title:
A Cosmological Framework for the Co-Evolution of Quasars, Supermassive
  Black Holes, and Elliptical Galaxies: II. Formation of Red Ellipticals

abstract:
  (Abridged) We develop and test a model for the cosmological role of mergers
in the formation and quenching of red, early-type galaxies. Making the ansatz
that star formation is quenched after a gas-rich, spheroid-forming major
merger, we demonstrate that this naturally predicts the turnover in the
efficiency of star formation at ~L_star, as well as the observed mass
functions/density of red galaxies as a function of redshift, the formation
times of spheroids as a function of mass, and the fraction of quenched galaxies
as a function of galaxy and halo mass, environment, and redshift. Comparing to
a variety of semi-analytic models in which quenching is primarily driven by
halo mass considerations or secular/disk instabilities, we demonstrate that our
model and different broad classes of models make unique and robust qualitative
predictions for a number of observables, including the red fraction as a
function of galaxy and halo mass, the density of passive galaxies and evolution
of the color-morphology-density relations at high z, and the fraction of
disky/boxy spheroids as a function of mass. In each case, the observations
favor a model in which galaxies quench after a major merger builds a massive
spheroid, and disfavor quenching via secular or pure halo processes. We discuss
a variety of physical possibilities for this quenching, and propose a mixed
scenario in which traditional quenching in hot, massive halos is supplemented
by the feedback associated with star formation and quasar activity in a major
merger, which temporarily suppress cooling and establish the conditions of a
dynamically hot halo in the central regions of the host, even in low mass
halos.


title: Are all highly liquid securities within the same class?

abstract:
  In this manuscript we analyse the leading statistical properties of
fluctuations of (log) 3-month US Treasury bill quotation in the secondary
market, namely: probability density function, autocorrelation, absolute values
autocorrelation, and absolute values persistency. We verify that this financial
instrument, in spite of its high liquidity, shows very peculiar properties.
Particularly, we verify that log-fluctuations belong to the Levy class of
stochastic variables.


title: Highest Energy Cosmic Rays and results from the HiRes Experiment

abstract:
  The status of the field of ultrahigh energy cosmic rays is summarized, from
the point of view of the latest results of the High Resolution Fly's Eye
(HiRes) Experiment. HiRes results are presented, and compared with those of the
Akeno Giant Air Shower Array (AGASA), plus the Telescope Array and Pierre Auger
experiments. The HiRes measurements of the cosmic ray spectrum, and the
observation of the GZK cutoff are presented. HiRes results on composition,
searches for anisotropy, measurement of the proton-air total cross section, and
shapes of shower profiles are presented.


title: On The Universality Of Central Loops

abstract:
  LC-loops, RC-loops and C-loops are collectively called central loops. It is
shown that an LC(RC)-loop is a left(right) universal loop. But an LC(RC)-loop
is a universal loop if and only if it is a right(left) universal loop. It is
observed that not all RC-loops or LC-loops or C-loops are universal loops. But
if an RC-loop(LC-loop, C-loop) is universal, then it is a right Bol loop(left
Bol loop, Moufang loop) respectively. If a loop and its right or left isotope
are commutative then the loop is a C-loop if and only if its right or left
isotope is a C-loop. If a C-loop is central square and its right or left
isotope is an alternative central square loop, then the latter is a C-loop.
Necessary and sufficient condition for an LC-loop(RC-loop) to be a
left(right)G-loop is established. Consequently, necessary and sufficient
conditions for an LC-loop, and an RC-loop to be a G-loop are established. A
necessary and sufficient condition for a C-loop to be a G-loop is established.


title:
Analytical calculation of the transition to complete phase
  synchronization in coupled oscillators

abstract:
  Here we present a system of coupled phase oscillators with nearest neighbors
coupling, which we study for different boundary conditions. We concentrate at
the transition to total synchronization. We are able to develop exact solutions
for the value of the coupling parameter when the system becomes completely
synchronized, for the case of periodic boundary conditions as well as for an
open chain with fixed ends. We compare the results with those calculated
numerically.


title:
Multiplicities in Pb-Pb central collisions at the LHC from running
  coupling evolution and RHIC data

abstract:
  Predictions for the pseudorapidity density of charged particles produced in
Pb-Pb central collisions at $\sqrt{s_{NN}}=5.5$ TeV are presented. Particle
production in such collisions is computed in the framework of
k_t-factorization, using running coupling non-linear evolution to determine the
transverse momentum and rapidity dependence of the nuclear unintegrated gluon
distributions.


title:
Theory of the Observed Ultra-Low Friction between Sliding
  Polyelectrolyte Brushes

abstract:
  It is shown using a method based on a modified version of the mean field
theory of Miklavic Marcelja that it should be possible for osmotic pressure due
to the counterions associated with the two polyelectrolyte polymer brush coated
surfaces to support a reasonable load (i.e., about $10^6 Pa$) with the brushes
held sufficiently far apart to prevent entanglement of polymers belonging to
the two brushes, thus avoiding what is believed to be the dominant mechanisms
for static and dry friction.


title:
Finite temperature phase diagram of trapped Fermi gases with population
  imbalance

abstract:
  We consider a trapped Fermi gas with population imbalance at finite
temperatures and map out the detailed phase diagram across a wide Feshbach
resonance. We take the Larkin-Ovchinnikov-Fulde-Ferrel (LOFF) state into
consideration and minimize the thermodynamical potential to ensure stability.
Under the local density approximation, we conclude that a stable LOFF state is
present only on the BCS side of the Feshbach resonance, but not on the BEC side
or at unitarity. Furthermore, even on the BCS side, a LOFF state is restricted
at low temperatures and in a small region of the trap, which makes a direct
observation of LOFF state a challenging task.


title: Fractional Laplacian in Bounded Domains

abstract:
  The fractional Laplacian operator, $-(-\triangle)^{\frac{\alpha}{2}}$,
appears in a wide class of physical systems, including L\'evy flights and
stochastic interfaces. In this paper, we provide a discretized version of this
operator which is well suited to deal with boundary conditions on a finite
interval. The implementation of boundary conditions is justified by appealing
to two physical models, namely hopping particles and elastic springs. The
eigenvalues and eigenfunctions in a bounded domain are then obtained
numerically for different boundary conditions. Some analytical results
concerning the structure of the eigenvalues spectrum are also obtained.


title:
Measuring the spin polarization and Zeeman energy of a spin-polarized
  electron gas: Comparison between Raman scattering and photoluminescence

abstract:
  We compare resonant electronic Raman scattering and photoluminescence
measurements for the characterization of a spin-polarized two-dimensional
electron gas embedded in $\text{Cd}_{1-x}\text{Mn}_x\text{Te}$ single quantum
wells. From Raman scattering by single-particle excitations in a zero magnetic
field, we measure the Fermi velocity and then obtain the Fermi energy (as well
as the electron density), which is comparable to that extracted from
photoluminescence for moderate electron densities, assuming a bare band-edge
mass. At large electron densities, the Fermi energies derived from Raman
scattering and photoluminescence differ. For an applied in-plane magnetic field
and zero wave vector transferred to the electron gas, Raman scattering spectra
show peaks at both the Zeeman energy $Z$, resulting from collective excitations
of the spin-polarized electron gas, and the one electron spin-flip energy
$Z^*$. Magneto-photoluminescence spectra show conduction band splitting that
are equivalent to $Z$, suggesting that collective effects are present in the
photoluminescence spectra. Assuming (as before) an uncorrected mass, the degree
of spin polarization $\zeta$ determined from the magneto-photoluminescence
lineshape is found to differ from that derived from the magnetic field
dependent Raman scattering measurements for large electron densities. We
attribute the discrepancy in measuring $\zeta$ and the Fermi energy to the
renormalized mass resulting from many-body electron-electron interactions.


title:
Search for Gamma Ray Bursts using the single particle technique at the
  Pierre Auger Observatory

abstract:
  The Pierre Auger Observatory, with an array of currently more than 1200
Cherenkov detectors filled with 12 m$^3$ of water, can detect the putative high
energy emission of a GRB (photons down to a few hundreds of MeV) by the
so-called ``single particle technique'', through a coherent increase in the
average background particle rates over the whole array, due to secondary
particles in the photon-induced showers. We present a search for bursts on data
collected since September 2005, as well as a search for excesses in coincidence
with bursts observed by satellites.


title:
Detection of GRB 060927 at z = 5.47: Implications for the Use of
  Gamma-Ray Bursts as Probes of the End of the Dark Ages

abstract:
  We report on follow-up observations of the GRB 060927 using the ROTSE-IIIa
telescope and a suite of larger aperture ground-based telescopes. An optical
afterglow was detected 20 s after the burst, the earliest rest-frame detection
of optical emission from any GRB. Spectroscopy performed with the VLT about 13
hours after the trigger shows a continuum break at lambda ~ 8070 A produced by
neutral hydrogen absorption at z~5.6. We also detect an absorption line at 8158
A which we interpret as SiII at z=5.467. Hence, GRB 060927 is the second most
distant GRB with a spectroscopically measured redshift. The shape of the red
wing of the spectral break can be fitted by a damped Lyalpha profile with a
column density with log(N_HI/cm^-2) ~ 22.5. We discuss the implications of this
work for the use of GRBs as probes of the end of the dark ages and draw three
main conclusions: i) GRB afterglows originating from z>6 should be relatively
easy to detect from the ground, but rapid NIR monitoring is necessary to ensure
that they are found; ii) The presence of large HI column densities in some GRBs
host galaxies at z>5 makes the use of GRBs to probe the reionization epoch via
spectroscopy of the red damping wing challenging; iii) GRBs appear crucial to
locate typical star-forming galaxies at z>5 and therefore the type of galaxies
responsible for the reionization of the universe.


title: Hestenes' Tetrad and Spin Connections

abstract:
  Defining a spin connection is necessary for formulating Dirac's bispinor
equation in a curved space-time. Hestenes has shown that a bispinor field is
equivalent to an orthonormal tetrad of vector fields together with a complex
scalar field. In this paper, we show that using Hestenes' tetrad for the spin
connection in a Riemannian space-time leads to a Yang-Mills formulation of the
Dirac Lagrangian in which the bispinor field is mapped to a set of Yang-Mills
gauge potentials and a complex scalar field. This result was previously proved
for a Minkowski space-time using Fierz identities. As an application we derive
several different non-Riemannian spin connections found in the literature
directly from an arbitrary linear connection acting on Hestenes' tetrad and
scalar fields. We also derive spin connections for which Dirac's bispinor
equation is form invariant. Previous work has not considered form invariance of
the Dirac equation as a criterion for defining a general spin connection.


title: Quantum Fields on the Groenewold-Moyal Plane: C, P, T and CPT

abstract:
  We show that despite the inherent non-locality of quantum field theories on
the Groenewold-Moyal (GM) plane, one can find a class of ${\bf C}$, ${\bf P}$,
${\bf T}$ and ${\bf CPT}$ invariant theories. In particular, these are theories
without gauge fields or with just gauge fields and no matter fields. We also
show that in the presence of gauge fields, one can have a field theory where
the Hamiltonian is ${\bf C}$ and ${\bf T}$ invariant while the $S$-matrix
violates ${\bf P}$ and ${\bf CPT}$.
  In non-abelian gauge theories with matter fields such as the electro-weak and
$QCD$ sectors of the standard model of particle physics, ${\bf C}$, ${\bf P}$,
${\bf T}$ and the product of any pair of them are broken while ${\bf CPT}$
remains intact for the case $\theta^{0i} =0$. (Here $x^{\mu} \star x^{\nu} -
x^{\nu} \star x^{\mu} = i \theta^{\mu \nu}$, $x^{\mu}$: coordinate functions,
$\theta^{\mu \nu} = -\theta^{\nu \mu}=$ constant.) When $\theta^{0i} \neq 0$,
it contributes to breaking also ${\bf P}$ and ${\bf CPT}$. It is known that the
$S$-matrix in a non-abelian theory depends on $\theta^{\mu \nu}$ only through
$\theta^{0i}$. The $S$-matrix is frame dependent. It breaks (the identity
component of the) Lorentz group. All the noncommutative effects vanish if the
scattering takes place in the center-of-mass frame, or any frame where
$\theta^{0i}P^{\textrm{in}}_{i} = 0$, but not otherwise. ${\bf P}$ and ${\bf
CPT}$ are good symmetries of the theory in this special case.


title: Optical coupling to spin waves in the cycloidal multiferroic BiFeO3

abstract:
  The magnon and optical phonon spectrum of an incommensurate multiferroic such
as BiFeO3 is considered in the framework of a phenomenological Landau theory.
The resulting spin wave spectrum is quite distinct from commensurate substances
due to soft mode anisotropy and magnon zone folding. The former allows
electrical control of spin wave propagation via reorientation of the
spontaneous ferroelectric moment. The latter gives rise to multiple
magneto-dielectric resonances due to the coupling of optical phonons at zero
wavevector to magnons at integer multiples of the cycloid wavevector. These
results show that the optical response of a multiferroic reveals much more
about its magnetic excitations than previously anticipated on the basis of
simpler models.


title: Partitioning of a polymer chain between a confining cavity and a gel

abstract:
  A lattice field theory approach to the statistical mechanics of charged
polymers in electrolyte solutions [S. Tsonchev, R. D. Coalson, and A. Duncan,
Phys. Rev. E 60, 4257, (1999)] is applied to the study of a polymer chain
contained in a spherical cavity but able to diffuse into a surrounding gel. The
distribution of the polymer chain between the cavity and the gel is described
by its partition coefficient, which is computed as a function of the number of
monomers in the chain, the monomer charge, and the ion concentrations in the
solution.


title: Pattern of Light Scalar Mesons

abstract:
  Combining the recent lattice calculation of $a_0(1450)$ and $\sigma(600)$
mesons with the overlap fermion in the chiral regime with the pion mass less
than $300 {\rm MeV}$, the quenched lattice calculation of the scalar glueball,
and the phenomenological study of the mixing of isoscalar scalar mesons
$f_0(1710)$, $f_0(1500)$, $f_0(1370)$ through their decays, a simple pattern
for the light scalar mesons begins to emerge. Below 1 GeV, the scalar mesons
form a nonet of tetraquark mesoniums. Above 1 GeV, the nonent $q\bar{q}$ mesons
are made of an octet with largely unbroken SU(3) symmetry and a fairly good
singlet which is $f_0(1370)$. $f_0(1710)$ is identified as an almost pure
scalar glueball with a $\sim 10%$ mixture of $q\bar{q}$.


title: Remark on the rank of elliptic curves

abstract:
  A covariant functor on the elliptic curves with complex multiplication is
constructed. The functor takes values in the noncommutative tori with real
multiplication. A conjecture on the rank of an elliptic curve is formulated.


title: Interactions of Cosmic Superstrings

abstract:
  We develop methods by which cosmic superstring interactions can be studied in
detail. These include the reconnection probability and emission of radiation
such as gravitons or small string loops. Loop corrections to these are
discussed, as well as relationships to $(p,q)$-strings. These tools should
allow a phenomenological study of string models in anticipation of upcoming
experiments sensitive to cosmic string radiation.


title: EF Cha: Warm Dust Orbiting a Nearby 10 Myr Old Star

abstract:
  Most Vega-like stars have far-infrared excess (60micron or longward in IRAS,
ISO, or Spitzer MIPS bands) and contain cold dust (<~150K) analogous to the
Sun's Kuiper-Belt region. However, dust in a region more akin to our asteroid
belt and thus relevant to the terrestrial planet building process is warm and
produces excess emission in mid-infrared wavelengths. By cross-correlating
Hipparcos dwarfs with the MSX catalog, we found that EF Cha, a member of the
recently identified, ~10 Myr old, ``Cha-Near'' Moving Group, possesses
prominent mid-infrared excess. N-band spectroscopy reveals a strong emission
feature characterized by a mixture of small, warm, amorphous and possibly
crystalline silicate grains. Survival time of warm dust grains around this A9
star is <~ 1E5 yrs, much less than the age of the star. Thus, grains in this
extra-solar terrestrial planetary zone must be of "second generation" and not a
remnant of primodial dust and are suggestive of substantial planet formation
activity. Such second generation warm excess occurs around ~ 13% of the
early-type stars in nearby young stellar associations.


title:
Lieb-Wu Solution, Gutzwiller-Wave-Function, and Gutzwiller-Ansatz
  Approximation, with Adjustable Single-Particle Wave Function for the Hubbard
  Chain

abstract:
  The optimized single-particle wave functions contained in the parameters of
the Hubbard model (t and U) were determined for an infinite atomic chain. In
effect, the electronic properties of the chain as a function of interatomic
distance R were obtained and compared for the Lieb - Wu exact solution (LW),
the Gutzwiller-Wave-Function approximation (GWF), and the Gutzwiller-ansatz
case (GA). The ground state energy and other characteristics for the infinite
chain were also compared with those obtained earlier for a nanoscopic chain
within the Exact Diagonalization combined with an Ab Initio adjustment of the
single-particle wave functions in the correlated state (EDABI method). For the
sake of completeness, we briefly characterize also each of the solutions. Our
approach completes the Lieb-Wu solution, as it provides the system electronic
properties evolution as a function of physically controllable parameter - the
interatomic distance.


title:
Several experimental realizations of symmetric phase-covariant quantum
  cloner of single-photon qubits

abstract:
  We compare several optical implementations of phase-covariant cloning
machines. The experiments are based on copying of the polarization state of a
single photon in bulk optics by special unbalanced beam splitter or by balanced
beam splitter accompanied by a state filtering. Also the all-fiber based setup
is discussed, where the information is encoded into spatial modes, i.e., the
photon can propagate through two optical fibers. Each of the four
implementations possesses some advantages and disadvantages that are discussed.


title: Tunneling between Dilute GaAs Hole Layers

abstract:
  We report interlayer tunneling measurements between very dilute
two-dimensional GaAs hole layers. Surprisingly, the shape and
temperature-dependence of the tunneling spectrum can be explained with a Fermi
liquid-based tunneling model, but the peak amplitude is much larger than
expected from the available hole band parameters. Data as a function of
parallel magnetic field reveal additional anomalous features, including a
recurrence of a zero-bias tunneling peak at very large fields. In a
perpendicular magnetic field, we observe a robust and narrow tunneling peak at
total filling factor $\nu_T=1$, signaling the formation of a bilayer quantum
Hall ferromagnet.


title: Metastable Vacua in Brane Worlds

abstract:
  We analyze vacuum decay in brane world setups, where a free scalar field in
five dimensions has a localized potential admitting metastable vacua. We study
in particular the bounce solution and its properties in flat and warped spaces.
In the latter case, placing into a deeply warped region the term in the
potential that lifts the vacuum degeneracy, can increase indefinitely the
lifetime of the false vacuum. We discuss the application to metastable vacua in
supersymmetric brane-world constructions.


title: The Cosmic Code Comparison Project

abstract:
  Current and upcoming cosmological observations allow us to probe structures
on smaller and smaller scales, entering highly nonlinear regimes. In order to
obtain theoretical predictions in these regimes, large cosmological simulations
have to be carried out. The promised high accuracy from observations make the
simulation task very demanding: the simulations have to be at least as accurate
as the observations. This requirement can only be fulfilled by carrying out an
extensive code validation program. The first step of such a program is the
comparison of different cosmology codes including gravitation interactions
only. In this paper we extend a recently carried out code comparison project to
include five more simulation codes. We restrict our analysis to a small
cosmological volume which allows us to investigate properties of halos. For the
matter power spectrum and the mass function, the previous results hold, with
the codes agreeing at the 10% level over wide dynamic ranges. We extend our
analysis to the comparison of halo profiles and investigate the halo count as a
function of local density. We introduce and discuss ParaView as a flexible
analysis tool for cosmological simulations, the use of which immensely
simplifies the code comparison task.


title: Agujeros de Gusano en Gravedad (2+1)

abstract:
  Traversable wormholes are objects that present a lot of interest in the last
years because of their geometric features and their relation with exotic
matter. In this paper we presnt a review of the principal characteristics of
traversable Morris-Thorne wormholes, their construction proccess and some
aspects about the exotic matter that is needed in order to mantain them. Then,
we use a junction proccess to obatin two specific wormhole solutions in the
(2+1) gravity formalism with negative cosmological constant. The obtained
solutions represent wormholes with an external spacetime correspondient to the
BTZ black hole solution. We also show that exotic matter is needed to mantain
these wormholes.
  -----
  Los agujeros de gusano atravesables son objetos que presentan un gran interes
en la actualidad debido a sus caracteristicas geometricas y a su relacion con
la materia exotica. En el presente trabajo se muestra una revision de las
caracteristicas de los agujeros de gusano atravesables al estilo de Morris y
Thorne, al igual que el proceso de construccion y aspectos de la materia
exotica necesaria para mantenerlos. Luego, se utiliza un proceso de juntura
para construir dos soluciones especificas tipo agujero de gusano en el
formalismo de la gravedad (2+1) con constante cosmologica negativa. Con esta
construccion, se obtienen agujeros atravesables que se encuentran unidos a un
espacio-tiempo externo correspondiente al agujero negro BTZ sin momento angular
y sin carga electrica. Ademas de esto, se muestra que para mantener este tipo
de solucion es necesaria la existencia de materia exotica, es decir, materia
que viole las condiciones de energia.


title:
Grain Retention and Formation of Planetesimals near the Snow Line in
  MRI-driven Turbulent Protoplanetary Disks

abstract:
  The first challenge in the formation of both terrestrial planets and the
cores of gas giants is the retention of grains in protoplanetary disks. In most
regions of these disks, gas attains sub-Keplerian speeds as a consequence of a
negative pressure gradient. Hydrodynamic drag leads to orbital decay and
depletion of the solid material in the disk, with characteristic timescales as
short as only a few hundred years for meter-sized objects at 1 AU. In this
paper, we suggest a particle retention mechanism which promotes the
accumulation of grains and the formation of planetesimals near the water
sublimation front or ``snow line.'' This model is based on the assumption that,
in the regions most interesting for planet formation, the viscous evolution of
the disk is due to turbulence driven by the magneto-rotational instability
(MRI) in the surface layers of the disk. The depth to which MRI effectively
generates turbulence is a strong function of the grain size and abundance. A
sharp increase in the grain-to-gas density ratio across the snow line reduces
the column depth of the active layer. As the disk evolves towards a
quasi-steady-state, this change in the active layer creates a local maximum in
radial distribution of the gas surface density and pressure, causing the gas to
rotate at super-Keplerian speed and halting the inward migration of grains.
This senario presents a robust process for grain retention which may aid in the
formation of proto-gas-giant cores preferentially near the snow line.


title: Multicolor observations of the afterglow of the short/hard GRB 050724

abstract:
  New information on short/hard gamma-ray bursts (GRBs) is being gathered
thanks to the discovery of their optical and X-ray afterglows. However, some
key aspects are still poorly understood, including the collimation level of the
outflow, the duration of the central engine activity, and the properties of the
progenitor systems. We want to constrain the physical properties of the short
GRB 050724 and of its host galaxy, and make some inferences on the global short
GRB population. We present optical observations of the afterglow of GRB 050724
and of its host galaxy, significantly expanding the existing dataset for this
event. We compare our results with models, complementing them with available
measurements from the literature. We study the afterglow light curve and
spectrum including X-ray data. We also present observations of the host galaxy.
The observed optical emission was likely related to the large flare observed in
the X-ray light curve. The apparent steep decay was therefore not due to the
jet effect. Available data are indeed consistent with low collimation, in turn
implying a large energy release, comparable to that of long GRBs. The flare
properties also constrain the internal shock mechanism, requiring a large
Lorentz factor contrast between the colliding shells. This implies that the
central engine was active at late times, rather than ejecting all shells
simultaneously. The host galaxy has red colors and no ongoing star formation,
consistent with previous findings on this GRB. However, it is not a pure
elliptical, and has some faint spiral structure. GRB 050724 provides the most
compelling case for association between a short burst and a galaxy with old
stellar population. It thus plays a pivotal role in constraining progenitors
models, which should allow for long delays between birth and explosion.


title: Feedback Heating by Cosmic Rays in Clusters of Galaxies

abstract:
  Recent observations show that the cooling flows in the central regions of
galaxy clusters are highly suppressed. Observed AGN-induced cavities/bubbles
are a leading candidate for suppressing cooling, usually via some form of
mechanical heating. At the same time, observed X-ray cavities and synchrotron
emission point toward a significant non-thermal particle population. Previous
studies have focused on the dynamical effects of cosmic-ray pressure support,
but none have built successful models in which cosmic-ray heating is
significant. Here we investigate a new model of AGN heating, in which the
intracluster medium is efficiently heated by cosmic-rays, which are injected
into the ICM through diffusion or the shredding of the bubbles by
Rayleigh-Taylor or Kelvin-Helmholtz instabilities. We include thermal
conduction as well. Using numerical simulations, we show that the cooling
catastrophe is efficiently suppressed. The cluster quickly relaxes to a
quasi-equilibrium state with a highly reduced accretion rate and temperature
and density profiles which match observations. Unlike the conduction-only case,
no fine-tuning of the Spitzer conduction suppression factor f is needed. The
cosmic ray pressure, P_c/P_g <~ 0.1 and dP_c/dr <~ 0.1 \rho g, is well within
observational bounds. Cosmic ray heating is a very attractive alternative to
mechanical heating, and may become particularly compelling if GLAST detects the
gamma-ray signature of cosmic-rays in clusters.


title:
A Complete Catalog of Swift GRB Spectra and Durations: Demise of a
  Physical Origin for Pre-Swift High-Energy Correlations

abstract:
  We calculate durations and spectral paramaters for 218 Swift bursts detected
by the BAT instrument between and including GRBs 041220 and 070509, including
77 events with measured redshifts. Incorporating prior knowledge into the
spectral fits, we are able to measure the characteristic $\nu F_{\nu}$ spectral
peak energy $E_{\rm pk,obs}$ and the isotropic equivalent energy $E_{\rm iso}$
(1--$10^4$ keV) for all events. This complete and rather extensive catalog,
analyzed with a unified methodology, allows us to address the persistence and
origin of high-energy correlations suggested in pre-Swift observations. We find
that the $E_{\rm pk,obs}$-$E_{\rm iso}$ correlation is present in the Swift
sample; however, the best-fit powerlaw relation is inconsistent with the
best-fit pre-Swift relation at >5 sigma significance. Moreover, it has a factor
>~ 2 larger intrinsic scatter, after accounting for large errors on $E_{\rm
pk,obs}$. A large fraction of the Swift events are hard and subluminous
relative to (and inconsistent with) the pre-Swift relation, in agreement with
indications from BATSE GRBs without redshift. Moreover, we determine an
experimental threshold for the BAT detector and show how the $E_{\rm
pk,obs}$--$E_{\rm iso}$ correlation arises artificially due to partial
correlation with the threshold. We show that pre-Swift correlations found by
Amati et al.(2002), Yonetoku et al. (2004), Firmani et al.(2006) (and
independently by others) are likely unrelated to the physical properties of
GRBs and are likely useless for tests of cosmology. Also, an explanation of
these correlations in terms of a detector threshold provides a natural and
quantitative explanation for why short-duration GRBs and events at low redshift
tend to be outliers to the correlations.


title:
Loop coproducts in string topology and triviality of higher genus TQFT
  operations

abstract:
  Cohen and Godin constructed positive boundary topological quantum field
theory (TQFT) structure on the homology of free loop spaces of oriented closed
smooth manifolds by associating a certain operations called string operations
to orientable surfaces with parametrized boundaries. We show that all TQFT
string operations associated to surfaces of genus at least one vanish
identically. This is a simple consequence of properties of the loop coproduct
which will be discussed in detail. One interesting property is that the loop
coproduct is nontrivial only on the degree $d$ homology group of the connected
component of $LM$ consisting of contractible loops, where $d=\dim M$, with
values in the degree 0 homology group of constant loops. Thus the loop
coproduct behaves in a dramatically simpler way than the loop product.


title: A Homotopy Theoretic Proof of the BV Identity in Loop Homology

abstract:
  Chas and Sullivan proved the existence of a Batalin-Vilkovisky algebra
structure in the homology of free loop spaces on closed finite dimensional
smooth manifolds using chains and chain homotopies. This algebraic structure
involves an associative product called the loop product, a Lie bracket called
the loop bracket, and a square 0 operator called the BV operator. Cohen and
Jones gave a homotopy theoretic description of the loop product in terms of
spectra. In this paper, we give an explicit homotopy theoretic description of
the loop bracket and, using this description, we give a homological proof of
the BV identity connecting the loop product, the loop bracket, and the BV
operator. The proof is based on an observation that the loop bracket and the BV
derivation are given by the same cycle in the free loop space, except that they
differ by parametrization of loops.


title: Higgs Searches at the Tevatron

abstract:
  Recent preliminary results obtained by the CDF and D0 Collaborations on
searches for the Higgs boson in proton anti-proton collisions at Sqrt(s)=1.96
TeV at the Fermilab Tevatron collider are discussed. The data, corresponding to
integrated luminosities of about 1 fb-1, show no excess of a signal above the
expected background in any of the decay channels examined. Instead, upper
limits at 95% Confidence Level on the cross section are established. Further, a
combined Standard Model Tevatron cross section limit is presented.


title:
The wedding of modified dynamics and non-exotic dark matter in galaxy
  clusters

abstract:
  We summarize the status of Modified Newtonian Dynamics (MOND) in galaxy
clusters. The observed acceleration is typically larger than the acceleration
threshold of MOND in the central regions, implying that some dark matter is
necessary to explain the mass discrepancy there. A plausible resolution of this
issue is that the unseen mass in MOND is in the form of ordinary neutrinos with
masses just below the experimentally detectable limit. In particular, we show
that the lensing mass reconstructions of the clusters 1E0657-56 (the bullet
cluster) and Cl0024+17 (the ring) do not pose a new challenge to this scenario.
However, the mass discrepancy for cool X-ray emitting groups, in which
neutrinos cannot cluster, pose a more serious problem, meaning that dark
baryons could present a more satisfactory solution to the problem of unseen
mass in MOND clusters.


title:
The Extensive Special Relativity and Comment on Local Lorentz
  Transformation in Varying Speed of Light Theory

abstract:
  It is proved that local Lorentz transformations for different systems cannot
derive varying speed of light. Based on the special relativity principle, an
invariant speed is necessarily obtained. Therefore, the exact basic principles
of the special relativity should be redefined as: I. The special relativity
principle, which derives necessarily an invariant speed. II. Suppose that the
invariant speed in the theory is the speed of light in the vacuum c. If the
second principle does not hold, for example, the superluminal motions exist,
the theory will be still the extensive special relativity, in which the
formulations are the same, only c is replaced by the invariant speed. If the
invariant speed are various invariant velocities, the diversity of space-time
will correspond to many worlds. Varying speed of light theory is probably
connected only with the general relativity.


title:
Gauge-Higgs Unification and Radiative Electroweak Symmetry Breaking in
  Warped Extra Dimensions

abstract:
  We compute the Coleman Weinberg effective potential for the Higgs field in RS
Gauge-Higgs unification scenarios based on a bulk SO(5) x U(1)_X gauge
symmetry, with gauge and fermion fields propagating in the bulk and a custodial
symmetry protecting the generation of large corrections to the T parameter and
the coupling of the Z to the bottom quark. We demonstrate that electroweak
symmetry breaking may be realized, with proper generation of the top and bottom
quark masses for the same region of bulk mass parameters that lead to good
agreement with precision electroweak data in the presence of a light Higgs. We
compute the Higgs mass and demonstrate that for the range of parameters for
which the Higgs boson has Standard Model-like properties, the Higgs mass is
naturally in a range that varies between values close to the LEP experimental
limit and about 160 GeV. This mass range may be probed at the Tevatron and at
the LHC. We analyze the KK spectrum and briefly discuss the phenomenology of
the light resonances arising in our model.


title:
Folding model study of the isobaric analog excitation: isovector density
  dependence, Lane potential and nuclear symmetry energy

abstract:
  A consistent folding model analysis of the ($\Delta S=0, \Delta T=1$) charge
exchange \pn reaction measured with $^{48}$Ca, $^{90}$Zr, $^{120}$Sn and
$^{208}$Pb targets at the proton energies of 35 and 45 MeV is done within a
two-channel coupling formalism. The nuclear ground state densities given by the
Hartree-Fock-Bogoljubov formalism and the density dependent CDM3Y6 interaction
were used as inputs for the folding calculation of the nucleon optical
potential and \pn form factor. To have an accurate isospin dependence of the
interaction, a complex isovector density dependence of the CDM3Y6 interaction
has been carefully calibrated against the microscopic Brueckner-Hatree-Fock
calculation by Jeukenne, Lejeune and Mahaux before being used as folding input.
Since the isovector coupling was used to explicitly link the isovector part of
the nucleon optical potential to the cross section of \pn reaction exciting the
0$^+$ isobaric analog states in $^{48}$Sc, $^{90}$Nb, $^{120}$Sb and
$^{208}$Bi, the newly parameterized isovector density dependence could be well
tested in the folding model analysis of the \pn reaction. The isospin- and
density dependent CDM3Y6 interaction was further used in the Hartree-Fock
calculation of asymmetric nuclear matter, and a realistic estimation of the
nuclear symmetry energy has been made.


title:
Host Galaxies Catalog Used in LIGO Searches for Compact Binary
  Coalescence Events

abstract:
  An up-to-date catalog of nearby galaxies considered as hosts of binary
compact objects is provided with complete information about sky position,
distance, extinction-corrected blue luminosity and error estimates. With our
current understanding of binary evolution, rates of formation and coalescence
for binary compact objects scale with massive-star formation and hence the
(extinction-corrected) blue luminosity of host galaxies. Coalescence events in
binary compact objects are among the most promising gravitational-wave sources
for ground-based gravitational-wave detectors such as LIGO. Our catalog and
associated error estimates are important for the interpretation of analyses,
carried out for LIGO, to constrain the rates of compact binary coalescence,
given an astrophysical population model for the sources considered. We discuss
how the notion of effective distance, created to account for the antenna
pattern of a gravitational-wave detector, must be used in conjunction with our
catalog. We note that the catalog provided can be used on other astronomical
analysis of populations that scale with galaxy blue luminosity.


title: Long-range Electron Spin-spin Interactions from Unparticle Exchange

abstract:
  Unparticles as suggested by Georgi are identities that are not constrained by
dispersion relations but are governed by their scaling dimension, d. Their
coupling to particles can result in macroscopic interactions between matter,
that are generally an inverse nonintegral power of distance. This is totally
different from known macroscopic forces. We use the precisely measured
long-ranged spin-spin interaction of electrons to constrain unparticle
couplings to the electron. For 1<d<1.5 the axial vector unparticle coupling is
excluded; and for 1<d<1.3 the pseudoscalar and vector couplings are also ruled
out. These bounds and the ones for other ranges of d exceed or are
complementary to those obtained previously from exotic positronium decays.


title: Characterizing the Low-Redshift Intergalactic Medium towards PKS1302-102

abstract:
  We present a detailed analysis of the intergalactic metal-line absorption
systems in the archival HST/STIS and FUSE ultraviolet spectra of the
low-redshift quasar PKS1302-102 (z_QSO = 0.2784). We supplement the archive
data with CLOUDY ionization models and a survey of galaxies in the quasar
field. There are 15 strong Lya absorbers with column densities logN_HI > 14. Of
these, six are associated with at least CIII 977 absorption (logN(C^++) > 13);
this implies a redshift density dN_CIII/dz = 36+13/-9 (68% confidence limits)
for the five detections with rest equivalent width W_r > 50 mA. Two systems
show OVI 1031,1037 absorption in addition to CIII (logN(O^+5) > 14). One is a
partial Lyman limit system (logN_HI = 17) with associated CIII, OVI, and SiIII
1206 absorption. There are three tentative OVI systems that do not have CIII
detected. For one OVI doublet with both lines detected at 3 sigma with W_r > 50
mA, dN_OVI/dz = 7+9/-4. We also search for OVI doublets without Lya absorption
but identify none. From CLOUDY modeling, these metal-line systems have
metallicities spanning the range -4 < [M/H] < -0.3. The two OVI systems with
associated CIII absorption cannot be single-phase, collisionally-ionized media
based on the relative abundances of the metals and kinematic arguments. From
the galaxy survey, we discover that the absorption systems are in a diverse set
of galactic environments. Each metal-line system has at least one galaxy within
500 km/s and 600 h^-1 kpc with L > 0.1 L_*.


title: Framed bicategories and monoidal fibrations

abstract:
  In some bicategories, the 1-cells are `morphisms' between the 0-cells, such
as functors between categories, but in others they are `objects' over the
0-cells, such as bimodules, spans, distributors, or parametrized spectra. Many
bicategorical notions do not work well in these cases, because the `morphisms
between 0-cells', such as ring homomorphisms, are missing. We can include them
by using a pseudo double category, but usually these morphisms also induce base
change functors acting on the 1-cells. We avoid complicated coherence problems
by describing base change `nonalgebraically', using categorical fibrations. The
resulting `framed bicategories' assemble into 2-categories, with attendant
notions of equivalence, adjunction, and so on which are more appropriate for
our examples than are the usual bicategorical ones.
  We then describe two ways to construct framed bicategories. One is an
analogue of rings and bimodules which starts from one framed bicategory and
builds another. The other starts from a `monoidal fibration', meaning a
parametrized family of monoidal categories, and produces an analogue of the
framed bicategory of spans. Combining the two, we obtain a construction which
includes both enriched and internal categories as special cases.


title:
Bayesian Covariance Matrix Estimation using a Mixture of Decomposable
  Graphical Models

abstract:
  A Bayesian approach is used to estimate the covariance matrix of Gaussian
data. Ideas from Gaussian graphical models and model selection are used to
construct a prior for the covariance matrix that is a mixture over all
decomposable graphs. For this prior the probability of each graph size is
specified by the user and graphs of equal size are assigned equal probability.
Most previous approaches assume that all graphs are equally probable. We show
empirically that the prior that assigns equal probability over graph sizes
outperforms the prior that assigns equal probability over all graphs, both in
identifying the correct decomposable graph and in more efficiently estimating
the covariance matrix.


title: Polarization sensitive spectroscopy of charged Quantum Dots

abstract:
  We present an experimental and theoretical study of the polarized
photoluminescence spectrum of single semiconductor quantum dots in various
charge states. We compare our high resolution polarization sensitive spectral
measurements with a new many-carrier theoretical model, which was developed for
this purpose. The model considers both the isotropic and anisotropic exchange
interactions between all participating electron-hole pairs. With this addition,
we calculate both the energies and polarizations of all optical transitions
between collective, quantum dot confined charge carrier states. We succeed in
identifying most of the measured spectral lines. In particular, the lines
resulting from singly-, doubly- and triply- negatively charged excitons and
biexcitons. We demonstrate that lines emanating from evenly charged states are
linearly polarized. Their polarization direction does not necessarily coincide
with the traditional crystallographic direction. It depends on the shells of
the single carriers, which participate in the recombination process.


title:
The Hitchin Model, Poisson-quasi-Nijenhuis Geometry and Symmetry
  Reduction

abstract:
  We revisit our earlier work on the AKSZ formulation of topological sigma
model on generalized complex manifolds, or Hitchin model. We show that the
target space geometry geometry implied by the BV master equations is
Poisson--quasi--Nijenhuis geometry recently introduced and studied by Sti\'enon
and Xu (in the untwisted case). Poisson--quasi--Nijenhuis geometry is more
general than generalized complex geometry and comprises it as a particular
case. Next, we show how gauging and reduction can be implemented in the Hitchin
model. We find that the geometry resulting form the BV master equation is
closely related to but more general than that recently described by Lin and
Tolman, suggesting a natural framework for the study of reduction of
Poisson--quasi--Nijenhuis manifolds.


title: Temporal Reasoning without Transitive Tables

abstract:
  Representing and reasoning about qualitative temporal information is an
essential part of many artificial intelligence tasks. Lots of models have been
proposed in the litterature for representing such temporal information. All
derive from a point-based or an interval-based framework. One fundamental
reasoning task that arises in applications of these frameworks is given by the
following scheme: given possibly indefinite and incomplete knowledge of the
binary relationships between some temporal objects, find the consistent
scenarii between all these objects. All these models require transitive tables
-- or similarly inference rules-- for solving such tasks. We have defined an
alternative model, S-languages - to represent qualitative temporal information,
based on the only two relations of \emph{precedence} and \emph{simultaneity}.
In this paper, we show how this model enables to avoid transitive tables or
inference rules to handle this kind of problem.


title: Self-adjointness of Dirac operators via Hardy-Dirac inequalities

abstract:
  Distinguished selfadjoint extensions of Dirac operators are constructed for a
class of potentials including Coulombic ones up to the critical case,
$-|x|^{-1}$. The method uses Hardy-Dirac inequalities and quadratic form
techniques.


title: A Catalog of HI Clouds in the Large Magellanic Cloud

abstract:
  A 21 cm neutral hydrogen interferometric survey of the Large Magellanic Cloud
(LMC) combined with the Parkes multi-beam HI single-dish survey clearly shows
that the HI gas is distributed in the form of clumps or clouds. The HI clouds
and clumps have been identified using a thresholding method with three separate
brightness temperature thresholds ($T_b$). Each catalog of HI cloud candidates
shows a power law relationship between the sizes and the velocity dispersions
of the clouds roughly following the Larson Law scaling $\sigma_v \propto
R^{0.5}$, with steeper indices associated with dynamically hot regions. The
clouds in each catalog have roughly constant virial parameters as a function
mass suggesting that that the clouds are all in roughly the same dynamical
state, but the values of the virial parameter are significantly larger than
unity showing that turbulent motions dominate gravity in these clouds. The mass
distribution of the clouds is a power law with differential indices between
-1.6 and -2.0 for the three catalogs. In contrast, the distribution of mean
surface densities is a log-normal distribution.


title:
Influence of experimental context on the development of anhedonia in
  male mice imposed to chronic social stress

abstract:
  Anhedonia is one of the key symptoms of depression in humans. Consumption of
1% sucrose solution supplemented with 0.2% vanillin was studied in two
experimental contexts in male mice living under chronic social stress induced
by daily experience of defeats in agonistic interactions and leading to
development of depression. In the first experiment, vanillin sucrose solution
was made available as an option of water during 10 days to mice living in group
home cages. Then the mice were subjected to social defeat stress and during
stress exposure they were provided with both vanillin sucrose solution and
water using a free two bottles choice paradigm. In the other experiment,
vanillin sucrose solution were first offered to mice after 8 days of exposure
to social defeat stress. Males familiar with vanillin sucrose solution showed
vanillin sucrose preference while experiencing defeat stress: consumption of
vanillin sucrose solution was about 70% of total liquid consumption. However,
the consumption of vanillin sucrose solution per gram of body weight in mice
imposed to social stress during 20 days was significantly lower than in control
males. In the second experiment, males after 8 days of social defeat stress
were found to consume significantly less vanillin sucrose solution as compared
with control males. On average during two weeks of measurements, vanillin
sucrose solution intake was less than 20% of total liquid consumption in males
with symptoms of depression and anxiety. Consumption per gram of body weight
also appeared to be significantly lower than in control group. Influence of the
experimental context on the development of anhedonia, which was measured by the
reduction in sucrose solution intake by chronically stressed male mice, has
been discussed.


title: Comments Brane-World Black Holes and Energy-Momentum Vector

abstract:
  We show that the energy distribution of the brane-world black holes given by
Salti et al. in the context of teleparallel theory is not right. We give the
correct formula of energy of those black hole.


title: Reaction Time of a Group of Physics Students

abstract:
  The reaction time of a group of students majoring in Physics is reported
here. Strong co-relation between fatigue, reaction time and performance have
been seen and may be useful for academicians and administrators responsible of
working out time-tables, course structures, students counsellings etc.


title: Hyperspherical approach to the four-body problem

abstract:
  The four-particle system is the simplest few-body system containing the
fundamental physics involved in ultracold fermionic gases. We have made recent
efforts to solve the quantum four-body problem in the adiabatic hyperspherical
representation. Our approach yields a set of coupled potential curves that can
in turn be solved for all elastic and inelastic processes. These rates may play
an important role in the lifetime of molecules in ultracold fermi gases. We
believe this will lead to a deeper understanding of ultracold fermi systems and
the physics of the BCS-BEC crossover.


title: Lattice bosons in quartic confinement

abstract:
  We present a theoretical study of bose condensation of non-interacting bosons
in finite lattices in quartic potentials in one, two, and three dimensions. We
investigate dimensionality effects and quartic potential effects on single
boson density of energy states, condensation temperature, condensate fraction,
and specific heat. The results obtained are compared with corresponding results
for lattice bosons in harmonic traps.


title: On the harmonic map equation

abstract:
  A generalized harmonic map equation is presented based on the proposed action
functional in the Weyl space (PLA, 135, 315, 1989).


title: The evolution of the cosmic SN rate

abstract:
  We briefly review the contribution of SN rate measurements to the debate on
SN progenitor scenarios. We find that core collapse rates confirms the rapid
evolution of the star formation rate with redshift. After accounting for the
dispersion of SN Ia measurements and uncertainty of the star formation history,
the standard scenarios for SN Ia progenitors appear consistent with all
observational constraints.


title: The Quantum Black-Scholes Equation

abstract:
  Motivated by the work of Segal and Segal on the Black-Scholes pricing formula
in the quantum context, we study a quantum extension of the Black-Scholes
equation within the context of Hudson-Parthasarathy quantum stochastic
calculus. Our model includes stock markets described by quantum Brownian motion
and Poisson process.


title: Limits of PGL(3)-translates of plane curves, I

abstract:
  We classify all possible limits of families of translates of a fixed,
arbitrary complex plane curve. We do this by giving a set-theoretic description
of the projective normal cone (PNC) of the base scheme of a natural rational
map, determined by the curve, from the $P^8$ of 3x3 matrices to the $P^N$ of
plane curves of degree $d$. In a sequel to this paper we determine the
multiplicities of the components of the PNC. The knowledge of the PNC as a
cycle is essential in our computation of the degree of the PGL(3)-orbit closure
of an arbitrary plane curve, performed in our earlier paper "Linear orbits of
arbitrary plane curves".


title:
The high energy emission of GRO J1655-40 as revealed with INTEGRAL
  spectroscopy of the 2005 outburst

abstract:
  We present broadband (3-500 keV) INTEGRAL X-ray spectra and X-ray/optical
light curves of the luminous black hole X-ray transient and relativistic jet
source GRO J1655-40. Our analysis covers four Target of Opportunity
observations of the outburst that started in February 2005. We find that the
high energy emission of GRO J1655-40 can be modelled well with an unbroken
power-law (with photon indices of 1.72+-0.03,2.21+-0.04 for the first and the
second observations, respectively). These correspond to hard and thermal
dominant states, respectively. In contrast to many other black hole spectra,
high energy complexity in the form of a break or cut-off is not required for
the hard state, contrary to previous expectations for this state. We show for
the first time that Comptonization by non-thermal electrons is the dominant
process for the high energy emission in the hard state. We discuss our results
in terms of models for broad-band emission and accretion flows in stellar-mass
black holes.


title:
On reconstruction formulas and algorithms for the thermoacoustic
  tomography

abstract:
  The paper surveys recent progress in establishing uniqueness and developing
inversion formulas and algorithms for the thermoacoustic tomography. In
mathematical terms, one deals with a rather special inverse problem for the
wave equation. In the case of constant sound speed, it can also be interpreted
as a problem concerning the spherical mean transform.


title: Limits of PGL(3)-translates of plane curves, II

abstract:
  Every complex plane curve C determines a subscheme S of the $P^8$ of 3x3
matrices, whose projective normal cone (PNC) captures subtle invariants of C.
In "Limits of PGL(3)-translates of plane curves, I" we obtain a set-theoretic
description of the PNC and thereby we determine all possible limits of families
of plane curves whose general element is isomorphic to C. The main result of
this article is the determination of the PNC as a cycle; this is an essential
ingredient in our computation in "Linear orbits of arbitrary plane curves" of
the degree of the PGL(3)-orbit closure of an arbitrary plane curve, an
invariant of natural enumerative significance.


title: Where post-Newtonian and numerical-relativity waveforms meet

abstract:
  We analyze numerical-relativity (NR) waveforms that cover nine orbits (18
gravitational-wave cycles) before merger of an equal-mass system with low
eccentricity, with numerical uncertainties of 0.25 radians in the phase and
less than 2% in the amplitude; such accuracy allows a direct comparison with
post-Newtonian (PN) waveforms. We focus on one of the PN approximants that has
been proposed for use in gravitational-wave data analysis, the restricted 3.5PN
``TaylorT1'' waveforms, and compare these with a section of the numerical
waveform from the second to the eighth orbit, which is about one and a half
orbits before merger. This corresponds to a gravitational-wave frequency range
of $M\omega = 0.0455$ to 0.1. Depending on the method of matching PN and NR
waveforms, the accumulated phase disagreement over this frequency range can be
within numerical uncertainty. Similar results are found in comparisons with an
alternative PN approximant, 3PN ``TaylorT3''. The amplitude disagreement, on
the other hand, is around 6%, but roughly constant for all 13 cycles that are
compared, suggesting that only 4.5 orbits need be simulated to match PN and NR
waves with the same accuracy as is possible with nine orbits. If, however, we
model the amplitude up to 2.5PN order, the amplitude disagreement is roughly
within numerical uncertainty up to about 11 cycles before merger.


title:
Characterizing synaptic conductance fluctuations in cortical neurons and
  their influence on spike generation

abstract:
  Cortical neurons are subject to sustained and irregular synaptic activity
which causes important fluctuations of the membrane potential (Vm). We review
here different methods to characterize this activity and its impact on spike
generation. The simplified, fluctuating point-conductance model of synaptic
activity provides the starting point of a variety of methods for the analysis
of intracellular Vm recordings. In this model, the synaptic excitatory and
inhibitory conductances are described by Gaussian-distributed stochastic
variables, or colored conductance noise. The matching of experimentally
recorded Vm distributions to an invertible theoretical expression derived from
the model allows the extraction of parameters characterizing the synaptic
conductance distributions. This analysis can be complemented by the matching of
experimental Vm power spectral densities (PSDs) to a theoretical template, even
though the unexpected scaling properties of experimental PSDs limit the
precision of this latter approach. Building on this stochastic characterization
of synaptic activity, we also propose methods to qualitatively and
quantitatively evaluate spike-triggered averages of synaptic time-courses
preceding spikes. This analysis points to an essential role for synaptic
conductance variance in determining spike times. The presented methods are
evaluated using controlled conductance injection in cortical neurons in vitro
with the dynamic-clamp technique. We review their applications to the analysis
of in vivo intracellular recordings in cat association cortex, which suggest a
predominant role for inhibition in determining both sub- and supra-threshold
dynamics of cortical neurons embedded in active networks.


title: Finite-size effects in roughness distribution scaling

abstract:
  We study numerically finite-size corrections in scaling relations for
roughness distributions of various interface growth models. The most common
relation, which considers the average roughness $<w_2>$ as scaling factor, is
not obeyed in the steady states of a group of ballistic-like models in 2+1
dimensions, even when very large system sizes are considered. On the other
hand, good collapse of the same data is obtained with a scaling relation that
involves the root mean square fluctuation of the roughness, which can be
explained by finite-size effects on second moments of the scaling functions. We
also obtain data collapse with an alternative scaling relation that accounts
for the effect of the intrinsic width, which is a constant correction term
previously proposed for the scaling of $<w_2>$. This illustrates how
finite-size corrections can be obtained from roughness distributions scaling.
However, we discard the usual interpretation that the intrinsic width is a
consequence of high surface steps by analyzing data of restricted
solid-on-solid models with various maximal height differences between
neighboring columns. We also observe that large finite-size corrections in the
roughness distributions are usually accompanied by huge corrections in height
distributions and average local slopes, as well as in estimates of scaling
exponents. The molecular-beam epitaxy model of Das Sarma and Tamborenea in 1+1
dimensions is a case example in which none of the proposed scaling relations
works properly, while the other measured quantities do not converge to the
expected asymptotic values. Thus, although roughness distributions are clearly
better than other quantities to determine the universality class of a growing
system, it is not the final solution for this task.


title: Geometrically frustrated magnetic behavior of Sr3NiRhO6 and Sr3NiPtO6

abstract:
  The results of ac and dc magnetic susceptibility isothermal magnetization and
heat-capacity measurements as a function of temperature (T) are reported for
Sr3NiRhO6 and Sr3NiPtO6 containing magnetic chains arranged in a triangular
fashion in the basal plane and crystallizing in K4CdCl6-derived rhombohedral
structure. The results establish that both the compounds are magnetically
frustrated, however in different ways. In the case of the Rh compound, the
susceptibility data reveal that there are two magnetic transitions, one in the
range 10 -15 K and the other appearing as a smooth crossover near 45 K, with a
large frequency dependence of ac susceptibility in the range 10 to 40 K; in
addition, the features in C(T) are smeared out at these temperatures. The
magnetic properties are comparable to those of previously known few compounds
with partially disordered antiferromagnetic structure. On the other hand, for
Sr3NiPtO6, there is no evidence for long-range magnetic ordering down to 1.8 K
despite large value of paramagnetic Curie temperature.


title: Superconducting behavior of the solid solution, Y2Pd(1-x)Pt(x)Ge3

abstract:
  The compound Y2PdGe3 was earlier reported by us to be one of the very few
ternary superconducting compounds (T_c= 3 K) belonging to the same structure as
that of MgB2. Here we report the results of electrical resistivity,
magnetization and heat capacity measurements at low temperatures on the solid
solution with a nominal starting composition, Y2Pd(1-x)Pt(x)Ge3, to understand
the influence of gradual replacement of Pd by Pt on T_c. The superconducting
properties of this solution is distinctly interesting in the sense that the Tc
varies monotonically with increasing x in sharp contrast to the non-monotonic
variation for other isostructural solid solutions reported recently.


title: The Geometer's Toolkit to String Compactifications

abstract:
  These lecture notes are meant to serve as an introduction to some geometric
constructions and techniques (in particular the ones of toric geometry) often
employed by the physicist working on string theory compactifications. The
emphasis is wholly on the geometry side, not on the physics.
  The treated topics include toroidal orbifolds, methods of toric geometry,
desinglularization of toroidal orbifolds and their orientifold quotients.


title: Compactified moduli of projective bundles

abstract:
  We present a method for compactifying stacks of $\PGL_n$-torsors (Azumaya
algebras) on algebraic spaces. In particular, when the ambient space is a
smooth projective surface we use our methods to show that various moduli spaces
are irreducible and carry natural virtual fundamental classes. We also prove a
version of the Skolem-Noether theorem for certain algebra objects in the
derived category, which allows us to give an explicit description of the
boundary points in our compactified moduli problem.


title: Entrelacement d'alg\`ebres de Lie [Wreath products for Lie algebras]

abstract:
  Full details are given for the definition and construction of the wreath
product of two arbitrary Lie algebras, in the hope that it can lead to the
definition of a suitable Lie group to be the wreath product of two given Lie
groups. In the process, quite a few new notions are needed, and introduced.
Such are, for example : Formal series with variables in a vector space and
coefficients in some other vector space. Derivation of a formal series relative
to another formal series. The Lie algebra of a vector space. Formal actions of
Lie algebras over vector spaces. The basic formal action of a Lie algebra over
itself (as a formal version of the analytic aspect of the infinitesimal
operation law of a Lie groupuscule). More generally, the wreath product of two
Lie algebras is defined, relative to a formal action of the second onto an
arbitrary vector space. Main features are : A description of the triangular
actions of wreath products over product vector spaces, and a Kaloujnine-Krasner
type theorem : In essence, it says that all Lie extensions of a given Lie
algebra by another Lie algebra are, indeed, subalgebras of their wreath
product.


title:
Non-unique ergodicity, observers' topology and the dual algebraic
  lamination for $\R$-trees

abstract:
  We continue in this article the study of laminations dual to very small
actions of a free group F on R-trees. We prove that this lamination determines
completely the combinatorial structure of the R-tree (the so-called observers'
topology). On the contrary the metric is not determined by the lamination, and
an R-tree may be equipped with different metrics which have the same observers'
topology.


title: When Did Cosmic Acceleration Start ?

abstract:
  A precise determination, and comparison, of the epoch of the onset of cosmic
acceleration, at redshift z_acc, and of dark energy domination, at z_eq,
provides an interesting measure with which to parameterize dark energy models.
By combining several cosmological datasets we place constraints on the redshift
and age of cosmological acceleration. For a Lambda-CDM model, we find the
constraint z_acc=0.76\pm0.10 at 95% c.l., occurring 6.7\pm0.4 Gyrs ago.
Allowing a constant equation of state but different from -1 changes the
constraints to z_acc=0.81\pm0.12 (6.9\pm0.5 Gyrs ago) and
z_eq=0.48\pm0.14(4.9\pm0.9 Gyrs ago), while dynamical models markedly increase
the error on the constraints with z_acc=0.81\pm0.30 (6.8\pm1.4 Gyrs ago) and
z_eq=0.44\pm0.20 (4.5\pm1.0 Gyrs ago). Unified dark energy models as Silent
Quartessence yield: z_acc=0.80\pm0.16 (6.8\pm0.6 Gyrs ago).


title: The Dirac system on the Anti-de Sitter Universe

abstract:
  We investigate the global solutions of the Dirac equation on the
Anti-de-Sitter Universe. Since this space is not globally hyperbolic, the
Cauchy problem is not, {\it a priori}, well-posed. Nevertheless we can prove
that there exists unitary dynamics, but its uniqueness crucially depends on the
ratio beween the mass $M$ of the field and the cosmological constant
$\Lambda>0$ : it appears a critical value, $\Lambda/12$, which plays a role
similar to the Breitenlohner-Freedman bound for the scalar fields. When
$M^2\geq \Lambda/12$ there exists a unique unitary dynamics. In opposite, for
the light fermions satisfying $M^2<\Lambda/12$, we construct several asymptotic
conditions at infinity, such that the problem becomes well-posed. In all the
cases, the spectrum of the hamiltonian is discrete. We also prove a result of
equipartition of the energy.


title:
Coupling of Optical Lumped Nanocircuit Elements and Effects of
  Substrates

abstract:
  We present here a model for the coupling among small nanoparticles excited by
an optical electric field in the framework of our optical lumped nanocircuit
theory [N. Engheta, A. Salandrino, and A. Alu Phys. Rev. Lett. 95, 095504
(2005)]. We derive how this coupling affects the corresponding nanocircuit
model by adding controlled sources that depend on the optical voltages applied
on the coupled particles. With the same technique, we can model also the
presence of a substrate underneath nanocircuit elements, relating its presence
to the coupling with a properly modeled image nanoparticle. These results are
of importance in the understanding and the design of complex optical
nanocircuits at infrared and optical frequencies.


title:
A model for learning to segment temporal sequences, utilizing a mixture
  of RNN experts together with adaptive variance

abstract:
  This paper proposes a novel learning method for a mixture of recurrent neural
network (RNN) experts model, which can acquire the ability to generate desired
sequences by dynamically switching between experts. Our method is based on
maximum likelihood estimation, using a gradient descent algorithm. This
approach is similar to that used in conventional methods; however, we modify
the likelihood function by adding a mechanism to alter the variance for each
expert. The proposed method is demonstrated to successfully learn Markov chain
switching among a set of 9 Lissajous curves, for which the conventional method
fails. The learning performance, analyzed in terms of the generalization
capability, of the proposed method is also shown to be superior to that of the
conventional method. With the addition of a gating network, the proposed method
is successfully applied to the learning of sensory-motor flows for a small
humanoid robot as a realistic problem of time series prediction and generation.


title: Constructing a maximum utility slate of on-line advertisements

abstract:
  We present an algorithm for constructing an optimal slate of sponsored search
advertisements which respects the ordering that is the outcome of a generalized
second price auction, but which must also accommodate complicating factors such
as overall budget constraints. The algorithm is easily fast enough to use on
the fly for typical problem sizes, or as a subroutine in an overall
optimization.


title: Dealing with delicate issues in waveforms calculations

abstract:
  We revisit the calculation of gravitational radiation through the use of Weyl
scalars. We point out several possible problems arising from gauge and tetrad
ambiguities and ways to address them. Our analysis indicates how, relatively
simple corrections can be introduced to remove these ambiguities.


title:
Accretion vs colliding wind models for the gamma-ray binary LS I +61
  303: an assessment

abstract:
  LS I +61 303 is a puzzling Be/X-ray binary with variable gamma-ray emission
at up TeV energies. The nature of the compact object and the origin of the
high-energy emission are unclear. One family of models invokes particle
acceleration in shocks from the collision between the B-star wind and a
relativistic pulsar wind, while another centers on a relativistic jet powered
by accretion. Recent high-resolution radio observations showing a putative
"cometary tail" pointing away from the Be star near periastron have been cited
as support for the pulsar-wind model. We wish here to carry out a quantitative
assessment of these competing models for this extraordinary source. We apply a
3D SPH code for dynamical simulations of both the pulsar-wind-interaction and
accretion-jet models. The former yields a description of the shape of the
wind-wind interaction surface. The latter provides an estimation of the
accretion rate. The results allow critical evaluation of how the two distinct
models confront the data in various wavebands under a range of conditions. When
one accounts for the 3D dynamical wind interaction under realistic constraints
for the relative strength of the B-star and pulsar winds, the resulting form of
the interaction front does not match the putative "cometary tail" claimed from
radio observations. On the other hand, dynamical simulations of the
accretion-jet model indicate that the orbital phase variation of accretion
power includes a secondary broad peak well away from periastron, thus providing
a plausible way to explain the observed TeV gamma ray emission toward apastron.
We conclude that the colliding-wind model is not clearly established for LS I
+61 303, while the accretion-jet model can reproduce many key characteristics
of the observed TeV gamma-ray emission.


title:
Detailed study of the GRB 030329 radio afterglow deep into the
  non-relativistic phase

abstract:
  We explore the physics behind one of the brightest radio afterglows ever, GRB
030329, at late times when the jet is non-relativistic. We determine the
physical parameters of the blast wave and its surroundings, in particular the
index of the electron energy distribution, the energy of the blast wave, and
the density (structure) of the circumburst medium. We then compare our results
with those from image size measurements. We observed the GRB 030329 radio
afterglow with the Westerbork Synthesis Radio Telescope and the Giant Metrewave
Radio Telescope at frequencies from 325 MHz to 8.4 GHz, spanning a time range
of 268-1128 days after the burst. We modeled all the available radio data and
derived the physical parameters. The index of the electron energy distribution
is p=2.1, the circumburst medium is homogeneous, and the transition to the
non-relativistic phase happens at t_NR ~ 80 days. The energy of the blast wave
and density of the surrounding medium are comparable to previous findings. Our
findings indicate that the blast wave is roughly spherical at t_NR, and they
agree with the implications from the VLBI studies of image size evolution. It
is not clear from the presented dataset whether we have seen emission from the
counter jet or not. We predict that the Low Frequency Array will be able to
observe the afterglow of GRB 030329 and many other radio afterglows,
constraining the physics of the blast wave during its non-relativistic phase
even further.


title:
Thermodynamics and the virial expansion for trapped fluids in arbitrary
  external potentials

abstract:
  We present the full thermodynamics of a fluid confined by an arbitrary
external potential based on the virial expansion of the grand potential. The
fluid may be classical or quantum and it is assumed that interatomic
interactions are pairwise additive. We indicate how the appropriate
"generalized" volume and pressure variables, that replace the usual volume and
hydrostatic pressure, emerge for a given confining potential in the
thermodynamic limit. A discussion of the physical meaning and of the
measurement of these variables is presented. We emphasize that this treatment
yields the correct equation of state of the fluid and we give its virial
expansion. We propose an experiment to measure the heat capacity, so that with
this quantity and the equation of state, the complete thermodynamics of the
system may be extracted. As a corollary, we find that the so-called {\it local
density approximation} for these systems follows in the thermodynamic limit,
although we also point out that it cannot be used indiscriminately for all
local variables. Along the text we discuss the relevance of these findings in
the description of the currently confined ultracold gases.


title: GRB 030329: 3 years of radio afterglow monitoring

abstract:
  Radio observations of gamma-ray burst (GRB) afterglows are essential for our
understanding of the physics of relativistic blast waves, as they enable us to
follow the evolution of GRB explosions much longer than the afterglows in any
other wave band. We have performed a three-year monitoring campaign of GRB
030329 with the Westerbork Synthesis Radio Telescopes (WSRT) and the Giant
Metrewave Radio Telescope (GMRT). Our observations, combined with observations
at other wavelengths, have allowed us to determine the GRB blast wave physical
parameters, such as the total burst energy and the ambient medium density, as
well as investigate the jet nature of the relativistic outflow. Further, by
modeling the late-time radio light curve of GRB 030329, we predict that the
Low-Frequency Array (LOFAR, 30-240 MHz) will be able to observe afterglows of
similar GRBs, and constrain the physics of the blast wave during its
non-relativistic phase.


title: GRB 030329: three years of radio afterglow monitoring

abstract:
  Radio observations of gamma-ray burst (GRB) afterglows are essential for our
understanding of the physics of relativistic blast waves, as they enable us to
follow the evolution of GRB explosions much longer than the afterglows in any
other wave band. We have performed a three-year monitoring campaign of GRB
030329 with the Westerbork Synthesis Radio Telescopes (WSRT) and the Giant
Metrewave Radio Telescope (GMRT). Our observations, combined with observations
at other wavelengths, have allowed us to determine the GRB blast wave physical
parameters, such as the total burst energy and the ambient medium density, as
well as investigate the jet nature of the relativistic outflow. Further, by
modeling the late-time radio light curve of GRB 030329, we predict that the Low
Frequency Array (LOFAR, 30-240 MHz) will be able to observe afterglows of
similar GRBs, and constrain the physics of the blast wave during its
non-relativistic phase.


title:
Possible astronomical references in the planning of the Great Hopewell
  Road

abstract:
  The possible existence of astronomical references in the planning of the
so-called Great Hopewell Road, a 90 Kilometres straight road composed of two
parallel earthen embankments which, according to recent surveys, likely
connected the Hopewell ceremonial centres of Newark and Chillicothe, Ohio, are
investigated. It turns out that a very peculiar, although simple, set of
astronomical alignments took place in connection with the road during possible
periods of its construction. The possibility of a non-fortuitous connection is
thus proposed and analysed.


title:
The oscillation stability problem for the Urysohn sphere: A
  combinatorial approach

abstract:
  We study the oscillation stability problem for the Urysohn sphere, an analog
of the distortion problem for $\ell_2$ in the context of the Urysohn space
$\Ur$. In particular, we show that this problem reduces to a purely
combinatorial problem involving a family of countable ultrahomogeneous metric
spaces with finitely many distances.


title: Hopf Algebras of Heap Ordered Trees and Permutations

abstract:
  It is known that there is a Hopf algebra structure on the vector space with
basis all heap-ordered trees. We give a new bialgebra structure on the space
with basis all permutations and show that there is a direct bialgebra
isomorphism between the Hopf algebra of heap-ordered trees and the bialgebra of
permutations.


title: N = 4 Superfiel Phase Space Coordinates and Hamiltonian Quantization

abstract:
  The N = 4 superfield phase space coordinates are given in the harmonic
superspace. The expressions of the N = 4 classical equations of motion are
determined in terms of the spinorial and harmonic supercharges. Furthermore,
the N = 4 supersymmetric actions are obtained by means of the fermionic and
harmonic functionals. On the other hand, the Hamiltonian quantization is
studied by performing the N = 4 supersymmetric action in harmonic subspace in
terms of analytic N = 4 superfield phase space coordinates.


title:
Solidity of viscous liquids. V. Long-wavelength dominance of the
  dynamics

abstract:
  This paper is the fifth in a series exploring the physical consequences of
the solidity of glass-forming liquids. Paper IV proposed a model where the
density field is described by a time-dependent Ginzburg-Landau equation of the
nonconserved type with rates in $k$ space of the form $\Gamma_0+Dk^2$. The
model assumes that $D\gg\Gamma_0a^2$ where $a$ is the average intermolecular
distance; this inequality expresses a long-wavelength dominance of the dynamics
which implies that the Hamiltonian (free energy) to a good approximation may be
taken to be ultralocal. In the present paper we argue that this is the simplest
model consistent with the following three experimental facts: 1) Viscous
liquids approaching the glass transition do not develop long-range order; 2)
The glass has lower compressibility than the liquid; 3) The alpha process
involves several decades of relaxation times shorter than the mean relaxation
time. The paper proceeds to list six further experimental facts characterizing
equilibrium viscous liquid dynamics and shows that these are readily understood
in terms of the model; some are direct consequences, others are quite natural
when viewed in light of the model.


title:
Note on: Considering the Case for Biodiversity Cycles: Reexamining the
  Evidence for Periodicity in the Fossil Record, by Lieberman and Melott, arXiv
  preprint 0704.2896

abstract:
  Lieberman and Melott built their recent arXiv preprint 0704.2896 on my
published paper and (a preprint of) a subsequent comment by Liebermans
associate Cornette. But had this group waited for the Cornette comment to
actually appear in print together with the expected Reply, they would have
learned that his comment exposes Cornettes confusion that likely was due to
journal misprint of my figure. Thus 0704.2896 is baseless. Despite receiving
the extended Reply with Errata, these authors still fail to recognize that
detrending of paleontological records-which they erroneously promote as a
must-is an arbitrary rather than a universal operation.


title: On a Smale Theorem and Nonhomogeneous Equilibria in Cooperative Systems

abstract:
  A standard result by Smale states that n dimensional strongly cooperative
dynamical systems can have arbitrary dynamics when restricted to unordered
invariant hyperspaces. In this paper this result is extended to the case when
all solutions of the strongly cooperative system are bounded and converge
towards one of only two equilibria outside of the hyperplane.
  An application is given in the context of strongly cooperative systems of
reaction diffusion equations. It is shown that such a system can have a
continuum of spatially inhomogeneous steady states, even when all solutions of
the underlying reaction system converge to one of only three equilibria.


title:
Constraints on Galaxy Structure and Evolution from the Light of Nearby
  Systems

abstract:
  We review knowledge of galaxy structures obtained by their emitted light and
in the local universe where they can be studied in great detail. We discuss the
shapes of, and stellar motions within, galaxies, compositional clues derived
from their spectra, and what luminous matter implies about their dark matter
content. Implications on the current theory of hierarchical galaxy formation
are explored.


title:
An explicit construction of the Quillen homotopical category of dg Lie
  algebras

abstract:
  Let $\g_1$ and $\g_2$ be two dg Lie algebras, then it is well-known that the
$L_\infty$ morphisms from $\g_1$ to $\g_2$ are in 1-1 correspondence to the
solutions of the Maurer-Cartan equation in some dg Lie algebra
$\Bbbk(\g_1,\g_2)$. Then the gauge action by exponents of the zero degree
component $\Bbbk(\g_1,\g_2)^0$ on $MC\subset\Bbbk(\g_1,\g_2)^1$ gives an
explicit "homotopy relation" between two $L_\infty$ morphisms. We prove that
the quotient category by this relation (that is, the category whose objects are
$L_\infty$ algebras and morphisms are $L_\infty$ morphisms modulo the gauge
relation) is well-defined, and is a localization of the category of dg Lie
algebras and dg Lie maps by quasi-isomorphisms. As localization is unique up to
an equivalence, it is equivalent to the Quillen-Hinich homotopical category of
dg Lie algebras [Q1,2], [H1,2]. Moreover, we prove that the Quillen's concept
of a homotopy coincides with ours. The last result was conjectured by
V.Dolgushev [D].


title:
Transients from initial conditions based on Lagrangian perturbation
  theory in N-body simulations

abstract:
  We explore the initial conditions for cosmological N-body simulations
suitable for calculating the skewness and kurtosis of the density field. In
general, the initial conditions based on the perturbation theory (PT) provide
incorrect second-order and higher-order growth. These errors implied by the use
of the perturbation theory to set up the initial conditions in N-body
simulations are called transients. Unless these transients are completely
suppressed compared with the dominant growing mode, we can not reproduce the
correct evolution of cumulants with orders higher than two, even though there
is no problem with the numerical scheme. We investigate the impact of
transients on the observable statistical quantities by performing $N$-body
simulations with initial conditions based on Lagrangian perturbation theory
(LPT). We show that the effects of transients on the kurtosis from the initial
conditions, based on second-order Lagrangian perturbation theory (2LPT) have
almost disappeared by $z\sim5$, as long as the initial conditions are set at $z
> 30$. This means that for practical purposes, the initial conditions based on
2LPT are accurate enough for numerical calculations of skewness and kurtosis.


title: Geometric mesoscopic correlations in quasi-one dimension

abstract:
  We study analytically and numerically field/intensity correlations in wave
transport through volume-disordered waveguide. The obtained channel and spacial
correlations deviate from those found in framework of
Dorokhov-Mello-Pereyra-Kumar (DMPK) formalism, that we relate to
inapplicability of equivalent channel approximation in DMPK. We show that this
can be remedied by introducing boundary correction -- an escape function which
depends on the waveguide geometry -- that describes wave transport near a
boundary between random medium and free space. We obtain the expressions for
field/intensity channel and spacial correlation functions which agree with the
numerics and are consistent with the perturbative expressions in slab geometry
as well as experiments conducted in Q1D.


title: Can aerosols be trapped in open flows?

abstract:
  The fate of aerosols in open flows is relevant in a variety of physical
contexts. Previous results are consistent with the assumption that such
finite-size particles always escape in open chaotic advection. Here we show
that a different behavior is possible. We analyze the dynamics of aerosols both
in the absence and presence of gravitational effects, and both when the
dynamics of the fluid particles is hyperbolic and nonhyperbolic. Permanent
trapping of aerosols much heavier than the advecting fluid is shown to occur in
all these cases. This phenomenon is determined by the occurrence of multiple
vortices in the flow and is predicted to happen for realistic particle-fluid
density ratios.


title: A note on Poisson homogeneous spaces

abstract:
  We identify the cotangent bundle Lie algebroid of a Poisson homogeneous space
G/H of a Poisson Lie group G as a quotient of a transformation Lie algebroid
over G. As applications, we describe the modular vector fields of G/H, and we
identify the Poisson cohomology of G/H with coefficients in powers of its
canonical line bundle with relative Lie algebra cohomology of the Drinfeld Lie
algebra associated to G/H. We also construct a Poisson groupoid over G/H which
is symplectic near the identity section. This note serves as preparation for
forthcoming papers, in which we will compute explicitly the Poisson cohomology
and study their symplectic groupoids for certain examples of Poisson
homogeneous spaces related to semi-simple Lie groups.


title:
Supersymmetric Hamiltonian Approach to Edge Excitations in $\nu = 5/2$
  Fractional Quantum Hall Effect

abstract:
  A supersymmetric Hamiltonian is constructed for the edge excitations of the
Moore-Read (Pfaffian) like state, which is a realization of the N=2
supersymmetric CS model. Fermionic generators and their conjugates are
introduced to deal with the fermion pairing, whose condensation form a BCS like
state. After Bogoliubov transformation, a N=2 supersymmetric and
nonrelativistic Hamiltonian is found to take a known form, which is integrable.
The main difference between the Moore-Read state and our BCS like state is that
the number of fermion pairs in our formalism is not fixed. However, we have
also found that the excited states in our model looks similar but not exactly
the same as Moore and Read's.


title:
Verification theorem and construction of $\epsilon$-optimal controls for
  control of abstract evolution equations

abstract:
  We study several aspects of the dynamic programming approach to optimal
control of abstract evolution equations, including a class of semilinear
partial differential equations. We introduce and prove a verification theorem
which provides a sufficient condition for optimality. Moreover we prove sub-
and superoptimality principles of dynamic programming and give an explicit
construction of $\epsilon$-optimal controls.


title:
Cluster abundances and S-Z power spectra: effects of non-Gaussianity and
  early dark energy

abstract:
  In the standard Lambda CDM cosmological model with a Gaussian primordial
density fluctuation field, the relatively low value of the mass variance
parameter (sigma_8=0.74{+0.05}{-0.06}, obtained from the WMAP 3-year data)
results in a reduced likelihood that the measured level of CMB anisotropy on
the scales of clusters is due to the Sunyaev-Zeldovich (S-Z) effect. To assess
the feasibility of producing higher levels of S-Z power, we explore two
alternative models which predict higher cluster abundance. In the first model
the primordial density field has a chi^2_1 distribution, whereas in the second
an early dark energy component gives rise to the desired higher cluster
abundance. We carry out the necessary detailed calculations of the levels of
S-Z power spectra, cluster number counts, and angular 2-point correlation
function of clusters, and compare (in a self-consistent way) their predicted
redshift distributions. Our results provide a sufficient basis upon which the
viability of the three models may be tested by future high quality
measurements.


title: A Study in Depth of f0(1370)

abstract:
  Claims have been made that f0(1370) does not exist. The five primary sets of
data requiring its existence are refitted. Major dispersive effects due to the
opening of the 4pi threshold are included for the first time; the sigma -> 4pi
amplitude plays a strong role. Crystal Barrel data on pbar-p -> 3pizero at rest
require f0(1370) signals of at least 32 and 33 standard deviations in 1S0 and
3P1 annihilation respectively. Furthermore, they agree within 5 MeV for mass
and width. Data on pbar-p -> eta-eta-pizero agree and require at least a 19
standard deviation contribution. This alone is sufficient to demonstrate the
existence of f0(1370). BES II data for J/Psi -> phi-pi-pi contain a visible
f0(1370) signal > 8 standard devations. In all cases, a resonant phase
variation is required. The possibility of a second pole in the sigma amplitude
due to the opening of the 4pi channel is excluded. Cern-Munich data for pi-pi
elastic scattering are fitted well with the inclusion of some mixing between
sigma, f0(1370) and f0(1500). The pi-pi widths for f2(1565), rho3(1690),
rho3(1990) and f4(2040) are determined.


title: Low-temperature electron dephasing time in AuPd revisited

abstract:
  Ever since the first discoveries of the quantum-interference transport in
mesoscopic systems, the electron dephasing times, $\tau_\phi$, in the
concentrated AuPd alloys have been extensively measured. The samples were made
from different sources with different compositions, prepared by different
deposition methods, and various geometries (1D narrow wires, 2D thin films, and
3D thickfilms) were studied. Surprisingly, the low-temperature behavior of
$\tau_\phi$ inferred by different groups over two decades reveals a systematic
correlation with the level of disorder of the sample. At low temperatures,
where $\tau_\phi$ is (nearly) independent of temperature, a scaling
$\tau_\phi^{\rm max} \propto D^{-\alpha}$ is found, where $tau_\phi^{\rm max}$
is the maximum value of $\tau_\phi$ measured in the experiment, $D$ is the
electron diffusion constant, and the exponent $\alpha$ is close to or slightly
larger than 1. We address this nontrivial scaling behavior and suggest that the
most possible origin for this unusual dephasing is due to dynamical structure
defects, while other theoretical explanations may not be totally ruled out.


title:
Interacting like charges in Landau levels: Planar geometry, symmetries,
  and effective quasiparticles

abstract:
  We consider a system of two interacting particles with like but unequal
charges in a magnetic field in the planar geometry. We construct a complete
basis of states compatible with both the axial symmetry and magnetic
translations. The basis is obtained using a canonical transformation that
generates effective quasiparticles with modified interactions. We establish a
connection of this transformation with the SU(2) algebra and make use of the
SU(2) Baker-Campbell-Hausdorff formulas for evaluating the interaction matrix
elements. We calculate analytically the eigenenergies of the problem (Haldane
pseudopotentials) in the first few Landau levels for a relatively wide class of
interaction potentials.


title:
A Class of Partially Solvable Two-Dimensional Quantum Models with
  Periodic Potentials

abstract:
  The supersymmetrical approach is used to analyse a class of two-dimensional
quantum systems with periodic potentials. In particular, the method of
SUSY-separation of variables allowed us to find a part of the energy spectra
and the corresponding wave functions (partial solvability) for several models.
These models are not amenable to conventional separation of variables, and they
can be considered as two-dimensional generalizations of Lame, associated Lame,
and trigonometric Razavy potentials. All these models have the symmetry
operators of fourth order in momenta, and one of them (the Lame potential)
obeys the property of self-isospectrality.

categories: hep-th cond-mat.mes-hall math-ph math.MP quant-ph


title:
Spectroscopy and multiband photometry of the afterglow of intermediate
  duration gamma-ray burst 040924 and its host galaxy

abstract:
  We present optical photometry and spectroscopy of the afterglow and host
galaxy of gamma-ray burst 040924. This GRB had a rather short duration of T90
~2.4s, and a well sampled optical afterglow light curve. We aim to use this
dataset to find further evidence that this burst is consistent with a massive
star core-collapse progenitor. We combine the afterglow data reported here with
data taken from the literature and compare the host properties with survey
data. We find that the global behaviour of the optical afterglow is well fit by
a broken power-law, with a break at ~0.03 days. We determine the redshift z =
0.858 +/- 0.001 from the detected emission lines in our spectrum. Using the
spectrum and photometry we derive global properties of the host, showing it to
have similar properties to long GRB hosts. We detect the [Ne III] emission line
in the spectrum, and compare the fluxes of this line of a sample of 15 long GRB
host galaxies with survey data, showing the long GRB hosts to be comparable to
local metal-poor emission line galaxies in their [Ne III] emission. We fit the
supernova bump accompanying this burst, and find that it is similar to other
long GRB supernova bumps, but fainter. All properties of GRB 040924 are
consistent with an origin in the core-collapse of a massive star: the
supernova, the spectrum and SED of the host and the afterglow.


title:
Southern wide very low-mass stars and brown dwarfs in resolved binary
  and multiple systems

abstract:
  The results of the Koenigstuhl survey in the Southern Hemisphere are
presented. I have searched for common-proper motion companions to 173 field
very low-mass stars and brown dwarfs with spectral types > M5.0V and magnitudes
J <= 14.5 mag. I have measured for the first time the common-proper motion of
two new wide systems containing very low-mass components, Koenigstuhl 2 AB and
3 A-BC. Together with Koenigstuhl 1 AB and 2M0126-50AB, they are among the
widest systems in their respective classes (r = 450-11900 AU). Koenigstuhl 3
A-BC contains a well-known F8V star and a M8.0+L3.0V tight binary. I have
determined the minimum frequency of field wide multiples (r > 100 AU) with
late-type components at 5.0+/-1.8 % and the frequency of field wide late-type
binaries with mass ratios q > 0.5 at 1.2+/-0.9 %. These values represent a key
diagnostic of evolution history and low-mass star and brown-dwarf formation
scenarios. Additionally, the proper motions of 76 field very low-mass dwarfs
are measured here for the first time.


title: The Two-State Vector Formalism

abstract:
  The two-state vector formalism (TSVF), the time-symmetric description of the
standard quantum mechanics originated by Aharonov, Bergmann and Lebowitz is
reviewed. The TSVF describes a quantum system at a particular time by two
quantum states: the usual one, evolving forward in time, defined by the results
of a complete measurement at the earlier time, and by the quantum state
evolving backward in time, defined by the results of a complete measurement at
a later time.


title: Weak Value and Weak Measurements

abstract:
  The weak value of a variable O is a description of an effective interaction
with that variable in the limit of weak coupling. It is particularly important
for a pre- and post-selected quantum system.


title:
Improved quark mass density- dependent model with quark-sigma meson and
  quark-omega meson couplings

abstract:
  An improved quark mass density- dependent model with the non-linear scalar
sigma field and the $\omega$-meson field is presented. We show that the present
model can describe saturation properties, the equation of state, the
compressibility and the effective nuclear mass of nuclear matter under mean
field approximation successfully. The comparison of the present model and the
quark-meson coupling model is addressed.