared to the experimental value of
1.218 MeV. For even isotopes the variation of the energy of the first 2+exited
state has been studied as a function of neutron number N. A sharp rise in the
value is observed at N=16 for both empirical and realistic interactions and
only at N=14 for empirical interactions. Significantly higher energy of first
2+ exited state compared to the value in the neighboring even-even nuclei is
considered as a signature for magic nuclei at N=14 and N=16.