title: Regge Exchange Contribution to Deeply Virtual Compton Scattering

abstract:
  Recently we have shown that exclusive QCD photon-induced reactions at low
Mandelstam-t are best described by Regge exchanges in the entire scaling
region, and not only for low values of Bjorken-x. In this paper we explore this
crucial Regge behavior in Deeply Virtual Compton Scattering from the point of
view of collinear factorization, with the proton tensor written in terms of
Generalized Parton Distributions, and we reproduce this feature. Thus it
appears that in the Bjorken limit, a large class of hard, low-t exclusive
processes are more sensitive to the meson cloud of the proton than to its
fundamental quark structure. These process will then be described most
efficiently by process-dependent Regge Exclusive Amplitudes rather than by
universal Generalized Parton Distributions. We introduce such Regge Exclusive
Amplitudes for Deeply Virtual Compton Scattering.


title:
Partial restoration of factorization and universality in presence of
  factorization breaking interactions in hadronic hard scattering processes

abstract:
  Recent works have discussed the violation of factorization and universality
in hadronic hard scattering processes aimed at measurements of T-odd
distributions. We use simple arguments to show that it is possible to restore
an approximate factorization involving T-odd contributions if the factorization
breaking interactions present a frequency spectrum dominated by by a narrow and
regular peak whose maximum value corresponds to a respected factorization.


title: Graph-Based Decoding in the Presence of ISI

abstract:
  We propose an approximation of maximum-likelihood detection in ISI channels
based on linear programming or message passing. We convert the detection
problem into a binary decoding problem, which can be easily combined with LDPC
decoding. We show that, for a certain class of channels and in the absence of
coding, the proposed technique provides the exact ML solution without an
exponential complexity in the size of channel memory, while for some other
channels, this method has a non-diminishing probability of failure as SNR
increases. Some analysis is provided for the error events of the proposed
technique under linear programming.


title: Charm Dalitz Analyses

abstract:
  A review of recent experimental results of Dalitz analyses of charmed meson
decays into three-body final states is presented. These analyses can help in
understanding the strong interaction dynamics leading to the observed light
mesons spectrum (low mass scalar $\sigma$, $f_0(980)$, $a_0(980)$). A model for
the decay amplitude into such states is very important for the extraction of
the angle $\gamma$ of the CKM unitarity triangle. Implications for such
measurement are discussed.


title: Euler Scheme and Tempered Distributuions

abstract:
  Given a smooth R^d-valued diffusion, we study how fast the Euler scheme with
time step 1/n converges in law. To be precise, we look for which class of test
functions f the approximate expectation E[f(X^{n,x}_1)] converges with speed
1/n to E[f(X^x_1)]. If X is uniformly elliptic, we show that this class
contains all tempered distributions, and all measurable functions with
exponential growth. We give applications to option pricing and hedging, proving
numerical convergence rates for prices, deltas and gammas.


title:
Where are the edge-states near the quantum point contacts? A
  self-consistent approach

abstract:
  In this work, we calculate the current distribution, in the close vicinity of
the quantum point contacts (QPCs), taking into account the Coulomb interaction.
In the first step, we calculate the bare confinement potential of a generic QPC
and, in the presence of a perpendicular magnetic field, obtain the positions of
the incompressible edge states (IES) taking into account electron-electron
interaction within the Thomas-Fermi theory of screening. Using a local version
of the Ohm's law, together with a relevant conductivity model, we also
calculate the current distribution. We observe that, the imposed external
current is confined locally into the incompressible strips. Our calculations
demonstrate that, the inclusion of the electron-electron interaction, strongly
changes the general picture of the transport through the QPCs.


title: CALICE Report to the Calorimeter R&D Review Panel

abstract:
  The report describes the status of the calorimeter R&D for ILC detector
performed in the CALICE collaboration. This status has been presented to the
review panel at the LCWS07 workshop at DESY in June 2007.


title:
Analytical results for stochastically growing networks: connection to
  the zero range process

abstract:
  We introduce a stochastic model of growing networks where both, the number of
new nodes which joins the network and the number of connections, vary
stochastically. We provide an exact mapping between this model and zero range
process, and use this mapping to derive an analytical solution of degree
distribution for any given evolution rule. One can also use this mapping to
infer about a possible evolution rule for a given network. We demonstrate this
for protein-protein interaction (PPI) network for Saccharomyces Cerevisiae.


title: Top Quark Physics at the LHC

abstract:
  The Large Hadron Collider (LHC) is expected to provide proton-proton
collisions at a centre-of-mass energy of 14 TeV, yielding millions of of top
quark events. The top-physics potential of the two general purpose experiments,
ATLAS and CMS, is discussed according to state-of-the-art simulation of both
physics and detectors. An overview is given of the most important results with
emphasis on the expected improvements in our understanding of physics connected
to the top quark.


title:
Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates
  IV: The Puzzle of the Extremely Red OGLE-TR-82 Primary Solved

abstract:
  We present precise new V, I, and K-band photometry for the planetary transit
candidate star OGLE-TR-82. Good seeing V-band images acquired with VIMOS
instrument at ESO VLT allowed us to measure V=20.6+-0.03 mag star in spite of
the presence of a brighter neighbour about 1" away. This faint magnitude
answers the question why it has not been possible to measure radial velocities
for this object. One transit of this star has been observed with GMOS-S
instrument of GEMINI-South telescope in i and g-bands. The measurement of the
transit allows us to verify that this is not a false positive, to confirm the
transit amplitude measured by OGLE, and to improve the ephemeris. The transit
is well defined in i-band light curve, with a depth of A_i=0.034 mag. It is
however, less well defined, but deeper (A_g=0.1 mag) in the g-band, in which
the star is significantly fainter. The near-infrared photometry obtained with
SofI array at the ESO-NTT yields K=12.2+-0.1 and V-K=8.4+-0.1, so red that it
is unlike any other transit candidate studied before. Due to the extreme nature
of this object, we have not yet been able to measure velocities for this star,
but based on the new data we consider two different possible configurations:(1)
a nearby M7V star, or (2) a blend with a very reddened distant red giant. The
nearby M7V dwarf hypothesis would give a radius for the companion of
R_p=0.3+-0.1 R_J, i.e. the size of Neptune. Quantitative analysis of near-IR
spectroscopy finally shows that OGLE-TR-82 is a distant, reddened metal poor
early K giant. This result is confirmed by direct comparison with stellar
templates that gives the best match for a K3III star. Therefore, we discard the
planetary nature of the companion. Based on all the new data, we conclude that
this system is a main-sequence binary blended with a background red giant.


title: Coevolution of agents and networks in an epidemiological model

abstract:
  We study the spreading of an infection within an SIS epidemiological model on
a network. Susceptible agents are given the opportunity of breaking their links
with infected agents, and reconnecting those links with the rest of the
population. Thus, the network coevolves with the population as the infection
progresses. We show that a moderate reconnection frequency is enough to
completely suppress the infection. A partial, rather weak isolation of infected
agents suffices to eliminate the endemic state.


title: Unstable Disk Galaxies. I. Modal Properties

abstract:
  I utilize the Petrov-Galerkin formulation and develop a new method for
solving the unsteady collisionless Boltzmann equation in both the linear and
nonlinear regimes. In the first order approximation, the method reduces to a
linear eigenvalue problem which is solved using standard numerical methods. I
apply the method to the dynamics of a model stellar disk which is embedded in
the field of a soft-centered logarithmic potential. The outcome is the full
spectrum of eigenfrequencies and their conjugate normal modes for prescribed
azimuthal wavenumbers. The results show that the fundamental bar mode is
isolated in the frequency space while spiral modes belong to discrete families
that bifurcate from the continuous family of van Kampen modes. The population
of spiral modes in the bifurcating family increases by cooling the disk and
declines by increasing the fraction of dark to luminous matter. It is shown
that the variety of unstable modes is controlled by the shape of the dark
matter density profile.


title: Differential elliptic flow prediction at the LHC from parton transport

abstract:
  We predict how differential elliptic flow v2(pT) changes from RHIC to LHC
collision energies (Pb+Pb at 5.5 TeV/nucleon), ASSUMING that the quark-gluon
system created has a ``minimal'' shear viscosity eta/s = 1/(4*pi) at both RHIC
and the LHC.


title: On the Orbit Structure of the Logarithmic Potential

abstract:
  We investigate the dynamics in the logarithmic galactic potential with an
analytical approach. The phase-space structure of the real system is
approximated with resonant detuned normal forms constructed with the method
based on the Lie transform. Attention is focused on the properties of the axial
periodic orbits and of low order `boxlets' that play an important role in
galactic models. Using energy and ellipticity as parameters, we find analytical
expressions of several useful indicators, such as stability-instability
thresholds, bifurcations and phase-space fractions of some orbit families and
compare them with numerical results available in the literature.


title:
Self-Similar Solutions of Viscous-Resistive ADAFs With Poloidal Magnetic
  Fields

abstract:
  We carry out the self-similar solutions of viscous-resistive accretion flows
around a magnetized compact object. We consider an axisymmetric, rotating,
isotheral steady accretion flow which contains a poloidal magnetic field of the
central star. The dominant mechanism of energy dissipation is assumed to be the
turbulence viscosity and magnetic diffusivity due to magnetic field of the
central star. We explore the effect of viscosity on a rotating disk in the
presence of constant magnetic diffusivity. We show that the dynamical
quantities of ADAFs are sensitive to the advection and viscosity parameters.
Increase of the $\alpha$ coefficient in the $\alpha$-prescription model
decreases the radial velocity and increases the density of the flow. It also
affects the poloidal magnetic field considerably.


title:
Particle acceleration by fluctuating electric fields at a magnetic field
  null point

abstract:
  Particle acceleration consequences from fluctuating electric fields
superposed on an X-type magnetic field in collisionless solar plasma are
studied. Such a system is chosen to mimic generic features of dynamic
reconnection, or the reconnective dissipation of a linear disturbance. We
explore numerically the consequences for charged particle distributions of
fluctuating electric fields superposed on an X-type magnetic field. Particle
distributions are obtained by numerically integrating individual charged
particle orbits when a time varying electric field is superimposed on a static
X-type neutral point. This configuration represents the effects of the passage
of a generic MHD disturbance through such a system. Different frequencies of
the electric field are used, representing different possible types of wave. The
electric field reduces with increasing distance from the X-type neutral point
as in linear dynamic magnetic reconnection. The resulting particle
distributions have properties that depend on the amplitude and frequency of the
electric field. In many cases a bimodal form is found. Depending on the
timescale for variation of the electric field, electrons and ions may be
accelerated to different degrees and often have energy distributions of
different forms. Protons are accelerated to $\gamma$-ray producing energies and
electrons to and above hard X-ray producing energies in timescales of 1 second.
The acceleration mechanism is possibly important for solar flares and solar
noise storms but is also applicable to all collisionless plasmas.


title: Fine Tuning in Supersymmetric Models

abstract:
  The solution of a fine tuning problem is one of the principal motivations of
Supersymmetry. However experimental constraints indicate that many
Supersymmetric models are also fine tuned (although to a much lesser extent).
We review the traditional measure of this fine tuning used in the literature
and propose an alternative. We apply this to the MSSM and show the
implications.


title:
The geometry of the critical set of nonlinear periodic Sturm-Liouville
  operators

abstract:
  We study the critical set C of the nonlinear differential operator F(u) = -u"
+ f(u) defined on a Sobolev space of periodic functions H^p(S^1), p >= 1. Let
R^2_{xy} \subset R^3 be the plane z = 0 and, for n > 0, let cone_n be the cone
x^2 + y^2 = tan^2 z, |z - 2 pi n| < pi/2; also set Sigma = R^2_{xy} U U_{n > 0}
cone_n. For a generic smooth nonlinearity f: R -> R with surjective derivative,
we show that there is a diffeomorphism between the pairs (H^p(S^1), C) and
(R^3, Sigma) x H where H is a real separable infinite dimensional Hilbert
space.


title:
On the solution of trivalent decision problems by quantum state
  identification

abstract:
  The trivalent functions of a trit can be grouped into equipartitions of three
elements. We discuss the separation of the corresponding functional classes by
quantum state identifications.


title: Multi-Particle Decays of Light Mesons Measured by PHENIX at RHIC

abstract:
  The PHENIX experiment at RHIC measured K0S, eta and omega-meson production at
high pT in p+p, d+Au and Au+Au collisions at sqrt(s_NN)=200 GeV. Measurements
performed in different hadronic decay channels give consistent results. This
paper presents measured meson-to-pi0 ratios and Nuclear Modification factors in
the most central d+Au and Au+Au collisions. No suppression seen in d+Au
interactions is in contrast to a strong suppression of meson yields revealed in
central Au+Au collisions at the same energy.


title: Spin Physics: Session Summary

abstract:
  We summarize the main results of the spin physics Working Group Session of
DIS 2007, the 15th International Workshop on ``Deep-Inelastic Scattering and
Related Subjects''.


title:
An efficient quantum algorithm for the hidden subgroup problem in nil-2
  groups

abstract:
  In this paper we extend the algorithm for extraspecial groups in
\cite{iss07}, and show that the hidden subgroup problem in nil-2 groups, that
is in groups of nilpotency class at most 2, can be solved efficiently by a
quantum procedure. The algorithm presented here has several additional
features. It contains a powerful classical reduction for the hidden subgroup
problem in nilpotent groups of constant nilpotency class to the specific case
where the group is a $p$-group of exponent $p$ and the subgroup is either
trivial or cyclic. This reduction might also be useful for dealing with groups
of higher nilpotency class. The quantum part of the algorithm uses well chosen
group actions based on some automorphisms of nil-2 groups. The right choice of
the actions requires the solution of a system of quadratic and linear
equations. The existence of a solution is guaranteed by the Chevalley-Warning
theorem, and we prove that it can also be found efficiently.


title: Search for Low Mass Exotic leptonic or bosonic structures

abstract:
  Recently, several papers discussed the existence of a low mass leptonic
structure. It was suggested that the $\Sigma^{+}$ disintegration:
$\Sigma^{+}\to$pP$^{0}$, P$^{0}\to\mu^{-}\mu^{+}$ proceeds through an
intermediate particle P$^{0}$ having a mass close to M$\approx$~214.3 MeV. The
present work intends to look at other available data, in order to observe the
eventual existence of a small peak or shoulder, at a mass close to M=214.3 MeV,
which can strengthen the existence of a state produced by two leptons of
opposite electric charge.


title:
The Different Physical Mechanisms that Drive the Star-Formation
  Histories of Giant and Dwarf Galaxies

abstract:
  We present an analysis of star-formation and nuclear activity in galaxies as
a function of both luminosity and environment in the SDSS DR4 dataset. Using a
sample of 27753 galaxies at 0.005<z<0.037 that is >90% complete to Mr=-18.0 we
find that the EW(Ha) distribution is strongly bimodal, allowing galaxies to be
robustly separated into passive and star-forming populations about a value
EW(Ha)=2A. In high-density regions ~70% of galaxies are passive independent of
luminosity. In the rarefied field however, the fraction of passively-evolving
galaxies is a strong function of luminosity, dropping from ~50% for Mr<-21 to
zero by Mr~-18. Indeed for the lowest luminosity range covered (-18<Mr<-16)
none of the ~600 galaxies in the lowest density quartile are passive. The few
passively-evolving dwarf galaxies in field regions appear as satellites to
bright (~L*) galaxies. The fraction of galaxies with optical AGN signatures
decreases steadily from ~50% at Mr~-21 to ~0% by Mr~-18 closely mirroring the
luminosity-dependence of the passive galaxy fraction in low-density
environments. This result reflects the increasing importance of AGN feedback
with galaxy mass for their evolution, such that the star-formation histories of
massive galaxies are primarily determined by their past merger history. In
contrast, the complete absence of passively-evolving dwarf galaxies more than
~2 virial radii from the nearest massive halo (i.e. cluster, group or massive
galaxy) indicates that internal processes, such as merging, AGN feedback or gas
consumption through star-formation, are not responsible for terminating
star-formation in dwarf galaxies. Instead the evolution of dwarf galaxies is
primarily driven by the mass of their host halo, probably through the combined
effects of tidal forces and ram-pressure stripping.


title: Affine systems: asymptotics at infinity for fractal measures

abstract:
  We study measures on $\mathbb{R}^d$ which are induced by a class of infinite
and recursive iterations in symbolic dynamics. Beginning with a finite set of
data, we analyze prescribed recursive iteration systems, each involving
subdivisions. The construction includes measures arising from affine and
contractive iterated function systems with and without overlap (IFSs), i.e.,
limit measures $\mu$ induced by a finite family of affine mappings in
$\mathbb{R}^d$ (the focus of our paper), as well as equilibrium measures in
complex dynamics.
  By a systematic analysis of the Fourier transform of the measure $\mu$ at
hand (frequency domain), we identify asymptotic laws, spectral types,
dichotomy, and chaos laws. In particular we show that the cases when $\mu$ is
singular carry a gradation, ranging from Cantor-like fractal measures to
measures exhibiting chaos, i.e., a situation when small changes in the initial
data produce large fluctuations in the outcome, or rather, the iteration limit
(in this case the measures). Our method depends on asymptotic estimates on the
Fourier transform of $\mu$ for paths at infinity in $\mathbb{R}^d$. We show how
properties of $\mu$ depend on perturbations of the initial data, e.g.,
variations in a prescribed finite set of affine mappings in $\mathbb{R}^d$, in
parameters of a rational function in one complex variable (Julia sets and
equilibrium measures), or in the entries of a given infinite positive definite
matrix.


title:
Intrinsic optical bistability of thin films of linear molecular
  aggregates: The one-exciton approximation

abstract:
  We perform a theoretical study of the nonlinear optical response of an
ultrathin film consisting of oriented linear aggregates. A single aggregate is
described by a Frenkel exciton Hamiltonian with uncorrelated on-site disorder.
The exciton wave functions and energies are found exactly by numerically
diagonalizing the Hamiltonian. The principal restriction we impose is that only
the optical transitions between the ground state and optically dominant states
of the one-exciton manifold are considered, whereas transitions to other
states, including those of higher exciton manifolds, are neglected. The optical
dynamics of the system is treated within the framework of truncated optical
Maxwell-Bloch equations in which the electric polarization is calculated by
using a joint distribution of the transition frequency and the transition
dipole moment of the optically dominant states. This function contains all the
statistical information about these two quantities that govern the optical
response, and is obtained numerically by sampling many disorder realizations.
We derive a steady-state equation that establishes a relationship between the
output and input intensities of the electric field and show that within a
certain range of the parameter space this equation exhibits a three-valued
solution for the output field. A time-domain analysis is employed to
investigate the stability of different branches of the three-valued solutions
and to get insight into switching times. We discuss the possibility to
experimentally verify the bistable behavior.


title: Coarse grained models in Coulomb-frustrated phase separation

abstract:
  Competition between interactions on different length scales leads to
self-organized textures in classical as well as quantum systems. This pattern
formation phenomenon has been invoked to explain some intriguing properties of
a large variety of strongly correlated electronic systems that includes for
example high temperature superconductors and colossal magnetoresistance
manganites. We classify the more common situations in which Coulomb frustrated
phase separation can occur and review their properties.


title: Building Decision Procedures in the Calculus of Inductive Constructions

abstract:
  It is commonly agreed that the success of future proof assistants will rely
on their ability to incorporate computations within deduction in order to mimic
the mathematician when replacing the proof of a proposition P by the proof of
an equivalent proposition P' obtained from P thanks to possibly complex
calculations. In this paper, we investigate a new version of the calculus of
inductive constructions which incorporates arbitrary decision procedures into
deduction via the conversion rule of the calculus. The novelty of the problem
in the context of the calculus of inductive constructions lies in the fact that
the computation mechanism varies along proof-checking: goals are sent to the
decision procedure together with the set of user hypotheses available from the
current context. Our main result shows that this extension of the calculus of
constructions does not compromise its main properties: confluence, subject
reduction, strong normalization and consistency are all preserved.


title:
Production of multipartite entanglement for electron spins in quantum
  dots

abstract:
  We propose how to generate genuine multipartite entanglement of electron spin
qubits in a chain of quantum dots using the naturally available single-qubit
rotations and two-qubit Heisenberg exchange interaction in the system. We show
that the minimum number of required operations to generate entangled states of
the GHZ-, cluster and W-type scales linearly with the number of qubits and
estimate the fidelities of the generated entangled cluster states. As the
required single and two-qubit operations have recently been realized, our
proposed scheme opens the way for experimental investigation of multipartite
entanglement with electron spin qubits.


title: Direct CP violation of $B \to l \nu$ in unparticle physics

abstract:
  We have investigated the effects of unparticles in decays $B \to l \nu$. It
is found that the direct CP violation in the decays, which is zero in SM, can
show up due to the CP conserving phase intrinsic in unparticle physics. For
$l=\tau$, the direct CP asymmetry can reach 30% for the scalar unparticle
contribution, and 100% for the longitudinal vector unparticle contribution
under the constraints of ${\rm Br}(B\to\tau\nu)$ and $\nu e$ elastic
scattering. If both unparticle-lepton coupling universality and
unparticle-quark coupling universality are assumed the constraint from
$Br(\pi\to \mu\nu)$ leads that the direct CP violation in $B\to l\nu$ can only
reach at most 8% and 1% for scalar and vector unparticle contributions
respectively if $d_{\cal U} < 2$. If the direct CP violation is observed in the
future it would give strong evidence for the existence of unparticle stuff.


title: Quarkonium Spectroscopy: Beyond One-Gluon Exchange

abstract:
  In this work an improved potential model for quarkonium spectra (charmonium,
bottomonium) is constructed. Beside the one-gluon exchange and a linear
confinement potential, the model includes systematically effects from two-gluon
exchange and the induced interaction (i.e. t-channel exchanges of
quark-antiquark bound states). These turn out to be important in order to
reproduce correctly the fine- and hyperfine structure of the charmonium and
bottomonium states. It is demonstrated that such a satisfactory description of
the quarkonium spectra can be obtained with parameters (quark masses, strong
coupling constant and string tension) consistent with values of lattice
simulations and QCD determinations.


title:
Spherically symmetric selfdual Yang-Mills instantons on curved
  backgrounds in all even dimensions

abstract:
  We present several different classes of selfdual Yang-Mills instantons in all
even d backgrounds with Euclidean signature. In d=4p+2 the only solutions we
found are on constant curvature dS and AdS backgrounds, and are evaluated in
closed form. In d=4p an interesting class of instantons are given on black hole
backgrounds. One class of solutions are (Euclidean) time-independent and
spherically symmetric in d-1 dimensions, and the other class are spherically
symmetric in all d dimensions. Some of the solutions in the former class are
evaluated numerically, all the rest being given in closed form. Analytic proofs
of existence covering all numerically evaluated solutions are given. All
instantons studied have finite action and vanishing energy momentum tensor and
do not disturb the geometry.


title:
Sine-Gordon description of Beresinskii-Kosterlitz-Thouless physics at
  finite magnetic field

abstract:
  The Beresinskii-Kosterlitz-Thouless (BKT) physics of vortices in
two-dimensional superconductors at finite magnetic field is investigated by
means of a field-theoretical approach based on the sine-Gordon model. This
description leads to a straightforward definition of the field-induced
magnetization and shows that the persistence of non-linear effects at low
fields above the transition is a typical signature of the fast divergence of
the correlation length within the BKT theory.


title: Remarks on the amplitude of the decay Upsilon(3S) -> Upsilon(1S) pi pi

abstract:
  We point out some properties of the amplitude of the dipion transition
$\Upsilon(3S) \to \Upsilon(1S) \pi \pi$ in relation to the recently reported
results of a CLEO analysis of form factors in this amplitude. We find that the
reported significant complex phase between two of the form factors under the
assumption that the third form factor is zero, is not consistent with the
picture where the phase shifts arise due to the final state interaction in the
$\pi \pi$ channel. It is also shown that in an analysis that uses no
information on the polarization of both the initial and the final $\Upsilon$
resonances it is impossible in principle to determine all the relevant terms.
We suggest that a study of a simple correlation between the direction of the
total momentum of the two pions and the axis of the initial beams is sufficient
to resolve the ambiguity in the fit for the form factors.


title: Exotic Searches at the Tevatron

abstract:
  Recent results on searches for new physics at Run II of the Tevatron are
reported. The searches cover many different final states and previous hints of
signals, but all analyses have at this point led to negative results.


title:
Some intersection numbers of divisors on toroidal compactifications of
  A_g

abstract:
  We study the top intersection numbers of the boundary and Hodge class
divisors on toroidal compactifications of the moduli space $A_g$ of principally
polarized abelian varieties and compute those numbers that live away from the
stratum which lies over the closure of $A_{g-3}$ in the Satake
compactification.


title: Radiative return physics program within EURIDICE network

abstract:
  A short review of both theoretical and experimental aspects of the radiative
return method is presented with the emphasize on the results obtained within
the EURIDICE network. It is shown that the method gives not only possibility of
an independent from the scan method measurement of the hadronic cross section,
but also can provide information concerning details of the hadronic
interactions.


title:
Quantitative implications of the secondary role of carbon dioxide
  climate forcing in the past glacial-interglacial cycles for the likely future
  climatic impacts of anthropogenic greenhouse-gas forcings

abstract:
  A review of the recent refereed literature fails to confirm quantitatively
that carbon dioxide (CO2) radiative forcing was the prime mover in the changes
in temperature, ice-sheet volume, and related climatic variables in the glacial
and interglacial periods of the past 650,000 years, even under the "fast
response" framework where the convenient if artificial distinction between
forcing and feedback is assumed. Atmospheric CO2 variations generally follow
changes in temperature and other climatic variables rather than preceding them.
Likewise, there is no confirmation of the often-posited significant supporting
role of methane (CH4) forcing, which despite its faster atmospheric response
time is simply too small, amounting to less than 0.2 W/m2 from a change of 400
ppb. We cannot quantitatively validate the numerous qualitative suggestions
that the CO2 and CH4 forcings that occurred in response to the Milankovich
orbital cycles accounted for more than half of the amplitude of the changes in
the glacial/interglacial cycles of global temperature, sea level, and ice
volume. Consequently, we infer that natural climatic variability notably the
persistence of insolation forcing at key seasons and geographical locations,
taken with closely-related thermal, hydrological, and cryospheric changes (such
as the water vapor, cloud, and ice-albedo feedbacks) suffices in se to explain
the proxy-derived, global and regional, climatic and environmental
phase-transitions in the paleoclimate. If so, it may be appropriate to place
anthropogenic greenhouse-gas emissions in context by separating their
medium-term climatic impacts from those of a host of natural forcings and
feedbacks that may, as in paleoclimatological times, prove just as significant.


title: Infall and accretion

abstract:
  Gas infall and accretion play a fundamental role in galaxy formation, and
several processes of accretion are reviewed. In particular the cold accretion
may solve to some extent the angular momentum problem in disk formation, while
it is aggravated by mergers. Gas accretion is one of the main actor in secular
evolution: it is required to account for recurrent bar formation, and to
explain the feedback cycles of formation of bulges and black holes, with
correlated masses. Infall is also required to fuel a regular and almost
stationary star formation history. Star formation is quenched for galaxy in
clusters when gas accretion is suppressed through stripping. The central
brighter central galaxy can benefit however of gas accretion through cooling
flows, moderated by AGN feedback. Hot and cold feedback scenarios can be
considered, to account for a stationary cooling flow, and explain the
filamentary CO and Halpha observed structures.


title:
Inducement and suppression of Coulomb effects in elastic 2D-2D electron
  tunnelling in a quantizing magnetic field

abstract:
  Tunnelling between two-dimensional electron systems has been studied in the
magnetic field perpendicular to the systems planes. The satellite conductance
peaks of the main resonance have been observed due to the electron tunnelling
assisted by the elastic scattering on impurities in the barrier layer. These
peaks are shown to shift to the higher voltage due to the Coulomb pseudogap in
the intermediate fields. In the high magnetic fields the pseudogap shift is
disappeared.


title: Toward Understanding Massive Star Formation

abstract:
  Although fundamental for astrophysics, the processes that produce massive
stars are not well understood. Large distances, high extinction, and short
timescales of critical evolutionary phases make observations of these processes
challenging. Lacking good observational guidance, theoretical models have
remained controversial. This review offers a basic description of the collapse
of a massive molecular core and a critical discussion of the three competing
concepts of massive star formation:
  - monolithic collapse in isolated cores
  - competitive accretion in a protocluster environment
  - stellar collisions and mergers in very dense systems
  We also review the observed outflows, multiplicity, and clustering properties
of massive stars, the upper initial mass function and the upper mass limit. We
conclude that high-mass star formation is not merely a scaled-up version of
low-mass star formation with higher accretion rates, but partly a mechanism of
its own, primarily owing to the role of stellar mass and radiation pressure in
controlling the dynamics.


title: Dynamics of Exozodiacal Clouds

abstract:
  The inner Solar System contains a cloud of small (1-100 micron) dust grains
created when small bodies-asteroids, comets, and Kuiper belt objects-collide
and outgas. This dust cloud, the zodiacal cloud probably has extrasolar
analogs, exozodiacal clouds. Exozodiacal clouds are related to debris disks,
clouds of rocks and dust orbiting main sequence stars thought to represent the
debris left over from planet formation. Some debris disks appear to contain
distinct inner clouds that could be considered massive exozodiacal clouds (e.g.
Koerner et al. 1998, Absil et al. 2006). This white paper addresses the need
for future theoretical work on the dynamics of exozodiacal clouds. This
theoretical work should help us discover new planets and understand exozodiacal
clouds as astrophysical noise. So far, observations of nearby stars have not
provided good constraints on the structures of exozodiacal clouds. But future
observations probably will demand a better theoretical understanding of these
systems.


title: Knotted Polyhedral Tori

abstract:
  For every knot K with stick number k there is a knotted polyhedral torus of
knot type K with 3k vertices. We prove that at least 3k-2 vertices are
necessary.


title: Statistical Model Predictions for p-p and Pb-Pb collisions at LHC

abstract:
  Predictions for particle production at LHC are discussed in the context of
the statistical model. Moreover, the capability of particle ratios to determine
the freeze-out point experimentally is studied, and the best suited ratios are
specified. Finally, canonical suppression in p-p collisions at LHC energies is
discussed in a cluster framework. Measurements with p-p collisions will allow
us to estimate the strangeness correlation volume and to study its evolution
over a large range of incident energies.


title: Antikaons and hyperons in nuclear matter with saturation

abstract:
  We evaluate the antikaon and hyperon spectral functions in a self-consistent
and covariant many-body approach. The computation is based on coupled-channel
dynamics derived from the chiral SU(3) Lagrangian. A novel subtraction scheme
is developed that avoids kinematical singularities and medium-induced power
divergencies all together. Scalar and vector mean fields are used to model
nuclear binding and saturation. The effect of the latter is striking for the
antikaon spectral function that becomes significantly more narrow at small
momenta. Attractive mass shifts of about 30 and 40 MeV are predicted for the
Lambda(1405) and Sigma(1385) resonances. Once scalar and vector mean fields for
the nucleon are switched on the Lambda(1520) resonances dissolves almost
completely in nuclear matter. All together only moderate attraction is
predicted for the nuclear antikaon systems at saturation density. However, at
larger densities we predict a sizable population of soft antikaon modes that
arise from the coupling of the antikaon to a highly collective Lambda(1115)
nucleon-hole state. This may lead to the formation of exotic nuclear systems
with strangeness and antikaon condensation in compact stars at moderate
densities.


title: Magnetic strings in Lattice QCD as Nonabelian Vortices

abstract:
  Lattice studies indicate existence of magnetic strings in QCD vacuum. We
argue that recently found nonabelian strings with rich worldsheet dynamics
provide a proper pattern for the strings observed on the lattice. In
particular, within this pattern we explain the localization of the
monopole-antimonopole pairs on the magnetic string worldsheet and the negative
contribution of the magnetic strings into the vacuum energy and gluon
condensate. We suggest the D2 brane realization of the magnetic string which
explains the temperature dependence of its tension.


title: Second-order QCD corrections to the thrust distribution

abstract:
  We compute the next-to-next-to-leading order (NNLO) QCD corrections to the
thrust distribution in electron-positron annihilation. The corrections turn out
to be sizable, enhancing the previously known next-to-leading order prediction
by about 15%. Inclusion of the NNLO corrections significantly reduces the
theoretical renormalisation scale uncertainty on the prediction of the thrust
distribution.


title: Light 1-+ exotics: molecular resonances

abstract:
  Highlights in the search for nonconventional (non qqbar) meson states are the
pi_1(1400) and pi_1(1600) exotic candidates. Should they exist, mounting
theoretical arguments suggest that they are tetraquark molecular resonances
excitable by meson rescattering.
  We report a new tetraquark calculation within a model field theory
approximation to Quantum Chromodynamics in the Coulomb gauge supporting this
conjecture. We also strengthen this claim by consistently contrasting results
with exotic state predictions for hybrid (q qbar g) mesons within the same
theoretical framework.
  Our findings confirm that molecular-like configurations involving two color
singlets (a resonance, not a bound state) are clearly favored over hybrid or
color-exotic tetraquark meson (q qbar q qbar atoms) formation.
  Finally, to assist needed further experimental searches we document a useful
off-plane correlator for establishing the structure of these exotic systems
along with similar, but anticipated much narrower, states that should exist in
the charmonium and bottomonium spectra.


title: Monge-Ampere equations and moduli spaces of manifolds of circular type

abstract:
  A (bounded) manifold of circular type is a complex manifold M of dimension n
admitting a (bounded) exhaustive real function u, defined on M minus a point
x_o, so that: a) it is a smooth solution on $M\setminus {x_o}$ to the
Monge-Amp\`ere equation $(d d^c u)^n = 0$; b) x_o is a singular point for u of
logarithmic type and e^u extends smoothly on the blow up of M at x_o; c) $d d^c
(e^u) >0$ at any point of $M\setminus {x_o}$. This class of manifolds naturally
includes all smoothly bounded, strictly linearly convex domains and all
smoothly bounded, strongly pseudoconvex circular domains of $\bC^n$. The moduli
spaces of bounded manifolds of circular type are studied. In particular, for
each biholomorphic equivalence class of them it is proved the existence of an
essentially unique manifold in normal form. It is also shown that the class of
normalizing maps for an n-dimensional manifold M is a new holomorphic invariant
with the following property: it is parameterized by the points of a finite
dimensional real manifold of dimension n^2 when M is a (non-convex) circular
domain while it is of dimension $n^2 + 2 n$ when M is a strictly convex domain.
New characterizations of the circular domains and of the unit ball are also
obtained.


title:
Espaces de repr\'esentation multidimensionnels d\'edi\'es \`a la
  visualisation

abstract:
  In decision-support systems, the visual component is important for On Line
Analysis Processing (OLAP). In this paper, we propose a new approach that faces
the visualization problem due to data sparsity. We use the results of a
Multiple Correspondence Analysis (MCA) to reduce the negative effect of
sparsity by organizing differently data cube cells. Our approach does not
reduce sparsity, however it tries to build relevant representation spaces where
facts are efficiently gathered. In order to evaluate our approach, we propose
an homogeneity criterion based on geometric neighborhood of cells. The obtained
experimental results have shown the efficiency of our method.


title: Conformal quaternionic contact curvature and the local sphere theorem

abstract:
  A tensor invariant is defined on a quaternionic contact manifold in terms of
the curvature and torsion of the Biquard connection involving derivatives up to
third order of the contact form. This tensor, called quaternionic contact
conformal curvature, is similar to the Weyl conformal curvature in Riemannian
geometry and to the Chern-Moser tensor in CR geometry. It is shown that a
quaternionic contact manifold is locally quaternionic contact conformal to the
standard flat quaternionic contact structure on the quaternionic Heisenberg
group, or equivalently, to the standard 3-sasakian structure on the sphere iff
the quaternionic contact conformal curvature vanishes.


title: Smoothness Theorem for Differential BV Algebras

abstract:
  Associated to a differential BV algebra are two differential graded Lie
algebras: we call one classical and the other, which contains a formal h-bar
parameter, quantum. The classical dgLa is always smooth formal. In this paper,
we give necessary and sufficient conditions for the quantum dgLa to be smooth
formal. These conditions are equivalent to the degeneration of a version of the
noncommutative Hodge to de Rham spectral sequence. References added.


title: Implications of the Crystal Barrel data for meson-baryon symmetries

abstract:
  Making use of numerous resonances discovered by the Crystal Barrel
Collaboration we discuss some possible relations between the baryon and meson
spectra of resonances composed of the light non-strange quarks. Our goal is to
indicate new features that should be reproduced by the realistic dynamical
models describing the hadron spectrum in the sector of light quarks.


title: Poisson transform for higher-rank graph algebras and its applications

abstract:
  Higher-rank graph generalisations of the Popescu-Poisson transform are
constructed, allowing us to develop a dilation theory for higher rank operator
tuples. These dilations are joint dilations of the families of operators
satisfying relations encoded by the graph structure which we call
$\Lambda$-contractions or $\Lambda$-coisometries. Besides commutant lifting
results and characterisations of pure states on higher rank graph algebras
several applications to the structure theory of non-selfadjoint graph operator
algebras are presented generalising recent results in special cases.


title: Circumbinary Molecular Rings Around Young Stars in Orion

abstract:
  We present high angular resolution 1.3 mm continuum, methyl cyanide molecular
line, and 7 mm continuum observations made with the Submillimeter Array and the
Very Large Array, toward the most highly obscured and southern part of the
massive star forming region OMC1S located behind the Orion Nebula. We find two
flattened and rotating molecular structures with sizes of a few hundred
astronomical units suggestive of circumbinary molecular rings produced by the
presence of two stars with very compact circumstellar disks with sizes and
separations of about 50 AU, associated with the young stellar objects 139-409
and 134-411. Furthermore, these two circumbinary rotating rings are related to
two compact and bright {\it hot molecular cores}. The dynamic mass of the
binary systems obtained from our data are $\geq$ 4 M$_\odot$ for 139-409 and
$\geq$ 0.5 M$_\odot$ for 134-411. This result supports the idea that
intermediate-mass stars will form through {\it circumstellar disks} and
jets/outflows, as the low mass stars do. Furthermore, when intermediate-mass
stars are in multiple systems they seem to form a circumbinary ring similar to
those seen in young, multiple low-mass systems (e.g., GG Tau and UY Aur).


title: Factorization Approaches to B Meson Decays

abstract:
  We compare the theoretical frameworks and the phenomenological applications
of the factorization approaches to exclusive $B$ meson decays, which include
QCD-improved factorization, perturbative QCD, and soft-collinear effective
theory. Recent progress on two-body nonleptonic $B$ meson decays made in these
approaches are reviewed.


title: Efficient supervised learning in networks with binary synapses

abstract:
  Recent experimental studies indicate that synaptic changes induced by
neuronal activity are discrete jumps between a small number of stable states.
Learning in systems with discrete synapses is known to be a computationally
hard problem. Here, we study a neurobiologically plausible on-line learning
algorithm that derives from Belief Propagation algorithms. We show that it
performs remarkably well in a model neuron with binary synapses, and a finite
number of `hidden' states per synapse, that has to learn a random
classification task. Such system is able to learn a number of associations
close to the theoretical limit, in time which is sublinear in system size. This
is to our knowledge the first on-line algorithm that is able to achieve
efficiently a finite number of patterns learned per binary synapse.
Furthermore, we show that performance is optimal for a finite number of hidden
states which becomes very small for sparse coding. The algorithm is similar to
the standard `perceptron' learning algorithm, with an additional rule for
synaptic transitions which occur only if a currently presented pattern is
`barely correct'. In this case, the synaptic changes are meta-plastic only
(change in hidden states and not in actual synaptic state), stabilizing the
synapse in its current state. Finally, we show that a system with two visible
states and K hidden states is much more robust to noise than a system with K
visible states. We suggest this rule is sufficiently simple to be easily
implemented by neurobiological systems or in hardware.

categories: q-bio.NC cond-mat.stat-mech cs.NE q-bio.QM


title:
No light shining through a wall : new results from a photoregeneration
  experiment

abstract:
  Recently, axion-like particle search has received renewed interest. In
particular, several groups have started ``light shining through a wall''
experiments based on magnetic field and laser both continuous, which is very
demanding in terms of detector background. We present here the 2$\sigma$ limits
obtained so far with our novel set-up consisting of a pulsed magnetic field and
a pulsed laser. In particular, we have found that the axion-like particle two
photons inverse coupling constant $M$ is $> 8\times 10^5$ GeV provided that the
particle mass $m_\mathrm{a} \sim$ 1 meV. Our results definitively invalidate
the axion interpretation of the original PVLAS optical measurements with a
confidence level greater than 99.9%.


title:
Hubble Diagram of Gamma-Rays Bursts calibrated with Gurzadyan-Xue
  Cosmology

abstract:
  Gamma-ray bursts (GRBs) being the most luminous among known cosmic objects
carry an essential potential for cosmological studies if properly used as
standard candles. In this paper we test with GRBs the cosmological predictions
of the Gurzadyan-Xue (GX) model of dark energy, a novel theory that predicts,
without any free parameters, the current vacuum fluctuation energy density
close to the value inferred from the SNIa observations. We also compare the GX
results with those predicted by the concordance scenario $\Lambda$-CDM.
According to the statistical approach by Schaefer (2007), the use of several
empirical relations obtained from GRBs observables, after a consistent
calibration for a specific model, enables one to probe current cosmological
models. Based on this recently introduced method, we use the 69 GRBs sample
collected by Schaefer (2007); and the most recently released SWIFT satellite
data (Sakamoto et al. 2007) together with the 41 GRBs sample collected by
Rizzuto et al. (2007), which has the more firmly determined redshifts. Both
data samples span a distance scale up to redshift about 7. We show that the GX
models are compatible with the Hubble diagram of the Schaefer (2007) 69 GRBs
sample. Such adjustment is almost identical to the one for the concordance
$\Lambda$-CDM.


title: Cosmic kinematic dynamos in non-singular anisotropic universe

abstract:
  A marginally excited cosmic kinematic dynamo is found in the background of a
non-singular anisotropic Kasner cosmological metric solution of Einstein field
equation of general relativity. The magnetic field is not amplified but is
frozen inside the universe. Since a finite resistivity is assumed, a
nonsingular flow velocity is orthogonal to the magnetic field plane. The model
presents an inflationary phase. Magnetic field components are stretched along
the orthogonal planar directions while the flow is orthogonal to this magnetic
sheet. The self-induction magnetohydrodynamic field equation in Kasner universe
may be written in the form of a polynomial in the time coordinate which yields
a periodic flow.


title:
Singular forces and point-like colloids in lattice Boltzmann
  hydrodynamics

abstract:
  We present a second-order accurate method to include arbitrary distributions
of force densities in the lattice Boltzmann formulation of hydrodynamics. Our
method may be used to represent singular force densities arising either from
momentum-conserving internal forces or from external forces which do not
conserve momentum. We validate our method with several examples involving point
forces and find excellent agreement with analytical results. A minimal model
for dilute sedimenting particles is presented using the method which promises a
substantial gain in computational efficiency.


title: Analytic results on the geometric entropy for free fields

abstract:
  The trace of integer powers of the local density matrix corresponding to the
vacuum state reduced to a region V can be formally expressed in terms of a
functional integral on a manifold with conical singularities. Recently, some
progress has been made in explicitly evaluating this type of integrals for free
fields. However, finding the associated geometric entropy remained in general a
difficult task involving an analytic continuation in the conical angle. In this
paper, we obtain this analytic continuation explicitly exploiting a relation
between the functional integral formulas and the Chung-Peschel expressions for
the density matrix in terms of correlators. The result is that the entropy is
given in terms of a functional integral in flat Euclidean space with a cut on V
where a specific boundary condition is imposed. As an example we get the exact
entanglement entropies for massive scalar and Dirac free fields in 1+1
dimensions in terms of the solutions of a non linear differential equation of
the Painleve V type.


title:
Static Screening and Delocalization Effects in the Hubbard-Anderson
  Model

abstract:
  We study the suppression of electron localization due to the screening of
disorder in a Hubbard-Anderson model. We focus on the change of the electron
localization length at the Fermi level within a static picture, where
interactions are absorbed into the redefinition of the random on-site energies.
Two different approximations are presented, either one yielding a nonmonotonic
dependence of the localization length on the interaction strength, with a
pronounced maximum at an intermediate interaction strength. In spite of its
simplicity, our approach is in good agreement with recent numerical results.


title:
Superfluidity of fermions with repulsive on-site interaction in an
  anisotropic optical lattice near a Feshbach resonance

abstract:
  We present a numerical study on ground state properties of a one-dimensional
(1D) general Hubbard model (GHM) with particle-assisted tunnelling rates and
repulsive on-site interaction (positive-U), which describes fermionic atoms in
an anisotropic optical lattice near a wide Feshbach resonance. For our
calculation, we utilize the time evolving block decimation (TEBD) algorithm,
which is an extension of the density matrix renormalization group and provides
a well-controlled method for 1D systems. We show that the positive-U GHM, when
hole-doped from half-filling, exhibits a phase with coexistence of
quasi-long-range superfluid and charge-density-wave orders. This feature is
different from the property of the conventional Hubbard model with positive-U,
indicating the particle-assisted tunnelling mechanism in GHM brings in
qualitatively new physics.


title:
Variations in 24 micron morphologies among galaxies in the Spitzer
  Infrared Nearby Galaxies Survey: New insights into the Hubble sequence

abstract:
  To study the distribution of star formation and dust emission within nearby
galaxies, we measured five morphological parameters in the 3.6 and 24 micron
wave bands for 65 galaxies in the Spitzer Infrared Nearby Galaxies Survey
(SINGS) and 8 galaxies that were serendipitously observed by SINGS. The
morphological parameters demonstrate strong variations along the Hubble
sequence, including statistically significant differences between S0/a-Sab and
Sc-Sd galaxies. Early-type galaxies are generally found to be compact,
centralized, symmetric sources in the 24 micron band, while late-type galaxies
are generally found to be extended, asymmetric sources. These results suggest
that the processes that increase the real or apparent sizes of galaxies' bulges
also lead to more centralized 24 micron dust emission. Several phenomena, such
as strong nuclear star formation, Seyfert activity, or outer ring structures,
may cause galaxies to deviate from the general morphological trends observed at
24 microns. We also note that the 24 micron morphologies of Sdm-Im galaxies are
quite varied, with some objects appearing very compact and symmetric while
others appear diffuse and asymmetric. These variations reflect the wide
variation in star formation in irregular galaxies as observed at other
wavelengths. The variations in the 24 micron morphological parameters across
the Hubble sequence mirror many of the morphological trends seen in other
tracers of the ISM and in stellar emission. However, the 24 micron
morphological parameters for the galaxies in this sample do not match the
morphological parameters measured in the stellar wave bands. This implies that
the distribution of dust emission is related to but not equivalent to the
distribution of stellar emission.


title: Un index de jointure pour les entrep\^ots de donn\'ees XML

abstract:
  XML data warehouses form an interesting basis for decision-support
applications that exploit heterogeneous data from multiple sources. However,
XML-native database systems currently bear limited performances and it is
necessary to research ways to optimize them. In this paper, we propose a new
index that is specifically adapted to the multidimensional architecture of XML
warehouses and eliminates join operations, while preserving the information
contained in the original warehouse. A theoretical study and experimental
results demonstrate the efficiency of our index, even when queries are complex.


title: Correlation in single-photon experiments

abstract:
  Correlations of detection events in photodetectors placed at the opposite
sides of a beam splitter are studied in the frame of classical probability
theory. It is assumed that there is always one photon present during one
elementary measurement (one measurement act). Due to the conservation of
energy, thereis a strict anticorrelation in detections in one elementary
experiment, because the photon cannot excite both of the detectors at the same
time. It is explicitely shown in several examples that the bunching or
anti-bunching of the counts in serieses of elementary single-photon experiments
are governed by the statistical properties of grouping the sequences of the
elementary measurements.


title: S\'election simultan\'ee d'index et de vues mat\'erialis\'ees

abstract:
  Indices and materialized views are physical structures that accelerate data
access in data warehouses. However, these data structures generate some
maintenance overhead. They also share the same storage space. The existing
studies about index and materialized view selection consider these structures
separately. In this paper, we adopt the opposite stance and couple index and
materialized view selection to take into account the interactions between them
and achieve an efficient storage space sharing. We develop cost models that
evaluate the respective benefit of indexing and view materialization. These
cost models are then exploited by a greedy algorithm to select a relevant
configuration of indices and materialized views. Experimental results show that
our strategy performs better than the independent selection of indices and
materialized views.


title:
Bistability of the lac operon during growth of Escherichia coli on
  lactose and lactose + glucose

abstract:
  The lac operon of Escherichia coli exhibits bistability. Early studies showed
that bistability occurs during growth on TMG/succinate and lactose + glucose,
but not during growth on lactose. More recent studies with lacGFP-transfected
cells show bistability with TMG/succinate, but not with lactose and lactose +
glucose. In the literature, these results are attributed to variations of the
positive feedback generated by induction. Specifically, during growth on
TMG/succinate, induction generates positive feedback because the permease
stimulates the accumulation of TMG, which, in turn, promotes the synthesis of
more permease. This positive feedback is attenuated during growth on lactose
because hydrolysis of lactose by galactosidase suppresses the stimulatory
effect of the permease. But the stabilizing effect of dilution also changes
dramatically as a function of the medium composition. For instance, during
growth on TMG/succinate, the dilution rate of the permease is proportional to
its activity, $e$, because the specific growth rate is independent of $e$.
However, during growth on lactose, the permease dilution rate is proportional
to $e^2$ because the specific growth rate is proportional to the specific
lactose uptake rate, which in turn, proportional to $e$. Here, we show that:
(a) This dependence on $e^2$ creates such a strong stabilizing effect that
bistability is virtually impossible during growth on lactose, even in the face
of positive feedback. (b) This stabilizing effect is weakened during growth on
lactose + glucose because the specific growth rate on glucose is independent of
$e$, so that the dilution rate once again contains a term that is proportional
to $e$. We discuss the experimental data in the light of these results.


title:
Discovery of Interstellar Propylene (CH_2CHCH_3): Missing Links in
  Interstellar Gas-Phase Chemistry

abstract:
  We report the discovery of propylene (also called propene, CH_2CHCH_3) with
the IRAM 30-m radio telescope toward the dark cloud TMC-1. Propylene is the
most saturated hydrocarbon ever detected in space through radio astronomical
techniques. In spite of its weak dipole moment, 6 doublets (A and E species)
plus another line from the A species have been observed with main beam
temperatures above 20 mK. The derived total column density of propylene is 4
10^13 cm^-2, which corresponds to an abundance relative to H_2 of 4 10^-9,
i.e., comparable to that of other well known and abundant hydrocarbons in this
cloud, such as c-C_3H_2. Although this isomer of C_3H_6 could play an important
role in interstellar chemistry, it has been ignored by previous chemical models
of dark clouds as there seems to be no obvious formation pathway in gas phase.
The discovery of this species in a dark cloud indicates that a thorough
analysis of the completeness of gas phase chemistry has to be done.


title: Harmonic morphisms and hyperelliptic graphs

abstract:
  We study harmonic morphisms of graphs as a natural discrete analogue of
holomorphic maps between Riemann surfaces. We formulate a graph-theoretic
analogue of the classical Riemann-Hurwitz formula, study the functorial maps on
Jacobians and harmonic 1-forms induced by a harmonic morphism, and present a
discrete analogue of the canonical map from a Riemann surface to projective
space. We also discuss several equivalent formulations of the notion of a
hyperelliptic graph, all motivated by the classical theory of Riemann surfaces.
As an application of our results, we show that for a 2-edge-connected graph G
which is not a cycle, there is at most one involution $\iota$ on G for which
the quotient $G/\iota$ is a tree. We also show that the number of spanning
trees in a graph G is even if and only if G admits a non-constant harmonic
morphism to the graph B_2 consisting of 2 vertices connected by 2 edges.
Finally, we use the Riemann-Hurwitz formula and our results on hyperelliptic
graphs to classify all hyperelliptic graphs having no Weierstrass points.


title:
Spectropolarimetric inversions of the Ca II 8498 A and 8542 A lines in
  the quiet Sun

abstract:
  We study non-LTE inversions of the Ca II infrared triplet lines as a tool for
inferring physical properties of the quiet Sun. The inversion code is
successful in recovering the temperature, velocity and longitudinal magnetic
flux density in the photosphere and chromosphere, but the height range where
the inversions are sensitive is limited, especially in the chromosphere. We
present results of inverting spectropolarimetric observations of the lines in a
quiet Sun region. We find three distinct ranges in chromospheric temperature:
low temperatures in the internetwork, high temperatures in the enhanced
magnetic network and intermediate temperatures associated with low magnetic
flux regions in the network. The differences between these regions become more
pronounced with height as the plasma-$\beta$ decreases. These inversions
support the picture of the chromosphere, especially close to the magnetic
network, being highly inhomogeneous both in the vertical and horizontal
directions.


title: Multiplicity Bounds for Quadratic Monomial Ideals

abstract:
  We prove the multiplicity bounds conjectured by Herzog-Huneke-Srinivasan and
Herzog-Srinivasan in the following cases: the strong conjecture for edge ideals
of bipartite graphs, and the weaker Taylor bound conjecture for all quadratic
monomial ideals. We attach a directed graph to a bipartite graph with perfect
matching, and describe operations on the directed graph that would reduce the
problem to a Cohen-Macaulay bipartite graph. We determine when equality holds
in the conjectured bound for edge ideals of bipartite graphs, and verify that
when equality holds, the resolution is pure. We characterize bipartite graphs
that have Cohen-Macaulay edge ideals and quasi-pure resolutions.


title:
Etude Des Signaux Recueillis Par Un Radar Embarque Sur Un Vehicule En
  Deplacement. Application a L'Interpretation Des Signaux Recoltes Par Le Radar
  Wisdom De la Mission Spatiale Exomars

abstract:
  The ExoMars mission of the program Aurora (ESA) aims to send a vehicle
(Rover) on Mars in 2013. Beyond the technological aspects of the mission, the
Rover will also carry scientific instruments for the analysis of Mars
subsurface to search traces of past or present life in the Martian soil. The
Rover will embark a drilling machine which will give access to samples of
sub-surface of Mars to 2 meters depth. This constitutes the great originality
of ExoMars, because the Mars sub-surface remains still unknown and seems to be
the best place to shelter good conditions to create life. This drilling machine
will be guided by a radar system sounder UHF, the WISDOM instrument, which will
also make possible to probe the Mars sub-surface to a few meters of depth to
detect water and to study the geological structures. We have analytical and
numerical electromagnetic models to simulate the behavior of an electromagnetic
wave in the Mars sub-surface, but also to simulate the interactions between the
wave and the structure of the Rover. The objective of the work which we present
consists in the study of the factors able to create disturbances of
measurements in order to correct the effects on the measured signal. Initially
we present the solution which we retained in order to be able during the same
calculation to simulate the displacement of the Rover on several tens of
meters. We also present the results relating to the effect of the orientation
of the antenna during displacement due to topography of the observation site.


title:
A dichotomy characterizing analytic digraphs of uncountable Borel
  chromatic number in any dimension

abstract:
  We study the extension of the Kechris-Solecki-Todorcevic dichotomy on
analytic graphs to dimensions higher than 2. We prove that the extension is
possible in any dimension, finite or infinite. The original proof works in the
case of the finite dimension. We first prove that the natural extension does
not work in the case of the infinite dimension, for the notion of continuous
homomorphism used in the original theorem. Then we solve the problem in the
case of the infinite dimension. Finally, we prove that the natural extension
works in the case of the infinite dimension, but for the notion of
Baire-measurable homomorphism.


title: Fluorescence during Doppler cooling of a single trapped atom

abstract:
  We investigate the temporal dynamics of Doppler cooling of an initially hot
single trapped atom in the weak binding regime using a semiclassical approach.
We develop an analytical model for the simplest case of a single vibrational
mode for a harmonic trap, and show how this model allows us to estimate the
initial energy of the trapped particle by observing the fluorescence rate
during the cooling process. The experimental implementation of this temperature
measurement provides a way to measure atom heating rates by observing the
temperature rise in the absence of cooling. This method is technically
relatively simple compared to conventional sideband detection methods, and the
two methods are in reasonable agreement. We also discuss the effects of RF
micromotion, relevant for a trapped atomic ion, and the effect of coupling
between the vibrational modes on the cooling dynamics.


title:
Effectiveness and improvement of cylindrical cloaking with the SHS
  lining

abstract:
  We analyze, both analytically and numerically, the effectiveness of cloaking
an infinite cylinder from observations by electromagnetic waves in three
dimensions. We show that, as truncated approximations of the ideal permittivity
and permeability tensors tend towards the singular ideal cloaking fields, so
that the anisotropy ratio tends to infinity, the $D$ and $B$ fields blow up
near the cloaking surface. We also consider cloaking with and without the SHS
(soft-and-hard surface) lining. We demonstrate numerically that cloaking is
significantly improved by the SHS lining, with both the far field of the
scattered wave significantly reduced and the blow up of $D$ and $B$ prevented.


title:
Fast Collisionless Reconnection Condition and Self-Organization of Solar
  Coronal Heating

abstract:
  I propose that solar coronal heating is a self-regulating process that keeps
the coronal plasma roughly marginally collisionless. The self-regulating
mechanism is based on the interplay of two effects. First, plasma density
controls coronal energy release via the transition between the slow collisional
Sweet-Parker regime and the fast collisionless reconnection regime. This
transition takes place when the Sweet--Parker layer becomes thinner than the
characteristic collisionless reconnection scale. I present a simple criterion
for this transition in terms of the upstream plasma density (n_e), the
reconnecting (B_0) and guide (B_z) magnetic field components, and the global
length (L) of the reconnection layer: L < 6.10^9 cm [n_e/(10^{10}/cm^3)]^(-3)
(B_0/30G)^4 (B_0/B_z)^2. Next, coronal energy release by reconnection raises
the ambient plasma density via chromospheric evaporation and this, in turn,
temporarily inhibits subsequent reconnection involving the newly-reconnected
loops. Over time, however, radiative cooling gradually lowers the density again
below the critical value and fast reconnection again becomes possible. As a
result, the density is highly inhomogeneous and intermittent but,
statistically, does not deviate strongly from the critical value which is
comparable with the observed coronal density. Thus, in the long run, the
coronal heating process can be represented by repeating cycles that consist of
fast reconnection events (i.e., nanoflares), followed by rapid evaporation
episodes, followed by relatively long periods (1-hour) during which magnetic
stresses build up and simultaneously the plasma cools down and precipitates.


title: Aspects of M-Theory Brane Interactions and String Theory Symmetries

abstract:
  The dissertation consists of two parts. The first presents an account of the
effective worldvolume description of $N$ coincident M2-branes ending on an
M5-brane in M-theory. It reviews Basu and Harvey's recent description of the
worldvolume theory of the M2-branes in terms of a Bogomol'nyi equation, and its
solution via a fuzzy (three-) funnel. Tests of the consistency of this picture
are then performed and many of the issues with it are addressed. This is
followed by a discussion of how a refinement of the fuzzy three-sphere algebra
used can lead to the correct $N^{3/2}$ scaling of degrees of freedom for this
system. A reduction of this Basu-Harvey picture to the D1-string picture of the
D1-D3 intersection is then performed via constructing a reduction of the
fuzzy-three sphere to the fuzzy two-sphere.
  The second part of the dissertation describes how a holomorphic factorisation
argument can be used to demonstrate quantum equivalence of the doubled
formalism of string theory with the standard formalism by deriving the
partition function, including instanton and oscillator sectors.


title: Surfaces from Circles

abstract:
  In the search for appropriate discretizations of surface theory it is crucial
to preserve such fundamental properties of surfaces as their invariance with
respect to transformation groups. We discuss discretizations based on M\"obius
invariant building blocks such as circles and spheres. Concrete problems
considered in these lectures include the Willmore energy as well as conformal
and curvature line parametrizations of surfaces. In particular we discuss
geometric properties of a recently found discrete Willmore energy. The
convergence to the smooth Willmore functional is shown for special refinements
of triangulations originating from a curvature line parametrization of a
surface. Further we treat special classes of discrete surfaces such as
isothermic and minimal. The construction of these surfaces is based on the
theory of circle patterns, in particular on their variational description.


title:
Quantum Monte Carlo simulations of bosonic and fermionic impurities in a
  two-dimensional hard-core boson system

abstract:
  A two-dimensional lattice hard-core boson system with a small fraction of
bosonic or fermionic impurity particles is studied. The impurities have the
same hopping and interactions as the dominant bosons and their effects are
solely due to quantum statistics. Quantum Monte Carlo simulations are carried
out in which paths of the dominant boson species are sampled and a summation is
performed over all second-species paths compatible with the permutation cycles.
Both kinds of impurities reduce modestly and equally the Kosterliz-Thouless
superfluid transition temperature. However, the effective impurity interactions
are found to be qualitatively different at lower temperatures; fermions are
repulsive and further suppress superfluidity at low temperatures.


title: Cartan and Berwald connections in the pullback formalism

abstract:
  Adopting the pullback approach to global Finsler geometry, the aim of the
present paper is to provide new intrinsic (coordinate-free) proofs of intrinsic
versions of the existence and uniqueness theorems for the Cartan and Berwald
connections on a Finsler manifold. To accomplish this, the notions of semispray
and nonlinear connection associated with a given regular connection, in the
pullback bundle, is introduced and investigated. Moreover, it is shown that for
the Cartan and Berwald connections, the associated semispray coincides with the
canonical spray and the associated nonlinear connection coincides with the
Barthel connection. An explicit intrinsic expression relating both connections
is deduced.


title: An X-ray jet in the BL Lac S5 2007+777

abstract:
  The BL Lac S5 2007+777 was observed by us with Chandra, to find the X-ray
counterpart to its 18" radio jet, and study its structure. Indeed, a bright
X-ray jet was discovered in the 33 ks ACIS-S image of the source. We present
its properties and briefly discuss the implications.


title: Theory of dimension for large discrete sets and applications

abstract:
  We define two notions of discrete dimension based on the Minkowski and
Hausdorff dimensions in the continuous setting. After proving some basic
results illustrating these definitions, we apply this machinery to the study of
connections between the Erdos and Falconer distance problems in geometric
combinatorics and geometric measure theory, respectively.


title: Predictions for sin 2(beta/phi_1)_eff in b->s penguin dominated modes

abstract:
  We provide a review of predictions for sin 2beta_eff in b->s penguin
dominated modes based on 1/m_b expansion and/or SU(3) flavor symmetry. The
experimental results are consistently lower than the theoretical predictions.
In order to interpret whether this effect is a sign of new physics
contributions or can be explained away within the Standard Model a theoretical
input cannot be avoided. The effect survives at a level larger than 2.1 sigma
in a conservative average over different modes that includes theoretical
predictions.


title: Exploring improved holographic theories for QCD: Part I

abstract:
  Various holographic approaches to QCD in five dimensions are explored using
input both from the putative non-critical string theory as well as QCD. It is
argued that a gravity theory in five dimensions coupled to a dilaton and an
axion may capture the important qualitative features of pure QCD. A part of the
higher alpha' corrections are resummed into a dilaton potential. The potential
is shown to be in one-to-one correspondence with the exact beta-function of
QCD, and its knowledge determines the full structure of the vacuum solution.
The geometry near the UV boundary is that of AdS_5 with logarithmic corrections
reflecting the asymptotic freedom of QCD. We find that all relevant confining
backgrounds have an IR singularity of the "good" kind that allows unambiguous
spectrum computations. Near the singularity the 't Hooft coupling is driven to
infinity. Asymptotically linear glueball masses can also be achieved. The
classification of all confining asymptotics, the associated glueball spectra
and meson dynamics are addressed in a companion paper, ArXiv:0707.1349


title: The Norm Index Theorem (An Analytic Proof)

abstract:
  We give an analytic proof of the norm index theorem $[I_:K^* N(I_L)] =[L:K]$
for cyclic extensions of number fields using spectral theory of the idele class
group.


title: New Generalizations of Poisson Algebras

abstract:
  We introduce many new generalizations of Poisson algebras which can be
constructed inside the associative algebra of linear transformations over a
vector space.


title: Comment on "Multiferroicity Induced by Dislocated Spin-Density Waves"

abstract:
  I show that the claims in Phys. Rev. Lett. 98, 257602 by Betouras et al
concerning YMn2O5 are incorect.


title: Evidence for short-lived SN Ia progenitors

abstract:
  We use the VESPA algorithm and spectra from the Sloan Digital Sky Survey to
investigate the star formation history of the host galaxies of 257 Type Ia
supernovae. We find 5$\sigma$ evidence for a short-lived population of
progenitors with lifetimes of less than 180 Myr, indicating a Type Ia supernova
channel arising from stars in the mass range $\sim$3.5-8 $M_\odot$. As
standardizeable candles, Type Ia supernovae play an important role in
determining the expansion history of the Universe, but to be useful for future
cosmological surveys, the peak luminosity needs to be free of uncorrected
systematic effects at the level of 1-2%. If the different progenitor routes
lead to supernovae with even moderately small differences in properties, then
these need to be corrected for separately, or they could lead to a systematic
bias in future supernovae surveys, as the prompt route is likely to increase in
importance at high redshift. VESPA analysis of hosts could be a valuable tool
in this, by identifying which progenitor route is most likely.


title: Fock space, quantum fields and kappa-Poincar\'e symmetries

abstract:
  We study the quantization of a linear scalar field, whose symmetries are
described by the kappa-Poincare' Hopf-algebra, via deformed Fock space
construction. The one-particle sector of the theory exhibits a natural
(planckian) cut-off for the field modes. At the multi-particle level the
non-trivial co-algebra structure of kappa-Poincare' leads to a deformed
bosonization in the construction of Fock space states. These physical states
carry energy-momentum charges which are divergenceless and obey a deformed
dispersion relation.


title:
Proving the triviality of rational points on Atkin-Lehner quotients of
  Shimura curves

abstract:
  In this paper we give a method for studying global rational points on certain
quotients of Shimura curves by Atkin-Lehner involutions. We obtain explicit
conditions on such quotients for rational points to be ``trivial'' (coming from
CM points only) and exhibit an explicit infinite family of such quotients
satisfying these conditions.


title:
Quantum Chaos, Delocalization, and Entanglement in Disordered Heisenberg
  Models

abstract:
  We investigate disordered one- and two-dimensional Heisenberg spin lattices
across a transition from integrability to quantum chaos from both a statistical
many-body and a quantum-information perspective. Special emphasis is devoted to
quantitatively exploring the interplay between eigenvector statistics,
delocalization, and entanglement in the presence of nontrivial symmetries. The
implications of basis dependence of state delocalization indicators (such as
the number of principal components) is addressed, and a measure of {\em
relative delocalization} is proposed in order to robustly characterize the
onset of chaos in the presence of disorder. Both standard multipartite and {\em
generalized entanglement} are investigated in a wide parameter regime by using
a family of spin- and fermion- purity measures, their dependence on
delocalization and on energy spectrum statistics being examined. A distinctive
{\em correlation between entanglement, delocalization, and integrability} is
uncovered, which may be generic to systems described by the two-body random
ensemble and may point to a new diagnostic tool for quantum chaos. Analytical
estimates for typical entanglement of random pure states restricted to a proper
subspace of the full Hilbert space are also established and compared with
random matrix theory predictions.


title:
Suppression of Higgsino mediated proton decay by cancellations in GUTs
  and strings

abstract:
  A mechanism for the enhancement for proton lifetime in
supersymmetric/supergravity (SUSY/SUGRA) grand unified theories (GUTs) and in
string theory models is discussed where Higgsino mediated proton decay arising
from color triplets (anti-triplets) with charges $Q=-1/3(1/3)$ and
$Q=-4/3(4/3)$ is suppressed by an internal cancellation due to contributions
from different sources. We exhibit the mechanism for an SU(5) model with
$45_H+\bar{45}_H$ Higgs multiplets in addition to the usual Higgs structure of
the minimal model. This model contains both $Q=-1/3(1/3)$ and $Q=-4/3(4/3)$
Higgs color triplets (anti-triplets) and simple constraints allow for a
complete suppression of Higgsino mediated proton decay. Suppression of proton
decay in an SU(5) model with Planck scale contributions is also considered. The
suppression mechanism is then exhibited for an SO(10) model with a unified
Higgs structure involving $144_H+\bar{144}_H$ representations.The SU(5)
decomposition of $144_H+\bar{144}_H$ contains $5_H+\bar 5_H$ and
$45_H+\bar{45}_H$ and the cancellation mechanism arises among these
contributions which mirrror the SU(5) case. The cancellation mechanism appears
to be more generally valid for a larger class of unification models.
Specifically the cancellation mechanism may play a role in string model
constructions to suppress proton decay from dimension five operators. The
mechanism allows for the suppression of proton decay consistent with current
data allowing for the possibility that proton decay may be visible in the next
round of nucleon stability experiment.


title: Disproof of Bell's Theorem: Further Consolidations

abstract:
  The failure of Bell's theorem for Clifford algebra valued local variables is
further consolidated by proving that the conditions of remote parameter
independence and remote outcome independence are duly respected within the
recently constructed exact, local realistic model for the EPR-Bohm
correlations. Since the conjunction of these two conditions is equivalent to
the locality condition of Bell, this provides an independent geometric proof of
the local causality of the model, at the level of microstates. In addition to
local causality, the model respects at least seven other conceptual and
operational requirements, arising either from the predictions of quantum
mechanics or the premises of Bell's theorem, including the Malus's law for
sequential spin measurements. Since the agreement between the predictions of
the model and those of quantum mechanics is quantitatively precise in all
respects, the ensemble interpretation of the entangled singlet state becomes
amenable.


title:
Gravitational Wave Recoil and the Retention of Intermediate Mass Black
  Holes

abstract:
  During the inspiral and merger of a binary black hole, gravitational
radiation is emitted anisotropically due to asymmetries in the merger
configuration. This anisotropic radiation leads to a gravitational wave kick,
or recoil velocity, as large as ~ 4000 km/sec. We investigate the effect
gravitational recoil has on the retention of intermediate mass black holes
(IMBH) within Galactic globular clusters. Assuming that our current
understanding of IMBH-formation is correct and yields an IMBH-seed in every
globular cluster, we find a significant problem retaining low mass IMBHs (1000
$\Msun$) in the typical merger-rich globular cluster environment. Given a
uniform black hole spin distribution and orientation and a Kroupa IMF, we find
that at most 3% of the globular clusters can retain an IMBH larger than 1000
$\Msun$ today. For a population of black holes that better approximates mass
loss from winds and supernovae, we find that 16% of globulars can retain an
IMBH larger than 1000 $\Msun$. Our calculations show that if there are black
holes of mass $M > 60 \Msun$ in a cluster, repeated IMBH-BH encounters will
eventually eject a 1000 $\Msun$ IMBH with greater than 30% probability. As a
consequence, a large population of rogue black holes may exist in our Milky Way
halo. We discuss the dynamical implications of this subpopulation, and its
possible connection to ultraluminous X-ray sources (ULXs).


title: Functoriality and special values of L-functions

abstract:
  This is a semi-expository article concerning Langlands functoriality and
Deligne's conjecture on the special values of $L$-functions. The emphasis is on
symmetric power $L$-functions associated to a holomorphic cusp form, while
appealing to a recent work of Mahnkopf on the special values of automorphic
$L$-functions.


title:
Aluminium Nanowires: Influence of Work Hardening on Conductance
  Histograms

abstract:
  Conductance histograms of work-hardened Al show a series up to 11 equidistant
peaks with a period of 1.15 +/- 0.02 of the quantum conductance unit G_0 =
2e^2/h. Assuming the peaks originate from atomic discreteness, this agrees with
the value of 1.16 G_0 per atom obtained in numerical calculations by Hasmy et
al.


title: Root Systems and the Quantum Cohomology of ADE resolutions

abstract:
  We compute the C*-equivariant quantum cohomology ring of Y, the minimal
resolution of the DuVal singularity C^2/G where G is a finite subgroup of
SU(2). The quantum product is expressed in terms of an ADE root system
canonically associated to G. We generalize the resulting Frobenius manifold to
non-simply laced root systems to obtain an n parameter family of algebra
structures on the affine root lattice of any root system. Using the Crepant
Resolution Conjecture, we obtain a prediction for the orbifold Gromov-Witten
potential of [C^2/G].


title:
l-Adic representations associated to modular forms over imaginary
  quadratic fields

abstract:
  Let pi be a regular algebraic cuspidal automorphic representation of GL(2)
over an imaginary quadratic number field K such that the central character of
pi is invariant under the non-trivial automorphism of K. We show that pi is
associated with an l-adic Galois representation rho over K such that at each
prime of K outside an explicit finite set the Frobenius polynomial of rho
agrees with the Hecke polynomial of pi.


title: Finding the Charge of the top quark in the Dilepton Channel

abstract:
  There is a question about the identity of the top quark. Is it the top quark
of the Standard Model (SM) with electric charge 2/3 or is it an exotic quark
with charge -4/3? An exotic quark has been proposed by D. Chang et
al.\cite{hep-ph/9810531, hep-ph/9805273}. This analysis will use the standard
CDF run II dilepton sample. The key ingredients of this analysis are the
correct pairing of the lepton and b-jet, the determination of the charge of the
b-jet. The analysis proceeds by using a binomial distribution and is formulated
so that rejecting one hypothesis means support for the other hypothesis.


title: Plasma Suppression of Large Scale Structure Formation in the Universe

abstract:
  We point out that during the reionization epoch of the cosmic history, the
plasma collective effect among the ordinary matter would suppress the large
scale structure formation. The imperfect Debye shielding at finite temperature
would induce a residual long-range electrostatic potential which, working
together with the baryon thermal pressure, would counter the gravitational
collapse. As a result the effective Jean's length, $\tilde{\lambda}_J$, is
increased by a factor, $\tilde{\lambda}_J/\lambda_J=\sqrt{8/5}$, relative to
the conventional one. For scales smaller than the effective Jean's scale the
plasma would oscillate at the ion-acoustic frequency. The modes that would be
influenced by this effect depend on the starting time and the initial
temperature of reionization, but roughly lie in the range $0.5 h{\rm Mpc}^{-1}<
k$, which corresponds to the region of the Lyman-$\alpha$ forest from the
inter-galactic medium. We predict that in the linear regime of density-contrast
growth, the plasma suppression of the matter power spectrum would approach
$1-(\Omega_{dm}/\Omega_m)^2\sim 1-(5/6)^2\sim 30%$.


title: Coherence of an optically illuminated single nuclear spin qubit

abstract:
  We investigate the coherence properties of individual nuclear spin quantum
bits in diamond [Dutt et al., Science, 316, 1312 (2007)] when a proximal
electronic spin associated with a nitrogen-vacancy (NV) center is being
interrogated by optical radiation. The resulting nuclear spin dynamics are
governed by time-dependent hyperfine interaction associated with rapid
electronic transitions, which can be described by a spin-fluctuator model. We
show that due to a process analogous to motional averaging in nuclear magnetic
resonance, the nuclear spin coherence can be preserved after a large number of
optical excitation cycles. Our theoretical analysis is in good agreement with
experimental results. It indicates a novel approach that could potentially
isolate the nuclear spin system completely from the electronic environment.


title: Top Quark Production and Decay Properties at the Tevatron

abstract:
  The latest results from the CDF and D0 collaborations on the top-quark
pair-production cross section and limits on electroweak production are
presented. Included are measurements of properties of the top quark such as
charge, lifetime, and the decay branching ratio t->Wb. In addition to
measurements about the top quark, the selected event samples are used to study
the helicity of the W boson and to search for additional exotic quarks (t') and
resonances in the ttbar invariant mass spectrum.


title: Albus 1: A very bright white dwarf candidate

abstract:
  We have serendipitously discovered a previously-unknown, bright source (B_T =
11.75+/-0.07 mag) with a very blue V_T-K_s color, to which we have named Albus
1. A photometric and astrometric study using Virtual Observatory tools has
shown that it possesses an appreciable proper motion and magnitudes and colors
very similar to those of the well known white dwarf G 191-B2B. We consider
Albus 1 as a DA-type white dwarf located at about 40 pc. If confirmed its
nature, Albus 1 would be the sixth brightest isolated white dwarf in the sky,
which would make it an excellent spectrophotometric standard.


title: Piecewise principal comodule algebras

abstract:
  A comodule algebra P over a Hopf algebra H with bijective antipode is called
principal if the coaction of H is Galois and P is H-equivariantly projective
(faithfully flat) over the coaction-invariant subalgebra B. We prove that
principality is a piecewise property: given N comodule-algebra surjections
P->Pi whose kernels intersect to zero, P is principal if and only if all Pi's
are principal. Furthermore, assuming the principality of P, we show that the
lattice these kernels generate is distributive if and only if so is the lattice
obtained by intersection with B. Finally, assuming the above distributivity
property, we obtain a flabby sheaf of principal comodule algebras over a
certain space that is universal for all such N-families of surjections P->Pi
and such that the comodule algebra of global sections is P.


title: Loss of star forming gas in SDSS galaxies

abstract:
  Using the star formation rates from the SDSS galaxy sample, extracted using
the MOPED algorithm, and the empirical Kennicutt law relating star formation
rate to gas density, we calculate the time evolution of the gas fraction as a
function of the present stellar mass. We show how the gas-to-stars ratio varies
with stellar mass, finding good agreement with previous results for smaller
samples at the present epoch. For the first time we show clear evidence for
progressive gas loss with cosmic epoch, especially in low-mass systems. We find
that galaxies with small stellar masses have lost almost all of their cold
baryons over time, whereas the most massive galaxies have lost little. Our
results also show that the most massive galaxies have evolved faster and turned
most of their gas into stars at an early time, thus strongly supporting a
downsizing scenario for galaxy evolution.


title:
Role of Charged Gauge Fields in Generating Magnetic Seed Fields in
  Bubble Collisions during the Cosmological Electroweak Phase Transition

abstract:
  We calculate the magnetic field generated during bubble collisions in a
first-order electroweak phase transition that may occur for some choices of
parameters in the minimal supersymmetric Standard Model. We show that for
sufficiently gentle collisions, where the Higgs field is relatively unperturbed
in the bubble overlap region, the equations of motion can be linearized so that
in the absence of fermions the charged W fields are the source of the
electromagnetic current for generating the seed fields. Solutions of the
equations of motion for the charged gauge fields and Maxwell's equations for
the magnetic field in O(1,2) space-time symmetry are expressed in closed form
by applying boundary conditions at the time of collision. Our results indicate
that the magnetic fields generated by charged $W^{\pm}$ fields in the collision
are comparable to those found in previous work. The magnetic fields so produced
could seed galactic and extra-galactic magnetic fields observed today.


title:
Spitzer IRAC observations of newly-discovered planetary nebulae from the
  Macquarie-AAO-Strasbourg H-alpha Planetary Nebula Project

abstract:
  We compare H-alpha, radio continuum, and Spitzer Space Telescope (SST) images
of 58 planetary nebulae (PNe) recently discovered by the Macquarie-AAO-Strasbo-
urg H-alpha PN Project (MASH) of the SuperCOSMOS H-alpha Survey. Using InfraRed
Array Camera (IRAC) data we define the IR colors of PNe and demonstrate good
isolation between these colors and those of many other types of astronomical
object. The only substantive contamination of PNe in the color-color plane we
illustrate is due to YSOs. However, this ambiguity is readily resolved by the
unique optical characteristics of PNe and their environs. We also examine the
relationships between optical and MIR morphologies from 3.6 to 8.0um and
explore the ratio of mid-infrared (MIR) to radio nebular fluxes, which is a
valuable discriminant between thermal and nonthermal emission. MASH emphasizes
late evolutionary stages of PNe compared with previous catalogs, enabling study
of the changes in MIR and radio flux that attend the aging process. Spatially
integrated MIR energy distributions were constructed for all MASH PNe observed
by the GLIMPSE Legacy Project, using the H-alpha morphologies to establish the
dimensions for the calculations of the Midcourse Space Experiment (MSX), IRAC,
and radio continuum (from the Molonglo Observatory Synthesis Telescope and the
Very Large Array) flux densities. The ratio of IRAC 8.0-um to MSX 8.3-um flux
densities provides a measure of the absolute diffuse calibration of IRAC at 8.0
um. We independently confirm the aperture correction factor to be applied to
IRAC at 8.0um to align it with the diffuse calibration of MSX. The result
agrees with the recommendations of the Spitzer Science Center and with results
from a parallel study of HII regions. These PNe probe the diffuse calibration
of IRAC on a spatial scale of 9-77 arcsec.


title:
Engineering Quantum States of a Nano-Resonator via a Simple Auxiliary
  System

abstract:
  We show how to engineer an extensive range of non-linear Hamiltonians for a
nano-mechanical resonator. The technique requires only a time dependent drive
applied to a Cooper-pair box or second oscillator to which the nano-resonator
is coupled. This method allows one to generate a large number of non-classical
states, as well as Hamiltonians whose classical counterparts are chaotic.


title: Exploring improved holographic theories for QCD: Part II

abstract:
  This paper is a continuation of ArXiv:0707.1324 where improved holographic
theories for QCD were set up and explored. Here, the IR confining geometries
are classified and analyzed. They all end in a "good" (repulsive) singularity
in the IR. The glueball spectra are gaped and discrete, and they favorably
compare to the lattice data. Quite generally, confinement and discrete spectra
imply each other. Asymptotically linear glueball masses can also be achieved.
Asymptotic mass ratios of various glueballs with different spin also turn out
to be universal. Mesons dynamics is implemented via space filling D4-anti-D4
brane pairs. The associated tachyon dynamics is analyzed and chiral symmetry
breaking is shown. The dynamics of the RR axion is analyzed, and the
non-perturbative running of the QCD theta-angle is obtained. It is shown to
always vanish in the IR.


title: Cosmological expansion and local physics

abstract:
  The interplay between cosmological expansion and local attraction in a
gravitationally bound system is revisited in various regimes. First, weakly
gravitating Newtonian systems are considered, followed by various exact
solutions describing a relativistic central object embedded in a Friedmann
universe. It is shown that the ``all or nothing'' behaviour recently discovered
(i.e., weakly coupled systems are comoving while strongly coupled ones resist
the cosmic expansion) is limited to the de Sitter background. New exact
solutions are presented which describe black holes perfectly comoving with a
generic Friedmann universe. The possibility of violating cosmic censorship for
a black hole approaching the Big Rip is also discussed.