title: $AdS_3/CFT_2$, finite-gap equations and massless modes

abstract:
  It is known that string theory on $AdS_3\times M_7$ backgrounds preserving 16
supercharges is classically integrable. This integrability has been previously
used to write down a set of integral equations, known as the finite-gap
equations. These equations can be solved for the closed string spectrum of the
theory. However, it has been known for some time that the $AdS_3\times M_7$
finite-gap equations do not capture the dynamics of the massless modes of the
closed string theory. In this paper we re-examine the derivation of the
$AdS_3\times M_7$ finite-gap system. We find that the conditions that had
previously been imposed on these integral equations in order to implement the
Virasoro constraints are too strict, and are in fact not required. We identify
the correct implementation of the Virasoro constraints on finite-gap equations
and show that this new, less restrictive condition captures the complete closed
string spectrum on $AdS_3\times M_7$.


title:
Power Scheduling of Kalman Filtering in Wireless Sensor Networks with
  Data Packet Drops

abstract:
  For a wireless sensor network (WSN) with a large number of low-cost,
battery-driven, multiple transmission power leveled sensor nodes of limited
transmission bandwidth, then conservation of transmission resources (power and
bandwidth) is of paramount importance. Towards this end, this paper considers
the problem of power scheduling of Kalman filtering for general linear
stochastic systems subject to data packet drops (over a packet-dropping
wireless network). The transmission of the acquired measurement from the sensor
to the remote estimator is realized by sequentially transmitting every single
component of the measurement to the remote estimator in one time period. The
sensor node decides separately whether to use a high or low transmission power
to communicate every component to the estimator across a packet-dropping
wireless network based on the rule that promotes the power scheduling with the
least impact on the estimator mean squared error. Under the customary
assumption that the predicted density is (approximately) Gaussian, leveraging
the statistical distribution of sensor data, the mechanism of power scheduling,
the wireless network effect and the received data, the minimum mean squared
error estimator is derived. By investigating the statistical convergence
properties of the estimation error covariance, we establish, for general linear
systems, both the sufficient condition and the necessary condition guaranteeing
the stability of the estimator.


title:
Misfortunes of a mathematicians' trio using Computer Algebra Systems:
  Can we trust?

abstract:
  Computer algebra systems are a great help for mathematical research but
sometimes unexpected errors in the software can also badly affect it. As an
example, we show how we have detected an error of Mathematica computing
determinants of matrices of integer numbers: not only it computes the
determinants wrongly, but also it produces different results if one evaluates
the same determinant twice.


title:
Angular Momentum Exchange Between Light and Material Media Deduced from
  the Doppler Shift

abstract:
  Electromagnetic waves carry energy as well as linear and angular momenta.
When a light pulse is reflected from, transmitted through, or absorbed by a
material medium, energy and momentum (both linear and angular) are generally
exchanged, while the total amount of each entity remains intact. The extent of
such exchanges between light and matter can be deduced, among other methods,
with the aid of the Doppler shift phenomenon. The main focus of the present
paper is on the transfer of angular momentum from a monochromatic light pulse
to spinning objects such as a mirror, an absorptive dielectric, or a
birefringent plate. The fact that individual photons of frequency omega carry
energy in the amount of h_bar*omega, where h_bar is Planck's reduced constant,
enables one to relate the Doppler shift to the amount of energy exchanged.
Under certain circumstances, the knowledge of exchanged energy leads directly
to a determination of the momentum transferred from the photon to the material
body, or vice versa.


title:
Elementary pathwise methods for nonlinear parabolic and transport type
  SPDE with fractal noise

abstract:
  We survey some of our recent results on existence, uniqueness and regularity
of function solutions to parabolic and transport type partial differential
equations driven by non-differentiable noises. When applied pathwise to random
situations, they provide corresponding statements for stochastic partial
differential equations driven by fractional noises of sufficiently high
regularity order. The approach is based on semigroup theory.


title: Superintegrable systems with spin induced by coalgebra symmetry

abstract:
  A method for deriving superintegrable Hamiltonians with a spin orbital
interaction is presented. The method is applied to obtain a new superintegrable
system in Euclidean space $\mathbb{E}_3$ with the following properties. It
describes a rotationally invariant interaction between a particle of spin
$\frac{1}{2}$ and one of spin 0. Its Hamiltonian commutes with total angular
momentum $\vec{\mathcal{J}}$ and with additional vector integrals of motion
$\vec{X}$, $\vec{Y}$ with components that are third order differential
operators. The integrals of motion form a polynomial algebra under commutation.
The system is exactly solvable (in terms of Laguerre polynomials) and the bound
state energy levels are degenerate and described by a Balmer type formula. When
the spin orbital potential is switched off the system reduces to a hydrogen
atom.


title: Electric current generation in distorted graphene

abstract:
  Graphene-like materials can be effectively described by Quantum
Electrodynamics in (2+1)-dimensions. In a pristine state, these systems exhibit
a symmetry between the nonequivalent Dirac points in the honeycomb lattice.
Realistic samples which include distortions and crystalline anisotropies are
considered through mass gaps of topological and dynamical nature. In this work
we show that the incorporation of an in-plane uniform external magnetic field
on this pseudochiral asymmetric configuration generates a non-dissipative
electric current aligned with the magnetic field: The pseudo chiral magnetic
effect. This scenario resembles the chiral magnetic effect in Quantum
Chromodynamics.


title:
Attractors, black objects, and holographic RG flows in 5d maximal gauged
  supergravities

abstract:
  We perform a systematic search for static solutions in different sectors of
5d $N=8$ supergravities with compact and non-compact gauged R-symmetry groups,
finding new and listing already known backgrounds. Due to the variety of
possible gauge groups and resulting scalar potentials, the maximally symmetric
vacua we encounter in these theories can be Minkowski, de Sitter, or anti-de
Sitter. There exist BPS and non-BPS near-horizon geometries and full solutions
with all these three types of asymptotics, corresponding to black holes,
branes, strings, rings, and other black objects with more exotic horizon
topologies, supported by $U(1)$ and $SU(2)$ charges. The asymptotically AdS$_5$
solutions also have a clear holographic interpretation as RG flows of field
theories on D3 branes, wrapped on compact 2- and 3-manifolds.


title:
Parity nonconservation effect in the dielectronic recombination of
  polarized electrons with heavy He-like ions

abstract:
  We investigate the parity nonconservation (PNC) effect in the dielectronic
recombination (DR) of a polarized electron with a heavy He-like ion into
doubly-excited $((1s 2p_{1/2})_{0} n{\kappa})_{1/2}$ and $\left(\left(1s
2s\right)_{0} n{\kappa}\right)_{1/2}$ states of Li-like ion. We determine the
nuclear charge number $Z$ for which these opposite-parity levels are near to
cross and, therefore, the PNC effect will be significantly enhanced.
Calculations are performed for quantum numbers $n \geq 4$ and $\kappa = \pm 1$.


title: Continuous dependence on the derivative of generalized heat equations

abstract:
  We consider here a generalized heat equation $\partial_t
\rho=\frac{d}{dx}\frac{d}{dW}\rho$, where $W$ is a finite measure on the one
dimensional torus, and $\frac{d}{dW}$ is the Radon-Nikodym derivative with
respect to $W$. Such equation has appeared in different contexts, being related
to physical systems and representing a large class of classical and
non-classical parabolic equations. As a natural assumption on $W$, we require
that the Lebesgue measure is absolutely continuous with respect to $W$. The
main result here presented consists in proving, for a suitable topology, a
continuous dependence of the solution $\rho$ as a function of $W$.


title:
The VLT-FLAMES Tarantula Survey. XIII: On the nature of O Vz stars in 30
  Doradus

abstract:
  AIMS. We test the hypothesis of O Vz stars (characterized by having HeII4686
stronger in absorption than other He lines in their blue-violet spectra) being
at a younger evolutionary stage than are normal O-type dwarfs. METHODS. We have
performed a quantitative spectroscopic analysis of a sample of 38 O Vz and 46 O
V stars, identified by the VLT-FLAMES Tarantula Survey in the 30 Doradus region
of the Large Magellanic Cloud (LMC). We obtained the stellar and wind
parameters of both samples using the FASTWIND stellar atmosphere code and the
IACOB-GBAT grid-based automatic tool. In the framework of a differential study,
we compared the physical and evolutionary properties of both samples, regarding
Teff, logg, logQ and logL. We also investigated the predictions of the FASTWIND
code about the O Vz phenomenon. RESULTS. We find a differential distribution of
objects in terms of effective temperature, with O Vz stars dominant at
intermediate values. The O Vz stars in 30 Doradus tend to be younger and less
luminous, and they have weaker winds than the O V stars, but we also find
examples with ages of 2-4 Myr and with luminosities and winds that are similar
to those of normal O dwarfs. Moreover, the O Vz stars do not appear to have
higher gravities than the O V stars. In addition to effective temperature and
wind strength, our FASTWIND predictions indicate how important it is to take
other stellar parameters (gravity and projected rotational velocity) into
account for correctly interpreting the O Vz phenomenon. CONCLUSIONS. In
general, the O Vz stars appear to be on or very close to the ZAMS, but there
are some examples where the Vz classification does not necessarily imply
extreme youth. In particular, the presence of O Vz stars in our sample at more
evolved phases than expected is likely a consequence of modest O-star winds
owing to the low-metallicity environment of the LMC.


title: Chaos and Turbulent Nucleosynthesis Prior to a Supernova Explosion

abstract:
  Three-dimensional (3D), time dependent numerical simulations, of flow of
matter in stars, now have sufficient resolution to be fully turbulent. The late
stages of the evolution of massive stars, leading up to core collapse to a
neutron star (or black hole), and often to supernova explosion and
nucleosynthesis, are strongly convective because of vigorous neutrino cooling
and nuclear heating. Unlike models based on current stellar evolutionary
practice, these simulations show a chaotic dynamics characteristic of highly
turbulent flow. Theoretical analysis of this flow, both in the
Reynolds-averaged Navier-Stokes (RANS) framework and by simple dynamic models,
show an encouraging consistency with the numerical results. It may now be
possible to develop physically realistic and robust procedures for convection
and mixing which (unlike 3D numerical simulation) may be applied throughout the
long life times of stars. In addition, a new picture of the presupernova stages
is emerging which is more dynamic and interesting (i.e., predictive of new and
newly observed phenomena) than our previous one.


title: Neutron matter under strong magnetic fields: a comparison of models

abstract:
  The equation of state of neutron matter is affected by the presence of a
magnetic field due to the intrinsic magnetic moment of the neutron. Here we
study the equilibrium configuration of this system for a wide range of
densities, temperatures and magnetic fields. Special attention is paid to the
behavior of the isothermal compressibility and the magnetic susceptibility. Our
calculation is performed using both microscopic and phenomenological approaches
of the neutron matter equation of state, namely the Brueckner--Hartree--Fock
(BHF) approach using the Argonne V18 nucleon-nucleon potential supplemented
with the Urbana IX three-nucleon force, the effective Skyrme model in a
Hartree--Fock description, and the Quantum Hadrodynamic formulation with a mean
field approximation. All these approaches predict a change from completely spin
polarized to partially polarized matter that leads to a continuous equation of
state. The compressibility and the magnetic susceptibility show characteristic
behaviors, which reflect that fact. Thermal effects tend to smear out the
sharpness found for these quantities at T=0. In most cases a thermal increase
of 10 MeV is enough to hide the signals of the change of polarization. The set
of densities and magnetic field intensities for which the system changes it
spin polarization is different for each model. However, there is an overall
agreement between the three theoretical descriptions.


title: The Ultraviolet Sky: An Overview from the GALEX Surveys

abstract:
  The Galaxy Evolution Explorer (GALEX) has performed the first surveys of the
sky in the Ultraviolet (UV). Its legacy is an unprecedented database with more
than 200 million source measurements in far-UV (FUV) and near-UV (NUV), as well
as wide-field imaging of extended objects, filling an important gap in our view
of the sky across the electromagnetic spectrum. The UV surveys offer unique
sensitivity for identifying and studying selected classes of astrophysical
objects, both stellar and extra-galactic. We examine the overall content and
distribution of UV sources over the sky, and with magnitude and color. For this
purpose, we have constructed final catalogs of UV sources with homogeneous
quality, eliminating duplicate measurements of the same source. Such catalogs
can facilitate a variety of investigations on UV-selected samples, as well as
planning of observations with future missions.
  We describe the criteria used to build the catalogs, their coverage and
completeness. We included observations in which both the far-UV and near-UV
detectors were exposed; 28,707 fields from the All-Sky Imaging survey (AIS)
cover a unique area of 22,080 square degrees (after we restrict the catalogs to
the central 1-degree diameter of the field), with a typical depth of about
20/21 mag (FUV/NUV, in the AB mag system), and 3,008 fields from the
Medium-depth Imaging Survey (MIS) cover a total of 2,251 square degrees at a
depth of about 22.7mag. The catalogs contain about 71 and 16.6 million sources
respectively. The density of hot stars reflects the Galactic structure, and the
number counts of both Galactic and extra-galactic sources are modulated by the
Milky Way dust extinction, to which the UV data are very sensitive.


title:
Phase-sensitive bichromatic photoresistance in a two-dimensional
  electron gas

abstract:
  We have studied microwave photoresistance in a two-dimensional electron
system subject to two radiation fields (frequencies $\omega_1$ and $\omega_2$)
using quantum kinetic equation. We have found that when $\omega_2/\omega_1= 1 +
2/N$, where $N$ is an integer, and both waves have the same polarization, the
displacement mechanism gives rise to a new, phase-sensitive photoresistance.
This photoresistance oscillates with the magnetic field and can be a good
fraction of the total photoresistance under typical experimental conditions.
The inelastic mechanism, on the other hand, gives zero phase-sensitive
photoresistance if the radiation fields are circularly polarized.


title:
The Nosoi commute: a spatial perspective on the rise of BSL-4
  laboratories in cities

abstract:
  Recent H5N1 influenza research has revived the debate on the storage and
manipulation of potentially harmful pathogens. In the last two decades, new
high biosafety (BSL-4) laboratories entered into operation, raising strong
concerns from the public. The probability of an accidental release of a
pathogen from a BSL-4 laboratory is extremely low, but the corresponding risk
-- defined as the probability of occurrence multiplied by its impact -- could
be significant depending on the pathogen specificities and the population
potentially affected. A list of BSL-4 laboratories throughout the world, with
their location and date of first activity, was established from publicly
available sources. This database was used to estimate the total population
living within a daily commuting distance of BSL-4 laboratories, and to quantify
how this figure changed over time. We show that from 1990 to present, the
population living within the commuting belt of BSL-4 laboratories increased by
a factor of 4 to reach up to 1.8% of the world population, owing to an increase
in the number of facilities and their installation in cities. Europe is
currently hosting the largest population living in the direct vicinity of BSL-4
laboratories, while the recent building of new facilities in Asia suggests that
an important increase of the population living close to BSL-4 laboratories will
be observed in the next decades. We discuss the potential implications in term
of global risk, and call for better pathogen-specific quantitative assessment
of the risk of outbreaks resulting from the accidental release of potentially
pandemic pathogens


title:
Cohomogeneity one actions on some noncompact symmetric spaces of rank
  two

abstract:
  We classify, up to orbit equivalence, the cohomogeneity one actions on the
noncompact duals of the symmetric spaces G_2, SU_3 and the real oriented
two-plane Grassmannians.


title:
On rectifiable spaces and its algebraical equivalents, topological
  algebraic systems and Mal'cel algebras (continuation)

abstract:
  This paper is a natural continuation of paper "On rectifiable spaces and its
algebraical equivalents, topological algebraic systems and Mal'cev algebras"
published in arxiv:1309.4572. Thus we justify the need to present the entire
material in an unified manner. This paper is the continuation of Section 6 from
the first paper. It specifies and corrects the roughest mistakes, incorrect
statements and nonsense of the introduced concepts, which are available in
numerous papers on topological algebraic systems, basically in papers of
Academician Choban M. M. and his disciples.


title: Critical statistics at the mobility edge of QCD Dirac spectra

abstract:
  We examine statistical fluctuation of eigenvalues from the near-edge bulk of
QCD Dirac spectra above the critical temperature. For completeness we start by
reviewing on the spectral property of Anderson tight-binding Hamiltonians as
described by nonlinear sigma models and random matrices, and on the
scale-invariant intermediate spectral statistics at the mobility edge. By
fitting the level spacing distributions, deformed random matrix ensembles which
model multifractality of the wave functions typical of the Anderson
localization transition, are shown to provide an excellent effective
description for such a critical statistics. Next we carry over the above
strategy for the Anderson Hamiltonians to the Dirac spectra. For the staggered
Dirac operators of QCD with 2+1 flavors of dynamical quarks at the physical
point and of SU(2) quenched gauge theory, we identify the precise location of
the mobility edge as the scale-invariant fixed point of the level spacing
distribution. The eigenvalues around the mobility edge are shown to obey
critical statistics described by the aforementioned deformed random matrix
ensembles of unitary and symplectic classes. The best-fitting deformation
parameter for QCD at the physical point turns out to be consistent with the
Anderson Hamiltonian in the unitary class. Finally, we propose a method of
locating the mobility edge at the origin of QCD Dirac spectrum around the
critical temperature, by the use of individual eigenvalue distributions of
deformed chiral random matrices.


title:
Strong converse rates for classical communication over thermal and
  additive noise bosonic channels

abstract:
  We prove that several known upper bounds on the classical capacity of thermal
and additive noise bosonic channels are actually strong converse rates. Our
results strengthen the interpretation of these upper bounds, in the sense that
we now know that the probability of correctly decoding a classical message
rapidly converges to zero in the limit of many channel uses if the
communication rate exceeds these upper bounds. In order for these theorems to
hold, we need to impose a maximum photon number constraint on the states input
to the channel (the strong converse property need not hold if there is only a
mean photon number constraint). Our first theorem demonstrates that Koenig and
Smith's upper bound on the classical capacity of the thermal bosonic channel is
a strong converse rate, and we prove this result by utilizing the structural
decomposition of a thermal channel into a pure-loss channel followed by an
amplifier channel. Our second theorem demonstrates that Giovannetti et al.'s
upper bound on the classical capacity of a thermal bosonic channel corresponds
to a strong converse rate, and we prove this result by relating success
probability to rate, the effective dimension of the output space, and the
purity of the channel as measured by the Renyi collision entropy. Finally, we
use similar techniques to prove that similar previously known upper bounds on
the classical capacity of an additive noise bosonic channel correspond to
strong converse rates.


title: On Solving Manufacturing Cell Formation via Bicluster Editing

abstract:
  This work investigates the Bicluster Graph Editing Problem (BGEP) and how it
can be applied to solve the Manufacturing Cell Formation Problem (MCFP). We
develop an exact method for the BGEP that consists of a Branch-and-Cut approach
combined with a special separation algorithm based on dynamic programming. We
also describe a new preprocessing procedure for the BGEP derived from
theoretical results on vertex distances in the input graph. Computational
experiments performed on randomly generated instances with various levels of
difficulty show that our separation algorithm accelerates the convergence
speed, and our preprocessing procedure is effective for low density instances.
Other contribution of this work is to reveal the similarities between the BGEP
and the MCFP. We show that the BGEP and the MCFP have the same solution space.
This fact leads to the proposal of two new exact approaches for the MCFP based
on mathematical formulations for the BGEP. Both approaches use the grouping
efficacy measure as the objective function. Up to the authors' knowledge, these
are the first exact methods that employ such a measure to optimally solve
instances of the MCFP. The first approach consists of iteratively running
several calls to a parameterized version of the BGEP, and the second is a
linearization of a new fractional-linear model for the MCFP. Computational
experiments performed on instances of the MCFP found in the literature show
that our exact methods for the MCFP are able to prove several previously
unknown optima.


title: On the quantization for self-affine measures on Bedford-McMullen carpets

abstract:
  For a self-affine measure on a Bedford-McMullen carpet we prove that its
quantization dimension exists and determine its exact value. Further, we give
various sufficient conditions for the corresponding upper and lower
quantization coefficient to be both positive and finite. Finally, we compare
the quantization dimension with corresponding quantities derived from the
multifractal temperature function and show that -- different from conformal
systems -- they in general do not coincide.


title: On the randomized complexity of Banach space valued integration

abstract:
  We study the complexity of Banach space valued integration in the randomized
setting. We are concerned with $r$-times continuously differentiable functions
on the $d$-dimensional unit cube $Q$, with values in a Banach space $X$, and
investigate the relation of the optimal convergence rate to the geometry of
$X$. It turns out that the $n$-th minimal errors are bounded by
$cn^{-r/d-1+1/p}$ if and only if $X$ is of equal norm type $p$.


title:
Near-optimal Anomaly Detection in Graphs using Lovasz Extended Scan
  Statistic

abstract:
  The detection of anomalous activity in graphs is a statistical problem that
arises in many applications, such as network surveillance, disease outbreak
detection, and activity monitoring in social networks. Beyond its wide
applicability, graph structured anomaly detection serves as a case study in the
difficulty of balancing computational complexity with statistical power. In
this work, we develop from first principles the generalized likelihood ratio
test for determining if there is a well connected region of activation over the
vertices in the graph in Gaussian noise. Because this test is computationally
infeasible, we provide a relaxation, called the Lovasz extended scan statistic
(LESS) that uses submodularity to approximate the intractable generalized
likelihood ratio. We demonstrate a connection between LESS and maximum
a-posteriori inference in Markov random fields, which provides us with a
poly-time algorithm for LESS. Using electrical network theory, we are able to
control type 1 error for LESS and prove conditions under which LESS is risk
consistent. Finally, we consider specific graph models, the torus, k-nearest
neighbor graphs, and epsilon-random graphs. We show that on these graphs our
results provide near-optimal performance by matching our results to known lower
bounds.


title: Spin-orbit coupling in quantum gases

abstract:
  Spin-orbit coupling links a particle's velocity to its quantum mechanical
spin, and is essential in numerous condensed matter phenomena, including
topological insulators and Majorana fermions. In solid-state materials,
spin-orbit coupling originates from the movement of electrons in a crystal's
intrinsic electric field, which is uniquely prescribed. In contrast, for
ultracold atomic systems, the engineered "material parameters" are tuneable: a
variety of synthetic spin-orbit couplings can be engineered on demand using
laser fields. Here we outline the current experimental and theoretical status
of spin-orbit coupling in ultracold atomic systems, discussing unique features
that enable physics impossible in any other known setting.


title:
Searching for primordial non-Gaussianity in Planck CMB maps using a
  combined estimator

abstract:
  The extensive search for deviations from Gaussianity in cosmic microwave
background radiation (CMB) data is very important due to the information about
the very early moments of the universe encoded there. Recent analyses from
Planck CMB data do not exclude the presence of non-Gaussianity of small
amplitude, although they are consistent with the Gaussian hypothesis. The use
of different techniques is essential to provide information about types and
amplitudes of non-Gaussianities in the CMB data. In particular, we find
interesting to construct an estimator based upon the combination of two
powerful statistical tools that appears to be sensitive enough to detect tiny
deviations from Gaussianity in CMB maps. This estimator combines the Minkowski
functionals with a Neural Network, maximizing a tool widely used to study
non-Gaussian signals with a reinforcement of another tool designed to identify
patterns in a data set. We test our estimator by analyzing simulated CMB maps
contaminated with different amounts of local primordial non-Gaussianity
quantified by the dimensionless parameter fNL. We apply it to these sets of CMB
maps and find \gtrsim 98% of chance of positive detection, even for small
intensity local non-Gaussianity like fNL = 38 +/- 18, the current limit from
Planck data for large angular scales. Additionally, we test the suitability to
distinguish between primary and secondary non-Gaussianities and find out that
our method successfully classifies ~ 95% of the tested maps. Furthermore, we
analyze the foreground-cleaned Planck maps obtaining constraints for
non-Gaussianity at large-angles that are in good agreement with recent
constraints. Finally, we also test the robustness of our estimator including
cut-sky masks and realistic noise maps measured by Planck, obtaining successful
results as well.


title: Lattice-Supported Splines on Polytopal Complexes

abstract:
  We study the module $C^r(\mathcal{P})$ of piecewise polynomial functions of
smoothness $r$ on a pure $n$-dimensional polytopal complex
$\mathcal{P}\subset\mathbb{R}^n$, via an analysis of certain subcomplexes
$\mathcal{P}_W$ obtained from the intersection lattice of the interior
codimension one faces of $\mathcal{P}$. We obtain two main results: first, we
show that in sufficiently high degree, the vector space $C^r_k(\mathcal{P})$ of
splines of degree $\leq k$ has a basis consisting of splines supported on the
$\mathcal{P}_W$ for $k\gg0$. We call such splines lattice-supported. This shows
that an analog of the notion of a star-supported basis for $C^r_k(\Delta)$
studied by Alfeld-Schumaker in the simplicial case holds. Second, we provide a
pair of conjectures, one involving lattice-supported splines, bounding how
large $k$ must be so that $\mbox{dim}_\mathbb{R} C^r_k(\mathcal{P})$ agrees
with the formula given by McDonald-Schenck. A family of examples shows that the
latter conjecture is tight. The proposed bounds generalize known and
conjectured bounds in the simplicial case.


title: No-Sense: Sense with Dormant Sensors

abstract:
  Wireless sensor networks (WSNs) have enabled continuous monitoring of an area
of interest (body, room, region, etc.) while eliminating expensive wired
infrastructure. Typically in such applications, wireless sensor nodes report
the sensed values to a sink node, where the information is required for the
end-user. WSNs also provide the flexibility to the end-user for choosing
several parameters for the monitoring application. For example, placement of
sensors, frequency of sensing and transmission of those sensed data. Over the
years, the advancement in embedded technology has led to increased processing
power and memory capacity of these battery powered devices. However, batteries
can only supply limited energy, thus limiting the lifetime of the network. In
order to prolong the lifetime of the deployment, various efforts have been made
to improve the battery technologies and also reduce the energy consumption of
the sensor node at various layers in the networking stack. Of all the
operations in the network stack, wireless data transmission and reception have
found to consume most of the energy. Hence many proposals found in the
literature target reducing them through intelligent schemes like power control,
reducing retransmissions, etc. In this article we propose a new framework
called Virtual Sensing Framework (VSF), which aims to sufficiently satisfy
application requirements while conserving energy at the sensor nodes.


title: Multiple Shocks

abstract:
  Using gauge/gravity duality, we explore a class of states of two CFTs with a
large degree of entanglement, but with very weak local two-sided correlation.
These states are constructed by perturbing the thermofield double state with
thermal-scale operators that are local at different times. Acting on the dual
black hole geometry, these perturbations create an intersecting network of
shock waves, supporting a very long wormhole. Chaotic CFT dynamics and the
associated fast scrambling time play an essential role in determining the
qualitative features of the resulting geometries.


title: Lattice Boltzmann schemes with relative velocities

abstract:
  In this contribution, a new class of lattice Boltzmann schemes is introduced
and studied. These schemes are presented in a framework that generalizes the
multiple relaxation times method of d'Humi\`eres. They extend also the Geier's
cascaded method. The relaxation phase takes place in a moving frame involving a
set of moments depending on a given relative velocity field. We establish with
the Taylor expansion method that the equivalent partial differential equations
are identical to the ones obtained with the multiple relaxation times method up
to the second order accuracy. The method is then performed to derive the
equivalent equations up to third order accuracy.


title:
Direct spectrum analysis using a threshold detector with application to
  a superconducting circuit

abstract:
  We introduce a new and quantitative theoretical framework for noise spectral
analysis using a threshold detector, which is then applied to a superconducting
device: the Cavity Bifurcation Amplifier (CBA). We show that this new framework
provides direct access to the environmental noise spectrum with a sensitivity
approaching the standard quantum limit of weak continuous measurements. In
addition, the accessible frequency range of the spectrum is, in principle,
limited only by the ring down time of the CBA. This on-chip noise detector is
non-dissipative and works with low probing powers, allowing it to be operated
at low temperatures ($T<15$mK). We exploit this technique for measuring the
frequency fluctuations of the CBA and find a low frequency noise with an
amplitude and spectrum compatible with a dielectric origin.

categories: cond-mat.mes-hall cond-mat.supr-con physics.data-an physics.ins-det


title: Relative continuous K-theory and cyclic homology

abstract:
  We show that for an associative algebra A and its ideal I such that the
I-adic topology on A coincides with the p-adic topology, the relative
continuous K-theory pro-spectrum "lim"K(A_i, IA_i), where A_i :=A/p^i A, is
naturally isogenous to the cyclic chain pro-complex "lim"CC(A_i) (subject to
minor conditions on A). This identification is a continuous version of the
classical Goodwillie isomorphism. The work comes from an attempt to understand
the article of Bloch, Esnault, and Kerz "p-adic deformations of algebraic cycle
classes".


title:
Numerical Reproducibility and Parallel Computations: Issues for Interval
  Algorithms

abstract:
  What is called "numerical reproducibility" is the problem of getting the same
result when the scientific computation is run several times, either on the same
machine or on different machines, with different types and numbers of
processing units, execution environments, computational loads etc. This problem
is especially stringent for HPC numerical simulations. In what follows, the
focus is on parallel implementations of interval arithmetic using
floating-point arithmetic. For interval computations, numerical reproducibility
is of course an issue for testing and debugging purposes. However, as long as
the computed result encloses the exact and unknown result, the inclusion
property, which is the main property of interval arithmetic, is satisfied and
getting bit for bit identical results may not be crucial. Still, implementation
issues may invalidate the inclusion property. Several ways to preserve the
inclusion property are presented, on the example of the product of matrices
with interval coefficients.


title:
GUE minors, maximal Brownian functionals and longest increasing
  subsequences

abstract:
  We present equalities in law between the spectra of the minors of a GUE
matrix and some maximal functionals of independent Brownian motions. In turn,
these results allow to recover the limiting shape (properly centered and
scaled) of the RSK Young diagrams associated with a random word as a function
of the spectra of these minors. Since the length of the top row of the diagrams
is the length of the longest increasing subsequence of the random word, the
corresponding limiting law also follows.


title: Asymptotically efficient prediction for LAN families

abstract:
  In a previous paper (Bosq & Onzon (2012)) we did a first generalization of
the concept of asymptotic efficiency for statistical prediction, i.e. for the
problems where the unknown quantity to infer is not deterministic but random.
However, in some instances, the assumptions we made were not easy to verify.
Here we give proofs of similar results based on quite a different set of
assumptions. The model is required to be a LAN family, which allows to use the
convolution theorem of H\'ajek and Le Cam. The results are applied to the
forecasting of a bivariate Ornstein-Uhlenbeck process, for which the
assumptions of Bosq & Onzon (2012) are tricky to verify.


title: A Uniform Self-Stabilizing Minimum Diameter Spanning Tree Algorithm

abstract:
  We present a uniform self-stabilizing algorithm, which solves the problem of
distributively finding a minimum diameter spanning tree of an arbitrary
positively real-weighted graph. Our algorithm consists in two stages of
stabilizing protocols. The first stage is a uniform randomized stabilizing {\em
unique naming} protocol, and the second stage is a stabilizing {\em MDST}
protocol, designed as a {\em fair composition} of Merlin--Segall's stabilizing
protocol and a distributed deterministic stabilizing protocol solving the
(MDST) problem. The resulting randomized distributed algorithm presented herein
is a composition of the two stages; it stabilizes in $O(n\Delta+{\cal D}^2 + n
\log\log n)$ expected time, and uses $O(n^2\log n + n \log W)$ memory bits
(where $n$ is the order of the graph, $\Delta$ is the maximum degree of the
network, $\cal D$ is the diameter in terms of hops, and $W$ is the largest edge
weight). To our knowledge, our protocol is the very first distributed algorithm
for the (MDST) problem. Moreover, it is fault-tolerant and works for any
anonymous arbitrary network.


title:
The Effect of Eavesdropper's Statistics in Experimental Wireless
  Secret-Key Generation

abstract:
  This paper investigates the role of the eavesdropper's statistics in the
implementation of a practical secret-key generation system. We carefully
conduct the information-theoretic analysis of a secret-key generation system
from wireless channel gains measured with software-defined radios. In
particular, we show that it is inaccurate to assume that the eavesdropper gets
no information because of decorrelation with distance. We also provide a bound
for the achievable secret-key rate in the finite key-length regime that takes
into account the presence of correlated eavesdropper's observations. We
evaluate this bound with our experimental gain measurements to show that
operating with a finite number of samples incurs a loss in secret-key rate on
the order of 20%.


title:
Role of fluctuations and nonlinearities on field emission nanomechanical
  self-oscillators

abstract:
  A theoretical and experimental description of the threshold, amplitude, and
stability of a self-oscillating nanowire in a field emission configuration is
presented. Two thresholds for the onset of self-oscillation are identified, one
induced by fluctuations of the electromagnetic environment and a second
revealed by these fluctuations by measuring the probability density function of
the current. The ac and dc components of the current and the phase stability
are quantified. An ac to dc ratio above 100% and an Allan deviation of 1.3x10-5
at room temperature can be attained. Finally, it is shown that a simple
nonlinear model cannot describe the equilibrium effective potential in the
self-oscillating regime due to the high amplitude of oscillations.


title:
Random walk with heavy tail and negative drift conditioned by its
  minimum and final values

abstract:
  We consider random walks with finite second moment which drifts to $-\infty$
and have heavy tail. We focus on the events when the minimum and the final
value of this walk belong to some compact set. We first specify the associated
probability. Then, conditionally on such an event, we finely describe the
trajectory of the random walk. It yields a decomposition theorem with respect
to a random time giving a big jump whose distribution can be described
explicitly.


title: Quandle Colorings of Knots and Applications

abstract:
  We present a set of 26 finite quandles that distinguish (up to reversal and
mirror image) by number of colorings, all of the 2977 prime oriented knots with
up to 12 crossings. We also show that 1058 of these knots can be distinguished
from their mirror images by the number of colorings by quandles from a certain
set of 23 finite quandles. We study the colorings of these 2977 knots by all of
the 431 connected quandles of order at most 35 found by L. Vendramin. Among
other things, we collect information about quandles that have the same number
of colorings for all of the 2977 knots. For example, we prove that if $Q$ is a
simple quandle of prime power order then $Q$ and the dual quandle $Q^*$ of $Q$
have the same number of colorings for all knots and conjecture that this holds
for all Alexander quandles $Q$. We study a knot invariant based on a quandle
homomorphism $f:Q_1\to Q_0$. We also apply the quandle colorings we have
computed to obtain some new results for the bridge index, the Nakanishi index,
the tunnel number, and the unknotting number. In an appendix we discuss various
properties of the quandles in Vendramin's list. Links to the data computed and
various programs in C, GAP and Maple are provided.


title:
Study of Yang-Mills-Chern-Simons theory in presence of the Gribov
  horizon

abstract:
  The two-point gauge correlation function in Yang--Mills--Chern--Simons theory
in three dimensional Euclidean space is analysed by taking into account the
non-perturbative effects of the Gribov horizon. In this way, we are able to
describe the confinement and de-confinement regimes, which naturally depend on
the topological mass and on the gauge coupling constant of the theory.


title: Proposal for an Experiment to Search for Light Dark Matter at the SPS

abstract:
  Several models of dark matter suggest the existence of dark sectors
consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. These sectors of
particles do not interact with the ordinary matter directly but could couple to
it via gravity. In addition to gravity, there might be another very weak
interaction between the ordinary and dark matter mediated by U'(1) gauge bosons
A' (dark photons) mixing with our photons. In a class of models the
corresponding dark gauge bosons could be light and have the $\gamma$-A'
coupling strength laying in the experimentally accessible and theoretically
interesting region. If such A' mediators exist, their di-electron decays A' ->
e+e- could be searched for in a light-shining-through-a-wall experiment looking
for an excess of events with the two-shower signature generated by a single
high energy electron in the detector. A proposal to perform such an experiment
aiming to probe the still unexplored area of the mixing strength 10^-5 <
$\epsilon$ < 10^-3 and masses M_A' < 100 MeV by using 10-300 GeV electron beams
from the CERN SPS is presented. The experiment can provide complementary
coverage of the parameter space, which is intended to be probed by other
searches. It has also a capability for a sensitive search for A's decaying
invisibly to dark-sector particles, such as dark matter, which could cover a
significant part of the still allowed parameter space. The full running time of
the proposed measurements is requested to be up to several months, and it could
be taken at different SPS secondary beams.


title:
Search for top squark and higgsino production using diphoton Higgs boson
  decays

abstract:
  Results are presented of a search for a "natural" supersymmetry scenario with
gauge mediated symmetry breaking. It is assumed that only the supersymmetric
partners of the top quark (the top squark) and the Higgs boson (higgsino) are
accessible. Events are examined in which there are two photons forming a Higgs
boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of
proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS
experiment, no evidence of a signal is found and lower limits at the 95%
confidence level are set, excluding the top squark mass below 360 to 410 GeV,
depending on the higgsino mass.


title:
Stochastic De Giorgi Iteration and Regularity of Stochastic Partial
  Differential Equation

abstract:
  Under general conditions we show that the solution of a stochastic parabolic
partial differential equation of the form \[ \partial_t u = \mathrm{div} (A
\nabla u) + f(t,x, u) + g_i (t,x,u) \dot{w}^i_t \] is almost surely H\"older
continuous in both space and time variables.


title: On $L^1$-estimates of derivatives of univalent rational functions

abstract:
  We study the growth of the quantity $\int_{\mathbb{T}}|R'(z)|\,dm(z)$ for
rational functions $R$ of degree $n$, which are bounded and univalent in the
unit disk, and prove that this quantity may grow as $n^\gamma$, $\gamma>0$,
when $n\to\infty$. Some applications of this result to problems of regularity
of boundaries of Nevanlinna domains are considered. We also discuss a related
result by Dolzhenko which applies to general (non-univalent) rational
functions.


title: Planck Data Reconsidered

abstract:
  The tension between the best fit parameters derived by the Planck team and a
number of other astronomical measurements suggests either systematics in the
astronomical measurements, systematics in the Planck data, the need for new
physics, or a combination thereof. We re-analyze the Planck data and find that
the $217\,\text{GHz}\times 217\,\text{GHz}$ detector set spectrum used in the
Planck analysis is responsible for some of this tension. We use a map-based
foreground cleaning procedure, relying on a combination of 353 GHz and 545 GHz
maps to reduce residual foregrounds in the intermediate frequency maps used for
cosmological inference. For our baseline data analysis, which uses 47% of the
sky and makes use of both 353 and 545 GHz data for foreground cleaning, we find
the $\Lambda$CDM cosmological parameters $\Omega_c h^2 = 0.1170 \pm 0.0025$,
$n_s = 0.9686 \pm 0.0069$, $H_0 = 68.0 \pm 1.1\,\mathrm{km}
\mathrm{s}^{-1}\mathrm{Mpc}^{-1}$, $\Omega_b h^2 = 0.02197 \pm 0.00026$, $\ln
10^{10}A_s = 3.082 \pm 0.025$, and $\tau = 0.090 \pm 0.013 $. While in broad
agreement with the results reported by the Planck team, these revised
parameters imply a universe with a lower matter density of
$\Omega_m=0.302\pm0.015$, and parameter values generally more consistent with
pre-Planck CMB analyses and astronomical observations. We compare our cleaning
procedure with the foreground modeling used by the Planck team and find good
agreement. The difference in parameters between our analysis and that of the
Planck team is mostly due to our use of cross-spectra from the publicly
available survey maps instead of their use of the detector set cross-spectra
which include pixels only observed in one of the surveys. We show evidence
suggesting residual systematics in the detector set spectra used in the Planck
likelihood code, which is substantially reduced for our spectra.


title: Analytical expansions for parabolic equations

abstract:
  We consider the Cauchy problem associated with a general parabolic partial
differential equation in $d$ dimensions. We find a family of closed-form
asymptotic approximations for the unique classical solution of this equation as
well as rigorous short-time error estimates. Using a boot-strapping technique,
we also provide convergence results for arbitrarily large time intervals.


title: Non-exponential decay in Quantum Mechanics and Quantum Field Theory

abstract:
  We describe some salient features as well as some recent developments
concerning short-time deviations from the exponential decay law in the context
of Quantum Mechanics by using the Lee Hamiltonian approach and Quantum Field
Theory by using relativistic Lagrangians. In particular, the case in which two
decay channels are present is analyzed: the ratio of decay probability
densities, which is a constant equal to the ratio of decay widths in the
exponential limit, shows in general sizable fluctuations which persist also at
long times.


title: Hermitian forms for affine Hecke algebras

abstract:
  We study star operations for Iwahori-Hecke algebras and invariant hermitian
forms for finite dimensional modules over (graded) affine Hecke algebras with a
view towards a unitarity algorithm.


title: Very boosted Higgs in gluon fusion

abstract:
  The Higgs production and decay rates offer a new way to probe new physics
beyond the Standard Model. While dynamics aiming at alleviating the hierarchy
problem generically predict deviations in the Higgs rates, the current
experimental analyses cannot resolve the long- and short-distance contributions
to the gluon fusion process and thus cannot access directly the coupling
between the Higgs and the top quark. We investigate the production of a boosted
Higgs in association with a high-transverse momentum jet as an alternative to
the $t\bar{t}h$ channel to pin down this crucial coupling. Presented first in
the context of an effective field theory, our analysis is then applied to
models of partial compositeness at the TeV scale and of natural supersymmetry.


title:
On correct solvability of a Dirichlet problem for generalized Manjeron
  equation with non-smooth coefficients

abstract:
  In the paper obtained equivalent system of Fredholm integral equations in the
study of the Dirichlet problem for the generalized Manjeron equation with
non-smooth coefficients in non-classical treatment (1), (4). When non-smooth
conditions on the coefficients of the equation in a rectangular region for this
problem posed are found correct solvability conditions in integral form based
on the method of integral representations.


title:
$\Delta I=1/2$ rule for kaon decays derived from QCD infrared fixed
  point

abstract:
  This article gives details of our proposal to replace ordinary chiral
$SU(3)_L\times SU(3)_R$ perturbation theory $\chi$PT$_3$ by 3-flavor
chiral-scale perturbation theory $\chi$PT$_\sigma$. In $\chi$PT$_\sigma$,
amplitudes are expanded at low energies and small $u,d,s$ quark masses about an
infrared fixed point $\alpha^{}_\mathrm{IR}$ of 3-flavor QCD. At
$\alpha^{}_\mathrm{IR}$, the quark condensate $\langle
\bar{q}q\rangle_{\mathrm{vac}} \not= 0$ induces nine Nambu-Goldstone bosons:
$\pi, K, \eta$ and a $0^{++}$ QCD dilaton $\sigma$. Physically, $\sigma$
appears as the $f_{0}(500)$ resonance, a pole at a complex mass with real part
$\lesssim m_K$. The $\Delta I=1/2$ rule for nonleptonic $K$-decays is then a
consequence of $\chi$PT$_\sigma$, with a $K_S\sigma$ coupling fixed by data for
$\gamma\gamma\rightarrow\pi\pi$ and $K_{S} \to \gamma\gamma$. We estimate
$R_\mathrm{IR} \approx 5$ for the nonperturbative Drell-Yan ratio $R =
\sigma(e^{+}e^{-}\rightarrow\mathrm{hadrons})/
  \sigma(e^{+}e^{-}\rightarrow\mu^{+}\mu^{-})$ at $\alpha^{}_\mathrm{IR}$, and
show that, in the many-color limit, $\sigma/f_0$ becomes a narrow $q\bar{q}$
state with planar-gluon corrections. Rules for the order of terms in
$\chi$PT$_\sigma$ loop expansions are derived in Appendix A, and extended in
Appendix B to include inverse-power Li-Pagels singularities due to external
operators. This relates to an observation that, for $\gamma\gamma$ channels,
partial conservation of the dilatation current is not equivalent to
$\sigma$-pole dominance.


title: A Herschel [C II] Galactic plane survey II: CO-dark H2 in clouds

abstract:
  ABRIDGED: Context: HI and CO large scale surveys of the Milky Way trace the
diffuse atomic clouds and the dense shielded regions of molecular hydrogen
clouds. However, until recently, we have not had spectrally resolved C+ surveys
to characterize the photon dominated interstellar medium, including, the H2 gas
without C, the CO-dark H2, in a large sample of clouds. Aims: To use a sparse
Galactic plane survey of the 1.9 THz [C II] spectral line from the Herschel
Open Time Key Programme, Galactic Observations of Terahertz C+ (GOT C+), to
characterize the H2 gas without CO in a statistically significant sample of
clouds. Methods: We identify individual clouds in the inner Galaxy by fitting
[CII] and CO isotopologue spectra along each line of sight. We combine these
with HI spectra, along with excitation models and cloud models of C+, to
determine the column densities and fractional mass of CO-dark H2 clouds.
Results: We identify 1804 narrow velocity [CII] interstellar cloud components
in different categories. About 840 are diffuse molecular clouds with no CO, 510
are transition clouds containing [CII] and 12CO, but no 13CO, and the remainder
are dense molecular clouds containing 13CO emission. The CO-dark H2 clouds are
concentrated between Galactic radii 3.5 to 7.5 kpc and the column density of
the CO-dark H2 layer varies significantly from cloud-to-cloud with an average
9X10^(20) cm-2. These clouds contain a significant fraction of CO-dark H2 mass,
varying from ~75% for diffuse molecular clouds to ~20% for dense molecular
clouds. Conclusions: We find a significant fraction of the warm molecular ISM
gas is invisible in HI and CO, but is detected in [CII]. The fraction of
CO-dark H2 is greatest in the diffuse clouds and decreases with increasing
total column density, and is lowest in the massive clouds.


title: Non-Fermi liquid behavior of large N_B quantum critical metals

abstract:
  The problem of continuous quantum phase transitions in metals involves
critical bosons coupled to a Fermi surface. We solve the theory in the limit of
a large number, N_B, of bosonic flavors, where the bosons transform in the
adjoint representation, while the fermions are in the fundamental
representation of a global SU(N_B) flavor symmetry group. The leading large N_B
solution corresponds to a non-Fermi liquid coupled to Wilson-Fisher bosons. In
a certain energy range, the fermion velocity vanishes - resulting in the
destruction of the Fermi surface. Subleading 1/N_B corrections correspond to a
qualitatively different form of Landau damping of the bosonic critical
fluctuations. We discuss the model in d=3-epsilon but because of the additional
control afforded by large N_B, our results are valid down to d=2. In the limit
epsilon << 1, the large N_B solution is consistent with the RG analysis of Ref.
1.


title: An Indirect Model-Dependent Probe of the Higgs Self-Coupling

abstract:
  The Higgs associated production cross section at an $e^+ e^-$ collider is
indirectly sensitive to the Higgs self-coupling, $h^3$, at next-to-leading
order (NLO). Utilizing this, a new indirect method is proposed for constraining
deviations in the self-coupling below the di-Higgs production threshold in
certain models. Although this indirect constraint is model-dependent, making it
valid only under specific assumptions, meaningful indirect constraints on the
self-coupling may be realized. Specific realistic scenarios where the indirect
constraint applies are discussed and in particular it is shown that in the
well-motivated class of two Higgs-doublet models there exist regions of
parameter space in which the NLO effects from a modified self-coupling dominate
over the LO modifications, demonstrating a concrete scenario in which large
modifications of the Higgs self-coupling may be indirectly constrained using
the proposed method. Other models, such as strongly coupled scenarios, are also
discussed. The indirect method would give valuable constraints on deviations in
the Higgs self-coupling, and would be complementary to the direct measurements
possible with di-Higgs production at other colliders, providing precious
additional information in the effort to unravel the properties of the Higgs
boson.


title: The Structure of Exoplanets

abstract:
  The hundreds of exoplanets that have been discovered in the past two decades
offer a new perspective on planetary structure. Instead of being the archetypal
examples of planets, those of our Solar System are merely possible outcomes of
planetary system formation and evolution, and conceivably not even terribly
common outcomes (although this remains an open question). Here, we review the
diverse range of interior structures that are known to, and speculated to,
exist in exoplanetary systems -- from mostly degenerate objects that are more
than 10 times as massive as Jupiter, to intermediate-mass Neptune-like objects
with large cores and moderate hydrogen/helium envelopes, to rocky objects with
roughly the mass of the Earth.


title: Higgs Bosons from Top Quark Decays

abstract:
  In light of the discovery of a Standard Model (SM)-like Higgs boson ($h$) at
the LHC, we investigate the top quark to Higgs boson transition $t\rightarrow
W^{*}bh$, which is the leading $t\to h$ decay mode in the SM. We find the decay
branching fraction to be $1.80\times 10^{-9}$. In comparison, the two-body,
loop-induced $t\rightarrow ch$ transition occurs at $\sim10^{-14}$ in the SM.
We consider the consequences of gauge invariant dimension-6 operators affecting
the $t\bar{t}h$ interaction and find that the decay branching fraction may be
increased by a factor of two within current constraints on the coupling
parameters from collider experiments. We also extend the calculation to the
CP-conserving Type I and Type II Two Higgs Doublet Models (2HDM), including
both CP-even and CP-odd Higgs bosons. For neutral scalar masses at about $100$
GeV, the decay rates can be several times larger than the SM result in the
allowed range of model parameters. Observation prospects at present and future
colliders are briefly addressed.


title: Composite strongly interacting dark matter

abstract:
  It has been suggested that cold dark matter (CDM) has difficulties in
explaining tentative evidence for noncuspy halo profiles in small galaxies, and
the low velocity dispersions observed in the largest Milky Way satellites ("too
big to fail" problem). Strongly self-interacting dark matter has been noted as
a robust solution to these problems. The elastic cross sections required are
much larger than predicted by generic CDM models, but could naturally be of the
right size if dark matter is composite. We explore in a general way the
constraints on models where strongly interacting CDM is in the form of dark
"atoms" or "molecules," or bound states of a confining gauge interaction
("hadrons"). These constraints include considerations of relic density, direct
detection, big bang nucleosynthesis, the cosmic microwave background, and LHC
data.


title:
LUX Constraints on Magnetic Dark Matter in the $S\bar{E} \chi$y Model
  with(out) Naturality

abstract:
  We study phenomenological constraints in a simple $S\bar{E} \chi$y extension
of the Standard Model (SM) with a 125 GeV Higgs, a vector-like heavy electron
$(E)$, a complex scalar electron $(S)$ and a standard model singlet Dirac
fermion $(\chi)$. The interactions among the dark matter candidate $\chi$ and
the standard model particles occur via loop-induced processes involving the
Yukawa interaction $S\bar{E} \chi$y. The model is an explicit perturbative
realization of so-called magnetic dark matter. The field content allows for a
cancelation of quadratic divergences in the scalar masses at one-loop, a
phenomenon which we refer to as perturbative naturality. The basic model is
constrained dominantly by direct detection experiments and its parameter space
can be nearly entirely covered by up-coming ton-scale direct detection
experiments. We conclude this work by discussing different variations of the
model.


title:
A Method to Identify the Boundary Between Rocky and Gaseous Exoplanets
  from Tidal Theory and Transit Durations

abstract:
  The determination of an exoplanet as rocky is critical for the assessment of
planetary habitability. Observationally, the number of small-radius, transiting
planets with accompanying mass measurements is insufficient for a robust
determination of the transitional mass or radius. Theoretically, models predict
that rocky planets can grow large enough to become gas giants when they reach
~10 Earth-masses, but the transitional mass remains unknown. Here I show how
transit data, interpreted in the context of tidal theory, can reveal the
critical radius that separates rocky and gaseous exoplanets. Standard tidal
models predict that rocky exoplanets' orbits are tidally circularized much more
rapidly than gaseous bodies', suggesting the former will tend to be found on
circular orbits at larger semi-major axes than the latter. Well-sampled
transits can provide a minimum eccentricity of the orbit, allowing a
measurement of this differential circularization. I show that this effect
should be present in the data from the Kepler spacecraft, but is not apparent.
Instead, it appears that there is no evidence of tidal circularization at any
planetary radius, probably because the publicly-available data, particularly
the impact parameters, are not accurate enough. I also review the bias in the
transit duration toward values that are smaller than that of planets on
circular orbits, stressing that the azimuthal velocity of the planet determines
the transit duration. The ensemble of Kepler planet candidates may be able to
determine the critical radius between rocky and gaseous exoplanets, tidal
dissipation as a function of planetary radius, and discriminate between tidal
models.


title:
Identifying clustering at high redshift through actively star-forming
  galaxies

abstract:
  Identifying galaxy clustering at high redshift (i.e. z > 1) is essential to
our understanding of the current cosmological model. However, at increasing
redshift, clusters evolve considerably in star-formation activity and so are
less likely to be identified using the widely-used red sequence method. Here we
assess the viability of instead identifying high redshift clustering using
actively star-forming galaxies (SMGs associated with over-densities of
BzKs/LBGs). We perform both a 2- and 3-D clustering analysis to determine
whether or not true (3D) clustering can be identified where only 2D data are
available. As expected, we find that 2D clustering signals are weak at best and
inferred results are method dependant. In our 3D analysis, we identify 12 SMGs
associated with an over-density of galaxies coincident both spatially and in
redshift - just 8% of SMGs with known redshifts in our sample. Where an SMG in
our target fields lacks a known redshift, their sightline is no more likely to
display clustering than blank sky fields; prior redshift information for the
SMG is required to identify a true clustering signal. We find that the strength
of clustering in the volume around typical SMGs, while identifiable, is not
exceptional. However, we identify a small number of highly clustered regions,
all associated with an SMG. The most notable of these, surrounding
LESSJ033336.8-274401, potentially contains an SMG, a QSO and 36 star-forming
galaxies (a > 20sig over-density) all at z~1.8. This region is highly likely to
represent an actively star-forming cluster and illustrates the success of using
star-forming galaxies to select sites of early clustering. Given the increasing
number of deep fields with large volumes of spectroscopy, or high quality and
reliable photometric redshifts, this opens a new avenue for cluster
identification in the young Universe.


title:
The SCUBA-2 Cosmology Legacy Survey: Ultraluminous star-forming galaxies
  in a z=1.6 cluster

abstract:
  We analyse new SCUBA-2 submillimeter and archival SPIRE far-infrared imaging
of a z=1.62 cluster, Cl0218.3-0510, which lies in the UKIDSS/UDS field of the
SCUBA-2 Cosmology Legacy Survey. Combining these tracers of obscured star
formation activity with the extensive photometric and spectroscopic information
available for this field, we identify 31 far-infrared/submillimeter-detected
probable cluster members with bolometric luminosities >1e12 Lo and show that by
virtue of their dust content and activity, these represent some of the reddest
and brightest galaxies in this structure. We exploit Cycle-1 ALMA submillimeter
continuum imaging which covers one of these sources to confirm the
identification of a SCUBA-2-detected ultraluminous star-forming galaxy in this
structure. Integrating the total star-formation activity in the central region
of the structure, we estimate that it is an order of magnitude higher (in a
mass-normalised sense) than clusters at z~0.5-1. However, we also find that the
most active cluster members do not reside in the densest regions of the
structure, which instead host a population of passive and massive, red
galaxies. We suggest that while the passive and active populations have
comparable near-infrared luminosities at z=1.6, M(H)~-23, the subsequent
stronger fading of the more active galaxies means that they will evolve into
passive systems at the present-day which are less luminous than the descendants
of those galaxies which were already passive at z~1.6 (M(H)~-20.5 and
M(H)~-21.5 respectively at z~0). We conclude that the massive galaxy population
in the dense cores of present-day clusters were already in place at z=1.6 and
that in Cl0218.3-0510 we are seeing continuing infall of less extreme, but
still ultraluminous, star-forming galaxies onto a pre-existing structure.


title:
The relation between accretion rates and the initial mass function in
  hydrodynamical simulations of star formation

abstract:
  We analyse a hydrodynamical simulation of star formation. Sink particles in
the simulations which represent stars show episodic growth, which is presumably
accretion from a core that can be regularly replenished in response to the
fluctuating conditions in the local environment. The accretion rates follow
$\dot{m} \propto m^{2/3}$, as expected from accretion in a gas-dominated
potential, but with substantial variations over-laid on this. The growth times
follow an exponential distribution which is tapered at long times due to the
finite length of the simulation. The initial collapse masses have an
approximately lognormal distribution with already an onset of a power-law at
large masses. The sink particle mass function can be reproduced with a
non-linear stochastic process, with fluctuating accretion rates $\propto
m^{2/3}$, a distribution of seed masses and a distribution of growth times. All
three factors contribute equally to the form of the final sink mass function.
We find that the upper power law tail of the IMF is unrelated to Bondi-Hoyle
accretion.


title:
Higgs-radion unification: radius stabilization by an SU(2) bulk doublet
  and the 126 GeV scalar

abstract:
  We investigate a Randall-Sundrum model with an SU(2) doublet propagating in
the bulk. Upon calculating its gravitational effect we find that a stabilized
radius can be generated without the use of an additional scalar, as needed for
example in the Goldberger-Wise (GW) mechanism, and with no additional
fine-tuning other than the inescapable one due to the cosmological constant;
similar tuning is also present in the GW mechanism. The lowest scalar
excitation in this scenario, the counterpart of the radion of the GW mechanism,
has both radion-like and Higgs-like couplings to the SM fields. It, thus, plays
a dual role and we, therefore, denote it as the "Higgs-radion" ($h_r$). As
opposed to the GW radion case, our Higgs-radion is found to be compatible with
the 126 GeV scalar recently discovered at the LHC, at the level of $1\sigma$,
with a resulting $95\%$ CL bound on the KK-gluon mass of: $4.48~TeV<M_{KKG}<
5.44~TeV$. An important consequence of our setup should be accentuated: the
radion of the traditional RS scenarios simply does not exist, so that our
Higgs-radion is not the conventional mixed state between the GW radion and the
Higgs.


title: How Discord underlies the Noise Resilience of Quantum Illumination

abstract:
  The benefits of entanglement can outlast entanglement itself. In quantum
illumination, entanglement is employed to better detect reflecting objects in
environments so noisy that all entanglement is destroyed. Here, we show that
quantum discord - a more resilient form of quantum correlations - explains the
resilience of quantum illumination. We introduce a quantitative relation
between the performance gain in quantum illumination and the amount of discord
used to encode information about the presence or absence of a reflecting
object. This highlights discord's role preserving the benefits of entanglement
in entanglement breaking noise.


title:
A High-Frequency Doppler Feature in the Power Spectra of Simulated GRMHD
  Black Hole Accretion Disks

abstract:
  Black hole binaries exhibit a wide range of variability phenomena, from
large-scale state changes to broadband noise and quasi-periodic oscillations,
but the physical nature of much of this variability is poorly understood. We
examine the variability properties of three GRMHD simulations of thin accretion
disks around black holes of varying spin, producing light curves and power
spectra as would be seen by observers. We find that the simulated power spectra
show a broad feature at high frequency, which increases in amplitude with the
inclination of the observer. We show that this high-frequency feature is a
product of the Doppler effect and that its location is a function of the mass
and spin of the black hole. This Doppler feature demonstrates that power
spectral properties of the accretion disk can be tied to, and potentially used
to determine, physical properties of the black hole.


title:
Quantum critical charge response from higher derivatives: is more
  different?

abstract:
  We present new possibilities for the charge response in the quantum critical
regime in 2+1D using holography, and compare them with field theory and recent
quantum Monte Carlo results. We show that a family of (infinitely many) higher
derivative terms in the gravitational bulk leads to behavior far richer than
what was previously obtained. For example, we prove that the conductivity
becomes unbounded, undermining previously obtained constraints. We further find
a non-trivial and infinite set of theories that have a self-dual conductivity.
Particle-vortex or S duality plays a key role; notably, it maps theories with a
finite number of bulk terms to ones with an infinite number. Many properties
such as sum rules and stability conditions are proved.


title:
Two new AM Canum Venaticorum binaries from the Sloan Digital Sky Survey
  III

abstract:
  The AM Canum Venaticorum (AM CVn) binaries are a rare group of ultra-short
period, mass-transferring white dwarf binaries, some of which may be Type Ia
supernova progenitors. More than a third of the total known population of AM
CVn binaries have been discovered via the Sloan Digital Sky Survey (SDSS).
Here, we discuss our search for new AM CVns in the SDSS spectroscopic data
base, and present two new AM CVns discovered in SDSS-III spectroscopy, SDSS
J113732.32+405458.3 and SDSS J150551.58+065948.7. The AM CVn binaries exhibit a
connection between their spectral appearance and their orbital period, the
spectra of these two new AM CVns suggest that they may be long period systems.
Using the radial velocity variations of the emission lines, we measure a
possible orbital period of 59.6 +/- 2.7 minutes for SDSS J113732.32+405458.3.
Since our search of SDSS spectroscopy has revealed only these two new systems,
it is unlikely that a large population of AM CVn binaries have been missed, and
their discovery should have little effect on previous calculations of the AM
CVn space density.


title:
The dependency of AGN infrared color-selection on source luminosity and
  obscuration: An observational perspective in CDFS and COSMOS

abstract:
  AIMS. This work addresses the AGN IR-selection dependency on intrinsic source
luminosity and obscuration, in order to identify and charaterise biases which
could affect conclusions in studies. METHODS. We study IR-selected AGN in the
Chandra Deep Field South (CDFS) survey and in the Cosmological Survey (COSMOS).
The AGN sample is divided into low and high X-ray luminosity classes, and into
unobscured (type-1) and obscured (type-2) classes by means of X-ray and optical
spectroscopy data. Specifically in the X-rays regime, we adopt the intrinsic
luminosity taking into account the estimated column density (N_H). We also take
the chance to highlight important differences resulting from adopting different
methods to assess AGN obscuration. RESULTS. In agreement with previous studies,
we also find that AGN IR-selection efficiency shows a decrease with decreasing
source AGN X-ray luminosity. For the intermediate-luminosity AGN population
(43.3<~log(L_X[erg/s])<~44$), the efficiency also worsens with increasing
obscuration. The same sample also shows an evolution with cosmic time of the
obscured fraction at the highest X-ray luminosities, independently of adopted
type-1/type-2 classification method. CONCLUSIONS. We confirm that AGN
IR-selection is genuinely biased toward unobscured AGN, but only at
intermediate luminosities. At the highest luminosities, where AGN IR-selection
is more efficient, there is no obscuration bias. We show that type-1 AGN are
intrinsically more luminous than type-2 AGN only at z<~1.6, thus resulting in
more type-1 AGN being selected the shallower the IR survey is. [ABRIDGED:
Conclusion on survey strategy. See manuscript.] Finally, when the James Webb
Space Telescope comes online, the broad-band filters 2.0um, 4.4um, 7.7um, and
18um will be key to disentangle AGN from non-AGN dominated SEDs at depths where
spectroscopy becomes impractical.


title:
Increased insolation threshold for runaway greenhouse processes on Earth
  like planets

abstract:
  Because the solar luminosity increases over geological timescales, Earth
climate is expected to warm, increasing water evaporation which, in turn,
enhances the atmospheric greenhouse effect. Above a certain critical
insolation, this destabilizing greenhouse feedback can "runaway" until all the
oceans are evaporated. Through increases in stratospheric humidity, warming may
also cause oceans to escape to space before the runaway greenhouse occurs. The
critical insolation thresholds for these processes, however, remain uncertain
because they have so far been evaluated with unidimensional models that cannot
account for the dynamical and cloud feedback effects that are key stabilizing
features of Earth's climate. Here we use a 3D global climate model to show that
the threshold for the runaway greenhouse is about 375 W/m$^2$, significantly
higher than previously thought. Our model is specifically developed to quantify
the climate response of Earth-like planets to increased insolation in hot and
extremely moist atmospheres. In contrast with previous studies, we find that
clouds have a destabilizing feedback on the long term warming. However,
subsident, unsaturated regions created by the Hadley circulation have a
stabilizing effect that is strong enough to defer the runaway greenhouse limit
to higher insolation than inferred from 1D models. Furthermore, because of
wavelength-dependent radiative effects, the stratosphere remains cold and dry
enough to hamper atmospheric water escape, even at large fluxes. This has
strong implications for Venus early water history and extends the size of the
habitable zone around other stars.


title: On the integration of fields and quanta in time dependent backgrounds

abstract:
  Field theories with global continuous symmetries may admit configurations in
which time translation invariance is broken by the movement of homogeneous
background fields evolving along the flat directions implied by the symmetries.
In this context, the field fluctuations along the broken symmetry are well
parametrized by a Goldstone boson field that may non-trivially interact with
other fields present in the theory. These interactions violate Lorentz
invariance as a result of the broken time translation invariance of the
background, producing a mixing between the field content and the particle
spectrum of the theory. In this article we study the effects of such
interactions on the low energy dynamics of the Goldstone boson quanta, paying
special attention to the role of the particle spectrum of the theory. By
studying the particular case of a canonical two-field model with a mexican-hat
potential, we analyze the derivation of the low energy effective field theory
for the Goldstone boson, and discuss in detail the distinction between
integrating fields v/s integrating quanta, to finally conclude that they are
equivalent. In addition, we discuss the implications of our analysis for the
study of systems where time translation invariance is broken, such as cosmic
inflation and time crystals.


title:
Density of Saturated Nuclear Matter at Large $N_{c}$ and Heavy Quark
  Mass Limits

abstract:
  We exhibit the existence of stable, saturated nuclear matter in the large
$N_{c}$ and heavy quark mass limits of QCD. In this limit, baryons (with the
same spin flavor structure) interact at leading order in $N_{c}$ via a
repulsive interaction due to the Pauli exclusion principle and at subleading
order in $1/N_c$ via the exchange of glueballs. Assuming that the lightest
glueball is a scalar, which implies that the subleading baryon interaction is
attractive, we find that nuclear matter saturates since the subleading
attractive interaction is longer ranged than the leading order repulsive one.
We find that the saturated matter is in the form of a crystal with either a
face-centered cubic or a hexagonal-close-packed symmetry with baryon densities
of $\mathcal{O}((\, \tilde{\alpha}_{s} m_q (\ln
(N_{c}m_{q}\Lambda_{\textrm{QCD}}^{-1}))^{-1})^3 )$. Remarkably, the leading
order expression for the density of saturated nuclear matter is independent of
the lighest glueball mass and scalar-glueball-baryon coupling in the extreme
large $N_{c}$ limit or heavy quark limit (or both), which we define precisely
in this work.


title: Collisional energy loss above the critical temperature in QCD

abstract:
  We compute the collisional energy loss for a heavy quark above the critical
temperature in Quantum ChromoDynamics (QCD). We work in the semi Quark-Gluon
Plasma, which assumes that this region is dominated by the non-trivial holonomy
of the thermal Wilson line. Relative to the result to leading order in
perturbation theory, at a fixed value of the coupling constant we generically
we find that collisional energy loss is suppressed by powers of the Polyakov
loop, l < 1. For small values of the loop, this suppression is linear for the
scattering off of light quarks, and quadratic for the scattering off of gluons,
or for Compton scattering.


title:
Locally enhanced conductivity due to the tetragonal domain structure in
  LaAlO$_{3}$/SrTiO$_{3}$ heterointerfaces

abstract:
  The ability to control materials properties through interface engineering is
demonstrated by the appearance of conductivity at the interface of certain
insulators, most famously the {001} interface of the band insulators
LaAlO$_{3}$ and TiO$_{2}$-terminated SrTiO$_{3}$ (STO). Transport and other
measurements in this system show a plethora of diverse physical phenomena. To
better understand the interface conductivity, we used scanning superconducting
quantum interference device microscopy to image the magnetic field locally
generated by current in an interface. At low temperature, we found that the
current flowed in conductive narrow paths oriented along the crystallographic
axes, embedded in a less conductive background. The configuration of these
paths changed on thermal cycling above the STO cubic-to-tetragonal structural
transition temperature, implying that the local conductivity is strongly
modified by the STO tetragonal domain structure. The interplay between
substrate domains and the interface provides an additional mechanism for
understanding and controlling the behaviour of heterostructures.


title: Persistent C II Absorption in the Normal Type Ia Supernova 2002fk

abstract:
  We present well-sampled $UBVRIJHK$ photometry of SN 2002fk starting 12 days
before maximum light through 122 days after peak brightness, along with a
series of 15 optical spectra from -4 to +95 days since maximum. Our
observations show the presence of C II lines in the early-time spectra of SN
2002fk, expanding at ~11,000 km s$^{-1}~$ and persisting until ~8 days past
maximum light with a velocity of $\sim$9,000 km s$^{-1}~$. SN 2002fk is
characterized by a small velocity gradient of $\dot v_{Si~II}=26$ km s$^{-1}$
day$^{-1}$, possibly caused by an off-center explosion with the ignition region
oriented towards the observer. The connection between viewing angle of an
off-center explosion and the presence of C II in the early time spectrum
suggests that the observation of C II could be also due to a viewing angle
effect. Adopting the Cepheid distance to NGC 1309 we provide the first $H_{0}$
value based on near-IR measurements of a Type Ia supernova between 63.0$\pm$
0.8 ($\pm$ 2.8 systematic) and 66.7$\pm$1.0 ($\pm$ 3.5 systematic) km/s/Mpc,
depending on the absolute magnitude/decline rate relationship adopted. It
appears that the near-IR yields somewhat lower (6-9 %) $H_0$ values than the
optical. It is essential to further examine this issue by (1) expanding the
sample of high-quality near-IR light curves of SNe in the Hubble flow, and (2)
increasing the number of nearby SNe with near-IR SN light curves and precise
Cepheid distances, which affords the promise to deliver a more precise
determination of $H_0$.


title: Local Electrostatic Imaging of Striped Domain Order in LaAlO3/SrTiO3

abstract:
  The emerging field of complex oxide interfaces is generically built on one of
the most celebrated substrates - strontium titanate (SrTiO3). This material
hosts a range of phenomena, including ferroelasticity, incipient
ferroelectricity, and most puzzlingly, contested giant piezoelectricity.
Although these properties may markedly influence the oxide interfaces,
especially on microscopic length scales, the lack of local probes capable of
studying such buried systems has left their effects largely unexplored. Here we
use a scanning charge detector - a nanotube single-electron transistor - to
noninvasively image the electrostatic landscape and local mechanical response
in the prototypical LaAlO3/SrTiO3 system with unprecedented sensitivity. Our
measurements reveal that on microscopic scales SrTiO3 exhibits large anomalous
piezoelectricity with curious spatial dependence. Through electrostatic imaging
we unravel the microscopic origin for this extrinsic piezoelectricity,
demonstrating its direct, quantitative connection to the motion of locally
ordered tetragonal domains under applied gate voltage. These domains create
striped potential modulations that can markedly influence the two-dimensional
electron system at the conducting interface. Our results have broad
implications to all complex oxide interfaces built on SrTiO3 and demonstrate
the importance of microscopic structure to the physics of electrons at the
LaAlO3/SrTiO3 interface.


title:
Interfaces between buckling phases in Silicene: Ab initio density
  functional theory calculations

abstract:
  The buckled structure of silicene leads to the possibility of new kinds of
line defects that separate regions with reversed buckled phases. In the present
work we show that these new grain boundaries have very low formation energies,
one order of magnitude smaller than grain boundaries in graphene. These defects
are stable along different orientations, and they can all be differentiated by
STM images. All these defects present local dimerization between the Si atoms,
with the formation of $\pi$-bonds. As a result, these defects are preferential
adsorption sites when compared to the pristine region. Thus, the combination of
low formation energy and higher reactivity of these defects may be cleverly
used to design new nano-structures embedded in silicene.


title:
Worst-Case Performance Analysis of Some Approximation Algorithms for
  Minimizing Makespan and Flow-Time

abstract:
  In 1976, Coffman and Sethi conjectured that a natural extension of LPT list
scheduling to the bicriteria scheduling problem of minimizing makespan over
flowtime optimal schedules, called LD algorithm, has a simple worst-case
performance bound: (5m-2)/(4m-1), where m is the number of machines. We study
structure of potential minimal counterexamples to this conjecture and prove
that the conjecture holds for the cases (i) n > 5m, (ii) m = 2, (iii) m = 3,
and (iv) m greater than or equal to 4, n less than or equal to 3m, where n is
the number of jobs. We further conclude that to verify the conjecture, it
suffices to analyze the following case: for every m greater than or equal to 4,
n is either equal to 4m or 5m.


title: No Holography for Eternal AdS Black Holes

abstract:
  It is generally believed that the eternal AdS black hole is dual to two
conformal field theories with compact spatial sections that are together in a
thermofield double state. We argue that this proposal is incorrect, and by
extension so are the "entanglement=geometry" proposal of Van Raamsdonk and
"ER=EPR" proposal of Maldacena and Susskind. We show that in the bulk there is
an interaction needed between the two halves of the Hilbert space for
connectivity across the horizon; however, there is no such interaction between
the CFTs. This rules out the possibility of the dual to the CFTs being the
eternal AdS black hole. We argue the correct dual "geometries" resemble the
exterior of the black hole outside the stretched horizon but cap off before the
global horizon. This disallows the possibility of a shared future (and past)
wedge where Alice falling from one side can meet Bob falling from the other. We
expect that in the UV complete theory the aforementioned caps will be
fuzzballs.


title: A Distributed Deadlock Free Quorum Based Algorithm for Mutual Exclusion

abstract:
  Quorum based mutual exclusion algorithms enjoy many advantages such as low
message complexity and high failure resiliency. The use of quorums is a well
known approach to achieving mutual exclusion in distributed environments.
Several distributed based quorum mutual exclusion was presented.


title: The Chiral Magnetic Effect and Anomaly-Induced Transport

abstract:
  The Chiral Magnetic Effect (CME) is the phenomenon of electric charge
separation along the external magnetic field that is induced by the chirality
imbalance. The CME is a macroscopic quantum effect - it is a manifestation of
the chiral anomaly creating a collective motion in Dirac sea. Because the
chirality imbalance is related to the global topology of gauge fields, the CME
current is topologically protected and hence non-dissipative even in the
presence of strong interactions. As a result, the CME and related quantum
phenomena affect the hydrodynamical and transport behavior of systems
possessing chiral fermions, from the quark-gluon plasma to chiral materials.
The goal of the present review is to provide an elementary introduction into
the main ideas underlying the physics of CME, a historical perspective, and a
guide to the rapidly growing literature on this topic.


title: Market Impact Paradoxes

abstract:
  The market impact (MI) of Volume Weighted Average Price (VWAP) orders is a
convex function of a trading rate, but most empirical estimates of transaction
cost are concave functions. How is this possible? We show that isochronic
(constant trading time) MI is slightly convex, and isochoric (constant trading
volume) MI is concave. We suggest a model that fits all trading regimes and
guarantees no-dynamic-arbitrage.


title: Expanding the Grammar of Biology

abstract:
  We metaphorically call "Grammar of Biology" a small field of genomic
research, whose main objective is to search for intrinsic DNA sequence
properties. Erwin Chargaff inaugurated it back in 50s, but since then little
progress has been made. It remained almost neglected until early 90s, when
Vinayakumar V. Prabhu made a major contribution determining the Symmetry
Principle. Remarkably, different sciences have contributed for its development,
for instance, Chargaff used his Chemistry background to discover the so-called
Chargaff's rules; taking advantage of several publicly available genomic
sequences, and through Computational and Statistical analyses, Prabhu
identified the Symmetry Principle and, recently, using a Mathematical approach,
we have discovered four new Generalized Chargaff's rules. Our work has expanded
the "Grammar of Biology", and created the conceptual and theoretical framework
necessary to further developments.


title: Holographic charge transport in 2+1 dimensions at finite $N$

abstract:
  We study holographic charge transport in (2+1) dimensions at finite $N$,
whose dual gravity background is given by perturbative black hole solution in
Einstein theory plus cubic terms of Weyl tensor. We consider the higher
derivative corrections to the standard Maxwell action, given by the interacting
terms between the Weyl tensor and the field strength. We calculate the DC
conductivity by using both the membrane paradigm and the Kubo's formula and
find precise agreement. We compute the AC conductivity and find an analog of
the crossover from `metal' to `bad metal' in the low frequency limit. Moreover,
the conductivity becomes a constant in the large frequency limit. We derive two
universal relations for the Green's functions and observe that they are exactly
the same as the infinite $N$ counterparts.


title:
Asymptotic theory of sequential detection and identification in the
  hidden Markov models

abstract:
  We consider a unified framework of sequential change-point detection and
hypothesis testing modeled by means of hidden Markov chains. One observes a
sequence of random variables whose distributions are functionals of a hidden
Markov chain. The objective is to detect quickly the event that the hidden
Markov chain leaves a certain set of states, and to identify accurately the
class of states into which it is absorbed. We propose computationally tractable
sequential detection and identification strategies and obtain sufficient
conditions for the asymptotic optimality in two Bayesian formulations.
Numerical examples are provided to confirm the asymptotic optimality and to
examine the rate of convergence.


title: More AdS_3 correlators

abstract:
  We compute three-point functions for the $SL(2,\mathbb R)$-WZNW model. After
reviewing the case of the two-point correlator, we compute spectral flow
preserving and nonpreserving correlation functions in the space-time picture
involving three vertex operators carrying an arbitrary amount of spectral flow.
When only one or two insertions have nontrivial spectral flow numbers, the
method we employ allows us to find expressions without any constraint on the
spin values. Unlike these cases, the same procedure restrains the possible spin
configurations when three vertices belong to nonzero spectral flow sectors. We
perform several consistency checks on our results. In particular, we verify
that they are in complete agreement with previously computed correlators
involving states carrying a single unit of spectral flow.


title: Symplectic cohomology and Viterbo's theorem

abstract:
  This is a research monograph on symplectic cohomology (disguised as an
advanced graduate textbook), which provides a construction of this version of
Hamiltonian Floer cohomology for cotangent bundles of closed manifolds. The
focus is on the aspects of the theory that have been neglected in the
literature: (1) the base is not assumed to be orientable or Spin, (2) local
systems on the free loop space are used to define twisted versions of Floer
cohomology, (3) a (twisted) Batalin-Vilkovisky structure is constructed, and
(4) the BV relation is verified. In this setting (i.e. with all the appropriate
twists), a proof of Viterbo's theorem relating symplectic cohomology to the
homology of the free loop space is provided, and we show that this map respects
the BV structure. Viterbo's theorem is proved by constructing three different
maps relating the two sides, and proving that two of the compositions are
isomorphisms by using degenerations of moduli spaces of genus 0 Riemann
surfaces with boundary. Two of the maps constructed are new, and use ideas
inspired by a Lagrangian version of family Floer cohomology.


title:
Multi-mJ, kHz, 2.1-$\mu$m OPCPA for high-flux soft X-ray high-harmonic
  radiation

abstract:
  We report on a multi-mJ 2.1-$\mu$m OPCPA system operating at a 1-kHz
repetition rate, pumped by a picosecond cryogenic Yb:YAG pump laser, and the
phase-matched high-flux high-harmonic soft X-ray generation.


title:
Optical damage threshold of Au nanowires in strong femtosecond laser
  fields

abstract:
  Ultrashort, intense light pulses permit the study of nanomaterials in the
optical non-linear regime, potentially leading to optoelectronics that operate
in the petahertz domain. These non-linear regimes are often present just below
the damage threshold thus requiring the careful tuning of laser parameters to
avoid the melting and disintegration of the materials. Detailed studies of the
damage threshold of nanoscale materials are therefore needed. We present
results on the damage threshold of Au nanowires when illuminated by intense
femtosecond pulses. These nanowires were synthesized with the directed
electrochemical nanowire assembly (DENA) process in two configurations: (1)
free-standing Au nanowires on W electrodes and (2) Au nanowires attached to
fused silica slides. In both cases the wires have a single-crystalline
structure. For laser pulses with durations of 108 fs and 32 fs at 790 nm at a
repetition rate of 2 kHz, we find that the free-standing nanowires melt at
intensities close to 3 TW/cm$^2$ and 7.5 TW/cm$^2$, respectively. The Au
nanowires attached to silica slides melt at slightly higher intensities, just
above 10 TW/cm$^2$ for 32 fs pulses. Our results can be explained with an
electron-phonon interaction model that describes the absorbed laser energy and
subsequent heat conduction across the wire.


title: Polynomial chaos and scaling limits of disordered systems

abstract:
  Inspired by recent work of Alberts, Khanin and Quastel, we formulate general
conditions ensuring that a sequence of multi-linear polynomials of independent
random variables (called polynomial chaos expansions) converges to a limiting
random variable, given by a Wiener chaos expansion over the d-dimensional white
noise. A key ingredient in our approach is a Lindeberg principle for polynomial
chaos expansions, which extends earlier work of Mossel, O'Donnell and
Oleszkiewicz. These results provide a unified framework to study the continuum
and weak disorder scaling limits of statistical mechanics systems that are
disorder relevant, including the disordered pinning model, the (long-range)
directed polymer model in dimension 1+1, and the two-dimensional random field
Ising model. This gives a new perspective in the study of disorder relevance,
and leads to interesting new continuum models that warrant further studies.


title:
Uniaxial versus Biaxial Character of Nematic Equilibria in Three
  Dimensions

abstract:
  We study global minimizers of the Landau-de Gennes (LdG) energy functional
for nematic liquid crystals, on arbitrary three-dimensional simply connected
geometries with topologically non-trivial and physically relevant Dirichlet
boundary conditions. Our results are specific to the low-temperature limit. We
prove (i) that (re-scaled) global LdG minimizers converge uniformly to a
(minimizing) limiting harmonic map, away from the singular set of the limiting
map; (ii) there exist both a point of maximal biaxiality and a nonempty
Lebesgue-null set of uniaxial points near each singular point of the limiting
harmonic map (this improves the recent results of \cite{contreraslamy});
  (iii) estimates for the size of "strongly biaxial" regions in terms of the
reduced temperature $t$. We further show that global LdG minimizers in the
restricted class of uniaxial $\Qvec$-tensors cannot be stable critical points
of the LdG energy for low temperatures.


title:
Topological Analysis of Emerging Bipole Clusters Producing Violent Solar
  Events

abstract:
  During the rising phase of Solar Cycle 24 tremendous activity occurred on the
Sun with fast and compact emergence of magnetic flux leading to bursts of
flares (C to M and even X-class). We investigate the violent events occurring
in the cluster of two active regions (ARs), NOAA numbers 11121 and 11123,
observed in November 2010 with instruments onboard the {\it Solar Dynamics
Observatory} and from Earth. Within one day the total magnetic flux increased
by $70\%$ with the emergence of new groups of bipoles in AR 11123. From all the
events on 11 November, we study, in particular, the ones starting at around
07:16 UT in GOES soft X-ray data and the brightenings preceding them. A
magnetic-field topological analysis indicates the presence of null points,
associated separatrices and quasi-separatrix layers (QSLs) where magnetic
reconnection is prone to occur. The presence of null points is confirmed by a
linear and a non-linear force-free magnetic-field model. Their locations and
general characteristics are similar in both modelling approaches, which
supports their robustness. However, in order to explain the full extension of
the analysed event brightenings, which are not restricted to the photospheric
traces of the null separatrices, we compute the locations of QSLs. Based on
this more complete topological analysis, we propose a scenario to explain the
origin of a low-energy event preceding a filament eruption, which is
accompanied by a two-ribbon flare, and a consecutive confined flare in AR
11123. The results of our topology computation can also explain the locations
of flare ribbons in two other events, one preceding and one following the ones
at 07:16 UT. Finally, this study provides further examples where flare-ribbon
locations can be explained when compared to QSLs and only, partially, when
using separatrices.


title: Geometry of quantum evolution for mixed quantum states

abstract:
  The geometric formulation of quantum mechanics is a very interesting field of
research which has many applications in the emerging field of quantum
computation and quantum information, such as schemes for optimal quantum
computers. In this work we discuss a geometric formulation of mixed quantum
states represented by density operators. Our formulation is based on principal
fiber bundles and purifications of quantum states. In our construction, the
Riemannian metric and symplectic form on the total space are induced from the
real and imaginary parts of the Hilbert-Schmidt Hermitian inner product, and we
define a mechanical connection in terms of a locked inertia tensor and moment
map. We also discuss some applications of our geometric framework.