title: Computing in the Limit

abstract:
  We define a class of functions termed "Computable in the Limit", based on the
Machine Learning paradigm of "Identification in the Limit". A function is
Computable in the Limit if it defines a property P_p of a recursively
enumerable class A of recursively enumerable data sequences S in A, such that
each data sequence S is generated by a total recursive function s that
enumerates . Let the index s represent the data sequence S. The property
P_p(s)=x is computed by a partial recursive function f_p(s,t) such that there
exists a u where f_p(s,u)=x and for all t>=u, f_p(s,t)=x if it converges. Since
the index s is known, this is not an identification problem - instead it is
computing a common property of the sequences in A. We give a Normal Form
Theorem for properties that are Computable in the Limit, similar to Kleene's
Normal Form Theorem. We also give some examples of sets that are Computable in
the Limit, and derive some properties of Canonical and Complexity Bound
Enumerations of classes of total functions, and show that no full enumeration
of all indices of Turing machines TM_i that compute a given total function can
be Computable in the Limit.


title:
The Evolution of the Stellar Mass Functions of Star-Forming and
  Quiescent Galaxies to z = 4 from the COSMOS/UltraVISTA Survey

abstract:
  We present measurements of the stellar mass functions (SMFs) of star-forming
and quiescent galaxies to z = 4 using a sample of 95 675 galaxies in the
COSMOS/UltraVISTA field. Sources have been selected from the DR1 UltraVISTA
K_{s}-band imaging which covers a unique combination of a wide area (1.62
deg^2), to a significant depth (K_{s,tot} = 23.4). The SMFs of the combined
population are in good agreement with previous measurements and show that the
stellar mass density of the universe was only 50%, 10% and 1% of its current
value at z ~ 0.75, 2.0, and 3.5, respectively. The quiescent population drives
most of the overall growth, with the stellar mass density of these galaxies
increasing by 2.71^{+0.93}_{-0.22} dex since z = 3.5. At z > 2.5, star-forming
galaxies dominate the total SMF at all stellar masses, although a nonzero
population of quiescent galaxies persists to z = 4. Comparisons of the
K_{s}-selected star-forming galaxy SMFs to UV-selected SMFs at 2.5 < z < 4 show
reasonable agreement and suggests UV-selected samples are representative of the
majority of the stellar mass density at z > 3.5. We estimate the average mass
growth of individual galaxies by selecting galaxies at fixed cumulative number
density. The average galaxy with Log(M_{*}/M_{sun}) = 11.5 at z = 0.3 has grown
in mass by only 0.2 dex (0.3 dex) since z = 2.0(3.5), whereas those with
Log(M_{*}/M_{sun}) = 10.5 have grown by > 1.0 dex since z = 2. At z < 2, the
time derivatives of the mass growth are always larger for lower-mass galaxies,
which demonstrates that the mass growth in galaxies since that redshift is
mass-dependent and primarily bottom-up. Lastly, we examine potential sources of
systematic uncertainties on the SMFs and find that those from photo-z
templates, SPS modeling, and the definition of quiescent galaxies dominate the
total error budget in the SMFs.


title:
A Public Ks-selected Catalog in the COSMOS/UltraVISTA Field: Photometry,
  Photometric Redshifts and Stellar Population Parameters

abstract:
  We present a catalog covering 1.62 deg^2 of the COSMOS/UltraVISTA field with
PSF-matched photometry in 30 photometric bands. The catalog covers the
wavelength range 0.15um - 24um including the available GALEX, Subaru, CFHT,
VISTA and Spitzer data. Catalog sources have been selected from the DR1
UltraVISTA Ks band imaging that reaches a depth of K_{s,tot} = 23.4 AB (90%
completeness). The PSF-matched catalog is generated using position-dependent
PSFs ensuring accurate colors across the entire field. Also included is a
catalog of photometric redshifts (z_phot) for all galaxies computed with the
EAZY code. Comparison with spectroscopy from the zCOSMOS 10k bright sample
shows that up to z ~ 1.5 the z_phot are accurate to dz/(1 + z) = 0.013, with a
catastrophic outlier fraction of only 1.6%. The z_phot also show good agreement
with the z_phot from the NEWFIRM Medium Band Survey (NMBS) out to z ~ 3. A
catalog of stellar masses and stellar population parameters for galaxies
determined using the FAST spectral energy distribution fitting code is provided
for all galaxies. Also included are rest-frame U-V and V-J colors, L_2800 and
L_IR. The UVJ color-color diagram confirms that the galaxy bi-modality is
well-established out to z ~ 2. Star-forming galaxies also obey a star forming
"main sequence" out to z ~ 2.5, and this sequence evolves in a manner
consistent with previous measurements. The COSMOS/UltraVISTA Ks-selected
catalog covers a unique parameter space in both depth, area, and
multi-wavelength coverage and promises to be a useful tool for studying the
growth of the galaxy population out to z ~ 3 - 4.


title: Modeling temporal networks using random itineraries

abstract:
  We propose a procedure to generate dynamical networks with bursty, possibly
repetitive and correlated temporal behaviors. Regarding any weighted directed
graph as being composed of the accumulation of paths between its nodes, our
construction uses random walks of variable length to produce time-extended
structures with adjustable features. The procedure is first described in a
general framework. It is then illustrated in a case study inspired by a
transportation system for which the resulting synthetic network is shown to
accurately mimic the empirical phenomenology.


title:
Generalized conic functions of hv-convex planar sets: continuity
  properties and relations to X-rays

abstract:
  In the paper we investigate the continuity properties of the mapping $\Phi$
which sends any non-empty compact connected hv-convex planar set $K$ to the
associated generalized conic function $f_K$. The function $f_K$ measures the
average taxicab distance of the points in the plane from the focal set $K$ by
integration. The main area of the applications is the geometric tomography
because $f_K$ involves the coordinate X-rays' information as second order
partial derivatives \cite{NV3}. We prove that the Hausdorff-convergence implies
the convergence of the conic functions with respect to both the supremum-norm
and the $L_1$-norm provided that we restrict the domain to the collection of
non-empty compact connected hv-convex planar sets contained in a fixed box
(reference set) with parallel sides to the coordinate axes. We also have that
$\Phi^{-1}$ is upper semi-continuous as a set-valued mapping. The upper
semi-continuity establishes an approximating process in the sense that if $f_L$
is close to $f_K$ then $L$ must be close to an element $K'$ such that
$f_{K}=f_{K'}$. Therefore $K$ and $K'$ have the same coordinate X-rays almost
everywhere. Lower semi-continuity is usually related to the existence of
continuous selections. If a set-valued mapping is both upper and lower
semi-continuous at a point of its domain it is called continuous. The last
section of the paper is devoted to the case of non-empty compact convex planar
sets. We show that the class of convex bodies that are determined by their
coordinate X-rays coincides with the family of convex bodies $K$ for which
$f_K$ is a point of lower semi-continuity for $\Phi^{-1}$.


title:
Intrinsic to extrinsic phonon lifetime transition in a GaAs-AlAs
  superlattice

abstract:
  We have measured the lifetimes of two zone-center longitudinal acoustic
phonon modes, at 320 GHz and 640 GHz respectively, in a 14 nm GaAs / 2 nm AlAs
superlattice structure. By comparing measurements at 296 K and 79 K we separate
the intrinsic contribution to phonon lifetime determined by phonon-phonon
scattering from the extrinsic contribution due to defects and interface
roughness. At 296 K, the 320-GHz phonon lifetime has approximately equal
contributions from intrinsic and extrinsic scattering, whilst at 640 GHz it is
dominated by extrinsic effects. These measurements are compared with
first-principles lattice dynamics calculations of intrinsic and extrinsic
scattering rates in the superlattice. The calculated room-temperature intrinsic
lifetime of longitudinal phonons at 320 GHz is in agreement with the
experimentally measured value of 0.9 ns. The model correctly predicts the
transition from predominantly intrinsic to predominantly extrinsic scattering;
however the predicted transition occurs at higher frequencies. Our analysis
indicates that the 'interfacial atomic disorder' model is not entirely adequate
and that the observed frequency dependence of the extrinsic scattering rate is
likely to be determined by a finite correlation length of interface roughness.


title: Light Stops, Light Staus and the 125 GeV Higgs

abstract:
  The ATLAS and CMS experiments have recently announced the discovery of a
Higgs-like resonance with mass close to 125 GeV. Overall, the data is
consistent with a Standard Model (SM)-like Higgs boson. Such a particle may
arise in the minimal supersymmetric extension of the SM with average stop
masses of the order of the TeV scale and a sizable stop mixing parameter. In
this article we discuss properties of the SM-like Higgs production and decay
rates induced by the possible presence of light staus and light stops. Light
staus can affect the decay rate of the Higgs into di-photons and, in the case
of sizable left-right mixing, induce an enhancement in this production channel
up to $\sim$ 50% of the Standard Model rate. Light stops may induce sizable
modifications of the Higgs gluon fusion production rate and correlated
modifications to the Higgs diphoton decay. Departures from SM values of the
bottom-quark and tau-lepton couplings to the Higgs can be obtained due to Higgs
mixing effects triggered by light third generation scalar superpartners. We
describe the phenomenological implications of light staus on searches for light
stops and non-standard Higgs bosons. Finally, we discuss the current status of
the search for light staus produced in association with sneutrinos, in final
states containing a $W$ gauge boson and a pair of $\tau$s.


title:
To Tilt or Not To Tilt: Discrete Gauge Symmetries in Global Intersecting
  D-Brane Models

abstract:
  Discrete gauge symmetries in global intersecting D-brane models constrain the
exact form of the perturbative as well as non-perturbative superpotential. We
derive the complete set of conditions on the existence of discrete Zn gauge
symmetries on toroidal orbifolds, T6/Z(N) and T6/Z(2)xZ(2M}, with fractional or
rigid D6-branes on tilted tori, for which global models of particle physics are
known. Several examples of global left-right symmetric and Pati-Salam models
are presented. Some discrete `stringy' Zn symmetries are trivial from the field
theory point of view, while others have not been identified before.


title: Imaging Cooper Pairing of Heavy Fermions in CeCoIn5

abstract:
  The Cooper pairing mechanism of heavy-fermion superconductors, while long
hypothesized as due to spin fluctuations, has not been determined. It is the
momentum space (k-space) structure of the superconducting energy gap delta(k)
that encodes specifics of this pairing mechanism. However, because the energy
scales are so low, it has not been possible to directly measure delta(k) for
any heavy-fermion superconductor. Bogoliubov quasiparticle interference (QPI)
imaging, a proven technique for measuring the energy gaps of high-Tc
superconductors, has recently been proposed as a new method to measure delta(k)
in heavy-fermion superconductors, specifically CeCoIn5. By implementing this
method, we immediately detect a superconducting energy gap whose nodes are
oriented along k||(+-1, +-1)pi/a0 directions. Moreover, we determine the
complete k-space structure of the delta(k) of a heavy-fermion superconductor.
For CeCoIn5, this novel information includes: the complex band structure and
Fermi surface of the hybridized heavy bands, the fact that highest magnitude
delta(k) opens on a high-k band so that gap nodes occur at quite unanticipated
k-space locations, and that the Bogoliubov quasiparticle interference patterns
are most consistent with dx2-y2 gap symmetry. The availability of such
quantitative heavy band- and gap-structure data will be critical in identifying
the microscopic mechanism of heavy fermion superconductivity in this material,
and perhaps in general.


title:
Valence band offset, strain and shape effects on confined states in
  self-assembled InAs/InP and InAs/GaAs quantum dots

abstract:
  I present a systematic study of self-assembled InAs/InP and InAs/GaAs quantum
dots single particle and many body properties as a function of quantum
dot-surrounding matrix valence band offset. I use an atomistic, empirical
tight-binding approach and perform numerically demanding calculations for
half-million atom nanosystems. I demonstrate that the overall confinement in
quantum dots is a nontrivial interplay of two key factors: strain effects and
the valence band offset. I show that strain effects determine both the peculiar
structure of confined hole states of lens type InAs/GaAs quantum dots and the
characteristic ,,shell-like" structure of confined holes states in commonly
considered "low-strain" lens type InAs/InP quantum dot. I also demonstrate that
strain leads to single band-like behavior of hole states of disc type (,,indium
flushed") InAs/GaAs and InAs/InP quantum dots. I show how strain and valence
band offset affect quantum dot many-body properties: the excitonic fine
structure, an important factor for efficient entangled photon pair generation,
and the biexciton and charged excitons binding energies


title: Counterexamples to Kauffman's Conjectures on Slice Knots

abstract:
  In 1982 Louis Kauffman conjectured that if a knot in the 3-sphere is a slice
knot then on any Seifert surface for that knot there exists a homologically
essential simple closed curve of self-linking zero which is itself a slice
knot, or at least has Arf invariant zero. Since that time, considerable
evidence has been amassed in support of this conjecture. In particular, many
invariants that obstruct a knot from being a slice knot have been explictly
expressed in terms of invariants of such curves on the Seifert surface. We give
counterexamples to Kauffman's conjecture, that is, we exhibit (smoothly) slice
knots that admit (unique minimal genus) Seifert surfaces on which every
homologically essential simple closed curve of self-linking zero has non-zero
Arf invariant and non-zero signatures.


title: O-minimal structures: low arity versus generation

abstract:
  We show that an analogue of the Hilbert's Thirteenth Problem fails in the
real subanalytic setting.Namely we prove that, for any integer $n$, the
o-minimal structure generated by restricted analytic functions in $n$ variables
is strictly smaller than the structure of all global subanalytic sets, whereas
these two structures define the same subsets in $\mathbb R ^{n+1}$.


title:
Kosaki-Longo index and classification of charges in 2D quantum spin
  models

abstract:
  We consider charge superselection sectors of two-dimensional quantum spin
models corresponding to cone localisable charges, and prove that the number of
equivalence classes of such charges is bounded by the Kosaki-Longo index of an
inclusion of certain observable algebras. To demonstrate the power of this
result we apply the theory to the toric code on a 2D infinite lattice. For this
model we can compute the index of this inclusion, and conclude that there are
four distinct irreducible charges in this model, in accordance with the
analysis of the toric code model on compact surfaces. We also give a sufficient
criterion for the non-degeneracy of the charge sectors, in the sense that
Verlinde's matrix S is invertible.


title: Analysis of Remote Synchronization in Complex Networks

abstract:
  A novel regime of synchronization, called remote synchronization, where the
peripheral nodes form a phase synchronized cluster not including the hub, was
recently observed in star motifs. We show the existence of a more general
dynamical state of remote synchronization in arbitrary networks of coupled
oscillators. This state is characterized by the synchronization of pairs of
nodes that are not directly connected via a physical link or any sequence of
synchronized nodes. This phenomenon is almost negligible in networks of phase
oscillators as its underlying mechanism is the modulation of the amplitude of
those intermediary nodes between the remotely synchronized units. Our findings
thus show the ubiquity and robustness of these states and bridge the gap from
their recent observation in simple toy graphs to complex networks.


title:
Coupling and induced depinning of magnetic domain walls in adjacent spin
  valve nanotracks

abstract:
  The magnetostatic interaction between magnetic domain walls (DWs) in adjacent
nanotracks has been shown to produce strong inter-DW coupling and mutual
pinning. In this paper, we have used electrical measurements of adjacent
spin-valve nanotracks to follow the positions of interacting DWs. We show that
the magnetostatic interaction between DWs causes not only mutual pinning, as
observed till now, but that a travelling DW can also induce the depinning of
DWs in near-by tracks. These effects may have great implications for some
proposed high density magnetic devices (e.g. racetrack memory, DW logic
circuits, or DW-based MRAM).


title:
Effective Theory of Dark Matter Decay into Monochromatic Photons and its
  Implications: Constraints from Associated Cosmic-Ray Emission

abstract:
  We show that there exists only a quite limited number of higher dimensional
operators which can naturally lead to a slow decay of dark matter particles
into monochromatic photons. As each of these operators inevitably induces
decays into particles other than photons, we show that the gamma-lines it
induces are always accompanied by a continuum flux of cosmic rays. Hence
constraints on cosmic-ray fluxes imply constraints on the intensity of
gamma-lines and vice-versa. A comparison with up to date observational bounds
shows the possibilities to observe or exclude cosmic rays associated to
gamma-line emission, so that one could better determine the properties of the
DM particle, possibly discriminating between some of the operators.


title: Note on the Weierstrass Preparation Theorem in Quasianalytic Local Rings

abstract:
  Consider quasianalytic local rings of germs of smooth functions closed under
composition, implicit equation, and monomial division. We show that if the
Weierstrass Preparation Theorem holds in such a ring then all elements of it
are germs of analytic functions. .


title: Radial sine-Gordon kinks as sources of fast breathers

abstract:
  We consider radial sine-Gordon kinks in two, three and higher dimensions. A
full two dimensional simulation showing that azimuthal perturbations remain
small allows to reduce the problem to the one dimensional radial sine-Gordon
equation. We solve this equation on an interval $[r_0,r_1]$ and absorb all
outgoing radiation. Before collision the kink is well described by a simple law
derived from the conservation of energy. In two dimensions for $r_0 \le 2$, the
collision disintegrates the kink into a fast breather while for $r_0 \ge 4$ we
obtain a kink-breather meta-stable state where breathers are shed at each kink
"return". In three and higher dimensions $d$ a kink-pulson state appears for
small $r_0$. The three states then exist as shown by a study of the $(d,r_0)$
parameter space. On the application side, the kink disintegration opens the way
for new types of terahertz microwave generators.


title:
Amenable equivalence relations and the construction of ergodic averages
  for group actions

abstract:
  We present a general new method for constructing pointwise ergodic sequences
on countable groups, which is applicable to amenable as well as to non-amenable
groups and treats both cases on an equal footing. The principle underlying the
method is that both cases can be viewed as instances of the general ergodic
theory of amenable equivalence relations.


title: Revisiting the flocking transition using active spins

abstract:
  We consider an active Ising model in which spins both diffuse and align on
lattice in one and two dimensions. The diffusion is biased so that plus or
minus spins hop preferably to the left or to the right, which generates a
flocking transition at low temperature/high density. We construct a
coarse-grained description of the model that predicts this transition to be a
first-order liquid-gas transition in the temperature-density ensemble, with a
critical density sent to infinity. In this first-order phase transition, the
magnetization is proportional to the liquid fraction and thus varies
continuously. Using microscopic simulations, we show that this theoretical
prediction holds in 2d whereas the fluctuations alter the transition in 1d,
preventing for instance any spontaneous symmetry breaking.


title:
Tumbling through a landscape: Evidence of instabilities in
  high-dimensional moduli spaces

abstract:
  We argue that a generic instability afflicts vacua that arise in theories
whose moduli space has large dimension. Specifically, by studying theories with
multiple scalar fields we provide numerical evidence that for a generic local
minimum of the potential the usual semiclassical bubble nucleation rate, Gamma
= A e^{-B}, increases rapidly as function of the number of fields in the
theory. As a consequence, the fraction of vacua with tunneling rates low enough
to maintain metastability appears to fall exponentially as a function of the
moduli space dimension. We discuss possible implications for the landscape of
string theory. Notably, if our results prove applicable to string theory, the
landscape of metastable vacua may not contain sufficient diversity to offer a
natural explanation of dark energy.


title:
Probabilistic approach to the length-scale dependence of the effect of
  water hydrogen bonding on hydrophobic hydration

abstract:
  We present a probabilistic approach to water-water hydrogen bonding that
allows one to obtain an analytic expression for the number of bonds per water
molecule as a function of both its distance to a hydrophobic particle and
hydrophobe radius. This approach can be used in the density functional theory
(DFT) and computer simulations to examine particle size effects on the
hydration of particles and on their solvent-mediated interaction. For example,
it allows one to explicitly identify a water hydrogen bond contribution to the
external potential whereto a water molecule is subjected near a hydrophobe. The
DFT implementation of the model predicts the hydration free energy per unit
area of a spherical hydrophobe to be sharply sensitive to the hydropobe radius
for small radii and weakly sensitive thereto for large ones; this corroborates
the vision of the hydration of small and large length-scale particles as
occurring via different mechanisms. On the other hand, the model predicts that
the hydration of even apolar particles of small enough radii may become
thermodynamically favorable owing to the interplay of the energies of pairwise
(dispersion) water-water and water-hydrophobe interactions. This sheds light on
previous counterintuitive observations (both theoretical and simulational) that
two inert gas molecules would prefer to form a solvent-separated pair rather
than a contact one.


title: On Hofer Energy of J-holomorphic Curves for Asymptotically Cylindrical J

abstract:
  In this paper, we provide a bound for the generalized Hofer energy of
punctured $J$-holomorphic curves in almost complex manifolds with
asymptotically cylindrical ends. As an application, we prove a version of
Gromov's Monotonicity Theorem with multiplicity. Namely, for a closed
symplectic manifold $(M,\omega)$ with a compatible almost complex structure $J$
and a ball $B$ in $M,$ there exists a constant $\hbar>0,$ such that any
$J$-holomorphic curve $\tilde{u}$ passing through the center of $B$ for $k$
times (counted with multiplicity) with boundary mapped to $\partial B$ has
symplectic area $\int_{\tilde{u}^{-1}(B)}\tilde{u}^{*}\omega>k\hbar,$ where the
constant $\hbar$ depends only on $(M,\omega,J)$ and the radius of $B.$ As a
consequence, the number of times that any closed $J$-holomorphic curve in $M$
passes through a point is bounded by a constant depending only on
$(M,\omega,J)$ and the symplectic area of $\tilde{u}$. Here $J$ is any
$\omega-$compatible smooth almost complex structure on $M$. In particular, we
do not require $J$ to be integrable.


title:
Generalized Thompson Sampling for Sequential Decision-Making and Causal
  Inference

abstract:
  Recently, it has been shown how sampling actions from the predictive
distribution over the optimal action-sometimes called Thompson sampling-can be
applied to solve sequential adaptive control problems, when the optimal policy
is known for each possible environment. The predictive distribution can then be
constructed by a Bayesian superposition of the optimal policies weighted by
their posterior probability that is updated by Bayesian inference and causal
calculus. Here we discuss three important features of this approach. First, we
discuss in how far such Thompson sampling can be regarded as a natural
consequence of the Bayesian modeling of policy uncertainty. Second, we show how
Thompson sampling can be used to study interactions between multiple adaptive
agents, thus, opening up an avenue of game-theoretic analysis. Third, we show
how Thompson sampling can be applied to infer causal relationships when
interacting with an environment in a sequential fashion. In summary, our
results suggest that Thompson sampling might not merely be a useful heuristic,
but a principled method to address problems of adaptive sequential
decision-making and causal inference.


title:
The maximum on a random time interval of a random walk with long-tailed
  increments and negative drift

abstract:
  We study the asymptotics for the maximum on a random time interval of a
random walk with a long-tailed distribution of its increments and negative
drift. We extend to a general stopping time a result by Asmussen (1998),
simplify its proof, and give some converses.


title: Hyperbolicity of Hamiltonian formulations in General Relativity

abstract:
  Well-posedness of the initial (boundary) value problem is an essential
property, both of meaningful physical models and of numerical applications. To
prove well-posedness of wave-type equations their level of hyperbolicity is an
essential ingredient. We develop helpful tools and classify a large class of
Hamiltonian versions of Einstein's equations with live gauge conditions with
respect to their hyperbolicity. Finally we find a symmetric hyperbolic
Hamiltonian formulation that allows for gauge conditions which are similar to
the puncture gauge.


title:
A General Iterative Shrinkage and Thresholding Algorithm for Non-convex
  Regularized Optimization Problems

abstract:
  Non-convex sparsity-inducing penalties have recently received considerable
attentions in sparse learning. Recent theoretical investigations have
demonstrated their superiority over the convex counterparts in several sparse
learning settings. However, solving the non-convex optimization problems
associated with non-convex penalties remains a big challenge. A commonly used
approach is the Multi-Stage (MS) convex relaxation (or DC programming), which
relaxes the original non-convex problem to a sequence of convex problems. This
approach is usually not very practical for large-scale problems because its
computational cost is a multiple of solving a single convex problem. In this
paper, we propose a General Iterative Shrinkage and Thresholding (GIST)
algorithm to solve the nonconvex optimization problem for a large class of
non-convex penalties. The GIST algorithm iteratively solves a proximal operator
problem, which in turn has a closed-form solution for many commonly used
penalties. At each outer iteration of the algorithm, we use a line search
initialized by the Barzilai-Borwein (BB) rule that allows finding an
appropriate step size quickly. The paper also presents a detailed convergence
analysis of the GIST algorithm. The efficiency of the proposed algorithm is
demonstrated by extensive experiments on large-scale data sets.


title: Chaotic inflation in supergravity and cosmic string production

abstract:
  We describe a simple model of chaotic inflation in supergravity where one can
easily tune not only the basic cosmological parameters such as n_{s}, r, and
f_NL, but also a possible (subdominant) cosmic string contribution to the CMB
anisotropy.


title:
The deepest Herschel-PACS far-infrared survey: number counts and
  infrared luminosity functions from combined PEP/GOODS-H observations

abstract:
  We present results from the deepest Herschel-PACS (Photodetector Array Camera
and Spectrometer) far-infrared blank field extragalactic survey, obtained by
combining observations of the GOODS (Great Observatories Origins Deep Survey)
fields from the PACS Evolutionary Probe (PEP) and GOODS-Herschel key
programmes. We describe data reduction and the construction of images and
catalogues. In the deepest parts of the GOODS-S field, the catalogues reach
3-sigma depths of 0.9, 0.6 and 1.3 mJy at 70, 100 and 160 um, respectively, and
resolve ~75% of the cosmic infrared background at 100um and 160um into
individually detected sources. We use these data to estimate the PACS confusion
noise, to derive the PACS number counts down to unprecedented depths and to
determine the infrared luminosity function of galaxies down to LIR=10^11 Lsun
at z~1 and LIR=10^12 Lsun at z~2, respectively. For the infrared luminosity
function of galaxies, our deep Herschel far-infrared observations are
fundamental because they provide more accurate infrared luminosity estimates
than those previously obtained from mid-infrared observations. Maps and source
catalogues (>3-sigma) are now publicly released. Combined with the large wealth
of multi-wavelength data available for the GOODS fields, these data provide a
powerful new tool for studying galaxy evolution over a broad range of
redshifts.


title: Global Weyl modules for equivariant map algebras

abstract:
  Equivariant map algebras are Lie algebras of algebraic maps from a scheme (or
algebraic variety) to a target finite-dimensional Lie algebra (in the case of
the current paper, we assume the latter is a simple Lie algebra) that are
equivariant with respect to the action of a finite group. In the first part of
this paper, we define global Weyl modules for equivariant map algebras
satisfying a mild assumption. We then identify a commutative algebra A that
acts naturally on the global Weyl modules, which leads to a Weyl functor from
the category of A-modules to the category of modules for the equivariant map
algebra in question. These definitions extend the ones previously given for
generalized current algebras (i.e. untwisted map algebras) and twisted loop
algebras.
  In the second part of the paper, we restrict our attention to equivariant map
algebras where the group involved is abelian, acts on the target Lie algebra by
diagram automorphisms, and freely on (the set of rational points of) the
scheme. Under these additional assumptions, we prove that A is finitely
generated and the global Weyl module is a finitely generated A-module. We also
define local Weyl modules via the Weyl functor and prove that these coincide
with the local Weyl modules defined directly in a previous paper. Finally, we
show that A is the algebra of coinvariants of the analogous algebra in the
untwisted case.


title: On Random Sampling Auctions for Digital Goods

abstract:
  In the context of auctions for digital goods, an interesting random sampling
auction has been proposed by Goldberg, Hartline, and Wright [2001]. This
auction has been analyzed by Feige, Flaxman, Hartline, and Kleinberg [2005],
who have shown that it is 15-competitive in the worst case {which is
substantially better than the previously proven constant bounds but still far
from the conjectured competitive ratio of 4. In this paper, we prove that the
aforementioned random sampling auction is indeed 4-competitive for a large
class of instances where the number of bids above (or equal to) the optimal
sale price is at least 6. We also show that it is 4:68-competitive for the
small class of remaining instances thus leaving a negligible gap between the
lower and upper bound. We employ a mix of probabilistic techniques and dynamic
programming to compute these bounds.


title:
The Public Safety Broadband Network: A Novel Architecture with Mobile
  Base Stations

abstract:
  A nationwide interoperable public safety broadband network is being planned
by the United States government. The network will be based on long term
evolution (LTE) standards and use recently designated spectrum in the 700 MHz
band. The public safety network has different objectives and traffic patterns
than commercial wireless networks. In particular, the public safety network
puts more emphasis on coverage, reliability and latency in the worst case
scenario. Moreover, the routine public safety traffic is relatively light,
whereas when a major incident occurs, the traffic demand at the incident scene
can be significantly heavier than that in a commercial network. Hence it is
prohibitively costly to build the public safety network using conventional
cellular network architecture consisting of an infrastructure of stationary
base transceiver stations. A novel architecture is proposed in this paper for
the public safety broadband network. The architecture deploys stationary base
stations sparsely to serve light routine traffic and dispatches mobile base
stations to incident scenes along with public safety personnel to support heavy
traffic. The analysis shows that the proposed architecture can potentially
offer more than 75% reduction in terms of the total number of base stations
needed.


title:
Asymptotics for the maximum of a modulated random walk with heavy-tailed
  increments

abstract:
  We consider asymptotics for the maximum of a modulated random walk whose
increments $\xi_n^{X_n}$ are heavy-tailed. Of particular interest is the case
where the modulating process $X$ is regenerative. Here we study also the
maximum of the recursion given by $W_0=0$ and, for $n\ge1$,
$W_n=\max(0,W_{n-1}+\xi_n^{X_n})$


title: Solving Imperfect Information Games Using Decomposition

abstract:
  Decomposition, i.e. independently analyzing possible subgames, has proven to
be an essential principle for effective decision-making in perfect information
games. However, in imperfect information games, decomposition has proven to be
problematic. To date, all proposed techniques for decomposition in imperfect
information games have abandoned theoretical guarantees. This work presents the
first technique for decomposing an imperfect information game into subgames
that can be solved independently, while retaining optimality guarantees on the
full-game solution. We can use this technique to construct theoretically
justified algorithms that make better use of information available at run-time,
overcome memory or disk limitations at run-time, or make a time/space trade-off
to overcome memory or disk limitations while solving a game. In particular, we
present an algorithm for subgame solving which guarantees performance in the
whole game, in contrast to existing methods which may have unbounded error. In
addition, we present an offline game solving algorithm, CFR-D, which can
produce a Nash equilibrium for a game that is larger than available storage.


title: Entanglement Entropy Near Cosmological Singularities

abstract:
  We investigate the behavior of the entanglement entropy of a confining gauge
theory near cosmological singularities using gauge/gravity duality. As
expected, the coefficients of the UV divergent terms are given by simple
geometric properties of the entangling surface in the time-dependent
background. The finite (universal) part of the entanglement entropy either
grows without bound or remains bounded depending on the nature of the
singularity and entangling region. We also discuss a confinement/deconfinement
phase transition as signaled by the entanglement entropy.


title:
Subgraphs Satisfying MSO Properties on z-Topologically Orderable
  Digraphs

abstract:
  We introduce the notion of z-topological orderings for digraphs. We prove
that given a digraph G on n vertices admitting a z-topological order- ing,
together with such an ordering, one may count the number of subgraphs of G that
at the same time satisfy a monadic second order formula {\phi} and are the
union of k directed paths, in time f ({\phi}, k, z) * n^O(k*z) . Our result
implies the polynomial time solvability of many natural counting problems on
digraphs admitting z-topological orderings for constant values of z and k.
Concerning the relationship between z-topological orderability and other
digraph width measures, we observe that any digraph of directed path-width d
has a z- topological ordering for z <= 2d + 1. On the other hand, there are
digraphs on n vertices admitting a z-topological order for z = 2, but whose
directed path-width is {\Theta}(log n). Since graphs of bounded directed
path-width can have both arbitrarily large undirected tree-width and
arbitrarily large clique width, our result provides for the first time a
suitable way of partially trans- posing metatheorems developed in the context
of the monadic second order logic of graphs of constant undirected tree-width
and constant clique width to the realm of digraph width measures that are
closed under taking subgraphs and whose constant levels incorporate families of
graphs of arbitrarily large undirected tree-width and arbitrarily large clique
width.


title:
Virialisation-induced curvature as a physical explanation for dark
  energy

abstract:
  The geometry of the dark energy and cold dark matter dominated cosmological
model (LambdaCDM) is commonly assumed to be given by a
Friedmann-Lemaitre-Robertson-Walker (FLRW) metric, i.e. it assumes homogeneity
in the comoving spatial section. The homogeneity assumption fails most strongly
at (i) small distance scales and (ii) recent epochs, implying that the FLRW
approximation is most likely to fail at these scales. We use the virialisation
fraction to quantify (i) and (ii), which approximately coincide with each other
on the observational past light cone. For increasing time, the virialisation
fraction increases above 10% at about the same redshift (sim 1-3) at which
Omega_Lambda grows above 10% (approx 1.8). Thus, instead of non-zero
Omega_Lambda, we propose an approximate, general-relativistic correction to the
matter-dominated (Omega_m =1, Omega_Lambda=0), homogeneous metric (Einstein de
Sitter, EdS). A low-redshift effective matter-density parameter of
Omega_m^eff(0) = 0.26 pm 0.05 is inferred. Over redshifts 0 < z < 3, the
distance modulus of the virialisation-corrected EdS model approximately matches
the LambdaCDM distance modulus. This rough approximation assumes "old physics"
(general relativity), not "new physics". Thus, pending more detailed
calculations, we strengthen the claim that "dark energy" should be considered
as an artefact of emerging average curvature in the void-dominated Universe,
via a novel approach that quantifies the relation between virialisation and
average curvature evolution.


title:
Performance and Reliability Implications of Two Dimensional Shading in
  Monolithic Thin Film Photovoltaic Modules

abstract:
  We analyze the problem of partial shading in monolithically integrated thin
film photovoltaic (TFPV) modules, and explore how the shape and size of the
shadows dictate their performance and reliability. We focus on the aspects of
shading problem unique to monolithic TFPV, arising from thin long rectangular
series-connected cells, with partial shadows covering only a fraction of cell
area. We find that due to the cell shape, the unshaded portion of a partially
shaded cell experiences higher heat dissipation due to a redistribution of
voltages and currents in this two dimensional geometry. We also analyze the
effect of shadow size and orientation by considering several possible shading
scenarios. We find that thin edge shadows can cause potentially catastrophic
reverse bias damage, depending on their orientation. Finally, we show that
external bypass diodes cannot protect the individual cells from shadow-induced
reverse stress, but can improve the string output for larger shadows.


title:
An efficient implementation of two-component relativistic
  exact-decoupling methods for large molecules

abstract:
  We present an efficient algorithm for one- and two-component relativistic
exact-decoupling calculations. Spin-orbit coupling is thus taken into account
for the evaluation of relativistically transformed (one-electron) Hamiltonian.
As the relativistic decoupling transformation has to be evaluated with
primitive functions, the construction of the relativistic one-electron
Hamiltonian becomes the bottleneck of the whole calculation for large
molecules. For the established exact-decoupling protocols, a minimal matrix
operation count is established and discussed in detail. Furthermore, we apply
our recently developed local DLU scheme [J. Chem. Phys. 136 (2012) 244108] to
accelerate this step. With our new implementation two-component relativistic
density functional calculations can be performed invoking the
resolution-of-identity density-fitting approximation and (Abelian as well as
non-Abelian) point group symmetry to accelerate both the exact-decoupling and
the two-electron part. The capability of our implementation is illustrated at
the example of silver clusters with up to 309 atoms, for which the cohesive
energy is calculated and extrapolated to the bulk.

categories: physics.chem-ph cond-mat.mtrl-sci physics.atm-clus physics.comp-ph quant-ph


title: Design of Binary Network Codes for Multi-user Multi-way Relay Networks

abstract:
  We study multi-user multi-way relay networks where $N$ user nodes exchange
their information through a single relay node. We use network coding in the
relay to increase the throughput. Due to the limitation of complexity, we only
consider the binary multi-user network coding (BMNC) in the relay. We study
BMNC matrix (in GF(2)) and propose several design criteria on the BMNC matrix
to improve the symbol error probability (SEP) performance. Closed-form
expressions of the SEP of the system are provided. Moreover, an upper bound of
the SEP is also proposed to provide further insights on system performance.
Then BMNC matrices are designed to minimize the error probabilities.


title: Using carry-truncated addition to analyze add-rotate-xor hash algorithms

abstract:
  We introduce a truncated addition operation on pairs of N-bit binary numbers
that interpolates between ordinary addition mod 2^N and bitwise addition in
(Z/2Z)^N. We use truncated addition to analyze hash functions that are built
from the bit operations add, rotate, and xor, such as Blake, Skein, and
Cubehash. Any ARX algorithm can be approximated by replacing ordinary addition
with truncated addition, and we define a metric on such algorithms which we
call the {\bf sensitivity}. This metric measures the smallest approximation
agreeing with the full algorithm a statistically useful portion of the time (we
use 0.1%). Because truncated addition greatly reduces the complexity of the
non-linear operation in ARX algorithms, the approximated algorithms are more
susceptible to both collision and pre-image attacks, and we outline a potential
collision attack explicitly. We particularize some of these observations to the
Skein hash function.


title: Counting maps from curves to projective space via graph theory

abstract:
  In this (mostly) survey article, we give a synopsis of a number of results
relating to Brill--Noether theory on curves and metric graphs, together with
some speculations about the behavior of one-dimensional linear series on a
class of metric graphs that admit decompositions as triples of trees rooted on
a common vertex set.


title: Isometric actions on pseudo-Riemannian nilmanifolds

abstract:
  This work deals with the structure of the isometry group of pseudo-Riemannian
2-step nilmanifolds. We study the action by isometries of several groups and we
construct examples showing substantial differences with the Riemannain
situation; for instance the action of the nilradical of the isometry group does
not need to be transitive. For a nilpotent Lie group endowed with
left-invariant pseudo-Riemannian metric we study conditions for which the
subgroup of isometries fixing the identity element equals the subgroup of
isometric automorphisms. This set equality holds for pseudo-$H$-type groups.


title: Limited Attention and Centrality in Social Networks

abstract:
  How does one find important or influential people in an online social
network? Researchers have proposed a variety of centrality measures to identify
individuals that are, for example, often visited by a random walk, infected in
an epidemic, or receive many messages from friends. Recent research suggests
that a social media users' capacity to respond to an incoming message is
constrained by their finite attention, which they divide over all incoming
information, i.e., information sent by users they follow. We propose a new
measure of centrality --- limited-attention version of Bonacich's
Alpha-centrality --- that models the effect of limited attention on epidemic
diffusion. The new measure describes a process in which nodes broadcast
messages to their out-neighbors, but the neighbors' ability to receive the
message depends on the number of in-neighbors they have. We evaluate the
proposed measure on real-world online social networks and show that it can
better reproduce an empirical influence ranking of users than other popular
centrality measures.


title: BICM Performance Improvement via Online LLR Optimization

abstract:
  We consider bit interleaved coded modulation (BICM) receiver performance
improvement based on the concept of generalized mutual information (GMI).
Increasing achievable rates of BICM receiver with GMI maximization by proper
scaling of the log likelihood ratio (LLR) is investigated. While it has been
shown in the literature that look-up table based LLR scaling functions matched
to each specific transmission scenario may provide close to optimal solutions,
this method is difficult to adapt to time-varying channel conditions. To solve
this problem, an online adaptive scaling factor searching algorithm is
developed. Uniform scaling factors are applied to LLRs from different bit
channels of each data frame by maximizing an approximate GMI that characterizes
the transmission conditions of current data frame. Numerical analysis on
effective achievable rates as well as link level simulation of realistic mobile
transmission scenarios indicate that the proposed method is simple yet
effective.


title:
Glassy states and superrelaxation in populations of coupled phase
  oscillators

abstract:
  Large networks of coupled oscillators appear in many branches of science, so
that the kinds of phenomena they exhibit are not only of intrinsic interest but
also of very wide importance. In 1975, Kuramoto proposed an analytically
tractable model to describe such systems, which has since been successfully
applied in many contexts and remains a subject of intensive research. Some
related problems, however, remain unclarified for decades, such as the
properties of the oscillator glass state discovered by Daido in 1992. Here we
present a detailed analysis of a very general form of the Kuramoto model. In
particular, we find the conditions when it can exhibit glassy behavior, which
represents a kind of synchronous disorder in the present case. Furthermore, we
discover a new and intriguing phenomenon that we refer to as {\it
superrelaxation} where, for a class of parameter distributions, the oscillators
feel no interaction at all during relaxation to incoherence, a phenomenon
reminiscent of superfluidity or superconductivity. Our findings offer the
possibility of creating glassy states and observing superrelaxation in real
systems, thus paving the way to a cascade of applications and further research
in the field.


title: Characteristic classes of singular toric varieties

abstract:
  In this paper we compute the motivic Chern classes and homology Hirzebruch
characteristic classes of (possibly singular) toric varieties, which in the
complete case fit nicely with a generalized Hirzebruch-Riemann-Roch theorem. As
special cases, we obtain new (or recover well-known) formulae for the
Baum-Fulton-MacPherson Todd (or MacPherson-Chern) classes of toric varieties,
as well as for the Thom-Milnor L-classes of simplicial projective toric
varieties. We present two different perspectives for the computation of these
characteristic classes of toric varieties. First, we take advantage of the
torus-orbit decomposition and the motivic properties of the motivic Chern and
resp. homology Hirzebruch classes to express the latter in terms of dualizing
sheaves and resp. the (dual) Todd classes of closures of orbits. This method
even applies to torus-invariant subspaces of a given toric variety. The
obtained formula is then applied to weighted lattice point counting in lattice
polytopes and their subcomplexes, yielding generalized Pick-type formulae.
Secondly, in the case of simplicial toric varieties, we compute our
characteristic classes by using the Lefschetz-Riemann-Roch theorem of
Edidin-Graham in the context of the geometric quotient description of such
varieties. In this setting, we define mock Hirzebruch classes of simplicial
toric varieties and investigate the difference between the (actual) homology
Hirzebruch class and the mock Hirzebruch class. We show that this difference is
localized on the singular locus, and we obtain a formula for it in which the
contribution of each singular cone is identified explicitly. Finally, the two
methods of computing characteristic classes are combined for proving several
characteristic class formulae originally obtained by Cappell and Shaneson in
the early 1990s.


title: Topological Entanglement Entropy with a Twist

abstract:
  Defects in topologically ordered models have interesting properties that are
reminiscent of the anyonic excitations of the models themselves. For example,
dislocations in the toric code model are known as twists and possess properties
that are analogous to Ising anyons. We strengthen this analogy by using the
topological entanglement entropy as a diagnostic tool to identify properties of
both defects and excitations in the toric code. Specifically, we show, through
explicit calculation, that the toric code model including twists and dyon
excitations has the same quantum dimensions, the same total quantum dimension,
and the same fusion rules as an Ising anyon model.


title:
Parabolic equations in simple convex polytopes with time irregular
  coefficients

abstract:
  We prove the $W^{1,2}_p$-estimate and solvability for the Dirichlet problem
of second-order parabolic equations in simple convex polytopes with time
irregular coefficients, when $p\in (1,2]$. We also consider the corresponding
Neumann problem in a half space when $p\in [2,\infty)$. Similar results are
obtained for equations in a half space with coefficients which are measurable
in a tangential direction and have small mean oscillations in the other
directions.


title: Inertial manifolds and finite-dimensional reduction for dissipative PDEs

abstract:
  These notes are devoted to the problem of finite-dimensional reduction for
parabolic PDEs. We give a detailed exposition of the classical theory of
inertial manifolds as well as various attempts to generalize it based on the
so-called Man\'e projection theorems. The recent counterexamples which show
that the underlying dynamics may be in a sense infinite-dimensional if the
spectral gap condition is violated as well as the discussion on the most
important open problems are also included.


title: Phase retrieval from power spectra of masked signals

abstract:
  In diffraction imaging, one is tasked with reconstructing a signal from its
power spectrum. To resolve the ambiguity in this inverse problem, one might
invoke prior knowledge about the signal, but phase retrieval algorithms in this
vein have found limited success. One alternative is to create redundancy in the
measurement process by illuminating the signal multiple times, distorting the
signal each time with a different mask. Despite several recent advances in
phase retrieval, the community has yet to construct an ensemble of masks which
uniquely determines all signals and admits an efficient reconstruction
algorithm. In this paper, we leverage the recently proposed polarization method
to construct such an ensemble. We also present numerical simulations to
illustrate the stability of the polarization method in this setting. In
comparison to a state-of-the-art phase retrieval algorithm known as PhaseLift,
we find that polarization is much faster with comparable stability.


title: Subconvexity for the Rankin-Selberg L-function in both levels

abstract:
  In this paper, we obtain a subconvexity result for the Rankin-Selberg
L-function in both levels. The new feature in this result is applying an
amplification method of Duke-Friedlander-Iwaniec to a double
Petersson-Kuznetsov trace formula.
  As the trace formula ranges over all the $GL_2$ spectrum, this subconvexity
result is unconditional of which Hecke eigenforms are chosen in the
Rankin-Selberg L-function.


title: Surface defects, the superconformal index and q-deformed Yang-Mills

abstract:
  Recently a prescription to compute the four-dimensional N = 2 superconformal
index in the presence of certain BPS surface defects has been given. These
surface defects are labelled by symmetric representations of SU(N). In the
present paper we give a prescription to compute the superconformal index in the
presence of surface defects labelled by arbitrary representations of SU(N).
Furthermore, we extend the dictionary between the N = 2 superconformal
Schur-index and correlators of q-deformed Yang-Mills to incorporate such
surface defects.


title: Medical Process Modeling: an Artifact-Centric Approach

abstract:
  In this position paper we argue that just as traditional business process
modeling has been adopted to deal with clinical pathways, also the
artifact-centric process modeling technique may be successfully used to model
various kinds of medical processes: physiological processes, disease behavior
and treatment processes. We also discuss how a proposed approach may be used to
deal with an interplay of all the processes a patient is subject to and what
are the queries that might be imposed over an overall patient model.


title:
Nontriviality in Black Hole Thermodynamics: towards physically and
  mathematically rigorous foundation as phenomenology

abstract:
  Comparing black hole thermodynamics with the axiomatic formulation of
thermodynamics for laboratory systems, it is found that some basic assumptions
(required by experimental facts) in laboratory thermodynamics do not hold for
black hole thermodynamics. Hence, at present, it is not obvious whether black
hole thermodynamics retains some crucial theorems of laboratory thermodynamics
(e.g. Carnot's theorem, increase of entropy by arbitrary adiabatic process, and
uniqueness of entropy) whose proofs use the basic assumptions which do not hold
for black holes. This paper aims to clarify such nontriviality in black hole
thermodynamics, and propose a suitable set of basic assumptions in black hole
thermodynamics, which are regarded as the rigorous foundation of black hole
thermodynamics as phenomenology.


title: He I Vector Magnetometry of Field Aligned Superpenumbral Fibrils

abstract:
  Atomic-level polarization and Zeeman effect diagnostics in the neutral helium
triplet at 10830 angstroms in principle allow full vector magnetometry of
fine-scaled chromospheric fibrils. We present high-resolution
spectropolarimetric observations of superpenumbral fibrils in the He I triplet
with sufficient polarimetric sensitivity to infer their full magnetic field
geometry. He I observations from the Facility Infrared Spectropolarimeter
(FIRS) are paired with high-resolution observations of the Halpha 6563
angstroms and Ca II 8542 angstroms spectral lines from the Interferometric
Bidimensional Spectrometer (IBIS) from the Dunn Solar Telescope in New Mexico.
Linear and circular polarization signatures in the He I triplet are measured
and described, as well as analyzed with the advanced inversion capability of
the "Hanle and Zeeman Light" (HAZEL) modeling code. Our analysis provides
direct evidence for the often assumed field alignment of fibril structures. The
projected angle of the fibrils and the inferred magnetic field geometry align
within an error of plus or minus 10 degrees. We describe changes in the
inclination angle of these features that reflect their connectivity with the
photospheric magnetic field. Evidence for an accelerated flow (approx 40 m/s^2)
along an individual fibril anchored at its endpoints in the strong sunspot and
weaker plage in part supports the magnetic siphon-flow mechanism's role in the
inverse Evershed effect. However, the connectivity of the outer endpoint of
many of the fibrils cannot be established.


title:
A short proof of the congruence representation theorem for semimodular
  lattices

abstract:
  In a 1998 paper with H. Lakser, the authors proved that every finite
distributive lattice $D$ can be represented as the congruence lattice of a
finite \emph{semimodular lattice}.
  Some ten years later, the first author and E. Knapp proved a much stronger
result, proving the representation theorem for \emph{rectangular lattices}.
  In this note we present a short proof of these results.


title:
Spectral evidence of a ghostly transition: Theory of NMR 1/T_1
  relaxation in a quantum spin nematic in applied magnetic field

abstract:
  There is now strong theoretical evidence that a wide range of frustrated
magnets should support quantum spin-nematic order in applied magnetic field.
Nonetheless, the fact that spin-nematic order does not break time-reversal
symmetry makes it very difficult to detect in experiment. In this article, we
continue the theme begun in [Phys. Rev. B 88, 184430 (2013)], of exploring how
spin-nematic order reveals itself in the spectrum of spin excitations. Building
on an earlier analysis of inelastic neutron scattering [Phys. Rev. B 91, 174402
(2015)], we show how the NMR 1/T_1 relaxation rate could be used to identify a
spin-nematic state. We emphasise the characteristic, universal features of
1/T_1, using a symmetry-based description of the spin-nematic order parameter
and its fluctuations.Turning to the specific case of spin-1/2 frustrated
ferromagnets, we show that the signal from competing spin-wave excitations can
be suppressed through a judicious choice of nuclear site and field direction.
As a worked example, we show how P NMR in the square-lattice frustrated
ferromagnet BaCdVO(PO_4)_2 is sensitive to spin-nematic order.


title:
Diagnosing the time-dependence of active region core heating from the
  emission measure: II. Nanoflare trains

abstract:
  The time-dependence of heating in solar active regions can be studied by
analyzing the slope of the emission measure distribution cool-ward of the peak.
In a previous study we showed that low-frequency heating can account for 0% to
77% of active region core emission measures. We now turn our attention to
heating by a finite succession of impulsive events for which the timescale
between events on a single magnetic strand is shorter than the cooling
timescale. We refer to this scenario as a "nanoflare train" and explore a
parameter space of heating and coronal loop properties with a hydrodynamic
model. Our conclusions are: (1) nanoflare trains are consistent with 86% to
100% of observed active region cores when uncertainties in the atomic data are
properly accounted for; (2) steeper slopes are found for larger values of the
ratio of the train duration $\Delta_H$ to the post-train cooling and draining
timescale $\Delta_C$, where $\Delta_H$ depends on the number of heating events,
the event duration and the time interval between successive events ($\tau_C$);
(3) $\tau_C$ may be diagnosed from the width of the hot component of the
emission measure provided that the temperature bins are much smaller than 0.1
dex; (4) the slope of the emission measure alone is not sufficient to provide
information about any timescale associated with heating - the length and
density of the heated structure must be measured for $\Delta_H$ to be uniquely
extracted from the ratio $\Delta_H/\Delta_C$.


title:
Uncertainty relations for MUBs and SIC-POVMs in terms of generalized
  entropies

abstract:
  We formulate uncertainty relations for mutually unbiased bases and symmetric
informationally complete measurements in terms of the R\'{e}nyi and Tsallis
entropies. For arbitrary number of mutually unbiased bases in a
finite-dimensional Hilbert space, we give a family of Tsallis $\alpha$-entropic
bounds for $\alpha\in(0;2]$. Relations in a model of detection inefficiences
are obtained. In terms of R\'{e}nyi's entropies, lower bounds are given for
$\alpha\in[2;\infty)$. State-dependent and state-independent forms of such
bounds are both given. Uncertainty relations in terms of the min-entropy are
separately considered. We also obtain lower bounds in term of the so-called
symmetrized entropies. The presented results for mutually unbiased bases are
extensions of some bounds previously derived in the literature. We further
formulate new properties of symmetric informationally complete measurements in
a finite-dimensional Hilbert space. For a given state and any SIC-POVM, the
index of coincidence of generated probability distribution is exactly
calculated. Short notes are made on potential use of this result in
entanglement detection. Further, we obtain state-dependent entropic uncertainty
relations for a single SIC-POVM. Entropic bounds are derived in terms of the
R\'{e}nyi $\alpha$-entropies for $\alpha\in[2;\infty)$ and the Tsallis
$\alpha$-entropies for $\alpha\in(0;2]$. In the Tsallis formulation, a case of
detection inefficiences is briefly mentioned. For a pair of symmetric
informationally complete measurements, we also obtain an entropic bound of
Maassen-Uffink type.


title: Collisional and Radiative Processes in Optically Thin Plasmas

abstract:
  Most of our knowledge of the physical processes in distant plasmas is
obtained through measurement of the radiation they produce. Here we provide an
overview of the main collisional and radiative processes and examples of
diagnostics relevant to the microphysical processes in the plasma. Many
analyses assume a time-steady plasma with ion populations in equilibrium with
the local temperature and Maxwellian distributions of particle velocities, but
these assumptions are easily violated in many cases. We consider these
departures from equilibrium and possible diagnostics in detail.


title:
D-brane solitons and boojums in field theory and Bose-Einstein
  condensates

abstract:
  In certain field theoretical models, composite solitons consisting of a
domain wall and vortex lines attached to the wall have been referred to as
D-brane solitons. We show that similar composite solitons can be realized in
phase-separated two-component Bose-Einstein condensates. We discuss the
similarities and differences between topological solitons in the Abelian-Higgs
model and those in two-component Bose-Einstein condensates. Based on the
formulation of gauge theory, we introduce the "boojum charge" to characterize
the "D-brane soliton" in Bose-Einstein condensates.

categories: cond-mat.quant-gas cond-mat.supr-con hep-ph hep-th


title: Past and future of some universes

abstract:
  We consider a class of toy models where a spatially flat universe is filled
with a perfect fluid. The dynamics is found exactly for all these models. In
one family, the perfect fluid is of the phantom type and we find that the
universe is first contracting and then expanding while the dynamics is always
accelerated. In a second family, the universe is first in an accelerated
expansion stage, then in a decelerated expansion stage until it reaches a
turning point after which it contracts in a decelerated way (increasing
contraction rate) followed by another accelerated stage (decreasing contraction
rate). We also consider the possibility to embed this perfect fluid in a
realistic cosmology. The first family cannot be viable in a conventional big
bang universe and requires a rebound in the very early universe. The second
family is viable in the range $0<1+w_{DE,0}\lesssim 0.09$ for a spatially
closed universe with a curvature satisfying current bounds. Though many of the
models in this family cannot be distinguished today from a universe dominated
by a cosmological constant, the present accelerated expansion is transient and
these universes will reach a turning point in the future before entering a
contraction phase.


title: BarQL: Collaborating Through Change

abstract:
  Applications such as Google Docs, Office 365, and Dropbox show a growing
trend towards incorporating multi-user live collaboration functionality into
web applications. These collaborative applications share a need to efficiently
express shared state, and a common strategy for doing so is a shared log
abstraction. Extensive research efforts on log abstractions by the database,
programming languages, and distributed systems communities have identified a
variety of optimization techniques based on the algebraic properties of updates
(i.e., pairwise commutativity, subsumption, and idempotence). Although these
techniques have been applied to specific applications and use-cases, to the
best of our knowledge, no attempt has been made to create a general framework
for such optimizations in the context of a non-trivial update language. In this
paper, we introduce mutation languages, a low-level framework for reasoning
about the algebraic properties of state updates, or mutations. We define BarQL,
a general purpose state-update language, and show how mutation languages allow
us to reason about the algebraic properties of updates expressed in BarQ L .


title: A criterion for lattice supersymmetry: cyclic Leibniz rule

abstract:
  It is old folklore that the violation of Leibniz rule on a lattice is an
obstruction for constructing a lattice supersymmetric model. While it is still
true for full supersymmetry, we show that a slightly modified form of the
Leibniz rule, which we call cyclic Leibniz rule (CLR), is actually a criterion
for the existence of partial lattice supersymmetry. In one dimension, we find
sets of lattice difference operator and field multiplication smeared over
lattice which satisfy the CLR under some natural assumptions such as
translational invariance and locality. Thereby we construct a model of
supersymmetric lattice quantum mechanics without spoiling locality. The CLR
relation is coincident with the condition that the vanishing of the so-called
surface term in the construction by lattice Nicolai map. We can construct
superfield formalism with arbitrary superpotential. This also enables us to
apply safely a localization technique to our model, because the kinetic term
and the interaction terms of our model are independently invariant under the
supersymmetry transformation. A preliminary attempt in finding a solution for
the higher dimensional case is also discussed.


title:
In-plane optical spectroscopy study on FeSe epitaxial thin film grown on
  SrTiO$_3$ substrate

abstract:
  We perform in-plane optical spectroscopy measurement on (00l) FeSe thin-film
grown on SrTiO$_3$ substrate by pulsed laser deposition method. The study
indicates that the low frequency conductivity consists of two Drude components,
a broad one which takes up most of the spectral weight and a very narrow one
roughly below 100-150 \cm. The narrow Drude component locates at so low
frequencies that no such behavior was observed in iron pnictides. The overall
plasma frequency is found to be smaller than the FeAs based compounds,
suggesting a stronger correlation effect. Similar to iron pnictides, a
temperature-induced spectral weight transfer is observed for FeSe. However, the
relevant energy scale is lower. Additionally, different from a recent ARPES
measurement which revealed a spin density wave (SDW) order at low temperature
for FeSe thin films grown on SrTiO$_3$ substrate, no signature of the band
structure reconstruction arising from the formation of the SDW order is seen by
optical measurement in the thick FeSe films.


title:
Large Gain Stability of Extremum Seeking and Higher-Order Averaging
  Theory

abstract:
  Convergence of Extremum Seeking (ES) algorithms has been established in the
limit of small gains. Using averaging theory and contraction analysis, we
propose a framework for computing explicit bounds on the departure of the ES
scheme from its ideal dominant-order average dynamics. The bounds remain valid
for possibly large gains. They allow us to establish stability and estimate
convergence rates, and they open the way to selecting "optimal" finite gains
for the ES scheme.


title: Gravity-mediated holography in fluid dynamics

abstract:
  For any spherically symmetric black hole spacetime with an ideal fluid
source, we establish a dual fluid system on a hypersurface near the black hole
horizon. The dual fluid is incompressible and obeys Navier-Stokes equation
subject to some external force. The force term in the fluid equation consists
in two parts, one comes from the curvature of the hypersurface, the other comes
from the stress-energy of the bulk fluid.


title:
A distributed adaptive steplength stochastic approximation method for
  monotone stochastic Nash Games

abstract:
  We consider a distributed stochastic approximation (SA) scheme for computing
an equilibrium of a stochastic Nash game. Standard SA schemes employ
diminishing steplength sequences that are square summable but not summable.
Such requirements provide a little or no guidance for how to leverage
Lipschitzian and monotonicity properties of the problem and naive choices
generally do not preform uniformly well on a breadth of problems. While a
centralized adaptive stepsize SA scheme is proposed in [1] for the optimization
framework, such a scheme provides no freedom for the agents in choosing their
own stepsizes. Thus, a direct application of centralized stepsize schemes is
impractical in solving Nash games. Furthermore, extensions to game-theoretic
regimes where players may independently choose steplength sequences are limited
to recent work by Koshal et al. [2]. Motivated by these shortcomings, we
present a distributed algorithm in which each player updates his steplength
based on the previous steplength and some problem parameters. The steplength
rules are derived from minimizing an upper bound of the errors associated with
players' decisions. It is shown that these rules generate sequences that
converge almost surely to an equilibrium of the stochastic Nash game.
Importantly, variants of this rule are suggested where players independently
select steplength sequences while abiding by an overall coordination
requirement. Preliminary numerical results are seen to be promising.


title:
Odd-symmetry phase gratings produce optical nulls uniquely insensitive
  to wavelength and depth

abstract:
  I present the analysis of a new class of diffractive optical element, the
odd-symmetry phase grating, which creates wavelength- and depth-robust features
in its near-field diffraction pattern.


title:
Reading charge transport from spin dynamics on the surface of
  topological insulator

abstract:
  Resolving the conductance of the topological surface states (TSSs) from the
bulk contribution has been a great challenge for studying the transport
property of topological insulators. By developing a non-purturbative diffusion
equation that describes fully the spin-charge dynamics in the strong spin-orbit
coupling regime, we present a proposal to read the charge transport information
of TSSs from its spin dynamics which can be isolated from the bulk contribution
by time-resolved second harmonic generation pump-probe measurement. We
demonstrate the qualitatively different Dyaknov-Perel spin relaxation behavior
between the TSSs and the two-dimensional spin-orbit coupling electron gas. The
decay time of both in-plane and out-of-plane spin polarization is naturally
proved to be identical to the charge transport time. The out-of-plane spin
dynamics is shown to be in the experimentally reachable regime of the
femtosecond pump probe spectroscopy and thereby we suggest experiments to
detect the charge transport property of the TSSs from their unique spin
dynamics.


title: Equivariant Multiplicative Closure

abstract:
  This paper describes an issue that arises when inverting elements of the
homotopy groups of an equivariant commutative ring. Equivariant commutative
rings possess an enhanced multiplicative structure arising from the presence of
"indexed products" (products indexed by a set with a non-trivial action of the
group). The formation of the "multiplicative closure" of a set must be altered
in order to accomodate this structure, and the result of localizing an
equivariant commutative ring can have an unexpected homotopy type.


title:
Multilinear singular and fractional integral operators on weighted
  Morrey spaces

abstract:
  In this paper, we will study the boundedness properties of multilinear
Calderon--Zygmund operators and multilinear fractional integrals on products of
weighted Morrey spaces with multiple weights.


title:
Thallium 7p lifetimes derived from experimental data and ab initio
  calculations of scalar polarizabilities

abstract:
  Two different theoretical methods have been used to complete a new
calculation of polarizability in the thallium 6p_{1/2}, 7s, and 7p_{1/2}
states. The predictions of the two methods agree to within 1% for the 6p_{1/2}
and 7s states and 2% for 7p_{1/2} state. We find that the theoretical
expression for the 6p_{1/2} - 7s transition polarizability difference is
dominated (greater than 90% contribution) by mixing of the 7s state with the
7p_{1/2} and 7p_{3/2} states. By comparing the theoretical expression to an
existing Stark shift measurement [Doret et al., Phys. Rev. A 66, 052504
(2002)], new, highly-accurate values for the thallium 7p excited-state
lifetimes have been extracted. The scalar polarizability of the 7p_{1/2} state
is also computed, anticipating an experimental determination of this quantity,
which will then enable a high-precision determination of the
6d_{j}-7p_{j^{\prime}} transition rates and provide a benchmark test of the two
theoretical approaches in the near future.


title: The eighth moment of Dirichlet $L$-functions

abstract:
  We prove an asymptotic for the eighth moment of Dirichlet $L$-functions
averaged over primitive characters $\chi$ modulo $q$, over all moduli $q\leq Q$
and with a short average on the critical line, conditionally on GRH. We derive
the analogous result for the fourth moment of Dirichlet twists of GL(2)
L-functions. Our results match the moment conjectures in the literature; in
particular, the constant 24024 appears as a factor in the leading order term of
the eighth moment.


title: Purely infinite partial crossed products

abstract:
  Let (A,G,\alpha) be a partial dynamical system. We show that there is a
bijective correspondence between G-invariant ideals of A and ideals in the
partial crossed product A xr G provided the action is exact and residually
topologically free. Assuming, in addition, a technical condition---automatic
when A is abelian---we show that A xr G is purely infinite if and only if the
positive nonzero elements in A are properly infinite in A xr G. As an
application we verify pure infiniteness of various partial crossed products,
including realisations of the Cuntz algebras O_n, O_A, O_N, and O_Z as partial
crossed products.


title:
Localized Dimension Growth: A Convolutional Random Network Coding
  Approach to Managing Memory and Decoding Delay

abstract:
  We consider an \textit{Adaptive Random Convolutional Network Coding} (ARCNC)
algorithm to address the issue of field size in random network coding for
multicast, and study its memory and decoding delay performances through both
analysis and numerical simulations. ARCNC operates as a convolutional code,
with the coefficients of local encoding kernels chosen randomly over a small
finite field. The cardinality of local encoding kernels increases with time
until the global encoding kernel matrices at related sink nodes have full
rank.ARCNC adapts to unknown network topologies without prior knowledge, by
locally incrementing the dimensionality of the convolutional code. Because
convolutional codes of different constraint lengths can coexist in different
portions of the network, reductions in decoding delay and memory overheads can
be achieved. We show that this method performs no worse than random linear
network codes in terms of decodability, and can provide significant gains in
terms of average decoding delay or memory in combination, shuttle and random
geometric networks.


title:
$S^1$-equivariant local index and transverse index for non-compact
  symplectic manifolds

abstract:
  We define an $S^1$-equivariant index for non-compact symplectic manifolds
with Hamiltonian $S^1$-action. We use the perturbation by Dirac-type operator
along the $S^1$-orbits. We give a formulation and a proof of quantization
conjecture for this $S^1$-equivariant index. We also give comments on the
relation between our $S^1$-equivariant index and the index of transverse
elliptic operators.


title:
The clustering of galaxies in the SDSS-III Baryon Oscillation
  Spectroscopic Survey: single-probe measurements and the strong power of
  normalized growth rate on constraining dark energy

abstract:
  We present measurements of the anisotropic galaxy clustering from the Data
Release 9 (DR9) CMASS sample of the SDSS-III Baryon Oscillation Spectroscopic
Survey (BOSS). We analyze the broad-range shape of the monopole and quadrupole
correlation functions to obtain constraints, at the effective redshift $z=0.57$
of the sample, on the Hubble expansion rate $H(z)$, the angular-diameter
distance $D_A(z)$, the normalized growth rate $f(z)\sigma_8(z)$, the physical
matter density $\Omega_m h^2$, and the biased amplitude of matter fluctuation
b\sigma_8(z). We obtain {$H(0.57)$, $D_A(0.57)$, $f(0.57)\sigma_8(0.57)$,
$\Omega_m h^2$, $b\sigma_8(0.57)$} = {$87.6_{-6.8}^{+6.7}$, $1396\pm73$,
$0.126_{-0.010}^{+0.008}$, $1.19\pm0.14$, $0.428\pm0.066$} and their covariance
matrix as well. The parameters which are not well constrained by our of galaxy
clustering analysis are marginalized over with wide flat priors. Since no
priors from other data sets (i.e., CMB) are adopted and no dark energy models
are assumed, our results from BOSS CMASS galaxy clustering alone may be
combined with other data sets, i.e. CMB, SNe, lensing or other galaxy
clustering data to constrain the parameters of a given cosmological model. We
show that the major power on constraining dark energy from the anisotropic
galaxy clustering signal, as compared to the angular-averaged one (monopole),
arises from including the normalized growth rate $f(z)\sigma_8(z)$. In the case
of the wCDM cosmological model our single-probe CMASS constraints, combined
with CMB (WMAP9+SPT), yield a value for the dark energy equation of state
parameter of $w=-0.90\pm0.11$. Therefore, it is important to include
$f(z)\sigma_8(z)$ while investigating the nature of dark energy with current
and upcoming large-scale galaxy surveys.


title: Integrated multi vector vortex beam generator

abstract:
  A novel method to generate and manipulate vector vortex beams in an
integrated, ring resonator based geometry is proposed. We show numerically that
a ring resonator, with an appropriate grating, addressed by a vertically
displaced access waveguide emits a complex optical field. The emitted beam
possesses a specific polarization topology, and consequently a transverse
intensity profile and orbital angular momentum. We propose a combination of
several concentric ring resonators, addressed with different bus guides, to
generate arbitrary orbital angular momentum qudit states, which could
potentially be used for classical and quantum communications. Finally, we
demonstrate numerically that this device works as an orbital angular momentum
sorter with an average cross-talk of -10 dB between different orbital angular
momentum channels.


title:
Blow-up criteria of strong solutions to the Ericksen-Leslie system in
  $\Bbb R^3$

abstract:
  In this paper, we establish the local well-posedness and blow-up criteria of
strong solutions to the Ericksen-Leslie system in $\Bbb R^3$ for the well-known
Oseen-Frank model. The local existence of strong solutions to liquid crystal
flows is obtained by using the Ginzburg-Landau approximation approach to
guarantee the constraint that the direction vector of the fluid is of length
one. We establish four kinds of blow-up criteria, including (i) the Serrin
type; (ii) the Beal-Kato-Majda type; (iii) the mixed type, i.e., Serrin type
condition for one field and Beal-Kato-Majda type condition on the other one;
(iv) a new one, which characterizes the maximal existence time of the strong
solutions to the Ericksen-Leslie system in terms of Serrin type norms of the
strong solutions to the Ginzburg-Landau approximate system. Furthermore, we
also prove that the strong solutions of the Ginzburg-Landau approximate system
converge to the strong solution of the Ericksen-Leslie system up to the maximal
existence time.


title:
Emergence of superconductivity at 45 K by lanthanum and phosphorus
  co-doping of CaFe2As2

abstract:
  Co-doping of lanthanum and phosphorus in CaFe2As2 induces superconductivity
at 45 K. This superconducting transition temperature is higher than the 38 K
transition in Ba1-xKxFe2As2, which is the maximum found thus far among the 122
phases. Superconductivity with a substantial shielding volume fraction was
observed at 0.12 $\leq$ x $\leq$ 0.18 and y = 0.06 in Ca1-xLaxFe2(As1-yPy)2.
The superconducting phase of the present system seems to be not adjacent to an
antiferromagnetic phase.


title:
LHC diphoton and Z+photon Higgs signals in the Higgs triplet model with
  Y=0

abstract:
  We study the implications of the LHC diphoton and Z+photon Higgs signals on
the Higgs triplet model with Y=0. We discuss three different scenarios: (i) the
observed boson is the light Higgs boson $h$; (ii) it is the heavy Higgs boson
$H$; (iii) the observed signal is from the almost degenerate $h$ and $H$. We
find that the inclusive Higgs diphoton rates in the first two scenarios can be
enhanced or suppressed compared to the SM value, which can respectively fit the
ATLAS and CMS diphoton data within $1\sigma$ range. The inclusive $ZZ^*$ rates
are suppressed, which are outside $1\sigma$ range of ATLAS data and within
$1\sigma$ range of CMS data. Meanwhile, another CP-even Higgs boson production
rate can be suppressed enough not to be observed at the collider. For the third
scenario, the Higgs diphoton rate is suppressed, which is outside $1\sigma$
range of ATLAS data, and the $ZZ^*$ rate equals to SM value approximately. In
addition, we find that the two rates of $h\to \gamma\gamma$ and $h\to Z\gamma$
have the positive correlations for the three scenarios.


title:
Magnetoelectric Resonances and Predicted Microwave Diode Effect of
  Skyrmion Crystal in Multiferroic Chiral-Lattice Magnet

abstract:
  We theoretically discover that unique eigenmodes of skyrmion crystal (SkX)
are not only magnetically active to ac magnetic field (H^w) but also
electrically active to ac electric field (E^w) in a multiferroic chiral-lattice
magnet Cu2OSeO3, which amplifies the dynamical magnetoelectric coupling between
E^w and the spin texture. The resulting intense interference between their
electric and magnetic activation processes can lead to unprecedentedly large
diode effect on the microwave, i.e., its absorption by SkX changes up to ~20%
when the incident direction is reversed. Our results demonstrate that the
skyrmion can be a promising building block for microwave devices.


title: Mean Value Inequalities and Conditions to Extend Ricci Flow

abstract:
  This paper concerns conditions related to the first finite singularity time
of a Ricci flow solution on a closed manifold. In particular, we provide a
systematic approach to the mean value inequality method, suggested by N. Le and
F. He. We also display a close connection between this method and time slice
analysis of B. Wang. As an application, we prove several inequalities for a
Ricci flow solution on a manifold with nonnegative isotropic curvature.


title: Spin torque transistor revisited

abstract:
  This paper reports on the improvement of the differential current gain in the
spin-torque transistor based on two independent innovations, viz.the use of
magnetic insulators and the spin Hall effect. Since, except for a few examples,
spin transistors lack the current gain that is essential for many applications,
spintronics and magnetic information technology lack an essential functionality
compared to CMOS devices. Here, we show that negative differential resistance
and large differential gain is possible in a large region of parameter space of
the spin torque transistor. We also demonstrate that functionality is preserved
when the control part is replaced by a normal metal film with a large spin Hall
angle.


title:
Polarization of the neutron induced from hadronic weak interactions in
  the photo-disintegration of the deuteron

abstract:
  New observables with which we can study the two-nucleon weak interactions at
low energies are considered. In the breakup of the deuteron by photons,
polarization of outgoing neutrons can depend on the parity-violating component
of two-nucleon interactions. We express the parity-violating polarization in
general forms, and perform numerical calculations with a pionless effective
field theory. The theory has unknown parity-violating low energy constants, and
the results are expressed in linear combination of them. We discuss the results
and their implication to the understanding of the hadronic weak interactions.


title:
Equidistribution in Higher Codimension for Holomorphic Endomorphisms of
  $\mathbb{P}^k$

abstract:
  In this paper, we discuss the equidistribution phenomena for holomorphic
endomorphisms over $\mathbb{P}^k$ in the case of bidegree $(p,p)$ with $1<p<k$.
We prove that if $f:\mathbb{P}^k\to\mathbb{P}^k$ is a holomorphic endomorphism
of degree $d\geq 2$ and $T^p$ denotes the Green $(p,p)$-current associated with
$f$, then there exists a proper invariant analytic subset $E$ for $f$ such that
$d^{-pn}(f^n)^*(S)\to T^p$ exponentially fast in the current sense for every
positive closed $(p,p)$-current $S$ of mass 1 such that $S$ is smooth on $E$.


title:
The Jones vector as a spinor and its representation on the Poincar\'e
  sphere

abstract:
  It is shown that the two complex Cartesian components of the electric field
of a monochromatic electromagnetic plane wave, with a temporal and spatial
dependence of the form ${\rm e}^{{\rm i} (kz - \omega t)}$, form a SU(2) spinor
that corresponds to a tangent vector to the Poincar\'e sphere representing the
state of polarization and phase of the wave. The geometrical representation on
the Poincar\'e sphere of the effect of some optical filters is reviewed. It is
also shown that in the case of a partially polarized beam, the coherency matrix
defines two diametrically opposite points of the Poincar\'e sphere.


title:
Constraints on single-field inflation with WMAP, SPT and ACT data -- A
  last-minute stand before Planck

abstract:
  We constrain models of single field inflation with the pre-\textit{Planck}
CMB data. The data used here is the 9-year Wilkinson Microwave Anisotropy Probe
(\textit{WMAP}) data, South Pole Telescope (SPT) data and Atacama Cosmology
Telescope (ACT) data. By adding in running of spectral index parameter, we find
that the $\chi^2$ is improved by a factor of $\Delta \chi^2=8.44$, which
strongly indicates the preference of this parameter from current data. In
addition, we find that the running of spectral index $\alpha_s$ does not change
very much even if we switch to different pivot scales, which suggests that the
power law expansion of power spectrum is accurate enough till the 1st order
term. Furthermore, we find that the joint constraints on $r-n_{s}$ give very
tight constraints on single-field inflation models, and the models with power
law potential $\phi^{p}$ can only survive if $0.9 \lesssim p \lesssim 2.1$, so
a large class of inflation models have already been ruled out before
\textit{Planck} data. Finally, we use the $f_{NL}$ data to constrain the
non-trivial sound speed $c_s$. We find that the current constraint is dominated
by the power spectrum constraints which have some inconsistency with the
constraints from $f_{NL}$. This poses important questions of consistency
between power spectrum and bispectrum of \textit{WMAP} data.


title: Challenges with Automation in Digital Forensic Investigations

abstract:
  The use of automation in digital forensic investigations is not only a
technological issue, but also has political and social implications. This work
discusses some challenges with the implementation and acceptance of automation
in digital forensic investigation, and possible implications for current
digital forensic investigators. Current attitudes towards the use of automation
in digital forensic investigations are examined, as well as the issue of
digital investigators knowledge acquisition and retention. The argument is made
for a well planned, careful use of automation going forward that allows for a
more efficient and effective use of automation in digital forensic
investigations while at the same time attempting to improve the overall quality
of expert investigators. Targeting and carefully controlling automated
solutions for beginning investigators may improve the speed and quality of
investigations while at the same time letting expert digital investigators
spend more time utilizing expert level knowledge required in manual phases of
investigations. By considering how automated solutions are being implemented
into digital investigations, investigation unit managers can increase the
efficiency of their unit while at the same time maximizing their return on
investment for expert level digital investigator training.


title: Some relations between certain classes of analytic functions

abstract:
  In the present paper we introduce and studied two subclasses of multivalent
functions denoted by $\mathcal{M}^{\lambda}_{p,n}(\gamma;\beta)$ and
$\mathcal{N}^{\lambda}_{p,n}(\mu,\eta;\delta)$. Further, by giving specific
values of the parameters of our main results, we will find some connection
between these two classes, and moreover, several consequences of main results
are also discussed.


title:
Possible Constraints on the Density Dependence of the Nuclear Symmetry
  Energy from Quasiperiodic Oscillations in Soft Gamma Repeaters

abstract:
  We systematically examine the fundamental frequencies of shear torsional
oscillations in neutron star crusts in a manner that is dependent on the
parameter $L$ characterizing the poorly known density dependence of the
symmetry energy. The identification of the lowest quasiperiodic oscillation
(QPO) among the observed QPOs from giant flares in soft-gamma repeaters as the
$/ell=2$ fundamental torsional oscillations enables us to constrain the
parameter $L$ as $L/ge 47.4$ MeV, which is the most conservative restriction on
$L$ obtained in the present work that assumes that the mass and radius of the
flaring neutron stars range 1.4-1.8 $M_{/odot}$ and 10-14 km. Next, we identify
one by one a set of the low-lying frequencies observed in giant flares as the
fundamental torsional oscillations. The values of $L$ that can reproduce all
the observed frequencies in terms of the torsional oscillations coupled with a
part of dripped neutrons via entrainment effects are then constrained as 101.1
MeV $/le L /le$ 131.0 MeV. Alternatively, if only the second lowest frequency
observed in SGR 1806$-$20 has a different origin, one obtains relatively low
$L$ values ranging 58.0 MeV $/le L /le$ 85.3 MeV, which seem more consistent
with other empirical constraints despite large uncertainties.


title: Arc-transitive graphs of valency 8 have a semiregular automorphism

abstract:
  One version of the polycirculant conjecture states that every
vertex-transitive graph has a semiregular automorphism. We give a proof of the
conjecture in the arc-transitive case for graphs of valency 8, which was the
smallest open case.


title:
Strong Correlation Effects of A-site Ordered Perovskite CaCu3Ti4O12
  revealed by Angle-Resolved Photoemission Spectroscopy

abstract:
  We report angle-resolved photoemission spectroscopy (ARPES) results of A-site
ordered perovskite CaCu$_3$Ti$_4$O$_{12}$. We have observed the clear band
dispersions, which are shifted to the higher energy by 1.7 eV and show the band
narrowing around 2 eV in comparison with the local density approximation
calculations. In addition, the high energy multiplet structures of Cu 3$d^8$
final-states have been found around 8 - 13 eV. These results reveal that
CaCu$_3$Ti$_4$O$_{12}$ is a Mott-type insulator caused by the strong
correlation effects of the Cu 3$d$ electrons well hybridized with O 2$p$
states. Unexpectedly, there exist a very small spectral weight at the Fermi
level in the insulator phase, indicating the existence of isolated metallic
states.


title:
EndoTOFPET-US a Novel Multimodal Tool for Endoscopy and Positron
  Emission Tomography

abstract:
  The EndoTOFPET-US project aims to jointly exploit Time-Of-Flight Positron
Emission Tomography (TOFPET) and ultrasound endoscopy with a multi-modal
instrument for the development of new biomarkers for pancreas and prostate
oncology. The paper outlines the functionality of the proposed instrument and
the challenges for its realization. The high level of miniaturization and
integration poses strong demands to the fields of scintillating
crystallography, ultra-fast photon detection, highly integrated electronics and
system integration. Solutions are presented to obtain a coincidence time
resolution better than 200 ps and a spatial resolution of ~1 mm with an
asymmetric TOFPET detector. A tracking system with better than 1 mm spatial
resolution precision enables the online alignment of the system. The detector
design, the production and test status of the single detector


title: Suppression of epidemic outbreaks with heavy-tailed contact dynamics

abstract:
  We study the epidemic spreading process following contact dynamics with
heavy-tailed waiting time distributions. We show both analytically and
numerically that the temporal heterogeneity of contact dynamics can
significantly suppress the disease's transmissibility, hence the size of
epidemic outbreak, obstructing the spreading process. Furthermore, when the
temporal heterogeneity is strong enough, one obtains the vanishing
transmissibility for any finite recovery time and regardless of underlying
structure of contacts, the condition of which was derived.


title:
Asymptotics of the ground state energy of heavy molecules in
  self-generated magnetic field

abstract:
  We consider asymptotics of the ground state energy of heavy atoms and
molecules in the self-generatedl magnetic field. Namely, we consider $$
H=((D-A)\cdot\boldsymbol{\sigma})^2-V $$ with $$V=\sum_{1\le m\le M}
\frac{Z_m}{|x-y_m|}$$ and a corresponding Multiparticle Quantum Hamiltonian $$
\mathsf{H}=\sum_{1\le n\le N} H_{x_n} +\sum_{1\le n < n'\le N}|x_n-x_{n'}|^{-1}
$$ on the Fock space $\wedge _{1\le n\le N} L^2(\mathbb{R}^3, \mathbb{C}^2)$.
Here $A$ is a self-generated magnetic fiels. Then the ground state energy is
given by $$ \mathsf{E}(A)=\inf
\operatorname{Spec}(\mathsf{H})+\frac{1}{\alpha}\int |\nabla \times A|^2\,dx $$
where the last term is the energy of magnetic field. Under assumption $\alpha
Z\le \kappa^*$ (with a small constant $\kappa^*$) we study the ground State
Energy $$ \mathsf{E}^*=\inf _{A}\mathsf{E}(A). $$ We derive its asymptotics
including Scott, and Schwinger and Dirac corrections.
  We also consider related topics: an excessive negative charge, ionization
energy and excessive positive charge when atoms can still bind into molecules.


title: Compact Ultradense Objects in the Solar System

abstract:
  We describe properties and gravitational interactions of meteor-mass and
greater compact ultra dense objects with nuclear density or greater (CUDO s).
We discuss possible enclosure of CUDO s in comets, stability of these objects
on impact with the Earth and Sun and show that the hypothesis of a CUDO core
helps resolve issues challenging the understanding of a few selected cometary
impacts.


title:
Electronic Structure and Resonant X-ray Emission Spectra of Carbon
  Shells of Iron Nanoparticles

abstract:
  The electronic structure of carbon shells of carbon encapsulated iron
nanoparticles carbon encapsulated Fe@C has been studied by X-ray resonant
emission and X-ray absorption spectroscopy. The recorded spectra have been
compared to the density functional calculations of the electronic structure of
graphene. It has been shown that an Fe@C carbon shell can be represented in the
form of several graphene layers with Stone-Wales defects. The dispersion of
energy bands of Fe@C has been examined using the measured C Ka resonant X-ray
emission spectra.


title:
Spontaneous symmetry breaking and optimization of functional
  renormalization group

abstract:
  The requirement for the absence of spontaneous symmetry breaking in the d=1
dimension has been used to optimize the regulator dependence of functional
renormalization group equations in the framework of the sine-Gordon scalar
field theory. Results obtained by the optimization of this kind were compared
to those of the Litim-Pawlowski and the principle of minimal sensitivity
optimization scenarios. The optimal parameters of the compactly supported
smooth (CSS) regulator, which recovers all major types of regulators in
appropriate limits, have been determined beyond the local potential
approximation, and the Litim limit of the CSS was found to be the optimal
choice.