title:
The real-space clustering of luminous red galaxies around z<0.6 quasars
  in the Sloan Digital Sky Survey

abstract:
  We measure the clustering of a sample of photometrically selected luminous
red galaxies around a low redshift (0.2<z<0.6) sample of quasars selected from
the Sloan Digital Sky Survey Data Release 5. We make use of a new statistical
estimator to obtain precise measurements of the LRG auto-correlations and
constrain halo occupation distributions for them. These are used to generate
mock catalogs which aid in interpreting our quasar-LRG cross correlation
measurements. The cross correlation is well described by a power law with slope
1.8\pm0.1 and r_0=6\pm0.5 h^{-1} Mpc, consistent with observed galaxy
correlation functions. We find no evidence for `excess' clustering on 0.1 Mpc
scales and demonstrate that this is consistent with the results of Serber et al
(2006) and Strand et al (2007), when one accounts for several subtleties in the
interpretation of their measurements. Combining the quasar-LRG cross
correlation with the LRG auto-correlations, we determine a large-scale quasar
bias b_QSO = 1.09\pm0.15 at a median redshift of 0.43, with no observed
redshift or luminosity evolution. This corresponds to a mean halo mass <M>~
10^{12} h^{-1} M_sun, Eddington ratios from 0.01 to 1 and lifetimes less than
10^{7} yr. Using simple models of halo occupation, these correspond to a number
density of quasar hosts greater than 10^{-3} h^{3} Mpc^{-3} and stellar masses
less than 10^{11} h^{-1} M_sun. The small-scale clustering signal can be
interpreted with the aid of our mock LRG catalogs, and depends on the manner in
which quasars inhabit halos. We find that our small scale measurements are
inconsistent with quasar positions being randomly subsampled from halo centers
above a mass threshold, requiring a satellite fraction > 25 per cent.


title: New no-go theorems for cosmic acceleration with extra dimensions

abstract:
  We describe new no-go theorems for producing four-dimensional accelerating
universes from warped dimensional reduction. The new theorems improve upon
previous results by including dynamical extra dimensions and by treating
four-dimensional universes that are not precisely de Sitter. The theorems show
there exists a threshold four-dimensional equation-of-state parameter w below
which the number of e-foldings of expansion is bounded, and give expressions
for the maximum number of allowed e-foldings. In the generic case, the bound
must be satisfied if the higher-dimensional theory satisfies the strong energy
condition. If the compactification manifold M is one-dimensional, or if its
(intrinsic) Ricci scalar R is identically zero, then the bound must be
satisfied if the higher-dimensional theory satisfies the null energy condition.


title:
General two-order-parameter Ginzburg-Landau model with quadratic and
  quartic interactions

abstract:
  Ginzburg-Landau model with two order parameters appears in many
condensed-matter problems. However, even for scalar order parameters, the most
general U(1)-symmetric Landau potential with all quadratic and quartic terms
contains 13 independent coefficients and cannot be minimized with
straightforward algebra. Here, we develop a geometric approach that circumvents
this computational difficulty and allows one to study properties of the model
without knowing the exact position of the minimum. In particular, we find the
number of minima of the potential, classify explicit symmetries possible in
this model, establish conditions when and how these symmetries are
spontaneously broken, and explicitly describe the phase diagram.


title: Well-Centered Triangulation

abstract:
  Meshes composed of well-centered simplices have nice orthogonal dual meshes
(the dual Voronoi diagram). This is useful for certain numerical algorithms
that prefer such primal-dual mesh pairs. We prove that well-centered meshes
also have optimality properties and relationships to Delaunay and minmax angle
triangulations. We present an iterative algorithm that seeks to transform a
given triangulation in two or three dimensions into a well-centered one by
minimizing a cost function and moving the interior vertices while keeping the
mesh connectivity and boundary vertices fixed. The cost function is a direct
result of a new characterization of well-centeredness in arbitrary dimensions
that we present. Ours is the first optimization-based heuristic for
well-centeredness, and the first one that applies in both two and three
dimensions. We show the results of applying our algorithm to small and large
two-dimensional meshes, some with a complex boundary, and obtain a
well-centered tetrahedralization of the cube. We also show numerical evidence
that our algorithm preserves gradation and that it improves the maximum and
minimum angles of acute triangulations created by the best known previous
method.


title: On slicing invariants of knots

abstract:
  The slicing number of a knot, $u_s(K)$, is the minimum number of crossing
changes required to convert $K$ to a slice knot. This invariant is bounded
above by the unknotting number and below by the slice genus $g_s(K)$. We show
that for many knots, previous bounds on unknotting number obtained by Ozsvath
and Szabo and by the author in fact give bounds on the slicing number.
Livingston defined another invariant $U_s(K)$ which takes into account signs of
crossings changed to get a slice knot, and which is bounded above by the
slicing number and below by the slice genus. We exhibit an infinite family of
knots $K_n$ with slice genus $n$ and Livingston invariant greater than $n$. Our
bounds are based on restrictions (using Donaldson's diagonalisation theorem or
Heegaard Floer homology) on the intersection forms of four-manifolds bounded by
the double branched cover of a knot.


title: Pair Partitioning in time reversal acoustics

abstract:
  Time reversal of acoustic waves can be achieved efficiently by the persistent
control of excitations in a finite region of the system. The procedure, called
Time Reversal Mirror, is stable against the inhomogeneities of the medium and
it has numerous applications in medical physics, oceanography and
communications. As a first step in the study of this robustness, we apply the
Perfect Inverse Filter procedure that accounts for the memory effects of the
system. In the numerical evaluation of such procedures we developed the Pair
Partitioning method for a system of coupled oscillators. The algorithm,
inspired in the Trotter strategy for quantum dynamics, obtains the dynamic for
a chain of coupled harmonic oscillators by the separation of the system in
pairs and applying a stroboscopic sequence that alternates the evolution of
each pair. We analyze here the formal basis of the method and discuss his
extension for including energy dissipation inside the medium.


title: Holomorphic Motions and Related Topics

abstract:
  In this article we give an expository account of the holomorphic motion
theorem based on work of M\`a\~n\'e-Sad-Sullivan, Bers-Royden, and Chirka.
After proving this theorem, we show that tangent vectors to holomorphic motions
have $|\epsilon \log \epsilon|$ moduli of continuity and then show how this
type of continuity for tangent vectors can be combined with Schwarz's lemma and
integration over the holomorphic variable to produce H\"older continuity on the
mappings. We also prove, by using holomorphic motions, that Kobayashi's and
Teichm\"uller's metrics on the Teichm\"uller space of a Riemann surface
coincide. Finally, we present an application of holomorphic motions to complex
dynamics, that is, we prove the Fatou linearization theorem for parabolic germs
by involving holomorphic motions.


title:
On the Security of ``an efficient and complete remote user
  authentication scheme''

abstract:
  Recently, Liaw et al. proposed a remote user authentication scheme using
smart cards. Their scheme has claimed a number of features e.g. mutual
authentication, no clock synchronization, no verifier table, flexible user
password change, etc. We show that Liaw et al.'s scheme is completely insecure.
By intercepting a valid login message in Liaw et al.'s scheme, any unregistered
user or adversary can easily login to the remote system and establish a session
key.


title:
Observational Constraints on the Formation and Evolution of Globular
  Cluster Systems

abstract:
  This paper reviews some of the observational properties of globular cluster
systems, with a particular focus on those that constrain and inform models of
the formation and dynamical evolution of globular cluster systems. I first
discuss the observational determination of the globular cluster luminosity and
mass function. I show results from new very deep HST data on the M87 globular
cluster system, and discuss how these constrain models of evaporation and the
dynamical evolution of globular clusters. The second subject of this review is
the question of how to account for the observed constancy of the globular
cluster mass function with distance from the center of the host galaxy. The
problem is that a radial trend is expected for isotropic cluster orbits, and
while the orbits are observed to be roughly isotropic, no radial trend in the
globular cluster system is observed. I review three extant proposals to account
for this, and discuss observations and calculations that might determine which
of these is most correct. The final subject is the origin of the very weak
mass-radius relation observed for globular clusters. I discuss how this
strongly constrains how globular clusters form and evolve. I also note that the
only viable current proposal to account for the observed weak mass-radius
relation naturally affects the globular cluster mass function, and that these
two problems may be related.


title: Coriolis Effect in Optics: Unified Geometric Phase and Spin-Hall Effect

abstract:
  We examine the spin-orbit coupling effects that appear when a wave carrying
intrinsic angular momentum interacts with a medium. The Berry phase is shown to
be a manifestation of the Coriolis effect in a non-inertial reference frame
attached to the wave. In the most general case, when both the direction of
propagation and the state of the wave are varied, the phase is given by a
simple expression that unifies the spin redirection Berry phase and the
Pancharatnam--Berry phase. The theory is supported by the experiment
demonstrating the spin-orbit coupling of electromagnetic waves via a surface
plasmon nano-structure. The measurements verify the unified geometric phase,
demonstrated by the observed polarization-dependent shift (spin-Hall effect) of
the waves.


title:
Non-homogeneous polygonal Markov fields in the plane: graphical
  representations and geometry of higher order correlations

abstract:
  We consider polygonal Markov fields originally introduced by Arak and
Surgailis (1989). Our attention is focused on fields with nodes of order two,
which can be regarded as continuum ensembles of non-intersecting contours in
the plane, sharing a number of features with the two-dimensional Ising model.
We introduce non-homogeneous version of polygonal fields in anisotropic
enviroment. For these fields we provide a class of new graphical constructions
and random dynamics. These include a generalised dynamic representation,
generalised and defective disagreement loop dynamics as well as a generalised
contour birth and death dynamics. Next, we use these constructions as tools to
obtain new exact results on the geometry of higher order correlations of
polygonal Markov fields in their consistent regime.


title: Superdisks in Radio Galaxies: Jet-Wind Interactions

abstract:
  Taking a clue from their sharp-edged (strip-like) morphology observed in
several cases, a new mechanism is proposed for the formation of the emission
gaps seen between the radio lobes of many powerful extragalactic double radio
sources. Canonical understanding of the radio gaps invokes either blocking of
the back-flowing lobe plasma by the denser interstellar medium (ISM) of the
host galaxy, or "squeezing" of the radio bridge in the middle through buoyancy
force exerted by either the ISM or the surrounding intra-cluster medium (ICM).
These pictures encounter difficulties in explaining situations where the
sharp-edged radio gaps associated with non-cluster radio galaxies have widths
running into several tens (even hundreds) of kiloparsecs. More particularly,
the required dense high-pressure ISM/ICM is likely to be lacking at least in
the case of high-redshift radio galaxies. We propose here that radio emission
gaps in at least such cases could arise from a dynamical interaction between
the powerful thermal wind outflowing from the active galactic nucleus and the
back-flowing synchrotron plasma in the two radio lobes, which occurs once the
rapidly advancing jets have crossed out of the wind zone into the intergalactic
medium. A simple analytical scheme is presented to explore the plausibility of
the side-ways confinement of the thermal wind by the radio lobe pair, which
would "freeze" pancake shaped conduits in the space, along which the hot, metal
enriched wind from the AGN can escape (roughly orthogonal to the radio axis).
Some other possible consequences of this scenario are pointed out.


title: Brane Inflation is Attractive

abstract:
  We study the phase space of initial conditions for brane inflation, and find
that including the effects of the Dirac-Born-Infeld (DBI) kinetic term
dramatically improves previous estimates on the amount of fine tuning of
initial conditions necessary for inflation, even for models dominated by slow
roll. Two effects turn out to be important for the phase space analysis:
restrictions on the total available phase space due to UV effects in brane
inflation, and the extension of the inflationary attractor to the DBI
inflationary regime. We compare the amount of initial conditions fine tuning
required for a brane inflation model and its standard field theory counterpart
and find that brane inflation decreases the required tuning by several orders
of magnitude.


title: A Long Look at the Be/X-Ray Binaries of the Small Magellanic Cloud

abstract:
  We have monitored 41 Be/X-ray binary systems in the Small Magellanic Cloud
over ~9 years using PCA-RXTE data from a weekly survey program. The resulting
light curves were analysed in search of orbital modulations with the result
that 10 known orbital ephemerides were confirmed and refined, while 10 new ones
where determined. A large number of X-ray orbital profiles are presented for
the first time, showing similar characteristics over a wide range of orbital
periods. Lastly, three pulsars: SXP46.4, SXP89.0 and SXP165 were found to be
misidentifications of SXP46.6, SXP91.1 and SXP169, respectively.


title:
Direct evidence for the suppression of charge stripes in epitaxial
  La$_{1.67}$Sr$_{0.33}$NiO$_4$ thin films

abstract:
  We have successfully grown epitaxial La$_{1.67}$Sr$_{0.33}$NiO$_4$ films with
a small crystalline mosaic using pulsed laser deposition. With synchrotron
radiation, the x-ray diffraction peaks associated with charge stripes have been
successfully observed for relatively thick films. Anomalies due to the
charge-ordering transition have been examined using four-point probe
resistivity measurements. X-ray scattering provides direct evidence for
suppression of the stripe phase in thin samples; the phase disappears for film
thicknesses $\leqslant$ 2600 ~\AA{}. The suppression appears to be a result of
shrinking the stripe phase domains. This may reflect the stripe phase
progressing from nematic to isotropic.


title: Geometric realizations of the multiplihedron and its complexification

abstract:
  We realize Stasheff's multiplihedron geometrically as the moduli space of
stable quilted disks. This generalizes the geometric realization of the
associahedron as the moduli space of stable disks. We show that this moduli
space is the non-negative real part of a complex moduli space of stable scaled
marked curves.


title:
Preservation of stability properties near fixed points of linear
  hamiltonian systems by symplectic integrators

abstract:
  Based on reasonable testing model problems, we study the preservation by
symplectic Runge-Kutta method (SRK) and symplectic partitioned Runge-Kutta
method (SPRK) of structures for fixed points of linear Hamiltonian systems. The
structure-preservation region provides a practical criterion for choosing
step-size in symplectic computation. Examples are given to justify the
investigation.


title:
A manifold of possible physics-laws in a universe where the planck
  constant and speed of light parameters vary

abstract:
  I assume a universe whereby the speed of light and the planck constant are
not constants but instead parameters that vary locally in time-and space. When
describing motion, I am able to derive a modified path integral description at
the quantum level, which offers a natural extension of quantum mechanics. At
the microscopic level, this path integral intuitively describes a physics with
many quantum realities thus leading to a novel concept of manifold of physics,
which can be looked at as a novel action principle. This paradigm reflects the
notion that the observed laws of physics on any given scale are determined by
the underlying distribution of the fundamental parameters (i.e Quantum
Mechanics is just one point on this manifold), thus leading to many possible
physical-law based behaviors. By choosing a Gaussian distribution of the
parameters, a quadratic action term appears in the path-integral, which in
turns leads to a complex classical action (and by continuation a new
description for inertia) at the classical level. In the accompanying manuscript
the classical doublet equation of motion is applied to the Newtonian
gravitation field, and a MOND-like, dark-energy-like, and pioneer-anomaly-like
solutions are derived.


title:
A possible solution to the Dark Matter, Dark Energy, and Pioneer Anomaly
  problems via a VSL approach

abstract:
  I apply the equations of motion derived in the accompanying manuscript for
the classical approximation of the vsl-path integral to the Newtonian
gravitational field in simple geometries. The vsl classical-action, a complex
quantity in this case, yields modified Euler-Lagrange equations. This, in turn,
leads to the emergence of two equations of motions that must be satisfied
concomitantly in order to minimize the complex action. The solutions obtained
to the doublet equation of motion include the MOND force law, a
dark-energy-like omni-present repulsive gravitational force, a pioneer-like
anomaly at the solar system level, and additional predictions, which can be
verified with either careful observations or via additional probes to the outer
solar system. The exercise carried out in this paper exemplifies the
explanatory potential of the vsl-approach, pointing to a potentially new
physics paradigm. Finally, the vsl-approach is not only predictive, but highly
falsifiable, an important ingredient of any physics theory.


title:
Dispersion force for materials relevant for micro and nanodevices
  fabrication

abstract:
  The dispersion (van der Waals and Casimir) force between two semi-spaces are
calculated using the Lifshitz theory for different materials relevant for micro
and nanodevices fabrication, namely, gold, silicon, gallium arsenide, diamond
and two types of diamond-like carbon (DLC), silicon carbide, silicon nitride
and silicon dioxide. The calculations were performed using recent experimental
optical data available in the literature, usually ranging from the far infrared
up to the extreme ultraviolet bands of the electromagnetic spectrum. The
results are presented in the form of a correction factor to the Casimir force
predicted between perfect conductors, for the separation between the
semi-spaces varying from 1 nanometre up to 1 micrometre. The relative
importance of the contributions to the dispersion force of the optical
properties in different spectral ranges is analyzed. The role of the
temperature for semiconductors and insulators is also addressed. The results
are meant to be useful for the estimation of the impact of the Casimir and van
der Waals forces on the operational parameters of micro and nanodevices.


title:
Multiple Access Outerbounds and the Inseparability of Parallel
  Interference Channels

abstract:
  It is known that the capacity of parallel (multi-carrier) Gaussian
point-to-point, multiple access and broadcast channels can be achieved by
separate encoding for each subchannel (carrier) subject to a power allocation
across carriers. In this paper we show that such a separation does not apply to
parallel Gaussian interference channels in general. A counter-example is
provided in the form of a 3 user interference channel where separate encoding
can only achieve a sum capacity of $\log({SNR})+o(\log({SNR}))$ per carrier
while the actual capacity, achieved only by joint-encoding across carriers, is
$3/2\log({SNR}))+o(\log({SNR}))$ per carrier. As a byproduct of our analysis,
we propose a class of multiple-access-outerbounds on the capacity of the 3 user
interference channel.


title: Non-intrinsic superconductivity in InN epilayers: role of Indium Oxide

abstract:
  In recent years there have been reports of anomalous electrical resistivity
and the presence of superconductivity in semiconducting InN layers. By a
careful correlation of the temperature dependence of resistivity and magnetic
susceptibility with structural information from highresolution x-ray
diffraction measurements we show that superconductivity is not intrinsic to InN
and is seen only in samples that show traces of oxygen impurity. We hence
believe that InN is not intrinsically a superconducting semiconductor.


title: New Implementation Framework for Saturation-Based Reasoning

abstract:
  The saturation-based reasoning methods are among the most theoretically
developed ones and are used by most of the state-of-the-art first-order logic
reasoners. In the last decade there was a sharp increase in performance of such
systems, which I attribute to the use of advanced calculi and the intensified
research in implementation techniques. However, nowadays we are witnessing a
slowdown in performance progress, which may be considered as a sign that the
saturation-based technology is reaching its inherent limits. The position I am
trying to put forward in this paper is that such scepticism is premature and a
sharp improvement in performance may potentially be reached by adopting new
architectural principles for saturation. The top-level algorithms and
corresponding designs used in the state-of-the-art saturation-based theorem
provers have (at least) two inherent drawbacks: the insufficient flexibility of
the used inference selection mechanisms and the lack of means for intelligent
prioritising of search directions. In this position paper I analyse these
drawbacks and present two ideas on how they could be overcome. In particular, I
propose a flexible low-cost high-precision mechanism for inference selection,
intended to overcome problems associated with the currently used instances of
clause selection-based procedures. I also outline a method for intelligent
prioritising of search directions, based on probing the search space by
exploring generalised search directions. I discuss some technical issues
related to implementation of the proposed architectural principles and outline
possible solutions.


title: Perfect IFG-formulas

abstract:
  IFG logic is a variant of the independence-friendly logic of Hintikka and
Sandu. We answer the question: ``Which IFG-formulas are equivalent to ordinary
first-order formulas?'' We use the answer to show that the ordinary cylindric
set algebra over a structure can be embedded into a reduct of the IFG-cylindric
set algebra over the structure.


title:
Two-dimensional vortex behavior in highly underdoped YBa_2Cu_3O_{6+x}
  observed by scanning Hall probe microscopy

abstract:
  We report scanning Hall probe microscopy of highly underdoped superconducting
YBa_2Cu_3O_{6+x} with T_c ranging from 5 to 15 K which showed distinct flux
bundles with less than one superconducting flux quantum (Phi_0) through the
sample surface. The sub-Phi_0 features occurred more frequently for lower T_c,
were more mobile than conventional vortices, and occurred more readily when the
sample was cooled with an in-plane field component. We show that these features
are consistent with kinked stacks of pancake vortices.


title:
Domination in graphs with bounded propagation: algorithms, formulations
  and hardness results

abstract:
  We introduce a hierarchy of problems between the \textsc{Dominating Set}
problem and the \textsc{Power Dominating Set} (PDS) problem called the
$\ell$-round power dominating set ($\ell$-round PDS, for short) problem. For
$\ell=1$, this is the \textsc{Dominating Set} problem, and for $\ell\geq n-1$,
this is the PDS problem; here $n$ denotes the number of nodes in the input
graph. In PDS the goal is to find a minimum size set of nodes $S$ that power
dominates all the nodes, where a node $v$ is power dominated if (1) $v$ is in
$S$ or it has a neighbor in $S$, or (2) $v$ has a neighbor $u$ such that $u$
and all of its neighbors except $v$ are power dominated. Note that rule (1) is
the same as for the \textsc{Dominating Set} problem, and that rule (2) is a
type of propagation rule that applies iteratively. The $\ell$-round PDS problem
has the same set of rules as PDS, except we apply rule (2) in ``parallel'' in
at most $\ell-1$ rounds. We prove that $\ell$-round PDS cannot be approximated
better than $2^{\log^{1-\epsilon}{n}}$ even for $\ell=4$ in general graphs. We
provide a dynamic programming algorithm to solve $\ell$-round PDS optimally in
polynomial time on graphs of bounded tree-width. We present a PTAS (polynomial
time approximation scheme) for $\ell$-round PDS on planar graphs for
$\ell=O(\tfrac{\log{n}}{\log{\log{n}}})$. Finally, we give integer programming
formulations for $\ell$-round PDS.


title:
Global Existence and Uniqueness of Weak Solutions of 3-D Euler Equations
  with Helical Symmetry in the Absence of Vorticity Stretching

abstract:
  We prove uniqueness and existence of the weak solutions of Euler equations
with helical symmetry, with initial vorticity in $L^{\infty}$ under "no
vorticity stretching" geometric constraint. Our article follows the argument of
the seminal work of Yudovich. We adjust the argument to resolve the
difficulties which are specific to the helical symmetry.


title:
Bell inequality violation versus entanglement in presence of local
  decoherence

abstract:
  We analyze the effect of local decoherence of two qubits on their
entanglement and the Bell inequality violation. Decoherence is described by
Kraus operators, which take into account dephasing and energy relaxation at an
arbitrary temperature.
  We show that in the experiments with superconducting phase qubits the
survival time for entanglement should be much longer than for the Bell
inequality violation.


title: Logarithmic vector fields along smooth divisors in projective spaces

abstract:
  We show that a smooth divisor in a projective space can be reconstructed from
the isomorphism class of the sheaf of logarithmic vector fields along it if and
only if its defining equation is of Sebastiani-Thom type.


title: Minimizing the Maximum Interference is Hard

abstract:
  We consider the following interference model for wireless sensor and ad hoc
networks: the receiver interference of a node is the number of transmission
ranges it lies in. We model transmission ranges as disks. For this case we show
that choosing transmission radii which minimize the maximum interference while
maintaining a connected symmetric communication graph is NP-complete.


title:
Reply to the Comment on "Correlation between Dynamic Heterogeneity and
  Medium-Range Order in Two-Dimensional Glass-Forming Liquids"

abstract:
  This is our reply to the comment by Sausset and Tarjus (arXiv:0802.1631) on
our paper titled "Correlation between Dynamic Heterogeneity and Medium-Range
Order in Two-Dimensional Glass-Forming Liquids" [Phys. Rev. Lett. Vol. 99, No.
21, 215701 (2007)].


title:
Large Cross-phase Modulation Based on Double EIT in a Four-level Tripod
  Atomic System

abstract:
  We report the experimental observations on the simultaneous EIT effects for
probe and trigger fields (double EIT) as well as the large cross-phase
modulation (XPM) between the two fields in a four-level tripod EIT system of
the D1 line of 87Rb atoms. The XPM coefficients (larger than 2*10-5cm2/W) and
the accompanying transmissions (higher than 60%) are measured at slightly
detuning of the probe field from the exact EIT resonance condition. The
presented system can be applied in the recently proposed quantum information
processing with weak cross-Kerr nonlinearities.


title: Einstein solvmanifolds and the pre-Einstein derivation

abstract:
  An Einstein nilradical is a nilpotent Lie algebra, which can be the
nilradical of a metric Einstein solvable Lie algebra. The classification of
Riemannian Einstein solvmanifolds (possibly, of all noncompact homogeneous
Einstein spaces) can be reduced to determining, which nilpotent Lie algebras
are Einstein nilradicals and to finding, for every Einstein nilradical, its
Einstein metric solvable extension. For every nilpotent Lie algebra, we
construct an (essentially unique) derivation, the pre-Einstein derivation, the
solvable extension by which may carry an Einstein inner product. Using the
pre-Einstein derivation, we then give a variational characterization of
Einstein nilradicals. As an application, we prove an easy-to-check convex
geometry condition for a nilpotent Lie algebra with a nice basis to be an
Einstein nilradical and also show that a typical two-step nilpotent Lie algebra
is an Einstein nilradical.


title: Support Vector classifiers for Land Cover Classification

abstract:
  Support vector machines represent a promising development in machine learning
research that is not widely used within the remote sensing community. This
paper reports the results of Multispectral(Landsat-7 ETM+) and Hyperspectral
DAIS)data in which multi-class SVMs are compared with maximum likelihood and
artificial neural network methods in terms of classification accuracy. Our
results show that the SVM achieves a higher level of classification accuracy
than either the maximum likelihood or the neural classifier, and that the
support vector machine can be used with small training datasets and
high-dimensional data.


title: Jacobi forms of degree one

abstract:
  We show that a certain subspace of space of elliptic cusp forms is isomorphic
as a Hecke module to a certain subspace of space of Jacobi cusp forms of degree
one with matrix index by constructing an explicit lifting. This is a partial
generalization of the work of Skoruppa and Zagier. This lifting is also related
with the Ikeda lifting.


title: Channel-Width Dependent Enhancement in Nanoscale Field Effect Transistor

abstract:
  We report the observation of channel-width dependent enhancement in nanoscale
field effect transistors containing lithographically-patterned silicon
nanowires as the conduction channel. These devices behave as conventional
metal-oxide-semiconductor field-effect transistors in reverse source drain
bias. Reduction of nanowire width below 200 nm leads to dramatic change in the
threshold voltage. Due to increased surface-to-volume ratio, these devices show
higher transconductance per unit width at smaller width. Our devices with
nanoscale channel width demonstrate extreme sensitivity to surface field
profile, and therefore can be used as logic elements in computation and as
ultrasensitive sensors of surface-charge in chemical and biological species.


title:
Magnetocapacitive La0.6Sr0.4MnO3 0.7Pb(Mg0.33Nb0.67)O3 0.3PbTiO3
  epitaxial heterostructures

abstract:
  Epitaxial heterostructures of La0.6Sr0.4MnO3 0.7Pb(Mg0.33Nb0.67)O3 0.3PbTiO3
were fabricated on LaNiO3 coated LaAlO3 (100) substrates by pulsed laser
ablation. Ferromagnetic and ferroelectric hysteresis established their
biferroic nature. Dielectric behviour studied under different magnetic fields
over a wide range of frequency and temperatures revealed that the capacitance
in these heterostructures varies with the applied magnetic field. Appearance of
magnetocapacitance and its dependence on magnetic fields, magnetic layer
thickness, temperature and frequency indicated a combined contribution of
strain mediated magnetoelectric coupling, magnetoresistance of the magnetic
layer and Maxwell Wagner effect on the observed properties.


title: On local and global regularity of Fourier integral operators

abstract:
  The aim of this paper is to give a review of local and global properties of
Fourier integral operators with real and complex phases, in local $L^p$, global
$L^2$, and in Colombeau's spaces.


title: Janus and Multifaced Supersymmetric Theories

abstract:
  We investigate the various properties Janus supersymmetric Yang-Mills
theories. A novel vacuum structure is found and BPS monopoles and dyons are
studied. Less supersymmetric Janus theories found before are derived by a
simpler method. In addition, we find the supersymmetric theories when the
coupling constant depends on two and three spatial coordinates.


title:
Modeling friction on a mesoscale: Master equation for the
  earthquake-like model

abstract:
  The earthquake-like model with a continuous distribution of static thresholds
is used to describe the properties of solid friction. The evolution of the
model is reduced to a master equation which can be solved analytically. This
approach naturally describes stick-slip and smooth sliding regimes of
tribological systems within a framework which separates the calculation of the
friction force from the studies of the properties of the contacts.


title: Stabilization of Heegaard splittings

abstract:
  For each g greater than one there is a 3-manifold with two genus g Heegaard
splittings that require g stabilizations to become equivalent. Previously known
examples required at most one stabilization. Control of families of Heegaard
surfaces is obtained through a deformation to harmonic maps.


title:
Global $SO(3)\times SO(3)\times U(1)$ symmetry of the Hubbard model on
  bipartite lattices

abstract:
  It is found that for on-site interaction $U\neq 0$ the local $SU(2)\times
SU(2) \times U(1)$ gauge symmetry of the Hubbard model on a bipartite lattice
with vanishing transfer integral $t=0$ can be lifted to a global $[SU(2)\times
SU(2)\times U(1)]/Z_2^2=SO(3)\times SO(3)\times U(1)$ symmetry in the presence
of the kinetic-energy hopping term of the Hamiltonian with $t>0$. The generator
of the new found hidden independent charge global U(1) symmetry is one half the
rotated-electron number of singly-occupied sites operator. It is confirmed
elsewhere that our results have important physical consequences concerning the
further understanding of the unusual properties of the hole-doped cuprates.


title: Moduli of representations of quivers

abstract:
  An introduction to moduli spaces of representations of quivers is given, and
results on their global geometric properties are surveyed. In particular, the
geometric approach to the problem of classification of quiver representations
is motivated, and the construction of moduli spaces is reviewed. Topological,
arithmetic and algebraic methods for the study of moduli spaces are discussed.


title: Electromagnetic response of unconventional superconductors

abstract:
  We derive the current response to the linearly polarized electromagnetic
field with finite frequency and wave vector incident normally on the specular
surface of a clean nonconventional superconductor with orbital spontaneous
magnetization parallel to the crystal axis and perpendicular to the crystal
surface. The result includes the usual part known from the theory of
conventional superconductivity and as well the magneto-optical term typical for
the superconductors with spontaneous time reversal breaking. As an application
of the basic current-field relation we consider the Kerr effect for the
rotation of polarization of infrared light reflected from the superconductor
surface.


title: Goos-H\"{a}nchen-Like Shifts in Atom Optics

abstract:
  We consider the propagation of a matter wavepacket of two-level atoms through
a square potential created by a super-Gaussian laser beam. We explore the
matter wave analog of Goos-H\"{a}nchen shift within the framework of atom
optics where the roles of atom and light is exchanged with respect to
conventional optics. Using a vector theory, where atoms are treated as
particles possessing two internal spin components, we show that not only large
negative but also large positive Goos-H\"{a}nchen shifts can occur in the
reflected atomic beam.


title:
Pressure-induced unconventional superconductivity in the heavy-fermion
  antiferromagnet CeIn3: An 115In-NQR study under pressure

abstract:
  We report on the pressure-induced unconventional superconductivity in the
heavy-fermion antiferromagnet CeIn3 by means of nuclear-quadrupole-resonance
(NQR) studies conducted under a high pressure. The temperature and pressure
dependences of the NQR spectra have revealed a first-order quantum-phase
transition (QPT) from an AFM to PM at a critical pressure Pc=2.46 GPa. Despite
the lack of an AFM quantum critical point in the P-T phase diagram, we
highlight the fact that the unconventional SC occurs in both phases of the AFM
and PM. The nuclear spin-lattice relaxation rate 1/T1 in the AFM phase have
provided evidence for the uniformly coexisting AFM+SC phase. In the HF-PM phase
where AFM fluctuations are not developed, 1/T1 decreases without the coherence
peak just below Tc, followed by a power-law like T dependence that indicates an
unconventional SC with a line-node gap. Remarkably, Tc has a peak around Pc in
the HF-PM phase as well as in the AFM phase. In other words, an SC dome exists
with a maximum value of Tc = 230 mK around Pc, indicating that the origin of
the pressure-induced HF SC in CeIn3 is not relevant to AFM spin fluctuations
but to the emergence of the first-order QPT in CeIn3. When the AFM critical
temperature is suppressed at the termination point of the first-order QPT, Pc =
2.46 GPa, the diverging AFM spin-density fluctuations emerge at the critical
point from the AFM to PM. The results with CeIn3 leading to a new type of
quantum criticality deserve further theoretical investigations.


title: Local Thermal Equilibrium States and Quantum Energy Inequalities

abstract:
  In this paper we investigate the energy distribution of states of a linear
scalar quantum field with arbitrary curvature coupling on a curved spacetime
which fulfill some local thermality condition. We find that this condition
implies a quantum energy inequality for these states, where the (lower) energy
bounds depend only on the local temperature distribution and are local and
covariant (the dependence of the bounds other than on temperature is on
parameters defining the quantum field model, and on local quantities
constructed from the spacetime metric). Moreover, we also establish the
averaged null energy condition (ANEC) for such locally thermal states, under
growth conditions on their local temperature and under conditions on the free
parameters entering the definition of the renormalized stress-energy tensor.
These results hold for a range of curvature couplings including the cases of
conformally coupled and minimally coupled scalar field.


title:
Ruppeiner geometry and 2D dilaton gravity in the thermodynamics of black
  holes

abstract:
  We resolve the controversial issue of the geometric approach to the black
hole thermodynamics. The geometric description of the equilibrium
thermodynamics comes from Ruppeiner geometry based on a metric on the
thermodynamic state space. For this purpose, we consider the
Reissner-Nordstr\"om-AdS (RN-AdS) black hole which provides two different
ensembles: canonical ensemble for fixed-charge case and grand canonical
ensemble for fixed-potential case. Two cases are independent and cannot be
mixed into each other. Hence, we calculate different Ruppeiner curvatures for
two ensembles. However, we could not find the consistent behaviors of Ruppeiner
curvature corresponding to those of heat capacity. Alternatively, instead of
the Ruppeiner curvature, we newly propose the curvature scalar in the 2D
dilaton gravity approach which shows the features of extremal, Davies and
minimum temperature points of RN-AdS black hole, clearly.


title:
Quantitative analysis of electronic transport through weakly-coupled
  metal/organic interfaces

abstract:
  Using single-crystal transistors, we have performed a systematic experimental
study of electronic transport through oxidized copper/rubrene interfaces as a
function of temperature and bias. We find that the measurements can be
reproduced quantitatively in terms of the thermionic emission theory for
Schottky diodes, if the effect of the bias-induced barrier lowering is
included. Our analysis emphasizes the role of the coupling between metal and
molecules, which in our devices is weak due to the presence of an oxide layer
at the surface of the copper electrodes.


title:
Quantum information processing with single photons and atomic ensembles
  in microwave coplanar waveguide resonators

abstract:
  We show that pairs of atoms optically excited to the Rydberg states can
strongly interact with each other via effective long-range dipole-dipole or van
der Waals interactions mediated by their non-resonant coupling to a common
microwave field mode of a superconducting coplanar waveguide cavity. These
cavity mediated interactions can be employed to generate single photons and to
realize in a scalable configuration a universal phase gate between pairs of
single photon pulses propagating or stored in atomic ensembles in the regime of
electromagnetically induced transparency.


title:
A New Approach of Point Estimation from Truncated or Grouped and
  Censored Data

abstract:
  We propose a new approach for estimating the parameters of a probability
distribution. It consists on combining two new methods of estimation. The first
is based on the definition of a new distance measuring the difference between
variations of two distributions on a finite number of points from their support
and on using this measure for estimation purposes by the method of minimum
distance. For the second method, given an empirical discrete distribution, we
build up an auxiliary discrete theoretical distribution having the same support
of the first and depending on the same parameters of the parent distribution of
the data from which the empirical distribution emanated. We estimate then the
parameters from the empirical distribution by the usual statistical methods. In
practice, we propose to compute the two estimations, the second based on
maximum likelihood principle of known theoretical properties, and the first
being as a control of the effectiveness of the obtained estimation, and for
which we prove the convergence in probability, so we have also a criterion on
the quality of the information contained in the observations. We apply the
approach to truncated or grouped and censored data situations to give the
flavour on the effectiveness of the approach. We give also some interesting
perspectives of the approach including model selection from truncated data,
estimation of the initial trial value in the celebrate EM algorithm in the case
of truncation and merged normal populations, a test of goodness of fit based on
the new distance, quality of estimations and data.


title: Teleportation using continuous variable quantum cloning machine

abstract:
  We show that an unknown quantum state in phase space can be teleported via
three-mode entanglement generated by continuous variable quantum cloning
machine (transformation). Further, proceeding with our teleportation protocol
we are able to improve the fidelity of teleportation obtained by Loock et.al.
[Phys.Rev.Lett. 84, 3482(2000)]. Also we study here the entanglement between
the two output copies from cloning machine.


title: Choice numbers of graphs

abstract:
  A solution to a problem of Erd\H{o}s, Rubin and Taylor is obtained by showing
that if a graph $G$ is $(a:b)$-choosable, and $c/d > a/b$, then $G$ is not
necessarily $(c:d)$-choosable. The simplest case of another problem, stated by
the same authors, is settled, proving that every 2-choosable graph is also
$(4:2)$-choosable. Applying probabilistic methods, an upper bound for the
$k^{th}$ choice number of a graph is given. We also prove that a directed graph
with maximum outdegree $d$ and no odd directed cycle is $(k(d+1):k)$-choosable
for every $k \geq 1$. Other results presented in this article are related to
the strong choice number of graphs (a generalization of the strong chromatic
number). We conclude with complexity analysis of some decision problems related
to graph choosability.


title:
A Radar-Shaped Statistic for Testing and Visualizing Uniformity
  Properties in Computer Experiments

abstract:
  In the study of computer codes, filling space as uniformly as possible is
important to describe the complexity of the investigated phenomenon. However,
this property is not conserved by reducing the dimension. Some numeric
experiment designs are conceived in this sense as Latin hypercubes or
orthogonal arrays, but they consider only the projections onto the axes or the
coordinate planes. In this article we introduce a statistic which allows
studying the good distribution of points according to all 1-dimensional
projections. By angularly scanning the domain, we obtain a radar type
representation, allowing the uniformity defects of a design to be identified
with respect to its projections onto straight lines. The advantages of this new
tool are demonstrated on usual examples of space-filling designs (SFD) and a
global statistic independent of the angle of rotation is studied.


title:
A Distributed Merge and Split Algorithm for Fair Cooperation in Wireless
  Networks

abstract:
  This paper introduces a novel concept from coalitional game theory which
allows the dynamic formation of coalitions among wireless nodes. A simple and
distributed merge and split algorithm for coalition formation is constructed.
This algorithm is applied to study the gains resulting from the cooperation
among single antenna transmitters for virtual MIMO formation. The aim is to
find an ultimate transmitters coalition structure that allows cooperating users
to maximize their utilities while accounting for the cost of coalition
formation. Through this novel game theoretical framework, the wireless network
transmitters are able to self-organize and form a structured network composed
of disjoint stable coalitions. Simulation results show that the proposed
algorithm can improve the average individual user utility by 26.4% as well as
cope with the mobility of the distributed users.


title: Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS

abstract:
  The measurements of the Collins and Sivers asymmetries of identified hadrons
produced in deep-inelastic scattering of 160 GeV/c muons on a transversely
polarised 6LiD target at COMPASS are presented. The results for charged pions
and charged and neutral kaons correspond to all data available, which were
collected from 2002 to 2004. For all final state particles both the Collins and
Sivers asymmetries turn out to be small, compatible with zero within the
statistical errors, in line with the previously published results for not
identified charged hadrons, and with the expected cancellation between the u-
and d-quark contributions.


title:
Weak Dispersive estimates for Schr\"odinger equations with long range
  potentials

abstract:
  We prove some local smoothing estimates for the Schr\"{o}dinger initial value
problem with data in $L^2(\mathbb{R}^d)$, $d \geq 2$ and a general class of
potentials. In the repulsive setting we have to assume just a power like decay
$(1+|x|)^{-\gamma}$ for some $\gamma>0$. Also attractive perturbations are
considered. The estimates hold for all time and as a consequence a weak
dispersion of the solution is obtained. The proofs are based on similar
estimates for the corresponding stationary Helmholtz equation and Kato H-smooth
theory.


title: Probing two Universal Extra Dimensions at International Linear Collider

abstract:
  We discuss collider signatures of (1,1)-th Kaluza-Klein (KK) mode vector
bosons in the framework of two universal extra dimension model, at a future
electron-positron collider. Production of the (1,1)-th KK mode of electro-weak
vector bosons (B(1,1), W3(1,1)), are considered in association with a hard
photon. Without caring about the decay products of those vector bosons, one can
measure the masses of these particles just by looking at the photon energy
distribution. Once produced these particles dominantly decay to a pair of jets
or to a pair of top quarks. Thus we look for a pair of jets or a pair of top
quarks in association with a photon. Upto the kinematic limit of the collider,
signals from the B(1,1) production and decay in both the above mentioned
channels are greater than the $5\sigma$ fluctuation of the Standard Model
background. However, the number of events from W3(1,1) production and decay is
smaller and its detection prospect is not very good.


title: Gray identities, canonical connection and integrability

abstract:
  We characterize quasi K\"ahler manifolds whose curvature tensor associated to
the canonical Hermitian connection satisfies the first Bianchi identity. This
condition is related with the third Gray identity and in the almost K\"ahler
case implies the integrability. Our main tool is the existence of generalized
holomorphic frames introduced by the second author previously. By using such
frames we also give a simpler and shorter proof of a Theorem of Goldberg.
Furthermore we study almost Hermitian structures having the curvature tensor
associated to the canonical Hermitian connection equal to zero. We show some
explicit examples of quasi K\"ahler structures on the Iwasawa manifold having
the Hermitian curvature vanishing and the Riemann curvature tensor satisfying
the second Gray identity.


title:
Could dark matter or neutrinos discriminate between the enantiomers of a
  chiral molecule?

abstract:
  We examine the effect of cold dark matter on the discrimination between the
two enantiomers of a chiral molecule. We estimate the energy difference between
the two enantiomers due to the interaction between fermionic WIMPs (weak
interacting massive particles) and molecular electrons on the basis that
electrons have opposite helicities in opposite enantiomers. It is found that
this energy difference is completely negligible. Dark matter could then be
discarded as an inductor of chiroselection between enantiomers and then of
biological homochirality. However, the effect of cosmological neutrinos,
revisited with the currently accepted neutrino density, would reach, in the
most favorable case, an upper bound of the same order of magnitude as the
energy difference obtained from the well known electroweak electron-nucleus
interaction in some molecules.


title: Stability of PID-Controlled Linear Time-Delay Feedback Systems

abstract:
  The stability of feedback systems consisting of linear time-delay plants and
PID controllers has been investigated for many years by means of several
methods, of which the Nyquist criterion, a generalization of the
Hermite-Biehler Theorem, and the root location method are well known. The main
purpose of these researches is to determine the range of controller parameters
that allow stability. Explicit and complete expressions of the boundaries of
these regions and computation procedures with a finite number of steps are now
available only for first-order plants, provided with one time delay. In this
note, the same results, based on Pontryagin's studies, are presented for
arbitrary-order plants.


title: Schwarzian derivative and Numata Finsler structures

abstract:
  The flag curvature of the Numata Finsler structures is shown to admit a
nontrivial prolongation to the one-dimensional case, revealing an unexpected
link with the Schwarzian derivative of the diffeomorphisms associated with
these Finsler structures.


title:
Thermodynamic and transport anomalies near isotropic-nematic phase
  transition

abstract:
  A theoretical study of the variation of thermodynamic and transport
properties of calamitic liquid crystals across the isotropic-nematic phase
transition is carried out by calculating the {\it wavenumber (k) and time (t)}
dependent intermediate scattering function of the liquid, via computer
simulations of model nematogens. The objective is to understand the
experimentally observed anomalies and sharp variation in many thermodynamic and
transport properties, namely specific heat $C$, sound attenuation coefficient
$\Gamma$, thermal diffusivity $D_T$ and sound velocity $c_s$ are as the I-N
transition is approached from the isotropic side. The small wavelength limit of
the calculated intermediate scattering function $F(k,t)$ is used to obtain the
ratio of specific heats $\gamma$ and other properties mentioned above. We find
that all of them show non-monotonic variations near the I-N transition, with
$\Gamma$ showing a cusp-like behavior. We suggest that the observed anomalous
features are a direct consequence of the existence of pseudo-nematic domains in
the system near the phase boundary and the melting and formation of such
domains give rise to sound attenuation and also to the observed specific heat
anomaly. A theoretical description of these anomalies should invoke
translation-rotation coupling at molecular level. While the heterogeneous
dynamics observed here bear resemblance to that in deeply supercooled liquids
near glass transition, the thermodynamic anomalies articulated here are largely
absent in supercooled liquids.


title: Constrained MaxLik reconstruction of multimode photon distributions

abstract:
  We address the reconstruction of the full photon distribution of multimode
fields generated by seeded parametric down-conversion (PDC). Our scheme is
based on on/off avalanche photodetection assisted by maximum-likelihood
(MaxLik) estimation and does not involve photon counting. We present a novel
constrained MaxLik method that incorporates the request of finite energy to
improve the rate of convergence and, in turn, the overall accuracy of the
reconstruction.


title:
Evaluating measures of nonclassical correlation in a multipartite
  quantum system

abstract:
  We introduce and compare several measures of nonclassical correlation defined
on the basis of a widely-recognized paradigm claiming that a multipartite
system represented by a density matrix having no product eigenbasis possesses
nonclassical correlation.


title: Solar wind speed theory and the nonextensivity of solar corona

abstract:
  The solar corona is a complex system, with nonisothermal plasma and being in
the self-gravitating field of the Sun. So the corona plasma is not only a
nonequilibrium system but also a nonextensive one. We estimate the parameter of
describing the degree of nonextensivity of the corona plasma and study the
generalization of the solar wind speed theory in the framework of nonextensive
statistical mechanics. It is found that, when use Chapman's corona model (1957)
as the radial distribution of the temperature in the corona, the nonextensivity
reduces the gas pressure outward and thus leads a significant deceleration
effect on the radial speed of the solar wind.


title: Meta-stability and condensed zero-range processes on finite sets

abstract:
  We propose a definition o meta-stability and obtain sufficient conditions for
a sequence of Markov processes on finite state spaces to be meta-stable. In the
reversible case, these conditions reduce to estimates of the capacity and the
measure of certain meta-stable sets. We prove that a class of condensed
zero-range processes with asymptotically decreasing jump rates is meta-stable.


title:
Reflected backward stochastic differential equations and a class of non
  linear dynamic pricing rule

abstract:
  In that paper, we provide a new characterization of the solutions of specific
reflected backward stochastic differential equations (or RBSDEs) whose driver
$g$ is convex and has quadratic growth in its second variable: this is done by
introducing the extended notion of $g$-Snell enveloppe. Then, in a second step,
we relate this representation to a specific class of dynamic monetary concave
functionals already introduced in a discrete time setting. This connection
implies that the solution, characterized by means of non linear expectations,
has again the time consistency property.


title: Wilson-Polyakov surfaces and M-theory branes

abstract:
  In this paper, we study the M-brane description of the Wilson-Polyakov
surfaces in six-dimensional (2, 0) field theory at finite temperature. We
investigate the membrane solution dual to a straight Wilons-Polyakov surface
and compute the interaction potential between two parallel straight strings by
using AdS/CFT correspondence. Furthermore we discuss the M5-brane solutions
dual to various Wilson-Polyakov surfaces. Finally we obtain an universal result
about M5-brane solutions in generic backgrounds.


title: First catalog of strong lens candidates in the COSMOS field

abstract:
  We present the first catalog of 67 strong galaxy-galaxy lens candidates
discovered in the 1.64 square degree Hubble Space Telescope COSMOS survey.
Twenty of these systems display multiple images or strongly curved large arcs.
Our initial search is performed by visual inspection of the data and is
restricted, for practical considerations, to massive early-type lens galaxies
with arcs found at radii smaller than ~5''. Simple mass models are constructed
for the best lens candidates and our results are compared to the strong lensing
catalogs of the SLACS survey and the CASTLES database. These new strong
galaxy-galaxy lensing systems constitute a valuable sample to study the mass
distribution of early-type galaxies and their associated dark matter halos. We
further expect this sample to play an important role in the testing of software
algorithms designed to automatically search for strong gravitational lenses.
  From our analysis a robust lower limit is derived for the expected occurrence
of strong galaxy-galaxy systems in current and future space-based wide-field
imaging surveys. We expect that such surveys should uncover a large number of
strong lensing systems (more than 10 systems per square degree), which will
allow for a detailed statistical analysis of galaxy properties and will likely
lead to constraints on models of gravitational structure formation and
cosmology. The sample of strong lenses is available here:
http://cosmosstronglensing.uni-hd.de/


title: Bounds on the Number of Numerical Semigroups of a Given Genus

abstract:
  Combinatorics on multisets is used to deduce new upper and lower bounds on
the number of numerical semigroups of each given genus, significantly improving
existing ones. In particular, it is proved that the number $n_g$ of numerical
semigroups of genus $g$ satisfies $2F_{g}\leq n_g\leq 1+3\cdot 2^{g-3}$, where
$F_g$ denotes the $g$th Fibonacci number.


title: Noncommutative Schwarzschild Black Hole and Area Law

abstract:
  Using a graphical analysis, we show that for the horizon radius $r_h\gtrsim
4.8\sqrt\theta$, the standard semiclassical Bekenstein-Hawking area law for
noncommutative Schwarzschild black hole exactly holds for all orders of
$\theta$. We also give the corrections to the area law to get the exact nature
of the Bekenstein-Hawking entropy when $r_h<4.8\sqrt\theta$ till the extremal
point $r_h=3.0\sqrt{\theta}$.


title: Center-to-Limb Variation of Solar 3-D Hydrodynamical Simulations

abstract:
  We examine closely the solar Center-to-Limb variation of continua and lines
and compare observations with predictions from both a 3-D hydrodynamic
simulation of the solar surface (provided by M. Asplund and collaborators) and
1-D model atmospheres. Intensities from the 3-D time series are derived by
means of the new synthesis code ASSET, which overcomes limitations of
previously available codes by including a consistent treatment of scattering
and allowing for arbitrarily complex line and continuum opacities. In the
continuum, we find very similar discrepancies between synthesis and observation
for both types of model atmospheres. This is in contrast to previous studies
that used a ``horizontally'' and time averaged representation of the 3-D model
and found a significantly larger disagreement with observations. The presence
of temperature and velocity fields in the 3-D simulation provides a significant
advantage when it comes to reproduce solar spectral line shapes. Nonetheless, a
comparison of observed and synthetic equivalent widths reveals that the 3-D
model also predicts more uniform abundances as a function of position angle on
the disk. We conclude that the 3-D simulation provides not only a more
realistic description of the gas dynamics, but, despite its simplified
treatment of the radiation transport, it also predicts reasonably well the
observed Center-to-Limb variation, which is indicative of a thermal structure
free from significant systematic errors.


title: Geographical dispersal of mobile communication networks

abstract:
  In this paper, we analyze statistical properties of a communication network
constructed from the records of a mobile phone company. The network consists of
2.5 million customers that have placed 810 millions of communications (phone
calls and text messages) over a period of 6 months and for whom we have
geographical home localization information. It is shown that the degree
distribution in this network has a power-law degree distribution $k^{-5}$ and
that the probability that two customers are connected by a link follows a
gravity model, i.e. decreases like $d^{-2}$, where $d$ is the distance between
the customers. We also consider the geographical extension of communication
triangles and we show that communication triangles are not only composed of
geographically adjacent nodes but that they may extend over large distances.
This last property is not captured by the existing models of geographical
networks and in a last section we propose a new model that reproduces the
observed property. Our model, which is based on the migration and on the local
adaptation of agents, is then studied analytically and the resulting
predictions are confirmed by computer simulations.


title:
Colors and Mass-to-Light Ratios of Bulges and Disks of Nearby Spiral
  Galaxies

abstract:
  We investigate colors and mass-to-light ratios ($M/L$s) of the bulges and
disks for 28 nearby spiral galaxies with various morphological types of Sab to
Scd, using images in optical and near-infrared ($V$, $I$, and $J$) bands and
published rotation curves. It is shown that the observed colors and $M/L$s
generally agree with the galaxy formation model with an exponentially declining
star formation rate and shallow slope (ex. Scalo) initial mass function (IMF)
for both the bulges and the disks. We find that the bulge $M/L$ is generally
higher than the disk $M/L$ and that the galaxies with larger bulge-to-total
luminosity ratio tend to have a smaller bulge $M/L$. The fact indicates that
the luminosity-weighted average age of bulges for early-type spirals is younger
than that of later-type spirals. These results support a formation scenario
that produces young stars for the bulges of middle-type and early-type spirals.


title: Mean field theory of hard sphere glasses and jamming

abstract:
  Hard spheres are ubiquitous in condensed matter: they have been used as
models for liquids, crystals, colloidal systems, granular systems, and powders.
Packings of hard spheres are of even wider interest, as they are related to
important problems in information theory, such as digitalization of signals,
error correcting codes, and optimization problems. In three dimensions the
densest packing of identical hard spheres has been proven to be the FCC
lattice, and it is conjectured that the closest packing is ordered (a regular
lattice, e.g, a crystal) in low enough dimension. Still, amorphous packings
have attracted a lot of interest, because for polydisperse colloids and
granular materials the crystalline state is not obtained in experiments for
kinetic reasons. We review here a theory of amorphous packings, and more
generally glassy states, of hard spheres that is based on the replica method:
this theory gives predictions on the structure and thermodynamics of these
states. In dimensions between two and six these predictions can be successfully
compared with numerical simulations. We will also discuss the limit of large
dimension where an exact solution is possible. Some of the results we present
here have been already published, but others are original: in particular we
improved the discussion of the large dimension limit and we obtained new
results on the correlation function and the contact force distribution in three
dimensions. We also try here to clarify the main assumptions that are beyond
our theory and in particular the relation between our static computation and
the dynamical procedures used to construct amorphous packings.


title:
The Milagro anticenter hot spots: cosmic rays from the Geminga supernova
  ?

abstract:
  The Milagro experiment has announced the discovery of an excess flux of TeV
cosmic rays from the general direction of the heliotail, also close to the
Galactic anticenter. We investigate the hypothesis that the excess cosmic rays
were produced in the SN explosion that gave birth to the Geminga pulsar. The
assumptions underlying our proposed scenario are that the Geminga supernova
occurred about 3.4 10^5 years ago (as indicated by the spin down timescale),
that a burst of cosmic rays was injected with total energy 10^49 erg (i.e.,
about 1% of a typical SN output), and that the Geminga pulsar was born with a
positive radial velocity of 100--200 km s^-1. We find that our hypothesis is
consistent with the available information. In a first variant (likely
oversimplified), the cosmic rays have diffused according to the Bohm
prescription (i.e., with a diffusion coefficient on the order of c times r_L,
with c the speed of light and r_L the Larmor radius). An alternative scheme
assumes that diffusion only occurred initially, and the final propagation to
the Sun was a free streaming in a diverging magnetic field. If the observed
cosmic ray excess does indeed arise from the Geminga SN explosion, the
long--sought "smoking gun" connecting cosmic rays with supernovae would finally
be at hand. It could be said that, while looking for the "smoking gun", we were
hit by the bullets themselves.


title:
Gauge invariant sub-structures of tree-level double-emission exact QCD
  spin amplitudes

abstract:
  In this note we discuss possible separations of exact, massive, tree-level
spin amplitudes into gauge invariant parts. We concentrate our attention on
processes involving two quarks entering a color- neutral current and, thanks to
the QCD interactions, two extra external gluons. We will search for forms
compatible with parton shower languages, without applying approximations or
restrictions on phase space regions. Special emphasis will be put on the
isolation of parts necessary for the construction of evolution kernels for
individual splittings and to some degree for the running coupling constant as
well. Our aim is to better understand the environment necessary to optimally
match hard matrix elements with partons shower algorithms. To avoid
complications and ambiguities related to regularization schemes, we ignore, at
this point, virtual corrections. Our representation is quite universal: any
color-neutral current can be used, in particular our approach is not restricted
to vector currents only.


title: Verification of Models for Calculation of E1 Radiative Strength

abstract:
  Photoabsorption cross sections and gamma-decay strength function are
calculated and compared with experimental data to test the existing models of
dipole radiative strength functions (RSF) for the middle-weight and heavy
atomic nuclei. Simplified version of the modified Lorentzian model are
proposed. New tables of giant dipole resonance (GDR) parameters are given. It
is shown that the phenomenological closed-form models with asymmetric shape can
be used for overall estimates of the dipole RSF in the gamma -ray energy region
up to about 20 MeV when GDR parameters are known or the GDR systematics can be
adopted. Otherwise, the HFB-QRPA microscopic model and the semi-classical
approach with moving surface appear to be more adequate methods to estimate the
dipole photoabsorption RSF.


title: Set Covering Problems with General Objective Functions

abstract:
  We introduce a parameterized version of set cover that generalizes several
previously studied problems. Given a ground set V and a collection of subsets
S_i of V, a feasible solution is a partition of V such that each subset of the
partition is included in one of the S_i. The problem involves maximizing the
mean subset size of the partition, where the mean is the generalized mean of
parameter p, taken over the elements. For p=-1, the problem is equivalent to
the classical minimum set cover problem. For p=0, it is equivalent to the
minimum entropy set cover problem, introduced by Halperin and Karp. For p=1,
the problem includes the maximum-edge clique partition problem as a special
case. We prove that the greedy algorithm simultaneously approximates the
problem within a factor of (p+1)^1/p for any p in R^+, and that this is the
best possible unless P=NP. These results both generalize and simplify previous
results for special cases. We also consider the corresponding graph coloring
problem, and prove several tractability and inapproximability results. Finally,
we consider a further generalization of the set cover problem in which we aim
at minimizing the sum of some concave function of the part sizes. As an
application, we derive an approximation ratio for a Rent-or-Buy set cover
problem.


title:
Production of Magnetic Turbulence by Cosmic Rays Drifting Upstream of
  Supernova Remnant Shocks

abstract:
  We present results of 2D and 3D PIC simulations of magnetic turbulence
production by isotropic cosmic-ray ions drifting upstream of SNR shocks. The
studies aim at testing recent predictions of a strong amplification of short
wavelength magnetic field and at studying the evolution of the magnetic
turbulence and its backreaction on cosmic rays. We observe that an oblique
filamentary mode grows more rapidly than the non-resonant parallel modes found
in analytical theory, and the growth rate of the field perturbations is much
slower than is estimated for the parallel plane-wave mode, possibly because in
our simulations we cannot maintain omega << Omega_i, the ion gyrofrequency, to
the degree required for the plane-wave mode to emerge. The evolved oblique
filamentary mode was also observed in MHD simulations to dominate in the
nonlinear phase. We thus confirm the generation of the turbulent magnetic field
due to the drift of cosmic-ray ions in the upstream plasma, but as our main
result find that the amplitude of the turbulence saturates at about dB/B~1. The
backreaction of the turbulence on the particles leads to an alignment of the
bulk-flow velocities of the cosmic rays and the background medium, which is an
essential characteristic of cosmic-ray modified shocks. It accounts for the
saturation of the instability at moderate field amplitudes. Previously
published MHD simulations have assumed a constant cosmic-ray current and no
energy or momentum flux in the cosmic rays, which excludes a backreaction of
the generated magnetic field on cosmic rays, and thus the saturation of the
field amplitude is artificially suppressed. This may explain the continued
growth of the magnetic field in the MHD simulations. A strong magnetic field
amplification to amplitudes dB >> B0 has not been demonstrated yet.


title:
Weak convergence of the supremum distance for supersmooth kernel
  deconvolution

abstract:
  We derive the asymptotic distribution of the supremum distance of the
deconvolution kernel density estimator to its expectation for certain
supersmooth deconvolution problems. It turns out that the asymptotics are
essentially different from the corresponding results for ordinary smooth
deconvolution.


title: General Notion of Curvature in Catastrophe Theory Terms

abstract:
  We introduce a new notion of a curvature of a superconnection, different from
the one obtained by a purely algebraic analogy with the curvature of a linear
connection. The naturalness of this new notion of a curvature of a
superconnection comes from the study of singularities of smooth sections of
vector bundles (Catastrophe Theory). We demonstrate that the classical examples
of obstructions to a local equivalence: exterior differential for 2-forms,
Riemannian tensor, Weil tensor, curvature of a linear connection and Nijenhuis
tensor can be treated in terms of one general approach. This approach, applied
to the superconnection leads to a new notion of a curvature (proposed in this
paper) of a superconnection.


title:
Quantum Mechanical Breakdown of Perfect Homogeneity in Reheating After
  Inflation

abstract:
  In the context of quantum fields in time dependent classical backgrounds, we
notice that the number of created particles with a given momentum largely
deviates about its mean value. Guided with this observation we use a complete
orthonormal family of localized wave packets to calculate the deviations in the
number and energy densities of particles produced in a volume of a given size
during reheating. It turns out that at the end of reheating there exists (in
general tiny) spatial variations in these densities on Hubble length scales
over which local interactions are incapable of restoring homogeneity. This
signals the destruction of perfect homogeneity attained after inflation due to
the quantum nature of particle production process in reheating.


title: Telescope conjecture, idempotent ideals, and the transfinite radical

abstract:
  We show that for an artin algebra $\Lambda$, the telescope conjecture for
module categories is equivalent to certain idempotent ideals of mod-$\Lambda$
being generated by identity morphisms. As a consequence, we prove the
conjecture for domestic standard selfinjective algebras and domestic special
biserial algebras. We achieve this by showing that in any Krull-Schmidt
category with local d.c.c. on ideals, any idempotent ideal is generated by
identity maps and maps from the transfinite radical.


title:
Wightman function and vacuum densities in de Sitter spacetime with
  toroidally compactified dimensions

abstract:
  We investigate the Wightman function, the vacuum expectation values of the
field square and the energy-momentum tensor for a scalar field with general
curvature coupling parameter in $(D+1)$-dimensional de Sitter spacetime with an
arbitrary number of compactified spatial dimensions. Both cases of periodicity
and antiperiodicity conditions along the compactified dimensions are
considered. Recurrence formulae are derived which express the vacuum
expectation values for the dS spacetime of topology $\mathrm{R}^{p}\times
(\mathrm{S}^{1})^{q}$ in the form of the sum of the vacuum expectation values
in the topology $\mathrm{R}^{p+1}\times (\mathrm{S}^{1})^{q-1}$ and the part
induced by the compactness of the $(p+1)$th spatial dimension. The behavior of
the topological parts is investigated in various asymptotic regions of the
parameters. In the early stages of the cosmological evolution the topological
parts dominate the contribution in the expectation values due to the
uncompactified dS part. In this limit the behavior of the topological parts
does not depend on the curvature coupling parameter and coincides with that for
a conformally coupled massless field. At late stages of the cosmological
expansion the expectation values are dominated by the part corresponding to
uncompactified dS spacetime. The vanishing of the topological parts is
monotonic or oscillatory in dependence of the mass and the curvature coupling
parameter of the field.


title: On the Invariant Theory of Weingarten Surfaces in Euclidean Space

abstract:
  We prove that any strongly regular Weingarten surface in Euclidean space
carries locally geometric principal parameters. The basic theorem states that
any strongly regular Weingarten surface is determined up to a motion by its
structural functions and the normal curvature function satisfying a geometric
differential equation. We apply these results to the special Weingarten
surfaces: minimal surfaces, surfaces of constant mean curvature and surfaces of
constant Gauss curvature.


title: Non-equilibrium polaron hopping transport through DNA

abstract:
  We study the electronic transport through short DNA chains with various
sequences of base pairs between voltage-biased leads. The strong coupling of
the charge carriers to local vibrations of the base pairs leads to the
formation of polarons, and in the relevant temperature range the transport is
accomplished by sequential polaron hopping. We calculate the rates for these
processes, extending what is known as the $P(E)$-theory of single-electron
tunneling to the situation with site-specific local oscillators. The
non-equilibrium charge rearrangement along the DNA leads to sequence-dependent
current thresholds of the `semi-conducting' current-voltage characteristics
and, except for symmetric sequences, to rectifying behavior. The current is
thermally activated with activation energy approaching for voltages above the
threshold the bulk value (polaron shift or reorganization energy). Our results
are consistent with some recent experiments.


title: Synchronization and Stability in Noisy Population Dynamics

abstract:
  We study the stability and synchronization of predator-prey populations
subjected to noise. The system is described by patches of local populations
coupled by migration and predation over a neighborhood. When a single patch is
considered, random perturbations tend to destabilize the populations, leading
to extinction. If the number of patches is small, stabilization in the presence
of noise is maintained at the expense of synchronization. As the number of
patches increases, both the stability and the synchrony among patches increase.
However, a residual asynchrony, large compared with the noise amplitude, seems
to persist even in the limit of infinite number of patches. Therefore, the
mechanism of stabilization by asynchrony recently proposed by R. Abta et. al.,
combining noise, diffusion and nonlinearities, seems to be more general than
first proposed.


title: DNA denaturation bubbles at criticality

abstract:
  The equilibrium statistical properties of DNA denaturation bubbles are
examined in detail within the framework of the Peyrard-Bishop-Dauxois model.
Bubble formation in homogeneous DNA is found to depend crucially on the
presence of nonlinear base-stacking interactions. Small bubbles extending over
less than 10 base pairs are associated with much larger free energies of
formation per site than larger bubbles. As the critical temperature is
approached, the free energy associated with further bubble growth becomes
vanishingly small. An analysis of average displacement profiles of bubbles of
varying sizes at different temperatures reveals almost identical scaled shapes
in the absence of nonlinear stacking; nonlinear stacking leads to distinct
scaled shapes of large and small bubbles.


title: Production of Secondaries in High Energy d+Au Collisions

abstract:
  In the framework of Quark-Gluon String Model we calculate the inclusive
spectra of secondaries produced in d+Au collisions at intermediate (CERN SPS)
and at much higher (RHIC) energies. The results of numerical calculations at
intermediate energies are in reasonable agreement with the data. At RHIC
energies numerically large inelastic screening corrections (percolation
effects) should be accounted for in calculations. We extract these effects from
the existing RHIC experimental data on minimum bias and central d+Au
collisions. The predictions for p+Au interactions at LHC energy are also given.


title: Arithmetic $\D$-modules and Representations

abstract:
  We propose in this paper an approach to Breuil's conjecture on a Langlands
correspondence between $p$-adic Galois representations and representations of
$p$-adic Lie groups in $p$-adic topological vector spaces. We suggest that
Berthelot's theory of arithmetic $D$-modules should give a $p$-adic analogue of
Kashiwara's theory of $D$-modules for real Lie groups i.e. it should give a
realization of the $p$-adic representations of a $p$-adic Lie group as spaces
of overconvergent solutions of arithmetic $D$-modules which will come equipped
with an action of the Galois group. We shall discuss the case of Siegel modular
varieties as a possible testing ground for the proposal.


title:
Deviations of Riesz projections of Hill operators with singular
  potentials

abstract:
  It is shown that the deviations $P_n -P_n^0$ of Riesz projections $$
  P_n = \frac{1}{2\pi i} \int_{C_n} (z-L)^{-1} dz, \quad C_n=\{|z-n^2|= n\}, $$
of Hill operators $L y = - y^{\prime \prime} + v(x) y, x \in [0,\pi],$ with
zero and $H^{-1}$ periodic potentials go to zero as $n \to \infty $ even if we
consider $P_n -P_n^0$ as operators from $L^1$ to $L^\infty. $ This implies that
all $L^p$-norms are uniformly equivalent on the Riesz subspaces $Ran P_n. $


title:
Quantum field theory in terms of consistency conditions I: General
  framework, and perturbation theory via Hochschild cohomology

abstract:
  In this paper, we propose a new framework for quantum field theory in terms
of consistency conditions. The consistency conditions that we consider are
"associativity" or "factorization" conditions on the operator product expansion
(OPE) of the theory, and are proposed to be the defining property of any
quantum field theory. Our framework is presented in the Euclidean setting, and
is applicable in principle to any quantum field theory, including non-conformal
ones. In our framework, we obtain a characterization of perturbations of a
given quantum field theory in terms of a certain cohomology ring of
Hochschild-type. We illustrate our framework by the free field, but our
constructions are general and apply also to interacting quantum field theories.
For such theories, we propose a new scheme to construct the OPE which is based
on the use of non-linear quantized field equations.


title:
Lorentz violating extension of the Standard Model and the Beta-decay
  end-point

abstract:
  The Standard Model extension with additional Lorentz violating terms allows
for redefining the equation of motion of a propagating left-handed fermionic
particle. The obtained Dirac-type equation can be embedded in a generalized
Lorentz-invariance preserving-algebra through the definition of Lorentz
algebra-like generators with a light-like preferred axis. The resulting
modification to the fermionic equation of motion introduces some novel
ingredients to the phenomenological analysis of the cross section of the
tritium $\beta$-decay. Assuming lepton number conservation, our formalism
provides a natural explanation for the tritium $\beta$-decay end-point via an
effective neutrino mass term without the need of a sterile right-handed state.


title: Multi-particle collision dynamics modeling of viscoelastic fluids

abstract:
  In order to investigate the rheological properties of viscoelastic fluids by
mesoscopic hydrodynamics methods, we develop a multi-particle collision
dynamics (MPC) model for a fluid of harmonic dumbbells. The algorithm consists
of alternating streaming and collision steps. The advantage of the harmonic
interactions is that the integration of the equations of motion in the
streaming step can be performed analytically. Therefore, the algorithm is
computationally as efficient as the original MPC algorithm for Newtonian
fluids. The collision step is the same as in the original MPC method. All
particles are confined between two solid walls moving oppositely, so that both
steady and oscillatory shear flows can be investigated. Attractive wall
potentials are applied to obtain a nearly uniform density everywhere in the
simulation box. We find that both in steady and oscillatory shear flow, a
boundary layer develops near the wall, with a higher velocity gradient than in
the bulk. The thickness of this layer is proportional to the average dumbbell
size. We determine the zero-shear viscosities as a function of the spring
constant of the dumbbells and the mean free path. For very high shear rates, a
very weak ``shear thickening'' behavior is observed. Moreover, storage and loss
moduli are calculated in oscillatory shear, which show that the viscoelastic
properties at low and moderate frequencies are consistent with a Maxwell fluid
behavior. We compare our results with a kinetic theory of dumbbells in
solution, and generally find good agreement.


title: Reconstruction of eye movements during blinks

abstract:
  In eye movement research in reading, the amount of data plays a crucial role
for the validation of results. A methodological problem for the analysis of the
eye movement in reading are blinks, when readers close their eyes. Blinking
rate increases with increasing reading time, resulting in high data losses,
especially for older adults or reading impaired subjects. We present a method,
based on the symbolic sequence dynamics of the eye movements, that reconstructs
the horizontal position of the eyes while the reader blinks. The method makes
use of an observed fact that the movements of the eyes before closing or after
opening contain information about the eyes movements during blinks. Test
results indicate that our reconstruction method is superior to methods that use
simpler interpolation approaches. In addition, analyses of the reconstructed
data show no significant deviation from the usual behavior observed in readers.


title: A Brief Note on Foliations of Constant Gaussian Curvature

abstract:
  This note provides an alternative proof of a result of Labourie. We show that
the two complements of the convex core of a three dimensional quasi-fuchsian
hyperbolic manifold may be foliated by embedded hypersurfaces of constant
Gaussian curvature.


title: Self-dual gravity is completely integrable

abstract:
  We discover multi-Hamiltonian structure of complex Monge-Ampere equation
(CMA) set in a real first-order two-component form. Therefore, by Magri's
theorem this is a completely integrable system in four real dimensions. We
start with Lagrangian and Hamiltonian densities and obtain a symplectic form
and the Hamiltonian operator that determines the Dirac bracket. We have
calculated all point symmetries of two-component CMA system and Hamiltonians of
the symmetry flows. We have found two new real recursion operators for
symmetries which commute with the operator of a symmetry condition on solutions
of the CMA system. These operators form two Lax pairs for the two-component
system. The recursion operators, being applied to the first Hamiltonian
operator, generate infinitely many real Hamiltonian structures. We show how to
construct an infinite hierarchy of higher commuting flows together with the
corresponding infinite chain of their Hamiltonians.


title:
Analytical and numerical aspects on motion of polygonal curves with
  constant area speed

abstract:
  General area-preserving motion of polygonal curves is formulated as a system
of ODEs. Solution polygonal curves belong to a prescribed polygonal class,
which is similar to the admissible class used in the crystalline curvature
flow. The ODEs are discretized implicitly in time keeping a given constant area
speed while solution polygonal curves keep belonging to the polygonal class.


title:
Magnetic and transport properties of electron-doped superconducting thin
  films: Pairing symmetry, pinning and spin fluctuations

abstract:
  In this Chapter we review our latest results on magnetic (AC susceptibility)
and transport (resistivity) properties of Pr1.85Ce0.15CuO4 (PCCO) and
Sm1.85Ce0.15CuO4 (SCCO) thin films grown by pulsed laser deposition technique.
Three main topics of our studies will be covered. We start with a thorough
discussion of the pairing symmetry mechanisms in optimally-doped SCCO thin
films based on the extracted with high accuracy temperature profiles of
penetration depth. In particular, we found that above and below a crossover
temperature T*=0.22T_C, our films are best-fitted by a linear and quadratic
dependencies, respectively, with physically reasonable values of d-wave node
gap parameter and paramagnetic impurity scattering rate. Our next topic is
related to the flux distribution in our films. More precisely, we present a
comparative study on their pinning ability at low magnetic fields extracted
from their AC susceptibilities. Depending on the level of homogeneity of our
films, two different types of the irreversibility line have been found. The
obtained results are described via the critical-state model taking into account
the low-field grain-boundary pinning. And finally, we demonstrate our recent
results on the normal state temperature behavior of resistivity R(T) for the
high-quality optimally-doped SCCO thin films. In addition to the expected
contributions from the electron-phonon and electron-electron scattering
processes, we also observed an unusual step-like behavior of R(T) around T=87K
which we attributed the to the manifestation of thermal excitations due to spin
fluctuations induced by Sm3+ moments through Cu2+-Sm3+ interaction.


title:
Large-Scale Structure of the Molecular Gas in Taurus Revealed by High
  Linear Dynamic Range Spectral Line Mapping

abstract:
  We report the results of a 100 square degree survey of the Taurus Molecular
Cloud region in the J = 1-0 transition of 12CO and 13CO. The image of the cloud
in each velocity channel includes ~ 3 million Nyquist sampled pixels on a 20"
grid. The high sensitivity and large linear dynamic range of the maps in both
isotopologues reveal a very complex, highly structured cloud morphology. There
are large scale correlated structures evident in 13CO emission having very fine
dimensions, including filaments, cavities, and rings. The 12CO emission shows a
quite different structure, with particularly complex interfaces between regions
of greater and smaller column density defining the boundaries of the
largest-scale cloud structures. The axes of the striations seen in the 12CO
emission from relatively diffuse gas are aligned with the direction of the
magnetic field. Using a column density-dependent model for the CO fractional
abundance, we derive the mass of the region mapped to be 24,000 solar masses, a
factor of three greater than would be obtained with canonical CO abundance
restricted to the high column density regions. We determine that half the mass
of the cloud is in regions having column density below 2.1x10^{21} per square
cm. The distribution of young stars in the region covered is highly nonuniform,
with the probability of finding a star in a pixel with a specified column
density rising sharply for N(H2) = 6x10^{21} cm^{-2}. We determine a relatively
low star formation efficiency (mass of young stars/mass of molecular gas),
between 0.3 and 1.2 %, and an average star formation rate during the past 3 Myr
of 8x10^{-5} stars yr^{-1}.


title:
The effect of the dynamical state of clusters on gas expulsion and
  infant mortality

abstract:
  The star formation efficiency (SFE) of a star cluster is thought to be the
critical factor in determining if the cluster can survive for a significant
(>50 Myr) time. There is an often quoted critical SFE of ~30 per cent for a
cluster to survive gas expulsion. I reiterate that the SFE is not the critical
factor, rather it is the dynamical state of the stars (as measured by their
virial ratio) immediately before gas expulsion that is the critical factor. If
the stars in a star cluster are born in an even slightly cold dynamical state
then the survivability of a cluster can be greatly increased.


title:
Laughlin's function on a cylinder: plasma analogy and representation as
  a quantum polymer

abstract:
  We investigate Laughlin's fractional quantum Hall effect wave function in the
cylinder geometry of Laughlin's integer quantum Hall effect argument, at
filling factor 1/3. We show that the plasma analogy leads to a periodic
density, and that the wave function admits a representation as a ``quantum
polymer'', reminiscent of the quantum dimer model by Rokhsar and Kivelson. We
explain how the representation can be exploited to compute the normalization
and one-particle density in the limit of infinitely many particles.


title: Associated Photons and New Physics Signals at Linear Colliders

abstract:
  We study signals for beyond standard model physics and consider the virtues
of single photon signals or associated photons in the final states in
identifying different scenarios of new physics models in a very efficient and
novel way.


title: Thin accretion disc with a corona in a central magnetic field

abstract:
  We study the steady-state structure of an accretion disc with a corona
surrounding a central, rotating, magnetized star. We assume that the
magneto-rotational instability is the dominant mechanism of angular momentum
transport inside the disc and is responsible for producing magnetic tubes above
the disc. In our model, a fraction of the dissipated energy inside the disc is
transported to the corona via these magnetic tubes. This energy exchange from
the disc to the corona which depends on the disc physical properties is
modified because of the magnetic interaction between the stellar magnetic field
and the accretion disc. According to our fully analytical solutions for such a
system, the existence of a corona not only increases the surface density but
reduces the temperature of the accretion disc. Also, the presence of a corona
enhances the ratio of gas pressure to the total pressure. Our solutions show
that when the strength of the magnetic field of the central neutron star is
large or the star is rotating fast enough, profiles of the physical variables
of the disc significantly modify due to the existence of a corona.


title: Boundary effects on the dynamics of chains of coupled oscillators

abstract:
  We study the dynamics of a chain of coupled particles subjected to a
restoring force (Klein-Gordon lattice) in the cases of either periodic or
Dirichlet boundary conditions. Precisely, we prove that, when the initial data
are of small amplitude and have long wavelength, the main part of the solution
is interpolated by a solution of the nonlinear Schr\"odinger equation, which in
turn has the property that its Fourier coefficients decay exponentially. The
first order correction to the solution has Fourier coefficients that decay
exponentially in the periodic case, but only as a power in the Dirichlet case.
In particular our result allows one to explain the numerical computations of
the paper \cite{BMP07}.


title: Lambda(1405) in chiral SU(3) dynamics

abstract:
  We discuss several aspects of the Lambda(1405) resonance in relation to the
recent theoretical developments in chiral dynamics. We derive an effective
single-channel KbarK N interaction based on chiral SU(3) coupled-channel
approach, emphasizing the important role of the pi Sigma channel and the
structure of the Lambda(1405) in Kbar N phenomenology. In order to clarify the
structure of the resonance, we study the behavior with the number of colors
(Nc) of the poles associated with the Lambda(1405), and argue the physical
meaning of the renormalization procedure.


title: Coronal structure of the cTTS V2129 Oph

abstract:
  The nature of the magnetic coupling between T Tauri stars and their disks
determines not only the mass accretion process but possibly the spin evolution
of the central star. We have taken a recently-published surface magnetogram of
one moderately-accreting T Tauri star (V2129 Oph) and used it to extrapolate
the geometry of its large-scale field. We determine the structure of the open
(wind-bearing) field lines, the closed (X-ray bright) field lines and those
potentially accreting field lines that pass through the equatorial plane inside
the Keplerian co-rotation radius. We consider a series of models in which the
stellar magnetic field is opened up by the outward pressure of the hot coronal
gas at a range of radii. As this radius is increased, accretion takes place
along simpler field structures and impacts on fewer sites at the stellar
surface. This is consistent with the observed variation in the Ca II IRT and
HeI lines which suggests that accretion in the visible hemisphere is confined
to a single high-latitude spot. By determining the density and velocity of the
accretion flows, we find that in order to have most of the total mass accretion
rate impacting on a single high-latitude region we need disk material to
accrete from approximately 7R*, close to the Keplerian co-rotation radius at
6.8R*. We also calculate the coronal density and X-ray emission measure. We
find that both the magnitude and rotational modulation of the emission measure
increase as the source surface is increased. For the field structure of V2129
Oph which is dominantly octupolar, the emission forms a bright, high-latitude
ring that is always in view as the star rotates. Since the accretion funnels
are not dense enough to cause significant scattering of coronal X-ray photons,
they provide only a low rotational modulation of around 10% at most.


title: The AUGER experiment - status and results

abstract:
  The Auger experiment was designed to study the high-energy cosmic rays by
measuring the properties of the showers produced in the atmosphere. The
Southern Auger Observatory has taken data since January 2004. Results on mass
composition, energy spectrum and anisotropy of the arrival directions are
presented. The most important result is the recent observation of correlations
with nearby extragalactic objects.


title:
Calculation of the Two-Loop Heavy-Flavor Contribution to Bhabha
  Scattering

abstract:
  We describe in detail the calculation of the two-loop corrections to the QED
Bhabha scattering cross section due to the vacuum polarization by heavy
fermions. Our approach eliminates one mass scale from the most challenging part
of the calculation and allows us to obtain the corrections in a closed
analytical form. The result is valid for arbitrary values of the heavy fermion
mass and the Mandelstam invariants, as long as s,t,u >> m_e^2.


title: Conductivity of the defectless Graphene

abstract:
  Conductivity of the defectless, perfect crystal graphene is found at the
neutrality point at zero temperature and in the limit of large dielectric
constant of the substrate. The steady state of the graphene with weak current
is assumed to be an ideal, rare plasma of particle and hole excitations
governed by the Boltzmann kinetic equation.