title:
Fermion Masses and Mixings from Dihedral Flavor Symmetries with
  Preserved Subgroups

abstract:
  We perform a systematic study of dihedral groups used as flavor symmetry. The
key feature here is the fact that we do not allow the dihedral groups to be
broken in an arbitrary way, but in all cases some
  (non-trivial) subgroup has to be preserved. In this way we arrive at only
five possible (Dirac) mass matrix structures which can arise, if we require
that the matrix has to have a non-vanishing determinant and that at least two
of the three generations of left-handed (conjugate) fermions are placed into an
irreducible two-dimensional representation of the flavor group. We show that
there is no difference between the mass matrix structures for single- and
double-valued dihedral groups. Furthermore, we comment on possible forms of
Majorana mass matrices. As a first application we find a way to express the
Cabibbo angle, i.e. the CKM matrix element |V_{us}|, in terms of group theory
quantities only, the group index n, the representation index j and the index
m_{u,d} of the different preserved subgroups in the up and down quark sector:
|V_{us}|=|cos(pi(m_{u}-m_{d})j/n)| which is |cos(3 pi/7)| = 0.2225 for n=7,
j=1, m_{u}=3 and m_{d}=0. We prove that two successful models which lead to
maximal atmospheric mixing and vanishing theta_{13} in the lepton sector are
based on the fact that the flavor symmetry is broken in the charged lepton,
Dirac neutrino and Majorana neutrino sector down to different preserved
subgroups whose mismatch results in the prediction of these mixing angles. This
also demonstrates the power of preserved subgroups in connection with the
prediction of mixing angles in the quark as well as in the lepton sector.


title: Search for photospheric footpoints of quiet Sun transition region loops

abstract:
  CONTEXT:The footpoints of quiet Sun Transition Region (TR) loops do not seem
to coincide with the photospheric magnetic structures appearing in traditional
low-sensitivity magnetograms.
  AIMS: To look for the so-far unidentified photospheric footpoints of TR loops
using G-band bright points (BPs) as proxies for photospheric magnetic field
concentrations.
  METHODS: Comparison of TR measurements with SoHO/SUMER and photospheric
magnetic field observations obtained with the Dutch Open Telescope.
  RESULTS: Photospheric BPs are associated with bright TR structures, but they
seem to avoid the brightest parts of the structure. BPs appear in regions that
are globally redshifted, but they avoid extreme velocities. TR explosive events
are not clearly associated with BPs.
  CONCLUSIONS: The observations are not inconsistent with the BPs being
footpoints of TR loops, although we have not succeeded to uniquely identify
particular BPs with specific TR loops.


title: An Auslander-type result for Gorenstein-projective modules

abstract:
  An artin algebra $A$ is said to be CM-finite if there are only finitely many,
up to isomorphisms, indecomposable finitely generated Gorenstein-projective
$A$-modules. We prove that for a Gorenstein artin algebra, it is CM-finite if
and only if every its Gorenstein-projective module is a direct sum of finitely
generated Gorenstein-projective modules. This is an analogue of Auslander's
theorem on algebras of finite representation type (\cite{A,A1}).


title:
L-algebras, triplicial-algebras, within an equivalence of categories
  motivated by graphs

abstract:
  In a previous work, we gave a coalgebraic framework of directed graphs
equipped with weights (or probability vectors) in terms of (Markov)
L-coalgebras. They are K-vector spaces equipped with two co-operations,
\Delta_M, \tilde{\Delta}_M verifying,
  (\tilde{\Delta}_M \otimes id)\Delta_M =(id \otimes \Delta_M)\tilde{\Delta}_M.
  In this paper, we study the category of L-algebras (dual of L-coalgebras),
prove that the free L-algebra on one generator is constructed over rooted
planar symmetric ternary trees with odd numbers of nodes and the L-operad is
Koszul. We then introduce triplicial-algebras: vector spaces equipped with
three associative operations verifying three entanglement relations. The free
triplicial-algebra is computed and turns out to be related to even trees. Via a
general structure theorem (\`a la Cartier-Milnor-Moore), we obtain that the
category of L-algebras is equivalent to a much more structured category called
connected coassociative triplicial-bialgebras (coproduct linked to operations
via infinitesimal relations), that is the triple of operads (As, Trip, L) is
good. Bidirected graphs, related to NAP-algebras, are briefly evoked and
postponed to another paper.


title:
First Stars VIII -- Enrichment of the neutron-capture elements in the
  early Galaxy

abstract:
  Our aim is to measure accurate, homogeneous neutron-capture element
abundances for the sample of 32 EMP giant stars studied earlier in this series,
including 22 stars with [Fe/H] $< -$3.0. Based on high-resolution, high S/N
spectra from the ESO VLT/UVES, 1D, LTE model atmospheres, and synthetic
spectrum fits, we determine abundances or upper limits for the 16 elements Sr,
Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, and Yb in all stars. As
found earlier, [Sr/Fe], [Y/Fe], [Zr/Fe] and [Ba/Fe] are below Solar in the EMP
stars, with very large scatter. However, we find a tight anti-correlation of
[Sr/Ba], [Y/Ba], and [Zr/Ba] with [Ba/H] for $-4.5 <$ [Ba/H] $< -2.5$, also
when subtracting the contribution of the main $r$-process as measured by
[Ba/H]. The huge, well-characterised scatter of the [n-capture/Fe] ratios in
our EMP stars is in stark contrast to the negligible dispersion in the
[$\alpha$/Fe] and [Fe-peak/Fe] ratios for the same stars found in Paper V.
These results demonstrate that a second (``weak'' or LEPP) $r$-process
dominates the production of the lighter neutron-capture elements for [Ba/H] $<
-2.5$. The combination of very consistent [$\alpha$/Fe] and erratic
[n-capture/Fe] ratios indicates that inhomogeneous models for the early
evolution of the halo are needed. Our accurate data provide strong constraints
on future models of the production and mixing of the heavy elements in the
early Galaxy.


title:
The Evolution of AGN Host Galaxies: From Blue to Red and the Influence
  of Large-Scale Structures

abstract:
  We present an analysis of 109 moderate-luminosity (41.9 < Log L{0.5-8.0 keV}
< 43.7) AGN in the Extended Chandra Deep Field-South survey, which is drawn
from 5,549 galaxies from the COMBO-17 and GEMS surveys having 0.4 < z < 1.1.
These obscured or optically-weak AGN facilitate the study of their host
galaxies since the AGN provide an insubstantial amount of contamination to the
galaxy light. We find that the color distribution of AGN host galaxies is
highly dependent upon (1) the strong color-evolution of luminous (M_V < -20.7)
galaxies, and (2) the influence of ~10 Mpc scale structures. When excluding
galaxies within the redshift range 0.63 < z < 0.76, a regime dominated by
sources in large-scale structures at z=0.67 and z=0.73, we observe a bimodality
in the host galaxy colors. Galaxies hosting AGN at z > 0.8 preferentially have
bluer (rest-frame U-V < 0.7) colors than their z <~ 0.6 counterparts (many of
which fall along the red sequence). The fraction of galaxies hosting AGN peaks
in the ``green valley'' (0.5 < U-V < 1.0); this is primarily due to enhanced
AGN activity in the redshift interval 0.63 < z < 0.76. The AGN fraction in this
redshift and color interval is 12.8% (compared to its `field' value of 7.8%)
and reaches a maximum of 14.8% at U-V~0.8. We further find that blue,
bulge-dominated (Sersic index n>2.5) galaxies have the highest fraction of AGN
(21%) in our sample. We explore the scenario that the evolution of AGN hosts is
driven by galaxy mergers and illustrate that an accurate assessment requires a
larger area survey since only three hosts may be undergoing a merger with
timescales <1 Gyr following a starburst phase.


title:
Dynamics of Bloch Electrons in Time Dependent External Electric Fields:
  Bounds for Interband Transitions

abstract:
  Using adiabatic expansions formalism, upper bounds for interband transitions
for Bloch electrons in slowly varying in time electric fields are obtained.
These bounds imply the validity of one-band approximation on long time scales.


title: Concerning Hidden Momentum

abstract:
  The fact that the author of an excellent textbook on electromagnetism could
be duped by "hidden momentum" vividly illustrates the problematic nature of its
use.


title:
Large-angle production of charged pions by 3 GeV/c - 12.9 GeV/c protons
  on beryllium, aluminium and lead targets

abstract:
  Measurements of the double-differential $\pi^{\pm}$ production cross-section
in the range of momentum $100 \MeVc \leq p < 800 \MeVc$ and angle $0.35 \rad
\leq \theta < 2.15 \rad$ in proton--beryllium, proton--aluminium and
proton--lead collisions are presented. The data were taken with the HARP
detector in the T9 beam line of the CERN PS. The pions were produced by proton
beams in a momentum range from 3 \GeVc to 12.9 \GeVc hitting a target with a
thickness of 5% of a nuclear interaction length. The tracking and
identification of the produced particles was performed using a small-radius
cylindrical time projection chamber (TPC) placed inside a solenoidal magnet.
Incident particles were identified by an elaborate system of beam detectors.
Results are obtained for the double-differential cross-sections at six incident
proton beam momenta (3 \GeVc, 5 \GeVc, 8 \GeVc, 8.9 \GeVc (Be only), 12 \GeVc
and 12.9 \GeVc (Al only)) and compared to previously available data.


title: Did one observe couplings of right-handed quarks to W ?

abstract:
  I consider non standard EW couplings of light right-handed quarks to W and Z
suggested in a systematic non decoupling bottom-up low-energy effective theory
approach to possible extensions of the Standard Model. New experimental tests
in K^L_{mu3} decays based on recent measurements and scalar form factor
analysis are discussed. A successful NLO fit to the standard set of Z-pole and
other NC data is presented as well.


title: Superconducting charge qubits from a microscopic many-body perspective

abstract:
  The quantised Josephson junction equation that underpins the behaviour of
charge qubits and other tunnel devices is usually derived through cannonical
quantisation of the classical macroscopic Josephson relations. However, this
approach may neglect effects due to the fact that the charge qubit consists of
a superconducting island of finite size connected to a large superconductor.
  We show that the well known quantised Josephson equation can be derived
directly and simply from a microscopic many-body Hamiltonian. By choosing the
appropriate strong coupling limit we produce a highly simplified Hamiltonian
that nevertheless allows us to go beyond the mean field limit and predict
further finite-size terms in addition to the basic equation.


title: Fast Algorithm and Implementation of Dissimilarity Self-Organizing Maps

abstract:
  In many real world applications, data cannot be accurately represented by
vectors. In those situations, one possible solution is to rely on dissimilarity
measures that enable sensible comparison between observations. Kohonen's
Self-Organizing Map (SOM) has been adapted to data described only through their
dissimilarity matrix. This algorithm provides both non linear projection and
clustering of non vector data. Unfortunately, the algorithm suffers from a high
cost that makes it quite difficult to use with voluminous data sets. In this
paper, we propose a new algorithm that provides an important reduction of the
theoretical cost of the dissimilarity SOM without changing its outcome (the
results are exactly the same as the ones obtained with the original algorithm).
Moreover, we introduce implementation methods that result in very short running
times. Improvements deduced from the theoretical cost model are validated on
simulated and real world data (a word list clustering problem). We also
demonstrate that the proposed implementation methods reduce by a factor up to 3
the running time of the fast algorithm over a standard implementation.


title: Can High Frequency Acoustic Waves Heat the Quiet Sun Chromosphere?

abstract:
  We use Hinode/SOT Ca II H-line and blue continuum broadband observations to
study the presence and power of high frequency acoustic waves at high spatial
resolution. We find that there is no dominant power at small spatial scales;
the integrated power using the full resolution of Hinode (0.05'' pixels, 0.16''
resolution) is larger than the power in the data degraded to 0.5'' pixels
(TRACE pixel size) by only a factor of 1.2. At 20 mHz the ratio is 1.6.
Combining this result with the estimates of the acoustic flux based on TRACE
data of Fossum & Carlsson (2006), we conclude that the total energy flux in
acoustic waves of frequency 5-40 mHz entering the internetwork chromosphere of
the quiet Sun is less than 800 W m$^{-2}$, inadequate to balance the radiative
losses in a static chromosphere by a factor of five.


title: Quantum Ratchets for Quantum Communication with Optical Superlattices

abstract:
  We propose to use a quantum ratchet to transport quantum information in a
chain of atoms trapped in an optical superlattice. The quantum ratchet is
created by a continuous modulation of the optical superlattice which is
periodic in time and in space. Though there is zero average force acting on the
atoms, we show that indeed the ratchet effect permits atoms on even and odd
sites to move along opposite directions. By loading the optical lattice with
two-level bosonic atoms, this scheme permits to perfectly transport a qubit or
entangled state imprinted in one or more atoms to any desired position in the
lattice. From the quantum computation point of view, the transport is achieved
by a smooth concatenation of perfect swap gates. We analyze setups with
noninteracting and interacting particles and in the latter case we use the
tools of optimal control to design optimal modulations. We also discuss the
feasibility of this method in current experiments.


title:
Large-angle production of charged pions by 3 GeV/c - 12 GeV/c protons on
  carbon, copper and tin targets

abstract:
  A measurement of the double-differential $\pi^{\pm}$ production cross-section
in proton--carbon, proton--copper and proton--tin collisions in the range of
pion momentum $100 \MeVc \leq p < 800 \MeVc$ and angle $0.35 \rad \le \theta
<2.15 \rad$ is presented. The data were taken with the HARP detector in the T9
beam line of the CERN PS. The pions were produced by proton beams in a momentum
range from 3 \GeVc to 12 \GeVc hitting a target with a thickness of 5% of a
nuclear interaction length. The tracking and identification of the produced
particles was done using a small-radius cylindrical time projection chamber
(TPC) placed in a solenoidal magnet. An elaborate system of detectors in the
beam line ensured the identification of the incident particles. Results are
shown for the double-differential cross-sections at four incident proton beam
momenta (3 \GeVc, 5 \GeVc, 8 \GeVc and 12 \GeVc).


title: Dynamical Quantum Geometry (DQG Programme)

abstract:
  In this brief note (written as a lengthy letter), we describe the
construction of a representation for the Weyl-algebra underlying Loop Quantum
Geometry constructed from a diffeomorphism variant state, which corresponds to
a ''condensate'' of Loop Quantum Geometry, resembling a static spatial
geometry. We present the kinematical GNS-representation and the gauge- and
diffeomorphism invariant Hilbert space representation and show that the
expectation values of the geometric operators take essentialy classical values
plus quantum corrections, which is similar to a ''local condensate'' of quantum
geometry. We describe the idea for the construction of a scale dependent
asymptotic map into a family of scale dependent lattice gauge theories, where
scale separates the essential geometry and a low energy effective theory, which
is described as degrees of freedom in the lattice gauge theory. If this idea
can be implemented then it is likely to turn out that this Hilbert space
contains in addition to gravity also gauge coupled ''extra degrees of
freedom'', which may not be dynamically irrelevant.


title: Iwasawa decompositions of split Kac-Moody groups

abstract:
  We characterize all fields F for which a group with an F-locally split root
group datum admits an Iwasawa decomposition. This class of groups in particular
includes the split semisimple algebraic groups and the split Kac-Moody groups.


title: Eigenvalue bounds for polynomial central potentials in d dimensions

abstract:
  If a single particle obeys non-relativistic QM in R^d and has the Hamiltonian
H = - Delta + f(r), where f(r)=sum_{i = 1}^{k}a_ir^{q_i}, 2\leq q_i < q_{i+1},
a_i \geq 0$, then the eigenvalues E = E_{n\ell}^{(d)}(\lambda) are given
approximately by the semi-classical expression E = \min_{r > 0}[\frac{1}{r^2} +
\sum_{i = 1}^{k}a_i(P_ir)^{q_i}]. It is proved that this formula yields a lower
bound if P_i = P_{n\ell}^{(d)}(q_1), an upper bound if $P_i =
P_{n\ell}^{(d)}(q_k) and a general approximation formula if P_i =
P_{n\ell}^{(d)}(q_i). For the quantum anharmonic oscillator f(r)=r^2+\lambda
r^{2m},m=2,3,... in d dimension, for example, E = E_{n\ell}^{(d)}(\lambda) is
determined by the algebraic expression
  \lambda={1\over \beta}({2\alpha(m-1)\over mE-\delta})^m({4\alpha \over
(mE-\delta)}-{E\over (m-1)}) where \delta={\sqrt{E^2m^2-4\alpha(m^2-1)}} and
\alpha, \beta are constants. An improved lower bound to the lowest eigenvalue
in each angular-momentum subspace is also provided. A comparison with the
recent results of Bhattacharya et al (Phys. Lett. A, 244 (1998) 9) and Dasgupta
et al (J. Phys. A: Math. Theor., 40 (2007) 773) is discussed.


title: Ergodic behaviour of "signed voter models"

abstract:
  We consider some questions raised by the recent paper of Gantert, L\"owe and
Steif (2005) concerning ``signed'' voter models on locally finite graphs. These
are voter model like processes with the difference that the edges are
considered to be either positive or negative. If an edge between a site $x$ and
a site $y$ is negative (respectively positive) the site $y$ will contribute
towards the flip rate of $x$ if and only if the two current spin values are
equal (respectively opposed).


title:
On geodesic homotopies of controlled width and conjugacies in isometry
  groups

abstract:
  We give an analytical proof of the Poincare-type inequalities for widths of
geodesic homotopies between equivariant maps valued in Hadamard metric spaces.
As an application we obtain a linear bound for the length of an element
conjugating two finite lists in a group acting on an Hadamard space.


title:
Constraints on sigma_8 from galaxy clustering in N-body simulations and
  semi-analytic models

abstract:
  We generate mock galaxy catalogues for a grid of different cosmologies, using
rescaled N-body simulations in tandem with a semi-analytic model run using
consistent parameters. Because we predict the galaxy bias, rather than fitting
it as a nuisance parameter, we obtain an almost pure constraint on sigma_8 by
comparing the projected two-point correlation function we obtain to that from
the SDSS. A systematic error arises because different semi-analytic modelling
assumptions allow us to fit the r-band luminosity function equally well.
Combining our estimate of the error from this source with the statistical
error, we find sigma_8=0.97 +/- 0.06. We obtain consistent results if we use
galaxy samples with a different magnitude threshold, or if we select galaxies
by b_J-band rather than r-band luminosity and compare to data from the 2dFGRS.
Our estimate for sigma_8 is higher than that obtained for other analyses of
galaxy data alone, and we attempt to find the source of this difference. We
note that in any case, galaxy clustering data provide a very stringent
constraint on galaxy formation models.


title: Possible solution of the J/psi production puzzle

abstract:
  We argue that the s-channel cut contribution to J/psi hadroproduction can be
significantly larger than the usual cut contribution of the color-singlet
mechanism, which is known to underestimate the experimental measurements. A
scenario accounting for intermediate $c\bar(c)$ interactions is proposed that
reproduces the data at low- and mid-range transverse momenta P_T from the
Fermilab Tevatron and BNL Relativistiv Heavy Ion Collider. The J/psi produced
in this manner are polarized predominantly longitudinally.


title: ACTIVIA: Calculation of Isotope Production Cross-sections and Yields

abstract:
  We present a C++ computer package, ACTIVIA, that can calculate target-product
cross-sections and the production and decay yields of isotopes from cosmic ray
activation using data tables and semi-empirical formulae. We describe the
structure and user interface of the computer code as well as provide
comparisons between the calculations and experimental results. We also outline
suggestions on how the code can be improved and extended for other
applications.


title: Exact solutions for the populations of the n-level ion

abstract:
  We present a matrix solution to the full equations of statistical equilibrium
that give the energy level populations of collisionally-excited ions in
photoionised gaseous nebulae. The rationale for such a calculation is to
maintain a parity between improvements in the quantum-mechanically evaluated
values for collision strengths and transition probabilities from the Iron and
Opacity Projects on the one hand, and 3D photoionisation codes such as MOCASSIN
and astrophysical software for producing nebular diagnostics such as the
Nebular package for IRAF, on the other. We have taken advantage of the fact
that mathematics programs such as MATLAB and Mathematica have proven to be very
adept at symbolic manipulation providing a route to exact solutions for the
n-level ion. In particular, we have avoided the substitution of estimated
values. We provide the matrix solution for the 5-level ion as an example and
show how the equations faithfully reduce to the exact solution for the 3-level
ion. Through the forbidden line ratio R23, we compare the exact solution with
a) that obtained from the observed emission of the spherical planetary nebula
Abell 39, b) 3D Monte-Carlo photoionisation modelling of the same nebula, c)
the approximate 5-level program TEMDEN and d) the exact 3-level ion. The
general solution presented here means that programs for the calculation of
level populations can obtain solutions for ions with a user-specified number of
excited levels. The use of a separate and updatable database of atomic and
ionic constants such as that provided by NIST, means that software of more
general application can now be made available; particularly for the study of
high excitation objects such as active galactic nebulae (AGNs) and supernovae
(SNs) where higher excited levels become significant.


title: Quasar Clustering at $25\kpch$ from a Complete Sample of Binaries

abstract:
  We present spectroscopy of binary quasar candidates selected from Data
Release 4 of the Sloan Digital Sky Survey (SDSS DR4) using Kernel Density
Estimation (KDE). We present 27 new sets of observations, 10 of which are
binary quasars, roughly doubling the number of known $g < 21$ binaries with
component separations of 3 to 6". Only 3 of 49 spectroscopically identified
objects are non-quasars, confirming that the quasar selection efficiency of the
KDE technique is $\sim95$%. Several of our observed binaries are
wide-separation lens candidates that merit additional higher-resolution
observations. One interesting pair may be an M star binary, or an M star-binary
quasar superposition. Our candidates are initially selected by UV-excess ($u-g
< 1$), but are otherwise selected irrespective of the relative colors of the
quasar pair, and we thus use them to suggest optimal color similarity and
photometric redshift approaches for targeting binary quasars, or projected
quasar pairs. From a sample that is complete on proper scales of $23.7 <
R_{prop} < 29.7\kpch$, we determine the projected quasar correlation function
to be $W_p=24.0 \pm^{16.9}_{10.8}$, which is $2\sigma$ lower than recent
estimates. We argue that our low $W_p$ estimates may indicate redshift
evolution in the quasar correlation function from $z\sim1.9$ to $z\sim1.4$ on
scales of $R_{prop} \sim25\kpch$. The size of this evolution broadly tracks
quasar clustering on larger scales, consistent with merger-driven models of
quasar origin. Although our sample alone is insufficient to detect evolution in
quasar clustering on small scales, an $i$-selected DR6 KDE quasar catalog,
which will contain several hundred $z \leqsim 5$ binary quasars, could easily
constrain any clustering evolution at $R_{prop} \sim25\kpch$.


title: On the mathematical origin of quantum space-time

abstract:
  An Euclidean topological space E is homeomorphic to the subset of
delta-functions of the space D'(E) of Schwartz distributions on E. Herewith,
any smooth function of compact support on E is extended onto D'(E). One can
think of these extensions as sue generis quantum deformations. In quantum
models, one therefore should replace integration of functions over E with that
over D(E).


title: On Brill-Noether loci over Quot schemes and a Torelli theorem

abstract:
  We prove a non abelian Torelli type result for smooth projective curves by
working in the derived category of some associated polarized Quot schemes and
defining Brill-Noether loci and Abel-Jacobi maps on them.


title:
Realization and application of a 111 million pixel backside-illuminated
  detector and camera

abstract:
  A full-wafer, 10,580 $\times$ 10,560 pixel (95 $\times$ 95 mm) CCD was
designed and tested at Semiconductor Technology Associates (STA) with 9 um
square pixels and 16 outputs. The chip was successfully fabricated in 2006 at
DALSA and some performance results are presented here. This program was funded
by the Office of Naval Research through a Small Business Innovation in Research
(SBIR) program requested by the U.S. Naval Observatory for its next generation
astrometric sky survey programs. Using Leach electronics, low read-noise output
of the 111 million pixels requires 16 seconds at 0.9 MHz. Alternative
electronics developed at STA allow readout at 20 MHz. Some modifications of the
design to include anti-blooming features, a larger number of outputs, and use
of p-channel material for space applications are discussed.


title: On perturbative field theory and twistor string theory

abstract:
  It is well-known that perturbative calculations in field theory can lead to
far simpler answers than the Feynman diagram approach might suggest. In some
cases scattering amplitudes can be constructed for processes with any desired
number of external legs yielding compact expressions which are inaccessible
from the point of view of conventional perturbation theory. In this thesis we
discuss some attempts to address the nature of this underlying simplicity and
then use the results to calculate some previously unknown amplitudes of
interest. Witten's twistor string theory is introduced and the CSW rules at
tree-level and one-loop are described. We use these techniques to calculate the
one-loop gluonic MHV amplitudes in N=1 super-Yang-Mills as a verification of
their validity and then proceed to evaluate the general MHV amplitudes in pure
Yang-Mills with a scalar running in the loop. This latter amplitude is a new
result in QCD. In addition to this, we review some recent on-shell recursion
relations for tree-level amplitudes in gauge theory and apply them to gravity.
As a result we present a new compact form for the n-graviton MHV amplitudes in
general relativity. The techniques and results discussed are relevant to the
understanding of the structure of field theory and gravity and the
non-supersymmetric Yang-Mills amplitudes in-particular are pertinent to
background processes at the LHC. The gravitational recursion relations provide
new techniques for perturbative gravity and have some bearing on the
ultraviolet properties of Einstein gravity.


title: Rotating De Sitter Space

abstract:
  An exact solution of the vacuum Einstein equations with a cosmological
constant is exhibited which can perhaps be used to describe the interior of
compact rotating objects. The physical part of this solution has the topology
of a torus, which may shed light on the origin of highly collimated jets from
compact objects.


title: Quasi-fractal sets in space

abstract:
  The focus here is on connected fractal sets with topological dimension 1 and
a lot of topological activity, and their connections with analysis.


title: Energy resolution improvement in room-temperature CZT detectors

abstract:
  We present methods to improve the energy resolution of single-channel,
room-temperature Cadmium-Zinc-Telluride (CZT) detectors. A new preamplifier
design enables the acquisition of the actual transient current from the
crystals and straightforward data analysis methods yield unprecedented energy
resolution for our test-detectors. These consist of an eV-CAPture Plus crystal
as standard and 1 cm cube Frisch collar crystals created in-house from
low-grade coplanar grid detectors. Energy resolutions of 1.9% for our collar
detectors and 0.8% for the eV crystal at 662 keV were obtained. The latter
compares favourably to the best existing energy resolution results from pixel
detectors.


title: Effective gluon mass and infrared fixed point in QCD

abstract:
  We report on a special type of solutions for the gluon propagator of pure
QCD, obtained from the corresponding non-linear Schwinger-Dyson equation
formulated in the Feynman gauge of the background field method. These solutions
reach a finite value in the deep infrared and may be fitted using a massive
propagator, with the crucial characteristic that the effective ``mass''
employed depends on the momentum transfer. Specifically, the gluon mass falls
off as the inverse square of the momentum, as expected from the
operator-product expansion. In addition, one may define a dimensionless
quantity, which constitutes the generalization in a non-Abelian context of the
universal QED effective charge. This strong effective charge displays
asymptotic freedom in the ultraviolet whereas in the low-energy regime it
freezes at a finite value, giving rise to an infrared fixed point for QCD.


title:
Near-field imaging and frequency tuning of a high-Q photonic crystal
  membrane microcavity

abstract:
  We discuss experimental studies of the interaction between a nanoscopic
object and a photonic crystal membrane resonator of quality factor Q=55000. By
controlled actuation of a glass fiber tip in the near-field of a photonic
crystal, we constructed a complete spatio-spectral map of the resonator mode
and its coupling with the fiber-tip. On the one hand, our findings demonstrate
that scanning probes can profoundly influence the optical characteristics and
the near-field images of photonic devices. On the other hand, we show that the
introduction of a nanoscopic object provides a low-loss method for on-command
tuning of a photonic crystal resonator frequency. Our results are in a very
good agreement with the predictions of a combined numerical/analytical theory.


title: Deep MMT Transit Survey of the Open Cluster M37 II: Variable Stars

abstract:
  We have conducted a deep ($15 \la r \la 23$), 20 night survey for transiting
planets in the intermediate age ($\sim 550 {\rm Myr}$) open cluster M37 (NGC
2099) using the Megacam wide-field mosaic CCD camera on the 6.5m Multiple
Mirror Telescope (MMT). In this paper we present a catalog and light curves for
1445 variable stars; 1430 (99%) of these are new discoveries. We have
discovered 20 new eclipsing binaries and 31 new short period ($P < 1 {\rm
day}$) pulsating stars. The bulk of the variables are most likely rapidly
rotating young low-mass stars, including a substantial number ($\ga 500$) that
are members of the cluster. We identify and analyze five particularly
interesting individual variables including a previously identified variable
which we suggest is probably a hybrid $\gamma$ Doradus/$\delta$ Scuti pulsator,
two possible quiescent cataclysmic variables, a detached eclipsing binary (DEB)
with at least one $\gamma$ Doradus pulsating component (only the second such
variable found in an eclipsing binary), and a low mass ($M_{P} \sim M_{S} \sim
0.6 M_{\odot}$) DEB that is a possible cluster member. A preliminary
determination of the physical parameters for the DEB+$\gamma$ Doradus system
yields $M_{P} = 1.58 \pm 0.04 M_{\odot}$, $M_{S} = 1.58 \pm 0.04 M_{\odot}$,
$R_{P} = 1.39 \pm 0.07 R_{\odot}$ and $R_{S} = 1.38 \pm 0.07 R_{\odot}$.


title: The Australia Telescope 20 GHz (AT20G) Survey: The Bright Source Sample

abstract:
  The Australia Telescope 20 GHz (AT20G) Survey is a blind survey of the whole
Southern sky at 20 GHz (with follow-up observations at 4.8 and 8.6 GHz) carried
out with the Australia Telescope Compact Array (ATCA) from 2004 to 2007. The
Bright Source Sample (BSS) is a complete flux-limited subsample of the AT20G
Survey catalogue comprising 320 extragalactic (|b|>1.5 deg) radio sources south
of dec = -15 deg with S(20 GHz) > 0.50 Jy. Of these, 218 have near simultaneous
observations at 8 and 5 GHz. In this paper we present an analysis of radio
spectral properties in total intensity and polarisation, size, optical
identifications and redshift distribution of the BSS sources. The analysis of
the spectral behaviour shows spectral curvature in most sources with spectral
steepening that increases at higher frequencies (the median spectral index
\alpha, assuming S\propto \nu^\alpha, decreases from \alpha_{4.8}^{8.6}=0.11
between 4.8 and 8.6 GHz to \alpha_{8.6}^{20}=-0.16 between 8.6 and 20 GHz),
even if the sample is dominated by flat spectra sources (85 per cent of the
sample has \alpha_{8.6}^{20}>-0.5). The almost simultaneous spectra in total
intensity and polarisation allowed us a comparison of the polarised and total
intensity spectra: polarised fraction slightly increases with frequency, but
the shapes of the spectra have little correlation. Optical identifications
provided an estimation of redshift for 186 sources with a median value of 1.20
and 0.13 respectively for QSO and galaxies.


title: Probing the ground state in gauge theories

abstract:
  We consider two very different models of the flux tube linking two heavy
quarks: a string linking the matter fields and a Coulombic description of two
separately gauge invariant charges. We compare how close they are to the
unknown true ground state in compact U(1) and the SU(2) Higgs model.
Simulations in compact U(1) show that the string description is better in the
confined phase but the Coulombic description is best in the deconfined phase;
the last result is shown to agree with analytical calculations. Surprisingly in
the non-abelian theory the Coulombic description is better in both the Higgs
and confined phases. This indicates a significant difference in the width of
the flux tubes in the two theories.


title: Complete 1-loop test of AdS/CFT

abstract:
  We analyze nested Bethe ansatz (NBA) and the corresponding finite size
corrections. We find an integral equation which describes these corrections in
a closed form. As an application we considered the conjectured
Beisert-Staudacher (BS) equations with the Hernandez-Lopez dressing factor
where the finite size corrections should reproduce generic one (worldsheet)
loop computations around any classical superstring motion in the AdS_5 x S^5
background with exponential precision in the large angular momentum of the
string states. Indeed, we show that our integral equation can be interpreted as
a sum over all physical fluctuations and thus prove the complete 1-loop
consistency of the BS equations. In other words we demonstrate that any local
conserved charge (including the AdS Energy) computed from the BS equations is
indeed given at 1-loop by the sum of charges of fluctuations up to
exponentially suppressed contributions. Contrary to all previous studies of
finite size corrections, which were limited to simple configurations inside
rank one subsectors, our treatment is completely general.


title: Non-BPS Attractors in 5d and 6d Extended Supergravity

abstract:
  We connect the attractor equations of a certain class of N=2, d=5
supergravities with their (1,0), d=6 counterparts, by relating the moduli space
of non-BPS d=5 black hole/black string attractors to the moduli space of
extremal dyonic black string d=6 non-BPS attractors. For d = 5 real special
symmetric spaces and for N = 4,6,8 theories, we explicitly compute the flat
directions of the black object potential corresponding to vanishing eigenvalues
of its Hessian matrix. In the case N = 4, we study the relation to the (2,0),
d=6 theory. We finally describe the embedding of the N=2, d=5 magic models in
N=8, d=5 supergravity as well as the interconnection among the corresponding
charge orbits.


title: Homotopy type and v1-periodic homotopy groups of p-compact groups

abstract:
  We determine the v1-periodic homotopy groups of all irreducible p-compact
groups (BX,X). In the most difficult, modular, cases, we follow a direct path
from their associated invariant polynomials to these homotopy groups. We show
that, if p is odd, every irreducible p-compact group has X of the homotopy type
of a product of explicit spaces related to p-completed Lie groups.


title: Structure formation and the origin of dark energy

abstract:
  Cosmological constant a.k.a. dark energy problem is considered to be one
major challenge in modern cosmology. Here we present a model where large scale
structure formation causes spatially-flat FRW universe to fragment into
numerous `FRW islands' surrounded by vacuum. We show that this mechanism can
explain the origin of dark energy as well as the late time cosmic acceleration.
This explanation of dark energy does not require any exotic matter source nor
an extremely fine-tuned cosmological constant. This explanation is given within
classical general relativity and relies on the fact that our universe has been
undergoing structure formation since its recent past.


title: Family Unification with SO(10)

abstract:
  Unification based on the group SO(10)^3 \times S_3 is studied. Each family
has its own SO(10) group, and the S_3 permutes the three families and SO(10)
factors. This is the maximal local symmetry for the known fermions. Family
unification is achieved in the sense that all known fermions are in a single
irreducible multiplet of the symmetry. The symmetry suppresses SUSY flavor
changing effects by making all squarks and sleptons degenerate in the symmetry
limit. Doublet-triplet splitting can arise simply, and non-trivial structure of
the quark and lepton masses emerges from the gauge symmetry, including the
"doubly lopsided" form.


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

abstract:
  We present maps of 14.4 deg^2 of the Ophiuchus dark clouds observed by the
Spitzer Space Telescope Multiband Imaging Photometer for Spitzer (MIPS). These
high quality maps depict both numerous point sources as well as extended dust
emission within the star-forming and non-star-forming portions of these clouds.
Using PSF-fitting photometry, we detect 5779 sources at 24 um and 81 sources at
70 um at the 10 sigma level of significance. Three hundred twenty-three
candidate young stellar objects (YSOs) were identified according to their
positions on the MIPS/2MASS K versus K$-$[24] color-magnitude diagrams as
compared to 24 um detections in the SWIRE extragalactic survey. We find that
more than half of the YSO candidates, and almost all the ones with protostellar
Class I spectral energy distributions, are confined to the known cluster and
aggregates.


title: Kliem and Toeroek Reply

abstract:
  Reply to Comment on "Torus Instability" by J. Chen, Phys. Rev. Lett. 99,
099501 (2007). Refers to "Torus Instability" by Kliem and Toeroek, Phys. Rev.
Lett. 96, 255002 (2006).


title:
Role of Resonances in Heavy Meson Processes within Standard Model and
  Beyond

abstract:
  The effective theory based on combined chiral and heavy quark symmetry, the
heavy meson chiral perturbation theory, is applied to studying the role of
resonances in various processes of heavy mesons within and beyond the Standard
Model. Chiral corrections including both positive and negative parity heavy
meson doublets are calculated to the effective strong couplings featuring in
the effective theory leading order interaction Lagrangian, to the Isgur-Wise
functions in semileptonic B to D decays and to the complete set of
supersymmetric four-quark operators mediating heavy neutral meson mixing. Bare
values of the effective strong couplings are extracted from the measured decay
widths of charmed resonances. Chiral behavior of the couplings, Isgur-Wise
functions and heavy meson bag parameters is studied in the leading logarithmic
approximation. In semileptonic heavy to light decays we determine resonance
contributions to the various form factors within an effective theory inspired
model at zero recoil. We employ a form factor parameterization based on
effective theory limits to extrapolate our results to the whole kinematical
region in charm decays. We compare our results with experimental data and
lattice calculations. Very rare nonleptonic decays of the B_c meson are studied
within the Standard Model where they are mediated by box loop diagrams, and
within a number of Standard Model extensions. Based on existing experimental
searches for related B meson decays, limits are imposed on some of the models
studied. The most promissing nonleptonic two- and three-body decay channels of
the B_c meson in the search for such new physics contributions are identified.


title: Anomalous Relativistic Tunneling and Exotic Point Interactions

abstract:
  We examine one-dimensional quantum scattering of a Dirac particle off
relativistic potential barriers. With proper considerations of Dirac sea,
existence of anomalous tunneling at zero incident-energy is revealed for a
particular type of relativistic potential having same magnitudes and opposite
signs for scalar and vector components. It is also shown that this leads to an
exotic short range limit of the potentials.


title:
On the spectrum of infinite dimensional random products of compact
  operators

abstract:
  We consider an infinite dimensional separable Hilbert space and its family of
compact integrable cocycles over a dynamical system f. Assuming that f acts in
a compact Hausdorff space X and preserves a Borel regular ergodic measure which
is positive on non-empty open sets, we conclude that there is a residual subset
of cocycles within which, for almost every x, either the Oseledets-Ruelle's
decomposition along the orbit of x is dominated or has a trivial spectrum.


title: Gauge-gravity duality -- Super Yang Mills Quantum Mechanics

abstract:
  We describe the conjectured holographic duality between Yang-Mills quantum
mechanics and type IIa string theory. This duality allows us to use lattice
Monte Carlo simulations to probe the physics of the gravitational theory - for
example, at low energies it provides a computation of black hole entropy in
terms of a sum over microstates of the dual gauge theory. Numerical results are
presented of the 4 supercharge theory at finite temperature


title: The conductivity measure for the Anderson model

abstract:
  We study the ac-conductivity in linear response theory for the Anderson
tight-binding model. We define the electrical ac-conductivity and calculate the
linear-response current at zero temperature for arbitrary Fermi energy. In
particular, the Fermi energy may lie in a spectral region where extended states
are believed to exist.


title:
Noncommutative Field Theory from Quantum Mechanical Space-Space
  Noncommutativity

abstract:
  We investigate the incorporation of space noncommutativity into field theory
by extending to the spectral continuum the minisuperspace action of the quantum
mechanical harmonic oscillator propagator with an enlarged Heisenberg algebra.
In addition to the usual $\star$-product deformation of the algebra of field
functions, we show that the parameter of noncommutativity can occur in
noncommutative field theory even in the case of free fields without
self-interacting potentials.


title: Bowen blend echo-tomography of low mass X-ray binaries

abstract:
  We present simultaneous high time resolution (1-10 Hz) X-ray and optical
observations of the persistent LMXBs Sco X-1 and V801 Ara(=4U 1636-536). In the
case of Sco X-1 we find that the Bowen/HeII emission lags the X-ray
light-curves with a light travel time of ~11-16s which is consistent with
reprocessing in the donor star. We also present the detection of three
correlated X-ray/optical bursts in V801 ara. Although this latter project is
still in progress our preliminary results obtained by subtracting the Continuum
light-curve from the Bowen/HeII data provide evidence of orbital phase
dependent echoes from the companion star.


title: Perturbative finiteness of the three-dimensional Susy QED to all orders

abstract:
  Within the superfield formalism, we study the ultraviolet properties of the
three-dimensional supersymmetric quantum electrodynamics. The theory is shown
to be finite at all loops orders in a particular gauge.


title:
Electronic Structure of Single-Walled Carbon Nanotubes Governed by
  Odd-Electrons Interaction

abstract:
  For the first time, an approach is suggested for the quantitative description
of the electronic structure of single-walled carbon nanotubes and the
prediction of active sites for the tube controlled functionalization in view of
the tube length and ends structure. The approach is based on the tube
characteristic feature connected with odd electrons and is illustrated for a
family involving fragments of arm-chair configured (4,4) single-walled
nanotubes differing by length and end structure. Short and long tubes as well
as tubes with cap end and open end, in the latter case, both hydrogen
terminated and empty, are considered. Algorithms of the quantitative
description of the tubes of any length are suggested. Calculations were
performed in the framework of the single-determinant unrestricted Hartree-Fock
approach.


title: Black Hole Production from High Energy Scattering in AdS/CFT

abstract:
  In this article we show how to set up initial states in ${\cal N} =4$ SYM
theory that correspond to high energy graviton collisions, leading to black
hole formation in $AdS_5\times S^5$. For this purpose, we study states in the
gauge theory that are dual to graviton wavepackets localized at the center of
$AdS_5$, and carrying large angular momentum along the $S^5$. These states are
created by exciting only the s-wave mode of one of the complex adjoint scalars
of SYM. For a single graviton, the state is 1/2 BPS and one can show that it is
dual to a linearized 1/2 BPS geometry in the bulk. Exploiting this dictionary,
we show how to localize the particle's wavefunciton so that the dual linearized
metric has the form of a Aichelburg-Sexl shock wave. One can then put two such
shock waves into a head-on collision, which is known to produce a trapped
surface. Finally, we discuss the prospect of studying graviton scattering
directly at strong coupling in the gauge theory using a reduced model of matrix
quantum mechanics.


title:
Forty-Four Pass Fibre Optic Loop for Improving the Sensitivity of
  Surface Plasmon Resonance Sensors

abstract:
  A forty-four pass fibre optic surface plasmon resonance sensor that enhances
detection sensitivity according to the number of passes is demonstrated for the
first time. The technique employs a fibre optic recirculation loop that passes
the detection spot forty- four times, thus enhancing sensitivity by a factor of
forty-four. Presently, the total number of passes is limited by the onset of
lasing action of the recirculation loop. This technique offers a significant
sensitivity improvement for various types of plasmon resonance sensors that may
be used in chemical and biomolecule detections.


title:
The Outer Disks of Early-Type Galaxies. I. Surface-Brightness Profiles
  of Barred Galaxies

abstract:
  We present a study of 66 barred, early-type (S0-Sb) disk galaxies, focused on
the disk surface brightness profile outside the bar region and the nature of
Freeman Type I and II profiles, their origins, and their possible relation to
disk truncations. This paper discusses the data and their reduction, outlines
our classification system, and presents $R$-band profiles and classifications
for all galaxies in the sample.
  The profiles are derived from a variety of different sources, including the
Sloan Digital Sky Survey (Data Release 5). For about half of the galaxies, we
have profiles derived from more than one telescope; this allows us to check the
stability and repeatability of our profile extraction and classification. The
vast majority of the profiles are reliable down to levels of mu_R ~ 27 mag
arcsec^-2; in exceptional cases, we can trace profiles down to mu_R > 28. We
can typically follow disk profiles out to at least 1.5 times the traditional
optical radius R_25; for some galaxies, we find light extending to ~ 3 R_25.
  We classify the profiles into three main groups: Type I (single-exponential),
Type II (down-bending), and Type III (up-bending). The frequencies of these
types are approximately 27%, 42%, and 24%, respectively, plus another 6% which
are combinations of Types II and III. We further classify Type II profiles by
where the break falls in relation to the bar length, and in terms of the
postulated mechanisms for breaks at large radii ("classical trunction" of star
formation versus the influence of the Outer Lindblad Resonance of the bar). We
also classify the Type III profiles by the probable morphology of the outer
light (disk or spheroid). Illustrations are given for all cases. (Abridged)


title: Distinguished tame supercuspidal representations

abstract:
  This paper studies the behavior of Jiu-Kang Yu's tame supercuspidal
representations relative to involutions of reductive p-adic groups. Symmetric
space methods are used to illuminate various aspects of Yu's construction.
Necessary conditions for a tame supercuspidal representation of G to be
distinguished by (the fixed points of) an involution of G are expressed in
terms of properties of the G-orbit of the associated G-datum. When these
conditions are satisfied, the question of whether a tame supercuspidal
representation is distinguished reduces to the question of whether certain
cuspidal representations of finite groups of Lie type are distinguished
relative to particular quadratic characters. As an application of the main
results, we obtain necessary and sufficient conditions for equivalence of two
of Yu's supercuspidal representations associated to distinct G-data.


title:
OZI violating eight-quark interactions as a thermometer for chiral
  transitions

abstract:
  This work is a follow-up of our recent observation that in the SU(3) flavor
limit with vanishing current quark masses the temperature for the chiral
transition is substantially reduced by adding eight-quark interactions to the
Nambu - Jona-Lasinio Lagrangian with U_A(1) breaking. Here we generalize the
case to realistic light and strange quark masses and confirm our prior result.
Additionally, we demonstrate that depending on the strength of OZI violating
eight-quark interactions, the system undergoes either a rapid crossover or a
first order phase transition. The meson mass spectra of the low lying
pseudoscalars and scalars at T=0 are not sensitive to the difference in the
parameter settings that correspond to these two alternatives, except for the
singlet-octet mixing scalar channels, mainly the sigma meson.


title: Fictitious Cavity Approach to the Casimir Effect

abstract:
  We obtain expressions for the Casimir energy and force following an approach
which may be applied to cavities made up of arbitrary materials. In the case of
planar cavities we obtain the well known Lifshitz formula. The approach is
easily generalizable to other geometries.


title: Spherical characters: the supercuspidal case

abstract:
  We exhibit a basis for the space of spherical characters of a distinguished
supercuspidal representation $\pi$ of a connected reductive $p$-adic group,
subject to the assumption that $\pi$ is obtained via induction from a
representation of an open compact mod centre subgroup. We derive an integral
formula for each spherical character belonging to the basis. This formula
involves integration of a particular kind of matrix coefficient of $\pi$. We
also obtain a similar formula for the function realizing the spherical
character. In addition, we determine, subject to some conditions, which of
these spherical characters vanish identically on an open neighbourhood of the
identity. We verify that the requisite conditions are always satisfied for
distinguished tame supercuspidal representations of groups that split over
tamely ramified extensions.


title: Non-linear Preheating with Scalar Metric Perturbations

abstract:
  We have studied preheating of field perturbations in a 3-dimensional lattice
including the effect of scalar metric perturbations, in two generic models of
inflation: chaotic inflation with a quartic potential, and standard hybrid
inflation. We have prepared the initial state for the classical evolution of
the system with vanishing vector and tensor metric perturbations, consistent
with the constraint equations, the energy and momentum constraints. The
non-linear evolution inevitably generates vector and tensor modes, and this
reflects on how well the constraint equations are fulfilled during the
evolution. The induced preheating of the scalar metric perturbations is not
large enough to backreact onto the fields, but it could affect the evolution of
vector and tensor modes. This is the case in hybrid inflation for some values
of the coupling $g$ and the height of potential $V_0^{1/4}$. For example with
$V_0^{1/4} \simeq 10^{15}$ GeV, preheating of scalar perturbations is such that
their source term in the evolution equation of tensor and vector becomes
comparable to that of the field anisotropic stress.


title: The effect of galaxy mass ratio on merger--driven starbursts

abstract:
  We employ numerical simulations of galaxy mergers to explore the effect of
galaxy mass ratio on merger--driven starbursts. Our numerical simulations
include radiative cooling of gas, star formation, and stellar feedback to
follow the interaction and merger of four disk galaxies. The galaxy models span
a factor of 23 in total mass and are designed to be representative of typical
galaxies in the local Universe. We find that the merger--driven star formation
is a strong function of merger mass ratio, with very little, if any, induced
star formation for large mass ratio mergers. We define a burst efficiency that
is useful to characterize the merger--driven star formation and test that it is
insensitive to uncertainties in the feedback parameterization. In accord with
previous work we find that the burst efficiency depends on the structure of the
primary galaxy. In particular, the presence of a massive stellar bulge
stabilizes the disk and suppresses merger--driven star formation for large mass
ratio mergers. Direct, co--planar merging orbits produce the largest tidal
disturbance and yield that most intense burst of star formation. Contrary to
naive expectations, a more compact distribution of gas or an increased gas
fraction both decrease the burst efficiency. Owing to the efficient feedback
model and the newer version of SPH employed here, the burst efficiencies of the
mergers presented here are smaller than in previous studies.


title: A Bayesian Approach to Network Modularity

abstract:
  We present an efficient, principled, and interpretable technique for
inferring module assignments and for identifying the optimal number of modules
in a given network. We show how several existing methods for finding modules
can be described as variant, special, or limiting cases of our work, and how
the method overcomes the resolution limit problem, accurately recovering the
true number of modules. Our approach is based on Bayesian methods for model
selection which have been used with success for almost a century, implemented
using a variational technique developed only in the past decade. We apply the
technique to synthetic and real networks and outline how the method naturally
allows selection among competing models.


title:
Loop induced interference effects in Higgs Boson plus two jet production
  at the LHC

abstract:
  We calculate the order O(alpha^2 alpha_s^3) interference effect between the
gluon fusion and weak boson fusion processes allowed at the one-loop level in
Higgs boson plus 2 jet production at the LHC. The corresponding one-loop
amplitudes, which have not been considered in the literature so far, are
evaluated analytically using dimensional regularisation and the necessary
master integrals with massive propagators are reported. It is discussed in
detail how various mechanisms conspire to make this contribution numerically
negligible for experimental studies at the LHC.


title:
Self-assembly of polymers or copolymers and ferrofluids leading to
  either 1-d, 2-d or 3-d aggregates decorated with magnetic nanoparticles

abstract:
  A novel type of hybrid colloids is presented, based on the association of
several polymeric systems and ferrofluids. On the one hand, we use inorganic
nanoparticles made of magnetic iron oxide prepared at the LI2C, which response
to a magnetic field of low intensity. On the other hand the organic part is
made either of long linear polyacrylamide chains or of mesoscopic structures
(vesicles and micelles) self-assembled from amphiphile
polybutadiene-b-poly(glutamic acid) di-block copolymers, which conformation is
pH-sensitive.


title:
Uma forma bidimensional que maximiza a resist\^encia aerodin\^amica
  newtoniana

abstract:
  (English)
  In a previous work [Nonlinearity, 20:2271-2287, 2007; arXiv:math/0703895] it
is investigated, by means of computational simulations, shapes of nonconvex
bodies that maximize resistance to its motion on a rarefied medium, considering
that bodies are moving forward and at the same time slowly rotating. Here the
previous results are improved: we obtain a two-dimensional geometric shape that
confers to the body a resistance very close to the supremum value
(R=1.4965<1.5).
  -----
  Resumo (Portuguese)
  Um corpo bidimensional, apresentando um ligeiro movimento rotacional,
desloca-se num meio rarefeito de part\'iculas que colidem com ele de uma forma
perfeitamente el\'astica. Em investiga\c{c}\~oes que os dois primeiros autores
realizaram anteriormente [Nonlinearity, 20:2271-2287, 2007;
arXiv:math/0703895], procuraram-se formas de corpos que maximizassem a
for\c{c}a de travagem do meio ao seu movimento. Dando continuidade a esse
estudo, encetam-se agora novas investiga\c{c}\~oes que culminam num resultado
que representa um grande avan\c{c}o qualitativo relativamente aos previamente
alcan\c{c}ados. Esse resultado, que agora se apresenta, consiste numa forma
bidimensional que confere ao corpo uma resist\^encia muito pr\'oxima do seu
limite te\'orico.


title: Optical Integral in the Cuprates and the Question of Sum Rule Violation

abstract:
  Much attention has been given to a possible violation of the optical sum rule
in the cuprates, and the connection this might have to kinetic energy lowering.
The optical integral is composed of a cut-off independent term (whose
temperature dependence is a measure of the sum rule violation), plus a cut-off
dependent term that accounts for the extension of the Drude peak beyond the
upper bound of the integral. We find that the temperature dependence of the
optical integral in the normal state of the cuprates can be accounted for
solely by the latter term, implying that the dominant contribution to the
observed sum rule `violation' in the normal state is due to the finite cut-off.
This cut-off dependent term is well modeled by a theory of electrons
interacting with a broad spectrum of bosons.


title: Generation of Fourier transform limited heralded single photons

abstract:
  In this paper we study the spectral (temporal) properties of heralded single
photon wavepackets, triggered by the detection of an idler photon in the
process of parametric downconversion. The generated single photons are studied
within the framework of the chronocyclic Wigner function, from which the single
photon spectral width and temporal duration can be computed. We derive specific
conditions on the two-photon joint spectral amplitude which result in both pure
and Fourier- transform limited heralded single photons. Likewise, we present
specific source geometries which lead to the fulfilment of these conditions and
show that one of these geometries leads, for a given pump bandwidth, to the
temporally shortest possible heralded single photon wavepackets.


title: Magnetism of NiMn2O4-Fe3O4 Spinel Interfaces

abstract:
  We investigate the magnetic properties of the isostructural spinel-spinel
interface of NiMn2O4(NMO)-Fe3O4. Although the magnetic transition temperature
of the NMO film is preserved, both bulk and interface sensitive measurements
demonstrate that the interface exhibits strong interfacial magnetic coupling up
to room temperature. While NMO thin films have a ferrimagnetic transition
temperature of 60K, both NiFe2O4 and MnFe2O4 are ferrimagnetic at room
temperature. Our experimental results suggest that these magnetic properties
arise from a thin interdiffused region of (Fe,Mn,Ni)3O4 at the interface
leading to Mn and Ni magnetic properties similar to MnFe2O4 and NiFe2O4.


title: Designing Gapped Soft Functions for Jet Production

abstract:
  Distributions in jet production often depend on a soft function, S, which
describes hadronic radiation between the jets. Near kinematic thresholds S
encodes nonperturbative information, while far from thresholds S can be
computed with an operator product expansion (OPE). We design soft functions for
jets that serve this dual purpose, reducing to the perturbative result in the
OPE region and to a consistent model in the nonperturbative region. We use the
MSbar scheme, and in both regions S displays the appropriate renormalization
group scale dependence. We point out that viable soft function models should
have a gap associated with the minimum hadronic energy deposit. This gap is
connected to the leading O(Lambda_QCD) renormalon ambiguity in jet event
shapes. By defining the gap in a suitable scheme we demonstrate that the
leading renormalon can be eliminated. This improves the convergence of
perturbative results, and also the stability by which non-perturbative
parameters encode the underlying soft physics.


title:
Pseudoclassical description of scalar particle in non-Abelian background
  and path-integral representations

abstract:
  Path-integral representations for a scalar particle propagator in non-Abelian
external backgrounds are derived. To this aim, we generalize the procedure
proposed by Gitman and Schvartsman 1993 of path-integral construction to any
representation of SU(N) given in terms of antisymmetric generators. And for
arbitrary representations of SU(N), we present an alternative construction by
means of fermionic coherent states. From the path-integral representations we
derive pseudoclassical actions for a scalar particle placed in non-Abelian
backgrounds. These actions are classically analyzed and then quantized to prove
their consistency.


title:
Spin-orbit mediated anisotropic spin interaction in interacting electron
  systems

abstract:
  We investigate interactions between spins of strongly correlated electrons
subject to the spin-orbit interaction. Our main finding is that of a novel,
spin-orbit mediated anisotropic spin-spin coupling of the van der Waals type.
Unlike the standard exchange, this interaction does not require the wave
functions to overlap. We argue that this ferromagnetic interaction is important
in the Wigner crystal state where the exchange processes are severely
suppressed. We also comment on the anisotropy of the exchange between spins
mediated by the spin-orbital coupling.


title: Topological confinement in bilayer graphene

abstract:
  We study a new type of one-dimensional chiral states that can be created in
bilayer graphene (BLG) by electrostatic lateral confinement. These states
appear on the domain walls separating insulating regions experiencing the
opposite gating polarity. While the states are similar to conventional
solitonic zero-modes, their properties are defined by the unusual chiral BLG
quasiparticles, from which they derive. The number of zero-mode branches is
fixed by the topological vacuum charge of the insulating BLG state. We discuss
how these chiral states can manifest experimentally, and emphasize their
relevance for valleytronics.


title:
Adaptive Optics Imaging of Lyman Break Galaxies as Progenitors of
  Spheroids in the Local Universe

abstract:
  In order to reveal the stellar mass distribution of z~3 galaxies, we are
conducting deep imaging observations of U-dropout Lyman Break Galaxies (LBGs)
with Adaptive Optics (AO) systems in K-band, which corresponds to rest-frame
V-band of z~3 galaxies. The results of the Subaru intensive-program
observations with AO36/NGS/IRCS indicate that 1) the K-band peaks of some of
the LBGs brighter than K=22.0 mag show significant offset from those in the
optical images, 2) the z~3 Mv* LBGs and serendipitously observed Distant Red
Galaxies (DRGs) have flat profiles similar to disk galaxies in the local
universe (i.e., Sersic with n<2), and 3) the surface stellar mass densities of
the Mv* LBGs are 3-6 times larger than those of disk galaxies at z=0-1.
Considering the lack of n>2 systems among the luminous z~3 LBGs and DRGs, and
their strong spatial clustering, we infer that the dense n<2 disk-like
structures evolve into the n>2 spheroids of nearby galaxies through relaxations
due to major merger events.


title:
Estimates on Monge-Amp\`ere operators derived from a local algebra
  inequality

abstract:
  The goal of this short note is to relate the integrability property of the
exponential $e^{-2\phi}$ of a plurisubharmonic function $\phi$ with isolated or
compactly supported singularities, to a priori bounds for the Monge-Amp\`ere
mass of $(dd^c\phi)^n$. The inequality is valid locally or globally on an
arbitrary open subset $\Omega$ in $\bC^n$. We show that
$\int_\Omega(dd\phi)^n<n^n$ implies $\int_Ke^{-2\phi}<+\infty$ for every
compact subset $K$ in $\Omega$, while functions of the form
$\phi(z)=n\log|z-z_0|$, $z_0\in\Omega$, appear as limit cases. The result is
derived from an inequality of pure local algebra, which turns out a posteriori
to be equivalent to it, proved by A.Corti in dimension $n=2$, and later
extended by L.Ein, T.De Fernex and M.Musta\c{t}\v{a} to arbitrary dimensions.


title:
Parameterization of the Woods-Saxon Potential for Shell-Model
  Calculations

abstract:
  The drastically expanded use of the Woods-Saxon potential in modern day
nuclear physics and the availability of new nuclear data motivated us to review
and optimize the parameters of this potential to the experimental
single-nucleon spectra around the doubly-magic nuclei between $^{16}$O and
$^{208}$Pb. We obtain a parameterization which is applicable over the whole
nuclear chart for nuclides between $^{16}$O and the heaviest elements. Apart
from Coulomb components the obtained parameter set is isospin symmetric. We
demonstrate that the potential provides a good description of the nuclear mean
field leading to quality single-particle spectra, nuclear radii, prediction of
drip-lines, shell closures and other properties. Thus presented Woods-Saxon fit
provides adequate single-particle basis for shell model calculations bridging
over into the continuum.


title: The log-linear group-lasso estimator and its asymptotic properties

abstract:
  We define the group-lasso estimator for the natural parameters of the
exponential families of distributions representing hierarchical log-linear
models under multinomial sampling scheme. Such estimator arises as the solution
of a convex penalized likelihood optimization problem based on the group-lasso
penalty. We illustrate how it is possible to construct an estimator of the
underlying log-linear model using the blocks of nonzero coefficients recovered
by the group-lasso procedure. We investigate the asymptotic properties of the
group-lasso estimator as a model selection method in a double-asymptotic
framework, in which both the sample size and the model complexity grow
simultaneously. We provide conditions guaranteeing that the group-lasso
estimator is model selection consistent, in the sense that, with overwhelming
probability as the sample size increases, it correctly identifies all the sets
of nonzero interactions among the variables. Provided the sequences of true
underlying models is sparse enough, recovery is possible even if the number of
cells grows larger than the sample size. Finally, we derive some central limit
type of results for the log-linear group-lasso estimator.


title: Type II critical phenomena of neutron star collapse

abstract:
  We investigate spherically-symmetric, general relativistic systems of
collapsing perfect fluid distributions. We consider neutron star models that
are driven to collapse by the addition of an initially "in-going" velocity
profile to the nominally static star solution. The neutron star models we use
are Tolman-Oppenheimer-Volkoff solutions with an initially isentropic,
gamma-law equation of state. The initial values of 1) the amplitude of the
velocity profile, and 2) the central density of the star, span a parameter
space, and we focus only on that region that gives rise to Type II critical
behavior, wherein black holes of arbitrarily small mass can be formed. In
contrast to previously published work, we find that--for a specific value of
the adiabatic index (Gamma = 2)--the observed Type II critical solution has
approximately the same scaling exponent as that calculated for an
ultrarelativistic fluid of the same index. Further, we find that the critical
solution computed using the ideal-gas equations of state asymptotes to the
ultrarelativistic critical solution.


title: Autour de la cohomologie de Bott-Chern

abstract:
  The goal of the memoir is to develop a new cohomology theory which
encompasses De Rham and Dolbeault cohomology as well as Deligne Beilinson
cohomology, in the context of general complex analytic manifolds. The special
case of the Iwasawa manifold is investigated as a typical example of what
occurs in the non K\"ahler case. Elementary applications to the Kodaira-Spencer
deformation theory and to the calculation of Chern classes are given.


title: Transport of Molecular Motor Dimers in Burnt-Bridge Models

abstract:
  Dynamics of molecular motor dimers, consisting of rigidly bound particles
that move along two parallel lattices and interact with underlying molecular
tracks, is investigated theoretically by analyzing discrete-state stochastic
continuous-time burnt-bridge models. In these models the motion of molecular
motors is viewed as a random walk along the lattices with periodically
distributed weak links (bridges). When the particle crosses the weak link it
can be destroyed with a probability $p$, driving the molecular motor motion in
one direction. Dynamic properties and effective generated forces of dimer
molecular motors are calculated exactly as a function of a concentration of
bridges $c$ and burning probability $p$ and compared with properties of the
monomer motors. It is found that the ratio of the velocities of the dimer and
the monomer can never exceed 2, while the dispersions of the dimer and the
monomer are not very different. The relative effective generated force of the
dimer (as compared to the monomer) also cannot be larger than 2 for most sets
of parameters. However, a very large force can be produced by the dimer in the
special case of $c=1/2$ for non-zero shift between the lattices. Our
calculations do not show the significant increase in the force generated by
collagenase motor proteins in real biological systems as predicted by previous
computational studies. The observed behavior of dimer molecular motors is
discussed by considering in detail the particle dynamics near burnt bridges.


title:
Star Formation at Very Low Metallicity. IV. Fragmentation Does Not
  Depend on Metallicity for Cold Initial Conditions

abstract:
  Primordial star formation appears to result in stars at least an order of
magnitude more massive than modern star formation. It has been proposed that
the transition from primordial to modern initial mass functions occurs due to
the onset of effective metal line cooling at a metallicity Z/Z_sun = 10^{-3.5}.
However, these simulations neglected molecular hydrogen cooling. We perform
simulations using the same initial conditions, but including molecular cooling,
using a complex network that follows molecular hydrogen formation and also
directly follows carbon monoxide and water. We find that molecular hydrogen
cooling allows roughly equivalent fragmentation to proceed even at zero
metallicity for these initial conditions. The apparent transition just
represents the point where metal line cooling becomes more important than
molecular cooling. In all cases, the fragments are massive enough to be
consistent with models of primordial stellar masses, suggesting that the
transition to the modern initial mass function may be determined by other
physics such as dust formation. We conclude that such additional cooling
mechanisms, combined with the exact initial conditions produced by cosmological
collapse are likely more important than metal line cooling in determining the
initial mass function, and thus that there is unlikely to be a sharp transition
in the initial mass function at Z/Z_sun = 10^{-3.5}.


title: On the Hopf Lemma

abstract:
  The Hopf Lemma for second order elliptic operators is proved to hold in
domains with $C^{1,\alpha}$, and even less regular, boundaries. It need not
hold for $C^1$ boundaries. Corresponding results are proved for second order
parabolic operators.


title: Brane tunneling and virtual brane-antibrane pairs

abstract:
  We survey barrier penetration by quantum tunneling for four cases:
nonrelativistic point particles, scalar fields, relativistic point particles,
and DBI branes. We examine two novel features that arise for DBI brane
tunneling: the rate can sometimes increase as the barrier gets higher; and the
instanton "wrinkles". We show that these features can be understood as the
effect of the quantum sea of virtual brane-antibrane pairs. This sea
exponentially augments the decay rate, with possible cosmological consequences.


title:
Robustness of operator quantum error correction with respect to
  initialization errors

abstract:
  In the theory of operator quantum error correction (OQEC), the notion of
correctability is defined under the assumption that states are perfectly
initialized inside a particular subspace, a factor of which (a subsystem)
contains the protected information. If the initial state of the system does not
belong entirely to the subspace in question, the restriction of the state to
the otherwise correctable subsystem may not remain invariant after the
application of noise and error correction. It is known that in the case of
decoherence-free subspaces and subsystems (DFSs) the condition for perfect
unitary evolution inside the code imposes more restrictive conditions on the
noise process if one allows imperfect initialization. It was believed that
these conditions are necessary if DFSs are to be able to protect imperfectly
encoded states from subsequent errors. By a similar argument, general OQEC
codes would also require more restrictive error-correction conditions for the
case of imperfect initialization. In this study, we examine this requirement by
looking at the errors on the encoded state. In order to quantitatively analyze
the errors in an OQEC code, we introduce a measure of the fidelity between the
encoded information in two states for the case of subsystem encoding. A major
part of the paper concerns the definition of the measure and the derivation of
its properties. In contrast to what was previously believed, we obtain that
more restrictive conditions are not necessary neither for DFSs nor for general
OQEC codes. This is because the effective noise that can arise inside the code
as a result of imperfect initialization is such that it can only increase the
fidelity of an imperfectly encoded state with a perfectly encoded one.


title: Meridional Almost Normal Surfaces in Knot Complements

abstract:
  Suppose $K$ is a knot in a closed 3-manifold $M$ such that $\bar{M-N(K)}$ is
irreducible. We show that for any positive integer $b$ there exists a
triangulation of $\bar{M-N(K)}$ such that any weakly incompressible bridge
surface for $K$ of $b$ bridges or fewer is isotopic to an almost normal bridge
surface.


title:
Maximum Likelihood Estimation in Latent Class Models For Contingency
  Table Data

abstract:
  Statistical models with latent structure have a history going back to the
1950s and have seen widespread use in the social sciences and, more recently,
in computational biology and in machine learning. Here we study the basic
latent class model proposed originally by the sociologist Paul F. Lazarfeld for
categorical variables, and we explain its geometric structure. We draw
parallels between the statistical and geometric properties of latent class
models and we illustrate geometrically the causes of many problems associated
with maximum likelihood estimation and related statistical inference. In
particular, we focus on issues of non-identifiability and determination of the
model dimension, of maximization of the likelihood function and on the effect
of symmetric data. We illustrate these phenomena with a variety of synthetic
and real-life tables, of different dimension and complexity. Much of the
motivation for this work stems from the "100 Swiss Francs" problem, which we
introduce and describe in detail.


title:
Dynamics of proteins: Light scattering study of dilute and dense
  colloidal suspensions of eye lens homogenates

abstract:
  We report a dynamic light scattering study on protein suspensions of bovine
lens homogenates at conditions (pH and ionic strength) similar to the
physiological ones. Light scattering data were collected at two temperatures,
20 oC and 37 oC, over a wide range of concentrations from the very dilute limit
up to the dense regime approaching to the physiological lens concentration. A
comparison with experimental data from intact bovine lenses was advanced
revealing differences between dispersions and lenses at similar concentrations.
In the dilute regime two scattering entities were detected and identified with
the long-time, self-diffusion modes of alpha-crystallins and their aggregates,
which naturally exist in lens nucleus. Self-diffusion coefficients are
temperature insensitive, whereas the collective diffusion coefficient depends
strongly on temperature revealing a reduction of the net repulsive
interparticle forces with lowering temperature. While there are no rigorous
theoretical approaches on particle diffusion properties for multi-component,
non-ideal hard-sphere, polydispersed systems, as the suspensions studied here,
a discussion of the volume fraction dependence of the long-time, self-diffusion
coefficient in the context of existing theoretical approaches was undertaken.
This study is purported to provide some insight into the complex light
scattering pattern of intact lenses and the interactions between the
constituent proteins that are responsible for lens transparency. This would
lead to understand basic mechanisms of specific protein interactions that lead
to lens opacification (cataract) under pathological conditions.


title:
L'articolo di Ettore Majorana su "Il valore delle Leggi Statistiche
  nella Fisica e nelle Scienze Sociali" (Ettore Majorana's article on "The
  value of Statistical Laws in Physics and in Social Sciences")

abstract:
  The mentioned article was written by Ettore Majorana, in a partially
educational way, for a journal of Sociology; but he gave up publishing it (and
threw it away). It appeared posthumous, thanks to Giovanni Gentile Jr. (the
inventor of "parastatistics") in "Scientia" 36 (1942) 58-66. It has not been
re-published, in Italian, till the beginning of 2006, when we made known some
abridgements of it by Italian newspapers and by the journal "Fisica in
Medicina". We don't know when was it written: perhaps in 1930. However, its
central theme was still alive in Majorana's mind in 1934: in fact, on July 27,
1934, he will write to G.Gentile Jr. to expect that <<soon it will be generally
understood that science ceased to be a justification for the vulgar
materialism>>. Here, in Part I, we present a suitable reduction, edited by us,
of Majorana's article; while in Part II we add a complete transcription of it.
[Since the paper which appeared in "Scientia" contains some errors in the
interpretation of Majorana's handwriting, the present versions have been very
slightly "corrected" by us]. For the translations into English of Majorana's
paper, see Refs.[5,6] below. A more extended Summary (in English, besides in
Italian) can be found at the beginning of the present e-print. The interested
reader can found all the known biographical documents --apart from the ones
discovered during the last two years-- in the book by E.Recami, "Il Caso
Majorana: Epistolario, Testimonianze, Documenti" (Mondadori, Milan, 1987 and
1991; Di Renzo Editore, Rome, 2000 and 2002); and in the e-prints
arXiv:physics/9810023v4 [physics.hist-ph]; arXiv:0708.2855v1 [physics.hist-ph];
and arXiv:0709.1183 [physics.hist-ph].


title:
Extraction of the Axial Nucleon Form Factor from Neutrino Experiments on
  Deuterium

abstract:
  We present new parameterizations of vector and axial nucleon form factors. We
maintain an excellent descriptions of the form factors at low momentum
transfers ($Q^2$), where the spatial structure of the nucleon is important, and
use the Nachtman scaling variable $\xi$ to relate elastic and inelastic form
factors and impose quark-hadron duality constraints at high $Q^2$ where the
quark structure dominates. We use the new vector form factors to re-extract
updated values of the axial form factor from $\numu$ experiments on deuterium.
We obtain an updated world average value from $\numu$d, $\numubar$H and pion
electroproduction experiments of $M_{A}$ = $1.014 \pm 0.014 GeV/c^2$. Our
parameterizations are useful in modeling $\nu$ interactions at low energies
(e.g. for $\numu$ oscillations experiments). The predictions for high $Q^2$ can
be tested in the next generation electron and $\numu$ scattering experiments.


title: Jets and Tori in Proto-Planetary Nebulae: Observations vs. Theory

abstract:
  We report on a study of the time sequence for the appearance of high-velocity
jets and equatorial tori in the transition of stars from the asymptotic giant
branch to the planetary nebulae phase. Jets and tori are prominent features of
this evolution, but their origins are uncertain. Using the kinematics of
molecular tori and molecular or optical jets, we determine the ejection
histories for a sample of well-observed cases. We find that jets and tori
develop nearly simultaneously. We also find evidence that jets appear slightly
later than tori, with a typical jet-lag of a few hundred years. The
reconstructed time-lines of this sequence provide good evidence that jets and
tori are physically related, and they set new constraints on jet formation
scenarios. Some scenarios are ruled out or rendered implausible, and others are
challenged at a quantitative level.


title: Polyelectrolyte Condensation Induced by Linear Cations

abstract:
  We examine the role of the condensing agent in the formation of
polyelectrolyte bundles, via grand-canonical Monte Carlo simulations. Following
recent experiments we use linear, rigid divalent cations of various lengths to
induce condensation. Our results clarify and explain the experimental results
for short cations. For longer cations we observe novel condensation behavior
owing to alignment of the cations. We also study the role of the
polyelectrolyte surface charge density, and find a nonmonotonic variation in
bundle stability. This nonmonotonicity captures two trends that have been
observed in separate experiments.


title:
Towards the Secrecy Capacity of the Gaussian MIMO Wire-tap Channel: The
  2-2-1 Channel

abstract:
  We find the secrecy capacity of the 2-2-1 Gaussian MIMO wire-tap channel,
which consists of a transmitter and a receiver with two antennas each, and an
eavesdropper with a single antenna. We determine the secrecy capacity of this
channel by proposing an achievable scheme and then developing a tight upper
bound that meets the proposed achievable secrecy rate. We show that, for this
channel, Gaussian signalling in the form of beam-forming is optimal, and no
pre-processing of information is necessary.


title:
Galois actions on torsion points of universal one-dimensional formal
  modules

abstract:
  Let $F$ be a local non-Archimedean field with ring of integers $o$. Let $\bf
X$ be a one-dimensional formal $o$-module of $F$-height $n$ over the algebraic
closure of the residue field of $o$. By the work of Drinfeld, the universal
deformation $X$ of $\bf X$ is a formal group over a power series ring $R_0$ in
$n-1$ variables over the completion of the maximal unramified extension of $o$.
For $h \in \{0,...,n-1\}$ let $U_h$ be the subscheme of $\Spec(R_0)$ where the
connected part of the associated divisible module of $X$ has height $h$. Using
the theory of Drinfeld level structures we show that the representation of the
fundamental group of $U_h$ on the Tate module of the etale quotient is
surjective.


title:
Passing to an effective 4D phantom cosmology from 5D vacuum theory of
  gravity

abstract:
  Starting from a five-dimensional (5D) vacuum theory of gravity where the
extra coordinate is considered as noncompact, we investigate the possibility of
inducing four-dimensional (4D) phantom scenarios by applying form-invariance
symmetry transformations. In particular we obtain phantom scenarios for two
cosmological frameworks. In the first framework we deal with an induced 4D
de-Sitter expansion and in the second one a 4D induced model where the
expansion of the universe is dominated by a decreasing cosmological parameter
$\Lambda(t)$ is discussed.


title: An analytical solution of Monge differential equation

abstract:
  We present the exact solution to the non linear Monge differential equation
lambda(x, t)lambdax(x, t) = lambdat(x, t). It is widely accepted that the Monge
equation is equivalent to the ODE d2X/dt2= 0 of free motion for particular
conditions. Furthermore, the Monge Type equations are connected with X =
F(dX/dt, X; t), which can be integrated with quadratures [1]. Other asymptotic
solutions are discussed, see e.g. [2]. The solution was reached with
calculations that depend upon dimensional representation, which is given by (x,
t) coordinates. We present this analytical solution to the Monge differential
equation as an implicit solution.


title: Locally Adaptive Nonparametric Binary Regression

abstract:
  A nonparametric and locally adaptive Bayesian estimator is proposed for
estimating a binary regression. Flexibility is obtained by modeling the binary
regression as a mixture of probit regressions with the argument of each probit
regression having a thin plate spline prior with its own smoothing parameter
and with the mixture weights depending on the covariates. The estimator is
compared to a single spline estimator and to a recently proposed locally
adaptive estimator. The methodology is illustrated by applying it to both
simulated and real examples.


title:
Spin phonon induced colinear order and magnetization plateaus in
  triangular and kagome antiferromagnets. Applications to CuFeO_2

abstract:
  Coupling between spin and lattice degrees of freedom are important in
geometrically frustrated magnets where they can lead to degeneracy lifting and
novel orders. We show that moderate spin-lattice couplings in triangular and
Kagome antiferromagnets can induce complex colinear magnetic orders. When
classical Heisenberg spins on the triangular lattice are coupled to Einstein
phonons, a rich variety of phases emerge, including the experimentally observed
four sublattice state and the five sublattice 1/5th plateau state seen in the
magneto-electric material CuFeO$_2$. In addition we predict magnetization
plateaus at 1/3, 3/7, 1/2, 3/5 and 5/7 at these couplings. Strong spin-lattice
couplings induce a striped colinear state, seen in $\alpha$-NaFeO$_2$ and
MnBr$_2$. On the Kagome lattice, moderate spin-lattice couplings induce
colinear order, but an extensive degeneracy remains.


title: Partial transpose of permutation matrices

abstract:
  The partial transpose of a block matrix M is the matrix obtained by
transposing the blocks of M independently. We approach the notion of partial
transpose from a combinatorial point of view. In this perspective, we solve
some basic enumeration problems concerning the partial transpose of permutation
matrices. More specifically, we count the number of permutations matrices which
are equal to their partial transpose and the number of permutation matrices
whose partial transpose is still a permutation. We solve these problems also
when restricted to symmetric permutation matrices only.


title: Confidence Level and Sensitivity Limits in High Contrast Imaging

abstract:
  In long adaptive optics corrected exposures, exoplanet detections are
currently limited by speckle noise originating from the telescope and
instrument optics, and it is expected that such noise will also limit future
high-contrast imaging instruments for both ground and space-based telescopes.
Previous theoretical analysis have shown that the time intensity variations of
a single speckle follows a modified Rician. It is first demonstrated here that
for a circular pupil this temporal intensity distribution also represents the
speckle spatial intensity distribution at a fix separation from the point
spread function center; this fact is demonstrated using numerical simulations
for coronagraphic and non-coronagraphic data. The real statistical distribution
of the noise needs to be taken into account explicitly when selecting a
detection threshold appropriate for some desired confidence level. In this
paper, a technique is described to obtain the pixel intensity distribution of
an image and its corresponding confidence level as a function of the detection
threshold. Using numerical simulations, it is shown that in the presence of
speckles noise, a detection threshold up to three times higher is required to
obtain a confidence level equivalent to that at 5sigma for Gaussian noise. The
technique is then tested using TRIDENT CFHT and angular differential imaging
NIRI Gemini adaptive optics data. It is found that the angular differential
imaging technique produces quasi-Gaussian residuals, a remarkable result
compared to classical adaptive optic imaging. A power-law is finally derived to
predict the 1-3*10^-7 confidence level detection threshold when averaging a
partially correlated non-Gaussian noise.


title:
Euclidean Jordan Algebras and Generalized Krein parameters of a strongly
  regular graph

abstract:
  Let $\tau$ be a strongly $(n,p;a,c)$ regular graph,such that $0<c<p<n-1,$ $A$
his matrix of adjacency and let ${\cal V}_{n}$ be the Euclidean space spanned
by the powers of $A$ over the reals where the scallar product $\bullet|\bullet$
is defined by $x|y={trace}(x \cdot y).$ In this work ones proves that ${\cal
V}_{n}$ is an Euclidean Jordan algebra of rank 3 when one introduces in ${\cal
V}_{n}$ the usual product of matrices. In this Euclidean Jordan algebra one
defines the modulus of a matrix, and afterwards one defines $|A|^x \forall x\in
\mathbb{R}.$ Working inside the Euclidean Jordan algebra ${\cal V}_{n}$ and
making use of the properties of $|A|^x$ one defines the generalized krein
parameters of the strongly $(n,p;a,c)$ regular graph $\tau$ and finally one
presents necessary conditions over the parameters and the spectra of the $\tau$
strongly $(n,p;a,c)$ regular graph.


title:
The Outburst of the Blazar AO 0235+164 in 2006 December: Shock-in-Jet
  Interpretation

abstract:
  We present the results of polarimetric ($R$ band) and multicolor photometric
($BVRIJHK$) observations of the blazar AO 0235+16 during an outburst in 2006
December. The data reveal a short timescale of variability (several hours),
which increases from optical to near-IR wavelengths; even shorter variations
are detected in polarization. The flux density correlates with the degree of
polarization, and at maximum degree of polarization the electric vector tends
to align with the parsec-scale jet direction. We find that a variable component
with a steady power-law spectral energy distribution and very high optical
polarization (30-50%) is responsible for the variability. We interpret these
properties of the blazar withina model of a transverse shock propagating down
the jet. In this case a small change in the viewing angle of the jet, by
$\lesssim 1^o$, and a decrease in the shocked plasma compression by a factor of
$\sim$1.5 are sufficient to account for the variability.


title:
Interference effects in the counting statistics of electron transfers
  through a double quantum dot

abstract:
  We investigate the effect of quantum interferences and Coulomb interaction on
the counting statistics of electrons crossing a double quantum dot in a
parallel geometry using a generating function technique based on a quantum
master equation approach. The skewness and the average residence time of
electrons in the dots are shown to be the quantities most sensitive to
interferences and Coulomb coupling. The joint probabilities of consecutive
electron transfer processes show characteristic temporal oscillations due to
interference. The steady-state fluctuation theorem which predicts a universal
connection between the number of forward and backward transfer events is shown
to hold even in the presence of Coulomb coupling and interference.


title: Mass gap for gravity localized on Weyl thick branes

abstract:
  We study the properties of a previously found family of thick brane
configurations in a pure geometric Weyl integrable 5D space time, a
non-Riemannian generalization of Kaluza-Klein (KK) theory involving a geometric
scalar field. Thus the 5D theory describes gravity coupled to a
self-interacting scalar field which gives rise to the structure of the thick
branes. Analyzing the graviton spectrum for this class of models, we find that
a particularly interesting situation arises for a special case in which the 4D
graviton is separated from the KK gravitons by a mass gap. The corresponding
effective Schroedinger equation has a modified Poeschl-Teller potential and can
be solved exactly. Apart from the massless 4D graviton, it contains one massive
KK bound state, and the continuum spectrum of delocalized KK modes. We discuss
the mass hierarchy problem, and explicitly compute the corrections to Newton's
law in the thin brane limit.


title: Design of moveable and resizable graphics

abstract:
  We are communicating with computers on two different levels. On upper level
we have a very flexible system of windows: we can move them, resize, overlap or
put side by side. At any moment we decide what would be the best view and
reorganize the whole view easily. Then we start any application, go to the
inner level, and everything changes. Here we are stripped of all the
flexibility and can work only inside the scenario, developed by the designer of
the program. Interface will allow us to change some tiny details, but in
general everything is fixed: graphics is neither moveable, nor resizable, and
the same with controls. Author designed an extremely powerful mechanism of
turning graphical objects and controls into moveable and resizable. This can
not only significantly improve the existing applications, but this will bring
the applications to another level. (To estimate the possible difference, try to
imagine the Windows system without its flexibility and compare it with the
current one.) This article explains in details the construction and use of
moveable and resizable graphical objects.


title: A New Lower Bound on Guard Placement for Wireless Localization

abstract:
  The problem of wireless localization asks to place and orient stations in the
plane, each of which broadcasts a unique key within a fixed angular range, so
that each point in the plane can determine whether it is inside or outside a
given polygonal region. The primary goal is to minimize the number of stations.
In this paper we establish a lower bound of 2n/3 - 1 stations for polygons in
general position, for the case in which the placement of stations is restricted
to polygon vertices, improving upon the existing n/2 lower bound.


title: A pedagogical explanation for the non-renormalizability of gravity

abstract:
  We present a short and intuitive argument explaining why gravity is
non-renormalizable. The argument is based on black-hole domination of the high
energy spectrum of gravity and not on the standard perturbative irrelevance of
the gravitational coupling. This is a pedagogical note, containing textbook
material that is widely appreciated by experts and is by no means original.


title: Dynamic Spin-Polarized Resonant Tunneling in Magnetic Tunnel Junctions

abstract:
  Precisely engineered tunnel junctions exhibit a long sought effect that
occurs when the energy of the electron is comparable to the potential energy of
the tunneling barrier. The resistance of metal-insulator-metal tunnel junctions
oscillates with an applied voltage when electrons that tunnel directly into the
barrier's conduction band interfere upon reflection at the classical turning
points: the insulator-metal interface, and the dynamic point where the incident
electron energy equals the potential barrier inside the insulator. A model of
tunneling between free electron bands using the exact solution of the
Schroedinger equation for a trapezoidal tunnel barrier qualitatively agrees
with experiment.