title:
Least worst regret analysis for decision making under uncertainty, with
  applications to future energy scenarios

abstract:
  Least worst regret (and sometimes minimax) analysis are often used for
decision making whenever it is difficult, or inappropriate, to attach
probabilities to possible future scenarios. We show that, for each of these two
approaches and subject only to the convexity of the cost functions involved, it
is always the case that there exist two "extreme" scenarios whose costs
determine the outcome of the analysis in the sense we make clear. The results
of either analysis are therefore particularly sensitive to the cost functions
associated with these two scenarios, while being largely unaffected by those
associated with the remainder. Great care is therefore required in applications
to identify these scenarios and to consider their reasonableness.
  We also consider the relationship between the outcome of a least worst regret
and a Bayesian analysis, particularly in the case where the regret functions
associated with the scenarios largely differ from each other by shifts in their
arguments, as is the case in many applications.
  We study in detail the problem of determining an appropriate level of
electricity capacity procurement in Great Britain, where decisions must be made
several years in advance, in spite of considerable uncertainty as to which of a
number of future scenarios may occur, and where least worst regret analysis is
currently used as the basis of decision making.


title: Knowledge Distillation for Small-footprint Highway Networks

abstract:
  Deep learning has significantly advanced state-of-the-art of speech
recognition in the past few years. However, compared to conventional Gaussian
mixture acoustic models, neural network models are usually much larger, and are
therefore not very deployable in embedded devices. Previously, we investigated
a compact highway deep neural network (HDNN) for acoustic modelling, which is a
type of depth-gated feedforward neural network. We have shown that HDNN-based
acoustic models can achieve comparable recognition accuracy with much smaller
number of model parameters compared to plain deep neural network (DNN) acoustic
models. In this paper, we push the boundary further by leveraging on the
knowledge distillation technique that is also known as {\it teacher-student}
training, i.e., we train the compact HDNN model with the supervision of a high
accuracy cumbersome model. Furthermore, we also investigate sequence training
and adaptation in the context of teacher-student training. Our experiments were
performed on the AMI meeting speech recognition corpus. With this technique, we
significantly improved the recognition accuracy of the HDNN acoustic model with
less than 0.8 million parameters, and narrowed the gap between this model and
the plain DNN with 30 million parameters.


title:
On the stability of equivariant embedding of compact CR manifolds with
  circle action

abstract:
  We prove the stability of the equivariant embedding of compact strictly
pseudoconvex CR manifolds with transversal CR circle action under circle
invariant perturbations of the CR structures.


title: Theory of Landau level mixing in heavily graded graphene p-n junctions

abstract:
  We demonstrate the use of a quantum transport model to study heavily graded
graphene p-n junctions in the quantum Hall regime. A combination of p-n
interface roughness and delta function disorder potential allows us to compare
experimental results on different devices from the literature. We find that
wide p-n junctions suppress mixing of $n \neq 0$ Landau levels. Our simulations
spatially resolve carrier transport in the device, for the first time,
revealing separation of higher order Landau levels in strongly graded
junctions, which suppresses mixing.


title:
RETURNN: The RWTH Extensible Training framework for Universal Recurrent
  Neural Networks

abstract:
  In this work we release our extensible and easily configurable neural network
training software. It provides a rich set of functional layers with a
particular focus on efficient training of recurrent neural network topologies
on multiple GPUs. The source of the software package is public and freely
available for academic research purposes and can be used as a framework or as a
standalone tool which supports a flexible configuration. The software allows to
train state-of-the-art deep bidirectional long short-term memory (LSTM) models
on both one dimensional data like speech or two dimensional data like
handwritten text and was used to develop successful submission systems in
several evaluation campaigns.


title:
Modeling of microdevices for SAW-based acoustophoresis --- a study of
  boundary conditions

abstract:
  We present a finite-element method modeling of acoustophoretic devices
consisting of a single, long, straight, water-filled microchannel surrounded by
an elastic wall of either borosilicate glass (pyrex) or the elastomer
polydimethylsiloxane (PDMS) and placed on top of a piezoelectric transducer
that actuates the device by surface acoustic waves (SAW). We compare the
resulting acoustic fields in these full solid-fluid models with those obtained
in reduced fluid models comprising of only a water domain with simplified,
approximate boundary conditions representing the surrounding solids. The
reduced models are found to only approximate the acoustically hard pyrex
systems to a limited degree for large wall thicknesses and not at all for the
acoustically soft PDMS systems.


title: Irreducible $p$-modular representations of unramified $U(2,1)$

abstract:
  Let $E/F$ be a unramified quadratic extension of non-archimedean local fields
of odd characteristic $p$, and $G$ be the unramified unitary group $U(2,
1)(E/F)$. For an irreducible smooth representation $\pi$ of $G$ over
$\overline{\mathbf{F}}_p$, with an underlying irreducible smooth representation
$\sigma$ of a maximal compact open subgroup $K$, we prove that $\pi$ admits
eigenvectors for an appropriate Hecke operator $T_\sigma$, and we classify
those $\pi$ with non-zero eigenvalues for $T_\sigma$ by a tree argument; as a
corollary, we show $\pi$ is supersingular if and only if it is supercuspidal.


title:
Superfluidity of a rarefied gas of electron-hole pairs in a bilayer
  system

abstract:
  The conditions of stability of the superfluid phase in double layer systems
with pairing of spatially separated electrons and holes in the low density
limit are studied. The general expression for the collective excitation
spectrum is obtained. It is shown that under increase in the distance $d$
between the layers the minimum emerges in the excitation spectrum. When d
reaches the critical value the superfluid state becomes unstable relative to
the formation of a kind of the Wigner crystal state. The same instability
occurs at fixed d under increase in the density of carries. It is established
that the critical distance and the critical density are related to each other
by the inverse power function. The impact of the impurities on the temperature
of the superfluid transition is investigated. The impact is found weak at the
impurity concentration smaller than the density of the pairs. It is shown that
in the rarefied system the critical temperature T_c = 100 K can be reached.


title:
Polarization forces in the vicinity of nanoparticles in weakly ionized
  plasma

abstract:
  It is shown that the polarization forces in a weakly ionized plasma lead to a
substantial increase in the fluxes of neutral atoms and molecules to the
surface of charged nanoparticles. Thus, the nanoparticles can change thermal
balance due to the acceleration of atoms and molecules in the dipole potential
and subsequent inelastic collisions to the nanoparticles.


title:
Effects of Pore-Scale Disorder on Fluid Displacement in
  Partially-Wettable Porous Media

abstract:
  We present a systematic, quantitative assessment of the impact of pore size
disorder and its interplay with flow rates and wettability on immiscible
displacement of a viscous fluid. Pore-scale simulations and micromodel
experiments show that reducing disorder increases the displacement efficiency
and compactness, minimizing the fluid-fluid interfacial area, through (i)
trapping at low rates and (ii) viscous fingering at high rates. Increasing the
wetting angle suppresses both trapping and fingering, hence reducing the
sensitivity of the displacement to the underlying disorder. A modified
capillary number $\mathrm{Ca^*}$ that includes the impact of disorder $\lambda$
on viscous forces (through pore connectivity) is direct related to $\lambda$,
in par with previous works. Our findings bear important consequences on sweep
efficiency and fluid mixing and reactions, which are key in applications such
as microfluidics to carbon geosequestration, energy recovery, and soil aeration
and remediation.


title: New Strategy to Explore CP Violation with $B^0_s\to K^-K^+$

abstract:
  The $U$-spin symmetry provides a powerful tool to extract the angle $\gamma$
of the Unitarity Triangle and the $B_s^0$-$\bar{B}_s^0$ mixing phase $\phi_s$
from CP violation in the $B^0_s\to K^-K^+$, $B^0_d\to\pi^-\pi^+$ system. LHCb
has obtained first results with uncertainties at the $7^\circ$ level. Due to
$U$-spin-breaking corrections, it will be challenging to reduce the uncertainty
below ${\cal O}(5^\circ)$ at Belle II and the LHCb upgrade. We propose a new
strategy, using $\gamma$ as input and utilizing $B^0_s\to K^-\ell^+\nu_\ell$,
$B^0_d\to \pi^-\ell^+\nu_\ell$ decays, which allows an extraction of $\phi_s$
with a future theoretical precision of up to ${\cal O}(0.5^\circ)$, thereby
matching the experimental prospects. Since $B^0_s\to K^-K^+$ is dominated by
penguin topologies, new sources of CP violation may be revealed.


title: Multipole Expansion in Generalized Electrodynamics

abstract:
  In this article we study some classical aspects of Podolsky Electrodynamics
in the static regime. We develop the multipole expansion for the theory in both
the electrostatic and the magnetostatic cases. We also address the problem of
consistently truncating the infinite series associated with the several kinds
of multipoles, yielding approximations for the static Podolskian
electromagnetic field to any degree of precision required. Moreover, we apply
the general theory of multipole expansion to some specific physical problems.
In those problems we identify the first terms of the series with the monopole,
dipole and quadrupole terms in the generalized theory. We also propose a
situation in which Podolsky theory can be experimentally tested.


title:
Genoautotomy (Genome 'Self-Injury') in Eukaryotic Cells: A Cellular
  Defence Response to Genotoxic Stress

abstract:
  This paper proposes that eukaryotic cells, under severe genotoxic stress, can
commit genoautotomy (genome 'self-injury') that involves cutting and releasing
single-stranded DNA (ssDNA) fragments from double-stranded DNA and leaving
ssDNA gaps in the genome. The ssDNA gaps could be easily and precisely repaired
later. The released ssDNA fragments may play some role in the regulation of
cell cycle progression. Taken together, genoautotomy causes limited nonlethal
DNA damage, but prevents the whole genome from lethal damage, and thus should
be deemed as a eukaryotic cellular defence response to genotoxic stress.


title: Further results on the deficiency of graphs

abstract:
  A \emph{proper $t$-edge-coloring} of a graph $G$ is a mapping $\alpha:
E(G)\rightarrow \{1,\ldots,t\}$ such that all colors are used, and
$\alpha(e)\neq \alpha(e^{\prime})$ for every pair of adjacent edges
$e,e^{\prime}\in E(G)$. If $\alpha $ is a proper edge-coloring of a graph $G$
and $v\in V(G)$, then \emph{the spectrum of a vertex $v$}, denoted by
$S\left(v,\alpha \right)$, is the set of all colors appearing on edges incident
to $v$. \emph{The deficiency of $\alpha$ at vertex $v\in V(G)$}, denoted by
$def(v,\alpha)$, is the minimum number of integers which must be added to
$S\left(v,\alpha \right)$ to form an interval, and \emph{the deficiency
$def\left(G,\alpha\right)$ of a proper edge-coloring $\alpha$ of $G$} is
defined as the sum $\sum_{v\in V(G)}def(v,\alpha)$. \emph{The deficiency of a
graph $G$}, denoted by $def(G)$, is defined as follows:
$def(G)=\min_{\alpha}def\left(G,\alpha\right)$, where minimum is taken over all
possible proper edge-colorings of $G$. For a graph $G$, the smallest and the
largest values of $t$ for which it has a proper $t$-edge-coloring $\alpha$ with
deficiency $def(G,\alpha)=def(G)$ are denoted by $w_{def}(G)$ and $W_{def}(G)$,
respectively. In this paper, we obtain some bounds on $w_{def}(G)$ and
$W_{def}(G)$. In particular, we show that for any $l\in \mathbb{N}$, there
exists a graph $G$ such that $def(G)>0$ and $W_{def}(G)-w_{def}(G)\geq l$. It
is known that for the complete graph $K_{2n+1}$, $def(K_{2n+1})=n$ ($n\in
\mathbb{N}$). Recently, Borowiecka-Olszewska, Drgas-Burchardt and Ha{\l}uszczak
posed the following conjecture on the deficiency of near-complete graphs: if
$n\in \mathbb{N}$, then $def(K_{2n+1}-e)=n-1$. In this paper, we confirm this
conjecture.


title: PicHunt: Social Media Image Retrieval for Improved Law Enforcement

abstract:
  First responders are increasingly using social media to identify and reduce
crime for well-being and safety of the society. Images shared on social media
hurting religious, political, communal and other sentiments of people, often
instigate violence and create law & order situations in society. This results
in the need for first responders to inspect the spread of such images and users
propagating them on social media. In this paper, we present a comparison
between different hand-crafted features and a Convolutional Neural Network
(CNN) model to retrieve similar images, which outperforms state-of-art
hand-crafted features. We propose an Open-Source-Intelligent (OSINT) real-time
image search system, robust to retrieve modified images that allows first
responders to analyze the current spread of images, sentiments floating and
details of users propagating such content. The system also aids officials to
save time of manually analyzing the content by reducing the search space on an
average by 67%.


title:
Embeddings of Weighted Hilbert Spaces and Applications to Multivariate
  and Infinite-Dimensional Integration

abstract:
  We study embeddings and norm estimates for tensor products of weighted
reproducing kernel Hilbert spaces. These results lead to a transfer principle
that is directly applicable to tractability studies of multivariate problems as
integration and approximation, and to their infinite-dimensional counterparts.
In an application we consider weighted tensor product Sobolev spaces of mixed
smoothness of any integer order, equipped with the classical, the anchored, or
the ANOVA norm. Here we derive new results for multivariate and
infinite-dimensional integration.


title:
Phase-sensitive amplification via coherent population oscillations in
  metastable helium at room temperature

abstract:
  We report our experimental results on phase-sensitive amplification (PSA) in
non-degenerate signal-idler configuration using ultra-narrow coherent
population oscillations in metastable helium at room temperature. We achieved a
high PSA gain of nearly 7 with a bandwidth of 200 kHz, by using the system at
resonance in a single-pass scheme. Further, the measured minimum gain is close
to the ideal value, showing that we have a pure PSA. This is also confirmed
from our phase-to-phase transfer curves measurements, illustrating that we have
a nearly perfect squeezer, which is interesting for a variety of applications.


title: Linear Density Perturbations in Multifield Coupled Quintessence

abstract:
  We study the behaviour of linear perturbations in multifield coupled
quintessence models. Using gauge invariant linear cosmological perturbation
theory we provide the full set of governing equations for this class of models,
and solve the system numerically. We apply the numerical code to generate
growth functions for various examples, and compare these both to the standard
$\Lambda$CDM model and to current and future observational bounds. Finally, we
examine the applicability of the "small scale approximation", often used to
calculate growth functions in quintessence models, in light of upcoming
experiments such as SKA and Euclid. We find the deviation of the full equation
results for large k modes from the approximation exceeds the experimental
uncertainty for these future surveys. The numerical code, PYESSENCE, written in
Python will be publicly available.


title: Vortex knots in tangled quantum eigenfunctions

abstract:
  Tangles of string typically become knotted, from macroscopic twine down to
long-chain macromolecules such as DNA. Here we demonstrate that knotting also
occurs in quantum wavefunctions, where the tangled filaments are vortices
(nodal lines/phase singularities). The probability that a vortex loop is
knotted is found to increase with its length, and a wide gamut of knots from
standard tabulations occur. The results follow from computer simulations of
random superpositions of degenerate eigenstates of three simple quantum
systems: a cube with periodic boundaries, the isotropic 3-dimensional harmonic
oscillator and the 3-sphere. In the latter two cases, vortex knots occur
frequently, even in random eigenfunctions at relatively low energy, and are
constrained by the spatial symmetries of the modes. The results suggest that
knotted vortex structures are generic in complex 3-dimensional wave systems,
establishing a topological commonality between wave chaos, polymers and
turbulent Bose-Einstein condensates.


title:
PYESSENCE - Generalised Coupled Quintessence Linear Perturbation Python
  Code - User Guide

abstract:
  This paper is a guide to the installation and use of the Python package
PYESSENCE. PYESSENCE is designed to evolve linear perturbations to Coupled
Quintessence models with a arbitrary number of cold dark matter (CDM) fluids
and dark energy (DE) scalar fields as dictated by a given model. The equations
are sufficiently general to allow for more exotic dark matter with a non-zero
equation of state. Several example uses are included in order to demonstrate
typical functionality to the potential user. PYESSENCE is released under an
open source modified BSD license and is available on Bitbucket.


title:
Modeling Spatial and Temporal Cues for Multi-label Facial Action Unit
  Detection

abstract:
  Facial action units (AUs) are essential to decode human facial expressions.
Researchers have focused on training AU detectors with a variety of features
and classifiers. However, several issues remain. These are spatial
representation, temporal modeling, and AU correlation. Unlike most studies that
tackle these issues separately, we propose a hybrid network architecture to
jointly address them. Specifically, spatial representations are extracted by a
Convolutional Neural Network (CNN), which, as analyzed in this paper, is able
to reduce person-specific biases caused by hand-crafted features (eg, SIFT and
Gabor). To model temporal dependencies, Long Short-Term Memory (LSTMs) are
stacked on top of these representations, regardless of the lengths of input
videos. The outputs of CNNs and LSTMs are further aggregated into a fusion
network to produce per-frame predictions of 12 AUs. Our network naturally
addresses the three issues, and leads to superior performance compared to
existing methods that consider these issues independently. Extensive
experiments were conducted on two large spontaneous datasets, GFT and BP4D,
containing more than 400,000 frames coded with 12 AUs. On both datasets, we
report significant improvement over a standard multi-label CNN and
feature-based state-of-the-art. Finally, we provide visualization of the
learned AU models, which, to our best knowledge, reveal how machines see facial
AUs for the first time.


title: A time-work uncertainty relation in quantum systems

abstract:
  In quantum systems, a plausible definition of work is based on two energy
measurement scheme. Considering that energy change of quantum system obeys a
time-energy uncertainty relation, it shall be interesting to see whether such
type of work as well obeys an analogous uncertainty relation. In this note I
argue that this relation indeed exists for closed quantum systems and open
quantum systems, which the latter are assumed to be weakly coupled with their
environments.


title:
Analysis of Multi-Hop Outdoor 60 GHz Wireless Networks with Full-Duplex
  Buffered Relays

abstract:
  The abundance of unlicensed spectrum in the 60 GHz band makes it an
attractive alternative for future wireless communication systems. Such systems
are expected to provide data transmission rates in the order of multi-gigabits
per second in order to satisfy the ever-increasing demand for high rate data
communication. Unfortunately, 60 GHz radio is subject to severe path loss which
limits its usability for long-range outdoor communication. In this work, we
propose a multi-hop 60 GHz wireless network for outdoor communication where
multiple full-duplex buffered relays are used to extend the communication range
while providing end-to-end performance guarantees to the traffic traversing the
network. We provide a cumulative service process characterization for the 60
GHz outdoor propagation channel with self-interference in terms of the moment
generating function (MGF) of its channel capacity. We then use this
characterization to compute probabilistic upper bounds on the overall network
performance, i.e., total backlog and end-to-end delay. Furthermore, we study
the effect of self-interference on the network performance and propose an
optimal power allocation scheme to mitigate its impact in order to enhance
network performance. Finally, we investigate the relation between relay density
and network performance under a total power budget constraint. We show that
increasing relay density may have adverse effects on network performance unless
self-interference can be kept sufficiently small.


title:
Classifying dense (co)resolving subcategories of exact categories via
  Grothendieck groups

abstract:
  Classification problems of subcategories have been deeply considered so far.
In this paper, we discuss classifying dense (co)resolving subcategories of
exact categories via their Grothendieck groups. This study is motivated by the
classification of dense triangulated subcategories of triangulated categories
due to Thomason.


title: Sgluons in the same-sign lepton searches

abstract:
  In this work I present the interpretation of the ATLAS search of same-sign
lepton production in association with $b$-jets in the context of the 4-top
quark signal from sgluon decays. I show that using just 3.2/fb data sample from
Run 2 the exclusion limit is already competitive with the Run 1 one. Public
data allow to exclude sgluons with masses up to 0.95 TeV. Prospects for the
total Run 2 integrated luminosity of 100/fb are briefly discussed.


title:
Threading Through Macrocycles Enhances the Performance of Carbon
  Nanotubes as Polymer Fillers

abstract:
  In this work we study the reinforcement of polymers by mechanically
interlocked derivatives of single-walled carbon nanotubes (SWNTs). We compare
the mechanical properties of fibers made of polymers and of composites with
pristine single-walled carbon nanotubes (SWNTs), mechanically interlocked
derivatives of SWNTs (MINTs) and the corresponding supramolecular models.
Improvements of both Young's modulus and tensile strength of up to 200 % were
observed for the polystyrene-MINTs samples with an optimized loading of just
0.01 wt.%, while the supramolecular models with identical chemical composition
and loading showed negligible or even detrimental influence. This behavior is
found for three different types of SWNTs and two types of macrocycles.
Molecular dynamics simulations show that the polymer adopts an elongated
conformation parallel to the SWNT when interacting with MINT fillers,
irrespective of the macrocycle chemical nature, whereas a more globular
structure is taken upon facing with either pristine SWNTs or supramolecular
models. The MINT composite architecture thus leads to a more efficient
exploitation of the axial properties of the SWNTs and of the polymer chain at
the interface, in agreement with experimental results. Our findings demonstrate
that the mechanical bond imparts distinctive advantageous properties to SWNT
derivatives as polymer fillers.


title: Scaling the Kalman filter for large-scale traffic estimation

abstract:
  This work introduces a scalable filtering algorithm for multi-agent traffic
estimation. Large-scale networks are spatially partitioned into overlapping
road sections. The traffic dynamics of each section is given by the switching
mode model (SMM) using a conservation principle, and the traffic state in each
section is estimated by a local agent. In the proposed filter, a consensus term
is applied to promote inter-agent agreement on overlapping sections. The new
filter, termed a (spatially) distributed local Kalman consensus filter (DLKCF),
is shown to maintain globally asymptotically stable (GAS) mean error dynamics
when all sections switch among observable modes. When a section is
unobservable, we show that the mean estimate of each state variable in the
section is ultimately bounded, which is achieved by exploring the interaction
between the properties of the traffic model and the measurement feedback of the
filter. Based on the above results, the boundedness of the mean estimation
error of the DLKCF under switching sequences with observable and unobservable
modes is established to address the overall performance of the filter.
Numerical experiments show the ability of the DLKCF to promote consensus,
increase estimation accuracy compared to a local filter, and reduce the
computational load compared to a centralized approach.


title:
The mass of planet GJ676A b from ground-based astrometry: A planetary
  system with two mature gas giants suitable for direct imaging

abstract:
  GJ676A is an M0 dwarf hosting both gas-giant and super-Earth-type planets
discovered with radial-velocity measurements. Using FORS2/VLT, we obtained
position measurements of the star in the plane of the sky that tightly
constrain its astrometric reflex motion caused by the super-Jupiter planet `b`
in a 1052-day orbit. This allows us to determine the mass of this planet to
$M_\mathrm{b} = 6.7^{+1.8}_{-1.5}\,M_\mathrm{J}$, which is $\sim$40 \% higher
than the minimum mass inferred from the radial-velocity orbit. Using new HARPS
radial-velocity measurements, we improve upon the orbital parameters of the
inner low-mass planets `d` and `e` and we determine the orbital period of the
outer giant planet `c` to $P_\mathrm{c}=7340$ days under the assumption of a
circular orbit. The preliminary minimum mass of planet `c` is $M_\mathrm{c}
\sin i = 6.8\,M_\mathrm{J}$ with an upper limit of $\sim$$39\,M_\mathrm{J}$
that we set using NACO/VLT high-contrast imaging. We also determine precise
parallaxes and relative proper motions for both GJ676A and its wide M3
companion GJ676B. Despite the probably mature age of the system, the masses and
projected separations ($\sim$0.1" -- 0.4") of planets `b` and `c` make them
promising targets for direct imaging with future instruments in space and on
extremely large telescopes. In particular, we estimate that GJ676A b and GJ676A
c are promising targets for directly detecting their reflected light with the
WFIRST space mission. Our study demonstrates the synergy of radial-velocity and
astrometric surveys that is necessary to identify the best targets for such a
mission.


title: The PADME experiment

abstract:
  The PADME experiment, hosted at the Laboratori Nazionali di Frascati, will
search for a Dark Photon that decays in invisible channels with a mass up to
$23.7\,\mbox{MeV}$ and coupling constant down to $10^{-3}$.


title:
Community Detection Algorithm Combining Stochastic Block Model and
  Attribute Data Clustering

abstract:
  We propose a new algorithm to detect the community structure in a network
that utilizes both the network structure and vertex attribute data. Suppose we
have the network structure together with the vertex attribute data, that is,
the information assigned to each vertex associated with the community to which
it belongs. The problem addressed this paper is the detection of the community
structure from the information of both the network structure and the vertex
attribute data. Our approach is based on the Bayesian approach that models the
posterior probability distribution of the community labels. The detection of
the community structure in our method is achieved by using belief propagation
and an EM algorithm. We numerically verified the performance of our method
using computer-generated networks and real-world networks.


title: Registration of Volumetric Prostate Scans using Curvature Flow

abstract:
  Radiological imaging of the prostate is becoming more popular among
researchers and clinicians in searching for diseases, primarily cancer. Scans
might be acquired with different equipment or at different times for prognosis
monitoring, with patient movement between scans, resulting in multiple datasets
that need to be registered. For these cases, we introduce a method for
volumetric registration using curvature flow. Multiple prostate datasets are
mapped to canonical solid spheres, which are in turn aligned and registered
through the use of identified landmarks on or within the gland. Theoretical
proof and experimental results show that our method produces homeomorphisms
with feature constraints. We provide thorough validation of our method by
registering prostate scans of the same patient in different orientations, from
different days and using different modes of MRI. Our method also provides the
foundation for a general group-wise registration using a standard reference,
defined on the complex plane, for any input. In the present context, this can
be used for registering as many scans as needed for a single patient or
different patients on the basis of age, weight or even malignant and
non-malignant attributes to study the differences in general population. Though
we present this technique with a specific application to the prostate, it is
generally applicable for volumetric registration problems.


title: Notes on the A_inf-cohomology of Integral p-adic Hodge theory

abstract:
  We present a detailed overview of the construction of the A_inf-cohomology
theory from the preprint "Integral p-adic Hodge theory", joint with B. Bhatt
and P. Scholze. We focus particularly on the p-adic analogue of the Cartier
isomorphism via relative de Rham--Witt complexes.


title:
Stacking faults and the {\gamma}-surface on {1-101} pyramidal planes in
  {\alpha}-titanium

abstract:
  Using first principles methods we calculated the entire {\gamma}-surface of
the first order pyramidal planes in {\alpha}-titanium. Slip on these planes
involving dislocations with c + a dislocations is one means by which
{\alpha}-titanium polycrystals may supplement slip on prism planes with a-type
Burgers vectors to maintain ductility. We find two stable intrinsic stacking
faults with relatively small energies. We show that dissociation of c + a
dislocations into two dislocations with Burgers vectors (c + a)/2 is not
possible in {\alpha}-titanium because there is no stable stacking fault at (c +
a)/2. Instead we propose a possible dissociation of a c + a dislocation into
three partial dislocations separated by the two intrinsic faults we have
identified.


title:
Quasi locality of the GGE in interacting-to-free quenches in
  relativistic field theories

abstract:
  We study the quench dynamics in continuous relativistic quantum field theory,
more specifically the locality properties of the large time stationary state.
After a quantum quench in a one-dimensional integrable model, the expectation
values of local observables are expected to relax to a Generalized Gibbs
Ensemble (GGE), constructed out of the conserved charges of the model.
Quenching to a free bosonic theory, it has been shown that the system indeed
relaxes to a GGE described by the momentum mode occupation numbers. We first
address the question whether the latter can be written directly in terms of
local charges and we find that, in contrast to the lattice case, this is not
possible in continuous field theories. We then investigate the less stringent
requirement of the existence of a sequence of truncated local GGEs that
converges to the correct steady state, in the sense of the expectation values
of the local observables. While we show that such a sequence indeed exists, in
order to unequivocally determine the so-defined GGE, we find that information
about the expectation value of the recently discovered quasi-local charges is
in the end necessary, the latter being the suitable generalization of the local
charges while passing from the lattice to the continuum. Lastly, we study the
locality properties of the GGE and show that the latter is completely
determined by the knowledge of the expectation value of a countable set of
suitably defined quasi-local charges.


title:
Media Query Processing For The Internet-of-Things: Coupling Of Device
  Energy Consumption And Cloud Infrastructure Billing

abstract:
  Audio/visual recognition and retrieval applications have recently garnered
significant attention within Internet-of-Things (IoT) oriented services, given
that video cameras and audio processing chipsets are now ubiquitous even in
low-end embedded systems. In the most typical scenario for such services, each
device extracts audio/visual features and compacts them into feature
descriptors, which comprise media queries. These queries are uploaded to a
remote cloud computing service that performs content matching for
classification or retrieval applications. Two of the most crucial aspects for
such services are: (i) controlling the device energy consumption when using the
service; (ii) reducing the billing cost incurred from the cloud infrastructure
provider. In this paper we derive analytic conditions for the optimal coupling
between the device energy consumption and the incurred cloud infrastructure
billing. Our framework encapsulates: the energy consumption to produce and
transmit audio/visual queries, the billing rates of the cloud infrastructure,
the number of devices concurrently connected to the same cloud server, {the
query volume constraint of each cluster of devices,} and the statistics of the
query data production volume per device. Our analytic results are validated via
a deployment with: (i) the device side comprising compact image descriptors
(queries) computed on Beaglebone Linux embedded platforms and transmitted to
Amazon Web Services (AWS) Simple Storage Service; (ii) the cloud side carrying
out image similarity detection via AWS Elastic Compute Cloud (EC2) instances,
with the AWS Auto Scaling being used to control the number of instances
according to the demand.


title: Nonnoetherian coordinate rings with unique maximal depictions

abstract:
  A depiction of a nonnoetherian integral domain $R$ is a special coordinate
ring that provides a framework for describing the geometry of $R$. We show that
if $R$ is noetherian in codimension 1, then $R$ has a unique maximal depiction
$T$. In this case, the geometric dimensions of the points of
$\operatorname{Spec}R$ may be computed directly from $T$. If in addition $R$
has a normal depiction $S$, then $S$ is the unique maximal depiction of $R$.


title: Rogue waves in nonlocal media

abstract:
  The generation of rogue waves is investigated via a nonlocal nonlinear
Schrodinger (NLS) equation. In this system, modulation instability is
suppressed and is usually expected that rogue wave formation would also be
limited. On the contrary, a parameter regime is identified where the
instability is suppressed but nevertheless the number and amplitude of the
rogue events increase, as compared to the standard NLS (which is a limit of the
nonlocal system). Furthermore, the nature of these waves is investigated; while
no analytical solutions are known to model these events, numerically it is
shown that they differ significantly from either the rational (Peregrine) or
soliton solution of the limiting NLS equation. As such, these findings may also
help in rogue wave realization experimentally in these media.


title:
Non-resonant Fredholm alternative and anti-maximum principle for the
  fractional $p-$Laplacian

abstract:
  In this paper we extend two nowadays classical results to a nonlinear
Dirichlet problem to equations involving the fractional $p-$Laplacian. The
first result is a existence in a non-resonant range more specific between the
first and second eigenvalue of the fractional $p-$Laplacian. The second result
is the anti-maximum principle for the fractional $p-$Laplacian.


title: Efficient Segmental Cascades for Speech Recognition

abstract:
  Discriminative segmental models offer a way to incorporate flexible feature
functions into speech recognition. However, their appeal has been limited by
their computational requirements, due to the large number of possible segments
to consider. Multi-pass cascades of segmental models introduce features of
increasing complexity in different passes, where in each pass a segmental model
rescores lattices produced by a previous (simpler) segmental model. In this
paper, we explore several ways of making segmental cascades efficient and
practical: reducing the feature set in the first pass, frame subsampling, and
various pruning approaches. In experiments on phonetic recognition, we find
that with a combination of such techniques, it is possible to maintain
competitive performance while greatly reducing decoding, pruning, and training
time.


title: Stem Cells: The Good, the Bad and the Ugly

abstract:
  Cancer stem cells are controlled by developmental networks that are often
topologically indistinguishable from normal, healthy stem cells. The question
is why cancer stem cells can be both phenotypically distinct and have
morphological effects so different from normal stem cells. The difference
between cancer stem cells and normal stem cells lies not in differences their
network architecture, but rather in the spatial-temporal locality of their
activation in the genome and the resulting expression in the body. The
metastatic potential cancer stem cells is not based primarily on their network
divergence from normal stem cells, but on non-network based genetic changes
that enable the evolution of gene-based phenotypic properties of the cell that
permit its escape and travel to other parts of the body. Stem cell network
theory allows the precise prediction of stem cell behavioral dynamics and a
mathematical description of stem cell proliferation for both normal and cancer
stem cells. It indicates that the best therapeutic approach is to tackle the
highest order stem cells first, otherwise spontaneous remission of so called
cured cancers will always be a danger. Stem cell networks point to a pathway to
new methods to diagnose and cure not only stem cell cancers but cancers
generally.


title: The real nonnegative inverse eigenvalue problem is NP-hard

abstract:
  A list of complex numbers is realizable if it is the spectrum of a
nonnegative matrix. In 1949 Suleimanova posed the nonnegative inverse
eigenvalue problem (NIEP): the problem of determining which lists of complex
numbers are realizable. The version for reals of the NIEP (RNIEP) asks for
realizable lists of real numbers. In the literature there are many sufficient
conditions or criteria for lists of real numbers to be realizable. We will
present an unified account of these criteria. Then we will see that the
decision problem associated to the RNIEP is NP-hard and we will study the
complexity for the decision problems associated to known criteria.


title: Smooth magnetogenesis

abstract:
  In the Ratra scenario of inflationary magnetogenesis, the kinematic coupling
between the photon and the inflaton undergoes a nonanalytical jump at the end
of inflation. Using smooth interpolating analytical forms of the coupling
function, we show that such unphysical jump does not invalidate the main
prediction of the model, which still represents a viable mechanism for
explaining cosmic magnetization. Nevertheless, there is a spurious result
associated with the nonanaliticity of the coupling, to wit, the prediction that
the spectrum of created photons has a power-law decay in the ultraviolet
regime. This issue is discussed using both semiclassical approximation and
smooth coupling functions.


title: FPn properties of generalized Houghton groups

abstract:
  This Thesis presents a 2-dimensional generalization of Houghtons' groups H_n.
H_n is defined to be the group of all permutations p of a disjoint union of
copies of the natural numbers N, with the property that each copy of N contains
a cofinite subset on which p restricts to a translation. Our group G(n) is
defined to be the group of all permutations p of a disjoint union of quadrants
(i.e., copies of NxN) with the property that each quadrant contains a
subquadrant on which p is a translation, while p restricted to the remaining
set is piecewise isometric on a cofinite disjoint union of rays (each isometric
to N). Based on K.S. Brown's treatment of the Houghton group case it is shown
that G(n) is of type FP(n-1); in fact, that G(n) contains a normal subgroup N
with G(n)/N = Z^(n-1) which is of type FP(n-1) and not FPn.


title:
Semi-empirical Modeling of the Photosphere, Chromosphere, Transition
  Region, and Corona of the M-dwarf Host Star GJ 832

abstract:
  Stellar radiation from X-rays to the visible provides the energy that
controls the photochemistry and mass loss from exoplanet atmospheres. The
important extreme ultraviolet (EUV) region (10--91.2~nm) is inaccessible and
should be computed from a reliable stellar model. It is essential to understand
the formation regions and physical processes responsible for the various
stellar emission features in order to predict how the spectral energy
distribution varies with age and activity levels. We compute a state-of-the-art
semi-empirical atmospheric model and the emergent high-resolution synthetic
spectrum of the moderately active M2~V star GJ~832 as the first of a series of
models for stars with different activity levels. Using non-LTE radiative
transfer techniques and including many molecular lines, we construct a
one-dimensional simple model for the physical structure of the star's
chromosphere, chromosphere-corona transition region, and corona. The
synthesized spectrum for this model fits the continuum and lines across the UV
to optical spectrum. Particular emphasis is given to the emission lines at
wavelengths shorter than 300~nm observed with {\em HST}, which have important
effects on the photochemistry in the exoplanet atmospheres. The FUV line ratios
indicate that the transition region of GJ~832 is more biased to hotter material
than that of the quiet Sun. The excellent agreement of our computed EUV
luminosity with that obtained by two other techniques indicates that our model
predicts reliable EUV emission from GJ~832. We find that unobserved EUV flux of
GJ~832, which heats the outer atmospheres of exoplanets and drives their mass
loss, is comparable to the active Sun.


title:
High-Order Adaptive Gegenbauer Integral Spectral Element Method for
  Solving Nonlinear Optimal Control Problems

abstract:
  In this work, we propose an adaptive spectral element algorithm for solving
nonlinear optimal control problems. The method employs orthogonal collocation
at the shifted Gegenbauer-Gauss points combined with very accurate and stable
numerical quadratures to fully discretize the multiple-phase integral form of
the optimal control problem. The proposed algorithm relies on exploiting the
underlying smoothness properties of the solutions for computing approximate
solutions efficiently. In particular, the method brackets discontinuities and
"points of nonsmoothness" through a novel local adaptive algorithm, which
achieves a desired accuracy on the discrete dynamical system equations by
adjusting both the mesh size and the degree of the approximating polynomials. A
rigorous error analysis of the developed numerical quadratures is presented.
Finally, the efficiency of the proposed method is demonstrated on three test
examples from the open literature.


title: Multimodal Brain Visualization

abstract:
  Current connectivity diagrams of human brain image data are either overly
complex or overly simplistic. In this work we introduce simple yet accurate
interactive visual representations of multiple brain image structures and the
connectivity among them. We map cortical surfaces extracted from human brain
magnetic resonance imaging (MRI) data onto 2D surfaces that preserve shape
(angle), extent (area), and spatial (neighborhood) information for 2D (circular
disk) and 3D (spherical) mapping, split these surfaces into separate patches,
and cluster functional and diffusion tractography MRI connections between pairs
of these patches. The resulting visualizations are easier to compute on and
more visually intuitive to interact with than the original data, and facilitate
simultaneous exploration of multiple data sets, modalities, and statistical
maps.


title:
Ultra-coherent nanomechanical resonators via soft clamping and
  dissipation dilution

abstract:
  The small mass and high coherence of nanomechanical resonators render them
the ultimate force probe, with applications ranging from biosensing and
magnetic resonance force microscopy, to quantum optomechanics. A notorious
challenge in these experiments is thermomechanical noise related to dissipation
through internal or external loss channels. Here, we introduce a novel approach
to defining nanomechanical modes, which simultaneously provides strong spatial
confinement, full isolation from the substrate, and dilution of the resonator
material's intrinsic dissipation by five orders of magnitude. It is based on a
phononic bandgap structure that localises the mode, without imposing the
boundary conditions of a rigid clamp. The reduced curvature in the highly
tensioned silicon nitride resonator enables mechanical $Q>10^{8}$ at $ 1
\,\mathrm{MHz}$, yielding the highest mechanical $Qf$-products
($>10^{14}\,\mathrm{Hz}$) yet reported at room temperature. The corresponding
coherence times approach those of optically trapped dielectric particles.
Extrapolation to $4{.}2$ Kelvin predicts $\sim$quanta/ms heating rates, similar
to trapped ions.


title: Evolutionary forces in language change

abstract:
  Languages and genes are both transmitted from generation to generation, with
opportunity for differential reproduction and survivorship of forms. Here we
apply a rigorous inference framework, drawn from population genetics, to
distinguish between two broad mechanisms of language change: drift and
selection. Drift is change that results from stochasticity in transmission and
it may occur in the absence of any intrinsic difference between linguistic
forms; whereas selection is truly an evolutionary force arising from intrinsic
differences -- for example, when one form is preferred by members of the
population. Using large corpora of parsed texts spanning the 12th century to
the 21st century, we analyze three examples of grammatical changes in English:
the regularization of past-tense verbs, the rise of the periphrastic `do', and
syntactic variation in verbal negation. We show that we can reject stochastic
drift in favor of a selective force driving some of these language changes, but
not others. The strength of drift depends on a word's frequency, and so drift
provides an alternative explanation for why some words are more prone to change
than others. Our results suggest an important role for stochasticity in
language change, and they provide a null model against which selective theories
of language evolution must be compared.


title: Characterizations of ordered operator spaces

abstract:
  We demonstrate new abstract characterizations for unital and non-unital
operator spaces. We characterize unital operator spaces in terms of the cone of
accretive operators (operators whose real part is positive). Defining the gauge
of an operator $T \in B(H)$ to be $\|Re(T)_+\|$, we demonstrate an abstract
characterization of operator spaces up to complete gauge-isometry. Both of
these characterizations preserve the structure of the self-adjoint, positive,
and accretive operators, as well as the operator norm. We show that an operator
space with a given matrix ordering of positive or accretive cones can be
represented completely isometrically and completely order isomorphically if and
only if each positive cone is normal, in the sense that $x \leq y \leq z$
implies that $\|y\| \leq \max(\|x\|,\|z\|)$ at each matrix level. This is
achieved by showing that normal matrix ordered operator spaces are induced by
gauges. We show that inducing gauges are not unique in general. Finally, we
show that completely positive completely contractive linear maps on non-unital
operator spaces extend to any containing operator system if and only if the
operator space is induced by a unique gauge.


title: Massive 3d Abelian gauge theories and electric-magnetic duality

abstract:
  We study a model of massive photons with a parity invariant and non-local
mass term. We identify a discrete symmetry of the classical equations of motion
and show that this symmetry can be thought of as an electric-magnetic duality
valid only in the presence of a non-zero photon mass. We explore this duality
and discuss some features of the theory. We define notions of electric and
magnetic charge that can be computed in any spatial domain as a volume integral
of a density. These integrals can be transformed into integrals on the
boundary. For instance, the electric charge is given by the sum of the electric
flux through the boundary of the domain and a line integral of the dual gauge
field along that same boundary. We show that electric and magnetic charge is
quantized $q_mq_e = 2\pi n m_\gamma/e^2$, where $e$ is the coupling constant
and $m_\gamma$ is the mass of the photon. Classical field configurations
associated with external electric and magnetic charges as well as the classical
forces between electric and magnetic charges are computed.


title:
A Unified Paradigm of Organized Complexity and Semantic Information
  Theory

abstract:
  One of the most fundamental problems in science is to define {\it
quantitatively} the complexity of organized matters, i.e., {\it organized
complexity}. Although many measures have been proposed toward this aim in
previous decades, there is no agreed upon definition. This paper presents a new
quantitative definition of organized complexity. This definition {\it
simultaneously} captures the three major features of complexity: computational
(similar to logical depth), descriptional (similar to the Kolmogorov complexity
and effective complexity) and distributional (similar to statistical
complexity). In addition, the proposed definition is computable and can measure
both probabilistic and deterministic forms of objects in a unified manner. The
proposed definition is based on circuits rather than Turing machines and
$\epsilon$-machines. We give several criteria required for organized complexity
measures and show that the proposed definition satisfies all of them for the
first time. We then apply this quantitative definition to formulate a {\it
semantic information theory}. We present the first formal definition of a {\it
semantic information amount}, which is the core concept of the semantic
information theory, that is based only on concretely defined notions. Previous
semantic information theories defined this amount under some a priori
information which is not concretely specified. We then unveil several
fundamental properties in the semantic information theory, e.g., a semantic
source coding theorem, semantic channel coding theorem, and effectiveness
coding theorem. Although the semantic information theory has a long history of
research going back more than six decades, there has been no study on its
relation to organized complexity. This paper offers the first unified paradigm
of organized complexity and semantic information theory.


title:
Split scores: a tool to quantify phylogenetic signal in genome-scale
  data

abstract:
  Detecting variation in the evolutionary process along chromosomes is
increasingly important as whole-genome data becomes more widely available. For
example, factors such as incomplete lineage sorting, horizontal gene transfer,
and chromosomal inversion are expected to result in changes in the underlying
gene trees along a chromosome, while changes in selective pressure and
mutational rates for different genomic regions may lead to shifts in the
underlying mutational process. We propose the split score as a general method
for quantifying support for a particular phylogenetic relationship within a
genomic data set. Because the split score is based on algebraic properties of a
matrix of site pattern frequencies, it can be rapidly computed, even for data
sets that are large in the number of taxa and/or in the length of the
alignment, providing an advantage over other methods (e.g., maximum likelihood)
that are often used to assess such support. Using simulation we explore the
properties of the split score, including its dependence on sequence length,
branch length, size of a split and its ability to detect true splits in the
underlying tree. Using a sliding window analysis, we show that split scores can
be used to detect changes in the underlying evolutionary process for
genome-scale data from primates, mosquitoes, and viruses in a computationally
efficient manner. Computation of the split score has been implemented in the
software package SplitSup.


title: Investigating the Circumstellar Disk of the Be Shell Star 48 Librae

abstract:
  A global disk oscillation implemented in the viscous decretion disk (VDD)
model has been used to reproduce most of the observed properties of the well
known Be star $\zeta$ Tau. 48 Librae shares several similarities with $\zeta$
Tau -- they are both early-type Be stars, they display shell characteristics in
their spectra, and they exhibit cyclic $V/R$ variations -- but has some marked
differences as well, such as a much denser and more extended disk, a much
longer $V/R$ cycle, and the absence of the so-called triple-peak features. We
aim to reproduce the photometric, polarimetric, and spectroscopic observables
of 48 Librae with a self-consistent model, and to test the global oscillation
scenario for this target. Our calculations are carried out with the
three-dimensional NLTE radiative transfer code HDUST. We employ a rotationally
deformed, gravity-darkened central star, surrounded by a disk whose unperturbed
state is given by the VDD model. A two-dimensional global oscillation code is
then used to calculate the disk perturbation, and superimpose it on the
unperturbed disk. A very good, self-consistent fit to the time-averaged
properties of the disk is obtained with the VDD. The calculated perturbation
has a period $P = 12$ yr, which agrees with the observed period, and the
behaviour of the $V/R$ cycle is well reproduced by the perturbed model. The
perturbed model improves the fit to the photometric data and reproduces some
features of the observed spectroscopic data. Some suggestions to improve the
synthesized spectroscopy in a future work are given.


title:
Distributed or Monolithic? A Computational Architecture Decision
  Framework

abstract:
  Distributed architectures have become ubiquitous in many complex technical
and socio-technical systems because of their role in improving uncertainty
management, accommodating multiple stakeholders, and increasing scalability and
evolvability. This departure from monolithic architectures provides a system
with more flexibility and robustness in response to uncertainties that it may
confront during its lifetime. Distributed architecture does not provide
benefits only, as it can increase cost and complexity of the system and result
in potential instabilities. The mechanisms behind this trade-off, however, are
analogous to those of the widely-studied transition from integrated to modular
architectures. In this paper, we use a conceptual decision framework that
unifies modularity and distributed architecture on a five-stage systems
architecture spectrum. We add an extensive computational layer to the framework
and explain how this can enhance decision making about the level of modularity
of the architecture. We then apply it to a simplified demonstration of the
Defense Advanced Research Projects Agency (DARPA) fractionated satellite
program. Through simulation, we calculate the net value that is gained (or
lost) by migrating from a monolithic architecture to a distributed architecture
and show how this value changes as a function of uncertainties in the
environment and various system parameters. Additionally, we use Value at Risk
as a measure for the risk of losing the value of distributed architecture,
given its inherent uncertainty.


title: Blocking Collapsed Gibbs Sampler for Latent Dirichlet Allocation Models

abstract:
  The latent Dirichlet allocation (LDA) model is a widely-used latent variable
model in machine learning for text analysis. Inference for this model typically
involves a single-site collapsed Gibbs sampling step for latent variables
associated with observations. The efficiency of the sampling is critical to the
success of the model in practical large scale applications. In this article, we
introduce a blocking scheme to the collapsed Gibbs sampler for the LDA model
which can, with a theoretical guarantee, improve chain mixing efficiency. We
develop two procedures, an O(K)-step backward simulation and an O(log K)-step
nested simulation, to directly sample the latent variables within each block.
We demonstrate that the blocking scheme achieves substantial improvements in
chain mixing compared to the state of the art single-site collapsed Gibbs
sampler. We also show that when the number of topics is over hundreds, the
nested-simulation blocking scheme can achieve a significant reduction in
computation time compared to the single-site sampler.


title:
Co-Production of Cement and Carbon Nanotubes with a Carbon Negative
  Footprint

abstract:
  C2CNT (Carbon dioxide to carbon nanotube) cement plants have been introduced
and analyzed which provide a significant economic incentive to eliminate the
massive CO2 greenhouse gas emissions of current plants and serves as a template
for carbon mitigation in other industrial manufacturing processes. Rather than
regarding CO2 as a costly pollutant, this is accomplished by treating CO2 as a
feedstock resource to generate valuable products (carbon nanotubes). The
exhaust from partial and full oxy-fuel cement plant configurations are coupled
to the inlet of a C2CNT chamber in which CO2 is transformed by electrolysis in
a molten carbonate electrolyte at a steel cathode and a nickel anode. In this
high yield 4e- per CO2 process, the CO2 is transformed into carbon nanotubes at
the cathode, and pure oxygen at the anode that is looped back in improving the
cement line energy efficiency and rate of production. A partial oxy-fuel
process looping the pure oxygen back in through the plant calcinator has been
compared to a full oxy-fuel process in which it is looped back in through the
plant kiln. The second provides the advantage of easier retrofit, while the
first maximizes efficiency by minimizing the volume of gas throughput
(eliminating N2 from air). An upper limit to the electrical cost to drive C2CNT
electrolysis is USD70 based on Texas wind power costs, but will be lower with
fuel expenses when oxy-fuel plant energy improvements are taken account. The
current value of a ton of carbon nanotubes is substantially in excess of a ton
of cement. Hence a C2CNT cement plant consumes USD50 of electricity, emits no
CO2, and produces USD100 of cement and USD60,000 of carbon nanotubes per ton of
CO2 avoided. As the cement product ages, CO2 is spontaneously absorbed. This is
a powerful economic incentive, rather than economic cost, to mitigate climate
change through a carbon negative process.


title:
Diffusion of particles in simple fluids: A joint theory of kinetics and
  hydrodynamics

abstract:
  The particle diffusion in a fluid is a classical topic that dates back to
more than one century ago. However, a full solution to this issue still lacks.
In this work the velocity autocorrelation function and the diffusion constant
are derived analytically, and the hydrodynamics effect on the particle
diffusion is analyzed in detail. Unlike previous studies, the ring-collision
effect is exhaustively considered in our treatment, and the hydrodynamics
approach is extended to the whole time range. Large scale molecular dynamics
simulations for the hard-disk fluid show that our analytical results are valid
up to the density close to the crystallization point.


title:
The bootstrap, covariance matrices and PCA in moderate and
  high-dimensions

abstract:
  We consider the properties of the bootstrap as a tool for inference
concerning the eigenvalues of a sample covariance matrix computed from an
$n\times p$ data matrix $X$. We focus on the modern framework where $p/n$ is
not close to 0 but remains bounded as $n$ and $p$ tend to infinity.
  Through a mix of numerical and theoretical considerations, we show that the
bootstrap is not in general a reliable inferential tool in the setting we
consider. However, in the case where the population covariance matrix is
well-approximated by a finite rank matrix, the bootstrap performs as it does in
finite dimension.


title: Differential calculus on $\mathbb{Z}^n_2$-supermanifolds

abstract:
  The concept of $\Zn$-supermanifold has been recently proposed as a natural
generalization of classical ($\Zs$-graded) supergeometry, allowing for more
complicated commutativity constraints. Here we continue the study of
$\Zn$-supergeometry by developing the foundations of differential calculus on
$\Zn$-supermanifolds.


title: Elementary approach to the Hartogs extension theorem

abstract:
  In this paper we present a proof of Hartogs' extension theorem, following T.
Sobieszek's paper from 2003. Hartogs' theorem provides a large class of domains
where holomorphic functions have analytic continuation to larger domains, and
is "a several complex variables theorem" in nature because its conclusion is
false in the complex plane. Sobieszek's proof is quite remarkable because he
uses, stated in his paper without proofs, only higher-dimensional identity
principle for holomorphic functions and Cauchy's integral formula for compact
sets. We proved this two theorems here, making this exposition self-contained.
The only background required is an undergraduate course in real and complex
analysis and in point-set topology.


title: Rationality does not specialize among terminal fourfolds

abstract:
  We show that rationality does not specialize in flat projective families of
complex fourfolds with terminal singularities. This answers a question of
Totaro, who established the analogous result in all dimensions greater than 4.


title: Upper Bounds for the Number of Solutions to Spatially Coupled Sudokus

abstract:
  Based on combinatorics, we evaluate the upper bounds for the number of
solutions to spatially coupled Sudokus, which are popular logic puzzles.


title: Bergman-H\"older Functions, Area Integral Means and Extremal Problems

abstract:
  We study certain weighted area integral means of analytic functions in the
unit disc. We relate the growth of these means to the property of being mean
H\"older continuous with respect to the Bergman space norm. In contrast with
earlier work, we use the second iterated difference quotient instead of the
first. We then give applications to Bergman space extremal problems.


title:
Scaling limit of the uniform infinite half-plane quadrangulation in the
  Gromov-Hausdorff-Prokhorov-uniform topology

abstract:
  We prove that the uniform infinite half-plane quadrangulation (UIHPQ), with
either general or simple boundary, equipped with its graph distance, its
natural area measure, and the curve which traces its boundary, converges in the
scaling limit to the Brownian half-plane. The topology of convergence is given
by the so-called Gromov-Hausdorff-Prokhorov-uniform (GHPU) metric on
curve-decorated metric measure spaces, which is a generalization of the
Gromov-Hausdorff metric whereby two such spaces $(X_1, d_1 , \mu_1,\eta_1)$ and
$(X_2, d_2 , \mu_2,\eta_2)$ are close if they can be isometrically embedded
into a common metric space in such a way that the spaces $X_1$ and $X_2$ are
close in the Hausdorff distance, the measures $\mu_1$ and $\mu_2$ are close in
the Prokhorov distance, and the curves $\eta_1$ and $\eta_2$ are close in the
uniform distance.


title:
Metric gluing of Brownian and $\sqrt{8/3}$-Liouville quantum gravity
  surfaces

abstract:
  In a recent series of works, Miller and Sheffield constructed a metric on
$\sqrt{8/3}$-Liouville quantum gravity (LQG) under which $\sqrt{8/3}$-LQG
surfaces (e.g., the LQG sphere, wedge, cone, and disk) are isometric to their
Brownian surface counterparts (e.g., the Brownian map, half-plane, plane, and
disk).
  We identify the metric gluings of certain collections of independent
$\sqrt{8/3}$-LQG surfaces with boundaries identified together according to LQG
length along their boundaries. Our results imply in particular that the metric
gluing of two independent instances of the Brownian half-plane along their
positive boundaries is isometric to a certain LQG wedge decorated by an
independent chordal SLE$_{8/3}$ curve. If one identifies the two sides of the
boundary of a single Brownian half-plane, one obtains a certain LQG cone
decorated by an independent whole-plane SLE$_{8/3}$. If one identifies the
entire boundaries of two Brownian half-planes, one obtains a different LQG cone
and the interface between them is a two-sided variant of whole-plane
SLE$_{8/3}$.
  Combined with another work of the authors, the present work identifies the
scaling limit of self-avoiding walk on random quadrangulations with SLE$_{8/3}$
on $\sqrt{8/3}$-LQG.


title:
Convergence of the self-avoiding walk on random quadrangulations to
  SLE$_{8/3}$ on $\sqrt{8/3}$-Liouville quantum gravity

abstract:
  We prove that a uniform infinite quadrangulation of the half-plane decorated
by a self-avoiding walk (SAW) converges in the scaling limit to the metric
gluing of two independent Brownian half-planes identified along their positive
boundary rays. Combined with other work of the authors, this implies the
convergence of the SAW on a random quadrangulation to SLE$_{8/3}$ on a certain
$\sqrt{8/3}$-Liouville quantum gravity surface. The topology of convergence is
the local Gromov-Hausdorff-Prokhorov-uniform topology, the natural
generalization of the local Gromov-Hausdorff topology to curve-decorated metric
measure spaces. We also prove analogous scaling limit results for uniform
infinite quadrangulations of the whole plane decorated by either a one-sided or
two-sided SAW. Our proof uses only the peeling procedure for random
quadrangulations and some basic properties of the Brownian half-plane, so can
be read without any knowledge of SLE or LQG.


title:
Measurement of the ionization produced by sub-keV silicon nuclear
  recoils in a CCD dark matter detector

abstract:
  We report a measurement of the ionization efficiency of silicon nuclei
recoiling with sub-keV kinetic energy in the bulk silicon of a charge-coupled
device (CCD). Nuclear recoils are produced by low-energy neutrons ($<$24 keV)
from a $^{124}$Sb-$^{9}$Be photoneutron source, and their ionization signal is
measured down to 60 eV electron equivalent. This energy range, previously
unexplored, is relevant for the detection of low-mass dark matter particles.
The measured efficiency is found to deviate from the extrapolation to low
energies of the Lindhard model. This measurement also demonstrates the
sensitivity to nuclear recoils of CCDs employed by DAMIC, a dark matter direct
detection experiment located in the SNOLAB underground laboratory.

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


title:
Fredholm determinant and Nekrasov sum representations of isomonodromic
  tau functions

abstract:
  We derive Fredholm determinant representation for isomonodromic tau functions
of Fuchsian systems with $n$ regular singular points on the Riemann sphere and
generic monodromy in $\mathrm{GL}(N,\mathbb C)$. The corresponding operator
acts in the direct sum of $N(n-3)$ copies of $L^2(S^1)$. Its kernel has a block
integrable form and is expressed in terms of fundamental solutions of $n-2$
elementary 3-point Fuchsian systems whose monodromy is determined by monodromy
of the relevant $n$-point system via a decomposition of the punctured sphere
into pairs of pants. For $N=2$ these building blocks have hypergeometric
representations, the kernel becomes completely explicit and has Cauchy type. In
this case Fredholm determinant expansion yields multivariate series
representation for the tau function of the Garnier system, obtained earlier via
its identification with Fourier transform of Liouville conformal block (or a
dual Nekrasov-Okounkov partition function). Further specialization to $n=4$
gives a series representation of the general solution to Painlev\'e VI
equation.


title: On semitopological bicyclic extensions of linearly ordered groups

abstract:
  For a linearly ordered group $G$ let us define a subset $A\subseteq G$ to be
a \emph{shift-set} if for any $x,y,z\in A$ with $y < x$ we get $x\cdot
y^{-1}\cdot z\in A$. We describe the natural partial order and solutions of
equations on the semigroup $\mathscr{B}(A)$ of shifts of positive cones of $A$.
We study topologizations of the semigroup $\mathscr{B}(A)$. In particular, we
show that for an arbitrary countable linearly ordered group $G$ and a non-empty
shift-set $A$ of $G$ every Baire shift-continuous $T_1$-topology $\tau$ on
$\mathscr{B}(A)$ is discrete. Also we prove that for an arbitrary linearly
non-densely ordered group $G$ and a non-empty shift-set $A$ of $G$, every
shift-continuous Hausdorff topology $\tau$ on the semigroup $\mathscr{B}(A)$ is
discrete, and hence $\left(\mathscr{B}(A),\tau\right)$ is a discrete subspace
of any Hausdorff semitopological semigroup which contains $\mathscr{B}(A)$ as a
subsemigroup.


title: Morin singularities of coframes and frames

abstract:
  Inspired by the properties of an $n$-frame of gradients $(\nabla f_1, \ldots,
\nabla f_n)$ of a Morin map $f:M\rightarrow\mathbb{R}^n$, with $\dim M\geq n$,
we introduce the notion of Morin singularities in the context of singular
$n$-coframes and singular $n$-frames. We also study the singularities of
generic 1-forms associated to a Morin $n$-coframe, in order to generalize a
result of T. Fukuda [4, Theorem 1], which establishes a modulo 2 congruence
between the Euler characteristic of a compact manifold $M$ and the Euler
characteristics of the singular sets of a Morin map defined on $M$, to the case
of Morin $n$-coframes and Morin $n$-frames.


title: The Frobenius theorem for $\mathbb{Z}^n_2$-supermanifolds

abstract:
  We continue the development of $\mathbb{Z}^n_2$-supergeometry, a natural
generalization of classical ($\mathbb{Z}_2$-graded) supergeometry, by proving
the Frobenius theorem for integrable distributions on differentiable
$\mathbb{Z}^n_2$-supermanifolds. Both the local and global versions of the
theorem are addressed.


title: Variable Radio Emission from the Young Stellar Host of a Hot Jupiter

abstract:
  We report the discovery of variable radio emission associated with the T
Tauri star, V830 Tau, which was recently shown to host a hot Jupiter companion.
Very Large Array observations at a frequency of 6 GHz reveal a detection on 01
May 2011 with a flux density $919 \pm 26\ \mu$Jy, along with non-detections in
two other epochs at $<66$ and $<150\ \mu$Jy. Additionally, Very Long Baseline
Array observations include one detection and one non-detection at comparable
sensitivity, demonstrating that the emission is nonthermal in origin. The
emission is consistent with the gyro-synchrotron or synchrotron mechanism from
a region with a magnetic field ${\stackrel{\scriptstyle >}{\scriptstyle \sim}}
30$ G, and is likely driven by an energetic event such as magnetic reconnection
that accelerated electrons. With the limited data we have, we are not able to
place any constraint on the relationship between the radio emission and the
rotational or orbital properties of V830 Tau. This is the first detection of
radio emission from a non-degenerate star known to host an exoplanet.


title:
Precise radial velocities of giant stars IX. HD 59686 Ab: a massive
  circumstellar planet orbiting a giant star in a ~13.6 au eccentric binary
  system

abstract:
  Context: For over 12 yr, we have carried out a precise radial velocity survey
of a sample of 373 G and K giant stars using the Hamilton \'Echelle
Spectrograph at Lick Observatory. There are, among others, a number of multiple
planetary systems in our sample as well as several planetary candidates in
stellar binaries. Aims: We aim at detecting and characterizing
substellar+stellar companions to the giant star HD 59686 A (HR 2877, HIP
36616). Methods: We obtained high precision radial velocity (RV) measurements
of the star HD 59686 A. By fitting a Keplerian model to the periodic changes in
the RVs, we can assess the nature of companions in the system. In order to
discriminate between RV variations due to non-radial pulsation or stellar spots
we used infrared RVs taken with the CRIRES spectrograph at the Very Large
Telescope. Additionally, to further characterize the system, we obtain
high-resolution images with LMIRCam at the Large Binocular Telescope. Results:
We report the likely discovery of a giant planet with a mass of $m_{p}~\sin
i=6.92_{-0.24}^{+0.18}~M_{Jup}$ orbiting at $a_{p}=1.0860_{-0.0007}^{+0.0006}$
au from the giant star HD 59686 A. Besides the planetary signal, we discover an
eccentric ($e_{B}=0.729_{-0.003}^{+0.004}$) binary companion with a mass of
$m_{B}~\sin i=0.5296_{-0.0008}^{+0.0011}~M_{Sun}$ orbiting at a semi-major axis
of just $a_{B}=13.56_{-0.14}^{+0.18}$ au. Conclusions: The existence of the
planet HD 59686 Ab in a tight eccentric binary system severely challenges
standard giant planet formation theories and requires substantial improvements
to such theories in tight binaries. Otherwise, alternative planet formation
scenarios such as second generation planets or dynamical interactions in an
early phase of the system's lifetime should be seriously considered in order to
better understand the origin of this enigmatic planet.


title:
Spatio-temporal Correlations in the Manna Model in one, three and five
  dimensions

abstract:
  Although the paradigm of criticality is centred around spatial correlations
and their anomalous scaling, not many studies of Self-Organised Criticality
(SOC) focus on spatial correlations. Often, integrated observables, such as
avalanche size and duration, are used, not least as to avoid complications due
to the unavoidable lack of translational invariance. The present work is a
survey of spatio-temporal correlation functions in the Manna Model of SOC,
measured numerically in detail in d=1,3 and 5 dimensions and compared to
theoretical results, in particular relating them to "integrated" observables
such as avalanche size and duration scaling, that measure them indirectly.
Contrary to the notion held by some of SOC models organising into a critical
state by re-arranging their spatial structure avalanche by avalanche, which may
be expected to result in large, non-trivial, system-spanning spatial
correlations in the quiescent state (between avalanches), correlations of
inactive particles in the quiescent state have a small amplitude that does not
increase with the system size, although they display (noisy) power law scaling
over a range linear in the system size. Self-organisation, however, does take
place as the (one-point) density of inactive particles organises into a
particular profile that is asymptotically independent of the driving location,
also demonstrated analytically in one dimension. Activity and its correlations,
on the other hand, display non-trivial long-ranged spatio-temporal scaling with
exponents that can be related to established results, in particular avalanche
size and duration exponents. The correlation length and amplitude are set by
the system size (confirmed analytically for some observables), as expected in
systems displaying finite size scaling. In one dimension, we find some
surprising inconsistencies of the dynamical exponent. A (spatially extended)
mean ...


title:
Event simulation based on three-fluid hydrodynamics for collisions at
  energies available at the Dubna Nuclotron-based Ion Collider Facility and at
  the Facility for Antiproton and Ion Research in Darmstadt

abstract:
  We present a new event generator based on the three-fluid hydrodynamics
approach for the early stage of the collision, followed by a particlization at
the hydrodynamic decoupling surface to join to a microscopic transport model,
UrQMD, to account for hadronic final state interactions. We present first
results for nuclear collisions of the FAIR/NICA energy scan program (Au+Au
collisions, $\sqrt{s_{NN}}=4-11$ GeV). We address the directed flow of protons
and pions as well as the proton rapidity distribution for two model EoS, one
with a first order phase transition the other with a crossover type softening
at high densities. The new simulation program has the unique feature that it
can describe a hadron-to-quark matter transition which proceeds in the baryon
stopping regime that is not accessible to previous simulation programs designed
for higher energies.


title:
Extremely Small Sizes for Faint z~2-8 Galaxies in the Hubble Frontier
  Fields: A Key Input For Establishing their Volume Density and UV Emissivity

abstract:
  We provide the first observational constraints on the sizes of the faintest
galaxies lensed by the Hubble Frontier Fields (HFF) clusters. Ionizing
radiation from faint galaxies likely drives cosmic reionization, and the HFF
initiative provides a key opportunity to find such galaxies. Yet, we cannot
really assess their ionizing emissivity without a robust measurement of their
sizes, since this is key to quantifying both their prevalence and the faint-end
slope to the UV luminosity function. Here we provide the first such size
constraints with 2 new techniques. The first utilizes the fact that the
detectability of highly-magnified galaxies as a function of shear is very
dependent on a galaxy's size. Only the most compact galaxies will remain
detectable in regions of high shear (vs. a larger detectable size range for low
shear), a phenomenon we carefully quantify using simulations. Remarkably,
however, no correlation is found between the surface density of faint galaxies
and the predicted shear, using 87 faint high-magnification mu>10 z~2-8 galaxies
seen behind the first 4 HFF clusters. This can only be the case if such faint
(~-15 mag) galaxies have significantly smaller sizes than luminous galaxies. We
constrain their half-light radii to be <~30 mas (<160-240 pc). As a 2nd size
probe, we rotate and stack 26 faint high-magnification sources along the major
shear axis. Less elongation is found than even for objects with an intrinsic
half-light radius of 10 mas. Together these results indicate that extremely
faint z~2-8 galaxies have near point-source profiles in the HFF dataset
(half-light radii conservatively <30 mas and likely 5-10 mas). These results
suggest smaller completeness corrections and hence much lower volume densities
for faint z~2-8 galaxies and shallower faint-end slopes than have been derived
in many recent studies (by factors of ~2-3 and by dalpha>~0.1-0.3).


title: Cosmic Initial Conditions for a Habitable Universe

abstract:
  Within the framework of an eternal inflationary scenario, a natural question
regarding the production of eternal bubbles is the essential condition requires
to have a universe capable of generating life. In either an open or a closed
universe, we find an anthropic lower bound on the amount of e-folding in the
order of $60$ for the inflationary epoch, which results in the formation of
large-scale structures in both linear and non-linear regimes. We extend the
question of the initial condition of the universe to the sufficient condition
in which we have enough initial dark matter and baryonic matter asymmetry in
the early universe for the formation of galactic halos, stars, planets and
consequently life. We show that the probability of a habitable universe is
proportional to the asymmetry of dark matter and baryonic matter, while the
cosmic budget of baryonic matter is limited by the astrophysical constrains.


title:
Tilted resonators in a triangular elastic lattice: chirality, Bloch
  waves and negative refraction

abstract:
  We consider a vibrating triangular mass-truss lattice whose unit cell
contains a resonator of a triangular shape. The resonators are connected to the
triangular lattice by trusses. Each resonator is tilted, i.e. it is rotated
with respect to the triangular lattice's unit cell through an angle
$\vartheta_0$. This geometrical parameter is responsible for the emergence of a
resonant mode in the Bloch spectrum for elastic waves and strongly affects the
dispersive properties of the lattice. Additionally, the tilting angle
$\vartheta_0$ triggers the opening of a band gap at a Dirac-like point. We
provide a physical interpretation of these phenomena and discuss the dynamical
implications on elastic Bloch waves. The dispersion properties are used to
design a structured interface containing tilted resonators which exhibit
negative refraction and focussing, as in a "flat elastic lens".


title:
Strong Evidence for the Density-wave Theory of Spiral Structure in Disk
  Galaxies

abstract:
  The density-wave theory of galactic spiral-arm structure makes a striking
prediction that the pitch angle of spiral arms should vary with the wavelength
of the galaxy's image. The reason is that stars are born in the density wave
but move out of it as they age. They move ahead of the density wave inside the
co-rotation radius, and fall behind outside of it, resulting in a tighter pitch
angle at wavelengths that image stars (optical and near-infrared) than those
that are associated with star formation (far-infrared and ultraviolet). In this
study we combined large sample size with wide range of wavelengths, from the
ultraviolet to the infrared to investigate this issue. For each galaxy we used
an optical wavelength image (B-band: 445 nm) and images from the Spitzer Space
Telescope at two infrared wavelengths (infrared: 3.6 and 8.0 {\mu}m) and we
measured the pitch angle with the 2DFFT and Spirality codes. We find that the
B-band and 3.6 {\mu}m images have smaller pitch angles than the infrared 8.0
{\mu}m image in all cases, in agreement with the prediction of density-wave
theory. We also used images in the ultraviolet from Galaxy Evolution Explorer,
whose pitch angles agreed with the measurements made at 8 {\mu}m.


title: Long-term stream evolution in tidal disruption events

abstract:
  A large number of tidal disruption event (TDE) candidates have been observed
recently, often differing in their observational features. Two classes appear
to stand out: X-ray and optical TDEs, the latter featuring lower effective
temperatures and luminosities. These differences can be explained if the
radiation detected from the two categories of events originates from different
locations. In practice, this location is set by the evolution of the debris
stream around the black hole and by the energy dissipation associated with it.
In this paper, we build an analytical model for the stream evolution, whose
dynamics is determined by both magnetic stresses and shocks. Without magnetic
stresses, the stream always circularizes. The ratio of the circularization
timescale to the initial stream period is $t_{\rm ev}/t_{\rm min} = 8.3 (M_{\rm
h}/10^6 M_{\odot})^{-5/3} \beta^{-3}$, where $M_{\rm h}$ is the black hole mass
and $\beta$ is the penetration factor. If magnetic stresses are strong, they
can lead to the stream ballistic accretion. The boundary between
circularization and ballistic accretion corresponds to a critical magnetic
stresses efficiency $v_{\rm A}/v_{\rm c} \approx 10^{-1}$, largely independent
of $M_{\rm h}$ and $\beta$. However, the main effect of magnetic stresses is to
accelerate the stream evolution by strengthening self-crossing shocks.
Ballistic accretion therefore necessarily occurs on the stream dynamical
timescale. The shock luminosity associated to energy dissipation is
sub-Eddington but decays as $t^{-5/3}$ only for a slow stream evolution.
Finally, we find that the stream thickness rapidly increases if the stream is
unable to cool completely efficiently. A likely outcome is its fast evolution
into a thick torus, or even an envelope completely surrounding the black hole.


title: The mass distribution and gravitational potential of the Milky Way

abstract:
  We present mass models of the Milky Way created to fit observational
constraints and to be consistent with expectations from theoretical modelling.
The method used to create these models is that demonstrated in McMillan (2011),
and we improve on those models by adding gas discs to the potential,
considering the effects of allowing the inner slope of the halo density profile
to vary, and including new observations of maser sources in the Milky Way
amongst the new constraints. We provide a best fitting model, as well as
estimates of the properties of the Milky Way. Under the assumptions in our main
model, we find that the Sun is $R_0 = (8.20\pm0.09)\,\mathrm{kpc}$ from the
Galactic Centre, with the circular speed at the Sun being $v_0 =
(232.8\pm3.0)\,\mathrm{km}\,\mathrm{s}^{-1}$; that the Galaxy has a total
stellar mass of $(54.3\pm5.7)\times10^9\,{\rm M}_\odot$, a total virial mass of
$(1.30 \pm 0.30)\times10^{12}\,{\rm M}_\odot$ and a local dark-matter density
of $0.38\pm0.04\,\mathrm{GeV\,cm}^{-3}$, where the quoted uncertainties are
statistical. These values are sensitive to our choice of priors and
constraints. We investigate systematic uncertainties, which in some cases may
be larger. For example, if we weaken our prior on $R_0$, we find it to be
$(7.97\pm0.15)\,\mathrm{kpc}$ and that
$v_0=(226.8\pm4.2)\,\mathrm{km}\,\mathrm{s}^{-1}$. We find that most of these
properties, including the local dark-matter density, are remarkably insensitive
to the assumed power-law density slope at the centre of the dark-matter halo.
We find that it is unlikely that the local standard of rest differs
significantly from that found under assumptions of axisymmetry. We have made
code to compute the force from our potential, and to integrate orbits within
it, publicly available.


title:
Metallicity dependence of turbulent pressure and macroturbulence in
  stellar envelopes

abstract:
  Macroturbulence, introduced as a fudge to reproduce the width and shape of
stellar absorption lines, reflects gas motions in stellar atmospheres. While in
cool stars, it is thought to be caused by convection zones immediately beneath
the stellar surface, the origin of macroturbulence in hot stars is still under
discussion. Recent works established a correlation between the
turbulent-to-total pressure ratio inside the envelope of stellar models and the
macroturbulent velocities observed in corresponding Galactic stars. To probe
this connection further, we evaluated the turbulent pressure that arises in the
envelope convective zones of stellar models in the mass range 1-125 Msun based
on the mixing-length theory and computed for metallicities of the Large and
Small Magellanic Cloud. We find that the turbulent pressure contributions in
models with these metallicities located in the hot high-luminosity part of the
Hertzsprung-Russel (HR) diagram is lower than in similar models with solar
metallicity, whereas the turbulent pressure in low-metallicity models
populating the cool part of the HR-diagram is not reduced. Based on our models,
we find that the currently available observations of hot massive stars in the
Magellanic Clouds appear to support a connection between macroturbulence and
the turbulent pressure in stellar envelopes. Multidimensional simulations of
sub-surface convection zones and a larger number of high-quality observations
are necessary to test this idea more rigorously.


title:
Chronos and Kairos: Mosfire Observations of Post-Starburst Galaxies in
  z~1 Clusters and Groups

abstract:
  In this study we present the exploration of $\sim$500 spectroscopically
confirmed galaxies in and around two large scale structures at $z\sim1$ drawn
from the ORELSE survey. A sub-sample of these galaxies ($\sim$150) were
targeted for the initial phases of a near-infrared MOSFIRE spectroscopic
campaign investigating the differences in selections of galaxies which had
recently ended a burst of star formation or had rapidly quenched (i.e.,
post-starburst or K+A galaxies). Selection with MOSFIRE resulted in a
post-starburst sample more than double that selected by traditional $z\sim1$
(observed-frame optical) methods even after the removal of the relatively large
fraction of dusty starburst galaxies selected through traditional methods.
While the traditional post-starburst fraction increased with increased global
density, the MOSFIRE-selected post-starburst fraction was found to be constant
in field, group, and cluster environments. However, this fraction relative to
the number of galaxies with ongoing star formation was observed to elevate in
the cluster environment. Post-starbursts selected with MOSFIRE were
predominantly found to exhibit moderately strong [OII] emission originating
from activity other than star formation. Such galaxies, termed K+A with
ImposteR [OII]-derived Star formation (KAIROS) galaxies, were found to be
considerably younger than traditionally-selected post-starbursts and likely
undergoing some form of feedback absent or diminished in traditional
post-starbursts. A comparison between the environments of the two types of
post-starbursts suggests a picture in which the evolution of a post-starburst
galaxy is considerably different in cluster environments than in the more
rarefied environments of a group or the field.


title: The Molecular Baryon Cycle of M82

abstract:
  Baryons cycle into galaxies from the inter-galactic medium, are converted
into stars, and a fraction of the baryons are ejected out of galaxies by
stellar feedback. Here we present new high resolution (3.9"; 68 pc) CO(2-1) and
CO(3-2) images that probe these three stages of the baryon cycle in the nearby
starburst M 82. We combine these new observations with previous CO(1-0) and [Fe
II] images to study the physical conditions within the molecular gas. Using a
Bayesian analysis and the radiative transfer code RADEX, we model molecular
Hydrogen temperatures and densities, as well as CO column densities. Besides
the disc, we concentrate on two regions within the galaxy: an expanding
super-bubble and the base of a molecular streamer. Shock diagnostics,
kinematics, and optical extinction suggest that the streamer is an inflowing
filament, with a molecular gas mass inflow rate of 3.5 M$_\odot$ yr$^{-1}$. We
measure the molecular gas mass outflow rate of the expanding super-bubble to be
17 M$_\odot$ yr$^{-1}$, 5 times higher than the inferred inflow rate, and 1.3
times the star formation rate of the galaxy. The high mass outflow rate and
large star formation rate will deplete the galaxy of molecular gas within eight
million years, unless there are additional sources of molecular gas.


title: Effective Field Theory with Two Higgs Doublets

abstract:
  In this article we extend the effective field theory framework describing new
physics effects to the case where the underlying low-energy theory is a
Two-Higgs-Doublet model. We derive a complete set of independent operators up
to dimension six assuming a $Z_2$-invariant CP-conserving Higgs potential. The
effects on Higgs and gauge boson masses, mixing angles in the Higgs sector as
well as couplings to fermions and gauge bosons are computed. At variance with
the case of a single Higgs doublet, we find that pair production of SM-like
Higgses, arising through dimension-six operators, is not fixed by
fermion-fermion-Higgs couplings and can therefore be sizable.


title:
Effective theory and emergent $SU(2)$ symmetry in the flat bands of
  attractive Hubbard models

abstract:
  In a partially filled flat Bloch band electrons do not have a well defined
Fermi surface and hence the low-energy theory is not a Fermi liquid.
Neverethless, under the influence of an attractive interaction, a
superconductor well described by the Bardeen-Cooper-Schrieffer (BCS) wave
function can arise. Here we study the low-energy effective Hamiltonian of a
generic Hubbard model with a flat band. We obtain an effective Hamiltonian for
the flat band physics by eliminating higher lying bands via perturbative
Schrieffer-Wolff transformation. At first order in the interaction energy we
recover the usual procedure of projecting the interaction term onto the flat
band Wannier functions. We show that the BCS wave function is the exact ground
state of the projected interaction Hamiltonian and that the compressibility is
diverging as a consequence of an emergent $SU(2)$ symmetry. This symmetry is
broken by second order interband transitions resulting in a finite
compressibility, which we illustrate for a one-dimensional ladder with two
perfectly flat bands. These results motivate a further approximation leading to
an effective ferromagnetic Heisenberg model. The gauge-invariant result for the
superfluid weight of a flat band can be obtained from the ferromagnetic
Heisenberg model only if the maximally localized Wannier functions in the
Marzari-Vanderbilt sense are used. Finally, we prove an important inequality $D
\geq \mathcal{W}^2$ between the Drude weight $D$ and the winding number
$\mathcal{W}$, which guarantees ballistic transport for topologically
nontrivial flat bands in one dimension.

categories: cond-mat.str-el cond-mat.quant-gas cond-mat.supr-con quant-ph


title: Resolving gluon fusion loops at current and future hadron colliders

abstract:
  Inclusive Higgs measurements at the LHC have limited resolution on the gluon
fusion loops, being unable to distinguish the long-distance contributions
mediated by the top quark from possible short-distance new physics effects.
Using an Effective Field Theory (EFT) approach we compare several proposed
methods to lift this degeneracy, including $t\bar{t}h$ and boosted, off-shell
and double Higgs production, and perform detailed projections to the
High-Luminosity LHC and a future hadron collider. In addition, we revisit
off-shell Higgs production. Firstly, we point out its sensitivity to
modifications of the top-$Z$ couplings, and by means of a general analysis we
show that the reach is comparable to that of tree-level processes such as
$t\bar{t}Z$ production. Implications for composite Higgs models are also
discussed. Secondly, we assess the regime of validity of the EFT, performing an
explicit comparison for a simple extension of the Standard Model containing one
vector-like quark.


title:
M Dwarf Activity in the Pan-STARRS 1 Medium-Deep Survey: First Catalog
  and Rotation Periods

abstract:
  We report on an ongoing project to investigate activity in the M dwarf
stellar population observed by the Pan-STARRS 1 Medium Deep Survey (PS1-MDS).
Using a custom-built pipeline, we refine an initial sample of $\approx$ 4
million sources in PS1-MDS to a sample of 184,148 candidate cool stars using
color cuts. Motivated by the well-known relationship between rotation and
stellar activity, we use a multi-band periodogram analysis and visual vetting
to identify 271 sources that are likely rotating M dwarfs. We derive a new set
of polynomials relating M dwarf PS1 colors to fundamental stellar parameters
and use them to estimate the masses, distances, effective temperatures, and
bolometric luminosities of our sample. We present a catalog containing these
values, our measured rotation periods, and cross-matches to other surveys. Our
final sample spans periods of $\lesssim$1-130 days in stars with estimated
effective temperatures of $\approx$ 2700-4000 K. Twenty-two of our sources have
X-ray cross-matches, and they are found to be relatively X-ray bright as would
be expected from selection effects. Our data set provides evidence that
Kepler-based searches have not been sensitive to very slowly-rotating stars
($P_{\rm rot} \gtrsim 70$ d), implying that the observed emergence of very slow
rotators in studies of low-mass stars may be a systematic effect. We also see a
lack of low-amplitude ($<$2%) variability in objects with intermediate (10-40
d) rotation periods, which, considered in conjunction with other observational
results, may be a signpost of a loss of magnetic complexity associated with a
phase of rapid spin-down in intermediate-age M dwarfs. This work represents
just a first step in exploring stellar variability in data from the PS1-MDS
and, in the farther future, LSST.


title: On the spin excitation energy of the nucleon in the Skyrme model

abstract:
  In the Skyrme model of nucleons and nuclei, the spin excitation energy of the
nucleon is traditionally calculated by a fit of the rigid rotor quantization of
spin/isospin of the fundamental Skyrmion (the hedgehog) to the masses of the
nucleon and the Delta resonance. The resulting, quite large spin excitation
energy of the nucleon of about $ 73\, \mbox{MeV}$ is, however, rather difficult
to reconcile with the small binding energies of physical nuclei, among other
problems. Here we argue that a more reliable value for the spin excitation
energy of the nucleon, compatible with many physical constraints, is about $
16\, \mbox{MeV}$. The fit of the rigid rotor to the Delta, on the other hand,
is problematic in any case, because it implies the use of a nonrelativistic
method for a highly relativistic system.