title:
Accurate and efficient numerical calculation of stable densities via
  optimized quadrature and asymptotics

abstract:
  Stable distributions are an important class of infinitely-divisible
probability distributions, of which two special cases are the Cauchy
distribution and the normal distribution. Aside from a few special cases, the
density function for stable distributions has no known analytic form, and is
expressible only through the variate's characteristic function or other
integral forms. In this paper we present numerical schemes for evaluating the
density function for stable distributions, its gradient, and distribution
function in various parameter regimes of interest, some of which had no
pre-existing efficient method for their computation. The novel evaluation
schemes consist of optimized generalized Gaussian quadrature rules for integral
representations of the density function, complemented by various asymptotic
expansions near various values of the shape and argument parameters. We report
several numerical examples illustrating the efficiency of our methods. The
resulting code has been made available online.


title: The higher twisted index theorem for foliations

abstract:
  Given a gerbe $L$, on the holonomy groupoid $\mathcal G$ of the foliation
$(M, \mathcal F)$, whose pull-back to $M$ is torsion, we construct a Connes
$\Phi$-map from the twisted Dupont-Sullivan bicomplex of $\mathcal G$ to the
cyclic complex of the $L$-projective leafwise smoothing operators on $(M,
\mathcal F)$. Our construction allows to couple the $K$-theory analytic indices
of $L$-projective leafwise elliptic operators with the twisted cohomology of
$B\mathcal G$ producing scalar higher invariants. Finally by adapting the
Bismut-Quillen superconnection approach, we compute these higher twisted
indices as integrals over the ambiant manifold of the expected twisted
characteristic classes.


title:
Generating strong squeezing in the dispersive regime of the quantum Rabi
  model

abstract:
  We present a protocol to generate a large degree of squeezing of a boson
(light) field mode strongly coupled to a two-level system in the dispersive
regime. Our protocol exploits the strong dispersive coupling to introduce a
time dependent frequency change of the boson field. With an appropriately timed
sequence of sudden frequency changes, the quantum noise fluctuations in one
quadrature of the field can be reduced well below the standard quantum limit,
with a correspondingly increased uncertainty in the orthogonal quadrature. Even
in the presence of realistic noise and imperfections, the protocol should be
capable of generating substantial squeezing with present experimental
capabilities.


title: On constructing purely affine theories with matter

abstract:
  We explore ways to obtain the very existence of a space-time metric from an
action principle that does not refer to it a priori. Although there are reasons
to believe that only a non-local theory can viably achieve this goal, we
investigate here local theories that start with Schroedinger's purely affine
theory [21], where he gave reasons to set the metric proportional to the Ricci
curvature aposteriori. When we leave the context of unified field theory, and
we couple the non-gravitational matter using some weak equivalence principle,
we can show that the propagation of shock waves does not define a lightcone
when the purely affine theory is local and avoids the explicit use of the Ricci
tensor in realizing the weak equivalence principle. When the Ricci tensor is
substituted for the metric, the equations seem to have only a very limited set
of solutions. This backs the conviction that viable purely affine theories have
to be non-local.


title: Probing the Higgs self coupling via single Higgs production at the LHC

abstract:
  We propose a method to determine the trilinear Higgs self coupling that is
alternative to the direct measurement of Higgs pair production total cross
sections and differential distributions. The method relies on the effects that
electroweak loops featuring an anomalous trilinear coupling would imprint on
single Higgs production at the LHC. We first calculate these contributions to
all the phenomenologically relevant Higgs production ($gg{\rm F}$, VBF, $WH$,
$ZH$, $t\bar tH$) and decay ($\gamma \gamma$, $WW^{*}/ZZ^{*}\to 4f$, $b\bar b$,
$\tau \tau$) modes at the LHC and then estimate the sensitivity to the
trilinear coupling via a one-parameter fit to the single Higgs measurements at
the LHC 8 TeV. We find that the bounds on the self coupling are already
competitive with those from Higgs pair production and will be further improved
in the current and next LHC runs.


title:
Complete conservative dynamics for inspiralling compact binaries with
  spins at the fourth post-Newtonian order

abstract:
  In this work we complete the spin-dependent conservative dynamics of
inspiralling compact binaries at the fourth post-Newtonian order, and in
particular the derivation of the next-to-next-to-leading order spin-squared
interaction potential. We derive the physical equations of motion of the
position and the spin from a direct variation of the action. Further, we derive
the quadratic-in-spin Hamiltonians, as well as their expressions in the
center-of-mass frame. We construct the conserved integrals of motion, which
form the Poincar\'e algebra. This construction provided a consistency check for
the validity of our result, which is crucial in particular in the current
absence of another independent derivation of the next-to-next-to-leading order
spin-squared interaction. Finally, we provide here the complete gauge-invariant
relations among the binding energy, angular momentum, and orbital frequency of
an inspiralling binary with generic compact spinning components to the fourth
post-Newtonian order. These high post-Newtonian orders, in particular taking
into account the spins of the binary constituents, will enable to gain more
accurate information on the constituents from even more sensitive
gravitational-wave detections to come.


title:
Strings from Massive Higher Spins: The Asymptotic Uniqueness of the
  Veneziano Amplitude

abstract:
  We consider weakly-coupled theories of massive higher-spin particles. This
class of models includes, for instance, tree-level String Theory and Large-N
Yang-Mills theory. The S-matrix in such theories is a meromorphic function
obeying unitarity and crossing symmetry. We discuss the (unphysical) regime
$s,t \gg 1$, in which we expect the amplitude to be universal and exponentially
large. We develop methods to study this regime and show that the amplitude
necessarily coincides with the Veneziano amplitude there. In particular, this
implies that the leading Regge trajectory, $j(t)$, is asymptotically linear in
Yang-Mills theory. Further, our analysis shows that any such theory of
higher-spin particles has stringy excitations and infinitely many
asymptotically parallel subleading trajectories. More generally, we argue that,
under some assumptions, any theory with at least one higher-spin particle must
have strings.


title: Composing Scalable Nonlinear Algebraic Solvers

abstract:
  Most efficient linear solvers use composable algorithmic components, with the
most common model being the combination of a Krylov accelerator and one or more
preconditioners. A similar set of concepts may be used for nonlinear algebraic
systems, where nonlinear composition of different nonlinear solvers may
significantly improve the time to solution. We describe the basic concepts of
nonlinear composition and preconditioning and present a number of solvers
applicable to nonlinear partial differential equations. We have developed a
software framework in order to easily explore the possible combinations of
solvers. We show that the performance gains from using composed solvers can be
substantial compared with gains from standard Newton-Krylov methods.


title:
Timed Supervisory Control for Operational Planning and Scheduling under
  Multiple Job Deadlines

abstract:
  In this paper, we model an operational planning and scheduling problem under
multiple job deadlines in a time-weighted automaton framework. We first present
a method to determine whether all given job specifications and deadlines can be
met by computing a supremal controllable job satisfaction sublanguage. When
this supremal sublanguage is not empty, we compute one of its controllable
sublanguages that ensures the minimum total job earliness by adding proper
delays. When this supremal sublanguage is empty, we will determine the minimal
sets of job deadlines that need to be relaxed.


title: Android Permission Model

abstract:
  The recent evolution on the smart phone technology has made its application
market huge and less secure. Every single day large number of apps introduced
in the android market (mostly on google play store) without any particular
inspections which creates a lot of security issues and they remain unresolved.
There are a lot of recent and increasing security issues which are mostly
caused by the android apps. Mainly, the access of user data through the apps
relied on the users given permission to apps.So, it is always a big question
that how different apps on the android smart phones bypass the android
permission model to have root access and how user data compromised or stolen by
its apps. It is not startling that the Google Play Store has massive number of
malicious apps that may gain users attention to fall victim for one, but some
time it might be even worse than we thought. In this paper, we will look at the
security issues (i.e. rooting phone, malware bypassing and secondary storage)
and how easy to get access to users phone by using its app.
  Furthermore, I will discuss the android update mechanism and its
functionalities as well as vulnerability to possible third party bypassing and
root access. Moreover, a key feature and source of the all possible access
route to android applications I will discuss an android permission model.
Finally, I will first time present concept of the feature based development
model implementing a feature based permission selections as a solution to
android application system and describe the purposed Feature based permission
model in detail how it is the solution for current security issues caused by
intentional (evil coded) or unintentional (poorly coded) coding using android
permission models.


title:
Generalizing The Mean Spherical Approximation as a Multiscale, Nonlinear
  Boundary Condition at the Solute--Solvent Interface

abstract:
  In this paper we extend the familiar continuum electrostatic model with a
perturbation to the usual macroscopic boundary condition. The perturbation is
based on the mean spherical approximation (MSA), to derive a multiscale
hydration-shell boundary condition (HSBC). We show that the HSBC/MSA model
reproduces MSA predictions for Born ions in a variety of polar solvents,
including both protic and aprotic solvents. Importantly, the HSBC/MSA model
predicts not only solvation free energies accurately but also solvation
entropies, which standard continuum electrostatic models fail to predict. The
HSBC/MSA model depends only on the normal electric field at the dielectric
boundary, similar to our recent development of an HSBC model for charge-sign
hydration asymmetry, and the reformulation of the MSA as a boundary condition
enables its straightforward application to complex molecules such as proteins.


title: Revision of the LHCb Limit on Majorana Neutrinos

abstract:
  We revisit the recent limits from LHCb on a Majorana neutrino N in the mass
range 250 - 5000 MeV. These limits are among the best currently available, and
they will be improved soon by the addition of data from Run 2 of the LHC. LHCb
presented a model-independent constraint on the rate of like-sign leptonic
decays, and then derived a constraint on the mixing angle V{\mu}4 based on a
theoretical model for the B decay width to N and the N lifetime. The model used
is unfortunately unsound. We revise the conclusions of the paper based on a
decay model similar to the one used for the tau lepton and provide formulae
useful for future analyses.


title:
Isometrische Einbettung von geschlossenen Riemannschen
  Mannigfaltigkeiten

abstract:
  In this work we give a detailed description of Matthias G\"unther's proof of
the Isometric Embedding Theorem of Riemannian manifolds. Subsequently we will
use this method to show that it is possible to construct an isometric embedding
of a geometric flow, for instance the Ricci-flow, into some Euclidean space.


title:
Effects of Bulk Composition on The Atmospheric Dynamics on Close-in
  Exoplanets

abstract:
  Super Earths and mini Neptunes likely have a wide range of atmospheric
compositions, ranging from low-molecular mass atmospheres of H2 to higher
molecular atmospheres of water, CO2, N2, or other species. Here, we
systematically investigate the effects of atmospheric bulk compositions on
temperature and wind distributions for tidally locked sub-Jupiter-sized
planets, using an idealized 3D general circulation model (GCM). The bulk
composition effects are characterized in the framework of two independent
variables: molecular weight and molar heat capacity. The effect of molecular
weight dominates. As the molecular weight increases, the atmosphere tends to
have a larger day-night temperature contrast, a smaller eastward phase shift in
the thermal phase curve and a smaller zonal wind speed. The width of the
equatorial super-rotating jet also becomes narrower and the "jet core" region,
where the zonal-mean jet speed maximizes, moves to a greater pressure level.
The zonal-mean zonal wind is more prone to exhibit a latitudinally alternating
pattern in a higher-molecular-weight atmosphere. We also present analytical
theories that quantitatively explain the above trends and shed light on the
underlying dynamical mechanisms. Those trends might be used to indirectly
determine the atmospheric compositions on tidally locked sub-Jupiter-sized
planets. The effects of the molar heat capacity are generally small. But if the
vertical temperature profile is close to adiabatic, molar heat capacity will
play a significant role in controlling the transition from a divergent flow in
the upper atmosphere to a jet-dominated flow in the lower atmosphere.


title:
Molecular Dynamics Analysis of Graphene-Based Nanoelectromechanical
  Switch

abstract:
  Here we present graphene-based nanoelectromechanical switch with the vertical
carbon nanotube electrode via classical molecular dynamics simulations. The
carbon nanotube is grown in the center of the square hole and the graphene
covers on the hole. The potential difference between the bottom of the hole and
the graphene is applied to deflect the graphene. By performing classical
molecular dynamic simulations, we investigate the electromechanical properties
of graphene-based nanoelectro- mechanical switch with carbon nanotube
electrode, which can be switched by the externally applied force. This
simulation work explicitly demonstrated that such devices are applicable to
nanoscale sensors and quantum computing, as well as ultra-fast-response
switching devices.


title: Discovery of a high state AM CVn binary in the Galactic Bulge Survey

abstract:
  We report on the discovery of a hydrogen-deficient compact binary (CXOGBS
J175107.6-294037) belonging to the AM CVn class in the Galactic Bulge Survey.
Deep archival X-ray observations constrain the X-ray positional uncertainty of
the source to 0.57 arcsec, and allow us to uniquely identify the optical and UV
counterpart. Optical spectroscopic observations reveal the presence of broad,
shallow He i absorption lines while no sign of hydrogen is present, consistent
with a high state system. We present the optical lightcurve from Optical
Gravitational Lensing Experiment monitoring, spanning 15 years. It shows no
evidence for outbursts; variability is present at the 0.2 mag level on
timescales ranging from hours to weeks. A modulation on a timescale of years is
also observed. A Lomb-Scargle analysis of the optical lightcurves shows two
significant periodicities at 22.90 and 23.22 min. Although the physical
interpretation is uncertain, such timescales are in line with expectations for
the orbital and superhump periods. We estimate the distance to the source to be
between 0.5 - 1.1 kpc. Spectroscopic follow-up observations are required to
establish the orbital period, and to determine whether this source can serve as
a verification binary for the eLISA gravitational wave mission.


title:
The Limits of Popularity-Based Recommendations, and the Role of Social
  Ties

abstract:
  In this paper we introduce a mathematical model that captures some of the
salient features of recommender systems that are based on popularity and that
try to exploit social ties among the users. We show that, under very general
conditions, the market always converges to a steady state, for which we are
able to give an explicit form. Thanks to this we can tell rather precisely how
much a market is altered by a recommendation system, and determine the power of
users to influence others. Our theoretical results are complemented by
experiments with real world social networks showing that social graphs prevent
large market distortions in spite of the presence of highly influential users.


title: Evidence for the magnetar nature of 1E 161348-5055 in RCW 103

abstract:
  We report on the detection of a bright, short, structured X-ray burst coming
from the supernova remnant RCW 103 on 2016 June 22 caught by the Swift/BAT
monitor, and on the follow-up campaign made with Swift/XRT, Swift/UVOT and the
optical/NIR GROND detector. The characteristics of this flash, such as
duration, and spectral shape, are consistent with typical short bursts observed
from soft gamma repeaters. The BAT error circle at 68 per cent confidence range
encloses the point-like X-ray source at the centre of the nebula,
1E161348-5055. Its nature has been long debated due to a periodicity of 6.67 hr
in X-rays, which could indicate either an extremely slow pulsating neutron
star, or the orbital period of a very compact X-ray binary system. We found
that 20 min before the BAT trigger, the soft X-ray emission of 1E161348-5055
was a factor of ~100 higher than measured 2 yr earlier, indicating that an
outburst had already started. By comparing the spectral and timing
characteristics of the source in the two years before the outburst and after
the BAT event, we find that, besides a change in luminosity and spectral shape,
also the 6.67 hr pulsed profile has significantly changed with a clear phase
shift with respect to its low-flux profile. The UV/optical/NIR observations did
not reveal any counterpart at the position of 1E161348-5055. Based on these
findings, we associate the BAT burst with 1E161348-5055, we classify it as a
magnetar, and pinpoint the 6.67 hr periodicity as the magnetar spin period.


title:
Branes in Extended Spacetime: Brane Worldvolume Theory Based on Duality
  Symmetry

abstract:
  We propose a novel approach to the brane worldvolume theory based on the
geometry of extended field theories: double field theory and exceptional field
theory. We demonstrate the effectiveness of this approach by showing that one
can reproduce the conventional bosonic string and membrane actions, and the
M5-brane action in the weak-field approximation. At a glance, the proposed
5-brane action without approximation looks different from the known M5-brane
actions, but it is consistent with the known nonlinear self-duality relation,
and it may provide a new formulation of a single M5-brane action. Actions for
exotic branes are also discussed.


title:
How bright is the proton? A precise determination of the photon parton
  distribution function

abstract:
  It has become apparent in recent years that it is important, notably for a
range of physics studies at the Large Hadron Collider, to have accurate
knowledge on the distribution of photons in the proton. We show how the photon
parton distribution function (PDF) can be determined in a model-independent
manner, using electron-proton ($ep$) scattering data, in effect viewing the
$ep\to e+X$ process as an electron scattering off the photon field of the
proton. To this end, we consider an imaginary, beyond Standard Model process
with a flavour changing photon-lepton vertex. We write its cross section in two
ways, one in terms of proton structure functions, the other in terms of a
photon distribution. Requiring their equivalence yields the photon distribution
as an integral over proton structure functions. As a result of the good
precision of $ep$ data, we constrain the photon PDF at the level of 1-2% over a
wide range of momentum fractions.


title: Enhanced Boolean Correlation Matrix Memory

abstract:
  This paper introduces an Enhanced Boolean version of the Correlation Matrix
Memory (CMM), which is useful to work with binary memories. A novel Boolean
Orthonormalization Process (BOP) is presented to convert a non-orthonormal
Boolean basis, i.e., a set of non-orthonormal binary vectors (in a Boolean
sense) to an orthonormal Boolean basis, i.e., a set of orthonormal binary
vectors (in a Boolean sense). This work shows that it is possible to improve
the performance of Boolean CMM thanks BOP algorithm. Besides, the BOP algorithm
has a lot of additional fields of applications, e.g.: Steganography, Hopfield
Networks, Bi-level image processing, etc. Finally, it is important to mention
that the BOP is an extremely stable and fast algorithm.


title:
Inhomogeneous Weyl and Dirac semimetals: Transport in axial magnetic
  fields and Fermi arc surface states from pseudo Landau levels

abstract:
  Topological Dirac and Weyl semimetals have an energy spectrum that hosts Weyl
nodes appearing in pairs of opposite chirality. Topological stability is
ensured when the nodes are separated in momentum space and unique spectral and
transport properties follow. In this work we study the effect of a space
dependent Weyl node separation, which we interpret as an emergent background
axial vector potential, on the electromagnetic response and the energy spectrum
of Weyl and Dirac semimetals. This situation can arise in the solid state
either from inhomogeneous strain or non-uniform magnetization and can also be
engineered in cold-atomic systems. Using a semiclassical approach we show that
the resulting axial magnetic field $\mathbf{B}_{5}$ is observable through an
enhancement of the conductivity as $\sigma\sim \mathbf{B}_{5} ^{2}$ due to an
underlying chiral pseudo magnetic effect. We then use two lattice models to
analyze the effect of $\mathbf{B}_5$ on the spectral properties of topological
semimetals. We describe the emergent pseudo-Landau level structure for
different spatial profiles of $\mathbf{B}_5$, revealing that (i) the celebrated
surface states of Weyl semimetals, the Fermi arcs, can be reinterpreted as
$n=0$ pseudo-Landau levels resulting from a $\mathbf{B}_5$ confined to the
surface (ii) as a consequence of position-momentum locking a bulk
$\mathbf{B}_5$ creates pseudo-Landau levels interpolating in real space between
Fermi arcs at opposite surfaces and (iii) there are equilibrium bound currents
proportional to $\mathbf{B}_{5}$ that average to zero over the sample, which
are the analogs of bound currents in magnetic materials. We conclude by
discussing how our findings can be probed experimentally.


title: Zealots tame oscillations in the spatial rock-paper-scissors game

abstract:
  The rock-paper-scissors game is a paradigmatic model for biodiversity, with
applications ranging from microbial populations to human societies. Research
has shown, however, that mobility jeopardizes biodiversity by promoting the
formation of spiral waves, especially if there is no conservation law in place
for the total number of competing players. Firstly, we show that even if such a
conservation law applies, mobility still jeopardizes biodiversity in the
spatial rock-paper-scissors game if only a small fraction of links of the
square lattice is randomly rewired. Secondly, we show that zealots are very
effective in taming the amplitude of oscillations that emerge due to mobility
and/or interaction randomness, and this regardless of whether the later is
quenched or annealed. While even a tiny fraction of zealots brings significant
benefits, at 5\% occupancy zealots practically destroy all oscillations
regardless of the intensity of mobility, and regardless of the type and
strength of randomness in the interaction structure. Interestingly, by annealed
randomness the impact of zealots is qualitatively the same as by mobility,
which highlights that fast diffusion does not necessarily destroy the
coexistence of species, and that zealotry thus helps to recover the stable
mean-field solution. Our results strengthen the important role of zealots in
models of cyclic dominance, and they reveal fascinating evolutionary outcomes
in structured populations that are a unique consequence of such uncompromising
behavior.

categories: physics.soc-ph cond-mat.stat-mech physics.bio-ph q-bio.PE


title: Critical behavior in the presence of an order-parameter pinning field

abstract:
  We apply a recently advocated simulation scheme that employs a local
order-parameter pinning field to study quantum critical phenomena in the
two-dimensional square-lattice bilayer quantum Heisenberg model. Using a
world-line quantum Monte Carlo approach, we show that for this model, the
pinning-field approach allows to locate the quantum critical point over a wide
range of pinning-field strengths. However, the identification of the quantum
critical scaling behavior is found to be hard since the pinning field
introduces strong corrections to scaling. In order to further elucidate the
scaling behavior in this situation, we also study an improved classical lattice
model in the three-dimensional Ising universality class by means of Monte Carlo
simulations on large lattice sizes, which allow us to employ refined
finite-size scaling considerations. A renormalization group analysis exhibits
the presence of an important crossover effect from the zero pinning-field to a
critical adsorption fixed point. In line with field-theoretical results, we
find that at the critical adsorption fixed point the short-distance expansion
of the order-parameter profile exhibits a new universal critical exponent. This
result also implies the presence of slowly decaying scaling corrections, which
we analyze in detail.


title: Virtual Specht stability for $FI$-modules in positive characteristic

abstract:
  We define a notion of virtual Specht stability which is a relaxation of the
Church-Farb notion of representation stability for sequences of symmetric group
representations. Using a structural result of Nagpal, we show that $FI$-modules
over fields of positive characteristic exhibit virtual Specht stability.


title:
APSARA: A multi-dimensional unsplit fourth-order explicit Eulerian
  hydrodynamics code for arbitrary curvilinear grids

abstract:
  We present a new fourth-order, finite-volume hydrodynamics code named Apsara.
The code employs a high-order, finite-volume method for mapped coordinates with
extensions for nonlinear hyperbolic conservation laws. Apsara can handle
arbitrary structured curvilinear meshes in three spatial dimensions. The code
has successfully passed several hydrodynamic test problems, including the
advection of a Gaussian density profile and a nonlinear vortex and the
propagation of linear acoustic waves. For these test problems, Apsara produces
fourth-order accurate results in case of smooth grid mappings. The order of
accuracy is reduced to first-order when using the nonsmooth circular grid
mapping. When applying the high-order method to simulations of low-Mach number
flows, for example, the Gresho vortex and the Taylor-Green vortex, we discover
that Apsara delivers superior results to codes based on the dimensionally
split, piecewise parabolic method (PPM) widely used in astrophysics. Hence,
Apsara is a suitable tool for simulating highly subsonic flows in astrophysics.
In the first astrophysical application, we perform implicit large eddy
simulations (ILES) of anisotropic turbulence in the context of core collapse
supernova (CCSN) and obtain results similar to those previously reported.


title:
An Effective Series Expansion to the Equation of State of Unitary Fermi
  Gases

abstract:
  Using universal properties and a basic statistical mechanical approach, we
propose a general equation of state for unitary Fermi gases. The universal
equation of state is written as a series solution to a self consistent integral
equation where the general solution is a linear combination of Fermi functions.
First, by truncating our series solution to four terms with already known exact
theoretical inputs at limiting cases, namely the first \emph{three} virial
coefficients and using the Bertsch parameter as a free parameter, we find a
good agreement with experimental measurements in the entire temperature region
in the normal state. This analytical equation of state agrees with experimental
data up to the fugacity $z = 18$, which is a vast improvement over the other
analytical equations of state available where the agreements is \emph{only} up
to $z \approx 7$. Second, by truncating our series solution to four terms again
using first \emph{four} virial coefficients, we find the Bertsch parameter $\xi
=0.35$, which is in good agreement with the direct experimental measurement of
$\xi =0.37$. This second form of equation of state shows a good agreement with
self-consistent T-matrix calculations in the normal phase.


title: An introduction to linear poroelasticity

abstract:
  This study is an introduction to the theory of three-dimensional
consolidation. The point of departure in the description are the basic
equations of elasticity (i.e. constitutive law, equations of equilibrium in
terms of stresses, and the definition of strain), together with the principle
of effective stress, and the law of Darcy for fluid flow in porous media. These
equations, together with the principle of mass conservation, are the only
premises used to derive a drained description of consolidation theory. Next,
the increment of fluid content is defined and its constitutive law is derived -
with its derivation following naturally from the equation of fluid mass
balance. Pore pressure, storage, and undrained coefficients are also introduced
and useful relations are proven. Where appropriate, the physical meaning of
these coefficients is proven mathematically. Equations of equilibrium and fluid
mass conservation are subsequently expressed in terms of the increment of fluid
content and undrained coefficients, leading to an undrained description of
consolidation theory. Thus the initial approach of using drained description is
extended to the formalism of Rice and Cleary. This approach to
three-dimensional consolidation is useful for its simplicity. It does not
require the ad-hoc definition of constants and that of an elastic energy
potential. Instead, it is a direct extension to linear elasticity that accounts
for the coupling of skeletal deformations and fluid behaviour.


title:
The Scaling of Stellar Mass and Central Stellar Velocity Dispersion for
  Quiescent galaxies at z < 0.7

abstract:
  We examine the relation between stellar mass and central stellar velocity
dispersion-the M-sigma relation-for massive quiescent galaxies at z<0.7. We
measure the local relation from the Sloan Digital Sky Survey and the
intermediate redshift relation from the Smithsonian Hectospec Lensing Survey.
Both samples are highly complete (>85%) and we consistently measure the stellar
mass and velocity dispersion for the two samples. The M-sigma relation and its
scatter are independent of redshift with sigma ~ M^0.3 for M>10^10.3 M_solar.
The measured slope of the M-sigma relation is the same as the scaling between
the total halo mass and the dark matter halo velocity dispersion obtained by
N-body simulations. This consistency suggests that massive quiescent galaxies
are virialized systems where the central dark matter concentration is either a
constant or negligible fraction of the stellar mass. The relation between the
total galaxy mass (stellar + dark matter) and the central stellar velocity
dispersion is consistent with the observed relation between the total mass of a
galaxy cluster and the velocity dispersion of the cluster members. This result
suggests that the central stellar velocity dispersion is directly proportional
to the velocity dispersion of the dark matter halo. Thus the central stellar
velocity dispersion is a fundamental, directly observable property of galaxies
that may robustly connect galaxies to dark matter halos in N-body simulations.
To interpret the results further in the context of Lambda-CDM, it would be
useful to analyze the relationship between the velocity dispersion of stellar
particles and the velocity dispersion characterizing their dark matter halos in
high-resolution cosmological hydrodynamic simulations.


title: Breakdown of Effective Field Theory for a Gluon Initiated Resonance

abstract:
  Gauge invariance dictates that a resonance produced from initial state gluons
must be produced through a non-renormalizable operator or a loop process.
Should such a resonance be discovered, uncovering the dynamics that give rise
to its couplings to gluons will be crucial to understanding the nature of the
new state. Here we study how the production of this resonance at high
transverse momentum in association with one (or more) jets can be used to
directly measure the scale of the operator or the mass of the particles in the
loop. We use a 750 GeV diphoton resonance as an example application, and we
study how the non-renormalizable operator case can be described by a slowly
converging effective field theory (EFT) expansion with operators of dimension
five and seven. We show that with O(100) events, one can put strong constraints
on the scale of the EFT, particularly in theories with strong coupling. We also
compare the EFT analysis to that of a UV completion with vector-like quarks,
and outline how the mass of said quarks could be measured.


title:
The imprint of pulsar parameters on the morphology of Pulsar Wind
  Nebulae

abstract:
  The morphology of young Pulsar Wind Nebulae (PWN) is largely determined by
the properties of the wind injected by the pulsar. We have used a recent
parametrization of the wind obtained from Force Free Electrodynamics
simulations of pulsar magnetospheres to simulate nebulae for different sets of
pulsar parameters. We performed axisymmetric Relativistic Magnetohydrodynamics
simulations to test the morphology dependence of the nebula on the obliquity of
the pulsar and on the magnetization of the pulsar wind. We compare these
simulations to the morphology of the Vela and Crab PWN. We find that the
morphology of Vela can be reproduced qualitatively if the pulsar obliquity
angle is alpha ~45deg and the magnetization of the wind is high (sigma_0 ~
3.0). A morphology similar to the one of the Crab Nebula is only obtained for
low magnetization simulations with alpha >~ 45deg. Interestingly, we find that
Kelvin-Helmholtz instabilities produce small scale turbulences downstream of
the reverse shock of the pulsar wind.


title: Dark Gamma Ray Bursts

abstract:
  Many theories of dark matter (DM) predict that DM particles can be captured
by stars via scattering on ordinary matter. They subsequently condense into a
DM core close to the center of the star and eventually annihilate. In this
work, we trace DM capture and annihilation rates throughout the life of a
massive star and show that this evolution culminates in an intense annihilation
burst coincident with the death of the star in a core collapse supernova. The
reason is that, along with the stellar interior, also its DM core heats up and
contracts, so that the DM density increases rapidly during the final stages of
stellar evolution. We argue that, counterintuitively, the annihilation burst is
more intense if DM annihilation is a $p$-wave process than for $s$-wave
annihilation because in the former case, more DM particles survive until the
supernova. If among the DM annihilation products are particles like dark
photons that can escape the exploding star and decay to Standard Model
particles later, the annihilation burst results in a flash of gamma rays
accompanying the supernova. For a galactic supernova, this "dark gamma ray
burst" may be observable in CTA.


title: Bursty star formation feedback and cooling outflows

abstract:
  We study how outflows of gas launched from a central galaxy undergoing
repeated starbursts propagate through the circumgalactic medium (CGM), using
the simulation code RAMSES. We assume that the outflow from the disk can be
modelled as a rapidly moving bubble of hot gas at $\mathrm{\sim1\;kpc}$ above
disk, then ask what happens as it moves out further into the halo around the
galaxy on $\mathrm{\sim 100\;kpc}$ scales. To do this we run 60 two-dimensional
simulations scanning over parameters of the outflow. Each of these is repeated
with and without radiative cooling, assuming a primordial gas composition to
give a lower bound on the importance of cooling. In a large fraction of
radiative-cooling cases we are able to form rapidly outflowing cool gas from in
situ cooling of the flow. We show that the amount of cool gas formed depends
strongly on the 'burstiness' of energy injection; sharper, stronger bursts
typically lead to a larger fraction of cool gas forming in the outflow. The
abundance ratio of ions in the CGM may therefore change in response to the
detailed historical pattern of star formation. For instance, outflows generated
by star formation with short, intense bursts contain up to 60 per cent of their
gas mass at temperatures $<5 \times 10^4\,\mathrm{K}$; for near-continuous star
formation the figure is $\lesssim$ 5 per cent. Further study of cosmological
simulations, and of idealised simulations with e.g., metal-cooling, magnetic
fields and/or thermal conduction, will help to understand the precise signature
of bursty outflows on observed ion abundances.


title:
Constraining the Movement of the Spiral Features and the Locations of
  Planetary Bodies within the AB Aur System

abstract:
  We present new analysis of multi-epoch, H-band, scattered light images of the
AB Aur system. We used a Monte Carlo, radiative transfer code to simultaneously
model the system's SED and H-band polarized intensity imagery. We find that a
disk-dominated model, as opposed to one that is envelope dominated, can
plausibly reproduce AB Aur's SED and near-IR imagery. This is consistent with
previous modeling attempts presented in the literature and supports the idea
that at least a subset of AB Aur's spirals originate within the disk. In light
of this, we also analyzed the movement of spiral structures in multi-epoch
H-band total light and polarized intensity imagery of the disk. We detect no
significant rotation or change in spatial location of the spiral structures in
these data, which span a 5.8 year baseline. If such structures are caused by
disk-planet interactions, the lack of observed rotation constrains the location
of the orbit of planetary perturbers to be >47 AU.


title: N=1 Deformations and RG Flows of N=2 SCFTs

abstract:
  We study certain N=1 preserving deformations of four-dimensional N=2
superconformal field theories (SCFTs) with non-abelian flavor symmetry. The
deformation is described by adding an N=1 chiral multiplet transforming in the
adjoint representation of the flavor symmetry with a superpotential coupling,
and giving a nilpotent vacuum expectation value to the chiral multiplet which
breaks the flavor symmetry. This triggers a renormalization group flow to an
infrared SCFT. Remarkably, we find classes of theories flow to enhanced N=2
supersymmetric fixed points in the infrared under the deformation. They include
generalized Argyres-Douglas theories and rank-one SCFTs with non-abelian flavor
symmetries. Most notably, we find renormalization group flows from the deformed
conformal SQCDs to the $(A_1, A_n)$ Argyres-Douglas theories. From these
"Lagrangian descriptions," we compute the full superconformal indices of the
$(A_1, A_n)$ theories and find agreements with the previous results.
Furthermore, we study the cases, including the $T_N$ and $R_{0,N}$ theories of
class $\mathcal{S}$ and some of rank-one SCFTs, where the deformation gives
genuine N=1 fixed points.


title: The unseen planets of double belt debris disk systems

abstract:
  The gap between two component debris disks is often taken to be carved by
intervening planets scattering away the remnant planetesimals. We employ N-body
simulations to determine how the time needed to clear the gap depends on the
location of the gap and the mass of the planets. We invert this relation, and
provide an equation for the minimum planet mass, and another for the expected
number of such planets, that must be present to produce an observed gap for a
star of a given age. We show how this can be combined with upper limits on the
planetary system from direct imaging non-detections (such as with GPI or
SPHERE) to produce approximate knowledge of the planetary system.


title:
Evolution of cosmic star formation in the SCUBA-2 Cosmology Legacy
  Survey

abstract:
  We present a new exploration of the cosmic star-formation history and dust
obscuration in massive galaxies at redshifts $0.5< z<6$. We utilize the deepest
450 and 850$\mu$m imaging from SCUBA-2 CLS, covering 230arcmin$^2$ in the
AEGIS, COSMOS and UDS fields, together with 100-250$\mu$m imaging from
Herschel. We demonstrate the capability of the T-PHOT deconfusion code to reach
below the confusion limit, using multi-wavelength prior catalogues from
CANDELS/3D-HST. By combining IR and UV data, we measure the relationship
between total star-formation rate (SFR) and stellar mass up to $z\sim5$,
indicating that UV-derived dust corrections underestimate the SFR in massive
galaxies. We investigate the relationship between obscuration and the UV slope
(the IRX-$\beta$ relation) in our sample, which is similar to that of
low-redshift starburst galaxies, although it deviates at high stellar masses.
Our data provide new measurements of the total SFR density (SFRD) in
$M_\ast>10^{10}M_\odot$ galaxies at $0.5<z<6$. This is dominated by obscured
star formation by a factor of $>10$. One third of this is accounted for by
450$\mu$m-detected sources, while one fifth is attributed to UV-luminous
sources (brighter than $L^\ast_{UV}$), although even these are largely
obscured. By extrapolating our results to include all stellar masses, we
estimate a total SFRD that is in good agreement with previous results from IR
and UV data at $z\lesssim3$, and from UV-only data at $z\sim5$. The cosmic
star-formation history undergoes a transition at $z\sim3-4$, as predominantly
unobscured growth in the early Universe is overtaken by obscured star
formation, driven by the build-up of the most massive galaxies during the peak
of cosmic assembly.


title: A semi-analytic dynamical friction model for cored galaxies

abstract:
  We present a dynamical friction model based on Chandrasekhar's formula that
reproduces the fast inspiral and stalling experienced by satellites orbiting
galaxies with a large constant density core. We show that the fast inspiral
phase does not owe to resonance. Rather, it owes to the background velocity
distribution function for the constant density cores being dissimilar from the
usually-assumed Maxwellian distribution. Using the correct background velocity
distribution function and the semi-analytic model from Petts et al. (2015), we
are able to correctly reproduce the infall rate in both cored and cusped
potentials. However, in the case of large cores, our model is no longer able to
correctly capture core-stalling. We show that this stalling owes to the tidal
radius of the satellite approaching the size of the core. By switching off
dynamical friction when rt(r) = r (where rt is the tidal radius at the
satellite's position) we arrive at a model which reproduces the N-body results
remarkably well. Since the tidal radius can be very large for constant density
background distributions, our model recovers the result that stalling can occur
for Ms/Menc << 1, where Ms and Menc are the mass of the satellite and the
enclosed galaxy mass, respectively. Finally, we include the contribution to
dynamical friction that comes from stars moving faster than the satellite. This
next-to-leading order effect becomes the dominant driver of inspiral near the
core region, prior to stalling.


title: Interpreting the evolution of galaxy colours from $z = 8$ to $z = 5$

abstract:
  We attempt to interpret existing data on the evolution of the UV luminosity
function and UV colours, $\beta$, of galaxies at $5 \leq z \leq 8$, to improve
our understanding of their dust content and ISM properties. To this aim, we
post-process the results of a cosmological hydrodynamical simulation with a
chemical evolution model, which includes dust formation by supernovae and
intermediate mass stars, dust destruction in supernova shocks, and grain growth
by accretion of gas-phase elements in dense gas. We find that observations
require a steep, Small Magellanic Cloud-like extinction curve and a clumpy dust
distribution, where stellar populations younger than 15 Myr are still embedded
in their dusty natal clouds. Investigating the scatter in the colour
distribution and stellar mass, we find that the observed trends can be
explained by the presence of two populations: younger, less massive galaxies
where dust enrichment is mainly due to stellar sources, and massive, more
chemically evolved ones, where efficient grain growth provides the dominant
contribution to the total dust mass. Computing the IR-excess - UV color
relation we find that all but the dustiest model galaxies follow a relation
shallower than the Meurer et al. (1999) one, usually adopted to correct the
observed UV luminosities of high-$z$ galaxies for the effects of dust
extinction. As a result, their total star formation rates might have been
over-estimated. Our study illustrates the importance to incorporate a proper
treatment of dust in simulations of high-$z$ galaxies, and that massive, dusty,
UV-faint galaxies might have already appeared at $z \lesssim 7$.


title: Radial vibrations of BPS skyrmions

abstract:
  We study radial vibrations of spherically symmetric skyrmions in the BPS
Skyrme model. Concretely, we numerically solve the linearised field equations
for small fluctuations in a skyrmion background, both for linearly stable
oscillations and for (unstable) resonances. This is complemented by numerical
solutions of the full nonlinear system, which confirm all the results of the
linear analysis. In all cases, the resulting fundamental excitation provides a
rather accurate value for the Roper resonance, supporting the hypothesis that
the BPS Skyrme model already gives a reasonable approximate description of this
resonance. Further, for many potentials additional higher resonances appear,
again in agreement with known experimental results.


title: Linear Diophantine Equations, Group CSPs, and Graph Isomorphism

abstract:
  In recent years, we have seen several approaches to the graph isomorphism
problem based on "generic" mathematical programming or algebraic (Gr\"obner
basis) techniques. For most of these, lower bounds have been established. In
fact, it has been shown that the pairs of nonisomorphic CFI-graphs (introduced
by Cai, F\"urer, and Immerman in 1992 as hard examples for the combinatorial
Weisfeiler-Leman algorithm) cannot be distinguished by these mathematical
algorithms. A notable exception were the algebraic algorithms over the field
GF(2), for which no lower bound was known. Another, in some way even stronger,
approach to graph isomorphism testing is based on solving systems of linear
Diophantine equations (that is, linear equations over the integers), which is
known to be possible in polynomial time. So far, no lower bounds for this
approach were known.
  Lower bounds for the algebraic algorithms can best be proved in the framework
of proof complexity, where they can be phrased as lower bounds for algebraic
proof systems such as Nullstellensatz or the (more powerful) polynomial
calculus. We give new hard examples for these systems: families of pairs of
non-isomorphic graphs that are hard to distinguish by polynomial calculus
proofs simultaneously over all prime fields, including GF(2), as well as
examples that are hard to distinguish by the
systems-of-linear-Diophantine-equations approach.
  In a previous paper, we observed that the CFI-graphs are closely related to
what we call "group CSPs": constraint satisfaction problems where the
constraints are membership tests in some coset of a subgroup of a cartesian
power of a base group (Z_2 in the case of the classical CFI-graphs). Our new
examples are also based on group CSPs (for Abelian groups), but here we extend
the CSPs by a few non-group constraints to obtain even harder instances for
graph isomorphism.


title: Very Degenerate Higgsino Dark Matter

abstract:
  We present a study of the Very Degenerate Higgsino Dark Matter (DM), whose
mass splitting between the lightest neutral and charged components is ${\cal
O}$(1) MeV, much smaller than radiative splitting of 355 MeV. The scenario is
realized in the minimal supersymmetric standard model by small gaugino mixing.
In contrast to the pure Higgsino DM with the radiative splitting only, various
observable signatures with distinct features are induced. First of all, the
very small mass splitting makes (a) sizable Sommerfeld enhancement and
Ramsauer-Townsend (RT) suppression relevant to ~1 TeV Higgsino DM, and (b)
Sommerfeld-Ramsauer-Townsend effect saturate at lower velocities $v/c \lesssim
10^{-3}$. As a result, annihilation signals can be large enough to be observed
from the galactic center and/or dwarf galaxies, while relative signal sizes can
vary depending on the location of Sommerfeld peaks and RT dips. In addition, at
collider experiments, stable chargino signature can be searched for to probe
the model in the future. DM direct detection signal, however, depends on the
Wino mass; even no detectable signal can be induced if the Wino is heavier than
about 10 TeV.


title: X-ray Twinkles and Pop III Stars

abstract:
  Pop III stars are typically massive stars of primordial composition forming
at the centers of the first collapsed dark matter structures. Here we estimate
the optimal X-ray emission in the early universe for promoting the formation of
Pop III stars. This is important in determining the number of dwarf galaxies
formed before reionization and their fossils in the local universe, as well as
the number of intermediate-mass seed black holes. A mean X-ray emission per
source above the optimal level reduces the number of Pop III stars because of
the increased Jeans mass of the intergalactic medium (IGM), while a lower
emission suppresses the formation rate of H2 preventing or delaying star
formation in dark matter minihalos above the Jeans mass. The build up of the H2
dissociating background is slower than the X-ray background due to the
shielding effect of resonant hydrogen Lyman lines. Hence, the nearly
unavoidable X-ray emission from supernova remnants of Pop III stars is
sufficient to boost their number to few tens per comoving Mpc^3 by redshift
z~15. We find that there is a critical X-ray to UV energy ratio emitted per
source that produces a universe where the number of Pop III stars is largest:
400 per comoving- Mpc^3. This critical ratio is very close to the one provided
by 20-40 M_sun Pop III stars exploding as hypernovae. High mass X-ray binaries
in dwarf galaxies are far less effective at increasing the number of Pop III
stars than normal supernova remnants, we thus conclude that supernovae drove
the formation of Pop III stars.


title:
FEMSIM+HRMC: Simulation of and Structural Refinement using Fluctuation
  Electron Microscopy for Amorphous Materials

abstract:
  FEMSIM, a Fortran code, has been developed to simulate the fluctuation
electron microscopy signal, the variance, V(k), from a model atomic structure.
FEMSIM has been incorporated into a hybrid-reverse Monte Carlo code that
combines an embedded atom or Finnis-Sinclair potential with the deviation
between simulated and experimental V(k) data to refine an atomic model with
structure constrained by both the potential and experimental data. The
resulting models have experimentally-derived medium-range order.


title:
A Common Origin for Globular Clusters and Ultra-faint Dwarfs in
  Simulations of the First Galaxies

abstract:
  In this paper, the first in a series on galaxy formation before reionization,
we focus on understanding what determines the size and morphology of stellar
objects in the first low mass galaxies, using parsec- scale cosmological
simulations performed with an adaptive mesh hydrodynamics code. Although the
dense gas in which stars are formed tends to have a disk structure, stars are
found in spheroids with little rotation. Halos with masses between 10^6 M_sun
and 5x10^8 M_sun form stars stochastically, with stellar masses in the range
10^4 M_sun to 2x10^6 M_sun. Nearly independent of stellar mass, we observe a
large range of half-light radii for the stars, from a few parsecs to a few
hundred parsecs and surface brightnesses and mass-to-light ratios ranging from
those typical of globular clusters to ultra-faint dwarfs. In our simulations,
stars form in dense stellar clusters with high gas-to-star conversion
efficiencies and rather uniform metallicities. A fraction of these clusters
remain bound after the gas is removed by feedback, but others are destroyed,
and their stars, which typically have velocity dispersions of 20 to 40 km/s,
expand until they become bound by the dark matter halo. We thus speculate that
the stars in ultra-faint dwarf galaxies may show kinematic and chemical
signatures consistent with their origin in a few distinct stellar clusters. On
the other hand, some globular clusters may form at the center of primordial
dwarf galaxies and may contain dark matter, perhaps detectable in the outer
parts.


title: RoboPol: Do optical polarization rotations occur in all blazars?

abstract:
  We present a new set of optical polarization plane rotations in blazars,
observed during the third year of operation of RoboPol. The entire set of
rotation events discovered during three years of observations is analysed with
the aim of determining whether these events are inherent in all blazars. It is
found that the frequency of the polarization plane rotations varies widely
among blazars. This variation cannot be explained either by a difference in the
relativistic boosting or by selection effects caused by a difference in the
average fractional polarization. We conclude that the rotations are
characteristic of a subset of blazars and that they occur as a consequence of
their intrinsic properties.


title:
Examining the Accuracy of Astrophysical Disk Simulations With a
  Generalized Hydrodynamical Test Problem

abstract:
  We discuss a generalization of the classic Keplerian disk test problem
allowing for both pressure and rotational support, as a method of testing
astrophysical codes incorporating both gravitation and hydrodynamics. We argue
for the inclusion of pressure in rotating disk simulations on the grounds that
realistic, astrophysical disks exhibit non-negligible pressure support. We then
apply this test problem to examine the performance of various smoothed particle
hydrodynamics (SPH) methods incorporating a number of improvements proposed
over the years to help SPH better address problems noted in modeling the
classical gravitation only Keplerian disk. We also apply this test to a newly
developed extension of SPH based on reproducing kernels called CRKSPH.
Counterintuitively, we find that pressure support worsens the performance of
traditional SPH on this problem, causing unphysical collapse away from the
steady-state disk solution even more rapidly than the purely gravitational
problem, whereas CRKSPH greatly reduces this error.


title: Cosmological Perturbations of Axion with a Dynamical Decay Constant

abstract:
  A QCD axion with a time-dependent decay constant has been known to be able to
accommodate high-scale inflation without producing topological defects or too
large isocurvature perturbations on CMB scales. We point out that a dynamical
decay constant also has the effect of enhancing the small-scale axion
isocurvature perturbations. The enhanced axion perturbations can even exceed
the periodicity of the axion potential, and thus lead to the formation of
axionic domain walls. Unlike the well-studied axionic walls, the walls produced
from the enhanced perturbations are not bounded by cosmic strings, and thus
would overclose the universe independently of the number of degenerate vacua
along the axion potential.


title: A minimal partition problem with trace constraint in the Grushin plane

abstract:
  We study a variational problem for the perimeter associated with the Grushin
plane, called minimal partition problem with trace constraint. This consists in
studying how to enclose three prescribed areas in the Grushin plane, using the
least amount of perimeter, under an additional "one-dimensional" constraint on
the intersections of their boundaries. We prove existence of regular solutions
for this problem, and we characterize them in terms of isoperimetric sets,
showing differences with the Euclidean case. The problem arises from the study
of quantitative isoperimetric inequalities and has connections with the theory
of minimal clusters.


title: The Deligne-Mostow list and special families of surfaces

abstract:
  We study whether there exist infinitely many surfaces with given discrete
invariants for which the H^2 is of CM type. This is a surface analogue of a
conjecture of Coleman about curves. We construct a large number of examples of
families of surfaces with p_g = 1 that in the moduli space cut out a special
subvariety; these provide a positive answer to our question. Most of these are
families of K3 surfaces but we also obtain some families of surfaces of general
type. As input for our construction we use the work of Deligne and Mostow.
Finally we prove that a very general K3 surface cannot be dominated by a
product of curves of small genus.


title:
Kinematics and Structure of Clumps in Broad-line Regions in Active
  Galactic Nuclei

abstract:
  We use the Jeans equations for an ensemble of collisionless particles to
describe the distribution of broad-line region (BLR) cloud in three classes:
(A) non disc (B) disc-wind (c) pure disc structure. We propose that clumpy
structures in the brightest quasars belong to class A, fainter quasars and
brighter Seyferts belong to class B, and dimmer Seyfert galaxies and all
low-luminosity AGNs (LLAGNs) belong to class C. We derive the virial factor,
$f$, for disc-like structures and find a negative correlation between the
inclination angle, $\theta_{0}$, and $f$. We find similar behaviour for $f$ as
a function of the FWHM and $\sigma_{z}$, the $z$ component of velocity
dispersion. For different values of $\theta_{0}$ we find that $ 1.0 \lesssim f
\lesssim 9.0 $ in type1 AGNs and $ 0.5 \lesssim f \lesssim 1.0 $ in type2 AGNs.
Moreover we have $ 0.5 \lesssim f \lesssim 6.5 $ for different values of FWHM
and $ 1.4 \lesssim f \lesssim 1.8 $ for different values of $ \sigma_{z} $. We
also find that $ f $ is relatively insensitive to the variations of bolometric
luminosity and column density of each cloud and the range of variation of $ f $
is in order of 0.01. Considering wide range of $ f $ we see the use of average
virial factor $ \langle f \rangle $ is not very safe. Therefore we propose AGN
community to divide a sample into a few subsamples based on the value of $
\theta_{0}$ and FWHM of members and calculate $ \langle f \rangle $ for each
group separately to reduce uncertainty in black hole mass estimation.


title:
Optimal Placement of Cores, Caches and Memory Controllers in Network
  On-Chip

abstract:
  Parallel programming is emerging fast and intensive applications need more
resources, so there is a huge demand for on-chip multiprocessors. Accessing L1
caches beside the cores are the fastest after registers but the size of private
caches cannot increase because of design, cost and technology limits. Then
split I-cache and D-cache are used with shared LLC (last level cache). For a
unified shared LLC, bus interface is not scalable, and it seems that
distributed shared LLC (DSLLC) is a better choice. Most of papers assume a
distributed shared LLC beside each core in on-chip network. Many works assume
that DSLLCs are placed in all cores; however, we will show that this design
ignores the effect of traffic congestion in on-chip network. In fact, our work
focuses on optimal placement of cores, DSLLCs and even memory controllers to
minimize the expected latency based on traffic load in a mesh on-chip network
with fixed number of cores and total cache capacity. We try to do some
analytical modeling deriving intended cost function and then optimize the mean
delay of the on-chip network communication. This work is supposed to be
verified using some traffic patterns that are run on CSIM simulator.


title: Extracting Information from AGN Variability

abstract:
  AGN exhibit rapid, high amplitude stochastic flux variations across the
entire electromagnetic spectrum on timescales ranging from hours to years. The
cause of this variability is poorly understood. We present a Green's
Function-based method for using variability to (1) measure the time-scales on
which flux perturbations evolve and (2) characterize the driving flux
perturbations. We model the observed light curve of an AGN as a linear
differential equation driven by stochastic impulses. We analyze the light curve
of the Kepler AGN Zw 229-15 and find that the observed variability behavior can
be modeled as a damped harmonic oscillator perturbed by a colored noise
process. The model powerspectrum turns over on time-scale $385$~d. On shorter
time-scales, the log-powerspectrum slope varies between $2$ and $4$, explaining
the behavior noted by previous studies. We recover and identify both the
$5.6$~d and $67$~d timescales reported by previous work using the Green's
Function of the C-ARMA equation rather than by directly fitting the
powerspectrum of the light curve. These are the timescales on which flux
perturbations grow, and on which flux perturbations decay back to the
steady-state flux level respectively. We make the software package KALI used to
study light curves using our method available to the community.


title:
Nodal-line pairing with 1D-3D coupled Fermi surfaces: a model motivated
  by Cr-based superconductors

abstract:
  Motivated by the recent discovery of a new family of Chromium based
superconductors, we consider a two-band model, where a band of electrons
dispersing only in one direction interacts with a band of electrons dispersing
in all three directions. Strong $2k_f$ density fluctuations in the
one-dimensional band induces attractive interactions between the
three-dimensional electrons, which, in turn makes the system superconducting.
Solving the associated Eliashberg equations, we obtain a gap function which is
peaked at the "poles" of the three-dimensional Fermi sphere, and decreases
towards the "equator". When strong enough local repulsion is included, the gap
actually changes sign around the "equator" and nodal rings are formed. These
nodal rings manifest themselves in several experimentally observable
quantities, some of which resemble unconventional observations in the newly
discovered superconductors which motivated this work.


title:
Mott-insulator state of cold atoms in tilted optical lattices: doublon
  dynamics and multi-level Landau-Zener tunneling

abstract:
  We discuss the dynamical response of strongly interacting Bose atoms in an
adiabatically tilted optical lattice. The analysis is performed in terms of the
multi-level Landau-Zenner tunneling. Different regimes of tunneling are
identified and analytical expressions for the doublon number, which is the
quantity measured in laboratory experiments, are derived.


title:
Maximizing Science in the Era of LSST, Stars Study Group Report:
  Rotation and Magnetic Activity in the Galactic Field Population and in Open
  Star Clusters

abstract:
  This is the stars chapter of the Kavli workshop report, which resulted from
the community-based study of needed US OIR capabilities in the LSST era. The
full report, which will include this chapter, is anticipated to be available in
Fall 2016. See NOAO website (http://www.noao.edu/meetings/lsst-oir-study/) for
more details.


title: Topological Majorana Two-Channel Kondo Effect

abstract:
  A one-dimensional time-reversal-invariant topological superconductor hosts a
Majorana Kramers pair at each end, where time-reversal symmetry acts as a
supersymmetry that flips local fermion parity. We examine the transport anomaly
of such a superconductor, floating and tunnel-coupled to normal leads at its
two ends. We demonstrate the realization of a topologically-protected,
channel-symmetric, two-channel Kondo effect without fine-tuning. Whereas the
nonlocal teleportation vanishes, a lead present at one end telecontrols the
universal transport through the other end.


title: Giving top quark effective operators a boost

abstract:
  We investigate the prospects to systematically improve generic effective
field theory-based searches for new physics in the top sector during LHC run 2
as well as the high luminosity phase. In particular, we assess the benefits of
high momentum transfer final states on top EFT-fit as a function of systematic
uncertainties in comparison with sensitivity expected from fully-resolved
analyses focusing on $t\bar t$ production. We find that constraints are
typically driven by fully-resolved selections, while boosted top quarks can
serve to break degeneracies in the global fit. This demystifies and clarifies
the importance of high momentum transfer final states for global fits to new
interactions in the top sector from direct measurements.


title: The complex star cluster system of NGC 1316 (Fornax A)

abstract:
  This paper presents Gemini-$gri'$ high quality photometry for cluster
candidates in the field of NGC 1316 (Fornax A) as part of a study that also
includes GMOS spectroscopy. A preliminary discussion of the photometric data
indicates the presence of four stellar cluster populations with distinctive
features in terms of age, chemical abundance and spatial distribution. Two of
them seem to be the usually old (metal poor and metal rich) populations
typically found in elliptical galaxies. In turn, an intermediate-age (5 Gyr)
globular cluster population is the dominant component of the sample (as
reported by previous papers). We also find a younger cluster population with a
tentative age of $\approx$ 1 Gyr.


title:
Unique Room Temperature Light Emitting Diode Based on 2D Hybrid
  Organic-Inorganic Low Dimensional Perovskite Semiconductor

abstract:
  A Light Emitting Diode (LED) based on a two dimensional (2D) Hybrid
Organic-Inorganic Semiconductor (HOIS) functioning at room temperature is
demonstrated. LED is fabricated by depositing a layer of
(4-fluorophenethylamine-H)2PbI4 on an ITO substrate. It is the first time that
such a room temperature excitonic LED based on 2D lead iodide perovskite is
presented, as well as for its simplicity, low cost, ambient conditions
fabrication and functioning at 5-10V. The newly introduced class of 3D HOIS
perovskite LEDs, is now broadened with the implementation of the 2D HOIS. Novel
functionalities can be realized since it is now possible to access the hybrid's
2D semiconductor advantageous properties, such as increased excitonic binding
energy, oscillator strength and peak wavelength tunability.


title:
Density-dependent effective baryon-baryon interaction from chiral
  three-baryon forces

abstract:
  A density-dependent effective potential for the baryon-baryon interaction in
the presence of the (hyper)nuclear medium is constructed, based on the leading
(irreducible) three-baryon forces derived within SU(3) chiral effective field
theory. We evaluate the contributions from three classes: contact terms,
one-pion exchange and two-pion exchange. In the strangeness-zero sector we
recover the known result for the in-medium nucleon-nucleon interaction.
Explicit expressions for the Lambda-nucleon in-medium potential in (asymmetric)
nuclear matter are presented. Our results are suitable for implementation into
calculations of (hyper)nuclear matter. In order to estimate the low-energy
constants of the leading three-baryon forces we introduce the decuplet baryons
as explicit degrees of freedom and construct the relevant terms in the minimal
non-relativistic Lagrangian. With these, the constants are estimated through
decuplet saturation. Utilizing this approximation we provide numerical results
for the effect of the three-body force in symmetric nuclear matter and pure
neutron matter on the Lambda-nucleon interaction. A moderate repulsion that
increases with density is found in comparison to the free Lambda-nucleon
interaction.


title: Comments on "Isentropic Analysis of a Simulated Hurricane"

abstract:
  This paper describes Comments to the paper of Mrowiec et al. published in the
J. Atmos. Sci. in May 2016 (Vol 73, Issue 5, pages 1857-1870) and entitled
"Isentropic analysis of a simulated hurricane".
  It is explained that the plotting of isentropic surfaces (namely the
isentropes) requires a precise definition of the specific moist-air entropy,
and that most of existing "equivalent potential temperatures" lead to
inaccurate definitions of isentropes.
  It is shown that the use of the third law of thermodynamics leads to a
definition of the specific moist-air entropy (and of a corresponding potential
temperature) which allow the plotting of unambigous moist-air isentropes.
  Numerical applications are shown by using a numerical simulation of the
hurricane DUMILE.


title:
Vertex corrections for positive-definite spectral functions of simple
  metals

abstract:
  We present a systematic study of vertex corrections in the homogeneous
electron gas at metallic densities. The vertex diagrams are built using a
recently proposed positive-definite diagrammatic expansion for the spectral
function. The vertex function not only provides corrections to the well known
plasmon and particle-hole scatterings, but also gives rise to new physical
processes such as generation of two plasmon excitations or the decay of the
one-particle state into a two-particles-one-hole state. By an efficient Monte
Carlo momentum integration we are able to show that the additional scattering
channels are responsible for the bandwidth reduction observed in photoemission
experiments on bulk sodium, appearance of the secondary plasmon satellite below
the Fermi level, and a substantial redistribution of spectral weights. The
feasibility of the approach for first-principles band-structure calculations is
also discussed.


title: Levi's problem for complex homogeneous manifolds

abstract:
  Suppose $G$ is a connected complex Lie group and $H$ is a closed complex
subgroup. Then there exists a closed complex subgroup $J$ of $G$ containing $H$
such that the fibration $\pi:G/H \to G/J$ is the holomorphic reduction of
$G/H$, i.e., $G/J$ is holomorphically separable and ${\mathcal O}(G/H) \cong
\pi^*{\mathcal O}(G/J)$. In this paper we prove that if $G/H$ is pseudoconvex,
i.e., if $G/H$ admits a continuous plurisubharmonic exhaustion function, then
$G/J$ is Stein and $J/H$ has no non--constant holomorphic functions.


title: Defensive Distillation is Not Robust to Adversarial Examples

abstract:
  We show that defensive distillation is not secure: it is no more resistant to
targeted misclassification attacks than unprotected neural networks.


title: Room temperature polarization in the ferrimagnetic Ga2-xFexO3 ceramics

abstract:
  The effect of the Fe-Ga ratio on the magnetic and electric properties of the
multiferroic Ga2-xFexO3 compound has been studied in order to determine the
composition range exhibiting magnetic and electric orders coexistence and their
critical temperatures. A magnetoelectric phase diagram, showing the evolution
of both the Neel magnetic ordering temperature and the electric ordering
temperature, versus the iron content has been established for x values between
0.9 and 1.4. While the ferrimagnetic Neel temperature increases with the iron
content, the electric ordering temperature shows an opposite trend. The
electric polarization has been found to exist far above room temperature for
the x value of 1.1 composition which shows the highest observed electric
ordering temperature of approx. 580K. The compounds with x values of 1.3 and
1.4 are ferrimagnetic-electric relaxors with both properties coexisting at room
temperature.


title: Subwavelength Mode Profile Customisation Using Functional Materials

abstract:
  An ability to completely customise the mode profile in an electromagnetic
waveguide would be a useful ability. Currently, the transverse mode profile in
a waveguide might be varied, but this is usually a side effect of design
constraints, or for control of dispersion. In contrast, here we show how to
control the longitudinal (propagation direction) mode profile on a
sub-wavelength scale, but without the need for active solutions such as
synthesizing the shape by combining multiple Fourier harmonics. This is done by
means of a customised permittivity variation that can be calculated either
directly from the desired mode profile, or as inspired by e.g. the range of
shapes generated by the Mathieu functions. For applications such as charged
particle beam dynamics, requiring field profile shaping in free space, we show
that it is possible to achieve this despite the need to cut a channel through
the medium.


title: Synchrotron contribution to photon emission from quark-gluon plasma

abstract:
  We study the influence of the magnetic field on the photon emission from the
quark-gluon plasma created in $AA$ collisions. We find that even for very
optimistic assumption on the magnitude of the magnetic field for noncentral
$AA$ collisions the effect of magnetic field is very small.


title: Neural Semantic Encoders

abstract:
  We present a memory augmented neural network for natural language
understanding: Neural Semantic Encoders. NSE is equipped with a novel memory
update rule and has a variable sized encoding memory that evolves over time and
maintains the understanding of input sequences through read}, compose and write
operations. NSE can also access multiple and shared memories. In this paper, we
demonstrated the effectiveness and the flexibility of NSE on five different
natural language tasks: natural language inference, question answering,
sentence classification, document sentiment analysis and machine translation
where NSE achieved state-of-the-art performance when evaluated on publically
available benchmarks. For example, our shared-memory model showed an
encouraging result on neural machine translation, improving an attention-based
baseline by approximately 1.0 BLEU.


title:
Study of velocity centroids based on the theory of fluctuations in
  position-position-velocity space

abstract:
  We study possibility of obtaining velocity spectra by studying turbulence in
an optically thick medium using velocity centroids (VCs).We find that the
regime of universal, i.e. independent of underlying turbulence statistics,
fluctuations discovered originally within the velocity channel analysis (VCA)
carries over to the statistics of VCs. In other words, for large absorptions
the VC lose their ability to reflect the spectra of turbulence. Combining our
present study with the earlier studies of centroids in Esquivel & Lazarian, we
conclude that centroids are applicable for studies subsonic/transsonic
turbulence for the range of scales that is limited by the absorption effects.
We also consider VCs based on absorption lines and define the range of their
applicability. We address the problem of analytical description of spectra and
anisotropies of fluctuations that are available through studies using VC. We
obtain spectra and anisotropy of VC fluctuations arising from Alfv\'en, slow
and fast modes that constitute the compressible MHD cascade to address the
issue of anisotropy of VC statistics, and show how the VC anisotropy can be
used to find the media magnetization as well as to identify and separate
contributions from Alfv\'en, slow and fast modes. Our study demonstrates that
VCs are complementary to the tools provided by the VCA. In order to study
turbulent volume for which the resolution of single dish telescopes is
insufficient, we demonstrate how the studies of anisotropy can be performed
using interferometers.


title: Spinon excitations in the spin-1 XXZ chain and hidden supersymmetry

abstract:
  We study spinon excitations of the integrable spin-1 (Fateev-Zamolodchikov;
FZ) chain and their relation to the hidden supersymmetry. Using the notion of
the supercharges earlier introduced to the spin chains, which change the system
length by one, we found that they nontrivially act on one of two kinds of the
degrees of freedom for the FZ chain. Their actions were obtained to be the same
as those of the supercharges defined on the supersymmetric sine-Gordon model,
the low-energy effective field theory of the FZ chain. Moreover, we construct
the eigenstates which are invariant under the supersymmetric Hamiltonian given
as the anti-commutator of the supercharges.


title:
Understanding Citizen Reactions and Ebola-Related Information
  Propagation on Social Media

abstract:
  In severe outbreaks such as Ebola, bird flu and SARS, people share news, and
their thoughts and responses regarding the outbreaks on social media.
Understanding how people perceive the severe outbreaks, what their responses
are, and what factors affect these responses become important. In this paper,
we conduct a comprehensive study of understanding and mining the spread of
Ebola-related information on social media. In particular, we (i) conduct a
large-scale data-driven analysis of geotagged social media messages to
understand citizen reactions regarding Ebola; (ii) build information
propagation models which measure locality of information; and (iii) analyze
spatial, temporal and social properties of Ebola-related information. Our work
provides new insights into Ebola outbreak by understanding citizen reactions
and topic-based information propagation, as well as providing a foundation for
analysis and response of future public health crises.


title:
Fast-slow partially hyperbolic systems versus Freidlin-Wentzell random
  systems

abstract:
  We consider a simple class of fast-slow partially hyperbolic dynamical
systems and show that the (properly rescaled) behaviour of the slow variable is
very close to a Friedlin--Wentzell type random system for times that are rather
long, but much shorter than the metastability scale. Also, we show the
possibility of a "sink" with all the Lyapunov exponents positive, a phenomenon
that turns out to be related to the lack of absolutely continuity of the
central foliation.


title:
Learning Repository Adaptibility in an Agent-Based University
  Environment

abstract:
  Automated e-Learning Systems (AeLS) are fundamental to contemporary
educational concepts worldwide. It has become a standard not only in support to
the formal curriculum, but containing social platform capabilities,
gamification elements and functionalities fostering communities of experts,
also for faster knowledge dissemination. Additionally, AeLSs support internal
communications and customizable analytics and methodologies to quickly identify
learning performance, which in turn can be used as feedback to implement
adaptability in tailoring the content management to meet specific individual
needs. The volume of fast growing AeLS content of supplement material and
exchanged communication combined with the already huge material archived in the
university libraries is enormous and needs sophisticated managing through
electronic repositories. Such integration of content management systems (CMS)
present challenges which can be solved optimally with the use of distributed
management implemented through agent-based systems. This paper depicts a
successful implementation of an Integrated Intelligent Agent Based University
Information System (IABUIS).


title: Pseudomagnetic fields for sound at the nanoscale

abstract:
  There is a growing effort in creating chiral transport of sound waves.
However, most approaches so far are confined to the macroscopic scale. Here, we
propose a new approach suitable to the nanoscale which is based on
pseudomagnetic fields. These fields are the analogon for sound of the
pseudomagnetic field for electrons in strained graphene. In our proposal, they
are created by simple geometrical modifications of an existing and
experimentally proven phononic crystal design, the snowflake crystal. This
platform is robust, scalable, and well-suited for a variety of excitation and
readout mechanisms, among them optomechanical approaches.


title: Decidability of Non-Interactive Simulation of Joint Distributions

abstract:
  We present decidability results for a sub-class of "non-interactive"
simulation problems, a well-studied class of problems in information theory. A
non-interactive simulation problem is specified by two distributions $P(x,y)$
and $Q(u,v)$: The goal is to determine if two players, Alice and Bob, that
observe sequences $X^n$ and $Y^n$ respectively where $\{(X_i, Y_i)\}_{i=1}^n$
are drawn i.i.d. from $P(x,y)$ can generate pairs $U$ and $V$ respectively
(without communicating with each other) with a joint distribution that is
arbitrarily close in total variation to $Q(u,v)$. Even when $P$ and $Q$ are
extremely simple: e.g., $P$ is uniform on the triples $\{(0,0), (0,1), (1,0)\}$
and $Q$ is a "doubly symmetric binary source", i.e., $U$ and $V$ are uniform
$\pm 1$ variables with correlation say $0.49$, it is open if $P$ can simulate
$Q$.
  In this work, we show that whenever $P$ is a distribution on a finite domain
and $Q$ is a $2 \times 2$ distribution, then the non-interactive simulation
problem is decidable: specifically, given $\delta > 0$ the algorithm runs in
time bounded by some function of $P$ and $\delta$ and either gives a
non-interactive simulation protocol that is $\delta$-close to $Q$ or asserts
that no protocol gets $O(\delta)$-close to $Q$. The main challenge to such a
result is determining explicit (computable) convergence bounds on the number
$n$ of samples that need to be drawn from $P(x,y)$ to get $\delta$-close to
$Q$. We invoke contemporary results from the analysis of Boolean functions such
as the invariance principle and a regularity lemma to obtain such explicit
bounds.


title:
La derivada en varias variables como analog\'ia formal de su hom\'onima
  escalar

abstract:
  Some formal analogies between the Differential Calculus in One Variable and
the Differential Calculus in Several Variables are presented. It is studied and
introduced the derivability of functions at several variables from the single
variable conceptual analogous. This is obtained from exploring the dynamic
image of limit of a family of slopes of secants planes to the graphic of a
bivariate function.


title: Random-Key Cuckoo Search for the Travelling Salesman Problem

abstract:
  Combinatorial optimization problems are typically NP-hard, and thus very
challenging to solve. In this paper, we present the random key cuckoo search
(RKCS) algorithm for solving the famous Travelling Salesman Problem (TSP). We
used a simplified random-key encoding scheme to pass from a continuous space
(real numbers) to a combinatorial space. We also consider the displacement of a
solution in both spaces using Levy flights. The performance of the proposed
RKCS is tested against a set of benchmarks of symmetric TSP from the well-known
TSPLIB library. The results of the tests show that RKCS is superior to some
other metaheuristic algorithms.


title:
A spectroscopic study of blue supergiant stars in the Sculptor galaxy
  NGC 55: chemical evolution and distance

abstract:
  Low resolution (4.5 to 5 Angstroem) spectra of 58 blue supergiant stars
distributed over the disk of the Magellanic spiral galaxy NGC 55 in the
Sculptor group are analyzed by means of non-LTE techniques to determine stellar
temperatures, gravities and metallicities (from iron peak and alpha-elements).
A metallicity gradient of -0.22 +/- 0.06$ dex/R_25 is detected. The central
metallicity on a logarithmic scale relative to the Sun is [Z] = -0.37 +\- 0.03.
A chemical evolution model using the observed distribution of stellar and
interstellar medium gas mass column densities reproduces the observed
metallicity distribution well and reveals a recent history of strong galactic
mass accretion and wind outflows with accretion and mass-loss rates of the
order of the star formation rate. There is an indication of spatial
inhomogeneity in metallicity. In addition, the relatively high central
metallicity of the disk confirms that two extra-planar metal poor HII regions
detected in previous work 1.13 to 2.22 kpc above the galactic plane are ionized
by massive stars formed in-situ outside the disk. For a sub-sample of
supergiants, for which Hubble Space Telescope photometry is available, the
flux-weighted gravity--luminosity relationship is used to determine a distance
modulus of 26.85 +\- 0.10 mag.


title: Time evolution of localized states in Lieb lattices

abstract:
  We study the slow time evolution of localized states of the open-boundary
Lieb lattice when a magnetic flux is applied perpendicularly to the lattice and
increased linearly in time. In this system, Dirac cones periodically disappear,
reappear and touch the flat band as the flux increases. We show that the slow
time evolution of a localized state in this system is analogous to that of a
zero-energy state in a three-level system whose energy levels intersect
periodically and that this evolution can be mapped into a classical precession
motion with a precession axis that rotates as times evolves. Beginning with a
localized state of the Lieb lattice, as the magnetic flux is increased linearly
and slowly, the evolving state precesses around a state with a small itinerant
component and the amplitude of its localized component oscillates around a
constant value (below but close to 1), except at multiples of the flux quantum
where it may vary sharply. This behavior reflects the existence of an electric
field (generated by the time-dependent magnetic field) which breaks the C4
symmetry of the constant flux Hamiltonian.


title: Closure properties of classes of multiple testing procedures

abstract:
  Statistical discoveries are often obtained through multiple hypothesis
testing. A variety of procedures exists to evaluate multiple hypotheses, for
instance the ones of Benjamini-Hochberg, Bonferroni, Holm or Sidak. We are
particularly interested in multiple testing procedures with two desired
properties: (solely) monotonic and well-behaved procedures. This article
investigates to which extent the classes of (monotonic or well-behaved)
multiple testing procedures, in particular the subclasses of so-called step-up
and step-down procedures, are closed under basic set operations, specifically
the union, intersection, difference and the complement of sets of rejected or
non-rejected hypotheses. The present article proves two main results: First,
taking the union or intersection of arbitrary (monotonic or well-behaved)
multiple testing procedures results in new procedures which are monotonic but
not well-behaved, whereas the complement or difference generally preserves
neither property. Second, the two classes of (solely monotonic or well-behaved)
step-up and step-down procedures are closed under taking the union or
intersection, but not the complement or difference.


title: Molecular outflows in starburst nuclei

abstract:
  Recent observations have detected molecular outflows in a few nearby
starburst nuclei. We discuss the physical processes at work in such an
environment in order to outline a scenario that can explain the observed
parameters of the phenomenon, such as the molecular mass, speed and size of the
outflows. We show that outflows triggered by OB associations, with $N_{OB}\ge
10^5$ (corresponding to a star formation rate (SFR)$\ge 1$ M$_{\odot}$
yr$^{-1}$ in the nuclear region), in a stratified disk with mid-plane density
$n_0\sim 200\hbox{--}1000$ cm$^{-3}$ and scale height $z_0\ge 200 (n_0/10^2 \,
{\rm cm}^{-3})^{-3/5}$ pc, can form molecules in a cool dense and expanding
shell. The associated molecular mass is $\ge 10^7$ M$_\odot$ at a distance of a
few hundred pc, with a speed of several tens of km s$^{-1}$. We show that a SFR
surface density of $10 \le \Sigma_{SFR} \le 50$ M$_\odot$ yr$^{-1}$ kpc$^{-2}$
favours the production of molecular outflows, consistent with observed values.


title: The Finslerian wormhole models

abstract:
  We present models of wormhole under the Finslerian structure of spacetime.
This is a sequel of our previous work (Eur Phys J 75:564, 2015) where we
constructed a toy model for compact stars based on the Finslerian spacetime
geometry. In the present investigation, a wide variety of solutions are
obtained that explore wormhole geometry by considering different choices for
the form function and energy density. The solutions, like the previous work,
are revealed to be physically interesting and viable models for the explanation
of wormholes as far as the background theory and literature are concerned.


title:
Performance Comparison of Dual Connectivity and Hard Handover for LTE-5G
  Tight Integration in mmWave Cellular Networks

abstract:
  MmWave communications are expected to play a major role in the Fifth
generation of mobile networks. They offer a potential multi-gigabit throughput
and an ultra-low radio latency, but at the same time suffer from high isotropic
pathloss, and a coverage area much smaller than the one of LTE macrocells. In
order to address these issues, highly directional beamforming and a very
high-density deployment of mmWave base stations were proposed. This Thesis aims
to improve the reliability and performance of the 5G network by studying its
tight and seamless integration with the current LTE cellular network. In
particular, the LTE base stations can provide a coverage layer for 5G mobile
terminals, because they operate on microWave frequencies, which are less
sensitive to blockage and have a lower pathloss. This document is a copy of the
Master's Thesis carried out by Mr. Michele Polese under the supervision of Dr.
Marco Mezzavilla and Prof. Michele Zorzi. It will propose an LTE-5G tight
integration architecture, based on mobile terminals' dual connectivity to LTE
and 5G radio access networks, and will evaluate which are the new network
procedures that will be needed to support it. Moreover, this new architecture
will be implemented in the ns-3 simulator, and a thorough simulation campaign
will be conducted in order to evaluate its performance, with respect to the
baseline of handover between LTE and 5G.


title: Random projections of random manifolds

abstract:
  Interesting data often concentrate on low dimensional smooth manifolds inside
a high dimensional ambient space. Random projections are a simple, powerful
tool for dimensionality reduction of such data. Previous works have studied
bounds on how many projections are needed to accurately preserve the geometry
of these manifolds, given their intrinsic dimensionality, volume and curvature.
However, such works employ definitions of volume and curvature that are
inherently difficult to compute. Therefore such theory cannot be easily tested
against numerical simulations to understand the tightness of the proven bounds.
We instead study typical distortions arising in random projections of an
ensemble of smooth Gaussian random manifolds. We find explicitly computable,
approximate theoretical bounds on the number of projections required to
accurately preserve the geometry of these manifolds. Our bounds, while
approximate, can only be violated with a probability that is exponentially
small in the ambient dimension, and therefore they hold with high probability
in cases of practical interest. Moreover, unlike previous work, we test our
theoretical bounds against numerical experiments on the actual geometric
distortions that typically occur for random projections of random smooth
manifolds. We find our bounds are tighter than previous results by several
orders of magnitude.


title: Convexity and Order in Probabilistic Call-by-Name FPC

abstract:
  Kegelspitzen are mathematical structures coined by Keimel and Plotkin, in
order to encompass the structure of a convex set and the structure of a dcpo.
In this paper, we ask ourselves what are Kegelspitzen the model of. We adopt a
categorical viewpoint and show that Kegelspitzen model stochastic matrices onto
a category of domains. Consequently, Kegelspitzen form a denotational model of
pPCF, an abstract functional programming language for probabilistic computing.
We conclude the present work with a discussion of the interpretation of
(probabilistic) recursive types, which are types for entities which might
contain other entities of the same type, such as lists and trees.


title: Unequal Error Protection in Coded Slotted ALOHA

abstract:
  We analyze the performance of coded slotted ALOHA systems for a scenario
where users have different error protection requirements and correspondingly
can be divided into user classes. The main goal is to design the system so that
the requirements for each class are satisfied. To that end, we derive
analytical error floor approximations of the packet loss rate for each class in
the finite frame length regime, as well as the density evolution in the
asymptotic case. Based on this analysis, we propose a heuristic approach for
the optimization of the degree distributions to provide the required unequal
error protection. In addition, we analyze the decoding delay for users in
different classes and show that better protected users experience a smaller
average decoding delay.


title: Towards Stochastically Optimizing Data Computing Flows

abstract:
  With rapid growth in the amount of unstructured data produced by
memory-intensive applications, large scale data analytics has recently
attracted increasing interest. Processing, managing and analyzing this huge
amount of data poses several challenges in cloud and data center computing
domain. Especially, conventional frameworks for distributed data analytics are
based on the assumption of homogeneity and non-stochastic distribution of
different data-processing nodes. The paper argues the fundamental limiting
factors for scaling big data computation. It is shown that as the number of
series and parallel computing servers increase, the tail (mean and variance) of
the job execution time increase. We will first propose a model to predict the
response time of highly distributed processing tasks and then propose a new
practical computational algorithm to optimize the response time.


title:
Effects of Competition and Cooperation Interaction between Agents on
  Networks in Presence of a "Market Capacity"

abstract:
  A network effect is introduced taking into account competition, cooperation
and mixed-type interaction amongst agents along a generalized
Verhulst-Lotka-Volterra model. It is also argued that the presence of a market
capacity enforces an indubious limit on the agent's size growth. The state
stability of triadic agents, i.e., the most basic network plaquette, is
investigated analytically for possible scenarios, through a fixed point
analysis. It is discovered that: (i) \market" demand is only satisfied for full
competition when one agent monopolizes the market; (ii) growth of agent size is
encouraged in full cooperation; (iii) collaboration amongst agents to compete
against one single agent may result in the disappearance of this single agent
out of the market, and (iv) cooperating with two rivals may become a growth
strategy for an intelligent agent.


title: The Decision Tree Complexity for $k$-SUM is at most Nearly Quadratic

abstract:
  Following a recent improvement of Cardinal et al. on the complexity of a
linear decision tree for $k$-SUM, resulting in $O(n^3 \log^3{n})$ linear
queries, we present a further improvement to $O(n^2 \log^2{n})$ such queries.


title:
Strain induced topological phase transition at zigzag edges of monolayer
  transition-metal dichalcogenides

abstract:
  The effect of strain in zigzag ribbons of monolayer transition-metal
dichalcogenides with induced superconductivity is studied using a minimal
3-band tight-binding model. The unstrained system shows a topological phase
with Majorana zero modes localized at the boundaries of the one-dimensional
(1D) zigzag edges. By direct inspection of the spectrum and wave functions we
examine the evolution of the topological phase as an in-plane, uniaxial
deformation is imposed. It is found that strain shifts the energy of 1D edge
states, thus causing a topological phase transition which eliminates the
Majorana modes. For realistic parameter values, we show that the effect of
strain can be changed from completely destructive -- in which case a small
built in strain is enough to destroy the topological phase -- to a situation
where strain becomes an effective tuning parameter which can be used to
manipulate Majorana zero modes. These two regimes are accessible by increasing
the value of the applied Zeeman field within realistic values. We also study
how strain effects are affected by the chemical potential, showing in
particular how unwanted effects can be minimized. Finally, as a cross-check of
the obtained results, we reveal the connection between 1D Majorana zero modes
in the zigzag edge and the multi-band Berry phase, which serves as a
topological invariant of this system.