title: K\"all\'en-Lehmann spectroscopy for (un)physical degrees of freedom

abstract:
  We consider the problem of "measuring" the K\"all\'en-Lehmann spectral
density of a particle (be it elementary or bound state) propagator by means of
4d lattice data. As the latter are obtained from operations at (Euclidean
momentum squared) p^2>=0, we are facing the generically ill-posed problem of
converting a limited data set over the positive real axis to an integral
representation, extending over the whole complex p^2-plane. We employ a linear
regularization strategy, commonly known as the Tikhonov method with Morozov
discrepancy principle, with suitable adaptations to realistic data, e.g. with
unknown threshold. An important virtue over the (standard) maximum entropy
method is the possibility to also probe unphysical spectral densities, as, for
example, of a confined gluon. We apply our proposal here to "physical" mock
spectral data as a litmus test and then to the lattice SU(3) Landau gauge gluon
at zero temperature.


title: Full counting statistics of random transition-rate matrices

abstract:
  We study the full counting statistics of current of large open systems
through the application of random matrix theory to transition-rate matrices. We
develop a method for calculating the ensemble-averaged current-cumulant
generating functions based on an expansion in terms of the inverse system size.
We investigate how different symmetry properties and different counting schemes
affect the results.


title: Cuspidal quintics and surfaces with $p_g=0,$ $K^2=3$ and 5-torsion

abstract:
  If $S$ is a quintic surface in $\mathbb P^3$ with singular set $15$
$3$-divisible ordinary cusps, then there is a Galois triple cover $\phi:X\to S$
branched only at the cusps such that $p_g(X)=4,$ $q(X)=0,$ $K_X^2=15$ and
$\phi$ is the canonical map of $X$. We use computer algebra to search for such
quintics having a free action of $\mathbb Z_5$, so that $X/{\mathbb Z_5}$ is a
smooth minimal surface of general type with $p_g=0$ and $K^2=3$. We find two
different quintics, one of which is the Van der Geer--Zagier quintic, the other
is new.
  We also construct a quintic threefold passing through the $15$ singular lines
of the Igusa quartic, with $15$ cuspidal lines there. By taking tangent
hyperplane sections, we compute quintic surfaces with singular set $17\mathsf
A_2$, $16\mathsf A_2$, $15\mathsf A_2+\mathsf A_3$ and $15\mathsf A_2+\mathsf
D_4$.


title: VVV High Proper Motion Survey

abstract:
  Here we present survey of proper motion stars towards the Galactic Bulge and
an adjacent plane region base on VISTA-VVV data. The searching method based on
cross-matching photometric Ks-band CASU catalogs. The most interesting
discoveries are shown.


title: A design proposal of the reverse DNA polymerase (3'-5' direction)

abstract:
  DNA Polymerase is an enzyme that participates in the process of DNA
replication. In general, forward DNA polymerase moves along the template strand
in a 3'-5' direction, and the daughter strand is formed in a 5'-3' direction.
This paper theoretically analyzes the mechanism of forward DNA polymerase, and
gives the design proposal of a new reverse DNA polymerase (3'-5' direction).


title:
First observation of liquid-xenon proportional electroluminescence in
  THGEM holes

abstract:
  Radiation-induced proportional-electroluminescence UV signals, emitted from
the holes of a Thick Gas Electron Multiplier (THGEM) electrode immersed in
liquid xenon, were recorded with a PMT for the first time. Significant photon
yields were observed using a 0.4 mm thick electrode with 0.3 mm diameter holes;
at 2 kV across the THGEM the photon yield was estimated to be ~600 UV
photons/electron over 4pi This may pave the way towards the realization of
novel single-phase noble-liquid radiation detectors incorporating liquid
hole-multipliers (LHM); their concept is presented.


title:
Two-cocycles give a full nonlinear parameterization of the simplest 3--3
  relation

abstract:
  A parameterization of Grassmann-algebraic relations corresponding to the
Pachner move 3--3 is proposed. In these relations, each 4-simplex is assigned a
Grassmann weight depending on five anticommuting variables associated with its
3-faces. The weights are chosen to have the "simplest" form - a
Grassmann--Gaussian exponent or its analogue (satisfying a similar system of
differential equations). Our parameterization works for a Zariski open set of
such relations, looks relevant from the algebraic-topological viewpoint, and
reveals intriguing nonlinear relations between objects associated with
simplices of different dimensions.


title: Spectator charge splitting of directed flow in heavy ion collisions

abstract:
  We estimate the effect of the spectator charge on distortion of single
charged pion distributions as well as on azimuthal anisotropies in heavy ion
collisions. A large electromagnetic effect on directed flow $v_1$ is predicted
in good agreement with existing WA98 as well as RHIC data. This effect results
in a splitting of $v_1$ for positive and negative pions. Detailed analysis of
this phenomenon may provide new information on the collision dynamics.


title: Effect of laser polarization on QED cascading

abstract:
  Development of QED cascades in a standing electromagnetic wave for circular
and linear polarizations is simulated numerically with a 3D PIC-MC code. It is
demonstrated that for the same laser energy the number of particles produced in
a circularly polarized field is greater than in a linearly polarized field,
though the acquiring mean energy per particle is larger in the latter case. The
qualitative model of laser-assisted QED cascades is extended by including the
effect of polarization of the field. It turns out that cascade dynamics is
notably more complicated in the case of linearly polarized field, where
separation into the qualitatively different "electric" and "magnetic" regions
(where the electric field is stronger than the magnetic field and vice versa)
becomes essential. In the "electric" regions acceleration is suppressed and
moreover the high-energy electrons are even getting cooled by photon emission.
The volumes of the "electric" and "magnetic" regions evolve periodically in
time, and so does the cascade growth rate. In contrast to the linear
polarization the charged particles can be accelerated by circularly polarized
wave even in "magnetic" region. The "electric" and "magnetic" regions do not
evolve in time and cascade growth rate almost does not depend on time for
circular polarization.


title:
Oblique spin-flip reflection of relativistic electrons from a potential
  barrier

abstract:
  The Dirac equation is used to describe oblique spin-conserving and spin-flip
reflections of relativistic electrons from a one-dimensional potential barrier
in a vacuum. When an electron hits the barrier from an oblique direction, its
spin-up and spin-down states have different energies due to the spin-orbit
interaction and the fact that the system has a structural inversion asymmetry.
When the electron is reflected in an elastic spin-conserving process, incoming
and outgoing angles are the same. If an elastic reflection is a spin-flip
process, the outgoing angle is different from the incoming one. As a result, a
beam of incoming spin-polarized electrons is split after the reflection into
two beams. Angles and intensities of the reflected beams are calculated. Spin
splitting of energies for relativistic electrons due to the spin-orbit
interaction in an asymmetric quantum well is described.


title: Acoustophoretic Waltz: a Contactless Exothermal Reaction

abstract:
  The fluid dynamics video shows the acoustophoretic handling of a metal sodium
chunks and a water droplets before, during and after mixing. The violent
exothermal reaction between solid and liquid introduces an additional phase
(hydrogen gas). We developed a unique concept for using ultrasound to stably
levitated and move along a plane multiple objects in air, independently from
their electromagnetic nature and aspect ratio. This contactless material
handling can be extended to hazardous, chemical or radioactive samples.


title:
Coexistence of cluster spin glass and superconductivity in
  Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ for $0.060 \leq x \leq 0.071$

abstract:
  We present 75As nuclear magnetic resonance data from measurements of a series
of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ crystals with $0.00 \leq x \leq 0.075$ that
reveals the coexistence of frozen antiferromagnetic domains and
superconductivity for $0.060 \leq x \leq 0.071$. Although bulk probes reveal no
long range antiferromagnetic order beyond $x = 0.06$, we find that the local
spin dynamics reveal no qualitative change across this transition. The
characteristic domain sizes vary by more than an order of magnitude, reaching a
maximum variation at $x = 0.06$. This inhomogeneous glassy dynamics may be an
intrinsic response to the competition between superconductivity and
antiferromagnetism in this system.


title:
A Generalized Wolff's Ideal Theorem on Certain Subalgebras of $
  H^{\infty}(\mathbb{D}) $

abstract:
  We prove the generalized Wolff's Ideal Theorem on certain uniformly closed
subalgebras of $ H^{\infty}(\mathbb{D}) $ on which the Corona Theorem is
already known to hold.


title: The Fermi Function Beyond The Second Order Perturbation Theory

abstract:
  The Fermi function is historically derived from the Dirac equation or the
Schr\"odinger equation. However, we claim that the Fermi function should be
derived from quantum field theory. Then, we obtain the following results: (1)
We give the electromagnetic correction of the beta decay to the fourth order in
$\alpha/v$, where $v$ is the electron velocity. (2) Our result is consistent
with the ordinary non-relativistic Fermi function. (3) We give the iterated
integral representation of the Fermi function for arbitrary order in
$\alpha/v$. (4) This representation is related to the multiple L values, and
they enable us to calculate the amplitude in the algebraic approach.


title: The lattice of submodules of a multiplicity free module

abstract:
  In this paper we determine, under some mild restrictions, the lattice of
submodules $\gL$ of a module $M$ all of whose composition factors have
multiplicity one. Such a lattice is distributive, and hence determined by its
poset of down-sets $P$. We define a directed Ext graph $\Ext_\gL$ of $\gL$ and
show that if $\Ext_\gL$ is acyclic, then $\Ext_\gL$ determines $P$. The result
applies to multiplicity free indecomposable modules for finite dimensional
algebras with acyclic Ext graph. It also applies to some deformed Verma modules
which arise in the Jantzen sum formula basic classical simple Lie superalgebras
in the deformed case.


title:
Q-tensor continuum energies as limits of head-to-tail-symmetric spin
  systems

abstract:
  We consider a class of spin-type discrete systems and analyze their continuum
limit as the lattice spacing goes to zero. Under standard coerciveness and
growth assumptions together with an additional head-to-tail symmetry condition,
we observe that this limit can be conveniently written as a functional in the
space of $Q$-tensors. We further characterize the limit energy density in
several cases (both in 2 and 3 dimensions). In the planar case we also develop
a second-order theory and we derive gradient or concentration-type models
according to the chosen scaling.


title: Graviton resonances on two-field thick branes

abstract:
  This work presents new results about the graviton massive spectrum in
two-field thick branes. Analyzing the massive spectra with a relative
probability method we have firstly showed the presence of resonance structures
and obtained a connection between the thickness of the defect and the lifetimes
of such resonances. We obtain another interesting results considering the
degenerate Bloch brane solutions. In these thick brane models, we have the
emergence of a splitting effect controlled by a degeneracy parameter. When the
degeneracy constant tends to a critical value, we have found massive resonances
to the gravitational field indicating the existence of modes highly coupled to
the brane. We also discussed the influence of the brane splitting effect over
the resonance lifetimes.


title:
A Computational Model of Two Cognitive Transitions Underlying Cultural
  Evolution

abstract:
  We tested the computational feasibility of the proposal that open-ended
cultural evolution was made possible by two cognitive transitions: (1) onset of
the capacity to chain thoughts together, followed by (2) onset of contextual
focus (CF): the capacity to shift between a divergent mode of thought conducive
to 'breaking out of a rut' and a convergent mode of thought conducive to minor
modifications. These transitions were simulated in EVOC, an agent-based model
of cultural evolution, in which the fitness of agents' actions increases as
agents invent ideas for new actions, and imitate the fittest of their
neighbors' actions. Both mean fitness and diversity of actions across the
society increased with chaining, and even more so with CF, as hypothesized. CF
was only effective when the fitness function changed, which supports its
hypothesized role in generating and refining ideas.


title:
Three-gluon running coupling from lattice QCD at $N_f=2+1+1$: a
  consistency check of the OPE approach

abstract:
  We present a lattice calculation of the renormalized running coupling
constant in symmetric (MOM) and asymmetric ($\widetilde{\rm MOM}$) momentum
substraction schemes including $u$, $d$, $s$ and $c$ quarks in the sea. An
Operator Product Expansion dominated by the dimension-two $\langle A^2\rangle$
condensate is used to fit the running of the coupling. We argue that the
agreement in the predicted $\langle A^2\rangle$ condensate for both schemes is
a strong support for the validity of the OPE approach and the effect of this
non-gauge invariant condensate over the running of the strong coupling.


title: Pressures for geodesic flows of rank one manifolds

abstract:
  We study the geodesic flow on the unit tangent bundle of a rank one manifold
and we give conditions under which all classical definitions of pressure of a
H\"older continuous potential coincide. We provide a large deviation statement,
which allows to neglect (periodic) orbits that lack sufficient hyperbolic
behavior. Our results involve conditions on the potential, that take into
consideration its properties in the nonhyperbolic part of the manifold. We draw
some conclusions for the construction of equilibrium states.


title: Interplay of Rashba/Dresselhaus spin splittings

abstract:
  The paper reviews the interplay of Rashba/Dresselhaus spin splittings in
various two dimensional systems made of III-V, wurtzite and SiGe. We discuss
the symmetry aspects of the linear and cubic in electron wavevector spin
splitting in heterostructures prepared on (001)-, (110)-, (111)-, (113)-,
(112)-, and (013)-oriented substrates and address the requirements for
suppression of spin relaxation and realization of the persistent spin helix
state. In experimental part of the paper we overview experimental results on
the interplay of Rashba/Dresselhaus spin splittings probed by photogalvanic
spectroscopy: the method based on the phenomenological equivalence of the
linear-in-wavevector spin splitting and several photogalvanic phenomena.


title:
[CII] and 12CO(1-0) Emission Maps in HLSJ091828.6+514223: A Strongly
  Lensed Interacting System at z=5.24

abstract:
  We present Submillimeter Array (SMA) [CII] 158um and Jansky Very Large Array
(JVLA) $^{12}$CO(1-0) line emission maps for the bright, lensed, submillimeter
source at $z=5.2430$ behind Abell 773: HLSJ091828.6+514223 (HLS0918). We
combine these measurements with previously reported line profiles, including
multiple $^{12}$CO rotational transitions, [CI], water and [NII], providing
some of the best constraints on the properties of the interstellar medium (ISM)
in a galaxy at $z>5$. HLS0918 has a total far-infrared (FIR) luminosity
L_FIR(8-1000um) = (1.6$\pm$0.1)x10^14 L_sun/mu, where the total magnification
mu_total = 8.9$\pm$1.9, via a new lens model from the [CII] and continuum maps.
Despite a HyLIRG luminosity, the FIR continuum shape resembles that of a local
LIRG. We simultaneously fit all of the observed spectral line profiles, finding
four components which correspond cleanly to discrete spatial structures
identified in the maps. The two most redshifted spectral components occupy the
nucleus of a massive galaxy, with a source plane separation <1 kpc. The reddest
dominates the continuum map (de-magnified L_FIR = (1.1$\pm$0.2)x10^13 L_sun),
and excites strong water emission in both nuclear components via a powerful FIR
radiation field from the intense star formation. A third star-forming component
is most likely a region of a merging companion (dV ~ 500 km/s) exhibiting
generally similar gas properties. The bluest component originates from a
spatially distinct region, and photo-dissociation region (PDR) analysis
suggests that it is lower density, cooler and forming stars less vigorously
than the other components. Strikingly, it has very strong [NII] emission which
may suggest an ionized, molecular outflow. This comprehensive view of gas
properties and morphology in HLS0918 previews the science possible for a large
sample of high-redshift galaxies once ALMA attains full sensitivity.


title: Bethe-Salpeter scattering amplitude in Minkowski space

abstract:
  The off-mass shell scattering amplitude, satisfying the Bethe-Salpeter
equation for spinless particles in Minkowski space with the ladder kernel, is
computed for the first time.


title: Extending axions searches with a spherical TPC

abstract:
  We present the prospects for detection of KK-axions using a large volume
spherical TPC through natural decay to two gammas. The higher excited mass
states of this axion model allows to reach densities which could be detectable
by this method. We show the capability of this detector to detect 2-prong
events coming from rest-mass axion decays and we provide efficiencies obtained
under some gas mixtures and pressure conditions. The sensitivity limit of a
future experiment with existing detectors geometry has been estimated for the
case of zero background limit.


title: An edge-weighted hook formula for labelled trees

abstract:
  A number of hook formulas and hook summation formulas have previously
appeared, involving various classes of trees. One of these classes of trees is
rooted trees with labelled vertices, in which the labels increase along every
chain from the root vertex to a leaf. In this paper we give a new hook
summation formula for these (unordered increasing) trees, by introducing a new
set of indeterminates indexed by pairs of vertices, that we call edge weights.
This new result generalizes a previous result by F\'eray and Goulden, that
arose in the context of representations of the symmetric group via the study of
Kerov's character polynomials. Our proof is by means of a combinatorial
bijection that is a generalization of the Pr\"ufer code for labelled trees.


title:
Cyclicity in Dirichlet-type spaces and extremal polynomials II:
  functions on the bidisk

abstract:
  We study Dirichlet-type spaces $\mathfrak{D}_{\alpha}$ of analytic functions
in the unit bidisk and their cyclic elements. These are the functions $f$ for
which there exists a sequence $(p_n)_{n=1}^{\infty}$ of polynomials in two
variables such that $\|p_nf-1\|_{\alpha}\to 0$ as $n\to \infty$. We obtain a
number of conditions that imply cyclicity, and obtain sharp estimates on the
best possible rate of decay of the norms $\|p_nf-1\|_{\alpha}$, in terms of the
degree of $p_n$, for certain classes of functions using results concerning
Hilbert spaces of functions of one complex variable and comparisons between
norms in one and two variables.
  We give examples of polynomials with no zeros on the bidisk that are not
cyclic in $\mathfrak{D}_{\alpha}$ for $\alpha>1/2$ (including the Dirichlet
space); this is in contrast with the one-variable case where all non-vanishing
polynomials are cyclic in Dirichlet-type spaces that are not algebras
($\alpha\le 1$). Further, we point out the necessity of a capacity zero
condition on zero sets (in an appropriate sense) for cyclicity in the setting
of the bidisk, and conclude by stating some open problems.


title: Adiabatic quantum control hampered by entanglement

abstract:
  We study defects in adiabatic control of a quantum system caused by the
entanglement of the system with its environment. Such defects can be
assimilated to decoherence processes due to perturbative couplings between the
system and the environment. To analyse these effects, we propose a geometric
approach based on a field theory on the control manifold issued from the higher
gauge theory associated with the $C^*$-geometric phases. We study a
visualization method to analyse the defects of adiabatic control based on the
drawing of the field strengths of the gauge theory. To illustrate the present
methodology we consider the example of the atomic STIRAP (stimulated Raman
adiabatic passage) where the controlled atom is entangled with another atom. We
study the robustness of the STIRAP effect when the controlled atom is entangled
with another one.


title: Generating random graphs in biased Maker-Breaker games

abstract:
  We present a general approach connecting biased Maker-Breaker games and
problems about local resilience in random graphs. We utilize this approach to
prove new results and also to derive some known results about biased
Maker-Breaker games. In particular, we show that for
$b=o\left(\sqrt{n}\right)$, Maker can build a pancyclic graph (that is, a graph
that contains cycles of every possible length) while playing a $(1:b)$ game on
$E(K_n)$. As another application, we show that for $b=\Theta\left(n/\ln
n\right)$, playing a $(1:b)$ game on $E(K_n)$, Maker can build a graph which
contains copies of all spanning trees having maximum degree $\Delta=O(1)$ with
a bare path of linear length (a bare path in a tree $T$ is a path with all
interior vertices of degree exactly two in $T$).


title: A Clash-of-Symmetries Mechanism from Intersecting Domain-Wall Branes

abstract:
  We present a new Clash-of-Symmetries mechanism in the context of an
intersecting domain-wall brane model in 5+1-dimensional Minkowskian spacetime
recently proposed by the authors. This new application of the Dvali-Shifman
idea is designed for localizing gauge fields on a domain-wall intersection and
we employ it by adding a gauge group $G$ and giving the scalar fields which
form lump-like profiles gauge charges. These fields in turn break $G$ to two
different subgroups $H_{1}$ and $H_{2}$ on each domain wall, and the gauge
fields of these subgroups are taken to be localized to the respective walls by
the confinement dynamics of $G$. There is then a further breaking on the
domain-wall intersection to $H_{1}\cap{}H_{2}$ and gauge fields of this overlap
group can then be localized to the intersection if they belong inside
non-Abelian subgroups of both $H_{1}$ and $H_{2}$ which are spontaneously
broken on the intersection and confining in the 4+1D bulks of the respective
domain-wall branes. This mechanism has some similarities to the
Clash-of-Symmetries mechanism on a single domain wall except that in this case
$H_{1}$ and $H_{2}$ need not be isomorphic. We then give some interesting
examples of the mechanism in an SU(7) gauge theory, several of which result in
the localization of the Standard Model gauge group.


title: User Satisfaction in Competitive Sponsored Search

abstract:
  We present a model of competition between web search algorithms, and study
the impact of such competition on user welfare. In our model, search providers
compete for customers by strategically selecting which search results to
display in response to user queries. Customers, in turn, have private
preferences over search results and will tend to use search engines that are
more likely to display pages satisfying their demands.
  Our main question is whether competition between search engines increases the
overall welfare of the users (i.e., the likelihood that a user finds a page of
interest). When search engines derive utility only from customers to whom they
show relevant results, we show that they differentiate their results, and every
equilibrium of the resulting game achieves at least half of the welfare that
could be obtained by a social planner. This bound also applies whenever the
likelihood of selecting a given engine is a convex function of the probability
that a user's demand will be satisfied, which includes natural Markovian models
of user behavior.
  On the other hand, when search engines derive utility from all customers
(independent of search result relevance) and the customer demand functions are
not convex, there are instances in which the (unique) equilibrium involves no
differentiation between engines and a high degree of randomness in search
results. This can degrade social welfare by a factor of the square root of N
relative to the social optimum, where N is the number of webpages. These bad
equilibria persist even when search engines can extract only small (but
non-zero) expected revenue from dissatisfied users, and much higher revenue
from satisfied ones.


title:
Light-induced pitch transitions in photosensitive cholesteric liquid
  crystals: Effects of anchoring energy

abstract:
  We experimentally study how the cholesteric pitch, $P$, depends on the
equilibrium one, $P_0$, in planar liquid crystal (LC) cells with both strong
and semistrong anchoring conditions. The cholesteric phase was induced by
dissolution in the nematic LC the right-handed chiral dopant 7-DHC
(7-dehydrocholesterol, provitamin $D_3$) which transforms to left-handed
tachysterol under the action of UV irradiation at the wavelength of 254 nm. By
using the model of photoreaction kinetics we obtain dependencies of isomers
concentrations and thus the equilibrium pitch on UV irradiation dose. The
cholesteric pitch was measured as a function of irradiation time using the
polarimetry method. In this method, the pitch is estimated from the
experimental data on the irradiation time dependence of the ellipticity of
light transmitted through the LC cells. It is found that the resulting
dependence of the twist parameter, $2 D/P$ ($D$ is the cell thickness), on the
free twisting number parameter, $2 D/P_0$, shows the jump-like behaviour and
agrees well with the known theoretical results for the anchoring potential of
the Rapini-Papoular form.


title:
Anisotropic Weyl Fermions from Quasiparticle Excitation Spectrum of a 3D
  Fulde-Ferrell Superfluid

abstract:
  Weyl fermions, first proposed for describing massless chiral Dirac fermions
in particle physics, have not been observed yet in experiments. Recently, much
effort has been devoted to explore Weyl fermions around band touching points of
single particle energy dispersions in certain solid state materials (named
\textit{Weyl semimetals}), similar as graphene for Dirac fermions. Here we show
that such Weyl semimetals also exist in the quasiparticle excitation spectrum
of a three-dimensional (3D) spin-orbit coupled Fulde-Ferrell (FF) superfluid.
By varying Zeeman fields, the properties of Weyl fermions, such as their
creation and annihilation, number and position, as well as anisotropic linear
dispersions around band touching points, can be tuned. We study the
manifestation of anisotropic Weyl fermions in sound speeds of FF fermionic
superfluids, which are detectable in experiments.


title: Observation of $e^{+} e^{-} \to \gamma X(3872)$ at BESIII

abstract:
  With data samples collected with the BESIII detector operating at the BEPCII
storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process
$e^{+} e^{-} \to \gamma X(3872)$ is observed for the first time with a
statistical significance of $6.3\sigma$. The measured mass of the $X(3872)$ is
($3871.9\pm 0.7_{\rm stat.}\pm 0.2_{\rm sys.}$) MeV/$c^2$, in agreement with
previous measurements. Measurements of the product of the cross section
$\sigma[e^{+} e^{-} \to \gamma X(3872)]$ and the branching fraction
$\mathcal{B}[X(3872) \to \pi^{+} \pi^{-} J/\psi]$ at center-of-mass energies
4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are
consistent with expectations for the radiative transition process $Y(4260) \to
\gamma X(3872)$.


title: What am I? Supercooled droplet or ice?

abstract:
  In this fluid dynamics video we show the trick played by a supercooled liquid
water drop against a superhydrophobic surface. The water drop shows a double
personality, impacting onto the surface the first time while still in the
liquid state, and then re-impacting as a frozen ice crystal.


title: On the common Point Spectrum of pairs of Self-Adjoint Extensions

abstract:
  Given two different self-adjoint extensions of the same symmetric operator,
we analyse the intersection of their point spectra. Some simple examples are
provided.


title:
Implementation of van der Waals Density Functional Approach to the
  Spin-Polarized System: Interaction Potential between Oxygen Molecules

abstract:
  We propose a practical approach to spin-polarized systems within the van der
Waals density functional (vdW-DF). The method was applied to a gas phase oxygen
molecule and a parallel (H-type) pair of oxygen molecules. It was found that
vdW-DF improves the equilibrium distance and binding energy. In particular, one
type of vdW-DF can describe such systems reasonably well. The van der Waals
interaction has been confirmed to have an energy comparable to the magnetic
one, while emerging at a distance rather longer than the latter.


title:
The Energy Loss of a Heavy Quark Moving Through a General Fluid
  Dynamical Flow

abstract:
  We determine the most general form of the covariant drag force exerted on a
quark moving through a fluid dynamical flow. Up to first order in derivative
expansion, our general formula requires the specification of seven coefficient
functions. We use the perturbative method introduced in arXiv:1202.2737 and
find all these coefficients in the hydrodynamic regime of a $\mathcal{N}=4$ SYM
plasma. Having this general formula, we can obtain the rate of the energy and
momentum loss of a quark, namely the drag force, in a general flow. This result
makes it possible to perturbatively study the motion of heavy quarks moving
through the Bjorken flow up to first order in derivative expansion.


title:
Weak bisimulations for labelled transition systems weighted over
  semirings

abstract:
  Weighted labelled transition systems are LTSs whose transitions are given
weights drawn from a commutative monoid. WLTSs subsume a wide range of LTSs,
providing a general notion of strong (weighted) bisimulation. In this paper we
extend this framework towards other behavioural equivalences, by considering
semirings of weights. Taking advantage of this extra structure, we introduce a
general notion of weak weighted bisimulation. We show that weak weighted
bisimulation coincides with the usual weak bisimulations in the cases of
non-deterministic and fully-probabilistic systems; moreover, it naturally
provides a definition of weak bisimulation also for kinds of LTSs where this
notion is currently missing (such as, stochastic systems). Finally, we provide
a categorical account of the coalgebraic construction of weak weighted
bisimulation; this construction points out how to port our approach to other
equivalences based on different notion of observability.


title:
Supermassive black holes with high accretion rates in active galactic
  nuclei: I. First results from a new reverberation mapping campaign

abstract:
  We report first results from a large project to measure black hole (BH) mass
in high accretion rate active galactic nuclei (AGNs). Such objects may be
different from other AGNs in being powered by slim accretion disks and showing
saturated accretion luminosities, but both are not yet fully understood. The
results are part of a large reverberation mapping (RM) campaign using the 2.4-m
Shangri-La telescope at the Yunnan Observatory in China. The goals are to
investigate the gas distribution near the BH and the properties of the central
accretion disks, to measure BH mass and Eddington ratios, and to test the
feasibility of using such objects as a new type of cosmological candles. The
paper presents results for three objects, Mrk 335, Mrk 142 and IRAS F12397+3333
with H$\beta$ time lags relative to the 5100\AA\ continuum of
$10.6^{+1.7}_{-2.9}$, $6.4^{+0.8}_{-2.2}$ and $11.4^{+2.9}_{-1.9}$ days,
respectively. The corresponding BH masses are $(8.3_{-3.2}^{+2.6})\times
10^6M_{\odot}$, $(3.4_{-1.2}^{+0.5})\times 10^6M_{\odot}$ and
$(7.5_{-4.1}^{+4.3})\times 10^6M_{\odot}$, and the lower limits on the
Eddington ratios 0.6, 2.3, and 4.6 for the minimal radiative efficiency of
0.038. Mrk 142 and IRAS F12397+333 (extinction corrected) clearly deviate from
the currently known relation between H$\beta$ lag and continuum luminosity. The
three Eddington ratios are beyond the values expected in thin accretion disks
and two of them are the largest measured so far among objects with RM-based BH
masses. We briefly discuss implications for slim disks, BH growth and
cosmology.


title: Manganese abundances in Galactic bulge red giants

abstract:
  Manganese is mainly produced in type II SNe during explosive silicon burning,
in incomplete Si-burning regions, and depends on several nucleosynthesis
environment conditions, such as mass cut beween the matter ejected and falling
back onto the remnant, electron and neutron excesses, mixing fallback, and
explosion energy. Manganese is also produced in type Ia SNe. The aim of this
work is the study of abundances of the iron-peak element Mn in 56 bulge giants,
among which 13 are red clump stars. Four bulge fields along the minor axis are
inspected. The study of abundances of Mn-over-Fe as a function of metallicity
in the Galactic bulge may shed light on its production mechanisms.
High-resolution spectra were obtained using the FLAMES+UVES spectrograph on the
Very Large Telescope. The spectra were obtained within a program to observe 800
stars using the GIRAFFE spectrograph, together with the present UVES spectra.
We aim at identifying the chemical evolution of manganese, as a function of
metallicity, in the Galactic bulge. We find [Mn/Fe] ~-0.7 at [Fe/H]~-1.3,
increasing to a solar value at metallicities close to solar, and showing a
spread around -0.7<[Fe/H]<-0.2, in good agreement with other work on Mn in
bulge stars. There is also good agreement with chemical evolution models. We
find no clear difference in the behaviour of the four bulge fields. Whereas
[Mn/Fe] vs. [Fe/H] could be identified with the behaviour of the thick disc
stars, [Mn/O] vs. [O/H] has a behaviour running parallel, at higher
metallicities, compared to thick disc stars, indicating that the bulge
enrichment might have proceeded differently from that of the thick disk.


abstract:
  Challenges for precision measurements at the LHC are discussed and a proposal
how to move forward to overcome the LHC-specific precision brick-walls is
presented.


title:
Equivalence of gradient flows and entropy solutions for singular
  nonlocal interaction equations in 1D

abstract:
  We prove the equivalence between the notion of Wasserstein gradient flow for
a one-dimensional nonlocal transport PDE with attractive/repulsive Newtonian
potential on one side, and the notion of entropy solution of a Burgers-type
scalar conservation law on the other. The solution of the former is obtained by
spatially differentiating the solution of the latter. The proof uses an
intermediate step, namely the $L^2$ gradient flow of the pseudo-inverse
distribution function of the gradient flow solution. We use this equivalence to
provide a rigorous particle-system approximation to the Wasserstein gradient
flow, avoiding the regularization effect due to the singularity in the
repulsive kernel. The abstract particle method relies on the so-called
wave-front-tracking algorithm for scalar conservation laws. Finally, we provide
a characterization of the sub-differential of the functional involved in the
Wasserstein gradient flow.


title: Regular elliptic boundary-value problems in the extended Sobolev scale

abstract:
  We investigate an arbitrary regular elliptic boundary-value problem given in
a bounded Euclidean domain with infinitely smooth boundary. We prove that the
operator of the problem is bounded and Fredholm in appropriate pairs of
H\"ormander inner product spaces. They are parametrized with the help of an
arbitrary radial function RO-varying at infinity and form the extended Sobolev
scale. We establish a priori estimates for solutions to the problem and
investigate their local regularity on this scale. We find new sufficient
conditions for generalized partial derivatives of the solutions to be
continuous.


title: Subalgebras of the Fomin-Kirillov algebra

abstract:
  The Fomin-Kirillov algebra $\mathcal E_n$ is a noncommutative quadratic
algebra with a generator for every edge of the complete graph on $n$ vertices.
For any graph $G$ on $n$ vertices, we define $\mathcal E_G$ to be the
subalgebra of $\mathcal E_n$ generated by the edges of $G$. We show that these
algebras have many parallels with Coxeter groups and their nil-Coxeter
algebras: for instance, $\mathcal E_G$ is a free $\mathcal E_H$-module for any
$H\subseteq G$, and if $\mathcal E_G$ is finite-dimensional, then its Hilbert
series has symmetric coefficients. We determine explicit monomial bases and
Hilbert series for $\mathcal E_G$ when $G$ is a simply-laced finite Dynkin
diagram or a cycle, in particular showing that $\mathcal E_G$ is
finite-dimensional in these cases. We also present conjectures for the Hilbert
series of $\mathcal E_{\tilde{D}_n}$, $\mathcal E_{\tilde{E}_6}$, and $\mathcal
E_{\tilde{E}_7}$, as well as for which graphs $G$ on six vertices $\mathcal
E_G$ is finite-dimensional.


title: A parallel repetition theorem for entangled projection games

abstract:
  We study the behavior of the entangled value of two-player one-round
projection games under parallel repetition. We show that for any projection
game $G$ of entangled value 1-eps < 1, the value of the $k$-fold repetition of
G goes to zero as O((1-eps^c)^k), for some universal constant c\geq 1.
Previously parallel repetition with an exponential decay in $k$ was only known
for the case of XOR and unique games. To prove the theorem we extend an
analytical framework recently introduced by Dinur and Steurer for the study of
the classical value of projection games under parallel repetition. Our proof,
as theirs, relies on the introduction of a simple relaxation of the entangled
value that is perfectly multiplicative. The main technical component of the
proof consists in showing that the relaxed value remains tightly connected to
the entangled value, thereby establishing the parallel repetition theorem. More
generally, we obtain results on the behavior of the entangled value under
products of arbitrary (not necessarily identical) projection games. Relating
our relaxed value to the entangled value is done by giving an algorithm for
converting a relaxed variant of quantum strategies that we call "vector quantum
strategy" to a quantum strategy. The algorithm is considerably simpler in case
the bipartite distribution of questions in the game has good expansion
properties. When this is not the case, rounding relies on a quantum analogue of
Holenstein's correlated sampling lemma which may be of independent interest.
Our "quantum correlated sampling lemma" generalizes results of van Dam and
Hayden on universal embezzlement.


title:
Rigidity and height bounds for certain post-critically finite
  endomorphisms of projective space

abstract:
  The holomorphic endomorphism f of projective space is called post-critically
finite (PCF) if the forward image of the critical locus, under iteration of f,
has algebraic support (i.e., is a finite union of hypersurfaces). In the case
of dimension 1, a deep result of Thurston implies that there are no algebraic
families of PCF morphisms, other than a well-understood exceptional class known
as the flexible Lattes maps. This note proves a corresponding result in
arbitrary dimension, for a certain subclass of morphism. Specifically, we
restrict attention to morphisms f of degree at least two, with a totally
invariant hyperplane H, such that the restriction of f to H is the dth power
map in some coordinates. This condition defines a subvariety of the space of
coordinate-free endomorphisms of projective space (of a given dimension). We
prove that there are no families of PCF maps in this space, and derive several
related arithmetic results.


title:
Fermion space charge in narrow-band gap semiconductors, Weyl semimetals
  and around highly charged nuclei

abstract:
  The field of charged impurities in narrow-band gap semiconductors and Weyl
semimetals can create electron-hole pairs when the total charge $Ze$ of the
impurity exceeds a value $Z_{c}e$. The particles of one charge escape to
infinity, leaving a screening space charge. The result is that the observable
dimensionless impurity charge $Q_{\infty}$ is less than $Z$ but greater than
$Z_{c}$. There is a corresponding effect for nuclei with $Z >Z_{c} \approx
170$, however in the condensed matter setting we find $Z_{c} \simeq 10$.
Thomas-Fermi theory indicates that $Q_{\infty} = 0$ for the Weyl semimetal, but
we argue that this is a defect of the theory. For the case of a highly-charged
recombination center in a narrow band-gap semiconductor (or of a supercharged
nucleus), the observable charge takes on a nearly universal value. In Weyl
semimetals the observable charge takes on the universal value $Q_{\infty} =
Z_{c}$ set by the reciprocal of material's fine structure constant.


title: Asymmetric Gepner models in type II

abstract:
  We describe new four-dimensional type II compactifications with N=2
supersymmetry, based on asymmetric Gepner models for K3 x T^2. In more than
half of these models, all the K3 moduli are lifted, giving at low energies N=2
supergravity with the STU vector multiplets and no hypermultiplets.


title:
Finite Difference Schemes for Linear Stochastic Integro-Differential
  Equations

abstract:
  We study the rate of convergence of an explicit and an implicit-explicit
finite difference scheme for linear stochastic integro-differential equations
of parabolic type arising in non-linear filtering of jump-diffusion processes.
We show that the rate is of order one in space and order one-half in time.


title: Matrix Product States for Lattice Field Theories

abstract:
  The term Tensor Network States (TNS) refers to a number of families of states
that represent different ans\"atze for the efficient description of the state
of a quantum many-body system. Matrix Product States (MPS) are one particular
case of TNS, and have become the most precise tool for the numerical study of
one dimensional quantum many-body systems, as the basis of the Density Matrix
Renormalization Group method. Lattice Gauge Theories (LGT), in their
Hamiltonian version, offer a challenging scenario for these techniques. While
the dimensions and sizes of the systems amenable to TNS studies are still far
from those achievable by 4-dimensional LGT tools, Tensor Networks can be
readily used for problems which more standard techniques, such as Markov chain
Monte Carlo simulations, cannot easily tackle. Examples of such problems are
the presence of a chemical potential or out-of-equilibrium dynamics. We have
explored the performance of Matrix Product States in the case of the Schwinger
model, as a widely used testbench for lattice techniques. Using finite-size,
open boundary MPS, we are able to determine the low energy states of the model
in a fully non-perturbative manner and to accurately extract the mass spectrum.
In this work we extend the analysis to the determination of the chiral
condensate, both for massless and massive fermions. The method allows for
accurate finite size and continuum limit extrapolations and produces remarkably
precise results, thus showing the feasibility of these techniques for gauge
theory problems.


title: 7Li NMR Studies of LiCrO2

abstract:
  We report on 7Li NMR studies of a spin S = 3/2 triangular lattice
antiferromagnet LiCrO2 (Neel temperature TN = 62 K) in the paramagnetic state
by using the free-induction decay of 7Li nuclear magnetization. We observed
critical divergence of the 7Li nuclear spin-lattice relaxation rate 1/T1 near
TN, a narrow critical region, and a critical exponent w = 0.45 from a fit of
1/T1 $\propto$ (T/TN - 1)$^{-w}$. Although spin frustration effects have been
explored for this system, the dynamical critical phenomena suggest that LiCrO2
in the critical region is a poor low dimensional antiferromagnetic system.


title: Noise-resilient quantum evolution steered by dynamical decoupling

abstract:
  Realistic quantum computing is subjected to noise. A most important frontier
in research of quantum computing is to implement noise-resilient quantum
control over qubits. Dynamical decoupling can protect coherence of qubits. Here
we demonstrate non-trivial quantum evolution steered by dynamical decoupling
control, which automatically suppresses the noise effect. We designed and
implemented a self-protected controlled-NOT gate on the electron spin of a
nitrogen-vacancy centre and a nearby carbon-13 nuclear spin in diamond at room
temperature, by employing an engineered dynamical decoupling control on the
electron spin. Final state fidelities of 0.91 and 0.88 were observed even with
imperfect initial states. In the mean time, the qubit coherence time has been
elongated by at least 30 folds. The design scheme does not require that the
dynamical decoupling control commute with the qubit interaction and works for
general systems. This work marks a step toward realistic quantum computing.


title:
Perturbative Quantum Field Theory in the Framework of the Fermionic
  Projector

abstract:
  We give a microscopic derivation of perturbative quantum field theory, taking
causal fermion systems and the framework of the fermionic projector as the
starting point. The resulting quantum field theory agrees with standard quantum
field theory on the tree level and reproduces all bosonic loop diagrams. The
fermion loops are described in a different formalism in which no ultraviolet
divergences occur.


title: Dynamical Supergravity Breaking via the Super-Higgs Effect Revisited

abstract:
  We investigate the dynamical breaking of local supersymmetry (supergravity),
including the Deser-Zumino super-Higgs effect, via the corresponding one-loop
effective potential for the simple but quite representative cases of N=1, D=4
simple supergravity and a (simplified) conformal version of it. We find
solutions to the effective equations which indicate dynamical generation of a
gravitino mass, thus breaking supergravity. In the case of conformal
supergravity models, the gravitino mass can be much lower than the Planck
scale, for global supersymmetry breaking scales below the Grand Unification
scale. The absence of instabilities in the effective potential arising from the
quantum fluctuations of the metric field is emphasised, contrary to previous
claims in the literature.


title: Algebraic and Hermitian K-theory of K-rings

abstract:
  The main purpose of the present article is to establish the real case of
"Karoubi's conjecture" in algebraic K-theory. The complex case was proved in
1990-91 by the second author and Andrei Suslin. Compared to the case of complex
algebras, the real case poses additional difficulties. This is due to the fact
that topological K-theory of real Banach algebras has period 8 instead of 2.
The method we employ to overcome these difficulties can be used for complex
algebras, and provides some simplifications to the original proofs. We also
establish a natural analog of "Karoubi's conjecture" in Hermitian K-theory.


title: Fermion Masses Through Condensation in Spacetimes with Torsion

abstract:
  In this paper we argue the possibility that fermion masses, in particular
quarks, originate through the condensation of a fourth family that interacts
with all of the quarks via a contact four-fermion term coming from the
existence of torsion on the spacetime. Extra dimensions are considered to avoid
the hierarchy problem.


title: Generalised probabilistic theories and conic extensions of polytopes

abstract:
  Generalized probabilistic theories (GPT) provide a general framework that
includes classical and quantum theories. It is described by a cone $C$ and its
dual $C^*$. We show that whether some one-way communication complexity problems
can be solved within a GPT is equivalent to the recently introduced cone
factorisation of the corresponding communication matrix $M$. We also prove an
analogue of Holevo's theorem: when the cone $C$ is contained in
$\mathbb{R}^{n}$, the classical capacity of the channel realised by sending GPT
states and measuring them is bounded by $\log n$.
  Polytopes and optimising functions over polytopes arise in many areas of
discrete mathematics. A conic extension of a polytope is the intersection of a
cone $C$ with an affine subspace whose projection onto the original space
yields the desired polytope. Extensions of polytopes can sometimes be much
simpler geometric objects than the polytope itself. The existence of a conic
extension of a polytope is equivalent to that of a cone factorisation of the
slack matrix of the polytope, on the same cone.
  We show that all $0/1$ polytopes whose vertices can be recognized by a
polynomial size circuit, which includes as a special case the travelling
salesman polytope and many other polytopes from combinatorial optimisation,
have small conic extension complexity when the cone is the completely positive
cone.
  Using recent exponential lower bounds on the linear extension complexity of
polytopes, this provides an exponential gap between the communication
complexity of GPT based on the completely positive cone and classical
communication complexity, and a conjectured exponential gap with quantum
communication complexity.
  Our work thus relates the communication complexity of generalisations of
quantum theory to questions of mainstream interest in the area of combinatorial
optimisation.


title: Metric Mean Dimension for Algebraic Actions of Sofic Groups

abstract:
  Recently Bingbing Liang and Hanfeng Li computed the mean dimension and metric
mean dimension for algebraic actions of amenable groups. We show how to extend
their computation of metric mean dimension to the case of sofic groups,
provided that the dual module is finitely generated. Additionally, we show that
when the dual module is finitely presented that the mean dimension is the von
Neumann rank. The proof also goes through introducing \ell^{p}-analogues of
metric mean dimension, which may be seen as an obstruction to the equality of
mean dimension and metric mean dimension.


title: Quantum Algorithms for Finding Constant-sized Sub-hypergraphs

abstract:
  We develop a general framework to construct quantum algorithms that detect if
a $3$-uniform hypergraph given as input contains a sub-hypergraph isomorphic to
a prespecified constant-sized hypergraph. This framework is based on the
concept of nested quantum walks recently proposed by Jeffery, Kothari and
Magniez [SODA'13], and extends the methodology designed by Lee, Magniez and
Santha [SODA'13] for similar problems over graphs. As applications, we obtain a
quantum algorithm for finding a $4$-clique in a $3$-uniform hypergraph on $n$
vertices with query complexity $O(n^{1.883})$, and a quantum algorithm for
determining if a ternary operator over a set of size $n$ is associative with
query complexity $O(n^{2.113})$.


title:
A Polyhedral Method to Compute All Affine Solution Sets of Sparse
  Polynomial Systems

abstract:
  To compute solutions of sparse polynomial systems efficiently we have to
exploit the structure of their Newton polytopes. While the application of
polyhedral methods naturally excludes solutions with zero components, an
irreducible decomposition of a variety is typically understood in affine space,
including also those components with zero coordinates. We present a polyhedral
method to compute all affine solution sets of a polynomial system. The method
enumerates all factors contributing to a generalized permanent. Toric solution
sets are recovered as a special case of this enumeration. For sparse systems as
adjacent 2-by-2 minors our methods scale much better than the techniques from
numerical algebraic geometry.


title: Geometric friction directs cell migration

abstract:
  In the absence of environmental cues, a migrating cell performs an isotropic
random motion. Recently, the breaking of this isotropy has been observed when
cells move in the presence of asymmetric adhesive patterns. However, up to now
the mechanisms at work to direct cell migration in such environments remain
unknown. Here, we show that a non-adhesive surface with asymmetric
micro-geometry consisting of dense arrays of tilted micro-pillars can direct
cell motion. Our analysis reveals that most features of cell trajectories,
including the bias, can be reproduced by a simple model of active Brownian
particle in a ratchet potential, which we suggest originates from a generic
elastic interaction of the cell body with the environment. The observed guiding
effect, independent of adhesion, is therefore robust and could be used to
direct cell migration both in vitro and in vivo.


title:
Bistability in Microcavities with Incoherent Optical or Electrical
  Excitation

abstract:
  We consider a quantum well embedded in a zero-dimensional microcavity with a
sub-wavelength grated mirror, where the x-linearly polarized exciton mode is
strongly coupled to the cavity photon, while y-polarized excitons remain in the
weak coupling regime. Under incoherent optical or electric pumping, we
demonstrate polariton bistability associated with parametric scattering
processes. Such bistability is useful for constructing polaritonic devices with
optical or electrical incoherent pumping.


title: Arithmetic properties of Ap\'ery-like numbers

abstract:
  We provide lower bounds for p-adic valuations of multisums of factorial
ratios which satisfy an Ap\'ery-like recurrence relation: these include
Ap\'ery, Domb, Franel numbers, the numbers of abelian squares over a finite
alphabet, and constant terms of powers of certain Laurent polynomials. In
particular, we prove Beukers' conjectures on the p-adic valuation of Ap\'ery
numbers. Furthermore, we give an effective criterion for a sequence of
factorial ratios to satisfy the p-Lucas property for almost all primes p.


title: Randomization-based models for experiments: I. A chain of randomizations

abstract:
  We derive randomization-based models for experiments with a chain of
randomizations. The estimation theory for these models leads to formulae for
the estimators of treatment effects, their standard errors, and expected mean
squares in the analysis of variance. We discuss the practicalities in fitting
these models and outline the difficulties that can occur, many of which do not
arise in two-tiered experiments.


title:
Nonlinear Oscillations and Bifurcations in Silicon Photonic
  Microresonators

abstract:
  Silicon microdisks are optical resonators that can exhibit surprising
nonlinear behavior. We present a new analysis of the dynamics of these
resonators, elucidating the mathematical origin of spontaneous oscillations and
deriving predictions for observed phenomena such as a frequency comb spectrum
with MHz-scale repetition rate. We test predictions through laboratory
experiment and numerical simulation.

categories: nlin.AO math-ph math.DS math.MP physics.optics


title: Downsampling of optical frequency combs

abstract:
  We demonstrate repetition-rate downsampling of optical frequency combs by way
of pulse gating. The reduced repetition rate enables increased pulse energy,
facilitating efficient spectral broadening and f-2f interferometry. To explore
the technique, we downsample a 250 MHz repetition-rate comb to 25 MHz and
detect the carrier-envelope offset frequency of the downsampled pulse train. We
investigate the effects of pulse gating on the noise properties of the pulse
train and the limitations of the technique by characterizing the phase-noise
spectrum of the downsampled comb and deliberately imposing timing jitter on the
pulse gate. We show that, up to an expected reduction modulo the new repetition
rate, downsampling neither shifts nor introduces noise to the carrier-envelope
offset frequency of the comb above the level of several microhertz.
Additionally, we discuss the effect of downsampling on the spectrum of
intensity fluctuations of the optical pulse train. Finally, we discuss some
practical considerations relevant for the application of the technique to
frequency combs with repetition rates in the 10 GHz range and higher.


title: On the Dual Structure of Thermodynamics

abstract:
  Based on the properties of exponential distribution families we analyze the
Fisher information of the Gibbs canonical ensemble to construct a new state
function for simple systems with no mechanical work. Such a function possesses
nice symmetry properties with respect to Legendre transform and provides a
connection with previous alternative formulations of thermodynamics, most
notably the work by Biot, Serrin and Frieden and collaborators. Logical
extensions to systems with mechanical work may similarly consider generalized
Gibbs ensembles.


title:
Scalable Locality-Sensitive Hashing for Similarity Search in
  High-Dimensional, Large-Scale Multimedia Datasets

abstract:
  Similarity search is critical for many database applications, including the
increasingly popular online services for Content-Based Multimedia Retrieval
(CBMR). These services, which include image search engines, must handle an
overwhelming volume of data, while keeping low response times. Thus,
scalability is imperative for similarity search in Web-scale applications, but
most existing methods are sequential and target shared-memory machines. Here we
address these issues with a distributed, efficient, and scalable index based on
Locality-Sensitive Hashing (LSH). LSH is one of the most efficient and popular
techniques for similarity search, but its poor referential locality properties
has made its implementation a challenging problem. Our solution is based on a
widely asynchronous dataflow parallelization with a number of optimizations
that include a hierarchical parallelization to decouple indexing and data
storage, locality-aware data partition strategies to reduce message passing,
and multi-probing to limit memory usage. The proposed parallelization attained
an efficiency of 90% in a distributed system with about 800 CPU cores. In
particular, the original locality-aware data partition reduced the number of
messages exchanged in 30%. Our parallel LSH was evaluated using the largest
public dataset for similarity search (to the best of our knowledge) with $10^9$
128-d SIFT descriptors extracted from Web images. This is two orders of
magnitude larger than datasets that previous LSH parallelizations could handle.


title:
Asteroseismological study of massive ZZ Ceti stars with fully
  evolutionary models

abstract:
  We present the first asteroseismological study for 42 massive ZZ Ceti stars
based on a large set of fully evolutionary carbon$-$oxygen core DA white dwarf
models characterized by a detailed and consistent chemical inner profile for
the core and the envelope. Our sample comprise all the ZZ Ceti stars with
spectroscopic stellar masses between 0.72 and $1.05M_{\odot}$ known to date.
The asteroseismological analysis of a set of 42 stars gives the possibility to
study the ensemble properties of the massive pulsating white dwarf stars with
carbon$-$oxygen cores, in particular the thickness of the hydrogen envelope and
the stellar mass. A significant fraction of stars in our sample have stellar
mass high enough as to crystallize at the effective temperatures of the ZZ Ceti
instability strip, which enables us to study the effects of crystallization on
the pulsation properties of these stars. Our results show that the phase
diagram presented in Horowitz et al. (2010) seems to be a good representation
of the crystallization process inside white dwarf stars, in agreement with the
results from white dwarf luminosity function in globular clusters.


title:
The phase transition in the anisotropic Heisenberg model with long range
  dipolar interactions

abstract:
  In this work we have used extensive Monte Carlo calculations to study the
planar to paramagnetic phase transition in the two-dimensional anisotropic
Heisenberg model with dipolar interactions (AHd) considering the true
long-range character of the dipolar interactions by means of the Ewald
summation. Our results are consistent with an order-disorder phase transition
with unusual critical exponents in agreement with our previous results for the
Planar Rotator model with dipolar interactions. Nevertheless, our results
disagrees with the Renormalization Group results of Maier and Schwabl [PRB, 70,
134430 (2004)] and the results of Rapini et. al. [PRB, 75, 014425 (2007)],
where the AHd was studied using a cut-off in the evaluation of the dipolar
interactions. We argue that besides the long-range character of dipolar
interactions their anisotropic character may have a deeper effect in the system
than previously believed. Besides, our results shows that the use of a cut-off
radius in the evaluation of dipolar interactions must be avoided when analyzing
the critical behavior of magnetic systems, since it may lead to erroneous
results.


title: Entropic forces in Brownian motion

abstract:
  The interest in the concept of entropic forces has risen considerably since
E. Verlinde proposed to interpret the force in Newton s second law and Gravity
as entropic forces [1]. Brownian motion, the motion of a small particle
(pollen) driven by random impulses from the surrounding molecules, may be the
first example of a stochastic process in which such forces are expected to
emerge. In this note it is shown that at least two types of entropic force can
be identified in the case of 3D Brownian motion (or random walk). This yields
simple derivations of known results of Brownian motion, Hook s law and,
applying an external (non-radial) force, Curie s law and the Langevin-Debye
equation.


title: Information-theoretical formulation of anyonic entanglement

abstract:
  Anyonic systems are modeled by topologically protected Hilbert spaces which
obey complex superselection rules restricting possible operations. These
Hilbert spaces cannot be decomposed into tensor products of spatially localized
subsystems, whereas the tensor product structure is a foundation of the
standard entanglement theory. We formulate bipartite entanglement theory for
pure anyonic states and analyze its properties as a non-local resource for
quantum information processing. We introduce a new entanglement measure,
asymptotic entanglement entropy (AEE), and show that it characterizes
distillable entanglement and entanglement cost similarly to entanglement
entropy in conventional systems. AEE depends not only on the Schmidt
coefficients but also on the quantum dimensions of the anyons shared by the
local subsystems. Moreover, it turns out that AEE coincides with the
entanglement gain by anyonic excitations in certain topologically ordered
phases.


title: Topological Additive Numbering of Directed Acyclic Graphs

abstract:
  We propose to study a problem that arises naturally from both Topological
Numbering of Directed Acyclic Graphs, and Additive Coloring (also known as
Lucky Labeling). Let $D$ be a digraph and $f$ a labeling of its vertices with
positive integers; denote by $S(v)$ the sum of labels over all neighbors of
each vertex $v$. The labeling $f$ is called \emph{topological additive
numbering} if $S(u) < S(v)$ for each arc $(u,v)$ of the digraph. The problem
asks to find the minimum number $k$ for which $D$ has a topological additive
numbering with labels belonging to $\{ 1, \ldots, k \}$, denoted by
$\eta_t(D)$.
  We characterize when a digraph has topological additive numberings, give a
lower bound for $\eta_t(D)$, and provide an integer programming formulation for
our problem, characterizing when its coefficient matrix is totally unimodular.
We also present some families for which $\eta_t(D)$ can be computed in
polynomial time. Finally, we prove that this problem is \np-Hard even when its
input is restricted to planar bipartite digraphs.


title: Quantum harmonic oscillator in option pricing

abstract:
  The Black-Scholes model anticipates rather well the observed prices for
options in the case of a strike price that is not too far from the current
price of the underlying asset. Some useful extensions can be obtained by an
adequate modification of the coefficients in the Black-Scholes equation. We
investigate from a mathematical point of view an extension directly related to
the quantum harmonic oscillator. In the considered case, the solution is the
sum of a series involving the Hermite-Gauss functions. A finite-dimensional
version is obtained by using a finite oscillator and the Harper functions. This
simplified model keeps the essential characteristics of the continuous one and
uses finite sums instead of series and integrals.


title:
Dynamical Emergence of Universal Horizons during the formation of Black
  Holes

abstract:
  Motivations for the existence of a fundamental preferred frame range from
pure phenomenology to attempts to solve the non-renormalizability of quantum
gravity, the problem of time (and scale), and the cosmological constant
problem(s). In many explicit constructions, such as Einstein-Aether or
Gravitational Aether theories, K-essence, Cuscuton theory, Shape Dynamics, or
(non-projectable) Horava-Lifshitz gravity, the low energy theory contains a
fluid (which defines a preferred frame) with superluminal or incompressible
excitations. We study here the formation of black holes in the presence of such
a fluid. In particular, we focus on the incompressible limit of the fluid (or
Constant Mean Curvature foliation) in the space-time of a spherically
collapsing shell within an asymptotically cosmological space-time. In this
case, ignoring the fluid back reaction, we can analytically show that an
observer inside 3/4 of the Schwarzschild radius cannot send a signal outside,
after a stage in collapse, even using signals that propagate infinitely fast in
the preferred frame. This confirms the dynamical emergence of universal
horizons that have been previously found in static solutions. We argue that
this universal horizon should be considered as the future boundary of the
classical space-time.


title:
Drude weight, Meissner weight, rotational inertia of bosonic
  superfluids: how are they distinguished?

abstract:
  The Drude weight, the quantity which distinguishes metals from insulators, is
proportional to the second derivative of the ground state energy with respect
to a flux at zero flux. The same expression also appears in the definition of
the Meissner weight, the quantity which indicates superconductivity, as well as
in the definition of non-classical rotational inertia of bosonic superfluids.
It is shown that the difference between these quantities depends on the
interpretation of the average momentum term, which can be understood as the
expectation value of the total momentum (Drude weight), the sum of the
expectation values of single momenta (rotational inertia of a superfluid), or
the sum over expectation values of momentum pairs (Meissner weight). This
distinction appears naturally when the current from which the particular
transport quantity is derived is cast in terms of shift operators.


title:
The WKB approximation of semiclassical eigenvalues of the
  Zakharov-Shabat problem

abstract:
  We numerically compute eigenvalues of the non-self-adjoint Zakharov--Shabat
problem in the semiclassical regime. In particular, we compute the eigenvalues
for a Gaussian potential and compare the results to the corresponding (formal)
WKB approximations used in the approach to the semiclassical or zero-dispersion
limit of the focusing nonlinear Schroedinger equation via semiclassical soliton
ensembles. This numerical experiment, taken together with recent numerical
experiments [17,18], speaks directly to the viability of this approach; in
particular, our experiment suggests a value for the rate of convergence of the
WKB eigenvalues to the true eigenvalues in the semiclassical limit. This
information provides some hint as to how these approximations might be
rigorously incorporated into the asymptotic analysis of the singular limit for
the associated nonlinear partial differential equation.


title:
Measurements of properties of the Higgs-like Particle at 125 GeV by the
  CMS collaboration

abstract:
  CMS results on the measurement of properties of the Higgs-like particle
discovered last summer with a mass near 126 GeV are presented. The results are
based on a data samples corresponding to an integrated luminosity of up to 5.1
fb-1 at 7 TeV and up to 19.6 fb-1 at 8 TeV in proton-proton collisions at the
LHC. Five decay modes are studied: gamma-gamma, ZZ, WW, tau-tau and bb. The
event yields obtained by different analyses targeting specific decay modes and
production mechanisms are consistent with those expected for the Standard Model
(SM) Higgs boson. The mass of the new boson is measured to be 125.7 +- 0.4 GeV.
The best-fit signal strength for all channels combined, expressed in units of
the SM Higgs boson cross section, is 0.80 +- 0.14 at the measured mass. A
discussion on the consistency of the couplings and the spin-parity properties
of the observed boson with those predicted for the SM Higgs boson is presented,
updated with the most recent results. No significant deviations are found.


title: The suppression of star formation by powerful active galactic nuclei

abstract:
  The old, red stars which constitute the bulges of galaxies, and the massive
black holes at their centres, are the relics of a period in cosmic history when
galaxies formed stars at remarkable rates and active galactic nuclei (AGN)
shone brightly from accretion onto black holes. It is widely suspected, but
unproven, that the tight correlation in mass of the black hole and stellar
components results from the AGN quenching the surrounding star formation as it
approaches its peak luminosity. X-rays trace emission from AGN unambiguously,
while powerful star-forming galaxies are usually dust-obscured and are
brightest at infrared to submillimetre wavelengths. Here we report observations
in the submillimetre and X-ray which show that rapid star formation was common
in the host galaxies of AGN when the Universe was 2-6 Gyrs old, but that the
most vigorous star formation is not observed around black holes above an X-ray
luminosity of 10^44 erg/s. This suppression of star formation in the host
galaxies of powerful AGN is a key prediction of models in which the AGN drives
a powerful outflow, expelling the interstellar medium of its host galaxy and
transforming the galaxy's properties in a brief period of cosmic time.


title: Silicon Atomic Quantum Dots Enable Beyond-CMOS Electronics

abstract:
  We review our recent efforts in building atom-scale quantum-dot cellular
automata circuits on a silicon surface. Our building block consists of silicon
dangling bond on a H-Si(001) surface, which has been shown to act as a quantum
dot. First the fabrication, experimental imaging, and charging character of the
dangling bond are discussed. We then show how precise assemblies of such dots
can be created to form artificial molecules. Such complex structures can be
used as systems with custom optical properties, circuit elements for
quantum-dot cellular automata, and quantum computing. Considerations on
macro-to-atom connections are discussed.


title:
Achievable Rates for Four-Dimensional Coded Modulation with a Bit-Wise
  Receiver

abstract:
  We study achievable rates for four-dimensional (4D) constellations for
spectrally efficient optical systems based on a (suboptimal) bit-wise receiver.
We show that PM-QPSK outperforms the best 4D constellation designed for uncoded
transmission by approximately 1 dB. Numerical results using LDPC codes validate
the analysis.


title: Asymptotically Optimal Topological Quantum Compiling

abstract:
  In a topological quantum computer, universality is achieved by braiding and
quantum information is natively protected from small local errors. We address
the problem of compiling single-qubit quantum operations into braid
representations for non-abelian quasiparticles described by the Fibonacci anyon
model. We develop a probabilistically polynomial algorithm that outputs a braid
pattern to approximate a given single-qubit unitary to a desired precision. We
also classify the single-qubit unitaries that can be implemented exactly by a
Fibonacci anyon braid pattern and present an efficient algorithm to produce
their braid patterns. Our techniques produce braid patterns that meet the
uniform asymptotic lower bound on the compiled circuit depth and thus are
depth-optimal asymptotically. Our compiled circuits are significantly shorter
than those output by prior state-of-the-art methods, resulting in improvements
in depth by factors ranging from 20 to 1000 for precisions ranging between
$10^{-10}$ and $10^{-30}$.


title:
Green's functions from real-time bold-line Monte Carlo: spectral
  properties of the nonequilibrium Anderson impurity model

abstract:
  The nonequilibrium spectral properties of the Anderson impurity model with a
chemical potential bias are investigated within a numerically exact real time
quantum Monte Carlo formalism. The two-time correlation function is computed in
a form suitable for nonequilibrium dynamical mean field calculations.
Additionally, the evolution of the model's spectral properties are simulated in
an alternative representation, defined by a hypothetical but experimentally
realizable weakly coupled auxiliary lead. The voltage splitting of the Kondo
peak is confirmed and the dynamics of its formation after a coupling or gate
quench are studied. This representation is shown to contain additional
information about the dot's population dynamics. Further, we show that the
voltage-dependent differential conductance gives a reasonable qualitative
estimate of the equilibrium spectral function, but significant qualitative
differences are found including incorrect trends and spurious temperature
dependent effects.


title:
Optical lattices with large scattering length: Using few-body physics to
  simulate an electron-phonon system

abstract:
  We propose to go beyond the usual Hubbard model description of atoms in
optical lattices and show how few-body physics can be used to simulate
many-body phenomena, e.g., an electron-phonon system. We take one atomic
species to be trapped in a deep optical lattice at full filling and another to
be untrapped spin-polarized fermions (which do not see the optical lattice) but
has an s-wave contact interaction with the first species. For large positive
scattering length on the order of lattice spacing, the usual two-body bound
(dimer) states overlap forming giant orbitals extending over the entire
lattice, which can be viewed as an "electronic" band for the untrapped species
while the trapped atoms become the "ions" with their own on-site dynamics,
thereby simulating an electron-phonon system with renormalization of the phonon
frequencies and Peierls transitions. This setup requires large scattering
lengths but minimises losses, does not need higher bands and adds new degrees
of freedom which cannot easily be described in terms of lattice variables, thus
opening up intriguing possibilities to explore interesting physics at the
interface between few-body and many-body systems.


title: Hamiltonian quantum simulation with bounded-strength controls

abstract:
  We propose dynamical control schemes for Hamiltonian simulation in many-body
quantum systems that avoid instantaneous control operations and rely solely on
realistic bounded-strength control Hamiltonians. Each simulation protocol
consists of periodic repetitions of a basic control block, constructed as a
suitable modification of an "Eulerian decoupling cycle," that would otherwise
implement a trivial (zero) target Hamiltonian. For an open quantum system
coupled to an uncontrollable environment, our approach may be employed to
engineer an effective evolution that simulates a target Hamiltonian on the
system, while suppressing unwanted decoherence to the leading order. We present
illustrative applications to both closed- and open-system simulation settings,
with emphasis on simulation of non-local (two-body) Hamiltonians using only
local (one-body) controls. In particular, we provide simulation schemes
applicable to Heisenberg-coupled spin chains exposed to general linear
decoherence, and show how to simulate Kitaev's honeycomb lattice Hamiltonian
starting from Ising-coupled qubits, as potentially relevant to the dynamical
generation of a topologically protected quantum memory. Additional implications
for quantum information processing are discussed.


title:
Weak Commutation Relations and Eigenvalue Statistics for Products of
  Rectangular Random Matrices

abstract:
  We study the joint probability density of the eigenvalues of a product of
rectangular real, complex or quaternion random matrices in a unified way. The
random matrices are distributed according to arbitrary probability densities,
whose only restriction is the invariance under left and right multiplication by
orthogonal, unitary or unitary symplectic matrices, respectively. We show that
a product of rectangular matrices is statistically equivalent to a product of
square matrices. Hereby we prove a weak commutation relation of the random
matrices at finite matrix sizes, which previously have been discussed for
infinite matrix size. Moreover we derive the joint probability densities of the
eigenvalues. To illustrate our results we apply them to a product of random
matrices drawn from Ginibre ensembles and Jacobi ensembles as well as a mixed
version thereof. For these weights we show that the product of complex random
matrices yield a determinantal point process, while the real and quaternion
matrix ensembles correspond to Pfaffian point processes. Our results are
visualized by numerical simulations. Furthermore, we present an application to
a transport on a closed, disordered chain coupled to a particle bath.


title:
Variation in the dust emissivity index across M33 with Herschel and
  Spitzer (HerM33es)

abstract:
  We study the wavelength dependence of the dust emission as a function of
position and environment across the disk of M33 at a linear resolution of 160
pc using Spitzer and Herschel photometric data. Expressing the emissivity of
the dust as a power law, the power-law exponent (beta) is estimated from two
independent approaches designed to properly treat the degeneracy between beta
and the dust temperature. Both beta and the dust temperature are higher in the
inner disk than in the outer disk, contrary to reported beta-T
anti-correlations found in other sources. In the cold + warm dust model, the
warm component and the ionized gas (Halpha) have a very similar distribution
across the galaxy, demonstrating that the model separates the components in an
appropriate fashion. The flocculent spiral arms and the dust lanes are evident
in the map of the cold component. Both cold and warm dust column densities are
high in star forming regions and reach their maxima toward the giant star
forming complexes NGC604 and NGC595. beta declines from close to 2 in the
center to about 1.3 in the outer disk. beta is positively correlated with star
formation and with molecular gas column, as traced by Halpha and CO emission.
The lower dust emissivity index in the outer parts of M33 is likely related to
the reduced metallicity (different grain composition) and possibly different
size distribution. It is not due to the decrease in stellar radiation field or
temperature in a simple way because the FIR-bright regions in the outer disk
also have a low beta. Like most spirals, M33 has a (decreasing) radial gradient
in star formation and molecular-to-atomic gas ratio such that the regions
bright in Halpha or CO tend to trace the inner disk, making it difficult to
distinguish between their effects on the dust.


title: Validation Rules for Assessing and Improving SKOS Mapping Quality

abstract:
  The Simple Knowledge Organization System (SKOS) is popular for expressing
controlled vocabularies, such as taxonomies, classifications, etc., for their
use in Semantic Web applications. Using SKOS, concepts can be linked to other
concepts and organized into hierarchies inside a single terminology system.
Meanwhile, expressing mappings between concepts in different terminology
systems is also possible. This paper discusses potential quality issues in
using SKOS to express these terminology mappings. Problematic patterns are
defined and corresponding rules are developed to automatically detect
situations where the mappings either result in 'SKOS Vocabulary Hijacking' to
the source vocabularies or cause conflicts. An example of using the rules to
validate sample mappings between two clinical terminologies is given. The
validation rules, expressed in N3 format, are available as open source.


title:
Stability of 41 metal - boron systems at 0 GPa and 30 GPa from first
  principles

abstract:
  A multitude of observed boron-based materials have outstanding
superconducting, mechanical, and refractory properties. Yet, the structure, the
composition, and the very existence of some reported metal boride (M-B)
compounds have been a subject of extensive debate. This density functional
theory work seeks to set a baseline for current understanding of known metal
boride phases as well as to identify new synthesizable candidates. We have
generated a database of over 12,000 binary M-B entries for pressures of 0 and
30 GPa producing the largest scan of compositions and systems in this materials
class. The 175 selected crystal structures include both observed prototypes and
new ones found with our evolutionary ground state search. The metals considered
are: Al, Ag, Au, Ba, Be, Ca, Cd, Co, Cr, Cs, Cu, Fe, Hf, Hg, Ir, K, La, Li, Mg,
Mn, Mo, Na, Nb, Ni, Os, Pd, Pt, Rb, Re, Rh, Ru, Sc, Sr, Ta, Tc, Ti, V, W, Y,
Zn, and Zr. Based on the formation energy calculated at zero pressure and
temperature 4 new M-B phases or structures have been predicted, while a number
of previously reported compounds have been shown to be unstable. At 30 GPa,
changes in the convex hulls are expected to occur in 18 out of 41 M-B systems,
which is used to indicate regions of the periodic table (for metal borides)
that require further investigation from the community. Analysis of the
collected information has revealed a nearly linear relationship between the
magnetic moment per atom and the metal content for all the Fe-B, Co-B, and Ni-B
structures within 0.15 eV/atom of the stability tie line. Both GGA-PBE and
LDA-PW functionals were used to provide an understanding of the systematic
error introduced by the choice of the exchange-correlation functional.


title:
Hole Concentration Effect on the Microwave Nonlinearity of
  Tl2Ba2CaCu2O8-d Superconducting Thin Films

abstract:
  The carrier concentration of Tl2Ba2CaCu2O8 films was modified by annealing in
N2 gas. X-ray analysis of the structure and the oxygen content revealed a
correspondence between carrier concentration and oxygen depletion. The TC and
nonlinear surface impedance was measured using a dielectric resonator and the
nonlinearity slope parameter r=dXS/dRS was found to converge to unity at the
critical temperature, indicating a dominance of Josephson fluxon hysteresis on
the nonlinearity. Highly inductive nonlinearity was observed in a small range
of doping levels between 0.180<p<0.195 holes/Cu, which does not include the
optimal doping level of 0.16 holes/Cu.


title: Positively oriented matroids are realizable

abstract:
  We prove da Silva's 1987 conjecture that any positively oriented matroid is a
positroid; that is, it can be realized by a set of vectors in a real vector
space. It follows from this result and a result of the third author that the
positive matroid Grassmannian (or positive MacPhersonian) is homeomorphic to a
closed ball.


title:
Degeneracy in sparse ERGMs with functions of degrees as sufficient
  statistics

abstract:
  A sufficient criterion for "non-degeneracy" is given for Exponential Random
Graph Models on sparse graphs with sufficient statistics which are functions of
the degree sequence. This criterion explains why statistics such as alternating
$k$-star are non-degenerate, whereas subgraph counts are degenerate. It is
further shown that this criterion is "almost" tight. Existence of consistent
estimates is then proved for non-degenerate Exponential Random Graph Models.


title:
Remark on the Novikov conjecture and the homotopy invariance of the
  Hirzebruch L-class

abstract:
  We use K-area homology to summarize some results about the Novikov conjecture
and the Hirzebruch L-class. In fact, we provide necessary and sufficient
conditions for closed manifolds to have a homotopy invariant L-class. In order
to obtain additional properties we also introduce the cohomology of infinite
K--area which preserves the cup product of singular cohomology.


title:
Competition vs. Cooperation: A Game-Theoretic Decision Analysis for MIMO
  HetNets

abstract:
  This paper addresses the problem of competition vs. cooperation in the
downlink, between base stations (BSs), of a multiple input multiple output
(MIMO) interference, heterogeneous wireless network (HetNet). This research
presents a scenario where a macrocell base station (MBS) and a cochannel
femtocell base station (FBS) each simultaneously serving their own user
equipment (UE), has to choose to act as individual systems or to cooperate in
coordinated multipoint transmission (CoMP). The paper employes both the
theories of non-cooperative and cooperative games in a unified procedure to
analyze the decision making process. The BSs of the competing system are
assumed to operate at the\emph{}maximum expected sum
rate\emph{}(MESR)\emph{}correlated equilibrium\emph{}(CE), which is compared
against the value of CoMP to establish the stability of the coalition. It is
proven that there exists a threshold geographical separation, $d_{\text{th}}$,
between the macrocell user equipment (MUE) and FBS, under which the region of
coordination is non-empty. Theoretical results are verified through
simulations.


title: A Mirror Theorem for Toric Stacks

abstract:
  We prove a Givental-style mirror theorem for toric Deligne--Mumford stacks X.
This determines the genus-zero Gromov--Witten invariants of X in terms of an
explicit hypergeometric function, called the I-function, that takes values in
the Chen--Ruan orbifold cohomology of X.


title: Phase transition in the two star Exponential Random Graph Model

abstract:
  This paper gives a way to simulate from the two star probability distribution
on the space of simple graphs via auxiliary variables. Using this simulation
scheme, the model is explored for various domains of the parameter values, and
the phase transition boundaries are identified, and shown to be similar as that
of the Curie-Weiss model of statistical physics. Concentration results are
obtained for all the degrees, which further validate the phase transition
predictions.


title:
Global Photometric Properties of Asteroid (4) Vesta Observed with Dawn
  Framing Camera

abstract:
  Dawn spacecraft orbited Vesta for more than one year and collected a huge
volume of multispectral, high-resolution data in the visible wavelengths with
the Framing Camera. We present a detailed disk-integrated and disk-resolved
photometric analysis using the Framing Camera images with the Minnaert model
and the Hapke model, and report our results about the global photometric
properties of Vesta. The photometric properties of Vesta show weak or no
dependence on wavelengths, except for the albedo. At 554 nm, the global average
geometric albedo of Vesta is 0.38+/-0.04, and the Bond albedo range is
0.20+/-0.02. The bolometric Bond albedo is 0.18+/-0.01. The phase function of
Vesta is similar to those of S-type asteroids. Vesta's surface shows a
single-peaked albedo distribution with a full-width-half-max ~17% relative to
the global average. This width is much smaller than the full range of albedos
(from ~0.55x to >2x global average) in localized bright and dark areas of a few
tens of km in sizes, and is probably a consequence of significant regolith
mixing on the global scale. Rheasilvia basin is about 10% brighter than the
global average. The phase reddening of Vesta measured from Dawn Framing Camera
images is comparable or slightly stronger than that of Eros as measured by the
Near Earth Asteroid Rendezvous mission, but weaker than previous measurements
based on ground-based observations of Vesta and laboratory measurements of HED
meteorites. The photometric behaviors of Vesta are best described by the Hapke
model and the Akimov disk- function, when compared with the Minnaert model,
Lommel-Seeliger model, and Lommel- Seeliger-Lambertian model. The traditional
approach for photometric correction is validated for Vesta for >99% of its
surface where reflectance is within +/-30% of global average.


title: Spreading of cooperative behaviour across interdependent groups

abstract:
  Recent empirical research has shown that links between groups reinforce
individuals within groups to adopt cooperative behaviour. Moreover, links
between networks may induce cascading failures, competitive percolation, or
contribute to efficient transportation. Here we show that there in fact exists
an intermediate fraction of links between groups that is optimal for the
evolution of cooperation in the prisoner's dilemma game. We consider individual
groups with regular, random, and scale-free topology, and study their different
combinations to reveal that an intermediate interdependence optimally
facilitates the spreading of cooperative behaviour between groups. Excessive
between-group links simply unify the two groups and make them act as one, while
too rare between-group links preclude a useful information flow between the two
groups. Interestingly, we find that between-group links are more likely to
connect two cooperators than in-group links, thus supporting the conclusion
that they are of paramount importance.


title: Optimal finite-time erasure of a classical bit

abstract:
  Information erasure inevitably leads to heat dissipation. Minimizing this
dissipation will be crucial for developing small-scale information processing
systems, but little is known about the optimal procedures required. We have
obtained closed-form expressions for maximally efficient erasure cycles for
deletion of a classical bit of information stored by the position of a particle
diffusing in a double-well potential. We find that the extra dissipation beyond
the Landauer bound is proportional to the square of the Hellinger distance
between the initial and final states divided by the cycle duration, which
quantifies how far out of equilibrium the system is driven. Finally, we
demonstrate close agreement between the exact optimal cycle and the protocol
found using a linear response framework.


title:
A Mobile Robotic Personal Nightstand with Integrated Perceptual
  Processes

abstract:
  We present an intelligent interactive nightstand mounted on a mobile robot,
to aid the elderly in their homes using physical, tactile and visual percepts.
We show the integration of three different sensing modalities for controlling
the navigation of a robot mounted nightstand within the constrained environment
of a general purpose living room housing a single aging individual in need of
assistance and monitoring. A camera mounted on the ceiling of the room, gives a
top-down view of the obstacles, the person and the nightstand. Pressure sensors
mounted beneath the bed-stand of the individual provide physical perception of
the person's state. A proximity IR sensor on the nightstand acts as a tactile
interface along with a Wii Nunchuck (Nintendo) to control mundane operations on
the nightstand. Intelligence from these three modalities are combined to enable
path planning for the nightstand to approach the individual. With growing
emphasis on assistive technology for the aging individuals who are increasingly
electing to stay in their homes, we show how ubiquitous intelligence can be
brought inside homes to help monitor and provide care to an individual. Our
approach goes one step towards achieving pervasive intelligence by seamlessly
integrating different sensors embedded in the fabric of the environment.


title: Naming Game on Networks: Let Everyone be Both Speaker and Hearer

abstract:
  To investigate how consensus is reached on a large self-organized
peer-to-peer network, we extended the naming game model commonly used in
language and communication to Naming Game in Groups (NGG). Differing from other
existing naming game models, in NGG, everyone in the population (network) can
be both speaker and hearer simultaneously, which resembles in a closer manner
to real-life scenarios. Moreover, NGG allows the transmission (communication)
of multiple words (opinions) for multiple intra-group consensuses. The
communications among indirectly-connected nodes are also enabled in NGG. We
simulated and analyzed the consensus process in some typical network
topologies, including random-graph networks, small-world networks and
scale-free networks, to better understand how global convergence (consensus)
could be reached on one common word. The results are interpreted on group
negotiation of a peer-to-peer network, which shows that global consensus in the
population can be reached more rapidly when more opinions are permitted within
each group or when the negotiating groups in the population are larger in size.
The novel features and properties introduced by our model have demonstrated its
applicability in better investigating general consensus problems on
peer-to-peer networks.


title: Perseus I: A distant satellite dwarf galaxy of Andromeda

abstract:
  We present the discovery of a new dwarf galaxy, Perseus I/Andromeda XXXIII,
found in the vicinity of Andromeda (M31) in stacked imaging data from the
Pan-STARRS1 3{\pi} survey. Located 27.9{\deg} away from M31, Perseus I has a
heliocentric distance of 785 +/- 65 kpc, compatible with it being a satellite
of M31 at 374 +14/-10 kpc from its host. The properties of Perseus I are
typical for a reasonably bright dwarf galaxy (M_V = -10.3 +/- 0.7), with an
exponential half-light radius of r_h = 1.7 +/- 0.4 arcminutes or r_h = 400
+105/-85 pc at this distance, and a moderate ellipticity (\epsilon = 0.43
+0.15/-0.17). The late discovery of Perseus I is due to its fairly low surface
brightness (\mu_0=25.7 +1.0/-0.9 mag/arcsec^2), and to the previous lack of
deep, high quality photometric data in this region. If confirmed to be a
companion of M31, the location of Perseus I, far east from its host, could
place interesting constraints on the bulk motion of the satellite system of
M31.


title: Fundamental Vibrational Transitions of HCl Detected in CRL 2136

abstract:
  We would like to understand the chemistry of dense clouds and their hot cores
more quantitatively by obtaining more complete knowledge of the chemical
species present in them. We have obtained high-resolution infrared absorption
spectroscopy at 3-4 um toward the bright infrared source CRL 2136. The
fundamental vibration-rotation band of HCl has been detected within a dense
cloud for the first time. The HCl is probably located in the warm compact
circumstellar envelope or disk of CRL 2136. The fractional abundance of HCl is
(4.9-8.7)e-8, indicating that approximately 20 % of the elemental chlorine is
in gaseous HCl. The kinetic temperature of the absorbing gas is 250 K, half the
value determined from infrared spectroscopy of 13CO and water. The percentage
of chlorine in HCl is approximately that expected for gas at this temperature.
The reason for the difference in temperatures between the various molecular
species is unknown.


title:
The Gemini NICI Planet-Finding Campaign: The Companion Detection
  Pipeline

abstract:
  We present the high-contrast image processing techniques used by the Gemini
NICI Planet-Finding Campaign to detect faint companions to bright stars. NICI
(Near Infrared Coronagraphic Imager) is an adaptive optics instrument installed
on the 8-m Gemini South telescope, capable of angular and spectral difference
imaging and specifically designed to image exoplanets. The Campaign data
pipeline achieves median contrasts of 12.6 magnitudes at 0.5" and 14.4
magnitudes at 1" separation, for a sample of 45 stars (V= 4.3-13.9 mag) from
the early phase of the Campaign. We also present a novel approach to
calculating contrast curves for companion detection based on 95% completeness
in the recovery of artificial companions injected into the raw data, while
accounting for the false-positive rate. We use this technique to select the
image processing algorithms that are more successful at recovering faint
simulated point sources. We compare our pipeline to the performance of the LOCI
algorithm for NICI data and do not find significant improvement with LOCI.


title: Ising nematic fluid phase of hard-core dimers on the square lattice

abstract:
  We present a model of classical hard-core dimers on the square lattice that
contains an Ising nematic phase in its phase diagram. We consider a model with
an attractive interaction for parallel dimers on a given plaquette of the
square lattice and an attractive interaction for neighboring parallel dimers on
the same row ({\it viz} column) of the lattice. By extensive Monte carlo
simulations we find that with a finite density of holes the phase diagram has,
with rising temperatures, a columnar crystalline phase, an Ising nematic liquid
phase and a disordered fluid phase, separated by Ising continuous phase
transitions. We present strong evidence for the Ising universality class of
both transitions. The Ising nematic phase can be interpreted as either an
intermediate classical thermodynamic phase (possibly of a strongly correlated
antiferromagnet) or as a phase of a 2D quantum dimer model using the
Rokhsar-Kivelson construction of exactly solvable quantum Hamiltonians.

categories: cond-mat.str-el cond-mat.mtrl-sci cond-mat.soft cond-mat.stat-mech cond-mat.supr-con