title: A dispersive approach to Sudakov resummation

abstract:
  We present a general all-order formulation of Sudakov resummation in QCD in
terms of dispersion integrals. We show that the Sudakov exponent can be written
as a dispersion integral over spectral density functions, weighted by
characteristic functions that encode information on power corrections. The
characteristic functions are defined and computed analytically in the
large-beta_0 limit. The spectral density functions encapsulate the non-Abelian
nature of the interaction. They are defined by the time-like discontinuity of
specific effective charges (couplings) that are directly related to the
familiar Sudakov anomalous dimensions and can be computed order-by-order in
perturbation theory. The dispersive approach provides a realization of Dressed
Gluon Exponentiation, where Sudakov resummation is enhanced by an internal
resummation of running-coupling corrections. We establish all-order relations
between the scheme-invariant Borel formulation and the dispersive one, and
address the difference in the treatment of power corrections. We find that in
the context of Sudakov resummation the infrared-finite-coupling hypothesis is
of special interest because the relevant coupling can be uniquely identified to
any order, and may have an infrared fixed point already at the perturbative
level. We prove that this infrared limit is universal: it is determined by the
cusp anomalous dimension. To illustrate the formalism we discuss a few examples
including B-meson decay spectra, deep inelastic structure functions and
Drell-Yan or Higgs production.


title:
Singular limits for the bi-laplacian operator with exponential
  nonlinearity in $\R^4$

abstract:
  Let $\Omega$ be a bounded smooth domain in $\mathbb{R}^{4}$ such that for
some integer $d\geq1$ its $d$-th singular cohomology group with coefficients in
some field is not zero, then problem
  {\Delta^{2}u-\rho^{4}k(x)e^{u}=0 & \hbox{in}\Omega,
  u=\Delta u=0 & \hbox{on}\partial\Omega,
  has a solution blowing-up, as $\rho\to0$, at $m$ points of $\Omega$, for any
given number $m$.


title:
Design Considerations for a Ground-based Transit Search for Habitable
  Planets Orbiting M dwarfs

abstract:
  By targeting nearby M dwarfs, a transit search using modest equipment is
capable of discovering planets as small as 2 Earth radii in the habitable zones
of their host stars. The MEarth Project, a future transit search, aims to
employ a network of ground-based robotic telescopes to monitor M dwarfs in the
northern hemisphere with sufficient precision and cadence to detect such
planets. Here we investigate the design requirements for the MEarth Project. We
evaluate the optimal bandpass, and the necessary field of view, telescope
aperture, and telescope time allocation on a star-by-star basis, as is possible
for the well-characterized nearby M dwarfs. Through these considerations, 1,976
late M dwarfs (R < 0.33 Rsun) emerge as favorable targets for transit
monitoring. Based on an observational cadence and on total telescope time
allocation tailored to recover 90% of transit signals from planets in habitable
zone orbits, we find that a network of ten 30 cm telescopes could survey these
1,976 M dwarfs in less than 3 years. A null result from this survey would set
an upper limit (at 99% confidence) of 17% for the rate of occurrence of planets
larger than 2 Earth radii in the habitable zones of late M dwarfs, and even
stronger constraints for planets lying closer than the habitable zone. If the
true occurrence rate of habitable planets is 10%, the expected yield would be
2.6 planets.


title:
Freshly Formed Dust in the Cassiopeia A Supernova Remnant as Revealed by
  the Spitzer Space Telescope

abstract:
  We performed Spitzer Infrared Spectrograph mapping observations covering
nearly the entire extent of the Cassiopeia A supernova remnant (SNR), producing
mid-infrared (5.5-35 micron) spectra every 5-10". Gas lines of Ar, Ne, O, Si, S
and Fe, and dust continua were strong for most positions. We identify three
distinct ejecta dust populations based on their continuum shapes. The dominant
dust continuum shape exhibits a strong peak at 21 micron. A line-free map of 21
micron-peak dust made from the 19-23 micron range closely resembles the [Ar
II], [O IV], and [Ne II] ejecta-line maps implying that dust is freshly formed
in the ejecta. Spectral fitting implies the presence of SiO2, Mg
protosilicates, and FeO grains in these regions. The second dust type exhibits
a rising continuum up to 21 micron and then flattens thereafter. This ``weak 21
micron'' dust is likely composed of Al2O3 and C grains. The third dust
continuum shape is featureless with a gently rising spectrum and is likely
composed of MgSiO3 and either Al2O3 or Fe grains. Using the least massive
composition for each of the three dust classes yields a total mass of 0.02
Msun. Using the most-massive composition yields a total mass of 0.054 Msun. The
primary uncertainty in the total dust mass stems from the selection of the dust
composition necessary for fitting the featureless dust as well as 70 micron
flux. The freshly formed dust mass derived from Cas A is sufficient from SNe to
explain the lower limit on the dust masses in high redshift galaxies.


title: Automating dipole subtraction for QCD NLO calculations

abstract:
  In this publication the construction of an automatic algorithm to subtract
infrared divergences in real QCD corrections through the Catani-Seymour dipole
subtraction method [arXiv:hep-ph/9605323] is reported. The resulting computer
code has been implemented in the matrix element generator AMEGIC++
[arXiv:hep-ph/0109036]. This will allow for the automatic generation of dipole
subtraction terms and their integrals over the one-parton emission phase space
for any given process. If the virtual matrix element is provided as well, this
then directly leads to an NLO QCD parton level event generator.


title: A Generalization of a Result of Hardy and Littlewood

abstract:
  In this note we study the growth of \sum_{m=1}^M\frac1{\|m\alpha\|} as a
function of M for different classes of \alpha\in[0,1). Hardy and Littlewood
showed that for numbers of bounded type, the sum is \simeq M\log M. We give a
very simple proof for it. Further we show the following for generic \alpha. For
a non-decreasing function \phi tending to infinity,
\limsup_{M\to\infty}\frac1{\phi(\log M)}\bigg[\frac1{M\log
M}\sum_{m=1}^M\frac1{\|m\alpha\|}\bigg] is zero or infinity according as
\sum\frac1{k\phi(k)} converges or diverges.


title: Hyperbolicity of general deformations

abstract:
  We present two methods of constructing low degree Kobayashi hyperbolic
hypersurfaces in the projective space: the projection method and the
deformation method. The talk is based on joint works of the speaker with B.
Shiffman and C. Ciliberto.


title: Nonperturbative Heavy-Quark Diffusion in the Quark-Gluon Plasma

abstract:
  We evaluate heavy-quark (HQ) transport properties in a Quark-Gluon Plasma
(QGP) employing interaction potentials extracted from thermal lattice QCD.
Within a Brueckner many-body scheme we calculate in-medium T-matrices for
charm- and bottom-quark scattering off light quarks in the QGP. The
interactions are dominated by attractive meson and diquark channels which
support bound and resonance states up to temperatures of ~1.5 T_c. We apply
pertinent drag and diffusion coefficients (supplemented by perturbative
scattering off gluons) in Langevin simulations in an expanding fireball to
compute HQ spectra and elliptic flow in \sqrt{s_{NN}}=200 GeV Au-Au collisions.
We find good agreement with semileptonic electron-decay spectra which supports
our nonperturbative computation of the HQ diffusion coefficient, suggestive for
a strongly coupled QGP.


title: Lattice effects and current reversal in superconducting ratchets

abstract:
  Competition between the vortex lattice and a lattice of asymmetric artificial
defects is shown to play a crucial role in ratchet experiments in
superconducting films. We present a novel and collective mechanism for current
reversal based on a reconfiguration of the vortex lattice. In contrast to
previous models of vortex current reversal, the mechanism is based on the
global response of the vortex lattice to external forces.


title: Magnetic processes in a collapsing dense core. I Accretion and Ejection

abstract:
  Abridged. It is important for the star formation process to understand the
collapse of a prestellar dense core. We investigate the effect of the magnetic
field during the first collapse up to the formation of the firstcore, focusing
particularly on the magnetic braking and the launching of outflows. We perform
3D AMR high resolution numerical simulations of a magnetically supercritical
collapsing dense core using the RAMSES MHD code and develop semi-analytical
models that we compare with the numerical results. We study in detail the
various profiles within the envelope of the collapsing core for various
magnetic field strengths. Even modest values of magnetic field strength modify
the collapse significantly. This is largely due to the amplification of the
radial and toroidal components of the magnetic field by the differential
motions within the collapsing core. For a weak magnetic intensity corresponding
to an initial mass-to-flux over critical mass-to-flux ratio, $\mu$ equals to
20, a centrifugally supported disk forms. The strong differential rotation
triggers the growth of a slowly expanding magnetic tower. For a higher magnetic
field strengths corresponding to $\mu=2$, the collapse occurs primarily along
the field lines, therefore delivering weaker angular momentum in the inner part
whereas at the same time, strong magnetic braking occurs. As a consequence no
centrifugally supported disk forms. An outflow is launched from the central
thermally supported core. Detailed comparisons with existing analytical
predictions indicate that it is magneto-centrifugally driven. For cores having
a mass-to-flux over critical mass-to-flux radio $\mu < 5$, the magnetic field
appears to have a significant impact.....


title:
Magnetic processes in a collapsing dense core. II Fragmentation. Is
  there a fragmentation crisis ?

abstract:
  Abridged. A large fraction of stars are found in binary systems. It is
therefore important for our understanding of the star formation process, to
investigate the fragmentation of dense molecular cores. We study the influence
of the magnetic field, ideally coupled to the gas, on the fragmentation in
multiple systems of collapsing cores. We present high resolution numerical
simulations performed with the RAMSES MHD code starting with a uniform sphere
in solid body rotation and a uniform magnetic field parallel to the rotation
axis. We pay particular attention to the strength of the magnetic field and
interpret the results using the analysis presented in a companion paper. The
results depend much on the amplitude, $A$, of the perturbations seeded
initially. For a low amplitude, $A=0.1$, we find that for values of the
mass-to-flux over critical mass-to-flux ratio, $\mu$, as high as $\mu = 20$,
the centrifugally supported disk which fragments in the hydrodynamical case, is
stabilized and remains axisymmetric. Detailed investigations reveals that this
is due to the rapid growth of the toroidal magnetic field induced by the
differential motions within the disk. For values of $\mu$ smaller $\simeq 5$,
corresponding to larger magnetic intensities, there is no centrifugally
supported disk because of magnetic braking. When the amplitude of the
perturbation is equal to $A=0.5$, each initial peak develops independently and
the core fragments for a large range of $\mu$. Only for values of $\mu$ close
to 1 is the magnetic field able to prevent the fragmentation. Since a large
fraction of stars are binaries, the results of low magnetic intensities
preventing the fragmentation in case of weak perturbations, is problematic. We
discuss three possible mechanisms...


title: Fluctuations around the Tachyon Vacuum in Open String Field Theory

abstract:
  We consider quadratic fluctuations around the tachyon vacuum numerically in
open string field theory. We work on a space ${\cal H}_N^{{\rm vac}}$ spanned
by basis string states used in the Schnabl's vacuum solution. We show that the
truncated form of the Schnabl's vacuum solution on ${\cal H}_N^{{\rm vac}}$ is
well-behaved in numerical work. The orthogonal basis for the new BRST operator
$\tilde Q$ on ${\cal H}_N^{{\rm vac}}$ and the quadratic forms of potentials
for independent fields around the vacuum are obtained. Our numerical results
support that the Schnabl's vacuum solution represents the minimum energy
solution for arbitrary fluctuations also in open string field theory.


title: The complete lowest order chiral Lagrangian from a little box

abstract:
  We recently performed a pilot study determining the parameters of the leading
order chiral Lagrangian from distributions of the eigenvalues of a quenched
Dirac operator coupled to an imaginary isospin chemical potential. We
complement a quick survey of our recent preprint arXiv:0708.1731 [hep-lat] by
addressing some points raised during discussions at the conference.


title: Using invariants for phylogenetic tree construction

abstract:
  Phylogenetic invariants are certain polynomials in the joint probability
distribution of a Markov model on a phylogenetic tree. Such polynomials are of
theoretical interest in the field of algebraic statistics and they are also of
practical interest--they can be used to construct phylogenetic trees. This
paper is a self-contained introduction to the algebraic, statistical, and
computational challenges involved in the practical use of phylogenetic
invariants. We survey the relevant literature and provide some partial answers
and many open problems.


title: The group reduction for bounded cosine functions on UMD spaces

abstract:
  It is shown that if A generates a bounded cosine operator function on a UMD
space X, then i(-A)^{1/2} generates a bounded C_0-group. The proof uses a
transference principle for cosine functions.


title:
The Orbital Period of the Wolf-Rayet Binary IC 10 X-1; Dynamic Evidence
  that the Compact Object is a Black Hole

abstract:
  IC 10 X-1 is a bright (Lx=10^38 ergs/s) variable X-ray source in the local
group starburst galaxy IC 10. The most plausible optical counterpart is a
luminous Wolf-Rayet star, making IC 10 X-1 a rare example of a Wolf-Rayet X-ray
binary. In this paper, we report on the detection of an X-ray orbital period
for IC 10 X-1of 34.4 hours. This result, combined with a re-examination of
optical spectra, allow us to determine a mass function for the system f(m)=7.8
Msun and a probable mass for the compact object of 24-36 Msun. If this analysis
is correct, the compact object is the most massive known stellar black black
hole. We further show that the observed period is inconsistent with Roche lobe
overflow, suggesting that the binary is detached and the black hole is
accreting the wind of the Wolf-Rayet star. The observed mass loss rate of
[MAC92] 17-A is sufficient to power the X-ray luminosity of IC 10 X-1.


title: Selection principles and countable dimension

abstract:
  We characterize countable dimensionality and strong countable dimensionality
by means of an infinite game.


title: Baryonic branches and resolutions of Ricci-flat Kahler cones

abstract:
  We consider deformations of N=1 superconformal field theories that are
AdS/CFT dual to Type IIB string theory on Sasaki-Einstein manifolds,
characterised by non-zero vacuum expectation values for certain baryonic
operators. Such baryonic branches are constructed from (partially) resolved,
asymptotically conical Ricci-flat Kahler manifolds, together with a choice of
point where the stack of D3-branes is placed. The complete solution then
describes a renormalisation group flow between two AdS fixed points. We discuss
the use of probe Euclidean D3-branes in these backgrounds as a means to compute
expectation values of baryonic operators. The Y^{p,q} theories are used as
illustrative examples throughout the paper. In particular, we present
supergravity solutions describing flows from the Y^{p,q} theories to various
different orbifold field theories in the infra-red, and successfully match this
to an explicit field theory analysis.


title: Products and selection principles

abstract:
  The product of a Sierpinski set and a Lusin set has Menger's property. The
product of a gamma set and a Lusin set has Rothberger's property.


title:
Effect of the acrylic acid content on the permeability and water uptake
  of latex films

abstract:
  Acrylic acid (AA) is a monomer commonly employed in emulsion polymerization
to provide electrostatic colloidal stability and improve specific film
performance. The addition of AA not only modifies the kinetics of the
polymerization, but also it takes part in the interaction between colloidal
particles, which has a strong influence on their packing and consequent latex
film properties. In this contribution a theoretical modeling of the latex film
formation is presented and compared to experimental results: water vapor
permeability and latex film capacitance are studied as a function of AA
content. It has been shown that water uptake is mainly affected by film
morphology which in turn is defined by intercolloidal interaction and drying
rate.


title: Local and Nonlocal Dispersive Turbulence

abstract:
  We consider the evolution of a family of 2D dispersive turbulence models. The
members of this family involve the nonlinear advection of a dynamically active
scalar field, the locality of the streamfunction-scalar relation is denoted by
$\alpha$, with smaller $\alpha$ implying increased locality. The dispersive
nature arises via a linear term whose strength is characterized by a parameter
$\epsilon$. Setting $0 < \epsilon \le 1$, we investigate the interplay of
advection and dispersion for differing degrees of locality. Specifically, we
study the forward (inverse) transfer of enstrophy (energy) under large-scale
(small-scale) random forcing. Straightforward arguments suggest that for small
$\alpha$ the scalar field should consist of progressively larger eddies, while
for large $\alpha$ the scalar field is expected to have a filamentary structure
resulting from a stretch and fold mechanism. Confirming this, we proceed to
forced/dissipative dispersive numerical experiments under weakly non-local to
local conditions. For $\epsilon \sim 1$, there is quantitative agreement
between non-dispersive estimates and observed slopes in the inverse energy
transfer regime. On the other hand, forward enstrophy transfer regime always
yields slopes that are significantly steeper than the corresponding
non-dispersive estimate. Additional simulations show the scaling in the inverse
regime to be sensitive to the strength of the dispersive term : specifically,
as $\epsilon$ decreases, the inertial-range shortens and we also observe that
the slope of the power-law decreases. On the other hand, for the same range of
$\epsilon$ values, the forward regime scaling is fairly universal.


title:
Allowed charge transfers between coherent conductors driven by a
  time-dependent scatterer

abstract:
  We derive constraints on the statistics of the charge transfer between two
conductors in the model of arbitrary time-dependent instant scattering of
non-interacting fermions at zero temperature. The constraints are formulated in
terms of analytic properties of the generating function: its zeroes must lie on
the negative real axis. This result generalizes existing studies for scattering
by a time-independent scatterer under time-dependent bias voltage.


title: De Sitter Space and Eternity

abstract:
  This paper explores infrared quantum effects in the de Sitter space. The
notion of "eternal manifolds" is introduced and it is shown that in most cases
the de Sitter space doesn't belong to this class. It is unstable under small
perturbations which may cause a breakdown of the de Sitter symmetry. The de
Sitter string sigma model is discussed. It is argued that the gauge theory at
the complex coupling is dual to the matrix elements of vertex operators in the
de Sitter space, taken between the Bunch - Davies vacuum and the "out" state
without particles.The described infrared effects are likely to screen away the
cosmological constant.


title: Compactifying normal algebraic spaces

abstract:
  The author wrote this note after being asked about the existence of
compactifications of algebraic spaces. Subsequent to posting the article to the
math arXiv, the author learned from Yutakaa Matsuura that the results of this
paper had been proved by Raoult in 1971, using the same techniques. Since
Raoult's article may be unknown to those working in the field, the author is
keeping this preprint on the arXiv server. However, he makes no claim of
originality.


title: On the structure of quasi-stationary competing particle systems

abstract:
  We study point processes on the real line whose configurations $X$ are
locally finite, have a maximum and evolve through increments which are
functions of correlated Gaussian variables. The correlations are intrinsic to
the points and quantified by a matrix $Q=\{q_{ij}\}_{i,j\in\mathbb{N}}$. A
probability measure on the pair $(X,Q)$ is said to be quasi-stationary if the
joint law of the gaps of $X$ and of $Q$ is invariant under the evolution. A
known class of universally quasi-stationary processes is given by the Ruelle
Probability Cascades (RPC), which are based on hierarchically nested
Poisson--Dirichlet processes. It was conjectured that up to some natural
superpositions these processes exhausted the class of laws which are robustly
quasi-stationary. The main result of this work is a proof of this conjecture
for the case where $q_{ij}$ assume only a finite number of values. The result
is of relevance for mean-field spin glass models, where the evolution
corresponds to the cavity dynamics, and where the hierarchical organization of
the Gibbs measure was first proposed as an ansatz.


title:
Problems of the Sensitivity Parameter and Its Relation to the
  Time-varying Fundamental Couplings Problems

abstract:
  The sensitivity parameter is widely used for quantifying fine tuning.
However, examples show it fails to give correct results under certain
circumstances. We argue that these problems only occur when calculating the
sensitivity of a dimensionful mass parameter at one energy scale to the
variation of a dimensionless coupling constant at another energy scale. Thus,
by mechanisms such as dynamical symmetry breaking etc, the high sensitivity of
the energy scale parameter (\Lambda) to the dimensionless coupling constant can
affect the reliability of the sensitivity parameter through the renormalization
invariant factor of the dimensionful parameter. Theoretically, These phenomena
are similar to the problems associated with the time-varying coupling constant
discovered recently. We argue that, the reliability of the sensitivity
parameter can be improved if it is used properly.


title: Hadrons in Nuclei: Experiments and Perspectives

abstract:
  The question of the origin of hadron masses is one major issue in the
understanding of the strong interaction. The challenge is addressed by
searching for indications of in-medium modifications of hadron properties and
studying hadrons in nuclei. The quest driving in-medium studies is to
understand the origin of hadron masses in the context of spontaneous chiral
symmetry breaking.
  The experimental status of the modification of hadron properties in the
nuclear medium is discussed including experiments using hadron, heavy-ion, and
photon beams. Particular emphasis is put on the production of light mesons from
nuclei.
  A number of experimental programs is underway to provide a detailed
comparison of properties of free hadrons and hadrons embedded in nuclei. The
existing experimental efforts are discussed and possibilities are introduced
for the new WASA-at-COSY facility, initially focussed on investigations of
symmetries and symmetry breaking, to contribute to the field.


title: Dynamical Lorentz and CPT symmetry breaking in a 4D four-fermion model

abstract:
  In a 4D chiral Thirring model we analyse the possibility that radiative
corrections may produce spontaneous breaking of Lorentz and CPT symmetry. By
studying the effective potential, we verified that the chiral current
$\bar\psi\gamma^{\mu} \gamma_5 \psi$ may assume a nonzero vacuum expectation
value which triggers the Lorentz and CPT violations. Furthermore, by making
fluctuations on the minimum of the potential we dynamically induce a bumblebee
like model containing a Chern-Simons term.


title: In Search of Quantum de Sitter Space: Generalizing the Kodama State

abstract:
  The Kodama state is unique in being an exact solution to all the constraints
of quantum gravity that also has a well defined semi-classical interpretation
as the quantum version of a classical spacetime, namely de Sitter or anti-de
sitter space. Despite this, the state fails to pass some of the key tests of a
physically realistic quantum state. In an attempt to resolve this problem, we
track down the root of the problem to a choice for a particular parameter: the
Immirzi parameter. The Kodama state takes this parameter to be complex, whereas
modern formulations of canonical quantum gravity require that the parameter is
real. We generalize the Kodama state to real values of the Immirzi parameter,
and find that the generalization opens up a large Hilbert space of states, one
of which can be directly interpreted as particular slicing of de Sitter space.
We then show that these states resolve, or are expected to resolve many of the
problems associated with the original version of the Kodama state. In order to
resolve the interpretation of the multitude of states, we develop a new model
of covariant classical and quantum gravity where the full Lorentz group is
retained as a local symmetry group, and the canonical evolution generated by
the constraints has a close relation to a larger group: the de Sitter group.
This formalism gives strong evidence that the multitude of generalized Kodama
states can be unified into a single quantum state that is quantum de Sitter
space.


title: Uniform estimates for some paraproducts

abstract:
  We establish $L^p\times L^q$ to $L^r$ estimates for some paraproducts, which
arise in the study of the bilinear Hilbert transform along curves.


title: A bilinear oscillatory integral along parabolas

abstract:
  We establish an $L^\infty\times L^2 \to L^2$ norm estimate for a bilinear
oscillatory integral along parabolas incorporating oscillatory factors
$e^{i|t|^{-\beta}}$.


title: Three lectures on elliptic surfaces and curves of high rank

abstract:
  Over the past two years we have improved several of the (Mordell-Weil) rank
records for elliptic curves over Q and nonconstant elliptic curves over Q(t).
For example, we found the first example of a curve E/Q with 28 independent
points P_i in E(Q) (the previous record was 24, by R.Martin and W.McMillen
2000), and the first example of a curve over Q with Mordell-Weil group
isomorphic with (Z/2Z) x Z^18 (the previous rank record for a curve with a
2-torsion point was 15, by Dujella 2002). In these lectures we give some of the
background, theory, and computational tools that led to these new records and
related applications.
  I Context and overview: the theorems of Mordell(-Weil) and Mazur; the rank
problem; the approaches of Neron--Shioda and Mestre; elliptic surfaces and
Neron specialization; fields other than Q.
  II Elliptic surfaces and K3 surfaces: the Mordell-Weil and Neron-Severi
groups; K3 surfaces of high Neron-Severi rank and their moduli; an elliptic K3
surface over Q of Mordell-Weil rank 17. Some other applications of K3 surfaces
of high rank and their moduli.
  III Computational issues, techniques, and results: slices of Niemeier
lattices; finding and transforming models of K3 surfaces of high rank;
searching for good specializations. Summary of new rank records for elliptic
curves.


title:
A Quantum Cosmology: No Dark Matter, Dark Energy nor Accelerating
  Universe

abstract:
  We show that modelling the universe as a pre-geometric system with emergent
quantum modes, and then constructing the classical limit, we obtain a new
account of space and gravity that goes beyond Newtonian gravity even in the
non-relativistic limit. This account does not require dark matter to explain
the spiral galaxy rotation curves, and explains as well the observed
systematics of black hole masses in spherical star systems, the bore hole $g$
anomalies, gravitational lensing and so on. As well the dynamics has a Hubble
expanding universe solution that gives an excellent parameter-free account of
the supernovae and gamma-ray-burst red-shift data, without dark energy or dark
matter. The Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) metric is derived
from this dynamics, but is shown not satisfy the General Relativity based
Friedmann equations. It is noted that General Relativity dynamics only permits
an expanding flat 3-space solution if the energy density in the pressure-less
dust approximation is non-zero. As a consequence dark energy and dark matter
are required in this cosmological model, and as well the prediction of a future
exponential accelerating Hubble expansion. The FLRW $\Lambda$CDM model
data-based parameter values, $\Omega_\Lambda=0.73$, $\Omega_{DM}=0.27$, are
derived within the quantum cosmology model, but are shown to be merely
artifacts of using the Friedmann equations in fitting the red-shift data.


title:
Entanglement, weak values, and the precise inference of joint
  measurement outcomes for non-commuting observable pairs

abstract:
  The problem of inferring the outcome of a simultaneous measurement of two
non-commuting observables is addressed. We show that for certain pairs with
dense spectra, precise inferences of the measurement outcomes are possible in
pre-and post-selected ensembles, and if the selections involve entangled states
with some other system. We show that the problem is related to the problem of
assigning weak values to a continuous family of operators, and give explicit
examples where this problem is solvable. Some foundational implications are
briefly discussed.


title:
Radio Jets in Galaxies with Actively Accreting Black Holes: new insights
  from the SDSS

abstract:
  The majority of nearby radio-loud AGN are found in massive, old elliptical
galaxies with weak emission lines. At high redshifts,however, most known radio
AGN have strong emission lines. In this paper, we examine a subset of radio AGN
with emission lines selected from the Sloan Digital Sky Survey. The probability
for a nearby radio AGN to have emission lines is a strongly decreasing function
of galaxy mass and an increasing function of radio luminosity above 10^25 W/Hz.
Emission line and radio luminosities are correlated, but with large dispersion.
At a given radio power, AGN with small black holes have higher [OIII]
luminosities (which we interpret as higher accretion rates) than AGN with big
black holes. However, if we scale both radio and emission line luminosities by
the black hole mass, we find a correlation between normalized radio power and
accretion rate in Eddington units that is independent of black hole mass. There
is also a clear correlation between normalized radio power and the age of the
stellar population in the galaxy. Present-day AGN with the highest normalized
radio powers are confined to galaxies with small black holes. High-redshift,
high radio-luminosity AGN could be explained if big black holes were similarly
active at earlier cosmic epochs. To investigate why only a small fraction of
emission line AGN become radio loud, we create matched samples of radio-loud
and radio-quiet AGN and compare their host galaxy properties and environments.
The main difference lies in their environments; our local density estimates are
a factor 2 larger around the radio-loud AGN. We propose a scenario in which
radio-loud AGN with emission lines are located in galaxies where accretion of
both cold and hot gas can occur simultaneously. (Abridged)


title: Cosmological Constraints on Dissipative Models of Inflation

abstract:
  (Abridged) We study dissipative inflation in the regime where the dissipative
term takes a specific form, \Gamma=\Gamma(\phi), analyzing two models in the
weak and strong dissipative regimes with a SUSY breaking potential. After
developing intuition about the predictions from these models through analytic
approximations, we compute the predicted cosmological observables through full
numerical evolution of the equations of motion, relating the mass scale and
scale of dissipation to the characteristic amplitude and shape of the
primordial power spectrum. We then use Markov Chain Monte Carlo techniques to
constrain a subset of the models with cosmological data from the cosmic
microwave background (WMAP three-year data) and large scale structure (SDSS
Luminous Red Galaxy power spectrum). We find that the posterior distributions
of the dissipative parameters are highly non-Gaussian and their allowed ranges
agree well with the expectations obtained using analytic approximations. In the
weak regime, only the mass scale is tightly constrained; conversely, in the
strong regime, only the dissipative coefficient is tightly constrained. A lower
limit is seen on the inflation scale: a sub-Planckian inflaton is disfavoured
by the data. In both weak and strong regimes, we reconstruct the limits on the
primordial power spectrum and show that these models prefer a {\it red}
spectrum, with no significant running of the index. We calculate the reheat
temperature and show that the gravitino problem can be overcome with large
dissipation, which in turn leads to large levels of non-Gaussianity: if
dissipative inflation is to evade the gravitino problem, the predicted level of
non-Gaussianity might be seen by the Planck satellite.


title:
Fermion family number and the Z-Z$^{\prime}$ mixing in the 3-3-1 model
  with right-handed neutrinos

abstract:
  Theoretical consistency of the 3-3-1 model with right-handed neutrinos
demands that the number of family of fermions be exactly equal to three. In
this brief report we show that such theoretical requirement results in a clean
and severe bound on the Z-Z$^{\prime}$ mixing angle: $-3,979\times
10^{-3}<\phi<1,309\times 10^{-4} {with 90% CL}$.


title: Flux, Gaugino Condensation and Anti-Branes in Heterotic M-theory

abstract:
  We present the potential energy due to flux and gaugino condensation in
heterotic M-theory compactifications with anti-branes in the vacuum. For
reasons which we explain in detail, the contributions to the potential due to
flux are not modified from those in supersymmetric contexts. The discussion of
gaugino condensation is, however, changed by the presence of anti-branes. We
show how a careful microscopic analysis of the system allows us to use standard
results in supersymmetric gauge theory in describing such effects - despite the
explicit supersymmetry breaking which is present. Not surprisingly, the
significant effect of anti-branes on the threshold corrections to the gauge
kinetic functions greatly alters the potential energy terms arising from
gaugino condensation.


title:
A Connection between Star Formation in Nuclear Rings and their Host
  Galaxies

abstract:
  We present results from a photometric H-alpha survey of 22 nuclear rings,
aiming to provide insight into their star formation properties, including age
distribution, dynamical timescales, star formation rates, and galactic bar
influence. We find a clear relationship between the position angles and
ellipticities of the rings and those of their host galaxies, which indicates
the rings are in the same plane as the disk and circular. We use population
synthesis models to estimate ages of each H-alpha emitting HII region, which
range from 1 Myr to 10 Myrs throughout the rings. We find that approximately
half of the rings contain azimuthal age gradients that encompass at least 25%
of the ring, although there is no apparent relationship between the presence or
absence of age gradients and the morphology of the rings or their host
galaxies. NGC1343, NGC1530, and NGC4321 show clear bipolar age gradients, where
the youngest HII regions are located near the two contact points of the bar and
ring. We speculate in these cases that the gradients are related to an
increased mass inflow rate and/or an overall higher gas density in the ring,
which would allow for massive star formation to occur on short timescales,
after which the galactic rotation would transport the HII regions around the
ring as they age. Two-thirds of the barred galaxies show correlation between
the locations of the youngest HII region(s) in the ring and the location of the
contact points, which is consistent with predictions from numerical modeling.


title: Values of characters sums for finite unitary groups

abstract:
  A known result for the finite general linear group $\GL(n,\FF_q)$ and for the
finite unitary group $\U(n,\FF_{q^2})$ posits that the sum of the irreducible
character degrees is equal to the number of symmetric matrices in the group.
Fulman and Guralnick extended this result by considering sums of irreducible
characters evaluated at an arbitrary conjugacy class of $\GL(n,\FF_q)$. We
develop an explicit formula for the value of the permutation character of
$\U(2n,\FF_{q^2})$ over $\Sp(2n,\FF_q)$ evaluated an an arbitrary conjugacy
class and use results concerning Gelfand-Graev characters to obtain an
analogous formula for $\U(n,\FF_{q^2})$ in the case where $q$ is an odd prime.
These results are also given as probabilistic statements.


title:
Measurement of the p\bar{p}\to WZ + X cross section at \sqrt{s}=1.96 TeV
  and limits on WWZ trilinear gauge couplings

abstract:
  We present measurements of the process $p\bar{p} \to WZ+X \to \ell^{\prime}
\nu_{\ell^{\prime}} \ell \bar{\ell}$ at $\sqrt{s}=1.96$ TeV, where $\ell$ and
$\ell^{\prime}$ are electrons or muons. Using 1 fb$^{-1}$ of data from the D0
experiment, we observe 13 candidates with an expected background of $4.5\pm0.6$
events and measure a cross section $\sigma(WZ)=2.7^{+1.7}_{-1.3}$ pb. From the
number of observed events and the $Z$ boson transverse momentum distribution,
we limit the trilinear $WWZ$ gauge couplings to $-0.17 \le \lambda_Z \le 0.21$
$(\Delta \kappa_Z = 0)$ at the 95% C.L. for a form factor scale $\Lambda=2$
TeV. Further, assuming that $\Delta g^Z_1 = \Delta\kappa_Z$, we find $-0.12 \le
\Delta\kappa_Z \le 0.29$ $(\lambda_Z=0)$ at the 95% C.L. These are the most
restrictive limits on the $WWZ$ couplings available to date.


title:
Interplay of ferromagnetism and triplet superconductivity in a Josephson
  junction

abstract:
  In this paper we extend our earlier analysis of the novel Josephson effect in
triplet superconductor--ferromagnet--triplet superconductor (TFT) junctions [B.
Kastening \emph{et al.}, Phys. Rev. Lett. {\bf{96}}, 047009 (2006)]. In our
more general formulation of the TFT junction we allow for potential scattering
at the barrier and an arbitrary orientation of the ferromagnetic moment.
Several new effects are found upon the inclusion of these extra terms: for
example, we find that a Josephson current can flow even when there is vanishing
phase difference between the superconducting condensates on either side of the
barrier. The critical current for a barrier with magnetization parallel to the
interface is calculated as a function of the junction parameters, and is found
to display strong non-analyticities. Furthermore, the Josephson current
switches first identified in our previous work are found to be robust features
of the junction, while the unconventional temperature-dependence of the current
is very sensitive to the extra terms in the barrier Hamiltonian.


title: Hyperbolic geometry of multiply twisted knots

abstract:
  We investigate the geometry of hyperbolic knots and links whose diagrams have
a high amount of twisting of multiple strands. We find information on volume
and certain isotopy classes of geodesics for the complements of these links,
based only on a diagram. The results are obtained by finding geometric
information on generalized augmentations of these links.


title: From Littlewood-Richardson sequences to subgroup embeddings and back

abstract:
  Let $\alpha$, $\beta$, and $\gamma$ be partitions describing the isomorphism
types of the finite abelian $p$-groups $A$, $B$, and $C$. From theorems by
Green and Klein it is well-known that there is a short exact sequence $0\to
A\to B\to C\to 0$ of abelian groups if and only if there is a
Littlewood-Richardson sequence of type $(\alpha,\beta,\gamma)$. Starting from
the observation that a sequence of partitions has the LR property if and only
if every subsequence of length 2 does, we demonstrate how LR-sequences of
length two correspond to embeddings of a $p^2$-bounded subgroup in a finite
abelian $p$-group. Using the known classification of all such embeddings we
derive short proofs of the theorems by Green and Klein.


title:
A possible scenario for the mechanism of high-Tc superconductivity based
  on experimental data

abstract:
  The issue of the mechanism of high-Tc superconductivity remains open. In this
contribution, we propose a new scenario for the mechanism of superconductivity
in cuprates based on analysis of experimental data, mainly tunneling, neutron
scattering and muon-spin-relaxation data, made earlier (see e.g. Mod. Phys.
Lett. B 19 (2005) 743). A specific feature of this scenario is the mechanism of
the establishment of long-range phase coherence among Cooper pairs, based on
recent experimental data obtained in nonsuperconducting materials.


title: PSR B1257+12: a quark star with planets?

abstract:
  A recent observation has shown that PSR B1257+12 could have quite small X-ray
emitting area, only about 2000 m$^2$, which is more than three orders smaller
than the canonical polar cap size. We suggest here that PSR B1257+12 could be a
low-mass quark star with radius of $R \simeq 0.6$ km and mass of $M \simeq
3\times10^{-4}\msun$. Such a low-mass quark star system may form in an
accretion induced collapse process or a collision process of two quark stars.


title: Generation of 10-GHz clock sequential time-bin entanglement

abstract:
  This letter reports telecom-band sequential time-bin entangled photon-pair
generation at a repetition rate of 10 GHz in periodically-poled
reverse-proton-exchange lithium niobate waveguides based on mode
demultiplexing. With up-conversion single-photon detectors, we observed a
two-photon-interference-fringe visibility of 85.32% without subtraction of
accidental noise contributions, which can find broad application in quantum
information and quantum entanglement research.


title: Feshbach resonances in ultracold ^{6,7}Li + ^{23}Na atomic mixtures

abstract:
  We report a theoretical study of Feshbach resonances in $^{6}$Li + $^{23}$Na
and $^{7}$Li + $^{23}$Na mixtures at ultracold temperatures using new accurate
interaction potentials in a full quantum coupled-channel calculation. Feshbach
resonances for $l=0$ in the initial collisional open channel $^6$Li$(f=1/2,
m_f=1/2) + ^{23}$Na$(f=1, m_f=1)$ are found to agree with previous
measurements, leading to precise values of the singlet and triplet scattering
lengths for the $^{6,7}$Li$+^{23}$Na pairs. We also predict additional Feshbach
resonances within experimentally attainable magnetic fields for other collision
channels.


title: A new approach to the study of quasi-normal modes of rotating stars

abstract:
  We propose a new method to study the quasi-normal modes of rotating
relativistic stars. Oscillations are treated as perturbations in the frequency
domain of the stationary, axisymmetric background describing a rotating star.
The perturbed quantities are expanded in circular harmonics, and the resulting
2D-equations they satisfy are integrated using spectral methods in the
(r,theta)-plane. The asymptotic conditions at infinity, needed to find the mode
frequencies, are implemented by generalizing the standing wave boundary
condition commonly used in the non rotating case. As a test, the method is
applied to find the quasi-normal mode frequencies of a slowly rotating star.


title:
Shape and local growth for multidimensional branching random walks in
  random environment

abstract:
  We study branching random walks in random environment on the $d$-dimensional
square lattice, $d \geq 1$. In this model, the environment has finite range
dependence, and the population size cannot decrease. We prove limit theorems
(laws of large numbers) for the set of lattice sites which are visited up to a
large time as well as for the local size of the population. The limiting shape
of this set is compact and convex, though the local size is given by a concave
growth exponent. Also, we obtain the law of large numbers for the logarithm of
the total number of particles in the process.


title: Developing A Chemical Evolutionary Sequence for Low-mass Starless Cores

abstract:
  I review the basic processes that may be used to develop a chemical
evolutionary sequence for low-mass starless cores. I highlight observational
results from the Arizona Radio Observatory-Green Bank Survey. Observations were
performed with the SMT 10-m, ARO 12-m, and GBT 100-m toward a sample of 25
nearby (D < 400 pc) low-mass starless cores which have radiative transfer
models of the 850 $\mu$m emission and observed SED (160 - 1300 um). The cores
were observed in the lines of NH3 (1,1) and (2,2), o-NH2D 1_{11} - 1_{01}, C2S
1_2 - 2_1, C3S 4 - 3, HCN 1 - 0, HC5N 9 - 8, HC7N 21 - 20, C18O and C17O 2 - 1,
and p-H2CO 1_{01} - 0_{00}.


title: Age and metallicity of the bulges in lenticular galaxies

abstract:
  Panoramic spectroscopic data of the sample of 80 nearby lenticular galaxies
obtained with the Multi-Pupil Fiber Spectrograph of the 6-m telescope are
presented. The SSP-equivalent ages, [Z/H], and [Mg/Fe] are determined through
the Lick indices H-beta, Mgb, and <Fe> separately for the nuclei and for the
bulges. About a half of the sample contain chemically distinct nuclei, more
metal-rich and younger than the bulges. The correlations of the stellar
population properties for the nearby S0s are discussed.


title:
Z boson decay to photon plus Kaluza-Klein graviton: large extra
  dimensional bounds

abstract:
  We consider the phenomenology of the decay of a Z boson into a photon and a
Kaluza-Klein excitation of the graviton in the ADD model. Using LEP data, we
obtain an upper bound on the branching ratio corresponding to this process of
~10^-11. We also investigate energy profiles of the process.


title: Asymptotic estimates for phi functions for subsets of {m+1, m+2,...,n}

abstract:
  Let f(m,n) denote the number of relatively prime subsets of {m+1,m+2,...,n},
and let Phi(m,n) denote the number of subsets A of {m+1,m+2,...,n} such that
gcd(A) is relatively prime to n. Let f_k(m,n) and Phi_k(m,n) be the analogous
counting functions restricted to sets of cardinality k. Simple explicit
formulas and asymptotic estimates are obtained for these four functions.


title:
Taming the Yukawa potential singularity: improved evaluation of bound
  states and resonance energies

abstract:
  Using the tools of the J-matrix method, we absorb the 1/r singularity of the
Yukawa potential in the reference Hamiltonian, which is handled analytically.
The remaining part, which is bound and regular everywhere, is treated by an
efficient numerical scheme in a suitable basis using Gauss quadrature
approximation. Analysis of resonance energies and bound states spectrum is
performed using the complex scaling method, where we show their trajectories in
the complex energy plane and demonstrate the remarkable fact that bound states
cross over into resonance states by varying the potential parameters.


title: Stabilizing the Runaway Quiver in Supergravity

abstract:
  We study stabilizations of the supersymmetry breaking runaway quiver in
string embeddings. Calculations are performed in four dimensional effective
supergravity. Constraints on closed string fields in a type IIA construction
are given. The particular case of stabilization by stringy instanton effects in
a type IIB model is considered.


title: On the realization of double occurrence words

abstract:
  Let S be a double occurrence word, and let M_S be the word's interlacement
matrix, regarded as a matrix over GF(2). Gauss addressed the question of which
double occurrence words are realizable by generic closed curves in the plane.
We reformulate answers given by Rosenstiehl and by de Fraysseix and Ossona de
Mendez to give new graph-theoretic and algebraic characterizations of
realizable words. Our algebraic characterization is especially pleasing: S is
realizable if and only if there exists a diagonal matrix D_S such that M_S+D_S
is idempotent over GF(2).


title:
Quantum Hall Transition near a Fermion Feshbach Resonance in a Rotating
  Trap

abstract:
  We consider two-species of fermions in a rotating trap that interact via an
s-wave Feshbach resonance, at total Landau level filling factor two (or one for
each species). We show that the system undergoes a quantum phase transition
from a fermion integer quantum Hall state to a boson fractional quantum Hall
state as the pairing interaction strength increases, with the transition
occurring near the resonance. The effective field theory for the transition is
shown to be that of a (emergent) massless relativistic bosonic field coupled to
a Chern-Simons gauge field, with the coupling giving rise to semionic
statistics to the emergent particles.


title:
An Extension to an Algebraic Method for Linear Time-Invariant System and
  Network Theory: The full AC-Calculus

abstract:
  Being inspired by phasor analysis in linear circuit theory, and its algebraic
counterpart - the AC-(operational)-calculus for sinusoids developed by W.
Marten and W. Mathis - we define a complex structure on several spaces of
real-valued elementary functions. This is used to algebraize inhomogeneous
linear ordinary differential equations with inhomogenities stemming from these
spaces. Thus we deduce an effective method to calculate particular solutions of
these ODEs in a purely algebraic way.


title: Bayesian Classification and Regression with High Dimensional Features

abstract:
  This thesis responds to the challenges of using a large number, such as
thousands, of features in regression and classification problems.
  There are two situations where such high dimensional features arise. One is
when high dimensional measurements are available, for example, gene expression
data produced by microarray techniques. For computational or other reasons,
people may select only a small subset of features when modelling such data, by
looking at how relevant the features are to predicting the response, based on
some measure such as correlation with the response in the training data.
Although it is used very commonly, this procedure will make the response appear
more predictable than it actually is. In Chapter 2, we propose a Bayesian
method to avoid this selection bias, with application to naive Bayes models and
mixture models.
  High dimensional features also arise when we consider high-order
interactions. The number of parameters will increase exponentially with the
order considered. In Chapter 3, we propose a method for compressing a group of
parameters into a single one, by exploiting the fact that many predictor
variables derived from high-order interactions have the same values for all the
training cases. The number of compressed parameters may have converged before
considering the highest possible order. We apply this compression method to
logistic sequence prediction models and logistic classification models.
  We use both simulated data and real data to test our methods in both
chapters.


title:
Theory of current-driven magnetization dynamics in inhomogeneous
  ferromagnets

abstract:
  We give a brief account of recent developments in the theoretical
understanding of the interaction between electric currents and inhomogeneous
ferromagnetic order parameters. We start by discussing the physical origin of
the spin torques responsible for this interaction and construct a
phenomenological description. We then consider the electric current-induced
ferromagnetic instability and domain-wall motion. Finally, we present a
microscopic justification of the phenomenological description of current-driven
magnetization dynamics, with particular emphasis on the dissipative terms, the
so-called Gilbert damping $\alpha$ and the $\beta$ component of the adiabatic
current-driven torque.


title:
Near linear time algorithm to detect community structures in large-scale
  networks

abstract:
  Community detection and analysis is an important methodology for
understanding the organization of various real-world networks and has
applications in problems as diverse as consensus formation in social
communities or the identification of functional modules in biochemical
networks. Currently used algorithms that identify the community structures in
large-scale real-world networks require a priori information such as the number
and sizes of communities or are computationally expensive. In this paper we
investigate a simple label propagation algorithm that uses the network
structure alone as its guide and requires neither optimization of a pre-defined
objective function nor prior information about the communities. In our
algorithm every node is initialized with a unique label and at every step each
node adopts the label that most of its neighbors currently have. In this
iterative process densely connected groups of nodes form a consensus on a
unique label to form communities. We validate the algorithm by applying it to
networks whose community structures are known. We also demonstrate that the
algorithm takes an almost linear time and hence it is computationally less
expensive than what was possible so far.


title: NICMOS Observations of Shocked H_2 in Orion

abstract:
  HST NICMOS narrowband images of the shocked molecular hydrogen emission in
OMC-1 are analyzed to reveal new information on the BN/KL outflow. The
outstanding morphological feature of this region is the array of molecular
hydrogen ``fingers'' emanating from the general vicinity of IRc2 and the
presence of several Herbig-Haro objects. The NICMOS images appear to resolve
individual shock fronts. This work is a more quantitative and detailed analysis
of our data from a previous paper (Schultz etal. 1999).
  Line strengths for the H_2 1--0 S(4) plus 2--1 S(6) lines at 1.89 micron are
estimated from measurements with the Paschen_alpha continuum filter F190N at
1.90 micron, and continuum measurements at 1.66 and 2.15 micron. We compare the
observed H_2 line strengths and ratios of the 1.89 micron and 2.12 micron 1--0
S(1) lines with models for molecular cloud shock waves. Most of the data cannot
be fit by J-shocks, but are well matched by C-shocks with shock velocities in
the range of 20--45 km/s and preshock densities of 10^{4} - 10^{6} cm^{-3},
similiar to values obtained in larger beam studies which averaged over many
shocks. There is also some evidence that shocks with higher densities have
lower velocities.


title:
Spin-dependent tunneling and Coulomb blockade in ferromagnetic
  nanoparticles

abstract:
  We review studies on spin-dependent tunneling phenomena in systems containing
ferromagnetic nanoparticles. We discuss preparation methods of assembling
nanoparticles as well as the mechanisms and results of spin-dependent transport
properties. The emphasis of this review is on characteristic spin-dependent
tunneling phenomena such as enhanced tunnel magnetoresistance (TMR) due to
co-tunneling in the Coulomb blockade regime and sign changes of the TMR due to
spin accumulation in nanoparticles.


title:
The p-harmonic boundary for finitely generated groups and the first
  reduced \ell_p-cohomology

abstract:
  Let $p$ be a real number greater than one and let $G$ be a finitely
generated, infinite group. In this paper we introduce the $p$-harmonic boundary
of $G$. We then characterize the vanishing of the first reduced
$\ell^p$-cohomology of $G$ in terms of the cardinality of this boundary. Some
properties of $p$-harmonic boundaries that are preserved under rough isometries
are also given. We also study the relationship between translation invariant
linear functionals on a certain difference space of functions on $G$, the
$p$-harmonic boundary of $G$ and the first reduced $\ell^p$-cohomology of $G$.


title:
Conformal Enhancement of Holographic Scaling in Black Hole
  Thermodynamics: A Near-Horizon Heat-Kernel Framework

abstract:
  Standard thermodynamic treatments of quantum field theory in the presence of
black-hole backgrounds reproduce the black hole entropy by usually specializing
to the leading order of the heat-kernel or the high-temperature expansion. By
contrast, this work develops a hybrid framework centered on geometric spectral
asymptotics whereby these assumptions are shown to be unwarranted insofar as
black hole thermodynamics is concerned. The approach--consisting of the
concurrent use of near-horizon and heat-kernel asymptotic expansions--leads to
a proof of the holographic scaling of the entropy as a universal feature driven
by conformal quantum mechanics.


title: On Birnbaum-Saunders Inference

abstract:
  The Birnbaum-Saunders distribution, also known as the fatigue-life
distribution, is frequently used in reliability studies. We obtain adjustments
to the Birnbaum--Saunders profile likelihood function. The modified versions of
the likelihood function were obtained for both the shape and scale parameters,
i.e., we take the shape parameter to be of interest and the scale parameter to
be of nuisance, and then consider the situation in which the interest lies in
performing inference on the scale parameter with the shape parameter entering
the modeling in nuisance fashion. Modified profile maximum likelihood
estimators are obtained by maximizing the corresponding adjusted likelihood
functions. We present numerical evidence on the finite sample behavior of the
different estimators and associated likelihood ratio tests. The results favor
the adjusted estimators and tests we propose. A novel aspect of the profile
likelihood adjustments obtained in this paper is that they yield improved point
estimators and tests. The two profile likelihood adjustments work well when
inference is made on the shape parameter, and one of them displays superior
behavior when it comes to performing hypothesis testing inference on the scale
parameter. Two empirical applications are briefly presented.


title:
On the state space geometry of the Kuramoto-Sivashinsky flow in a
  periodic domain

abstract:
  The continuous and discrete symmetries of the Kuramoto-Sivashinsky system
restricted to a spatially periodic domain play a prominent role in shaping the
invariant sets of its chaotic dynamics. The continuous spatial translation
symmetry leads to relative equilibrium (traveling wave) and relative periodic
orbit (modulated traveling wave) solutions. The discrete symmetries lead to
existence of equilibrium and periodic orbit solutions, induce decomposition of
state space into invariant subspaces, and enforce certain structurally stable
heteroclinic connections between equilibria. We show, on the example of a
particular small-cell Kuramoto-Sivashinsky system, how the geometry of its
dynamical state space is organized by a rigid `cage' built by heteroclinic
connections between equilibria, and demonstrate the preponderance of unstable
relative periodic orbits and their likely role as the skeleton underpinning
spatiotemporal turbulence in systems with continuous symmetries. We also offer
novel visualizations of the high-dimensional Kuramoto-Sivashinsky state space
flow through projections onto low-dimensional, PDE representation independent,
dynamically invariant intrinsic coordinate frames, as well as in terms of the
physical, symmetry invariant energy transfer rates.


title:
A Simple Model of Direct Gauge Mediation of Metastable Supersymmetry
  Breaking

abstract:
  We construct a model of direct gauge mediation of metastable SUSY breaking by
simply deforming the Intriligator, Seiberg and Shih model in terms of a dual
meson superpotential mass term. No extra matter field is introduced. The
deformation explicitly breaks a U(1)_R symmetry and a pseudo moduli have a
nonzero VEV at one-loop. Our metastable SUSY breaking vacuum turns out to be
sufficiently long-lived. By gauging a subgroup of flavor symmetry, our model
can directly couple to the standard model, which leads to nonvanishing gaugino
mass generation. It is also shown that our model can evade the Landau pole
problem. We show the parameters in the SUSY breaking sector are
phenomenologically constrained.


title: The relationships between Invertible Module Maps X and X_z

abstract:
  If $R$ and $M$ are Hilbert modules (in the sense of R. G. Douglas and V. I.
Paulsen), we study the relationship between invertible module maps $X:R\to{M}$
and $X_{z}:R/R_{z}\to{M/M_{z}}$. In particular, for quasi-free Hilbert modules
$R$ and $M$, we provide a condition of a module map $X:R\to{M}$, such that if
$X_{z}:R/R_{z}\to{M/M_{z}}$ is invertible for every $z$ in a domain $\Omega$ in
the complex plane, then $X$ is also invertible.


title: Sums of Products of Bernoulli numbers of the second kind

abstract:
  The Bernoulli numbers b_0,b_1,b_2,.... of the second kind are defined by
\sum_{n=0}^\infty b_nt^n=\frac{t}{\log(1+t)}. In this paper, we give an
explicit formula for the sum \sum_{j_1+j_2+...+j_N=n,
j_1,j_2,...,j_N>=0}b_{j_1}b_{j_2}...b_{j_N}. We also establish a q-analogue for
\sum_{k=0}^n b_kb_{n-k}=-(n-1)b_n-(n-2)b_{n-1}.


title:
The Contribution of the Cosmological Constant to the Relativistic
  Bending of Light Revisited

abstract:
  We study the effect of the cosmological constant $\Lambda$ on the bending of
light by a concentrated spherically symmetric mass. Contrarily to previous
claims, we show that when the Schwarzschild-de Sitter geometry is taken into
account, $\Lambda$ does indeed contribute to the bending.


title: Metallicity and mean age across M33

abstract:
  New wide-field near-infrared (NIR) imaging observations of M33 were obtained
from UKIRT. These show a large population of intermediate-age stars
considerably improving on previous NIR data. The spatial distribution of super
giant stars, carbon-rich (C-rich or C stars) and oxygen-rich (O-rich or M
stars) asymptotic giant branch (AGB) stars distinguished from the NIR
colour-magnitude diagram (CMD) have been studied as well as the C/M ratio. The
Ks magnitude distribution has been interpreted using theoretical models to
derive the mean age and the mean metallicity across M33.


title:
Propagation of a quantum particle through two dimensional percolating
  systems

abstract:
  We study quantum percolation which is described by a tight-binding
Hamiltonian containing only off-diagonal hopping terms that are generally in
quenched binary disorder (zero or one). In such a system, transmission of a
quantum particle is determined by the disorder and interference effects,
leading to interesting sharp features in conductance as the energy, disorder,
and boundary conditions are varied. To aid understanding of this phenomenon, we
develop a visualization method whereby the progression of a wave packet
entering the cluster through a lead on one side and exiting from another lead
on the other side can be tracked dynamically. Using this method, we investigate
the evolution of the wave packet through transmission and reflection under
clusters of various disorder, sizes, boundary conditions, and energies. Our
results indicate the existence of two different kinds of localized regimes,
namely exponential and power law localization, depending on the amount of
disorder. Our study further suggests that there may be a delocalized state in
the 2D quantum percolation system at very low disorder. These results are based
on a finite size scaling analysis of the systems of size up to 70 x 70
(containing 4900 sites) on the square lattice.


title: The population of AM CVn stars from the Sloan Digital Sky Survey

abstract:
  The AM Canum Venaticorum stars are rare interacting white dwarf binaries,
whose formation and evolution are still poorly known. The Sloan Digital Sky
Survey provides, for the first time, a sample of 6 AM CVn stars (out of a total
population of 18) that is sufficiently homogeneous that we can start to study
the population in some detail.
  We use the Sloan sample to `calibrate' theoretical population synthesis
models for the space density of AM CVn stars. We consider optimistic and
pessimistic models for different theoretical formation channels, which yield
predictions for the local space density that are more than two orders of
magnitude apart. When calibrated with the observations, all models give a local
space density of 1-3x10^{-6} pc^{-3}, which is lower than expected.
  We discuss the implications for the formation of AM CVn stars, and conclude
that at least one of the dominant formation channels (the double-degenerate
channel) has to be suppressed relative to the optimistic models. In the
framework of the current models this suggests that the mass transfer between
white dwarfs usually cannot be stabilized. We furthermore discuss evolutionary
effects that have so far not been considered in population synthesis models,
but which could be of influence for the observed population. We finish by
remarking that, with our lower space density, the expected number of Galactic
AM CVn stars resolvable by gravitational-wave detectors like LISA should be
lowered from current estimates, to about 1,000 for a mission duration of one
year.


title: Non-equilibrium microtubule fluctuations in a model cytoskeleton

abstract:
  Biological activity gives rise to non-equilibrium fluctuations in the
cytoplasm of cells; however, there are few methods to directly measure these
fluctuations. Using a reconstituted actin cytoskeleton, we show that the
bending dynamics of embedded microtubules can be used to probe local stress
fluctuations. We add myosin motors that drive the network out of equilibrium,
resulting in an increased amplitude and modified time-dependence of microtubule
bending fluctuations. We show that this behavior results from step-like forces
on the order of 10 pN driven by collective motor dynamics.


title: Quantum Entanglement Capacity with Classical Feedback

abstract:
  For any quantum discrete memoryless channel, we define a quantity called
quantum entanglement capacity with classical feedback ($E_B$), and we show that
this quantity lies between two other well-studied quantities. These two
quantities - namely the quantum capacity assisted by two-way classical
communication ($Q_2$) and the quantum capacity with classical feedback ($Q_B$)
- are widely conjectured to be different: there exists quantum discrete
memoryless channel for which $Q_2>Q_B$. We then present a general scheme to
convert any quantum error-correcting codes into adaptive protocols for this
newly-defined quantity of the quantum depolarizing channel, and illustrate with
Cat (repetition) code and Shor code. We contrast the present notion with
entanglement purification protocols by showing that whilst the Leung-Shor
protocol can be applied directly, recurrence methods need to be supplemented
with other techniques but at the same time offer a way to improve the
aforementioned Cat code. For the quantum depolarizing channel, we prove a
formula that gives lower bounds on the quantum capacity with classical feedback
from any $E_B$ protocols. We then apply this formula to the $E_B$ protocols
that we discuss to obtain new lower bounds on the quantum capacity with
classical feedback of the quantum depolarizing channel.


title: The long-period AM CVn star SDSS J155252.48+320150.9

abstract:
  The Sloan Digital Sky Survey has been instrumental in obtaining a homogeneous
sample of the rare AM CVn stars: mass-transferring binary white dwarfs. As part
of a campaign of spectroscopic follow-up on candidate AM CVn stars from the
Sloan Digital Sky Survey, we have obtained time-resolved spectra of the g=20.2
candidate SDSS J155252.48+320150.9 on the Very Large Telescope of the European
Southern Observatory. We report an orbital period of 3376.3+/-0.3 s, or
56.272+/-0.005 min, based on an observed `S-wave' in the helium emission lines
of the spectra. This confirms the ultracompact nature of the binary. Despite
its relative closeness to the orbital period minimum for hydrogen-rich donors,
there is no evidence for hydrogen in the spectra. We thus classify SDSS J1552
as a new bona fide AM CVn star, with the second-longest orbital period after
V396 Hya (P=65.5 min). The continuum of SDSS J1552 is compatible with either a
blackbody or helium atmosphere of 12,000-15,000 K. If this represents the
photosphere of the accreting white dwarf, as is expected, it puts the accretor
at the upper end of the temperature range predicted by thermal evolution
models. This suggests that SDSS J1552 consists of (or formerly consisted of)
relatively high-mass components.


title:
Baryonic Acoustic Oscillations in 21cm Emission: A Probe of Dark Energy
  out to High Redshifts

abstract:
  Low-frequency observatories are currently being constructed with the goal of
detecting redshifted 21cm emission from the epoch of reionization. These
observatories will also be able to detect intensity fluctuations in the
cumulative 21cm emission after reionization, from hydrogen in unresolved damped
Ly-alpha absorbers (such as gas rich galaxies) down to a redshift z~3.5. The
inferred power spectrum of 21cm fluctuations at all redshifts will show
acoustic oscillations, whose co-moving scale can be used as a standard ruler to
infer the evolution of the equation of state for the dark energy. We find that
the first generation of low-frequency experiments (such as MWA or LOFAR) will
be able to constrain the acoustic scale to within a few percent in a redshift
window just prior to the end of the reionization era, provided that foregrounds
can be removed over frequency band-passes of >8MHz. This sensitivity to the
acoustic scale is comparable to the best current measurements from galaxy
redshift surveys, but at much higher redshifts. Future extensions of the first
generation experiments (involving an order of magnitude increase in the
antennae number of the MWA) could reach sensitivities below one percent in
several redshift windows and could be used to study the dark energy in the
unexplored redshift regime of 3.5<z<12. Moreover, new experiments with antennae
designed to operate at higher frequencies would allow precision measurements
(<1%) of the acoustic peak to be made at more moderate redshifts (1.5<z<3.5),
where they would be competitive with ambitious spectroscopic galaxy surveys
covering more than 1000 square degrees. Together with other data sets,
observations of 21cm fluctuations will allow full coverage of the acoustic
scale from the present time out to z~12.


title:
The Phase Behavior of Mixed Lipid Membranes in Presence of the Rippled
  Phase

abstract:
  We propose a model describing liquid-solid phase coexistence in mixed lipid
membranes by including explicitly the occurrence of a rippled phase. For a
single component membrane, we employ a previous model in which the membrane
thickness is used as an order parameter. As function of temperature, this model
properly accounts for the phase behavior of the three possible membrane phases:
solid, liquid and the rippled phase. Our primary aim is to explore extensions
of this model to binary lipid mixtures by considering the composition
dependence of important model parameters. The obtained phase diagrams show
various liquid, solid and rippled phase coexistence regions, and are in
quantitative agreement with the experimental ones for some specific lipid
mixtures.


title: Radio and gamma-ray emissions from pulsars: possible observational tests

abstract:
  Many models for the pulsar radio and $\gamma$-ray emissions have been
developed. The tests for these models using observational data are very
important. Tests for the pulsar radio emission models using frequency-altitude
relation are presented in this paper. In the radio band, the mean pulse
profiles evolve with observing frequencies. There are various styles of pulsar
profile - frequency evolutions (which we call as "beam evolution" figure), e.g.
some pulsars show that mean pulse profiles are wider and core emission is
higher at higher frequencies than that at lower frequencies, but some other
pulsars show completely the contrary results. We show that all these "beam
evolution" figures can be understood by the Inverse Compton Scattering(ICS)
model (see Qiao at al.2001 also). An important observing test is that, for a
certain observing frequency different emission components are radiated from the
different heights. For the $\gamma$-ray pulsars, the geometrical method (Wang
et al. 2006) can be used to diagnose the radiation location for the
$\gamma$-ray radiation. As an example, Wang et al. (2006) constrain the
$\gamma$-ray radiation location of PSR B1055-52 to be the place near the null
charge surface. Here we show that Wang's result matches the proposed radiation
locations by the annular gap model as well as the outer gap models.


title: Denaturation transition of stretched DNA

abstract:
  We generalize the Poland-Scheraga model to consider DNA denaturation in the
presence of an external stretching force. We demonstrate the existence of a
force-induced DNA denaturation transition and obtain the temperature-force
phase diagram. The transition is determined by the loop exponent $c$ for which
we find the new value $c=4\nu-1/2$ such that the transition is second order
with $c=1.85<2$ in $d=3$. We show that a finite stretching force $F$
destabilizes DNA, corresponding to a lower melting temperature $T(F)$, in
agreement with single-molecule DNA stretching experiments.


title: Monte Carlo Simulation for the MAGIC-II System

abstract:
  Within the year 2007, MAGIC will be upgraded to a two telescope system at La
Palma. Its main goal is to improve the sensitivity in the
stereoscopic/coincident operational mode. At the same time it will lower the
analysis threshold of the currently running single MAGIC telescope. Results
from the Monte Carlo simulations of this system will be discussed. A comparison
of the two telescope system with the performance of one single telescope will
be shown in terms of sensitivity, angular resolution and energy resolution.


title: Exact Solvability of Two-Dimensional Real Singular Morse Potential

abstract:
  The supersymmetric approach in the form of second order intertwining
relations is used to prove the exact solvability of two-dimensional Schrodinger
equation with generalized two-dimensional Morse potential for $a_0=-1/2$. This
two-parametric model is not amenable to conventional separation of variables,
but it is completely integrable: the symmetry operator of fourth order in
momenta exists. All bound state energies are found explicitly, and all
corresponding wave functions are built analytically. By means of shape
invariance property, the result is extended to the hierarchy of Morse models
with arbitrary integer and half-integer values $a_k=-(k+1)/2.$


title: Incremental Satisfiability and Implication for UTVPI Constraints

abstract:
  Unit two-variable-per-inequality (UTVPI) constraints form one of the largest
class of integer constraints which are polynomial time solvable (unless P=NP).
There is considerable interest in their use for constraint solving, abstract
interpretation, spatial databases, and theorem proving. In this paper we
develop a new incremental algorithm for UTVPI constraint satisfaction and
implication checking that requires O(m + n log n + p) time and O(n+m+p) space
to incrementally check satisfiability of m UTVPI constraints on n variables and
check implication of p UTVPI constraints.


title: Algebraic characterization of logically defined tree languages

abstract:
  We give an algebraic characterization of the tree languages that are defined
by logical formulas using certain Lindstr\"om quantifiers. An important
instance of our result concerns first-order definable tree languages. Our
characterization relies on the usage of preclones, an algebraic structure
introduced by the authors in a previous paper, and of the block product
operation on preclones. Our results generalize analogous results on finite word
languages, but it must be noted that, as they stand, they do not yield an
algorithm to decide whether a given regular tree language is first-order
definable.


title: Order 1 autoregressive process of finite length

abstract:
  The stochastic processes of finite length defined by recurrence relations
request additional relations specifying the first terms of the process
analogously to the initial conditions for the differential equations. As a
general rule, in time series theory one analyzes only stochastic processes of
infinite length which need no such initial conditions and their properties are
less difficult to be determined. In this paper we compare the properties of the
order 1 autoregressive processes of finite and infinite length and we prove
that the time series length has an important influence mainly if the serial
correlation is significant. These different properties can manifest themselves
as transient effects produced when a time series is numerically generated. We
show that for an order 1 autoregressive process the transient behavior can be
avoided if the first term is a Gaussian random variable with standard deviation
equal to that of the theoretical infinite process and not to that of the white
noise innovation.


title:
Variational formulation of ideal fluid flows according to gauge
  principle

abstract:
  On the basis of the gauge principle of field theory, a new variational
formulation is presented for flows of an ideal fluid. The fluid is defined
thermodynamically by mass density and entropy density, and its flow fields are
characterized by symmetries of translation and rotation. The rotational
transformations are regarded as gauge transformations as well as the
translational ones. In addition to the Lagrangians representing the translation
symmetry, a structure of rotation symmetry is equipped with a Lagrangian
$\Lambda_A$ including the vorticity and a vector potential bilinearly. Euler's
equation of motion is derived from variations according to the action
principle. In addition, the equations of continuity and entropy are derived
from the variations. Equations of conserved currents are deduced as the Noether
theorem in the space of Lagrangian coordinate $\ba$. Without $\Lambda_A$, the
action principle results in the Clebsch solution with vanishing helicity. The
Lagrangian $\Lambda_A$ yields non-vanishing vorticity and provides a source
term of non-vanishing helicity. The vorticity equation is derived as an
equation of the gauge field, and the $\Lambda_A$ characterizes topology of the
field. The present formulation is comprehensive and provides a consistent basis
for a unique transformation between the Lagrangian $\ba$ space and the Eulerian
$\bx$ space. In contrast, with translation symmetry alone, there is an
arbitrariness in the ransformation between these spaces.


title: False Vacuum in the Supersymmetric Mass Varying Neutrinos Model

abstract:
  We present detailed analyses of the vacuum structure of the scalar potential
in a supersymmetric Mass Varying Neutrinos model. The observed dark energy
density is identified with false vacuum energy and the dark energy scale of
order $(10^{-3}eV)^4$ is understood by gravitationally suppressed supersymmetry
breaking scale, $F({TeV})^2/M_{Pl}$, in the model. The vacuum expectation
values of sneutrinos should be tiny in order that the model works. Some decay
processes of superparticles into acceleron and sterile neutrino are also
discussed in the model.


title: Spin-Orbit Correlations and Single-Spin Asymmetries

abstract:
  Several examples for the role of orbital angular momentum and spin-orbit
correlations in hadron structure are discussed.


title:
Least squares volatility change point estimation for partially observed
  diffusion processes

abstract:
  A one dimensional diffusion process $X=\{X_t, 0\leq t \leq T\}$, with drift
$b(x)$ and diffusion coefficient $\sigma(\theta, x)=\sqrt{\theta} \sigma(x)$
known up to $\theta>0$, is supposed to switch volatility regime at some point
$t^*\in (0,T)$. On the basis of discrete time observations from $X$, the
problem is the one of estimating the instant of change in the volatility
structure $t^*$ as well as the two values of $\theta$, say $\theta_1$ and
$\theta_2$, before and after the change point. It is assumed that the sampling
occurs at regularly spaced times intervals of length $\Delta_n$ with
$n\Delta_n=T$. To work out our statistical problem we use a least squares
approach. Consistency, rates of convergence and distributional results of the
estimators are presented under an high frequency scheme. We also study the case
of a diffusion process with unknown drift and unknown volatility but constant.


title:
Structure of the string link concordance group and Hirzebruch-type
  invariants

abstract:
  We employ Hirzebruch-type invariants obtained from iterated p-covers to
investigate concordance of links and string links. We show that the invariants
naturally give various group homomorphisms of the string link concordance group
into L-groups over number fields. We also obtain homomorphisms of successive
quotients of the Cochran-Orr-Teichner filtration. As an application we show
that the kernel of Harvey's $\rho_n$-invariant is large enough to contain a
subgroup with infinite rank abelianization, modulo local knots. As another
application, we show that recently discovered nontrivial 2-torsion examples of
iterated Bing doubles lying at an arbitrary depth of the Cochran-Orr-Teichner
filtration are independent over $\Z_2$ as links, in an appropriate sense. We
also construct similar examples of infinite order links which are independent
over $\Z$.


title: Double prism evanescent mode experiment: superluminal photons?

abstract:
  A critique on the interpretation of the double prism experiment on the
evanescent microwave modes (arXiv:0708.0681) is presented. It is argued that
these experiments do not give any evidence of superluminal photons. A physical
mechanism based on the inhomogeneous waves of classical electromagnetic fields
is proposed.


title: Local gating of a graphene Hall bar by graphene side gates

abstract:
  We have investigated the magnetotransport properties of a single-layer
graphene Hall bar with additional graphene side gates. The side gating in the
absence of a magnetic field can be modeled by considering two parallel
conducting channels within the Hall bar. This results in an average penetration
depth of the side gate created field of approx. 90 nm. The side gates are also
effective in the quantum Hall regime, and allow to modify the longitudinal and
Hall resistances.


title: New method for extracting quasi-bound states from the continuum

abstract:
  A new parameter-free method is proposed for treatment of single-particle
resonances in the real-energy continuum shell model. This method yields
quasi-bound states embedded in the continuum which provide a natural
generalization of weakly bound single-particle states.


title: Double Fell bundles over discrete double groupoids with folding

abstract:
  In this paper we construct the notions of double Fell bundle and double
C*-category for possible future use as tools to describe noncommutative spaces,
in particular in finite dimensions. We identify the algebra of sections of a
double Fell line bundle over a discrete double groupoid with folding with the
convolution algebra of the latter. This turns out to be what one might call a
double C*-algebra. We generalise the Gelfand-Naimark-Segal construction to
double C*-categories and we form the dual category for a saturated double Fell
bundle using the Tomita-Takesaki involution.


title: Cycle structures of autotopisms of the Latin squares of order up to 11

abstract:
  The cycle structure of a Latin square autotopism
$\Theta=(\alpha,\beta,\gamma)$ is the triple
$(\mathbf{l}_{\alpha},\mathbf{l}_{\beta},\mathbf{l}_{\gamma})$, where
$\mathbf{l}_{\delta}$ is the cycle structure of $\delta$, for all
$\delta\in\{\alpha,\beta,\gamma\}$. In this paper we study some properties of
these cycle structures and, as a consequence, we give a classification of all
autotopisms of the Latin squares of order up to 11.


title:
Outflow or galactic wind: The fate of ionized gas in the halos of dwarf
  galaxies

abstract:
  Context: H\alpha images of star bursting irregular galaxies reveal a large
amount of extended ionized gas structures, in some cases at kpc-distance away
from any place of current star forming activity. A kinematic analysis of
especially the faint structures in the halo of dwarf galaxies allows insights
into the properties and the origin of this gas component. This is important for
the chemical evolution of galaxies, the enrichment of the intergalactic medium,
and for the understanding of the formation of galaxies in the early universe.
  Aims: We want to investigate whether the ionized gas detected in two
irregular dwarf galaxies (NGC 2366 and NGC 4861) stays gravitationally bound to
the host galaxy or can escape from it by becoming a freely flowing wind.
  Methods: Very deep H\alpha images of NGC 2366 and NGC 4861 were obtained to
detect and catalog both small and large scale ionized gas structures down to
very low surface brightnesses. Subsequently, high-resolution long-slit echelle
spectroscopy of the H\alpha line was performed for a detailed kinematic
analysis of the most prominent filaments and shells. To calculate the escape
velocity of both galaxies and to compare it with the derived expansion
velocities of the detected filaments and shells, we used dark matter halo
models.
  Results: We detected a huge amount of both small scale (up to a few hundred
pc) and large scale (about 1-2 kpc of diameter or length) ionized gas
structures on our H\alpha images. Many of the fainter ones are new detections.
The echelle spectra reveal outflows and expanding bubbles/shells with
velocities between 20 and 110 km/s. Several of these structures are in
accordance with filaments in the H\alpha images. A comparison with the escape
velocities of the galaxies derived from the NFW dark matter halo model shows
that all gas features stay gravitationally bound.


title:
A Unified Approach to Stochastic Evolution Equations Using the Skorokhod
  Integral

abstract:
  We study stochastic evolution equations driven by Gaussian noise. The key
features of the model are that the operators in the deterministic and
stochastic parts can have the same order and the noise can be time-only,
space-only, or space-time. Even the simplest equations of this kind do not have
a square-integrable solution and must be solved in special weighted spaces. We
demonstrate that the Cameron-Martin version of the Wiener chaos decomposition
leads to natural weights and a natural replacement of the square integrability
condition.


title:
Molecular Dynamics Simulation of the Hydrogen Isotope Sputtering of
  Graphite

abstract:
  We used a molecular dynamics simulation with the modified Brenner reactive
empirical bond order potential to investigate the erosion of a graphite surface
due to the incidence of hydrogen, deuterium, and tritium atoms. Incident
particles cause pressure on the graphite surface, and the chemical bond between
graphene layers then generates heat to erode the graphite surface. We evaluated
the speed of surface destruction by calculating the pseudo-radial distribution
function. The speed of surface destruction due to incident hydrogen isotopes
was higher than that due to hydrogen atoms. The surface destruction increased
exponentially and its decay time constant was a power function of the incident
energy. We measured the erosion yield, which indicated a steady state for the
graphite erosion. The erosion yield flux in the steady state increased linearly
with the incident energy. The erosion yield flux was almost independent of the
type of incident particle, and the erosion yield start time was smaller for
hydrogen isotopes than for hydrogen atoms.


title:
Minimal surfaces in sub-Riemannian manifolds and structure of their
  singular sets in the (2,3) case

abstract:
  We study minimal surfaces in generic sub-Riemannian manifolds with
sub-Riemannian structures of co-rank one. These surfaces can be defined as the
critical points of the so-called {\it horizontal} area functional associated to
the canonical {\it horizontal} area form. We derive the intrinsic equation in
the general case and then consider in greater detail 2-dimensional surfaces in
contact manifolds of dimension 3. We show that in this case minimal surfaces
are projections of a special class of 2-dimensional surfaces in the horizontal
spherical bundle over the base manifold. Generic singularities of minimal
surfaces turn out the singularities of this projection, and we give a complete
local classification of them. We illustrate our results by examples in the
Heisenberg group and the group of roto-translations


title: The Groebner basis of the ideal of vanishing polynomials

abstract:
  We construct an explicit minimal strong Groebner basis of the ideal of
vanishing polynomials in the polynomial ring over Z/m for m>=2. The proof is
done in a purely combinatorial way. It is a remarkable fact that the
constructed Groebner basis is independent of the monomial order and that the
set of leading terms of the constructed Groebner basis is unique, up to
multiplication by units. We also present a fast algorithm to compute reduced
normal forms, and furthermore, we give a recursive algorithm for building a
Groebner basis in Z/m[x_1,x_2,...,x_n] along the prime factorization of m. The
obtained results are not only of mathematical interest but have immediate
applications in formal verification of data paths for microelectronic
systems-on-chip.


title: Choice and Regularity: Common Consequences in Logic

abstract:
  It is well-known that Choice and Regularity are independent of each other but
have important common consequences of logical character (reflection principles,
representations of classes by sets, etc.). We explain this phenomenon by
isolating their "intersection", a principle (called here Best-Foundedness)
which is consistent with the negations of both axioms but implies all these
consequences. Then we study relationships between these consequences (and near
principles) in detail. Finally, we consider some arguments related to truth of
various principles in set theory, especially arguments concerning the
interpretability strength.


title: H2 Double Ionization with Few-Cycle Laser Pulses

abstract:
  The temporal dynamics of double ionization of H2 has been investigated both
experimentally and theoretically with few-cycle laser pulses. The main
observables are the proton spectra associated to the H^+ + H^+ fragmentation
channel. The model is based on the time-dependent Schr\"odinger equation and
treats on the same level the electronic and nuclear coordinates. Therefore it
allows to follow the ultrafast nuclear dynamics as a function of the laser
pulse duration, carrier-envelope phase offset and peak intensity. We mainly
report results in the sequential double ionization regime above 2 10^{14}
W/cm^2. The proton spectra are shifted to higher energies as the pulse duration
is reduced from 40fs down to 10fs. The good agreement between the model
predictions and the experimental data at 10fs permits a theoretical study with
pulse durations down to a few femtoseconds. We demonstrate the very fast
nuclear dynamics of the H2^+ ion for a pulse duration as short as 1fs between
the two ionization events giving respectively H2^+ from H2 and H^+ + H^+ from
H2^+. Carrier-envelope phase offset only plays a significant role for pulse
durations shorter than 4fs. At 10fs, the laser intensity dependence of the
proton spectra is fairly well reproduced by the model.


title:
The spectrum of closed loops of fundamental flux in D=2+1 SU(N) gauge
  theories

abstract:
  We study the closed-string spectrum of SU(N) gauge theories in the
fundamental representation in 2+1 dimensions. We calculate the energies of the
lowest lying ~ 30 states using a large variety of operators characterised by
the quantum numbers of parity and longitudinal momentum. We find that our
results for the ground state are very well approximated by the Nambu-Goto (NG)
predictions even for short strings. For the excited states, we observe
significant deviations from the NG predictions only for very short strings and
they decrease rapidly with increasing string length. Finally, we see that
Nambu-Goto provides a much better description of our results than the effective
string theoretical predictions. We discuss the continuum and large-N limits.


title: Quasi-maximum likelihood estimation of periodic GARCH processes

abstract:
  This paper establishes the strong consistency and asymptotic normality of the
quasi-maximum likelihood estimator (QMLE) for a GARCH process with periodically
time-varying parameters. We first give a necessary and sufficient condition for
the existence of a strictly periodically stationary solution for the periodic
GARCH (P-GARCH) equation. As a result, it is shown that the moment of some
positive order of the P-GARCH solution is finite, under which we prove the
strong consistency and asymptotic normality (CAN) of the QMLE without any
condition on the moments of the underlying process.


title: On some probabilistic properties of periodic GARCH processes

abstract:
  This paper examines some probabilistic properties of the class of periodic
GARCH processes (PGARCH) which feature periodicity in conditional
heteroskedasticity. In these models, the parameters are allowed to switch
between different regimes, so that their structure shares many properties with
periodic ARMA process (PARMA). We examine the strict and second order periodic
stationarities, the existence of higher-order moments, the covariance
structure, the geometric ergodicity and -mixing of the PGARCH(p,q) process
under general and tractable assumptions. Some examples are proposed to
illustrate the various concepts.


title: Precise dipole moment and quadrupole coupling constants of benzonitrile

abstract:
  We have performed Fourier transform microwave spectroscopy of benzonitrile,
without and with applied electric fields. From the field-free
hyperfine-resolved microwave transitions we simultaneously derive accurate
values for the rotational constants, centrifugal distortion constants, and
nitrogen nuclear quadrupole coupling constants of benzonitrile. By measuring
the Stark shift of selected hyperfine transitions the electric dipole moment of
benzonitrile is determined to $\mu=\mu_a=4.5152 (68)$ D.


title: Chromomagnetic Instability and Gluonic Phase at Nonzero Temperature

abstract:
  We describe the results of recent studies of a chromomagnetic instability and
a gluonic phase in neutral two-flavor quark matter at nonzero temperature.


title: Blistering of viscoelastic filaments

abstract:
  When a dilute polymer solution experiences capillary thinning, it forms an
almost uniformly cylindrical thread, which we study experimentally. In the last
stages of thinning, when polymers have become fully stretched, the filament
becomes prone to instabilities, of which we describe two: A novel "breathing"
instability, originating from the edge of the filament, and a sinusoidal
instability in the interior, which ultimately gives rise to a "blistering"
pattern of beads on the filament. We describe the linear instability with a
spatial resolution of 80 nm in the disturbance amplitude. For sufficiently high
polymer concentrations, the filament eventually separates out into a "solid"
phase of entangled polymers, connected by fluid beads. A solid polymer fiber of
about 100 nanometer thickness remains, which is essentially permanent.


title:
Hodge Theory for G2-manifolds: Intermediate Jacobians and Abel-Jacobi
  maps

abstract:
  We study the moduli space of torsion-free G2-structures on a fixed compact
manifold, and define its associated universal intermediate Jacobian J. We
define the Yukawa coupling and relate it to a natural pseudo-Kahler structure
on J. We consider natural Chern-Simons type functionals, whose critical points
give associative and coassociative cycles (calibrated submanifolds coupled with
Yang-Mills connections), and also deformed Donaldson-Thomas connections. We
show that the moduli spaces of these structures can be isotropically immersed
in J by means of G2-analogues of Abel-Jacobi maps.


title: Time reparameterization in Bianchi type I spinor cosmology

abstract:
  The problem of time reparameterization is addressed at both the classical and
quantum levels in a Bianchi-I universe in which the matter source is a massive
Dirac spinor field. We take the scale factors of the metric as the intrinsic
time and their conjugate momenta as the extrinsic time. A scalar character of
the spinor field is identified as a representation of the extrinsic time. The
construction of the field equations and quantization of the model is achieved
by solving the Hamiltonian constraint after time identification has been dealt
with. This procedure leads to a true Hamiltonian whose exact solutions for the
above choices of time are presented


title:
Simulated Annealing: Rigorous finite-time guarantees for optimization on
  continuous domains

abstract:
  Simulated annealing is a popular method for approaching the solution of a
global optimization problem. Existing results on its performance apply to
discrete combinatorial optimization where the optimization variables can assume
only a finite set of possible values. We introduce a new general formulation of
simulated annealing which allows one to guarantee finite-time performance in
the optimization of functions of continuous variables. The results hold
universally for any optimization problem on a bounded domain and establish a
connection between simulated annealing and up-to-date theory of convergence of
Markov chain Monte Carlo methods on continuous domains. This work is inspired
by the concept of finite-time learning with known accuracy and confidence
developed in statistical learning theory.