title: Reheating-volume measure in the landscape

abstract:
  I recently proposed the "reheating-volume" (RV) prescription as a possible
solution to the measure problem in "multiverse" cosmology. The goal of this
work is to extend the RV measure to scenarios involving bubble nucleation, such
as the string theory landscape. In the spirit of the RV prescription, I propose
to calculate the distribution of observable quantities in a landscape that is
conditioned in probability to nucleate a finite total number of bubbles to the
future of an initial bubble. A general formula for the relative number of
bubbles of different types can be derived. I show that the RV measure is
well-defined and independent of the choice of the initial bubble type, as long
as that type supports further bubble nucleation. Applying the RV measure to a
generic landscape, I find that the abundance of Boltzmann brains is always
negligibly small compared with the abundance of ordinary observers in the
bubbles of the same type. As an illustration, I present explicit results for a
toy landscape containing four vacuum states and for landscapes with a single
high-energy vacuum and a large number of low-energy vacua.


title: Forecasting Cosmological Constraints from Redshift Surveys

abstract:
  Observations of redshift-space distortions in spectroscopic galaxy surveys
offer an attractive method for observing the build-up of cosmological
structure, which depends both on the expansion rate of the Universe and our
theory of gravity. In this paper we present a formalism for forecasting the
constraints on the growth of structure which would arise in an idealized
survey. This Fisher matrix based formalism can be used to study the power and
aid in the design of future surveys.


title: Suzaku Observations of Cyg X-1

abstract:
  We present highlights from a series of four simultaneous Suzaku/RXTE
observations of the black hole candidate Cyg X-1. We briefly summarize several
key results from our decade long RXTE monitoring campaign. We then comment on
challenges of analyzing the Suzaku data, i.e., improving the aspect correction
beyond that of the existing tools, and quantitatively assessing pileup. All of
our Suzaku observations (one, by design) occurred at or very near orbital phase
0 (superior conjunction), and hence show evolution in color-color diagrams due
to X-ray absorption by material from the wind of the secondary. We present
simple partial absorption models for this evolution. We then compare the Suzaku
and RXTE data, and explicitly divide the Fe line region into narrow and broad
components. Both are required for the Suzaku data, and are seen to be
consistent with the RXTE data. These Suzaku observations occurred near
historically hard, low flux states. We present fits of the broad band spectra
with a simple phenomenological broken powerlaw model, as well as a more
physically motivated Comptonization model. Whereas the former class of models
described nearly all of the RXTE campaign better than any physical model, here
the latter model is slightly more successful. The Comptonization model,
however, exhibits little evidence for a soft disk component, which formally
corresponds to a small, inner disk radius. Whether this is physical, due to
unmodeled absorption, or is a calibration issue, remains an open question.


title:
Long-Term Evolution of and X-ray Emission from a Recoiling Supermassive
  Black Hole in a Disk Galaxy

abstract:
  Recent numerical relativity simulations have shown that the emission of
gravitational waves at the merger of two black holes gives a recoil kick to the
final black hole. We follow the orbits of a recoiling supermassive black hole
(SMBH) in a fixed background potential of a disk galaxy including the effect of
dynamical friction. If the recoil velocity of the SMBH is smaller than the
escape velocity of the galaxy, the SMBH moves around in the potential along a
complex trajectory before it spirals into the galactic center through dynamical
friction. We consider the accretion of gas onto the SMBH from the surrounding
ISM and estimate the X-ray luminosity of the SMBH. We find that it can be
larger than 3x 10^39 erg^-1 or the typical X-ray luminosity of ultra-luminous
X-ray sources, when the SMBH passes the galactic disk. In particular, the
luminosity could exceed ~10^46 erg s^-1, if the SMBH is ejected into the
galactic disk. The average luminosity gradually increases as the SMBH spirals
into the galactic center. We also estimate the probability of finding recoiling
SMBHs with X-ray luminosities of >3x 10^39 erg^-1 in a disk galaxy.


title: The Mass and Radius of the Neutron Star in EXO 1745-248

abstract:
  Bursting X-ray binaries in globular clusters are ideal sources for measuring
neutron star masses and radii, and hence, for determining the equation of state
of cold, ultradense matter. We use time-resolved spectroscopic data from EXO
1745-248 during thermonuclear bursts that show strong evidence for photospheric
radius expansion to measure the Eddington flux and the apparent surface area of
the neutron star. We combine this with the recent measurement of the distance
to the globular cluster Terzan 5, where this source resides, to measure the
neutron star mass and radius. We find tightly constrained pairs of values for
the mass and radius, which are centered around M=1.4 M_sun and R=11 km or
around M=1.7 M_sun and R=9 km. These values favor nucleonic equations of state
with symmetry energy that is relatively low and has a weak dependence on
density.


title: The Diversity and Similarity of Simulated Cold Dark Matter Halos

abstract:
  We study the mass, velocity dispersion, and anisotropy profiles of
$\Lambda$CDM halos using a suite of N-body simulations of unprecedented
numerical resolution (the {\it Aquarius Project}). Our analysis confirms a
number of results claimed by earlier work, and clarifies a few issues where
conflicting claims may be found in the recent literature. The
spherically-averaged density profile becomes progressively shallower inwards
and, at the innermost resolved radius, the logarithmic slope is $\gamma \equiv
-$d$\ln\rho/$d$\ln r \simlt 1$. Asymptotic inner slopes as steep as the
recently claimed $\rho \propto r^{-1.2}$ are clearly ruled out. The radial
dependence of $\gamma$ is well approximated by a power-law, $\gamma \propto
r^{\alpha}$ (the Einasto profile). The shape parameter, $\alpha$, varies
slightly but significantly from halo to halo, implying that the mass profiles
of $\Lambda$CDM halos are not strictly universal: different halos cannot, in
general, be rescaled to look identical. Departures from similarity are also
seen in velocity dispersion profiles and correlate with those in density
profiles so as to preserve a power-law form for the spherically averaged
pseudo-phase-space density, $\rho/\sigma^3\propto r^{-1.875}$. Our conclusions
are reliable down to radii below 0.4% of the virial radius, providing
well-defined predictions for halo structure when baryonic effects are
neglected, and thus an instructive theoretical template against which the
modifications induced by the baryonic components of real galaxies can be
judged.


title: The 2007 outburst of the X-ray binary XTE J1856+053

abstract:
  On 28 February 2007 a new outburst of the previously known transient source
XTE J1856+053 was detected with RXTE/ASM. We present here the results of an
XMM-Newton (0.5-10.0 keV) Target of Opportunity observation performed on 14
March 2007, aimed at constraining the mass of the compact object in this X-ray
binary and determining its main properties. The EPIC-pn camera was used in
Timing mode and its spectrum fit together with the RGS data. IR observations
with GROND at the 2.2 m telescope in La Silla provide further information on
the system. The X-ray light curve shows that both the 1996 and the 2007
outbursts had two peaks. The X-ray spectrum is well fit with a thermal
accretion disk model, with kT=0.75+/-0.01 keV and foreground absorption
N_H=4.5(+/-0.1)E22 cm**-2. The low disk temperature favours a black-hole as
accreting object, with an estimated mass in the range 1.3-4.2 M_sun. From the
IR upper limits we argue that XTE J1856+053 is a low mass X-ray binary. We
estimate the orbital period of the system to be between 3 and 12 hours.


title: Phenomenology of iQuarkonium

abstract:
  Phenomenology of uncolored iquarks - hypothetical fermions charged under a
new confining unbroken non-abelian gauge group as well as the standard
electroweak gauge group - is investigated for the iquark mass in the range near
and above 100 GeV. If the new confining scale turns out to be higher than MeV
but much less than the iquark mass, the iquark-antiiquark pair produced in the
collider will promptly relaxed into the ground state of the iquarkonium.
Subsequent pair annihilation into standard model particles gives useful
information of the iquark dynamics. We formulate in details production and
decays of the iquark-antiiquark bound states. Decay patterns of the iquarkonium
can be distinguished from the superheavy quarkonium of a sequential fourth
generation of quarks with degenerate mass.


title: Levy Flights of Binary Orbits due to Impulsive Encounters

abstract:
  We examine the evolution of an almost circular Keplerian orbit interacting
with unbound perturbers. We calculate the change in eccentricity and angular
momentum that results from a single encounter, assuming the timescale for the
interaction is shorter than the orbital period. The orbital perturbations are
incorporated into a Boltzmann equation that allows for eccentricity
dissipation. We present an analytic solution to the Boltzmann equation that
describes the distribution of orbital eccentricity and relative inclination as
a function of time. The eccentricity and inclination of the binary do not
evolve according to a normal random walk but perform a Levy flight. The slope
of the mass spectrum of perturbers dictates whether close gravitational
scatterings are more important than distant tidal ones. When close scatterings
are important, the mass spectrum sets the slope of the eccentricity and
inclination distribution functions. We use this general framework to understand
the eccentricities of several Kuiper belt systems: Pluto, 2003 EL 61, and Eris.
We use the model of Tholen et al (2007) to separate the non-Keplerian
components of the orbits of Pluto's outer moons Nix and Hydra from the motion
excited by interactions with other Kuiper belt objects. Our distribution is
consistent with the observations of Nix, Hydra, and the satellites of 2003 EL
61 and Eris. We address applications of this work to objects outside of the
solar system, such as extrasolar planets around their stars and millisecond
pulsars.


title: Characterizing hyperbolic spaces and real trees

abstract:
  Let X be a geodesic metric space. Gromov proved that there exists k>0 such
that if every sufficiently large triangle T satisfies the Rips condition with
constant k times pr(T), where pr(T) is the perimeter T, then X is hyperbolic.
We give an elementary proof of this fact, also giving an estimate for k. We
also show that if all the triangles T in X satisfy the Rips condition with
constant k times pr(T), then X is a real tree.
  Moreover, we point out how this characterization of hyperbolicity can be used
to improve a result by Bonk, and to provide an easy proof of the (well-known)
fact that X is hyperbolic if and only if every asymptotic cone of X is a real
tree.


title: Pulsars as the Sources of High Energy Cosmic Ray Positrons

abstract:
  Recent results from the PAMELA satellite indicate the presence of a large
flux of positrons (relative to electrons) in the cosmic ray spectrum between
approximately 10 and 100 GeV. As annihilating dark matter particles in many
models are predicted to contribute to the cosmic ray positron spectrum in this
energy range, a great deal of interest has resulted from this observation.
Here, we consider pulsars (rapidly spinning, magnetized neutron stars) as an
alternative source of this signal. After calculating the contribution to the
cosmic ray positron and electron spectra from pulsars, we find that the
spectrum observed by PAMELA could plausibly originate from such sources. In
particular, a significant contribution is expected from the sum of all mature
pulsars throughout the Milky Way, as well as from the most nearby mature
pulsars (such as Geminga and B0656+14). The signal from nearby pulsars is
expected to generate a small but significant dipole anisotropy in the cosmic
ray electron spectrum, potentially providing a method by which the Fermi
gamma-ray space telescope would be capable of discriminating between the pulsar
and dark matter origins of the observed high energy positrons.


title: First-order flow equations for extremal and non-extremal black holes

abstract:
  We derive a general form of first-order flow equations for extremal and
non-extremal, static, spherically symmetric black holes in theories with
massless scalars and vectors coupled to gravity. By rewriting the action as a
sum of squares a la Bogomol'nyi, we identify the function governing the
first-order gradient flow, the `generalised superpotential', which reduces to
the `fake superpotential' for non-supersymmetric extremal black holes and to
the central charge for supersymmetric black holes. For theories whose scalar
manifold is a symmetric space after a timelike dimensional reduction, we
present the condition for the existence of a generalised superpotential. We
provide examples to illustrate the formalism in four and five spacetime
dimensions.


title:
The method of the weakly conjugate operator: Extensions and applications
  to operators on graphs and groups

abstract:
  In this review we present some recent extensions of the method of the weakly
conjugate operator. We illustrate these developments through examples of
operators on graphs and groups.


title: NuFact08 -- Closing Talk

abstract:
  Nufact08 is the tenth in a series of workshops started in 1999, whose main
goal is to understand options for future neutrino-oscillation experiments to
attack the problems of the neutrino mass hierarchy and CP violation in the
leptonic sector. I present a very brief review of what we know and what we
would like to know about neutrino mass, mixing, and flavor change. I consider
the interplay between neutrino physics and forthcoming information from the
Large Hadron Collider. I comment on a decade's progress and offer some context
for work that lies ahead.


title:
Radiation-magnetohydrodynamic simulations of the photoionisation of
  magnetised globules

abstract:
  We present the first three-dimensional radiation-magnetohydrodynamic
simulations of the photoionisation of a dense, magnetised molecular globule by
an external source of ultraviolet radiation. We find that, for the case of a
strong ionising field, significant deviations from the non-magnetic evolution
are seen when the initial magnetic field threading the globule has an
associated magnetic pressure that is greater than one hundred times the gas
pressure. In such a strong-field case, the photoevaporating globule will adopt
a flattened or "curled up" shape, depending on the initial field orientation,
and magnetic confinement of the ionised photoevaporation flow can lead to
recombination and subsequent fragmentation during advanced stages of the
globule evolution. We find suggestive evidence that such magnetic effects may
be important in the formation of bright, bar-like emission features in H II
regions. We include simple but realistic fits to heating and cooling rates in
the neutral and molecular gas in the vicinity of a high-mass star cluster and
show that the frequently used isothermal approximation can lead to an
overestimate of the importance of gravitational instability in the radiatively
imploded globule. For globules within 2 parsecs of a high-mass star cluster, we
find that heating by stellar x rays prevents the molecular gas from cooling
below 50 K.


title:
Quivers with relations arising from Koszul algebras of $\mathfrak
  g$-invariants

abstract:
  Let $\mathfrak g$ be a complex simple Lie algebra and let $\Psi$ be an
extremal set of positive roots. One associates with $\Psi$ an infinite
dimensional Koszul algebra $\bold S_\Psi^{\lie g}$ which is a graded subalgebra
of the locally finite part of $((\bold V)^{op}\tensor S(\lie g))^{\lie g}$,
where $\bold V$ is the direct sum of all simple finite dimensional $\lie
g$-modules. We describe the structure of the algebra $\bold S_\Psi^{\lie g}$
explicitly in terms of an infinite quiver with relations for $\lie g$ of types
$A$ and $C$. We also describe several infinite families of quivers and finite
dimensional algebras arising from this construction.


title: On the regularization of conservative maps

abstract: We show that smooth maps are $C^1$-dense among $C^1$ volume preserving maps.


title: Braneworld Black Holes

abstract:
  In this thesis we investigate black holes in the Randall-Sundrum braneworld
scenario. We begin with an overview of extra-dimensional physics, from the
original proposal of Kaluza and Klein up to the modern braneworld picture of
extra dimensions. A detailed description of braneworld gravity is given, with
particular emphasis on its compatibility with experimental tests of gravity. We
then move on to a discussion of static, spherically symmetric braneworld black
hole solutions. Assuming an equation of state for the ``Weyl term'', which
encodes the effects of the extra dimension, we are able to classify the general
behaviour of these solutions. We then use the strong field limit approach to
investigate the gravitational lensing properties of some candidate braneworld
black hole solutions. It is found that braneworld black holes could have
significantly different observational signatures to the Schwarzschild black
hole of standard general relativity. Rotating braneworld black hole solutions
are also discussed, and we attempt to generate rotating solutions from known
static solutions using the Newman-Janis complexification ``trick''.


title: On the accuracy of the high redshift cluster luminosity function

abstract:
  We study the reliability of the statistical background subtraction method for
computing the Ks-band luminosity function of cluster galaxies at z~1 using mock
Red-sequence Cluster Survey cluster catalogues constructed from GALFORM
semi-analytic galaxies. The underlying cluster luminosity function in the mocks
are compatible with recent estimates at z~1 by several authors. We simulate
different samples where the number of clusters with Ks-band photometry goes
from 5 to a maximum of 50, in order to find the most suitable observational
sample to carry out this study; the current observational status in the nIR
wavelength range has been reached using 5 real clusters at z~1. We compute the
composite luminosity function for several samples of galaxy clusters with
masses 1.5x10^14 M_sun assuming a flux limited, complete sample of galaxies
down to Ks=21.0 magnitudes. We find that the Schechter fit parameters Ks* and
alpha for a sample of galaxies with no redshift information are rather poorly
constrained if both parameters are allowed to vary freely; if alpha is fixed at
a fiducial value, then Ks* shows significantly improved stochastic
uncertainties but can be influenced by systematic deviations. We find a
significantly improved accuracy in the luminosity function parameters when
adding photometric redshift information for bright cluster galaxies. The
dwarf-to-giant ratios inferred from the luminosity functions of red-sequence
galaxies in the mock catalogue agree very well with the underlying values.
Finally, we find that in order to use estimates of Ks* to study the formation
redshift of cluster galaxies at z=1, the sample would need to contain 520 z~1
clusters, for an accuracy of 2 Gyr at the 68 per cent confidence level.


title: Non Abelian gauge theories, prepotentials and Abelian differentials

abstract:
  I discuss particular solutions of the integrable systems, starting from
well-known dispersionless KdV and Toda hierarchies, which define in most
straightforward way the generating functions for the Gromov-Witten classes in
terms of the rational complex curve. On the ``mirror'' side these generating
functions can be identified with the simplest prepotentials of complex
manifolds, and I present few more exactly calculable examples of them. For the
higher genus curves, corresponding in this context to the non Abelian gauge
theories via the topological gauge/string duality, similar solutions are
constructed using extended basis of Abelian differentials, generally with extra
singularities at the branching points of the curve.


title:
Finite size fluctuations and stochastic resonance in globally coupled
  bistable systems

abstract:
  The dynamics of a system formed by a finite number $N$ of globally coupled
bistable oscillators and driven by external forces is studied focusing on a
global variable defined as the arithmetic mean of each oscillator variable.
Several models based on truncation schemes of a hierarchy of stochastic
equations for a set of fluctuating cumulant variables are presented. This
hierarchy is derived using It\^o stochastic calculus, and the noise terms in it
are treated using an asymptotic approximation valid for large $N$. In addition,
a simplified one-variable model based on an effective potential is also
considered. These models are tested in the framework of the phenomenon of
stochastic resonance. In turn, they are used to explain in simple terms the
very large gains recently observed in these finite systems.


title: Anti-vortex dynamics in magnetic nanostripes

abstract:
  In a thin magnetic nanostripe, an anti-vortex nucleates inside a moving
domain wall when driven by an in-plane magnetic field greater than the
so-called Walker field. The nucleated anti-vortex must cross the width of the
nanostripe before the domain wall can propagate again, leading to low average
domain wall speeds. A large out-of-plane magnetic field, applied
perpendicularly to the plane of the nanostripe, inhibits the nucleation of the
anti-vortex leading to fast domain wall speeds for all in-plane driving fields.
We present micromagnetic simulation results relating the anti-vortex dynamics
to the strength of the out-of-plane field. An asymmetry in the motion is
observed which depends on the alignment of the anti-vortex core magnetic
moments to the direction of the out-of-plane field. The size of the core is
directly related to its crossing speed, both depending on the strength of the
perpendicular field and the alignment of the core moments and direction of the
out-of-plane field.


title: The Fundamental Group of Balanced Simplicial Complexes and Posets

abstract:
  We establish an upper bound on the cardinality of a minimal generating set
for the fundamental group of a large family of connected, balanced simplicial
complexes and, more generally, simplicial posets.


title:
Performance Analysis of 60nm gate length III-V InGaAs HEMTs: Simulations
  vs. experiments

abstract:
  An analysis of recent experimental data for high-performance In0.7Ga0.3As
high electron mobility transistors (HEMTs) is presented. Using a fully quantum
mechanical, ballistic model, we simulate In0.7Ga0.3As HEMTs with gate lengths
of LG = 60nm, 85, and 135 nm and compare the result to the measured I-V
characteristics including draininduced barrier lowering, sub-threshold swing,
and threshold voltage variation with gate insulator thickness, as well as
on-current performance. To first order, devices with three different oxide
thicknesses and channel lengths can all be described by our ballistic model
with appropriate values of parasitic series resistance. For high gate voltages,
however, the ballistic simulations consistently overestimate the measured
on-current, and they do not show the experimentally observed decrease in
on-current with increasing gate length. With no parasitic series resistance at
all, the simulated on-current of the LG = 60 nm device is about twice the
measured current. According to the simulation, the estimated ballistic carrier
injection velocity for this device is about 2.7 x 10^7 cm/s. Because of the
importance of the semiconductor capacitance, the simulated gate capacitance is
about 2.5 times less than the insulator capacitance. Possible causes of the
transconductance degradation observed under high gate voltages in these devices
are also explored. In addition to a possible gate-voltage dependent scattering
mechanism, the limited ability of the source to supply carriers to the channel,
and the effect of nonparabolicity are likely to play a role. The drop in
on-current with increasing gate length is an indication that the devices
operate below the ballistic limit.


title: Absolute properties of the low-mass eclipsing binary CM Draconis

abstract:
  Spectroscopic and eclipsing binary systems offer the best means for
determining accurate physical properties of stars, including their masses and
radii. The data available for low-mass stars have yielded firm evidence that
stellar structure models predict smaller radii and higher effective
temperatures than observed, but the number of systems with detailed analyses is
still small. In this paper we present a complete reanalysis of one of such
eclipsing systems, CM Dra, composed of two dM4.5 stars. New and existing light
curves as well as a radial velocity curve are modeled to measure the physical
properties of both components. The masses and radii determined for the
components of CM Dra are M1=0.2310+/-0.0009 Msun, M2=0.2141+/-0.0010 Msun,
R1=0.2534+/-0.0019 Rsun, and R2=0.2396+/-0.0015 Rsun. With relative
uncertainties well below the 1% level, these values constitute the most
accurate properties to date for fully convective stars. This makes CM Dra a
valuable benchmark for testing theoretical models. In comparing our
measurements with theory, we confirm the discrepancies reported previously for
other low-mass eclipsing binaries. These discrepancies seem likely to be due to
the effects of magnetic activity. We find that the orbit of this system is
slightly eccentric, and we have made use of eclipse timings spanning three
decades to infer the apsidal motion and other related properties.


title: Kernel algebras and generalized Fourier-Mukai transforms

abstract:
  We introduce and study kernel algebras, i.e., algebras in the category of
sheaves on a square of a scheme, where the latter category is equipped with a
monoidal structure via a natural convolution operation. We show that many
interesting categories, such as D-modules, equivariant sheaves and their
twisted versions, arise as categories of modules over kernel algebras. We
develop the techniques of constructing derived equivalences between these
module categories. As one application we generalize the results of
math.AG/9901009 concerning modules over algebras of twisted differential
operators on abelian varieties. As another application we recover and
generalize the results of Laumon in alg-geom/9603004 concerning an analog of
the Fourier transform for derived categories of quasicoherent sheaves on a dual
pair of generalized 1-motives.


title: On the nonlocality of the fractional Schr\"{o}dinger equation

abstract:
  A number of papers over the past eight years have claimed to solve the
fractional Schr\"{o}dinger equation for systems ranging from the
one-dimensional infinite square well to the Coulomb potential to
one-dimensional scattering with a rectangular barrier. However, some of the
claimed solutions ignore the fact that the fractional diffusion operator is
inherently nonlocal, preventing the fractional Schr\"{o}dinger equation from
being solved in the usual piecewise fashion. We focus on the one-dimensional
infinite square well and show that the purported groundstate, which is based on
a piecewise approach, is definitely not a solution of the fractional
Schr\"{o}dinger equation for general fractional parameters $\alpha$. On a more
positive note, we present a solution to the fractional Schr\"{o}dinger equation
for the one-dimensional harmonic oscillator with $\alpha=1$.


title:
Mechanism, dynamics, and biological existence of multistability in a
  large class of bursting neurons

abstract:
  Multistability, the coexistence of multiple attractors in a dynamical system,
is explored in bursting nerve cells. A modeling study is performed to show that
a large class of bursting systems, as defined by a shared topology when
represented as dynamical systems, is inherently suited to support
multistability. We derive the bifurcation structure and parametric trends
leading to multistability in these systems. Evidence for the existence of
multirhythmic behavior in neurons of the aquatic mollusc Aplysia californica
that is consistent with our proposed mechanism is presented. Although these
experimental results are preliminary, they indicate that single neurons may be
capable of dynamically storing information for longer time scales than
typically attributed to nonsynaptic mechanisms.


title: The Incompressible Non-Relativistic Navier-Stokes Equation from Gravity

abstract:
  We note that the equations of relativistic hydrodynamics reduce to the
incompressible Navier-Stokes equations in a particular scaling limit. In this
limit boundary metric fluctuations of the underlying relativistic system turn
into a forcing function identical to the action of a background electromagnetic
field on the effectively charged fluid. We demonstrate that special conformal
symmetries of the parent relativistic theory descend to `accelerated boost'
symmetries of the Navier-Stokes equations, uncovering a possibly new conformal
symmetry structure of these equations. Applying our scaling limit to
holographically induced fluid dynamics, we find gravity dual descriptions of an
arbitrary solution of the forced non-relativistic incompressible Navier-Stokes
equations. In the holographic context we also find a simple forced steady state
shear solution to the Navier-Stokes equations, and demonstrate that this
solution turns unstable at high enough Reynolds numbers, indicating a possible
eventual transition to turbulence.


title:
Necessity of mixed kinetic term in the description of general system
  with identical fields

abstract:
  Most general renormalizable interaction in the system with a set of scalar
fields having identical quantum numbers generates naturally mixed kinetic terms
in the Lagrangian. Taking into account these terms leads to modification both
the renormalization group equations and the tree level analysis as compare with
many published results. We obtain conditions for non-appearance of such a
running mixing in some important cases.


title: Conditional Limit Results for Type I Polar Distributions

abstract:
  Let (S_1,S_2)=(R \cos(\Theta), R \sin (\Theta)) be a bivariate random vector
with associated random radius R which has distribution function $F$ being
further independent of the random angle \Theta. In this paper we investigate
the asymptotic behaviour of the conditional survivor probability
\Psi_{\rho,u}(y):=\pk{\rho S_1+ \sqrt{1- \rho^2} S_2> y \lvert S_1> u}, \rho
\in (-1,1),\in R when u approaches the upper endpoint of F. On the density
function of \Theta we require a certain local asymptotic behaviour at 0,
whereas for F we require that it belongs to the Gumbel max-domain of
attraction. The main result of this contribution is an asymptotic expansion of
\Psi_{\rho,u}, which is then utilised to construct two estimators for the
conditional distribution function 1- \Psi_{\rho,u}. Further, we allow \Theta to
depend on u.


title: Variational Integrators for Almost-Integrable Systems

abstract:
  We construct several variational integrators--integrators based on a discrete
variational principle--for systems with Lagrangians of the form L = L_A +
epsilon L_B, with epsilon << 1, where L_A describes an integrable system. These
integrators exploit that epsilon << 1 to increase their accuracy by
constructing discrete Lagrangians based on the assumption that the integrator
trajectory is close to that of the integrable system. Several of the
integrators we present are equivalent to well-known symplectic integrators for
the equivalent perturbed Hamiltonian systems, but their construction and error
analysis is significantly simpler in the variational framework. One novel
method we present, involving a weighted time-averaging of the perturbing terms,
removes all errors from the integration at O(epsilon). This last method is
implicit, and involves evaluating a potentially expensive time-integral, but
for some systems and some error tolerances it can significantly outperform
traditional simulation methods.


title:
Surface texture and pulsation due to balloon bursting in different
  liquids

abstract:
  We study the instabilities occurring during the burst of an air balloon in a
liquid. These instabilities are typical for the deformation of an interface
between two fluids of different densities, similar to fingering in
Rayleigh-Taylor instability (see e.g. Sharp, 1984). In the Video a series of
bursts are shown for air balloons in different liquids. When the balloon tears
it tracks the surface, generating wrinkles and releasing the pressure inside.
Apparently, the texture of the surface during the burst becomes smoother as the
viscosity increases. During the burst the surface breaks and generates several
small bubbles. Furthermore, the pressure inside the balloon is higher than the
external pressure before the burst; once the balloon tears the pressure is
released and the generated bubbles pulsate several times (see e.g. Brennen,
1995). Such oscillations are more evident for higher internal pressures.


title:
Elliptic flow from final state interactions in the distorted-wave
  emission-function model

abstract:
  The effect of final state interactions on the elliptic flow coefficient
measured in relativistic heavy ion collisions is investigated within the DWEF
formalism established by Miller and Cramer [Phys. Rev. Lett. 94, 102302 (2005),
J. Phys. G34, 703 (2007), Phys. Rev. C78, 054905 (2008)]. It is found that the
optical potential previously found to give the best fit of particle
multiplicity and Hanbury Brown and Twiss radii in RHIC events has a moderate
effect on the resulting elliptic flow coefficient v_2. This indicates that
final state interactions should be taken into account to confidently predict
v_2 to better than ~20% accuracy.


title: Rodless Weissenberg effect

abstract:
  The climbing effect of a viscoelastic fluid when stirred by a spinning rod is
well documented and known as Weissenberg effect(Wei et al, 2006). This
phenomenon is related to the elasticity of the fluid. We have observed that
this effect can appear when the fluid is stirred without a rod. In this work, a
comparison of the flow around a spinning disk for a Newtonian and a
non-Newtonian liquids is presented. The flow is visualized with ink and small
bubbles as fluid path tracers. For a Newtonian fluid, at the center of the
spinning disk, the fluid velocity is directed towards the disk (sink flow); on
the other hand, for a viscoelatic liquid, a source flow is observed since the
fluid emerges from the disk. The toroidal vortices that appear on top of the
disk rotate in opposite directions for the Newtonian and non-Newtonian cases.
Similar observations have been reported for the classical rod climbing flow
(Siginer, 1984 and Escudier, 1984). Some authors have suggested that this flow
configuration can be used to determine the elastic properties of the liquid
(Escuider, 1984 and Joshep, 1973).


title:
The effective slip length and vortex formation in laminar flow over a
  rough surface

abstract:
  The flow of viscous incompressible fluid over a periodically corrugated
surface is investigated numerically by solving the Navier-Stokes equation with
the local slip and no-slip boundary conditions. We consider the effective slip
length which is defined with respect to the level of the mean height of the
surface roughness. With increasing corrugation amplitude the effective no-slip
boundary plane is shifted towards the bulk of the fluid, which implies a
negative effective slip length. The analysis of the wall shear stress indicates
that a flow circulation is developed in the grooves of the rough surface
provided that the local boundary condition is no-slip. By applying a local slip
boundary condition, the center of the vortex is displaced towards the bottom
the grooves and the effective slip length increases. When the intrinsic slip
length is larger than the corrugation amplitude, the flow streamlines near the
surface are deformed to follow the boundary curvature, the vortex vanishes, and
the effective slip length saturates to a constant value. Inertial effects
promote vortex flow formation in the grooves and reduce the effective slip
length.


title: Demonstration of a Plasmonic Dimple Lens for Nanoscale Focusing of Light

abstract:
  Focusing electromagnetic energy to sub-wavelength dimensions has become an
increasingly active field of research for a variety of applications such as
Heat Assisted Magnetic Recording (HAMR), nanolithography, and nanoscale optical
characterization of biological cells and single molecules using near-field
scanning optical microscopy (NSOM) technique. Double-sided surface plasmons in
a metal-insulator-metal (MIM) geometry have been shown to have very small
wavelengths for dielectric of thickness of less than 10 nm. A tapered
dielectric structure sandwiched between metal, can be used to efficiently
couple electromagnetic energy from free space photons to the plasmonic
wavelengths at the nanoscale. In this paper, we present the fabrication and
characterization of a novel MIM plasmonic lens structure.


title: Eigenvalue Separation in Some Random Matrix Models

abstract:
  The eigenvalue density for members of the Gaussian orthogonal and unitary
ensembles follows the Wigner semi-circle law. If the Gaussian entries are all
shifted by a constant amount c/Sqrt(2N), where N is the size of the matrix, in
the large N limit a single eigenvalue will separate from the support of the
Wigner semi-circle provided c > 1. In this study, using an asymptotic analysis
of the secular equation for the eigenvalue condition, we compare this effect to
analogous effects occurring in general variance Wishart matrices and matrices
from the shifted mean chiral ensemble. We undertake an analogous comparative
study of eigenvalue separation properties when the size of the matrices are
fixed and c goes to infinity, and higher rank analogues of this setting. This
is done using exact expressions for eigenvalue probability densities in terms
of generalized hypergeometric functions, and using the interpretation of the
latter as a Green function in the Dyson Brownian motion model. For the shifted
mean Gaussian unitary ensemble and its analogues an alternative approach is to
use exact expressions for the correlation functions in terms of classical
orthogonal polynomials and associated multiple generalizations. By using these
exact expressions to compute and plot the eigenvalue density, illustrations of
the various eigenvalue separation effects are obtained.


title: Noise Correlations in low-dimensional systems of ultracold atoms

abstract:
  We derive relations between standard order parameter correlations and the
noise correlations in time of flight images, which are valid for systems with
long range order as well as low dimensional systems with algebraic decay of
correlations. Both Bosonic and Fermionic systems are considered. For one
dimensional Fermi systems we show that the noise correlations are equally
sensitive to spin, charge and pairing correlations and may be used to
distinguish between fluctuations in the different channels. This is in contrast
to linear response experiments, such as Bragg spectroscopy, which are only
sensitive to fluctuations in the particle-hole channel (spin or charge). For
Bosonic systems we find a sharp peak in the noise correlation at opposite
momenta that signals pairing correlations in the depletion cloud. In a
condensate with true long range order, this peak is a delta function and we can
use Bogoliubov theory to study its temperature dependence. Interestingly we
find that it is enhanced with temperature in the low temperature limit. In one
dimensional condensates with only quasi-long range (i.e. power-law) order the
peak in the noise correlations also broadens to a power-law singularity.


title: Generic quantum walk using a coin-embedded shift operator

abstract:
  The study of quantum walk processes has been widely divided into two standard
variants, the discrete-time quantum walk (DTQW) and the continuous-time quantum
walk (CTQW). The connection between the two variants has been established by
considering the limiting value of the coin operation parameter in the DTQW, and
the coin degree of freedom was shown to be unnecessary [26]. But the coin
degree of freedom is an additional resource which can be exploited to control
the dynamics of the QW process. In this paper we present a generic quantum walk
model using a quantum coin-embedded unitary shift operation $U_{C}$. The
standard version of the DTQW and the CTQW can be conveniently retrieved from
this generic model, retaining the features of the coin degree of freedom in
both variants.


title:
Modified gravity as realistic candidate for dark energy, inflation and
  dark matter

abstract:
  We review the unification of early-time inflation with late-time acceleration
in several local modified gravity models which pass Solar System and
cosmological tests. It is also demonstrated that account of non-local
gravitational corrections to the action does not destroy the possibility of
such unification. Dark matter effect is caused by composite graviton degree of
freedom in such models.


title:
Correlation between doping induced disorder and superconducting
  properties in carbohydrate doped MgB2

abstract:
  A comprehensive study of the effects of carbohydrate doping on the
superconductivity of MgB2 has been conducted. In accordance with the dual
reaction model, more carbon substitution is achieved at lower sintering
temperature. As the sintering temperature is lowered, lattice disorder is
increased. Disorder is an important factor determining the transition
temperature for the samples studied in this work, as evidenced from the
correlations among the lattice strain, the resistivity and the transition
temperature. It is further shown that the increased critical current density in
the high field region can be understood by a recently-proposed percolation
model [Phys. Rev. Lett. 90 (2003) 247002]. For the critical current density
analysis, the upper critical field is estimated from a correlation that has
been reported in a recent review article [Supercond. Sci. Technol. 20 (2007)
R47], where a sharp increase in the upper critical field by doping is mainly
due to an increase in lattice disorder or impurity scattering. On the other
hand, it is shown that the observed reduction in self-field critical current
density is related to the reduction in the pinning force density by
carbohydrate doping.


title: Status of the QPACE Project

abstract:
  We give an overview of the QPACE project, which is pursuing the development
of a massively parallel, scalable supercomputer for LQCD. The machine is a
three-dimensional torus of identical processing nodes, based on the PowerXCell
8i processor. The nodes are connected by an FPGA-based, application-optimized
network processor attached to the PowerXCell 8i processor. We present a
performance analysis of lattice QCD codes on QPACE and corresponding hardware
benchmarks.


title:
CCD and photon-counting photometric observations of asteroids carried
  out at Padova and Catania observatories

abstract:
  We present the results of observational campaigns of asteroids performed at
Asiago Station of Padova Astronomical Observatory and at M.G. Fracastoro
Station of Catania Astrophysical Observatory, as part of the large research
programme on Solar System minor bodies undertaken since 1979 at the Physics and
Astronomy Department of Catania University. Photometric observations of six
Main-Belt asteroids (27 Euterpe, 173 Ino, 182 Elsa, 539 Pamina, 849 Ara, and
984 Gretia), one Hungaria (1727 Mette), and two Near-Earth Objects (3199
Nefertiti and 2004 UE) are reported. The first determination of the synodic
rotational period of 2004 UE was obtained. For 182 Elsa and 1727 Mette the
derived synodic period of 80.23+/-0.08 h and 2.981+/-0.001 h, respectively,
represents a significant improvement on the previously published values. For
182 Elsa the first determination of the H-G magnitude relation is also
presented.


title:
Two analytical formulae of the temperature inside a body by using
  partial lateral and initial data

abstract:
  This paper considerers the problem of computing the value of a solution of
the heat equation at a given point inside a bounded domain after the initial
time. It is assumed that the initial value of the solution inside the domain
(possibly in a part of the domain) is known; the boundary value and the normal
derivative on a part of the boundary of the domain over a finite time interval
are known. Two analytical formulae for the problem are given. Both formulae
make use of a special fundamental solution having a large parameter of the
backward heat equation.


title: Entropy and weak solutions in the LBGK model

abstract:
  In this paper, we derive entropy functions whose local equilibria are
suitable to recover the Euler-like equations in the framework of the Lattice
Boltzmann method. Numerical examples are also given, which are consistent with
the above theoretical arguments.


title: Holographic Superconductors

abstract:
  It has been shown that a gravitational dual to a superconductor can be
obtained by coupling anti-de Sitter gravity to a Maxwell field and charged
scalar. We review our earlier analysis of this theory and extend it in two
directions. First, we consider all values for the charge of the scalar field.
Away from the large charge limit, backreaction on the spacetime metric is
important. While the qualitative behaviour of the dual superconductor is found
to be similar for all charges, in the limit of arbitrarily small charge a new
type of black hole instability is found. We go on to add a perpendicular
magnetic field B and obtain the London equation and magnetic penetration depth.
We show that these holographic superconductors are Type II, i.e., starting in a
normal phase at large B and low temperatures, they develop superconducting
droplets as B is reduced.


title: Theory of the striped superconductor

abstract:
  We define a distinct phase of matter, a "pair density wave" (PDW), in which
the superconducting order parameter $\phi$ varies periodically as a function of
position such that when averaged over the center of mass position, all
components of $\phi$ vanish identically. Specifically, we study the simplest,
unidirectional PDW, the "striped superconductor," which we argue may be at the
heart of a number of spectacular experimental anomalies that have been observed
in the failed high temperature superconductor, La$_{2-x}$ Ba$_x$CuO$_4$. We
present a solvable microscopic model with strong electron-electron interactions
which supports a PDW groundstate. We also discuss, at the level of Landau
theory, the nature of the coupling between the PDW and other order parameters,
and the origins and some consequences of the unusual sensitivity of this state
to quenched disorder.


title: Capture of particles undergoing discrete random walks

abstract:
  It is shown that particles undergoing discrete-time jumps in 3D, starting at
a distance r0 from the center of an adsorbing sphere of radius R, are captured
with probability (R - c sigma)/r0 for r0 much greater than R, where c is
related to the Fourier transform of the scaled jump distribution and sigma is
the distribution's root-mean square jump length. For particles starting on the
surface of the sphere, the asymptotic survival probability is non-zero (in
contrast to the case of Brownian diffusion) and has a universal behavior
sigma/(R sqrt(6)) depending only upon sigma/R. These results have applications
to computer simulations of reaction and aggregation.


title: Curvature flow to Nirenberg problem

abstract:
  In this note, we study the curvature flow to Nirenberg problem on $S^2$ with
non-negative nonlinearity. This flow was introduced by Brendle and Struwe. Our
result is that the Nirenberg problems has a solution provided the prescribed
non-negative Gaussian curvature $f$ has its positive part, which possesses
non-degenerate critical points such that $\Delta_{S^2} f>0$ at the saddle
points.


title:
Charmonium dissociation temperatures in lattice QCD with a finite volume
  technique

abstract:
  Dissociation temperatures of J/\psi, \psi', and \chi_c states play key roles
in the sequential J/\psi suppression scenario for high energy heavy ion
collisions. We report on a study of charmonium dissociation temperatures in
quenched lattice QCD. On anisotropic lattices, we first subtract the effects of
the constant mode in finite temperature meson correlators, which have lead to
unphysical results in previous studies. We then extract ground and first exited
state masses by diagonalizing correlation functions among different source and
sink operators. To distinguish bound states from scattering states, we first
compare the charmonium mass spectra under different spatial boundary
conditions, and examine the shape and the volume-dependence of their
Bethe-Salpeter wave functions. From these studies, we found so far no sign of
scattering states up to about 2.3T_c.


title:
Effects of the chemomechanical stepping cycle on the traffic of
  molecular motors

abstract:
  We discuss effects of the stepping kinetics of molecular motors on their
traffic behavior on crowded filaments using a simple two-state chemomechanical
cycle. While the general traffic behavior is quite robust with respect to the
detailed kinetics of the step, a few observable parameters exhibit a strong
dependence on these parameters. Most strikingly, the effective unbinding rate
of the motors may both increase and decrease with increasing traffic density,
depending on the details of the motor step. Likewise the run length either
exhibits a strong decrease or almost no dependence on the traffic density. We
compare our theoretical results with recent experimental observations on motor
traffic.


title:
Infinite-randomness critical point in the two-dimensional disordered
  contact process

abstract:
  We study the nonequilibrium phase transition in the two-dimensional contact
process on a randomly diluted lattice by means of large-scale Monte-Carlo
simulations for times up to $10^{10}$ and system sizes up to $8000 \times 8000$
sites. Our data provide strong evidence for the transition being controlled by
an exotic infinite-randomness critical point with activated (exponential)
dynamical scaling. We calculate the critical exponents of the transition and
find them to be universal, i.e., independent of disorder strength. The
Griffiths region between the clean and the dirty critical points exhibits
power-law dynamical scaling with continuously varying exponents. We discuss the
generality of our findings and relate them to a broader theory of rare region
effects at phase transitions with quenched disorder. Our results are of
importance beyond absorbing state transitions because according to a
strong-disorder renormalization group analysis, our transition belongs to the
universality class of the two-dimensional random transverse-field Ising model.


title: Thermodynamics of SU(3) gauge theory at fixed lattice spacing

abstract:
  We study thermodynamics of SU(3) gauge theory at fixed scales on the lattice,
where we vary temperature by changing the temporal lattice size
N_t=(Ta_t)^{-1}. In the fixed scale approach, finite temperature simulations
are performed on common lattice spacings and spatial volumes. Consequently, we
can isolate thermal effects in observables from other uncertainties, such as
lattice artifact, renormalization factor, and spatial volume effect.
Furthermore, in the EOS calculations, the fixed scale approach is able to
reduce computational costs for zero temperature subtraction and parameter
search to find lines of constant physics, which are demanding in full QCD
simulations. As a test of the approach, we study the thermodynamics of the
SU(3) gauge theory on isotropic and anisotropic lattices. In addition to the
equation of state, we calculate the critical temperature and the static quark
free energy at a fixed scale.


title:
An Analytical Model of Information Dissemination for a Gossip-based
  Protocol

abstract:
  We develop an analytical model of information dissemination for a gossiping
protocol that combines both pull and push approaches. With this model we
analyse how fast an item is replicated through a network, and how fast the item
spreads in the network, and how fast the item covers the network. We also
determine the optimal size of the exchange buffer, to obtain fast replication.
Our results are confirmed by large-scale simulation experiments.


title:
The exact distribution of the sample variance from bounded continuous
  random variables

abstract:
  For a sample of absolutely bounded i.i.d. random variables with a continuous
density the cumulative distribution function of the sample variance is
represented by a univariate integral over a Fourier series. If the density is a
polynomial or a trigonometrical polynomial the coefficients of this series are
simple finite terms containing only the error function, the exponential
function and powers. In more general cases - e.g. for all beta densities - the
coefficients are given by some series expansions. The method is generalized to
positive semi-definite quadratic forms of bounded independent but not
necessarily identically distributed random variables if the form matrix differs
from a diagonal matrix D > 0 only by a matrix of rank 1


title:
Universal Monotonicity of Eigenvalue Moments and Sharp Lieb-Thirring
  Inequalities

abstract:
  We show that phase space bounds on the eigenvalues of Schr\"{o}dinger
operators can be derived from universal bounds recently obtained by E. M.
Harrell and the author via a monotonicity property with respect to coupling
constants. In particular, we provide a new proof of sharp Lieb-Thirring
inequalities.


title: Liouvillian Solutions of Difference-Differential Equations

abstract:
  For a field k$with an automorphism \sigma and a derivation \delta, we
introduce the notion of liouvillian solutions of linear difference-differential
systems {\sigma(Y) = AY, \delta(Y) = BY} over k and characterize the existence
of liouvillian solutions in terms of the Galois group of the systems. We will
give an algorithm to decide whether such a system has liouvillian solutions
when k = C(x,t), \sigma(x) = x+1, \delta = d/dt$ and the size of the system is
a prime.


title:
Time-dependent scattering theory for Schr\"odinger operators on
  scattering manifolds

abstract:
  We construct a time-dependent scattering theory for Schr\"odinger operators
on a manifold $M$ with asymptotically conic structure. We use the two-space
scattering theory formalism, and a reference operator on a space of the form
$R\times \partial M$, where $\partial M$ is the boundary of $M$ at infinity. We
prove the existence and the completeness of the wave operators, and show that
our scattering matrix is equivalent to the absolute scattering matrix, which is
defined in terms of the asymptotic expansion of generalized eigenfunctions. Our
method is functional analytic, and we use no microlocal analysis in this paper.


title: Simple reaction-diffusion population model on scale-free networks

abstract:
  We study a simple reaction-diffusion population model [proposed by A. Windus
and H. J. Jensen, J. Phys. A: Math. Theor. 40, 2287 (2007)] on scale-free
networks. In the case of fully random diffusion, the network topology cannot
affect the critical death rate, whereas the heterogeneous connectivity can
cause smaller steady population density and critical population density. In the
case of modified diffusion, we obtain a larger critical death rate and steady
population density, at the meanwhile, lower critical population density, which
is good for the survival of species. The results were obtained using a
mean-field-like framework and were confirmed by computer simulations.


title: Wave front set for solutions to perturbed harmonic oscillators

abstract:
  We consider Schr\"odinger equations with variable coefficients and the
harmonic potential. We suppose the perturbation is short-range type in the
sense of [Nakamura 2004]. We characterize the wave front set of the solutions
to the equation in terms of the classical scattering data and the propagator of
the unperturbed harmonic oscillator. In particular, we give a "recurrence of
singularities" type theorem for the propagation of the period $t=\pi$.


title: Galaxy clusters discovered with a Sunyaev-Zel'dovich effect survey

abstract:
  The South Pole Telescope (SPT) is conducting a Sunyaev-Zel'dovich (SZ) effect
survey over large areas of the southern sky, searching for massive galaxy
clusters to high redshift. In this preliminary study, we focus on a 40
square-degree area targeted by the Blanco Cosmology Survey (BCS), which is
centered roughly at right ascension 5h30m, declination -53 degrees. Over two
seasons of observations, this entire region has been mapped by the SPT at 95
GHz, 150 GHz, and 225 GHz. We report the four most significant SPT detections
of SZ clusters in this field, three of which were previously unknown and,
therefore, represent the first galaxy clusters discovered with an SZ survey.
The SZ clusters are detected as decrements with greater than 5-sigma
significance in the high-sensitivity 150 GHz SPT map. The SZ spectrum of these
sources is confirmed by detections of decrements at the corresponding locations
in the 95 GHz SPT map and non-detections at those locations in the 225 GHz SPT
map. Multiband optical images from the BCS survey demonstrate significant
concentrations of similarly colored galaxies at the positions of the SZ
detections. Photometric redshift estimates from the BCS data indicate that two
of the clusters lie at moderate redshift (z ~ 0.4) and two at high redshift (z
>~ 0.8). One of the SZ detections was previously identified as a galaxy cluster
using X-ray data from the ROSAT All-Sky Survey (RASS). Potential RASS
counterparts (not previously identified as clusters) are also found for two of
the new discoveries. These first four galaxy clusters are the most significant
SZ detections from a subset of the ongoing SPT survey. As such, they serve as a
demonstration that SZ surveys, and the SPT in particular, can be an effective
means for finding galaxy clusters.


title:
Influence of length on the noise delayed switching of long Josephson
  junctions

abstract:
  The transient dynamics of long overlap Josephson junctions in the frame of
the sine-Gordon model with a white noise source is investigated. The effect of
noise delayed decay is observed for the case of overdamped sine-Gordon
equation. It is shown that this noise induced effect, in the range of small
noise intensities, vanishes for junctions lengths greater than several
Josephson penetration length.


title:
Fundamental theorem of hyperbolic geometry without the injectivity
  assumption

abstract:
  Let $\mathbb{H}^n$ be the $n-$dimensional hyperbolic space. It is well known
that, if $f: \mathbb{H}^n\to \mathbb{H}^n$ is a bijection that preserves
$r-$dimensional hyperplanes, then $f$ is an isometry. In this paper we make
neither injectivity nor $r-$hyperplane preserving assumptions on $f$ and prove
the following result:
  Suppose that $f: \mathbb{H}^n\to \mathbb{H}^n$ is a surjective map and maps
an $r-$hyperplane into an $r-$hyperplane, then $f$ is an isometry. The
Euclidean version was obtained by A. Chubarev and I. Pinelis in 1999 among
other things. Our proof is essentially different from their and the similar
problem arising in the spherical case is open.


title: Powers of sequences and convergence of ergodic averages

abstract:
  A sequence $(s_n)$ of integers is good for the mean ergodic theorem if for
each invertible measure preserving system $(X,\mathcal{B},\mu,T)$ and any
bounded measurable function $f$, the averages $ \frac1N \sum_{n=1}^N
f(T^{s_n}x)$ converge in the $L^2$ norm. We construct a sequence $(s_n)$ that
is good for the mean ergodic theorem, but the sequence $(s_n^2)$ is not.
Furthermore, we show that for any set of bad exponents $B$, there is a sequence
$(s_n)$ where $(s_n^k)$ is good for the mean ergodic theorem exactly when $k$
is not in $B$. We then extend this result to multiple ergodic averages. We also
prove a similar result for pointwise convergence of single ergodic averages.


title: Noise effects in polymer dynamics

abstract:
  The study of the noise induced effects on the dynamics of a chain molecule
crossing a potential barrier, in the presence of a metastable state, is
presented. A two-dimensional stochastic version of the Rouse model for a
flexible polymer has been adopted to mimic the molecular dynamics and to take
into account the interactions between adjacent monomers. We obtain a
nonmonotonic behavior of the mean first passage time and its standard
deviation, of the polymer centre of inertia, with the noise intensity. These
findings reveal a noise induced effect on the mean crossing time. The role of
the polymer length is also investigated.


title:
One-loop effective action in ${\cal N}=2$ supersymmetric massive
  Yang-Mills theory

abstract:
  We consider the ${\cal N}=2$ supersymmetric theory of the massive Yang-Mills
field formulated in the ${\cal N}=2$ harmonic superspace. The various
gauge-invariant forms of writing the mass term in the action (in particular,
using the Stueckelberg superfield), which result in dual formulations of the
theory, are presented. We develop a gauge-invariant and explicitly
supersymmetric scheme of the loop off-shell expansion of the superfield
effective action. In the framework of this scheme, we calculate gauge-invariant
and explicitly ${\cal N}=2$ supersymmetric one-loop counterterms including new
counterterms depending on the Stueckelberg superfield. Component structure of
one of these counterterms is analyzed.


title:
Asymmetric scattering and non-orthogonal mode patterns in optical
  micro-spirals

abstract:
  Quasi-bound states in an open system do in general not form an orthogonal and
complete basis. It is, however, expected that the non-orthogonality is weak in
the case of well-confined states except close to a so-called exceptional point
in parameter space. We present numerical evidence showing that for passive
optical microspiral cavities the parameter regime where the non-orthogonality
is significant is rather broad. Here we observe almost-degenerate pairs of
well-confined modes which are highly non-orthogonal. Using a non-Hermitian
model Hamiltonian we demonstrate that this interesting phenomenon is related to
the asymmetric scattering between clockwise and counterclockwise propagating
waves in the spiral geometry. Numerical simulations of ray dynamics reveal a
clear ray-wave correspondence.


title: Hilltop Non-Gaussianity

abstract:
  We study non-Gaussianity induced by a pseudo Nambu-Goldstone boson with a
cosine-type scalar potential. We focus on how the non-Gaussianity is affected
when the pseudo Nambu-Goldstone boson rolls down from near the top of the
scalar potential where the deviation from a quadratic potential is large. We
find that the resultant non-Gaussianity is similar to that obtained in the
quadratic potential, if the pseudo Nambu-Goldstone boson accounts for the
curvature perturbation; the non-Gaussianity is enhanced, otherwise.


title:
Large-scale Dynamo Action Driven by Velocity Shear and Rotating
  Convection

abstract:
  By incorporating a large-scale shear flow into turbulent rotating convection,
we show that a sufficiently strong shear can promote dynamo action in flows
that in the absence of shear do not act as dynamos. Our results are consistent
with a dynamo driven by either the shear-current effect or by the interaction
between a fluctuating $\alpha$-effect and the velocity shear; they are though
inconsistent with either a classical $\alpha^2$ or $\alpha \omega$ mean field
dynamo.


title: Tip streaming from drops flowing in a spiral microchannel

abstract:
  This fluid dynamics video shows drops of water being transported by a mean
flow of oil, in a microchannel shaped as a logarithmic spiral. The channel
shape means that the drops are submitted to an increasing shear and elongation
as they flow nearer to the center of the spiral. A critical point is reached at
which a long singular tail is observed behind the drops, indicating that the
drops are accelerating. This is called "Tip streaming".


title:
Electrical rectification effect in single domain magnetic microstrips: a
  micromagnetics-based analysis

abstract:
  Upon passing an a.c. electrical current along magnetic micro- or nanostrips,
the measurement of a d.c. voltage that depends sensitively on current frequency
and applied field has been recently reported by A. Yamaguchi and coworkers. It
was attributed to the excitation of spin waves by the spin transfer torque,
leading to a time-varying anisotropic magnetoresistance and, by mixing of a.c.
current and resistance, to a d.c. voltage. We have performed a quantitative
analysis by micromagnetics, including the spin transfer torque terms considered
usually, of this situation. The signals found from the spin transfer torque
effect are several orders of magnitude below the experimental values, even if a
static inhomogeneity of magnetization (the so-called ripple) is taken into
account. On the other hand, the presence of a small non-zero average Oersted
field is shown to be consistent with the full set of experimental results, both
qualitatively and quantitatively. We examine, quantitatively, several sources
for this average field and point to the contacts to the sample as a likely
origin.


title: Selection Functions in Doppler Planet Searches

abstract:
  We present a preliminary analysis of the sensitivity of Anglo-Australian
Planet Search data to the orbital parameters of extrasolar planets. To do so,
we have developed new tools for the automatic analysis of large-scale
simulations of Doppler velocity planet search data. One of these tools is the
2-Dimensional Keplerian Lomb-Scargle periodogram, that enables the
straightforward detection of exoplanets with high eccentricities (something the
standard Lomb-Scargle periodogram routinely fails to do). We used this
technique to re-determine the orbital parameters of HD20782b, with one of the
highest known exoplanet eccentricities (e=0.97+/-0.01). We also derive a set of
detection criteria that do not depend on the distribution functions of fitted
Keplerian orbital parameters (which we show are non-Gaussian with pronounced,
extended wings). Using these tools, we examine the selection functions in
orbital period, eccentricity and planet mass of Anglo-Australian Planet Search
data for three planets with large-scale Monte Carlo-like simulations. We find
that the detectability of exoplanets declines at high eccentricities. However,
we also find that exoplanet detectability is a strong function of
epoch-to-epoch data quality, number of observations, and period sampling. This
strongly suggests that simple parametrisations of the detectability of
exoplanets based on "whole-of-survey" metrics may not be accurate. We have
derived empirical relationships between the uncertainty estimates for orbital
parameters that are derived from least-squares Keplerian fits to our
simulations, and the true 99% limits for the errors in those parameters, which
are larger than equivalent Gaussian limits by factors of 5-10. (abridged)


title:
Bound states of the Klein-Gordon equation for vector and scalar general
  Hulthen-type potentials in D-dimension

abstract:
  We solve the Klein-Gordon equation in any $D$-dimension for the scalar and
vector general Hulth\'{e}n-type potentials with any $l$ by using an
approximation scheme for the centrifugal potential. Nikiforov-Uvarov method is
used in the calculations. We obtain the bound state energy eigenvalues and the
corresponding eigenfunctions of spin-zero particles in terms of Jacobi
polynomials. The eigenfunctions are physical and the energy eigenvalues are in
good agreement with those results obtained by other methods for D=1 and 3
dimensions. Our results are valid for $q=1$ value when $l\neq 0$ and for any
$q$ value when $l=0$ and D=1 or 3. The $s$% -wave ($l=0$) binding energies for
a particle of rest mass $m_{0}=1$ are calculated for the three lower-lying
states $(n=0,1,2)$ using pure vector and pure scalar potentials.


title:
A Unified Monte Carlo Treatment of Gas-Grain Chemistry for Large
  Reaction Networks. I. Testing Validity of Rate Equations in Molecular Clouds

abstract:
  In this study we demonstrate for the first time that the unified Monte Carlo
approach can be applied to model gas-grain chemistry in large reaction
networks. Specifically, we build a time-dependent gas-grain chemical model of
the interstellar medium, involving about 6000 gas-phase and 200 grain surface
reactions. This model is used to test the validity of the standard and modified
rate equation methods in models of dense and translucent molecular clouds and
to specify under which conditions the use of the stochastic approach is
desirable.
  We found that at temperatures 25--30 K gas-phase abundances of H$_2$O,
NH$_3$, CO and many other gas-phase and surface species in the stochastic model
differ from those in the deterministic models by more than an order of
magnitude, at least, when tunneling is accounted for and/or diffusion energies
are 3x lower than the binding energies. In this case, surface reactions,
involving light species, proceed faster than accretion of the same species. In
contrast, in the model without tunneling and with high binding energies, when
the typical timescale of a surface recombination is greater than the timescale
of accretion onto the grain, we obtain almost perfect agreement between results
of Monte Carlo and deterministic calculations in the same temperature range. At
lower temperatures ($\sim10$ K) gaseous and, in particular, surface abundances
of most important molecules are not much affected by stochastic processes.


title: The Pleiades: the celestial herd of ancient timekeepers

abstract:
  In the ancient Egypt seven goddesses, represented by seven cows, composed the
celestial herd that provides the nourishment to her worshippers. This herd is
observed in the sky as a group of stars, the Pleiades, close to Aldebaran, the
main star in the Taurus constellation. For many ancient populations, Pleiades
were relevant stars and their rising was marked as a special time of the year.
In this paper, we will discuss the presence of these stars in ancient cultures.
Moreover, we will report some results of archeoastronomy on the role for
timekeeping of these stars, results which show that for hunter-gatherers at
Palaeolithic times, they were linked to the seasonal cycles of aurochs.


title:
Nonlinear Ramsey interferometry with the Rosen-Zener pulses on a
  two-component Bose-Einstein condensate

abstract:
  We propose a feasible scheme to realize nonlinear Ramsey interferometry with
a two-component Bose-Einstein condensate, where the nonlinearity arises from
the interaction between coherent atoms. In our scheme, two Rosen-Zener pulses
are separated by an intermediate holding period of variable duration and
through varying the holding period we have observed nice Ramsey interference
patterns in time domain. In contrast to the standard Ramsey fringes our
nonlinear Ramsey patterns display diversiform structures ascribed to the
interplay of the nonlinearity and asymmetry. In particular, we find that the
frequency of the nonlinear Ramsey fringes exactly reflects the strength of
nonlinearity as well as the asymmetry of system. Our finding suggests a
potential application of the nonlinear Ramsey interferometry in calibrating the
atomic parameters such as scattering length and energy spectrum.


title:
X-Ray Observation of Very High Energy Gamma-Ray Source, HESS J1745-303,
  with Suzaku

abstract:
  Suzaku observations of a TeV unidentified (unID) source, HESS J1745-303, are
presented. A possible excess of neutral iron line emission is discovered, and
is likely associated with the main part of HESS J1745-303, named "region A". It
may be an X-ray reflection nebula where the X-rays from previous Galactic
Center (GC) activity are reflected by a molecular cloud. This result further
strengthens the assumption that the molecular cloud which is spatially
coincident with region A of HESS J1745-303 is located in the GC region. The TeV
emission from molecular clouds is reminiscent of the diffuse TeV gamma-rays
from the GC giant molecular clouds, and it could have the same emission
mechanism. With deep exposure mapping observations by Suzaku, a tight
upper-limit on the 2-10 keV continuum diffuse emission from region A is
obtained, as 2.1x10^-13ergs s^-1cm^-2. The flux ratio between 1-10 TeV and 2-10
keV is larger than 4. Possible scenarios to reproduce wide-band spectra from
keV to TeV are examined. Thermal X-rays from nearby two old supernova remnants,
G359.0-0.9 and G359.1-0.5, are detected, and their emission properties are well
determined in the present study with deep exposure.


title:
Towards active microfluidics: Interface turbulence in thin liquid films
  with floating molecular machines

abstract:
  Thin liquid films with floating active protein machines are considered.
Cyclic mechanical motions within the machines, representing microscopic
swimmers, lead to molecular propulsion forces applied to the air-liquid
interface. We show that, when the rate of energy supply to the machines exceeds
a threshold, the flat interface becomes linearly unstable. As the result of
this instability, the regime of interface turbulence, characterized by
irregular traveling waves and propagating machine clusters, is established.
Numerical investigations of this nonlinear regime are performed. Conditions for
the experimental observation of the instability are discussed.


title: Magnetization plateaux in an extended Shastry-Sutherland model

abstract:
  We study an extended two-dimensional Shastry-Sutherland model in a magnetic
field where besides the usual Heisenberg exchanges of the Shastry-Sutherland
model two additional SU(2) invariant couplings are included. Perturbative
continous unitary transformations are used to determine the leading order
effects of the additional couplings on the pure hopping and on the long-range
interactions between the triplons which are the most relevant terms for small
magnetization. We then compare the energy of various magnetization plateaux in
the classical limit and we discuss the implications for the two-dimensional
quantum magnet SrCu$_2$(BO$_3$)$_2$.


title:
${\cal O}(\alpha\alpha_s)$ corrections to the $\gamma t\bar{t}$ vertex
  at the top quark threshold

abstract:
  We compute the last missing piece of the two-loop ${\cal O}(\alpha \alpha_s)$
corrections to $\gamma t \bar{t}$ vertex at the $t \bar{t}$ threshold due to
the exchange of a $W$ boson and a gluon. This contribution constitutes a
building block of the top quark threshold production cross section at electron
positron colliders.


title: The bound state problem of S-wave heavy quark meson-aitimeson systems

abstract:
  We investigated systematically whether the S-wave ($\bar{Q}q$) meson and the
($Q\bar{q}$) meson may form S-wave bound states in a chiral SU(3) quark model
by solving the resonating group method equation. Here $Q=c$ or $b$ and $q=u$,
$d$ or $s$. Our preliminary calculation disfavors the existence of $I=\frac12$
($\bar{Q}l$)-($Q\bar{s}$) molecules ($l=u,d$) while favors the existence of
isoscalar $B\bar{B}$, $B^*\bar{B}^*$ (J=2) and $B\bar{B}^*$ (C=+) molecules.
The existence of isovector (charm-anticharm) and (charm-bottom) molecules is
also disfavored. Therefore the resonance-like structure $Z^+(4051)$ is unlikely
to be an S-wave $D^*\bar{D}^*$ molecule.


title: On the computation of black hole entropy in loop quantum gravity

abstract:
  We discuss some issues related to the computation of black hole entropy in
loop quantum gravity from the novel point of view provided by the recent
number-theoretical methods introduced by the authors and their collaborators.
In particular we give exact expressions, in the form of integral transforms,
for the black hole entropy in terms of the area. We do this by following
several approaches based both on our combinatorial techniques and also on
functional equations similar to those employed by Meissner in his pioneering
work on this subject. To put our results in perspective we compare them with
those of Meissner. We will show how our methods confirm some of his findings,
extend the validity of others, and correct some mistakes. At the end of the
paper we will discuss the delicate issue of the asymptotics of black hole
entropy.


title: Abnormal diffusion of a single vortex in the two dimensional XY model

abstract:
  We study thermal diffusion dynamics of a single vortex in two dimensional XY
model. By numerical simulations we find an abnormal diffusion such that the
mobility decreases with time $t$ as $1/\ln t$. In addition we construct a one
dimensional diffusion-like equation to model the dynamics and confirm that it
conserves quantitative property of the abnormal diffusion. By analyzing the
reduced model, we find that the radius of the collectively moving region with
the vortex core grows as $R(t) \propto t^{1/2}$. This suggests that the
mobility of the vortex is described by dynamical correlation length as $1/\ln
R(t)$.


title: Liquid acrobatics

abstract:
  We experiment with injecting a continuous stream of gas into a shallow
liquid, similar to how one might blow into a straw placed at the bottom of a
near-empty drink. By varying the angle of the straw (here a metal needle), we
observe a variety of dynamics, which we film using a high-speed camera. Most
noteworthy is an intermediate regime in which cyclical jets erupt from the
air-liquid interface and breakup into air-born droplets. These droplets trace
out a parabolic trajectory and bounce on the air-liquid interface before
eventually coalescing. The shape of each jet, as well as the time between jets,
is remarkably similar and leads to droplets with nearly identical trajectories.
The following article accompanies the linked fluid dynamics video submitted to
the Gallery of Fluid Motion in 2008.


title:
Monte-Carlo simulation study of the two-stage percolation transition in
  enhanced binary trees

abstract:
  We perform Monte-Carlo simulations to study the Bernoulli ($p$) bond
percolation on the enhanced binary tree which belongs to the class of
nonamenable graphs with one end. Our numerical results show that the system has
two different percolation thresholds $p_{c1}$ and $p_{c2}$. All the points in
the intermediate phase $(p_{c1} < p < p_{c2})$ are critical and there exist
infinitely many infinite clusters in the intermediate phase. In this phase the
corresponding fractal exponent continuously increases with $p$ from zero to
unity.


title: Fibr\'es de Schwarzenberger et fibr\'es logarithmiques g\'en\'eralis\'es

abstract:
  We propose a generalization of logarithmic and Schwarzenberger bundles over
$\P^n=\P^n(\C)$ when the rank is greater than $n$. The first ones are
associated to finite sets of points on $\P^{n\vee}$ and the second ones to
curves with degree greater than $n$ on $\P^{n\vee}$. On the projective plane we
show that two logarithmic bundles are isomorphic if and only if they are
associated to the same set of points or if the two sets of points belong to a
curve of degree equal to the rank of the considered bundles.


title:
Hamilton Operator and the Semiclassical Limit for Scalar Particles in an
  Electromagnetic Field

abstract:
  We successively apply the generalized Case-Foldy-Feshbach-Villars (CFFV) and
the Foldy-Wouthuysen (FW) transformation to derive the Hamiltonian for
relativistic scalar particles in an electromagnetic field. In contrast to the
original transformation, the generalized CFFV transformation contains an
arbitrary parameter and can be performed for massless particles, which allows
solving the problem of massless particles in an electromagnetic field. We show
that the form of the Hamiltonian in the FW representation is independent of the
arbitrarily chosen parameter. Compared with the classical Hamiltonian for point
particles, this Hamiltonian contains quantum terms characterizing the
quadrupole coupling of moving particles to the electric field and the electric
and mixed polarizabilities. We obtain the quantum mechanical and semiclassical
equations of motion of massive and massless particles in an electromagnetic
field.


title: On the Origin of TeV Gamma-ray Emission from HESS J1834-087

abstract:
  We present an X-ray study of the field containing the extended TeV source
HESS J1834-087 using data obtained with the XMM-Newton telescope. Previously,
the coincidence of this source with both the shell-type supernova remnant (SNR)
W41 and a giant molecular cloud (GMC) was interpreted as favoring pi^0-decay
gamma-rays from interaction of the old SNR with the GMC. Alternatively, the TeV
emission has been attributed to inverse Compton scattering from leptons
deposited by PSR J1833-0827, a pulsar assumed to have been born in W41 but now
located 24' from the center of the SNR (and the TeV source). Instead, we argue
for a third possibility, that the TeV emission is powered by a previously
unknown pulsar wind nebula located near the center of W41. The candidate pulsar
is XMMU J183435.3-084443, a hard X-ray point source that lacks an optical
counterpart to R>21 and is coincident with diffuse X-ray emission. The X-rays
from both the point source and diffuse feature are evidently non-thermal and
highly absorbed. A best fit power-law model yields photon index Gamma ~ 0.2 and
Gamma ~ 1.9, for the point source and diffuse emission, respectively, and 2-10
keV flux ~ 5 X 10^(-13) ergs/cm^(2)/s for each. At the measured 4 kpc distance
of W41, the observed X-ray luminosity implies an energetic pulsar with Edot ~
10^(36)d_4^2 ergs/s, which is also sufficient to generate the observed
gamma-ray luminosity of 2.7 X 10^(34)d_4^2 ergs/s via inverse Compton
scattering.


title:
Backcalculation of the disease-age specific frequency of secondary
  transmission of primary pneumonic plague

abstract:
  Aim: To assess the frequency of secondary transmissions of primary pneumonic
plague relative to the onset of fever. Methods: A simple backcalculation method
was employed to estimate the frequency of secondary transmissions relative to
disease-age. A likelihood-based procedure was taken using observed
distributions of the serial interval (n = 177) and incubation period (n = 126).
Furthermore, an extended model was developed to account for the survival
probability of cases. Results: The simple backcalculation suggested that 31.0%
(95% confidence intervals (CI): 11.6, 50.4) and 28.0 % (95% CI: 10.2, 45.8) of
the total number of secondary transmissions had occurred at second and third
days of the disease, respectively, and more than four-fifths of the secondary
transmission occurred before the end of third day of disease. The
survivorship-adjusted frequency of secondary transmissions was obtained,
demonstrating that the infectiousness in later stages of illness was not
insignificant and indicates that the obtained frequencies were likely biased on
underlying factors including isolation measures. Conclusion: The simple
exercise suggests a need to implement countermeasures during pre-clinical stage
or immediately after onset. Further information is needed to elucidate the
finer details of the disease-age specific infectiousness.


title: Mottness underpins the anomalous optical response of Iron Pnictides

abstract:
  The recent discovery of high-temperature superconductivity (HTSC) in doped
Iron pnictides is the latest example of unanticipated behavior exhibited by
$d$- and $f$-band materials. The symmetry of the SC gap, along with the
mechanism of its emergence from the ``normal'' state is a central issue in this
context. Here, motivated by a host of experimental signatures suggesting strong
correlations in the Fe-pnictides, we undertake a detailed study of their normal
state. Focussing on symmetry-unbroken phases, we use the correlated band
structure method, LDA+DMFT, to study the one-particle responses of both ${\rm
LaO_{1-x}FeAsF_{x}}$ and ${\rm SmO_{1-x}FeAsF_{x}}$ in detail. Basing ourselves
on excellent quantitative agreement between LDA+DMFT and key experiments
probing the one-particle responses, we extend our study, undertaking the first
detailed study of their normal state electrodynamic response. In particular, we
propose that near-total normal state incoherence, resulting from strong, {\it
local} correlations in the Fe $d$-shell in Fe-pnictides, underpins the
incoherent normal state transport found in these materials, and discuss the
specific electronic mechanisms leading to such behavior. We also discuss the
implications of our work for the multi-band nature of the SC by studying the
pairing ``glue'' function, which we find to be an overdamped, electronic
continuum. Similarities and differences between cuprates and Fe-pnictides are
also touched upon. Our study supports the view that SC in Fe-pnictides arises
from a bad metallic, incoherent ``normal'' state that is proximate to a Mott
insulator.


title:
Fluctuation-Dissipation relation in sub-diffusive systems: the case of
  granular single-file

abstract:
  We study a gas of hard rods on a ring, driven by an external thermostat, with
either elastic or inelastic collisions, which exhibits sub-diffusive behavior
$<x^2 > \sim t^{1/2}$. We show the validity of the usual
Fluctuation-Dissipation (FD) relation, i.e. the proportionality between the
response function and the correlation function, when the gas is elastic or
diluted. On the contrary, in strongly inelastic or dense cases, when the tracer
velocity is no more independent of the other degrees of freedom, the Einstein
formula fails and must be replaced by a more general FD relation.


title: Can opacity changes help to reproduce the hybrid star pulsations?

abstract:
  Hybrid stars like Nu Eridani and 12 Lacertae show two different types of
pulsations: (i) low-order acoustic and gravity modes of the Beta Cephei type
with periods of about 3-6 hours, and (ii) high-order gravity modes of the SPB
type with periods of about 1.5-3 days. Theoretical computations using both OPAL
and OP opacity data well reproduce short period low-order pulsations of the
Beta Cep type and show a tendency to instability of high-order gravity modes,
especially for stellar models built with the OP opacities. However, instability
at observed long periods has not been achieved. We test effects of artificial
opacity modifications in the deep envelope on the instability of some hybrid
star models. For Nu Eri models, an opacity increase both in the Z opacity bump
region at temperature of about 200 000 K and in the region of the deeper
opacity bump at temperature of about 2-2.5 million degrees (this bump is also
mainly due to excited ions of the iron-group elements) may result in
instability of the high-order gravity modes with the observed periods. The
shortest observed period of 3 hours can also be excited in modified models.
However, the required opacity increase seems to be quite large (up to 2 times
in some stellar layers) which may be incompatible with atomic physics.


title: The glasma initial state and JIMWLK factorization

abstract:
  We review recent work on understanding the next to leading order corrections
to the classical fields that dominate the initial stages of a heavy ion
collision. We have recently shown that the leading ln(1/x) divergences of these
corrections to gluon multiplicities can be factorized into the JIMWLK evolution
of the color charge density distributions.


title: Stabilizing single atom contacts by molecular bridge formation

abstract:
  Gold-molecule-gold junctions can be formed by carefully breaking a gold wire
in a solution containing dithiolated molecules. Surprisingly, there is little
understanding on the mechanical details of the bridge formation process and
specifically on the role that the dithiol molecules play themselves. We propose
that alkanedithiol molecules have already formed bridges between the gold
electrodes before the atomic gold-gold junction is broken. This leads to
stabilization of the single atomic gold junction, as observed experimentally.
Our data can be understood within a simple spring model.


title: A strict lower-limit EBL: Applications on gamma-ray absorption

abstract:
  A strict lower limit flux for the extragalactic background light from
ultraviolet to the far-infrared photon energies is presented. The spectral
energy distribution is derived using an established EBL model based on galaxy
formation. The model parameters are chosen to fit the lower limit data from
number count observations in particular recent results by the SPITZER infrared
space telescope. A lower limit EBL model is needed to calculate guaranteed
absorption due to pair production in extragalactic gamma-ray sources as in TeV
blazars.


title:
Supersymmetric renormalisation of the CKM matrix and new constraints on
  the squark mass matrices

abstract:
  We compute the finite renormalisation of the Cabibbo-Kobayashi-Maskawa (CKM)
matrix induced by gluino-squark diagrams in the MSSM with non-minimal sources
of flavour violation. Subsequently we derive bounds on the flavour-off-diagonal
elements of the squark mass matrices by requiring that the radiative
corrections to the CKM elements do not exceed the experimental values. Our
constraints on the associated dimensionless quantities delta^{d LR}_{ij}, j>i,
are stronger than the bounds from flavour-changing neutral current (FCNC)
processes if gluino and squarks are heavier than 500 GeV. Our bound on
|delta^{u LR}_{12}| is stronger than the FCNC bound from D-D-bar mixing for
superpartner masses above 900 GeV. We further find a useful bound on
|delta_{13}^{u LR}|, for which no FCNC constraint is known. Our results imply
that it is still possible to generate all observed flavour violation from the
soft supersymmetry-breaking terms without conflicting with present-day data on
FCNC processes. We suggest that a flavour symmetry renders the Yukawa sector
flavour-diagonal and the trilinear supersymmetry-breaking terms are the spurion
fields breaking this flavour symmetry. We further derive the dominant
supersymmetric radiative corrections to the couplings of charged Higgs bosons
and charginos to quarks and squarks.


title:
Abelianisation of orthogonal groups and the fundamental group of modular
  varieties

abstract:
  We study the commutator subgroup of integral orthogonal groups belonging to
indefinite quadratic forms. We show that the index of this commutator is 2 for
many groups that occur in the construction of moduli spaces in algebraic
geometry, in particular the moduli of K3 surfaces. We give applications to
modular forms and to computing the fundamental groups of some moduli spaces.


title: Quantum Bounds on Bell inequalities

abstract:
  We have determined the maximum quantum violation of 241 tight bipartite Bell
inequalities with up to five two-outcome measurement settings per party by
constructing the appropriate measurement operators in up to six-dimensional
complex and eight-dimensional real component Hilbert spaces using numerical
optimization. Out of these inequalities 129 has been introduced here. In 43
cases higher dimensional component spaces gave larger violation than qubits,
and in 3 occasions the maximum was achieved with six-dimensional spaces. We
have also calculated upper bounds on these Bell inequalities using a method
proposed recently. For all but 20 inequalities the best solution found matched
the upper bound. Surprisingly, the simplest inequality of the set examined,
with only three measurement settings per party, was not among them, despite the
high dimensionality of the Hilbert space considered. We also computed detection
threshold efficiencies for the maximally entangled qubit pair. These could be
lowered in several instances if degenerate measurements were also allowed.


title: Heavy Flavor Physics through e-Science

abstract:
  Heavy flavor physics is an important element in understanding the nature of
physics. The accurate knowledge of properties of heavy flavor physics plays an
essential role for the determination of the Cabibbo-Kobayashi-Maskawa (CKM)
matrix. Asymmetric-energy e+e- B factories (BaBar and Belle) run their
operation and will upgrade B factories to become super Belle. The size of
available B meson samples will be dramatically increased. Also the data size of
Tevatron experiments (CDF, D0) are on the order of PetaByte. Therefore we use
new concept of e-Science for heavy flavor physics. This concept is about
studying heavy flavor physics anytime and anywhere even if we are not on-site
of accelerator laboratories and data size is immense. The component of this
concept is data production, data processing and data analysis anytime and
anywhere. We apply this concept to current CDF experiment at Tevatron. We will
expand this concept to Super Belle and LHC (Large Hadron Collider) experiments
which will achieve an accuracy of measurements in the next decades.


title: Magnetogenesis and the primordial non-gaussianity

abstract:
  The primordial density fluctuation inevitably couples to all forms of matter
via loop corrections and depends on the ambient conditions while inflation was
ongoing. This gives us an opportunity to observe processes which were in
progress while the universe was inflating, provided they were sufficiently
dramatic to overcome suppression by powers of (H/MP)^2 ~ 10^(-9), where H is
the Hubble scale during inflation and MP is the Planck mass. As an example, if
a primordial magnetic field was synthesized during inflation, as suggested by
some interpretations of the apparently universal 10^(-6) gauss field observed
on galactic scales, then this could leave traces in inflationary observables.
In this paper, I compute corrections to the spectrum and bispectrum generated
by a varying electromagnetic coupling during inflation, assuming that the
variation in this coupling is mediated by interaction with a collection of
light scalar fields. If the mass scale associated with this interaction is too
far below the Planck scale then the stability of perturbation theory can be
upset. For the mass-scale which is relevant in the standard magnetogenesis
scenario, however, the theory is stable and the model is apparently consistent
with observational constraints.


title: Stability of additive-free water-in-oil emulsions

abstract:
  We calculate ion distributions near a planar oil-water interface within
non-linear Poisson-Boltzmann theory, taking into account the Born self-energy
of the ions in the two media. For unequal self-energies of cations and anions,
a spontaneous charge separation is found such that the water and oil phase
become oppositely charged, in slabs with a typical thickness of the Debye
screening length in the two media. From the analytical solutions, the
corresponding interfacial charge density and the contribution to the
interfacial tension is derived, together with an estimate for the
Yukawa-potential between two spherical water droplets in oil. The parameter
regime is explored where the plasma coupling parameter exceeds the
crystallization threshold, i.e. where the droplets are expected to form
crystalline structures due to a strong Yukawa repulsion, as recently observed
experimentally. Extensions of the theory that we discuss briefly include
numerical calculations on spherical water droplets in oil, and analytical
calculations of the linear PB-equation for a finite oil-water interfacial
width.


title: Towards a Better Understanding of the Semigroup Tree

abstract:
  In this paper we elaborate on the structure of the semigroup tree and the
regularities on the number of descendants of each node observed earlier. These
regularites admit two different types of behavior and in this work we
investigate which of the two types takes place in particular for well-known
classes of semigroups. Also we study the question of what kind of chains appear
in the tree and characterize the properties (like being (in)finite) thereof. We
conclude with some thoughts that show how this study of the semigroup tree may
help in solving the conjecture of Fibonacci-like behavior of the number of
semigroups with given genus.


title:
Reflection, Transmission and Trapping Dynamics of Lattice Solitons at
  Interfaces

abstract:
  Surface soliton formation and lattice soliton dynamics at an interface
between two inhomogeneous periodic media are studied in terms of an effective
particle approach. The global reflection, transmission and trapping
characteristics are obtained in direct analogy to linear Snell's laws for
homogeneous media. Interesting dynamics related to soliton power-dependent
formation of potential barriers and wells suggest spatial filtering
functionality of the respective structures.


title: Drinfel'd doubles and Shapovalov determinants

abstract:
  The Shapovalov determinant for a class of pointed Hopf algebras is
calculated, including quantized enveloping algebras, Lusztig's small quantum
groups, and quantized Lie superalgebras. Our main tools are root systems, Weyl
groupoids, and Lusztig type isomorphisms. We elaborate powerful novel
techniques for the algebras at roots of unity, and pass to the general case
using a density argument.
  Key words: Hopf algebra, Nichols algebra, quantum group, representation


title: Microburst windspeed potential assessment: progress and developments

abstract:
  A suite of products has been developed and evaluated to assess hazards
presented by convective downbursts to aircraft in flight derived from the
current generation of GOES. The existing suite of GOES microburst products
employs the sounder to calculate risk based on conceptual models of favorable
environmental profiles for convective downburst generation. Accordingly, a
diagnostic nowcasting product, the Microburst Windspeed Potential Index, is
designed to infer attributes of a favorable microburst environment. In
addition, a GOES-West imager microburst algorithm that employs brightness
temperature differences between band 3 (upper level water vapor), band 4
(longwave infrared window), and split window band 5 has been developed to
supplement the sounder-derived products. This paper provides an updated
assessment of the sounder MWPI and imager microburst algorithms, presents case
studies demonstrating effective operational use of the microburst products, and
presents validation results for the 2008 convective season over United States
Great Plains and Great Basin regions.