title: Multistep kinetic self-assembly of DNA-coated colloids

abstract:
  Self-assembly is traditionally described as the process through which an
initially disordered system relaxes towards an equilibrium ordered phase only
driven by local interactions between its building blocks. However, This
definition is too restrictive. Nature itself provides examples of amorphous,
yet functional, materials assembled upon kinetically arresting the pathway
towards the ground state. Kinetic self-assembly is intrinsically more flexible
and reliable than its equilibrium counterpart, allowing control over the
morphology of the final phase by tuning both the interactions and the
thermodynamic pathway leading to kinetic arrest. Here we propose strategies to
direct the gelation of two-component colloidal mixtures by sequentially
activating selective interspecies and intra-species interactions. We
investigate morphological changes in the structure of the arrested phases by
means of event driven molecular dynamics (MD) simulations and experimentally
using DNA-coated colloids (DNACCs). Our approach can be exploited to finely
tune the morphology of multicomponent nano- or micro-porous materials with
possible applications in hybrid photovoltaics, photonics and drug delivery.


title: Wormholes Threaded by Chiral Fields

abstract:
  We consider Lorentzian wormholes with a phantom field and chiral matter
fields. The chiral fields are described by the non-linear sigma model with or
without a Skyrme term. When the gravitational coupling of the chiral fields is
increased, the wormhole geometry changes. The single throat is replaced by a
double throat with a belly inbetween. For a maximal value of the coupling, the
radii of both throats reach zero. Then the interior part pinches off, leaving a
closed universe and two (asymptotically) flat spaces. A stability analysis
shows that all wormholes threaded by chiral fields inherit the instability of
the Ellis wormhole.


title: Balance Laws in Micromorphic Elasticity

abstract:
  We derive the Eshelby stress tensor, the angular momentum tensor and the
dilatational vector flux for micromorphic elasticity. We give the corresponding
balance laws and the J, L, and M integrals. Also we discuss when the balance
laws become conservation laws.


title: Integration of PDEs by differential geometric means

abstract:
  We use Vessiot theory and exterior calculus to solve partial differential
equations(PDEs) of the type uyy = F(x, y,u,ux,uy,uxx,uxy) and associated
evolution equations. These equations are represented by the Vessiot
distribution of vector fields. We develop and apply an algorithm to find the
largest integrable sub-distributions and hence solutions of the PDEs. We then
apply the integrating factor technique [19] to integrate this integrable
Vessiot sub-distribution. The method is successfully applied to a large class
of linear and non-linear PDEs.


title:
Observations of intensity fluctuations attributed to granulation and
  faculae on Sun-like stars from the Kepler mission

abstract:
  Sun-like stars show intensity fluctuations on a number of time scales due to
various physical phenomena on their surfaces. These phenomena can convincingly
be studied in the frequency spectra of these stars - while the strongest
signatures usually originate from spots, granulation and p-mode oscillations,
it has also been suggested that the frequency spectrum of the Sun contains a
signature of faculae.
  We have analyzed three stars observed for 13 months in short cadence (58.84
seconds sampling) by the Kepler mission. The frequency spectra of all three
stars, as for the Sun, contain signatures that we can attribute to granulation,
faculae, and p-mode oscillations.
  The temporal variability of the signatures attributed to granulation, faculae
and p-mode oscillations were analyzed and the analysis indicates a periodic
variability in the granulation and faculae signatures - comparable to what is
seen in the Sun.


title: Spin-cube Models of Quantum Gravity

abstract:
  We study the state-sum models of quantum gravity based on a representation
2-category of the Poincare 2-group. We call them spin-cube models, since they
are categorical generalizations of spin-foam models. A spin-cube state sum can
be considered as a path integral for a constrained 2-BF theory, and depending
on how the constraints are imposed, a spin-cube state sum can be reduced to a
path integral for the area-Regge model with the edge-length constraints, or to
a path integral for the Regge model. We also show that the effective actions
for these spin-cube models have the correct classical limit.


title:
The Importance of Clipping in Neurocontrol by Direct Gradient Descent on
  the Cost-to-Go Function and in Adaptive Dynamic Programming

abstract:
  In adaptive dynamic programming, neurocontrol and reinforcement learning, the
objective is for an agent to learn to choose actions so as to minimise a total
cost function. In this paper we show that when discretized time is used to
model the motion of the agent, it can be very important to do "clipping" on the
motion of the agent in the final time step of the trajectory. By clipping we
mean that the final time step of the trajectory is to be truncated such that
the agent stops exactly at the first terminal state reached, and no distance
further. We demonstrate that when clipping is omitted, learning performance can
fail to reach the optimum; and when clipping is done properly, learning
performance can improve significantly.
  The clipping problem we describe affects algorithms which use explicit
derivatives of the model functions of the environment to calculate a learning
gradient. These include Backpropagation Through Time for Control, and methods
based on Dual Heuristic Dynamic Programming. However the clipping problem does
not significantly affect methods based on Heuristic Dynamic Programming,
Temporal Differences or Policy Gradient Learning algorithms. Similarly, the
clipping problem does not affect fixed-length finite-horizon problems.


title:
The representation zeta function of a FAb compact p-adic Lie group
  vanishes at -2

abstract:
  Let G by compact p-adic Lie group and suppose that G is FAb, i.e., that
H/[H,H] is finite for every open subgroup H of G. The representation zeta
function Z(G,s) encodes the distribution of continuous irreducible complex
characters of G. Here s denotes a complex variable and Z(G,s) is defined as the
Dirichlet generating function whose nth coefficient is equal to the number of
irreducible characters of G of degree n. For p greater than 2 it is known that
Z(G,s) defines a meromorphic function on the complex plane.
  Wedderburn's structure theorem for semisimple algebras implies that ZG,-2) =
|G| for finite G. We complement this classic result by proving that Z(G,-2) = 0
for infinite G, assuming that p is greater than 2.


title:
Decay properties of the Hardy-Littlewood-Sobolev systems of the
  Lane-Emden type

abstract:
  In this paper, we study the asymptotic behavior of positive solutions of the
nonlinear differential systems of Lane-Emden type $2k$-order equations
$$\{{array}{l}
  (-\Delta)^k u=v^q,u>0 \quad in ~R^n,
  (-\Delta)^k v=u^p,v>0 \quad in ~R^n,
  {array}. $$ and the Hardy-Littlewood-Sobolev (HLS) type system of nonlinear
equations $$ \{{array}{l}
u(x)=\displaystyle\int_{R^n}\frac{v^q(y)dy}{|x-y|^{n-\alpha}},u>0 \quad in
~R^n, v(x)=\displaystyle\int_{R^n}\frac{u^p(y)dy}{|x-y|^{n-\alpha}},u>0 \quad
in ~R^n.
  {array}. $$ Such an integral system is related to the study the extremal
functions of the HLS inequality. We point out that the bounded solutions $u,v$
converge to zero either with the fast decay rates or with the slow decay rates
when $|x| \to \infty$ under some assumptions. In addition, we also find a
criterion to distinguish the fast and the slow decay rates: if $u,v$ are the
integrable solutions (i.e. $(u,v) \in L^{r_0}(R^n) \times L^{s_0}(R^n)$), then
they decay fast; if the bounded solutions $u,v$ are not the integrable
solutions (i.e. $(u,v) \not\in L^{r_0}(R^n) \times L^{s_0}(R^n)$), then they
decay almost slowly. Here, for the HLS type system,
$r_0=\frac{n(pq-1)}{\alpha(q+1)}$, $s_0=\frac{n(pq-1)}{\alpha(p+1)}$; and for
the Lane-Emden type system, $r_0,s_0$ are still the forms above where $\alpha$
is replaced by $2k$.


title:
On Neumann and oblique derivatives boundary conditions for nonlocal
  elliptic equations

abstract:
  Inspired by the penalization of the domain approach of Lions & Sznitman, we
give a sense to Neumann and oblique derivatives boundary value problems for
nonlocal, possibly degenerate elliptic equations. Two different cases are
considered: (i) homogeneous Neumann boundary conditions in convex, possibly
non-smooth and unbounded domains, and (ii) general oblique derivatives boundary
conditions in smooth, bounded, and possibly non-convex domains. In each case we
give apropriate definitions of viscosity solutions and prove uniqueness of
solutions of the corresponding boundary value problems. We prove that these
boundary value problems arise in the penalization of the domain limit from
whole space problems and obtain as a corollary the existence of solutions of
these problems.


title: SKT and Tamed Symplectic structures on solvmanifolds

abstract:
  We study the existence of strong K\"ahler with torsion (SKT) metrics and of
symplectic forms taming invariant complex structures $J$ on solvmanifolds
$G/\Gamma$ providing some negative results for some classes of solvmanifolds.
In particular, we show that if either $J$ is invariant under the action of a
nilpotent complement of the nilradical of $G$ or $J$ is abelian or $G$ is
almost abelian (not of type (I)), then the solvmanifold $G/\Gamma$ cannot admit
any symplectic form taming the complex structure $J$, unless $G/\Gamma$ is
K\"ahler. As a consequence, we show that the family of non-K\"ahler complex
manifolds constructed by Oeljeklaus and Toma cannot admit any symplectic form
taming the complex structure.


title: Life after eruption - II. The eclipsing old nova V728 Scorpii

abstract:
  The old nova V728 Sco has been recently recovered via photometric and
spectroscopic observations, 150 years after the nova eruption. The spectral
properties pointed to a high-inclination system with a comparatively low
mass-transfer rate. In this paper we show that the object is an eclipsing
system with an orbital period of 3.32 h. It has enhanced long-term variability
that can be interpreted as 'stunted' dwarf-nova-type outbursts. Using the
ingress and egress times of the eclipsed components we calculate the radius of
the central object. The latter turns out to be significantly larger than a
white dwarf and we identify it with a hot inner disc. The implications for
models on the behaviour of post-novae are discussed.


title:
Multiple recurrence for non-commuting transformations along rationally
  independent polynomials

abstract:
  We prove a multiple recurrence result for arbitrary measure-preserving
transformations along polynomials in two variables of the form $m+p_i(n)$, with
rationally independent $p_i$'s with zero constant term. This is in contrast to
the single variable case, in which even double recurrence fails unless the
transformations generate a virtually nilpotent group. The proof involves
reduction to nilfactors and an equidistribution result on nilmanifolds.


title:
Hylleraas-configuration-interaction analysis of the low-lying states in
  the three-electron Li atom and Be+ ion

abstract:
  The total energies of twenty eight bound S-, P-, D-, F-, G-, H-, and I-states
in the three-electron systems Li atom and Be+ ion, respectively, are determined
with the use of the Configuration Interaction (CI) with Slater orbitals and L-S
eigenfunctions, and the Hylleraas-configuration-interaction (Hy-CI) methods. We
discuss the construction and selection of the configurations in the wave
functions, optimization of the orbital exponents and advanced computational
techniques. Finally, we have developed a very effective procedure which allows
one to determine the energies of the excited states in three-electron atoms and
ions to high accuracy by using compact wave functions. For the ground and low
lying excited states our best accuracy with the Hy-CI method was approximately
1.10-6 a.u. and 1.10-4 a.u. for other excited states. Analogous accuracy of the
CI method is substantially lower approximately 1.10-3 a.u. Many of the
rotationally excited (bound) states in the three-electron Li atom and Be+ ion
have never been evaluated to such an accuracy.


title: Lifting Hamiltonian loops to isotopies in fibrations

abstract:
  Let $G$ be a Lie group, $H$ a closed subgroup and $M$ the homogeneous space
$G/H$. Each representation $\Psi$ of $H$ determines a $G$-equivariant principal
bundle ${\mathcal P}$ on $M$ endowed with a $G$-invariant connection. We
consider subgroups ${\mathcal G}$ of the diffeomorphism group ${\rm Diff}(M)$,
such that, each vector field $Z\in{\rm Lie}({\mathcal G})$ admits a lift to a
preserving connection vector field on ${\mathcal P}$. We prove that
$#\,\pi_1({\mathcal G})\geq #\,\Psi(Z(G))$. This relation is applicable to
subgroups ${\mathcal G}$ of the Hamiltonian groups of the flag varieties of a
semisimple group $G$.
  Let $M_{\Delta}$ be the toric manifold determined by the Delzant polytope
$\Delta$. We put $\varphi_{\bf b}$ for the the loop in the Hamiltonian group of
$M_{\Delta}$ defined by the lattice vector ${\bf b}$. We give a sufficient
condition, in terms of the mass center of $\Delta$, for the loops $\varphi_{\bf
b}$ and $\varphi_{\bf\tilde b}$ to be homotopically inequivalent.


title: Molecular theory of anomalous diffusion

abstract:
  We present a Master Equation formulation based on a Markovian random walk
model that exhibits sub-diffusion, classical diffusion and super-diffusion as a
function of a single parameter. The non-classical diffusive behavior is
generated by allowing for interactions between a population of walkers. At the
macroscopic level, this gives rise to a nonlinear Fokker-Planck equation. The
diffusive behavior is reflected not only in the mean-squared displacement
($<r^2(t)>\sim t^{\gamma}$ with $0 <\gamma \leq 1.5$) but also in the existence
of self-similar scaling solutions of the Fokker-Planck equation. We give a
physical interpretation of sub- and super-diffusion in terms of the attractive
and repulsive interactions between the diffusing particles and we discuss
analytically the limiting values of the exponent $\gamma$. Simulations based on
the Master Equation are shown to be in agreement with the analytical solutions
of the nonlinear Fokker-Planck equation in all three diffusion regimes.


title: The divergence of the special linear group over a function ring

abstract:
  We compute the divergence of the finitely generated group SLn(O_S), where S
is a finite set of valuations of a function field, and O_S is the corresponding
ring of S-integer points. As an application, we deduce that all its asymptotic
cones are without cut-points.


title:
Predictivity of models with spontaneously broken non-Abelian discrete
  flavor symmetries

abstract:
  In a class of supersymmetric flavor models predictions are based on residual
symmetries of some subsectors of the theory such as those of the charged
leptons and neutrinos. However, the vacuum expectation values of the so-called
flavon fields generally modify the K\"ahler potential of the setting, thus
changing the predictions. We derive simple analytic formulae that allow us to
understand the impact of these corrections on the predictions for the masses
and mixing parameters. Furthermore, we discuss the effects on the vacuum
alignment and on flavor changing neutral currents. Our results can also be
applied to non--supersymmetric flavor models.


title: Instantons in six dimensions and twistors

abstract:
  Recently, conformal field theories in six dimensions were discussed from the
twistorial point of view. In particular, it was demonstrated that the twistor
transform between chiral zero-rest-mass fields and cohomology classes on
twistor space can be generalized from four to six dimensions. On the other
hand, the possibility of generalizing the correspondence between instanton
gauge fields and holomorphic bundles over twistor space is questionable. It was
shown by Saemann and Wolf that holomorphic line bundles over the canonical
twistor space Tw(X) (defined as a bundle of almost complex structures over the
six-dimensional manifold X) correspond to pure-gauge Maxwell potentials, i.e.
the twistor transform fails. On the example of X=CP^3 we show that there exists
a twistor correspondence between Abelian or non-Abelian Yang-Mills instantons
on CP^3 and holomorphic bundles over complex submanifolds of Tw(CP^3), but it
is not so efficient as in the four-dimensional case because the twistor
transform does not parametrize instantons by unconstrained holomorphic data as
it does in four dimensions.


title:
Measurements of the Lambda_b0 -> J/psi Lambda decay amplitudes and the
  Lambda_b0 polarisation in pp collisions at sqrt(s) = 7 TeV

abstract:
  An angular analysis of Lambda_b0 -> J/psi Lambda decays is performed using a
data sample corresponding to 1.0 fb^{-1} collected in pp collisions at sqrt(s)
= 7 TeV with the LHCb detector at the LHC. A parity violating asymmetry
parameter characterising the Lambda_b0 -> J/psi Lambda decay of 0.05 +/- 0.17
+/- 0.07 and a Lambda_b0 transverse production polarisation of 0.06 +/- 0.07
+/- 0.02 are measured, where the first uncertainty is statistical and the
second systematic.


title: On special quadratic birational transformations of a projective space

abstract:
  A birational map from a projective space onto a not too much singular
projective variety with a single irreducible non-singular base locus scheme
(special birational transformation) is a rare enough phenomenon to allow
meaningful and concise classification results.
  We shall concentrate on transformations defined by quadratic equations onto
some varieties (especially projective hypersurfaces of small degree), where
quite surprisingly the base loci are interesting projective manifolds appearing
in other contexts; for example, exceptions for adjunction theory, small degree
or small codimensional manifolds, Severi or more generally homogeneous
varieties.
  In particular, we shall classify: quadro-quadric transformations into a
quadric hypersurface; quadro-cubic transformations into a del Pezzo variety;
transformations whose base locus (scheme) has dimension at most three.


title:
Centrality dependence of inclusive prompt photon production in d+Au,
  Au+Au, p+Pb, and Pb+Pb collisions

abstract:
  We calculate the centrality dependence of the midrapidity nuclear
modification for inclusive prompt photon production in d+Au and Au+Au
collisions at RHIC and in p+Pb and Pb+Pb collisions at the LHC. Our results,
using the recent spatially dependent nuclear PDF set EPS09s, are consistent
with the existing high-pT data from the PHENIX and CMS collaborations. The good
agreement even in the case of nucleus+nucleus collisions suggests that the
high-pT direct photon production is not significantly altered by the strongly
interacting medium produced in such collisions. We find the centrality
dependence of the nuclear modifications generally rather weak but perhaps
measurable at low pT.


title:
Simulating Raman Spectra using molecular dynamics, and identification of
  high-pressure phases III and IV in hydrogen

abstract:
  We present a technique for extracting Raman intensities from ab initio
molecular dynamics (MD) simulations at high temperature. The method is applied
to the highly anharmonic case of dense hydrogen up to 500 K for pressures
ranging from 180 GPa to 300 GPa. On heating or pressurizing we find first-order
phase transitions at the experimental conditions of the phase III - IV
boundary. Direct comparison of Raman vibrons with experiment provides excellent
discrimination between subtly different structures, found in MD. We find
candidate structures whose Raman spectra are in good agreement with experiment.
The new phase obtained in high temperature simulations adopts a dynamic, simple
hexagonal structure with three layer types: freely rotating hydrogen molecules,
static hexagonal trimers and rotating hexagonal trimers. We show that
previously calculated structures for phase IV are inconsistent with experiment,
and their appearance in simulation is due to finite size effects.


title:
Matrix product states and variational methods applied to critical
  quantum field theory

abstract:
  We study the second-order quantum phase-transition of massive real scalar
field theory with a quartic interaction ($\phi^4$ theory) in (1+1) dimensions
on an infinite spatial lattice using matrix product states (MPS). We introduce
and apply a naive variational conjugate gradient method, based on the
time-dependent variational principle (TDVP) for imaginary time, to obtain
approximate ground states, using a related ansatz for excitations to calculate
the particle and soliton masses and to obtain the spectral density. We also
estimate the central charge using finite-entanglement scaling. Our value for
the critical parameter agrees well with recent Monte Carlo results, improving
on an earlier study which used the related DMRG method, verifying that these
techniques are well-suited to studying critical field systems. We also obtain
critical exponents that agree, as expected, with those of the transverse Ising
model. Additionally, we treat the special case of uniform product states (mean
field theory) separately, showing that they may be used to investigate
non-critical quantum field theories under certain conditions.


title: Quarkonium Resonance Model of the 125 GeV Boson

abstract:
  A quarkonium model of the recently discovered X boson at 125 GeV is
investigated. Two isosinglet $J^{PC}=0^{-+}$ resonances $\zeta$ and $\zeta'$
mix and their masses are determined by the masses of the bottomonium and
toponium eigenstates. This mixing is enhanced by the non-perturbative gluon
interaction produced by an axial $U_A(1)$ anomaly. The resonance $\zeta$ is
identified with the 125 GeV boson X, while the heavier $\zeta'$ resonance has a
mass 230 GeV. We assess the most recent data for the decay mode $X\rightarrow
ZZ^*\rightarrow$ 4 leptons with a critical discussion of the determination of
the parity of the $X$ boson.


title:
On the non-uniqueness problem of the covariant Dirac theory and the
  spin-rotation coupling

abstract:
  Gorbatenko & Neznamov [arXiv:1301.7599] recently claimed the absence of the
title problem. In this paper, the reason for that problem is reexplained by
using the notions of a unitary transformation and of the mean value of an
operator, invoked by them. Their arguments actually aim at proving the
uniqueness of a particular prescription for solving this problem. But that
prescription is again shown non-unique. Two Hamiltonians in the same reference
frame in a Minkowski spacetime, only one of them including the spin-rotation
coupling term, are proved to be physically non-equivalent. This confirms that
the reality of that coupling should be checked experimentally.


title: Design of a novel electrostatic ion storage ring at KACST

abstract:
  A new electrostatic storage ring for beams at energies up to 30keV.q is
currently under development at the National Centre for Mathematics and Physics
(NCMP), King Abdulaziz City for Science and Technology (KACST). The ring design
is based on the existing electrostatic storage rings, but stretches
significantly beyond them in that it shall form the core of a unique flexible
experimental facility at KACST. The lattice of this ring has been designed in a
way that enables the use of state-of-the-art experimental methods to study
electron-ion, laser-ion, and ion-neutral beams interactions. The lattice design
also allows for a future upgrade of the ring to a double storage ring structure
that would enable ion-ion beam interactions to be performed. In this paper, we
present the design of this ring with a focus on beam dynamics calculations for
the 7o single-bend racetrack layout. The study is principally based on the
SIMION8 program. We complemented this study further by using purpose-written
routine and MAD-X simulation code. An in-depth investigation into beam
stability under consideration of non-linear field components in the
electrostatic optical elements, is presented. Finally, different working points
and stability regions are discussed.


title:
PENCIL: Towards a Platform-Neutral Compute Intermediate Language for
  DSLs

abstract:
  We motivate the design and implementation of a platform-neutral compute
intermediate language (PENCIL) for productive and performance-portable
accelerator programming.


title:
A dispersion and norm preserving finite difference scheme with
  transparent boundary conditions for the Dirac equation in (1+1)D

abstract:
  A finite difference scheme is presented for the Dirac equation in (1+1)D. It
can handle space- and time-dependent mass and potential terms and utilizes
exact discrete transparent boundary conditions (DTBCs). Based on a space- and
time-staggered leap-frog scheme it avoids fermion doubling and preserves the
dispersion relation of the continuum problem for mass zero (Weyl equation)
exactly. Considering boundary regions, each with a constant mass and potential
term, the associated DTBCs are derived by first applying this finite difference
scheme and then using the Z-transform in the discrete time variable. The
resulting constant coefficient difference equation in space can be solved
exactly on each of the two semi-infinite exterior domains. Admitting only
solutions in $l_2$ which vanish at infinity is equivalent to imposing outgoing
boundary conditions. An inverse Z-transformation leads to exact DTBCs in form
of a convolution in discrete time which suppress spurious reflections at the
boundaries and enforce stability of the whole space-time scheme. An exactly
preserved functional for the norm of the Dirac spinor on the staggered grid is
presented. Simulations of Gaussian wave packets, leaving the computational
domain without reflection, demonstrate the quality of the DTBCs numerically, as
well as the importance of a faithful representation of the energy-momentum
dispersion relation on a grid.


title: Euler Characteristic in Odd Dimensions

abstract:
  It is well known that the Euler characteristic of an odd dimensional compact
manifold is zero. An Euler complex is a combinatorial analogue of a compact
manifold. We present here an elementary proof of the corresponding result for
Euler complexes.


title:
Finding the basic neighborhood in variable range Markov random fields:
  application in SNP association studies

abstract:
  The SNPs (Single Nucleotide Polymorphisms) genotyping platforms are of great
value for gene mapping of complex diseases. Nowadays, the high-density of these
molecular markers enables studies of dependence patterns between loci over the
genome, allowing a simultaneous inference of dependence structure and disease
association. In this paper we propose a method based on the theory of variable
range Markov random fields to estimate the extent of dependence among SNPs
allowing variable windows along the genome. The advantage of this method is
that it allows the simultaneous prediction of dependence and independence
regions among SNPs, without restricting a priori the range of dependence. We
introduce an estimator based on the idea of penalized maximum likelihood to
find the conditional dependence neighborhood of each SNP in the sample and we
prove its consistency. We apply our method to autosomal SNPs genotypic data
with unknown phase in the context of case-control association studies. By
examining rheumatoid arthritis data from the Genetic Analysis Workshop 16
(GAW16), we show the utility of the Markov model under variable range
dependence.


title: Quasi-Dirac neutrinos and solar neutrino data

abstract:
  We present an analysis of the solar neutrino data in the context of a
quasi-Dirac neutrino model in which the lepton mixing matrix is given at tree
level by the tribimaximal matrix. When radiative corrections are taken into
account, new effects in neutrino oscillations, as $\nu_e \to \nu_s$, appear.
This oscillation is constrained by the solar neutrino data. In our analysis, we
have found an allowed region for our two free parameters $\epsilon$ and $m_1$.
The radiative correction, $\epsilon$, can vary approximately from $5\times
10^{-9}$ to $10^{-6}$ and the calculated fourth mass eigenstate, $m_4$, 0.01 eV
to 0.2 eV at 2$\sigma$ level. These results are very similar to the ones
presented in the literature.


title: On the size of Kakeya sets in finite vector spaces

abstract:
  For a finite field GF(q) a Kakeya set K is a subset of GF(q)^n that contains
a line in every direction. This paper derives new upper bounds on the minimum
size of Kakeya sets when q is even.


title: A tournament of order 24 with two disjoint TEQ-retentive sets

abstract:
  Brandt et al. (2013) have recently disproved a conjecture by Schwartz (1990)
by non-constructively showing the existence of a counterexample with about
10^136 alternatives. We provide a concrete counterexample for Schwartz's
conjecture with only 24 alternatives.


title: Affine buildings, tiling systems and higher rank Cuntz-Krieger algebras

abstract:
  To an $r$-dimensional subshift of finite type satisfying certain special
properties we associate a $C^*$-algebra $\cA$. This algebra is a higher rank
version of a Cuntz-Krieger algebra. In particular, it is simple, purely
infinite and nuclear. We study an example: if $\G$ is a group acting freely on
the vertices of an $\wt A_2$ building, with finitely many orbits, and if
$\Omega$ is the boundary of that building, then $C(\Om)\rtimes \G$ is the
algebra associated to a certain two dimensional subshift.


title: Non-commutative lattice modified Gel'fand-Dikii systems

abstract:
  We introduce integrable multicomponent non-commutative lattice systems, which
can be considered as analogs of the modified Gel'fand-Dikii hierarchy. We
present the corresponding systems of Lax pairs and we show directly
multidimensional consistency of these Gel'fand-Dikii type equations. We
demonstrate how the systems can be obtained as periodic reductions of the
non-commutative lattice Kadomtsev-Petviashvilii hierarchy. The geometric
description of the hierarchy in terms of Desargues maps helps to derive
non-isospectral generalization of the non-commutative lattice modified
Gel'fand-Dikii systems. We show also how arbitrary functions of single
arguments appear naturally in our approach when making commutative reductions,
which we illustrate on the non-isospectral non-autonomous versions of the
lattice modified Korteweg-de Vries and Boussinesq systems.


title: Corrections to the Banks-Casher relation with Wilson quarks

abstract:
  The Banks-Casher relation links the spectral density of the Dirac operator
with the existence of a chiral condensate and spontaneous breaking of chiral
symmetry. This relation receives corrections from a finite value of the quark
mass, a finite space-time volume and, if evaluated on a discrete lattice, from
the finite value of the lattice spacing a. We present a status report of a
determination of these corrections for Wilson quarks.


title: Quantum equivalence principle without mass superselection

abstract:
  The standard argument for the validity of Einstein's equivalence principle in
a non-relativistic quantum context involves the application of a mass
superselection rule. It is surprising that the consistency between such an
important principle and quantum mechanics depends crucially on the imposition
of a non-fundamental restriction. The objective of this work is show that,
contrary to what the standard account holds, the compatibility between the
principle of equivalence and quantum mechanics does not depend on the
introduction of such a superselection rule. For this purpose, we consider the
extended Galileo group, in which mass is treated as an operator, and show that
within this scheme superpositions of different masses behave as they should in
order to obey the equivalence principle.


title: On integrals of eigenfunctions over geodesics

abstract:
  If $(M,g)$ is a compact Riemannian surface then the integrals of
$L^2(M)$-normalized eigenfunctions $e_j$ over geodesic segments of fixed length
are uniformly bounded. Also, if $(M,g)$ has negative curvature and $\gamma(t)$
is a geodesic parameterized by arc length, the measures $e_j(\gamma(t))\, dt$
on $\R$ tend to zero in the sense of distributions as the eigenvalue $\la_j\to
\infty$, and so integrals of eigenfunctions over periodic geodesics tend to
zero as $\la_j\to \infty$. The assumption of negative curvature is necessary
for the latter result.


title: A Haagerup Inequality for $\tA_1\times\tA_1$ and $\tA_2$ Buildings

abstract:
  Haagerup's inequality for convolvers on free groups may be interpreted as a
result on $\tA_1$ buildings, i.e. trees. Here are proved analogous inequalities
for discrete groups acting freely on the vertices of $\tA_1\times\tA_1$ and
$\tA_2$ buildings. The results apply in particular to groups of type-rotating
automorphisms acting simply transitively on the vertices of such buildings.
These results provide the first examples of higher rank groups with property
(RD).


title:
The dependence of the stability of hierarchical triple systems on the
  orbital inclination

abstract:
  In this paper we study numerically the effect of the initial mutual orbital
inclination on the stability of hierarchical triple systems with initially
circular orbits. Our aim is to investigate the possibility that the stability
boundary may be independent of the orbital inclination for certain mass ratios.
We integrate numerically the equations of motion of hierarchical triple systems
with initially circular orbits and different orbital configurations. The mass
ratios cover the range from 0.000001 to 1000000 and the initial mutual
inclination angle varies from 0 to 180 degrees. The results from the numerical
simulations show that for hierarchical triple systems with initially circular
orbits and for the mass ratios we used, the initial mutual inclination angle
does affect the stability boundary.


title:
Magnetic Domain Structure of La0.7Sr0.3MnO3 thin-films probed at
  variable temperature with Scanning Electron Microscopy with Polarization
  Analysis

abstract:
  The domain configuration of 50 nm thick La0.7SrMnO3 films has been directly
investigated using scanning electron microscopy with polarization analysis
(SEMPA), with magnetic contrast obtained without the requirement for prior
surface preparation. The large scale domain structure reflects a primarily
four-fold anisotropy, with a small uniaxial component, consistent with
magneto-optic Kerr effect measurements. We also determine the domain transition
profile and find it to be in agreement with previous estimates of the domain
wall width in this material. The temperature dependence of the image contrast
is investigated and compared to superconducting-quantum interference device
magnetometry data. A faster decrease in the SEMPA contrast is revealed, which
can be explained by the technique's extreme surface sensitivity, allowing us to
selectively probe the surface spin polarization which due to the double
exchange mechanism exhibits a distinctly different temperature dependence than
the bulk magnetization.


title: Numerical Methods and Causality in Physics

abstract:
  We discuss physical implications of the explicit method in numerical
analysis. Numerical methods have there own condition for causality, known as
the Courant-Friedrichs-Lewy condition. It is proposed that numerical causality
merges with physical causality as the grid interval size approaches zero. We
discuss the implications of this proposition on the numerical analysis of the
wave equation. We also show that, insisting on physical causality, the
numerical analysis of Schrodinger's equation implies that the minimum space
interval should satisfy $\Delta x \ge a_0 \lambda_c$, where $\lambda_c$ is the
reduced Compton wavelength and $a_0$ is a constant of the order unity.


title: Dissipation and supercurrent fluctuations in a diffusive NS ring

abstract:
  A mesoscopic hybrid Normal/ Superconducting (NS) ring is characterized by a
dense Andreev spectrum with a flux dependent minigap. We measure the linear
response to a high frequency flux, in a wide frequency range, with a multimode
superconducting resonator. We find that the current response contains, beside
the well known dissipation-less Josephson contribution, a large dissipative
component. At high frequency compared to the minigap and low temperature we
find that the dissipation is due to transitions above the minigap. In contrast,
at lower frequency there is range of temperature for which dissipation is
caused predominantly by the relaxation of the Andreev states' population.


title: TeV Astronomy

abstract:
  With the successful realization of the current-generation of ground-based
detectors, TeV Astronomy has entered into a new era. We review recent advances
in VHE astronomy, focusing on the potential of Imaging Atmospheric Cherenkov
Telescopes (IACTs), and highlight astrophysical implications of the results
obtained within recent years.


title:
Study of resonance states of $^{11}$Be with isospectral bound state
  microscopic potential

abstract:
  The theoretical procedure of supersymmetric quantum mechanics (SQM) is
adopted for the first time to study quasi-bound states of a weakly bound
nuclear system using microscopic potential. The density dependent M3Y (DDM3Y)
effective interaction was found earlier to give a satisfactory description of
radioactivity, nuclear matter and scattering. In the present work, we have
generated a two-body potential microscopically in a single folding model using
the DDM3Y effective interaction. From this potential, SQM generated a family of
isospectral potentials for $^{11}$Be ($^{10}$Be + n). We investigated the
5/2$^+$, 3/2$^-$ and 3/2$^+$ resonance states of $^{11}$Be. The experimental
data and the present calculations of excitation energies of the above resonance
states are found to be in good agreement.


title:
Unconventional magnetostructural transition in CoCr2O4 at high magnetic
  fields

abstract:
  The magnetic-field and temperature dependencies of ultrasound propagation and
magnetization of single-crystalline CoCr2O4 have been studied in static and
pulsed magnetic fields up to 14 T and 62 T, respectively. Distinct anomalies
with significant changes in the sound velocity and attenuation are found in
this spinel compound at the onset of long-range incommensurate spiral-spin
order at T_s = 27 K and at the transition from the incommensurate to the
commensurate state at T_l = 14 K, evidencing strong spin-lattice coupling.
While the magnetization evolves gradually with field, steplike increments in
the ultrasound clearly signal a transition into a new magneto-structural state
between 6.2 and 16.5 K and at high magnetic fields. We argue that this is a
high-symmetry phase with only the longitudinal component of the magnetization
being ordered, while the transverse helical component remains disordered. This
phase is metastable in an extended H-T phase space.


title:
Convergence analysis of some multivariate Markov chains using stochastic
  monotonicity

abstract:
  We provide a nonasymptotic analysis of convergence to stationarity for a
collection of Markov chains on multivariate state spaces, from arbitrary
starting points, thereby generalizing results in [Khare and Zhou Ann. Appl.
Probab. 19 (2009) 737-777]. Our examples include the multi-allele Moran model
in population genetics and its variants in community ecology, a generalized
Ehrenfest urn model and variants of the Polya urn model. It is shown that all
these Markov chains are stochastically monotone with respect to an appropriate
partial ordering. Then, using a generalization of the results in [Diaconis,
Khare and Saloff-Coste Sankhya 72 (2010) 45-76] and [Wilson Ann. Appl. Probab.
14 (2004) 274-325] (for univariate totally ordered spaces) to multivariate
partially ordered spaces, we obtain explicit nonasymptotic bounds for the
distance to stationarity from arbitrary starting points. In previous
literature, bounds, if any, were available only from special starting points.
The analysis also works for nonreversible Markov chains, and allows us to
analyze cases of the multi-allele Moran model not considered in [Khare and Zhou
Ann. Appl. Probab. 19 (2009) 737-777].


title: Distributed Community Detection in Dynamic Graphs

abstract:
  Inspired by the increasing interest in self-organizing social opportunistic
networks, we investigate the problem of distributed detection of unknown
communities in dynamic random graphs. As a formal framework, we consider the
dynamic version of the well-studied \emph{Planted Bisection Model}
$\sdG(n,p,q)$ where the node set $[n]$ of the network is partitioned into two
unknown communities and, at every time step, each possible edge $(u,v)$ is
active with probability $p$ if both nodes belong to the same community, while
it is active with probability $q$ (with $q<<p$) otherwise. We also consider a
time-Markovian generalization of this model.
  We propose a distributed protocol based on the popular \emph{Label
Propagation Algorithm} and prove that, when the ratio $p/q$ is larger than
$n^{b}$ (for an arbitrarily small constant $b>0$), the protocol finds the right
"planted" partition in $O(\log n)$ time even when the snapshots of the dynamic
graph are sparse and disconnected (i.e. in the case $p=\Theta(1/n)$).


title:
Accelerated Linear SVM Training with Adaptive Variable Selection
  Frequencies

abstract:
  Support vector machine (SVM) training is an active research area since the
dawn of the method. In recent years there has been increasing interest in
specialized solvers for the important case of linear models. The algorithm
presented by Hsieh et al., probably best known under the name of the
"liblinear" implementation, marks a major breakthrough. The method is analog to
established dual decomposition algorithms for training of non-linear SVMs, but
with greatly reduced computational complexity per update step. This comes at
the cost of not keeping track of the gradient of the objective any more, which
excludes the application of highly developed working set selection algorithms.
We present an algorithmic improvement to this method. We replace uniform
working set selection with an online adaptation of selection frequencies. The
adaptation criterion is inspired by modern second order working set selection
methods. The same mechanism replaces the shrinking heuristic. This novel
technique speeds up training in some cases by more than an order of magnitude.


title: Dualities in modal logic from the point of view of triples

abstract:
  In this paper we show how the theory of monads can be used to deduce in a
uniform manner several duality theorems involving categories of relations on
one side and categories of algebras with homomorphisms preserving only some
operations on the other. Furthermore, we investigate the monoidal structure
induced by Cartesian product on the relational side and show that in some cases
the corresponding operation on the algebraic side represents bimorphisms.


title:
Spin Currents and Spontaneous Magnetization at Twin Boundaries of
  Noncentrosymmetric Superconductors

abstract:
  Twin boundaries are generic crystalline defects in noncentrosymmetric crystal
structures. We study theoretically twin boundaries in time-reversal symmetric
noncentrosymmetric superconductors that admit parity-mixed Cooper pairing. Twin
boundaries support spin currents as a consequence of this parity mixing. If the
singlet and triplet components of the superconducting order parameter are of
comparable magnitude, the superconducting state breaks spontaneously the bulk
time-reversal symmetry locally near the twin boundary. By self-consistently
evaluating the Bogoliubov-de-Gennes equations and the gap functions we find two
distinct phases: First, time-reversal symmetry breaking enhances the spin
currents but does not lead to chiral supercurrents. A secondary phase
transition then triggers a spin magnetization and an orbital supercurrent near
the twin boundary.


title: Transit Node Routing Reconsidered

abstract:
  Transit Node Routing (TNR) is a fast and exact distance oracle for road
networks. We show several new results for TNR. First, we give a surprisingly
simple implementation fully based on Contraction Hierarchies that speeds up
preprocessing by an order of magnitude approaching the time for just finding a
CH (which alone has two orders of magnitude larger query time). We also develop
a very effective purely graph theoretical locality filter without any
compromise in query times. Finally, we show that a specialization to the online
many-to-one (or one-to-many) shortest path further speeds up query time by an
order of magnitude. This variant even has better query time than the fastest
known previous methods which need much more space.


title: Calorimetric study in single crystal of CsFe$_2$As$_2$

abstract:
  We measured resistivity and specific heat of high-quality CsFe$_2$As$_2$
single crystals, which were grown by using a self-flux method. The
CsFe$_2$As$_2$ crystal shows sharp superconducting transition at 1.8 K with the
transition width of 0.1 K. The sharp superconducting transition and pronounced
jump in specific heat indicate high quality of the crystals. Analysis on the
superconducting-state specific heat supports unconventional pairing symmetry in
CsFe$_2$As$_2$.


title: Polynomially convex hulls of singular real manifolds

abstract:
  We obtain local and global results on polynomially convex hulls of Lagrangian
and totally real submanifolds of $C^n$ with self-intersections and open Whitney
umbrella points.


title:
Crystal structure and properties of barium thorate BaThO$_3$ from first
  principles

abstract:
  The phonon spectrum of cubic BaThO$_3$ with the perovskite structure is
calculated from first principles within the density functional theory. The
analysis of unstable modes in the phonon spectrum enables to determine the
symmetry of all possible distorted phases, calculate their energies, and show
that the ground-state structure of barium thorate is $Pbnm$. For this
structure, the static and optical dielectric constants, elastic moduli, heat
capacity, Raman spectra, and the energy band gap in the LDA and $GW$
approximations are calculated. The possibility of the structural phase
transitions in BaThO$_3$ is also discussed.


title: Bifurcations and exceptional points in dipolar Bose-Einstein condensates

abstract:
  Bose-Einstein condensates are described in a mean-field approach by the
nonlinear Gross-Pitaevskii equation and exhibit phenomena of nonlinear
dynamics. The eigenstates can undergo bifurcations in such a way that two or
more eigenvalues and the corresponding wave functions coalesce at critical
values of external parameters. E.g. in condensates without long-range
interactions a stable and an unstable state are created in a tangent
bifurcation when the scattering length of the contact interaction is varied. At
the critical point the coalescing states show the properties of an exceptional
point. In dipolar condensates fingerprints of a pitchfork bifurcation have been
discovered by Rau et al. [Phys. Rev. A, 81:031605(R), 2010]. We present a
method to uncover all states participating in a pitchfork bifurcation, and
investigate in detail the signatures of exceptional points related to
bifurcations in dipolar condensates. For the perturbation by two parameters,
viz. the scattering length and a parameter breaking the cylindrical symmetry of
the harmonic trap, two cases leading to different characteristic eigenvalue and
eigenvector patterns under cyclic variations of the parameters need to be
distinguished. The observed structures resemble those of three coalescing
eigenfunctions obtained by Demange and Graefe [J. Phys. A, 45:025303, 2012]
using perturbation theory for non-Hermitian operators in a linear model.
Furthermore, the splitting of the exceptional point under symmetry breaking in
either two or three branching singularities is examined. Characteristic
features are observed when one, two, or three exceptional points are encircled
simultaneously.


title: Large Deviations for Nonlocal Stochastic Neural Fields

abstract:
  We study the effect of additive noise on integro-differential neural field
equations. In particular, we analyze an Amari-type model driven by a $Q$-Wiener
process and focus on noise-induced transitions and escape. We argue that
proving a sharp Kramers' law for neural fields poses substanial difficulties
but that one may transfer techniques from stochastic partial differential
equations to establish a large deviation principle (LDP). Then we demonstrate
that an efficient finite-dimensional approximation of the stochastic neural
field equation can be achieved using a Galerkin method and that the resulting
finite-dimensional rate function for the LDP can have a multi-scale structure
in certain cases. These results form the starting point for an efficient
practical computation of the LDP. Our approach also provides the technical
basis for further rigorous study of noise-induced transitions in neural fields
based on Galerkin approximations.


title: Universal Relation for the Inelastic Two-Body Loss Rate

abstract:
  Strongly-interacting systems consisting of particles that interact through a
large scattering length satisfy universal relations that relate many of their
central properties to the contact, which measures the number of pairs with
small separations. We use the operator product expansion of quantum field
theory to derive the universal relation for the inelastic 2-body loss rate. A
simple universal relation between the loss rate and the contact is obtained by
truncating the expansion after the lowest dimension operator. We verify the
universal relation explicitly by direct calculations in the low-density limit
at nonzero temperature. This universal relation can be tested experimentally
using ultracold quantum gases of atoms in hyperfine states that have an
inelastic spin-relaxation channel.


title: On Branching Rules of Depth-Zero Representations

abstract:
  Using Bruhat-Tits theory, we analyse the restriction of depth-zero
representations of a semisimple simply connected $p$-adic group $G$ to a
maximal compact subgroup $K$. We prove the coincidence of branching rules
within classes of Deligne-Lusztig supercuspidal representations. Furthermore,
we show that under obvious compatibility conditions, the restriction to $K$ of
a Deligne-Lusztig supercuspidal representation of $G$ intertwines with the
restriction of a depth-zero principal series representation in infinitely many
distinct components of arbitrarily large depth. Several qualitative and
quantitative results are obtained, and their use is illustrated in an example.


title: Spontaneously Broken Conformal Symmetry: Dealing with the Trace Anomaly

abstract:
  The majority of renormalizable field theories possessing the scale invariance
at the classical level exhibits the trace anomaly once quantum corrections are
taken into account. This leads to the breaking of scale and conformal
invariance. At the same time any realistic theory must contain gravity and is
thus non-renormalizable. We show that discarding the renormalizability it is
possible to construct viable models allowing to preserve the scale invariance
at the quantum level. We present explicit one-loop computations for two toy
models to demonstrate the main idea of the approach. Constructing the
renormalized energy momentum tensor we show that it is traceless, meaning that
the conformal invariance is also preserved.


title:
Harmonic Singular Integrals and Steerable Wavelets in
  $L_2(\mathbb{R}^d)$

abstract:
  Here we present a method of constructing steerable wavelet frames in
$L_2(\mathbb{R}^d)$ that generalizes and unifies previous approaches, including
Simoncelli's pyramid and Riesz wavelets. The motivation for steerable wavelets
is the need to more accurately account for the orientation of data. Such
wavelets can be constructed by decomposing an isotropic mother wavelet into a
finite collection of oriented mother wavelets. The key to this construction is
that the angular decomposition is an isometry, whereby the new collection of
wavelets maintains the frame bounds of the original one. The general method
that we propose here is based on partitions of unity involving spherical
harmonics. A fundamental aspect of this construction is that Fourier
multipliers composed of spherical harmonics correspond to singular integrals in
the spatial domain. Such transforms have been studied extensively in the field
of harmonic analysis, and we take advantage of this wealth of knowledge to make
the proposed construction practically feasible and computationally efficient.


title:
Realization of Deterministic Quantum Teleportation with Solid State
  Qubits

abstract:
  Transferring the state of an information carrier from a sender to a receiver
is an essential primitive in both classical and quantum communication and
information processing. In a quantum process known as teleportation the unknown
state of a quantum bit can be relayed to a distant party using shared
entanglement and classical information. Here we present experiments in a
solid-state system based on superconducting quantum circuits demonstrating the
teleportation of the state of a qubit at the macroscopic scale. In our
experiments teleportation is realized deterministically with high efficiency
and achieves a high rate of transferred qubit states. This constitutes a
significant step towards the realization of repeaters for quantum communication
at microwave frequencies and broadens the tool set for quantum information
processing with superconducting circuits.


title: The orientations of the Giza pyramids and associated structures

abstract:
  Ever since Flinders Petrie undertook a theodolite survey on the Giza plateau
in 1881 and drew attention to the extraordinary degree of precision with which
the three colossal pyramids are oriented upon the four cardinal directions,
there have been a great many suggestions as to how this was achieved and why it
was of importance. Surprisingly, given the many astronomical hypotheses and
speculations that have been offered in the intervening 130 years, there have
been remarkably few attempts to reaffirm or improve on the basic survey data
concerning the primary orientations.
  This paper presents the results of a week-long Total Station survey
undertaken by the authors during December 2006 whose principal aim was to
clarify the basic data concerning the orientation of each side of the three
large pyramids and to determine, as accurately as possible, the orientations of
as many as possible of the associated structures. The principal difference
between this and all previous surveys is that it focuses upon measurements of
sequences of points along multiple straight and relatively well preserved
structural segments, with best-fit techniques being used to provide the best
estimate of their orientation, as opposed to simple triangulation between
directly identified or extrapolated corners.
  Our results suggest that there is only a very slight difference in
orientation (c. 0.5 arc minutes) between the north-south axes of Khufu's and
Khafre's pyramids, that the sides of Khafre's are more perfectly perpendicular
than those of Khufu's, and that the east-west axis is closer to true
cardinality in both cases. The broader context of associated structures
suggests that the east-west orientation in relation to sunrise or (in one case)
sunset may have been a, or even the, key factor in many cases.


title: Klein paradox for a pn junction in multilayer graphene

abstract:
  Charge carriers in single and multilayered graphene systems behave as chiral
particles due to the particular lattice symmetry of the crystal. We show that
the interplay between the meta-material properties of graphene multilayers and
the pseudospinorial properties of the charge carriers result in the occurrence
of Klein and anti-Klein tunneling for rhombohedral stacked multilayers. We
derive an algebraic formula predicting the angles at which these phenomena
occur and support this with numerical calculations for systems up to four
layers. We present a decomposition of an arbitrarily stacked multilayer into
pseudospin doublets that have the same properties as rhombohedral systems with
a lower number of layers.


title: Semi-automatic selection of summary statistics for ABC model choice

abstract:
  A central statistical goal is to choose between alternative explanatory
models of data. In many modern applications, such as population genetics, it is
not possible to apply standard methods based on evaluating the likelihood
functions of the models, as these are numerically intractable. Approximate
Bayesian computation (ABC) is a commonly used alternative for such situations.
ABC simulates data x for many parameter values under each model, which is
compared to the observed data xobs. More weight is placed on models under which
S(x) is close to S(xobs), where S maps data to a vector of summary statistics.
Previous work has shown the choice of S is crucial to the efficiency and
accuracy of ABC. This paper provides a method to select good summary statistics
for model choice. It uses a preliminary step, simulating many x values from all
models and fitting regressions to this with the model as response. The
resulting model weight estimators are used as S in an ABC analysis. Theoretical
results are given to justify this as approximating low dimensional sufficient
statistics. A substantive application is presented: choosing between competing
coalescent models of demographic growth for Campylobacter jejuni in New Zealand
using multi-locus sequence typing data.


title: The Proper Motion of PSR J0205+6449 in 3C 58

abstract:
  We report on sensitive phase-referenced and gated 1.4-GHz VLBI radio
observations of the pulsar PSR J0205+6449 in the young pulsar-wind nebula 3C
58, made in 2007 and 2010. We employed a novel technique where the ~105-m Green
Bank telescope is used simultaneously to obtain single-dish data used to
determine the pulsar's period as well as to obtain the VLBI data, allowing the
VLBI correlation to be gated synchronously with the pulse to increase the
signal-to-noise. The high timing noise of this young pulsar precludes the
determination of the proper motion from the pulsar timing. We derive the
position of the pulsar accurate at the milliarcsecond level, which is
consistent with a re-determined position from the Chandra X-ray observations.
We reject the original tentative optical identification of the pulsar by
Shearer and Neustroev (2008), but rather identify a different optical
counterpart on their images, with R-band magnitude ~24. We also determine an
accurate proper motion for PSR J0205+6449 of (2.3 +- 0.3) mas/yr, corresponding
to a projected velocity of only (35 +- 6) km/s for a distance of 3.2 kpc, at
p.a. -38 deg. This projected velocity is quite low compared to the velocity
dispersion of known pulsars of ~200 km/s. Our measured proper motion does not
suggest any particular kinematic age for the pulsar.


title: Monoidal ring and coring structures obtained from wreaths and cowreaths

abstract:
  Let $A$ be an algebra in a monoidal category $\Cc$, and let $X$ be an object
in $\Cc$. We study $A$-(co)ring structures on the left $A$-module $A\ot X$.
These correspond to (co)algebra structures in $EM(\Cc)(A)$, the Eilenberg-Moore
category associated to $\Cc$ and $A$. The ring structures are in bijective
correspondence to wreaths in $\Cc$, and their category of representations is
the category of representations over the induced wreath product. The coring
structures are in bijective correspondence to cowreaths in $\Cc$, and their
category of corepresentations is the category of generalized entwined modules.
We present several examples coming from (co)actions of Hopf algebras and their
generalizations. Various notions of smash products that have appeared in the
literature appear as special cases of our construction.


title: CMB Anisotropies by Collapsing Textures

abstract:
  CMB photons passing through a collapsing texture knot receive an energy
shift, creating characteristic cold and hot spots on the sky. We calculate the
anisotropy pattern produced by collapsing texture knots of arbitrary shape. The
texture dynamics are solved numerically on a Minkowski background.


title:
Subtraction of temperature induced phase noise in the LISA frequency
  band

abstract:
  Temperature fluctuations are expected to be one of the limiting factors for
gravitational wave detectors in the very low frequency range. Here we report
the characterisation of this noise source in the LISA Pathfinder optical bench
and propose a method to remove its contribution from the data. Our results show
that temperature fluctuations are indeed limiting our measurement below one
millihertz, and that their subtraction leads to a factor 5.6 (15 dB) reduction
in the noise level at the lower end of the LISA measurement band 10^{-4} Hz,
which increases to 20.2 (26 dB) at even lower frequencies, i.e., 1.5x10^{-5}
Hz. The method presented here can be applied to the subtraction of other noise
sources in gravitational wave detectors in the general situation where multiple
sensors are used to characterise the noise source.


title:
Dephasing enhanced transport in nonequilibrium strongly correlated
  quantum systems

abstract:
  A key insight from recent studies is that noise, such as dephasing, can
improve the efficiency of quantum transport by suppressing coherent
single-particle interference effects. However, it is not yet clear whether
dephasing can enhance transport in an interacting many-body system. Here, we
address this question by analyzing the transport properties of a boundary
driven spinless fermion chain with nearest-neighbor interactions subject to
bulk dephasing. The many-body nonequilibrium stationary state is determined
using large-scale matrix product simulations of the corresponding quantum
master equation. We find dephasing enhanced transport only in the strongly
interacting regime, where it is shown to induce incoherent transitions bridging
the gap between bound dark states and bands of mobile eigenstates. The generic
nature of the transport enhancement is illustrated by a simple toy model, which
contains the basic elements required for its emergence. Surprisingly, the
effect is significant even in the linear response regime of the full system,
and it is predicted to exist for any large and finite chain. The response of
the system to dephasing also establishes a signature of an underlying
nonequilibrium phase transition between regimes of transport degradation and
enhancement. The existence of this transition is shown not to depend on the
integrability of the model considered. As a result, dephasing enhanced
transport is expected to persist in more realistic nonequilibrium strongly
correlated systems.


title:
Ultra-luminous X-ray Sources as Supercritical Accretion Disks: Spectral
  Energy Distributions

abstract:
  We describe a model of spectral energy distribution in supercritical
accretion disks (SCAD) based on the conception by Shakura and Sunyaev. We apply
this model to five ultra-luminous X-ray sources (ULXs). In this approach, the
disk becomes thick at distances to the center less than the spherization
radius, and the temperature dependence is T \propto r^{-1/2}. In this region
the disk luminosity is L_bol ~ L_Edd ln(Mdot/Mdot_Edd), and strong wind arises
forming a wind funnel above the disk. Outside the spherization radius, the disk
is thin and its total luminosity is Eddington, L_Edd. The thin disk heats the
wind from below. From the inner side of the funnel the wind is heated by the
supercritical disk. In this paper we do not consider Comptonization in the
inner hot winds which must cover the deep supercritical disk regions. Our model
is technically similar to the DISKIR model of Gierlinski et al. The models
differ in disk type (standard - supercritical) and irradiation (disk - wind).
We propose to distinguish between these two models in the X-ray region, ~0.3 -
1 keV, where the SCAD model has a flat nu F_nu spectrum, and the DISKIR model
never has a flat part, as it is based on the standard alpha-disk. An important
difference between the models can be found in their resulting black hole
masses. In application to the ULX spectra, the DISKIR model yields black hole
masses of a few hundred solar masses, whereas the SCAD model produces
stellar-mass black holes ~10 M_sun.


title: General CMB bispectrum analysis using wavelets and separable modes

abstract:
  In this paper we combine partial-wave (`modal') methods with a wavelet
analysis of the CMB bispectrum. Our implementation exploits the advantages of
both approaches to produce robust, reliable and efficient estimators which can
constrain the amplitude of arbitrary primordial bispectra. This will be
particularly important for upcoming surveys such as \emph{Planck}. A key
advantage is the computational efficiency of calculating the inverse covariance
matrix in wavelet space, producing an error bar which is close to optimal. We
verify the efficacy and robustness of the method by applying it to WMAP7 data,
finding $\fnllocal=38.4\pm 23.6$ and $\fnlequil=-119.2\pm123.6$.


title: Dipolar confinement-induced resonances of ultracold gases in waveguides

abstract:
  We develop a non-perturbative theoretical framework to treat collisions with
generic anisotropic interactions in quasi-one-dimensional geometries. Our
method avoids the limitations of pseudopotential theory allowing to include
accurately long-range anisotropic interactions. Analyzing ultracold dipolar
collisions in a harmonic waveguide we predict dipolar confinement-induced
resonances (DCIRs) which are attributed to different angular momentum states.
The analytically derived resonance condition reveals in detail the interplay of
the confinement with the anisotropic nature of the dipole-dipole interactions.
The results are in excellent agreement with ab initio numerical calculations
confirming the robustness of the presented approach. The exact knowledge of the
positions of DCIRs may pave the way for the experimental realization e.g.
Tonks-Girardeau-like or super-Tonks-Girardeau-like phases in effective
one-dimensional dipolar gases.


title:
Mixing of blackbodies: Increasing our view of inflation to 17 e-folds
  with spectral distortions from Silk damping

abstract:
  Silk damping in the early Universe, before and during recombination, erases
anisotropies in the cosmic microwave background (CMB) on small scales. This
power, which disappears from anisotropies, appears in the monopole as y-type,
i-type and \mu-type distortions. The observation of the CMB spectral
distortions will thus make available to us the information about the primordial
power spectrum on scales corresponding to the comoving wavenumbers $8< k < 10^4
Mpc^{-1}$ increasing our total view of inflation, when combined with CMB
anisotropies, to span 17 e-folds. These distortions can be understood simply as
mixing of blackbodies of different temperatures and the subsequent
comptonization of the resulting distortions.


title: Top couplings and top partners

abstract:
  We review the model-independent description of the couplings of the top quark
to the Higgs and gauge bosons in theories beyond the Standard Model. Then we
examine these couplings in the case of arbitrary heavy vector-like quarks
mixing with the third family. We also discuss the couplings of these top
partners, and comment on implications for LHC searches.


title: Greedy is as Good as Delaunay (Almost)

abstract:
  Let S be a planar point set. Krznaric and Levcopoulos proved that given the
Delaunay triangulation DT(S) for S, one can find the greedy triangulation GT(S)
in linear time. We provide a (partial) converse of this result: given GT(S), it
is possible to compute DT(S) in linear expected time. Thus, these structures
are basically equivalent.
  To obtain our result, we generalize another algorithm by Krznaric and
Levcopoulos to find a hierarchical clustering for S in linear time, once DT(S)
is known. We show that their algorithm remains (almost) correct for any
triangulation of bounded dilation, i.e., any triangulation in which the
shortest path distance between any two points approximates their Euclidean
distance. In general, however, the resulting running time may be superlinear.
Nonetheless, we can show that the properties of the greedy triangulation
suffice to guarantee a linear time bound.


title: Interaction between domain walls in chiral p-wave superconductors

abstract:
  We calculate microscopically the interaction energy of domain walls
separating degenerate ground states in a chiral p-wave superconductor. The
interaction is mediated by the quasiparticles experiencing Andreev scattering
at the domain walls. As a by-product, we derive a useful general expression for
the free energy of an arbitrary nonuniform texture of the order parameter in
terms of the quasiparticle scattering matrix.


title: Optimal spatiotemporal focusing through complex scattering media

abstract:
  We present a new approach for spatiotemporal focusing through complex
scattering media by wave front shaping. Using a nonlinear feedback signal to
shape the incident pulsed wave front, we show that the limit of a
spatiotemporal matched filter can be achieved, i.e., the wave amplitude at the
intended time and focus position is maximized for a given input energy. It is
exactly what is also achieved with time-reversal. Demonstrated with ultrasound
experiments, our method is generally applicable to all types of waves.


title:
Conditional spin counting statistics as a probe of Coulomb interaction
  and spin-resolved bunching

abstract:
  Full counting statistics is a powerful tool to characterize the noise and
correlations in transport through mesoscopic systems. In this work, we propose
the theory of conditional spin counting statistics, i.e., the statistical
fluctuations of spin-up (down) current given the observation of the spin-down
(up) current. In the context of transport through a single quantum dot, it is
demonstrated that a strong Coulomb interaction leads to a conditional spin
counting statistics that exhibits a substantial change in comparison to that
without Coulomb repulsion. It thus can be served as an effective way to probe
the Coulomb interactions in mesoscopic transport systems. In case of spin
polarized transport, it is further shown that the conditional spin counting
statistics offers a transparent tool to reveal the spin-resolved bunching
behavior.


title:
Effect of material stiffness on intermodulation response in dynamic
  atomic force microscopy

abstract:
  We perform simulations and experiments on an oscillating atomic force
microscope cantilever approaching a surface, where the intermodulation response
of the cantilever driven with two pure harmonic tones is investigated. In the
simulations, the tip and surface interact with a conservative nonlinear force,
and the parameter space of approach distance and surface stiffness is explored.
Approach experiments are carried out on three surfaces with widely varying
stiffness. Qualitative similarities between simulations and experiment can be
seen, but quantitative comparison is difficult due to the overly idealized
tip-surface force model used in the simulation.


title:
Non-local transport properties of nanoscale conductor-microwave cavity
  systems

abstract:
  Recent experimental progress in coupling nanoscale conductors to
superconducting microwave cavities has opened up for transport investigations
of the deep quantum limit of light-matter interactions, with tunneling
electrons strongly coupled to individual cavity photons. We have investigated
theoretically the most basic cavity-conductor system with strong, single photon
induced non-local transport effects; two spatially separated double quantum
dots (DQD:s) resonantly coupled to the fundamental cavity mode. The system,
described by a generalized Tavis-Cummings model, is investigated within a
quantum master equation formalism, allowing us to account for both the
electronic transport properties through the DQD:s as well as the coherent,
non-equilibrium cavity photon state. We find sizeable non-locally induced
current and current cross-correlations mediated by individual photons. From a
full statistical description of the electron transport we further reveal a
dynamical channel blockade in one DQD lifted by photon emission due to
tunneling through the other DQD. Moreover, large entanglement between the
orbital states of electrons in the two DQD:s is found for small DQD-lead
temperatures.


title: Holographic Type II Goldstone bosons

abstract:
  The Goldstone theorem implies the appearance of an ungapped mode whenever a
continuous global symmetry is spontaneously broken. In general it does not say
anything about the precise form of the dispersion relation nor does it imply
that there is one massless mode for each broken symmetry generator. It is a
well-established fact that even for relativistic field theories in the presence
of a chemical potential Goldstone modes with quadratic dispersion relation, the
type II Goldstone bosons, appear in the spectrum. We develop two holographic
models that feature type II Goldstone modes as part of the quasinormal mode
spectrum. The models are based on simple generalizations with U(2) symmetry of
the well-studied holographic s-wave superfluid. Our results include Goldstone
modes without broken generators but with unusual realization of symmetries and
a frequency dependent conductivity of striking resemblance to the one of
Graphene.


title: Dyson-Schwinger approach to strongly coupled theories

abstract:
  Although nonperturbative functional methods are often associated with low
energy Quantum Chromodynamics, contemporary studies indicate that they provide
reliable tools to characterize a much wider spectrum of strongly interacting
many-body systems. In this review, we aim to provide a modest overview on a few
notable applications of Dyson-Schwinger equations to QCD and condensed matter
physics. After a short introduction, we lay out some formal considerations and
proceed by addressing the confinement problem. We discuss in some detail the
heavy quark limit of Coulomb gauge QCD, in particular the simple connection
between the nonperturbative Green's functions of Yang-Mills theory and the
confinement potential. Landau gauge results on the infrared Yang-Mills
propagators are also briefly reviewed. We then focus on less common
applications, in graphene and high-temperature superconductivity. We discuss
recent developments, and present theoretical predictions that are supported by
experimental findings.


title: Thin domains with doubly oscillatory boundary

abstract:
  We consider a 2-dimensional thin domain with order of thickness {\epsilon}
which presents oscillations of amplitude also {\epsilon} on both boundaries,
top and bottom, but the period of the oscillations are of different order at
the top and at the bottom. We study the behavior of the Laplace operator with
Neumann boundary condition and obtain its asymptotic homogenized limit as the
parameter {\epsilon} goes to 0. We are interested in understanding how this
different oscillatory behavior at the boundary, influences the limit problem.


title: Smoothed quantile regression processes for binary response models

abstract:
  In this paper, we consider binary response models with linear quantile
restrictions. Considerably generalizing previous research on this topic, our
analysis focuses on an infinite collection of quantile estimators. We derive a
uniform linearisation for the properly standardized empirical quantile process
and discover some surprising differences with the setting of continuously
observed responses. Moreover, we show that considering quantile processes
provides an effective way of estimating binary choice probabilities without
restrictive assumptions on the form of the link function, heteroskedasticity or
the need for high dimensional non-parametric smoothing necessary for approaches
available so far. A uniform linear representation and results on asymptotic
normality are provided, and the connection to rearrangements is discussed.


title: Role of temporal inference in the recognition of textual inference

abstract:
  This project is a part of nature language processing and its aims to develop
a system of recognition inference text-appointed TIMINF. This type of system
can detect, given two portions of text, if a text is semantically deducted from
the other. We focused on making the inference time in this type of system. For
that we have built and analyzed a body built from questions collected through
the web. This study has enabled us to classify different types of times
inferences and for designing the architecture of TIMINF which seeks to
integrate a module inference time in a detection system inference text. We also
assess the performance of sorties TIMINF system on a test corpus with the same
strategy adopted in the challenge RTE.


title:
Comments on "Resource placement in Cartesian product of networks"
  [Imani, Sarbazi-Azad and Zomaya, J. Parallel Distrib. Comput., 70 (2010)
  481-495]

abstract:
  The present note points out a number of errors, omissions, redundancies and
arbitrary deviations from the standard terminology in the paper "Resource
placement in Cartesian product of networks," by N. Imani, H. Sarbazi-Azad and
A.Y. Zomaya [J. Parallel Distrib. Comput. 70 (2010) 481-495].


title: Any Light Particle Search II -- Technical Design Report

abstract:
  This document constitutes an excerpt of the Technical Design Report for the
second stage of the "Any Light Particle Search" (ALPS-II) at DESY as submitted
to the DESY PRC in August 2012 and reviewed in November 2012. ALPS-II is a
"Light Shining through a Wall" experiment which searches for photon
oscillations into weakly interacting sub-eV particles. These are often
predicted by extensions of the Standard Model and motivated by astrophysical
phenomena. The first phases of the ALPS-II project were approved by the DESY
management on February 21st, 2013.

categories: physics.ins-det astro-ph.CO hep-ex hep-ph


title: Solvable, reductive and quasireductive supergroups

abstract:
  This work was inspired by two natural questions. The first question is when
Lie(G')=Lie(G)', where G is a connected algebraic supergroup defined over a
field of characteristic zero. The second question is whether the unipotent
radical of any normal supersubgroup H of G coincides with the intersection of H
and G_u, where G_u is the unipotent radical of G. Both questions have
affirmative answers in the category of algebraic groups (in the second case one
has to assume additionally that G and H are reduced whenever char K >0).
Surprisingly, using the technique of Harish-Chandra superpairs and a complete
description of an action of an algebraic supergroup on an abelian supergroups
by supergroup automorphisms we found out rather simple counterexamples to both
questions. Besides, the second counterexample shows that the reductivity of G
does not imply that G_{ev} has even finite unipotent radical. On the other
hand, if G_{ev} is reductive, then it is easy to see that G_u is finite (odd)
supergroup. In other words, the reductivity of an algebraic supergroup does not
correspond to the reductivity of its largest even subgroup in contrast to such
properties as unipotency or solvability. In the last section of our article we
describe reductive algebraic supergroups in terms of sandwich pairs and give
necessary and sufficient conditions for an algebraic supergroup to be
quasireductive. The last result complements the recent Serganova's description
of quasireductive supergroups in terms of structural properties of their Lie
superalgebras. Our approach is focused on the normal subgroup structure.


title: NGC 7419 as a template for red supergiant clusters

abstract:
  The open cluster NGC 7419 is known to contain five red supergiants and a very
high number of Be stars. However, there are conflicting reports about its age
and distance that prevent a useful comparison with other clusters. We intend to
obtain more accurate parameters for NGC 7419, using techniques different from
those of previous authors, so that it may be used as a calibrator for more
obscured clusters. We obtained Str\"omgren photometry of the open cluster NGC
7419, as well as classification spectroscopy of ~20 stars in the area. We then
applied standard analysis and classification techniques. We find a distance of
4+-0.4 kpc and an age of 14+-2 Myr for NGC 7419. The main-sequence turn-off is
found at spectral type B1, in excellent agreement. We identify 179 B-type
members, implying that there are more than 1200 $M_{\sun}$ in B stars at
present. Extrapolating this to lower masses indicates an initial cluster mass
of between 7000 and 10000 Msolar, depending on the shape of the Initial Mass
Function. We find a very high fraction (~40%) of Be stars around the turn-off,
but very few Be stars at lower masses. We also report for the first time a
strong variability in the emission characteristics of Be stars. We verified
that the parameters of the red supergiant members can be used to obtain
accurate cluster parameters. NGC 7419 is sufficiently massive to serve as a
testbed for theoretical predictions and as a template to compare more obscured
clusters. The distribution of stars above the main-sequence turn-off is
difficult to accommodate with current evolutionary tracks. Though the presence
of five red supergiants is marginally consistent with theoretical expectations,
the high number of Be stars and very low number of luminous evolved B stars
hint at some unknown physical factor that is not considered in current
synthesis models.


title: On a Boltzmann type price formation model

abstract:
  In this paper we present a Boltzmann type price formation model, which is
motivated by a parabolic free boundary model for the evolution of the prize
presented by Lasry and Lions in 2007. We discuss the mathematical analysis of
the Boltzmann type model and show that its solutions converge to solutions of
the model by Lasry and Lions as the transaction rate tends to infinity.
Furthermore we analyse the behaviour of the initial layer on the fast time
scale and illustrate the price dynamics with various numerical experiments.


title: Universal nowhere dense subsets of locally compact manifolds

abstract:
  In each manifold $M$ modeled on a finite or infinite dimensional cube
$[0,1]^n$ we construct a closed nowhere dense subset $S\subset M$ (called a
spongy set) which is a universal nowhere dense set in $M$ in the sense that for
each nowhere dense subset $A\subset M$ there is a homeomorphism $h:M\to M$ such
that $h(A)\subset S$. The key tool in the construction of spongy sets is a
theorem on topological equivalence of certain decompositions of manifolds. A
special case of this theorem says that two vanishing cellular strongly
shrinkable decompositions $\mathcal A,\mathcal B$ of a Hilbert cube manifold
$M$ are topologically equivalent if any two non-singleton elements
$A\in\mathcal A$ and $B\in\mathcal B$ of these decompositions are ambiently
homeomorphic.


title: Presheaf models of quantum computation: an outline

abstract:
  This paper outlines the construction of categorical models of higher-order
quantum computation. We construct a concrete denotational semantics of Selinger
and Valiron's quantum lambda calculus, which was previously an open problem. We
do this by considering presheaves over appropriate base categories arising from
first-order quantum computation. The main technical ingredients are Day's
convolution theory and Kelly and Freyd's notion of continuity of functors. We
first give an abstract description of the properties required of the base
categories for the model construction to work. We then exhibit a specific
example of base categories satisfying these properties.


title: Universal meager $F_\sigma$-sets in locally compact manifolds

abstract:
  In each manifold $M$ modeled on a finite or infinite dimensional cube
$[0,1]^n$ we construct a meager $F_\sigma$-subset $X\subset M$ which is
universal meager in the sense that for each meager subset $A\subset M$ there is
a homeomorphism $h:M\to M$ such that $h(A)\subset X$. We also prove that any
two universal meager $F_\sigma$-sets in $M$ are ambiently homeomorphic.


title: On Matroids and Linearly Independent Set Families

abstract:
  New families of matroids are constructed in this note. These new fami- lies
are derived from the concept of linearly independent set family (LISF)
introduced by Eicker and Ewald [Linear Algebra and its Applications 388 (2004)
173-191]. The proposed construction generalizes in a natural way the well known
class of vectorial matroids over a field.


title:
Stochastic bias of colour-selected BAO tracers by joint clustering-weak
  lensing analysis

abstract:
  The baryon acoustic oscillation (BAO) feature in the two-point correlation
function of galaxies supplies a standard ruler to probe the expansion history
of the Universe. We study here several galaxy selection schemes, aiming at
building an emission-line galaxy (ELG) sample in the redshift range
$0.6<z<1.7$, that would be suitable for future BAO studies, providing a highly
biased galaxy sample. We analyse the angular galaxy clustering of galaxy
selections at the redshifts 0.5, 0.7, 0.8, 1 and 1.2 and we combine this
analysis with a halo occupation distribution (HOD) model to derive the
properties of the haloes these galaxies inhabit, in particular the galaxy bias
on large scales. We also perform a weak lensing analysis (aperture statistics)
to extract the galaxy bias and the cross-correlation coefficient and compare to
the HOD prediction.
  We apply this analysis on a data set composed of the photometry of the deep
co-addition on Sloan Digital Sky Survey (SDSS) Stripe 82 (225 deg$^2$), of
Canda-France-Hawai Telescope/Stripe 82 deep \emph{i}-band weak lensing survey
and of the {\it Wide-Field Infrared Survey Explorer}infrared photometric band
W1.
  The analysis on the SDSS-III/constant mass galaxies selection at $z=0.5$ is
in agreement with previous studies on the tracer, moreover we measure its
cross-correlation coefficient $r=1.16\pm0.35$. For the higher redshift bins, we
confirm the trends that the brightest galaxy populations selected are strongly
biased ($b>1.5$), but we are limited by current data sets depth to derive
precise values of the galaxy bias. A survey using such tracers of the mass
field will guarantee a high significance detection of the BAO.


title: Universal nowhere dense and meager sets in Menger manifolds

abstract:
  In each Menger manifold $M$ we construct: (i) a closed nowhere dense subset
$M_0$ which is homeomorphic to $M$ and is universal nowhere dense in the sense
that for each nowhere dense set $A\subset M$ there is a homeomorphism $h$ of
$M$ such that $h(A)\subset M_0$; (ii) a meager $F_\sigma$-set $\Sigma_0\subset
M$ which is universal meager in the sense that for each meager subset $B\subset
M$ there is a homeomorphism $h$ of $M$ such that $h(B)\subset \Sigma_0$.
  Also we prove that any two universal meager $F_\sigma$-sets in $M$ are
ambiently homeomorphic.


title: A realistic distributed storage system: the rack model

abstract:
  In a realistic distributed storage environment, storage nodes are usually
placed in racks, a metallic support designed to accommodate electronic
equipment. It is known that the communication (bandwidth) cost between nodes
which are in the same rack is much lower than between nodes which are in
different racks.
  In this paper, a new model, where the storage nodes are placed in two racks,
is proposed and analyzed. Moreover, the two-rack model is generalized to any
number of racks. In this model, the storage nodes have different repair costs
depending on the rack where they are placed. A threshold function, which
minimizes the amount of stored data per node and the bandwidth needed to
regenerate a failed node, is shown. This threshold function generalizes the
ones given for previous distributed storage models. The tradeoff curve obtained
from this threshold function is compared with the ones obtained from the
previous models, and it is shown that this new model outperforms the previous
ones in terms of repair cost.


title: Topologically invariant $\sigma$-ideals on the Hilbert cube

abstract:
  We study and classify topologically invariant $\sigma$-ideals with a Borel
base on the Hilbert cube and evaluate their cardinal characteristics. One of
the results of this paper solves (positively) a known problem whether the
minimal cardinalities of the families of Cantor sets covering the unit interval
and the Hilbert cube are the same.


title: Global gauges and global extensions in optimal spaces

abstract:
  We consider the problem of extending functions \phi:\to S^n to functions
u:B^{n+1}\to S^n for n=2,3. We assume \phi to belong to the critical space
W^{1,n} and we construct a W^{1,(n+1,\infty)}-controlled extension u. The
Lorentz-Sobolev space W^{1,(n+1,\infty)} is optimal for such controlled
extension. Then we use such results to construct global controlled gauges for
L^4-connections over trivial SU(2)-bundles in 4 dimensions. This result is a
global version of the local Sobolev control of connections obtained by K.
Uhlenbeck.


title:
Variability Improvement by Interface Passivation and EOT Scaling of
  InGaAs Nanowire MOSFETs

abstract:
  High performance InGaAs gate-all-around (GAA) nanowire MOSFETs with channel
length (Lch) down to 20nm have been fabricated by integrating a higher-k
LaAlO3-based gate stack with an equivalent oxide thickness of 1.2nm. It is
found that inserting an ultrathin (0.5nm) Al2O3 interfacial layer between
higher-k and InGaAs can significantly improve the interface quality and reduce
device variation. As a result, a record low subthreshold swing of 63mV/dec has
been demonstrated at sub-80nm Lch for the first time, making InGaAs GAA
nanowire devices a strong candidate for future low-power transistors.


title:
Renormalization of dimension-six operators relevant for the Higgs decays
  $h\rightarrow \gamma\gamma,\gamma Z$

abstract:
  The discovery of the Higgs boson has opened a new window to test the SM
through the measurements of its couplings. Of particular interest is the
measured Higgs coupling to photons which arises in the SM at the one-loop
level, and can then be significantly affected by new physics. We calculate the
one-loop renormalization of the dimension-six operators relevant for
$h\rightarrow \gamma\gamma, \gamma Z$, which can be potentially important since
it could, in principle, give log-enhanced contributions from operator mixing.
We find however that there is no mixing from any current-current operator that
could lead to this log-enhanced effect. We show how the right choice of
operator basis can make this calculation simple. We then conclude that
$h\rightarrow \gamma\gamma, \gamma Z$ can only be affected by RG mixing from
operators whose Wilson coefficients are expected to be of one-loop size, among
them fermion dipole-moment operators which we have also included.


title: Low Latency Communications

abstract:
  Numerous applications demand communication schemes that minimize the
transmission delay while achieving a given level of reliability. An extreme
case is high-frequency trading whereby saving a fraction of millisecond over a
route between Chicago and New York can be a game-changer. While such
communications are often carried by fiber, microwave links can reduce
transmission delays over large distances due to more direct routes and faster
wave propagation. In order to bridge large distances, information is sent over
a multihop relay network.
  Motivated by these applications, this papers present an information-theoretic
approach to the design of optimal multihop microwave networks that minimizes
end-to-end transmission delay. To characterize the delay introduced by coding,
we derive error exponents achievable in multihop networks. We formulate and
solve an optimization problem that determines optimal selection of
amplify-and-forward and decode-and-forward relays. We present the optimal
solution for several examples of networks. We prove that in high SNR the
optimum transmission scheme is for all relays to perform amplify-and-forward.
We then analyze the impact of deploying noisy feedback


title:
Magnetic Fields in the Milky Way and in Galaxies (revised version of
  March 2021)

abstract:
  Most of the visible matter in the Universe is ionized, so that cosmic
magnetic fields are quite easy to generate and due to the lack of magnetic
monopoles hard to destroy. Magnetic fields have been measured in or around
practically all celestial objects, either by in-situ measurements of
spacecrafts or by the electromagnetic radiation of embedded cosmic rays, gas,
or dust. The Earth, the Sun, solar planets, stars, pulsars, the Milky Way,
nearby galaxies, more distant (radio) galaxies, quasars, and even intergalactic
space in clusters of galaxies have significant magnetic fields, and even larger
volumes of the Universe may be permeated by 'dark' magnetic fields. Information
on cosmic magnetic fields has increased enormously as the result of the rapid
development of observational methods, especially in radio astronomy. In the
Milky Way, a wealth of magnetic phenomena was discovered that are only partly
related to objects visible in other spectral ranges. The large-scale structure
of the Milky Way's magnetic field is still under debate. The available data for
external galaxies can well be explained by field amplification and ordering via
the dynamo mechanism. The measured field strengths and the similarity of field
patterns and flow patterns of the diffuse ionized gas give strong indication
that galactic magnetic fields are dynamically important. They may affect the
formation of spiral arms, outflows, and the general evolution of galaxies. In
spite of our increasing knowledge on magnetic fields, many important questions
on the origin and evolution of magnetic fields, like their first occurrence in
young galaxies, or the existence of large-scale intergalactic fields remained
unanswered. 'Cosmic magnetism' is a key science project for several existing
and planned radio telescopes, like LOFAR and the SKA.


title:
Low-temperature specific heat of graphite and CeSb2: Validation of a
  quasi-adiabatic continuous method

abstract:
  We present the application of a fast quasi-adiabatic continuous method to the
measurement of specific heat at 4He temperatures, which can be used for the
study of a wide range of materials. The technique can be performed in the same
configuration used for the relaxation method, as the typical time constants
between calorimetric cell and thermal sink at 4.2 K are chosen to be of the
order of tau~30 s. The accuracy in the absolute values have been tested by
comparing them to relaxation-method results obtained in the same samples
(performed in situ using the same set-up), with a deviation between the
absolute values < 3% in the whole temperature range. This new version of the
continuous calorimetric method at low temperatures allows us to completely
characterize and measure a sample within a few hours with a high density of
data points, whereas when employing other methods we typically need a few days.
An exhaustive study has been performed for reproducibility to be tested. In the
present work, we have applied this method to two different substances: CeSb2,
which exhibits three magnetic transitions at 15.5 K, 11.7 K and 9.5 K, and
graphite, both highly-oriented pyrolytic graphite (HOPG) and natural crystals.
Our results on these graphites are discussed in comparison with previous
published data on different kinds of graphite samples.


title:
Inverse spectral problems for Schr\"odinger and pseudo-differential
  operators

abstract:
  Starting from the semi-classical spectrum of Schr\"odinger operators
$-h^2\Delta+V$ (on $\mathbb{R}^n$ or on a Riemannian manifold) it is possible
to detect critical levels of the potential $V$. Via micro-local methods one can
express spectral statistics in terms of different invariants: \begin{itemize}
\item Geometry of energy surfaces (heat invariant like). \item Classical orbits
(wave invariants). \item But also classical equilibria (new wave invariants).
\end{itemize} Any critical point of $V$ with zero momentum is an equilibrium of
the flow and generates many singularities in the semi-classical distribution of
eigenvalues. Via sharp spectral estimates, this phenomena indicates the
presence of a critical energy level and the information contained in this
singularity allows to reconstruct partially the local shape of $V$. Several
generalizations of this approach are also proposed. Keywords : Spectral
analysis, P.D.E., Micro-local analysis; Schr\"odinger operators; Inverse
spectral problems.


title: 3T MR-Guided Brachytherapy for Gynecologic Malignancies

abstract:
  Gynecologic malignancies are a leading cause of death in women worldwide.
Standard treatment for many primary and recurrent gynecologic cancer cases
includes a combination of external beam radiation, followed by brachytherapy.
Magnetic Resonance Imaging (MRI) is benefitial in diagnostic evaluation, in
mapping the tumor location to tailor radiation dose, and in monitoring the
tumor response to treatment. Initial studies of MR-guidance in gynecologic
brachtherapy demonstrate the ability to optimize tumor coverage and reduce
radiation dose to normal tissues, resulting in improved outcomes for patients.
In this article we describe a methodology to aid applicator placement and
treatment planning for 3 Tesla (3T) MR-guided brachytherapy that was developed
specifically for gynecologic cancers. This has been used in 18 cases to date in
the Advanced Multimodality Image Guided Operating suite at Brigham and Women's
Hospital. It is comprised of state of the art methods for MR imaging, image
analysis, and treatment planning. An MR sequence using 3D-balanced steady state
free precession in a 3T MR scan was identified as the best sequence for
catheter identification with ballooning artifact at the tip. 3D treatment
planning was performed using MR images. Item in development include a software
module designed to support virtual needle trajectory planning that includes
probabilistic bias correction, graph based segmentation, and image registration
algorithms. The results demonstrate that 3T MR has a role in gynecologic
brachytherapy. These novel developments improve targeted treatment to the tumor
while sparing the normal tissues.