title:
Carbon and Oxygen Abundances in the Hot Jupiter Exoplanet Host Star
  XO-2N and its Binary Companion

abstract:
  With the aim of connecting the compositions of stars and planets, we present
the abundances of carbon and oxygen, as well as iron and nickel, for the
transiting exoplanet host star XO-2N and its wide-separation binary companion
XO-2S. Stellar parameters are derived from high-resolution,
high-signal-to-noise spectra, and the two stars are found to be similar in
their Teff, log g, iron ([Fe/H]), nickel ([Ni/H]) abundances. Their carbon
([C/H]) and oxygen ([O/H]) abundances also overlap within errors, although
XO-2N may be slightly more C-rich and O-rich than XO-2S. The C/O ratios of both
stars (~0.60+/-0.20) may also be somewhat larger than solar (C/O~0.50). The
XO-2 system has a transiting hot Jupiter orbiting one binary component but not
the other, allowing us to probe the potential effects planet formation might
have on the host star composition. Additionally, with multiple observations of
its atmosphere the transiting exoplanet XO-2b lends itself to compositional
analysis, which can be compared to the natal chemical environment established
by our binary star elemental abundances. This work sets the stage for
determining how similar/different exoplanet and host star compositions are, and
the implications for planet formation, by discussing the C/O ratio measurements
in the unique environment of a visual binary system with one star hosting a
transiting hot Jupiter.


title: SDSS J0025-10 at z=0.30: a (U)LIRG to optical QSO transition candidate

abstract:
  We have characterized the amount, spatial distribution and kinematics of the
molecular gas in the merging, double nucleus type 2 quasar SDSS J0025-10 at
z=0.30 using the CO(1-0) transition, based on data obtained with ATCA. This is
one of the scarce examples of quasar host galaxies where the CO emission has
been resolved spatially at any redshift. We infer a molecular gas mass M(H2) =
(6 +/- 1) x 1e9 Msun, which is distributed in two main reservoirs separated by
~9 kpc. ~60% of the gas is in the central region, associated with the QSO
nucleus and/or the intermediate region between the two nuclei. The other 40% is
associated with the northern tidal tail and is therefore unsettled.
  With its high infrared luminosity L(IR) = (1.1 +/- 0.3) x 1e12 Lsun, SDSS
J0025-10 is an analogue of local luminous LIRGs and ULIRGs. On the other hand,
the clear evidence for an ongoing major merger of two gas rich progenitors, the
high L(IR) dominated by a starburst, the massive reservoir of molecular gas
with a large fraction still unsettled, and the quasar activity are all
properties consistent with a transition phase in the (U)LIRG-optical QSO
evolutionary scenario. We propose that we are observing the system during a
particular transient phase, prior to more advanced mergers where the nuclei
have already coalesced.
  We argue that a fraction of the molecular gas reservoir is associated with a
tidal dwarf galaxy identified in the optical HST image at the tip of the
northern tidal tail. The formation of such structures is predicted by
simulations of colliding galaxies.


title: Tidal disruption of a super-Jupiter by a massive black hole

abstract:
  Aims: A strong, hard X-ray flare was discovered (IGR J12580+0134) by INTEGRAL
in 2011, and is associated to NGC 4845, a Seyfert 2 galaxy never detected at
high-energy previously. To understand what happened we observed this event in
the X-ray band on several occasions. Methods: Follow-up observations with
XMM-Newton, Swift, and MAXI are presented together with the INTEGRAL data. Long
and short term variability are analysed and the event wide band spectral shape
modelled. Results: The spectrum of the source can be described with an absorbed
(N_H ~ 7x10^22 cm^{-2}) power law (\Gamma \simeq 2.2), characteristic of an
accreting source, plus a soft X-ray excess, likely to be of diffuse nature. The
hard X-ray flux increased to maximum in a few weeks and decreased over a year,
with the evolution expected for a tidal disruption event. The fast variations
observed near the flare maximum allowed us to estimate the mass of the central
black hole in NGC 4845 as ~ 3x10^5 Msun. The observed flare corresponds to the
disruption of about 10% of an object with a mass of 14-30 Jupiter. The hard
X-ray emission should come from a corona forming around the accretion flow
close to the black hole. This is the first tidal event where such a corona has
been observed.


title: Frameworks with forced symmetry I: Reflections and rotations

abstract:
  We give a combinatorial characterization of generic frameworks that are
minimally rigid under the additional constraint of maintaining symmetry with
respect to a finite order rotation or a reflection. To establish these results
we develop a new technique for deriving linear representations of sparsity
matroids on colored graphs and extend the direction network method of proving
rigidity characterizations to handle reflections.


title:
Efficiency characterization of a large neuronal network: a causal
  information approach

abstract:
  When inhibitory neurons constitute about 40% of neurons they could have an
important antinociceptive role, as they would easily regulate the level of
activity of other neurons. We consider a simple network of cortical spiking
neurons with axonal conduction delays and spike timing dependent plasticity,
representative of a cortical column or hypercolumn with large proportion of
inhibitory neurons. Each neuron fires following a Hodgkin-Huxley like dynamics
and it is interconnected randomly to other neurons. The network dynamics is
investigated estimating Bandt and Pompe probability distribution function
associated to the interspike intervals and taking different degrees of
inter-connectivity across neurons. More specifically we take into account the
fine temporal ``structures'' of the complex neuronal signals not just by using
the probability distributions associated to the inter spike intervals, but
instead considering much more subtle measures accounting for their causal
information: the Shannon permutation entropy, Fisher permutation information
and permutation statistical complexity. This allows us to investigate how the
information of the system might saturate to a finite value as the degree of
inter-connectivity across neurons grows, inferring the emergent dynamical
properties of the system.


title: AGN feedback in clusters: shock and sound heating

abstract:
  Observations support the view that feedback, in the form of radio outbursts
from active nuclei in central galaxies, prevents catastrophic cooling of gas
and rapid star formation in many groups and clusters of galaxies. Variations in
jet power drive a succession of weak shocks that can heat regions close to the
active galactic nuclei (AGN). On larger scales, shocks fade into sound waves.
The Braginskii viscosity determines a well-defined sound damping rate in the
weakly magnetized intracluster medium (ICM) that can provide sufficient heating
on larger scales. It is argued that weak shocks and sound dissipation are the
main means by which radio AGN heat the ICM, in which case, the power spectrum
of AGN outbursts plays a central role in AGN feedback.


title: An improved quasar detection method in EROS-2 and MACHO LMC datasets

abstract:
  We present a new classification method for quasar identification in the
EROS-2 and MACHO datasets based on a boosted version of Random Forest
classifier. We use a set of variability features including parameters of a
continuous auto regressive model. We prove that continuous auto regressive
parameters are very important discriminators in the classification process. We
create two training sets (one for EROS-2 and one for MACHO datasets) using
known quasars found in the LMC. Our model's accuracy in both EROS-2 and MACHO
training sets is about 90% precision and 86% recall, improving the state of the
art models accuracy in quasar detection. We apply the model on the complete,
including 28 million objects, EROS-2 and MACHO LMC datasets, finding 1160 and
2551 candidates respectively. To further validate our list of candidates, we
crossmatched our list with a previous 663 known strong candidates, getting 74%
of matches for MACHO and 40% in EROS-2. The main difference on matching level
is because EROS-2 is a slightly shallower survey which translates to
significantly lower signal-to-noise ratio lightcurves.


title:
Why the US Needs a Deep Domestic Research Facility: Owning rather than
  Renting the Education Benefits, Technology Advances, and Scientific
  Leadership of Underground Physics

abstract:
  I summarize the status of the Sanford Underground Research Facility in South
Dakota and present connections to Energy and Intensity Frontier that benefit
from the establishment of SURF and the staging of US-funded experiments in a
domestic facility.


title:
Algebraic Multilevel Preconditioning in Isogeometric Analysis:
  Construction and Numerical Studies

abstract:
  We present algebraic multilevel iteration (AMLI) methods for isogeometric
discretization of scalar second order elliptic problems. The construction of
coarse grid operators and hierarchical complementary operators are given.
Moreover, for a uniform mesh on a unit interval, the explicit representation of
B-spline basis functions for a fixed mesh size $h$ is given for $p=2,3,4$ and
for $C^{0}$- and $C^{p-1}$-continuity. The presented methods show $h$- and
(almost) $p$-independent convergence rates. Supporting numerical results for
convergence factor and iterations count for AMLI cycles ($V$-, linear $W$-,
nonlinear $W$-) are provided. Numerical tests are performed, in two-dimensions
on square domain and quarter annulus, and in three-dimensions on quarter thick
ring.


title: Symmetry breaking in de Sitter: a stochastic effective theory approach

abstract:
  We consider phase transitions on (eternal) de Sitter in an O(N) symmetric
scalar field theory. Making use of Starobinsky's stochastic inflation we prove
that deep infrared scalar modes cannot form a condensate -- and hence they see
an effective potential that allows no phase transition. We show that by proving
convexity of the effective potential that governs deep infrared field
fluctuations both at the origin as well as at arbitrary values of the field.
Next, we present numerical plots of the scalar field probability distribution
function (PDF) and the corresponding effective potential for several values of
the coupling constant at the asymptotic future timelike infinity of de Sitter.
For small field values the effective potential has an approximately quadratic
form, corresponding to a positive mass term, such that the corresponding PDF is
approximately Gaussian. However, the curvature of the effective potential shows
qualitatively different (typically much softer) behavior on the coupling
constant than that implied by the Starobinsky-Yokoyama procedure. For large
field values, the effective potential as expected reduces to the tree level
potential plus a positive correction that only weakly (logarithmically) depends
on the background field. Finally, we calculate the backreaction of fluctuations
on the background geometry and show that it is positive.


title: Brownian Motion and General Relativity

abstract:
  We construct a model of Brownian Motion on a pseudo-Riemannian manifold
associated with general relativity. There are two aspects of the problem: The
first is to define a sequence of stopping times associated with the Brownian
"kicks" or impulses. The second is to define the dynamics of the particle along
geodesics in between the Brownian kicks. When these two aspects are taken
together, we can associate various distributions with the motion. We will find
that the statistics of space-time events will obey a temperature dependent four
dimensional Gaussian distribution defined over the quaternions which locally
can be identified with Minkowski space. Analogously, the statistics of the
4-velocities will obey a kind of Maxwell-Juttner distribution. In contrast to
previous work, our processes are characterized by two independent proper time
variables defined with respect to the laboratory frame: a discrete one
corresponding to the stopping times when the impulses take place and a
continuous one corresponding to the geodesic motion in-between impulses. The
subsequent distributions are then solutions of partial differential equations
which contain derivatives with respect to both time variables.


title:
Free boundary regularity for fully nonlinear non-homogeneous two-phase
  problems

abstract:
  We prove that flat or Lipschitz free boundaries of two-phase free boundary
problems governed by fully nonlinear uniformly elliptic operators and with
non-zero right hand side are $C^{1,\gamma}$.


title:
Radiation field for Einstein vacuum equations with spacial dimension
  $n\geq 4$

abstract:
  In this paper, the radiation field is defined for solutions to Einstein
vacuum equations which are close to Minkowski space-time with spacial dimension
$n\geq 4$. The regularity properties and asymptotic behavior of those Einstein
vacuum solutions are established at the same time. In particular, the map from
Cauchy intial data to the radiation field is proved to be an isomorphism when
restricting to a small neighborhood of Minkowski data in suitable weighted
b-Sobolev spaces.


title:
Stellar Coronae, Solar Flares: a Detailed Comparison of sigma Gem, HR
  1099, and the Sun in High-resolution X-rays

abstract:
  Chandra HETG spectra of the coronally active binary stars sigma Gem and HR
1099 are among the highest fluence observations for such systems taken at high
spectral resolution in x-rays with this instrument. We compare their properties
to solar flare spectra obtained with the Russian CORONAS-F RESIK instrument at
similar resolution in an overlapping bandpass. We emphasize the comparisons of
the 3.3-6.1 A region from solar flare spectra to the corresponding sigma Gem
and HR 1099 spectra. We also model the the HETG spectra from 1.7-25 A to
determine coronal temperatures and elemental abundances. Sigma Gem is a single
lined coronally active long period binary which has a very hot corona. HR 1099
is a similar, but shorter period, double lined system. In the deep exposures we
study emission from some of the weaker species, such as K, Na, and Al, which
have the lowest first ionization potentials (FIP). The solar flare temperatures
reach ~20 MK, comparable to the sigma Gem and HR 1099 coronae. During the
Chandra exposures, sigma Gem was slowly decaying from a flare and its spectrum
is well characterized by a collisional ionization equilibrium plasma with a
broad temperature distribution ranging from 2-60 MK, peaking near 25 MK, but
with substantial emission from 50 MK plasma. We have detected K XVIII and Na XI
emission which allow us to set limits on their abundances. HR 1099 was also in
a flare state but had no detectable K XVIII. These measurements provide new
comparisons of solar and stellar coronal abundances, especially at the lowest
FIP values. The low FIP elements do not show enhancement in the stellar coronae
as they do in the Sun, except for K in sigma Gem. Sigma Gem and HR 1099 differ
in their emission measure distributions but have very similar elemental
abundances.


title: On the asymmetry of the relative entropy

abstract:
  The quantum relative entropy $S(\rho||\sigma)$ is a widely used dissimilarity
measure between quantum states, but it has the peculiarity of being asymmetric
in its arguments. We quantify the amount of asymmetry by providing a sharp
upper bound in terms of two parameters: the trace norm distance between the two
states, and the smallest of the smallest eigenvalues of both states. The bound
is essentially the asymmetry between two binary distributions governed by these
two parameters.


title: Nonassociativity, Malcev Algebras and String Theory

abstract:
  Nonassociative structures have appeared in the study of D-branes in curved
backgrounds. In recent work, string theory backgrounds involving three-form
fluxes, where such structures show up, have been studied in more detail. We
point out that under certain assumptions these nonassociative structures
coincide with nonassociative Malcev algebras which had appeared in the quantum
mechanics of systems with non-vanishing three-cocycles, such as a point
particle moving in the field of a magnetic charge. We generalize the
corresponding Malcev algebras to include electric as well as magnetic charges.
These structures find their classical counterpart in the theory of
Poisson-Malcev algebras and their generalizations. We also study their
connection to Stueckelberg's generalized Poisson brackets that do not obey the
Jacobi identity and point out that nonassociative string theory with a
fundamental length corresponds to a realization of his goal to find a
non-linear extension of quantum mechanics with a fundamental length. Similar
nonassociative structures are also known to appear in the cubic formulation of
closed string field theory in terms of open string fields, leading us to
conjecture a natural string-field theoretic generalization of the AdS/CFT-like
(holographic) duality.


title: Exact pairs of homogeneous zero divisors

abstract:
  Let S be a standard graded Artinian algebra over a field k. We identify
constraints on the Hilbert function of S which are imposed by the hypothesis
that S contains an exact pair of homogeneous zero divisors. As a consequence,
we prove that if S is a compressed level algebra, then S does not contain any
homogeneous zero divisors.


title: The FuturICT Education Accelerator

abstract:
  Education is a major force for economic and social wellbeing. Despite high
aspirations, education at all levels can be expensive and ineffective. Three
Grand Challenges are identified: (1) enable people to learn orders of magnitude
more effectively, (2) enable people to learn at orders of magnitude less cost,
and (3) demonstrate success by exemplary interdisciplinary education in complex
systems science. A ten year `man-on-the-moon' project is proposed in which
FuturICT's unique combination of Complexity, Social and Computing Sciences
could provide an urgently needed transdisciplinary language for making sense of
educational systems. In close dialogue with educational theory and practice,
and grounded in the emerging data science and learning analytics paradigms,
this will translate into practical tools (both analytical and computational)
for researchers, practitioners and leaders; generative principles for resilient
educational ecosystems; and innovation for radically scalable, yet
personalised, learner engagement and assessment. The proposed {\em Education
Accelerator} will serve as a `wind tunnel' for testing these ideas in the
context of real educational programmes, with an international virtual campus
delivering complex systems education exploiting the new understanding of
complex, social, computationally enhanced organisational structure developed
within FuturICT.


title:
An Efficient and Optimal Filter for Identifying Point Sources in
  Millimeter/Sub-Millimeter Wavelength Sky Maps

abstract:
  A new technique for reliably identifying point sources in
millimeter/sub-millimeter wavelength maps is presented. This method accounts
for the frequency dependence of noise in the Fourier domain as well as
non-uniformities in the coverage of a field. This optimal filter is an
improvement over commonly-used matched filters that ignore coverage gradients.
Treating noise variations in the Fourier domain as well as map space is
traditionally viewed as a computationally intensive problem. We show that the
penalty incurred in terms of computing time is quite small due to casting many
of the calculations in terms of FFTs and exploiting the absence of sharp
features in the noise spectra of observations. Practical aspects of
implementing the optimal filter are presented in the context of data from the
AzTEC bolometer camera. The advantages of using the new filter over the
standard matched filter are also addressed in terms of a typical AzTEC map.


title:
MESA and NuGrid Simulations of Classical Nova Outbursts and
  Nucleosynthesis

abstract:
  Classical novae are the results of surface thermonuclear explosions of
hydrogen accreted by white dwarfs (WDs) from their low-mass main-sequence or
red-giant binary companions. Chemical composition analysis of their ejecta
shows that nova outbursts occur on both carbon-oxygen (CO) and more massive
oxygen-neon (ONe) WDs, and that there is cross-boundary mixing between the
accreted envelope and underlying WD. We demonstrate that the state-of-the-art
stellar evolution code MESA and post-processing nucleosynthesis tools of NuGrid
can successfully be used for modeling of CO and ONe nova outbursts and
nucleosynthesis. The convective boundary mixing (CBM) in our 1D numerical
simulations is implemented using a diffusion coefficient that is exponentially
decreasing with a distance below the bottom of the convective envelope. We show
that this prescription produces maximum temperature evolution profiles and
nucleosynthesis yields in good agreement with those obtained using the commonly
adopted 1D nova model in which the CBM is mimicked by assuming that the
accreted envelope has been pre-mixed with WD's material. In a previous paper,
we have found that 3He can be produced in situ in solar-composition envelopes
accreted with slow rates (dM/dt < 1e-10 M_sun/yr) by cold (T_WD < 1d7 K) CO
WDs, and that convection is triggered by 3He burning before the nova outburst
in this case. Here, we confirm this result for ONe novae. Additionally, we find
that the interplay between the 3He production and destruction in the
solar-composition envelope accreted with an intermediate rate, e.g. dM/dt =
1e-10 M_sun/yr, by the 1.15 M_sun ONe WD with a relatively high initial central
temperature, e.g. T_WD = 15e6 K, leads to the formation of a thick radiative
buffer zone that separates the bottom of the convective envelope from the WD
surface.


title: Grand Symmetry, Spectral Action, and the Higgs mass

abstract:
  In the context of the spectral action and the noncommutative geometry
approach to the standard model, we build a model based on a larger symmetry.
With this "grand symmetry" it is natural to have the scalar field necessary to
obtain the Higgs mass in the vicinity of 126 GeV. This larger symmetry mixes
gauge and spin degrees of freedom without introducing extra fermions. Requiring
the noncommutative space to be an almost commutative geometry (i.e. the product
of manifold by a finite dimensional internal space) gives conditions for the
breaking of this grand symmetry to the standard model.


title: Nonthermal Emission from Star-Forming Galaxies

abstract:
  The detections of high-energy gamma-ray emission from the nearby starburst
galaxies M82 & NGC253, and other local group galaxies, broaden our knowledge of
star-driven nonthermal processes and phenomena in non-AGN star-forming
galaxies. We review basic aspects of the related processes and their modeling
in starburst galaxies. Since these processes involve both energetic electrons
and protons accelerated by SN shocks, their respective radiative yields can be
used to explore the SN-particle-radiation connection. Specifically, the
relation between SN activity, energetic particles, and their radiative yields,
is assessed through respective measures of the particle energy density in
several star-forming galaxies. The deduced energy densities range from O(0.1)
eV/cm^3 in very quiet environments to O(100) eV/cm^3 in regions with very high
star-formation rates.


title: Easy Holography

abstract:
  It is argued that the role of infinite dimensional asymptotic symmetry groups
in gravity theories are essential for a holographic description of gravity and
possibly to a resolution of the black hole information paradox. I present a
simple toy model in two dimensional hyperbolic/ anti-de Sitter (AdS) space and
describe, by very elementary considerations, how the asymptotic symmetry group
is responsible for the entropy area law. Similar results apply also in three
dimensional AdS space. The failure of the approach in higher dimensional AdS
spaces is explained and resolved by considering other asymptotically noncompact
homogeneous spaces.


title:
Extending the Electron Spin Coherence Time of Atomic Hydrogen by
  Dynamical Decoupling

abstract:
  We study the electron spin decoherence of encapsulated atomic hydrogen in
octasilsesquioxane cages induced by the 1H and 29Si nuclear spin bath. By
applying the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence we significantly
suppress the low-frequency noise due to nuclear spin flip-flops up to the point
where a maximum T2 = 56 us is observed. Moreover, dynamical decoupling with the
CPMG sequence reveals the existence of two sources of high-frequency noise:
first, a fluctuating magnetic field with the proton Larmor frequency,
equivalent to classical magnetic field noise imposed by the 1H nuclear spins of
the cage organic substituents, and second, decoherence due to entanglement
between the electron and the inner 29Si nuclear spin of the cage.


title: Top-K Product Design Based on Collaborative Tagging Data

abstract:
  The widespread use and popularity of collaborative content sites (e.g., IMDB,
Amazon, Yelp, etc.) has created rich resources for users to consult in order to
make purchasing decisions on various products such as movies, e-commerce
products, restaurants, etc. Products with desirable tags (e.g., modern,
reliable, etc.) have higher chances of being selected by prospective customers.
This creates an opportunity for product designers to design better products
that are likely to attract desirable tags when published. In this paper, we
investigate how to mine collaborative tagging data to decide the attribute
values of new products and to return the top-k products that are likely to
attract the maximum number of desirable tags when published. Given a training
set of existing products with their features and user-submitted tags, we first
build a Naive Bayes Classifier for each tag. We show that the problem of is
NP-complete even if simple Naive Bayes Classifiers are used for tag prediction.
We present a suite of algorithms for solving this problem: (a) an exact two
tier algorithm(based on top-k querying techniques), which performs much better
than the naive brute-force algorithm and works well for moderate problem
instances, and (b) a set of approximation algorithms for larger problem
instances: a novel polynomial-time approximation algorithm with provable error
bound and a practical hill-climbing heuristic. We conduct detailed experiments
on synthetic and real data crawled from the web to evaluate the efficiency and
quality of our proposed algorithms, as well as show how product designers can
benefit by leveraging collaborative tagging information.


title: Topics In Normal Bases Of Finite Fields

abstract:
  This is an introduction to the theory of normal bases of finite fields. The
first few chapters cover a wide range of topics on the theory of normal bases
of finite fields. Most standard definitions and results, including proofs are
given. The last few chapters cover the theory of guassian and period normal
bases of finite fields of low degrees. The last chapter presents the asymptotic
proofs of the existence of primitive polynomials of degree n with approximately
n/2 arbitrary coefficients, and primitive normal polynomials of arbitrary
traces.


title: Stroke-Based Cursive Character Recognition

abstract:
  Human eye can see and read what is written or displayed either in natural
handwriting or in printed format. The same work in case the machine does is
called handwriting recognition. Handwriting recognition can be broken down into
two categories: off-line and on-line. ...


title:
MIMO Communications over Multi-Mode Optical Fibers: Capacity Analysis
  and Input-Output Coupling Schemes

abstract:
  We consider multi-input multi-output (MIMO) communications over multi-mode
fibers (MMFs). Current MMF standards, such as OM3 and OM4, use fibers with core
radii of 50 \mu m, allowing hundreds of modes to propagate. Unfortunately, due
to physical and computational complexity limitations, we cannot couple and
detect hundreds of data streams into and out of the fiber. In order to
circumvent this issue, we present input-output coupling schemes that allow the
user to couple and extract a reasonable number of signals from a fiber with
many modes. This approach is particularly attractive as it is scalable; i.e.,
the fibers do not have to be replaced every time the number of transmitters or
receivers is increased, a phenomenon that is likely to happen in the near
future.
  We present a statistical channel model that incorporates intermodal
dispersion, chromatic dispersion, mode dependent losses, mode coupling, and
input-output coupling. We show that the statistics of the fiber's frequency
response are independent of frequency. This simplifies the computation of the
average Shannon capacity of the fiber. We also provide an input-output coupling
strategy that leads to an increase in the overall capacity. This strategy can
be used whenever channel state information (CSI) is available at the
transmitter. We show that the capacity of an Nt by Nt MIMO system over a fiber
with M>>Nt modes can approach the capacity of an Nt-mode fiber with no
mode-dependent losses. We finally present a statistical input-output coupling
model in order to quantify the loss in capacity when CSI is not available at
the transmitter. It turns out that the loss, relative to Nt-mode fibers, is
minimal (less than 0.5 dB) for a wide range of signal-to-noise ratios (SNRs)
and a reasonable range of MDLs.


title:
Reliability sensitivity analysis based on probability distribution
  perturbation with application to CO2 storage

abstract:
  The objective of reliability sensitivity analysis is to determine input
variables that mostly contribute to the variability of the failure probability.
In this paper, we study a recently introduced method for the reliability
sensitivity analysis based on a perturbation of the original probability
distribution of the input variables. The objective is to determine the most
influential input variables and to analyze their impact on the failure
probability. We propose a moment independent sensitivity measure that is based
on a perturbation of the original probability density independently for each
input variable. The variables providing the highest variation of the original
failure probability are settled to be more influential. These variables will
need a proper characterization in terms of uncertainty. The method is intended
to work in applications involving a computationally expensive simulation code
for evaluating the failure probability such as the CO2 storage risk analysis.
An application of the method to a synthetic CO2 storage case study is provided
together with some analytical examples


title: The two phase parabolic Signorini Problem

abstract:
  We study solutions to a variational equation that models heat control on the
boundary. This problem can be thought of as the two phase parabolic Signorini
problem. We show that when the solution has a sign on the boundary, the study
of the free boundary can be reduced to the study of the free boundary in the
parabolic Signorini problem. We show that locally there is always a sign on the
boundary; therefore, the optimal regularity of the solutions as well as the
study of the free boundary is reduced to the one phase parabolic Signorini
problem.


title:
Analytic Solutions for Navarro--Frenk--White Lens Models for Low
  Characteristic Convergences

abstract:
  The Navarro-Frenk-White (NFW) density profile is often used to model
gravitational lenses. For low values of the characteristic convergence
($\kappa_s \ll 1$) of this model - corresponding to galaxy and galaxy group
mass scales - a high numerical precision is required in order to accurately
compute several quantities in the strong lensing regime. An alternative for
fast and accurate computations is to derive analytic approximations in this
limit. In this work we obtain analytic solutions for several lensing quantities
for elliptical (ENFW) and pseudo-elliptical (PNFW) NFW lens models on the
typical scales where gravitational arcs are expected to be formed, in the
$\kappa_s \ll 1$ limit, establishing their domain of validity. We derive
analytic solutions for the convergence and shear for these models, obtaining
explicit expressions for the iso-convergence contours and constant distortion
curves (including the tangential critical curve). We also compute the
deformation cross section, which is given in closed form for the circular NFW
model and in terms of a one-dimensional integral for the elliptical ones. In
addition, we provide a simple expression for the ellipticity of the
iso-convergence contours of the pseudo-elliptical models and the connection of
characteristic convergences among the PNFW and ENFW models. We conclude that
the set of solutions derived here is generally accurate for $\kappa_s \lesssim
0.1$. For low ellipticities, values up to $\kappa_s \simeq 0.18$ are allowed.
On the other hand, the mapping between PNFW and the ENFW models is valid up to
$\kappa_s \simeq 0.4$. The solutions derived in this work can be used to speed
up numerical codes and ensure their accuracy in the low $\kappa_s$ regime,
including applications to arc statistics and other strong lensing observables.
(Abridged)


title: Cartan subgroups and generosity in $SL_2(\mathbb{Q}_p)$

abstract:
  We describe all Cartan subgroups of $SL_2(\mathbb{Q}_p)$. We show that the
Cartan subgroup consisting of all diagonal matrices is generous and it is the
only one up to conjugacy.


title:
Correlated Photon Pair Production by Spontaneous Parametric Down
  Conversion in Quasi-Phase-Matched AlGaAs superlattice Waveguides using a
  Continuous Wave Pump

abstract:
  We report on the demonstration of correlated photon pair generation in
quasi-phase-matched superlattice AlGaAs waveguides with a high
coincidence-to-accidental ratio (CAR); with a continuous (CW) pump, the
observed CAR (>100) is more than two order of magnitudes improvement over
previously reported spontaneous down conversion (SPDC) schemes in AlGaAs
waveguides with a pulsed pump.


title: Convex and subharmonic functions on graphs

abstract:
  We explore the relationship between convex and subharmonic functions on
discrete sets. Our principal concern is to determine the setting in which a
convex function is necessarily subharmonic. We initially consider the primary
notions of convexity on graphs and show that more structure is needed to
establish the desired result. To that end, we consider a notion of convexity
defined on lattice-like graphs generated by normed abelian groups. For this
class of graphs, we are able to prove that all convex functions are
subharmonic.


title: Umbral Vade Mecum

abstract:
  In recent years the umbral calculus has emerged from the shadows to provide
an elegant correspondence framework that automatically gives systematic
solutions of ubiquitous difference equations --- discretized versions of the
differential cornerstones appearing in most areas of physics and engineering
--- as maps of well-known continuous functions. This correspondence deftly
sidesteps the use of more traditional methods to solve these difference
equations. The umbral framework is discussed and illustrated here, with special
attention given to umbral counterparts of the Airy, Kummer, and Whittaker
equations, and to umbral maps of solitons for the Sine-Gordon, Korteweg--de
Vries, and Toda systems.


title:
Surface States of Topological Crystalline Insulators in IV-VI
  Semiconductors

abstract:
  Topological crystalline insulators (TCI) are new topological phases of matter
protected by crystal symmetry of solids. Recently, the first realization of TCI
has been predicted and observed in IV-VI semiconductor SnTe and related alloys
Pb_{1-x}Sn_{x}(Te, Se). By combining k.p theory and band structure calculation,
we present a unified approach to study topological surface states on various
crystal surfaces of TCI in IV-VI semiconductors. We explicitly derive k.p
Hamiltonian for topological surface states from electronic structure of the
bulk, thereby providing a microscopic understanding of bulk-boundary
correspondence in TCI. Depending on the surface orientation, we find two types
of surface states with qualitatively different properties. In particular, we
predict that (111) surface states consist of four Dirac cones centered at
time-reversal-invariant momenta {\Gamma} and M, while (110) surface states
consist of Dirac cones at non-time-reversal-invariant momenta, similar to
(001). Moreover, both (001) and (110) surface states exhibit a Lifshitz
transition as a function of Fermi energy, which is accompanied by a Van-Hove
singularity in density of states arising from saddle points in the band
structure.


title:
On Some New Hermite-Hadamard type inequalities for s-geometrically
  convex functions

abstract:
  In this paper, some new integral inequalities of Hermite-Hadamard type
related to the s-geometrically convex functions are established and some
applications to special means of positive real numbers are also given.


title:
Constant-Factor Optimization of Quantum Adders on 2D Quantum
  Architectures

abstract:
  Quantum arithmetic circuits have practical applications in various quantum
algorithms. In this paper, we address quantum addition on 2-dimensional
nearest-neighbor architectures based on the work presented by Choi and Van
Meter (JETC 2012). To this end, we propose new circuit structures for some
basic blocks in the adder, and reduce communication overhead by adding
concurrency to consecutive blocks and also by parallel execution of expensive
Toffoli gates. The proposed optimizations reduce total depth from $140\sqrt
n+k_1$ to $92\sqrt n+k_2$ for constants $k_1,k_2$ and affect the computation
fidelity considerably.


title: Extra-Dimensional Bi-Inflation

abstract:
  We study a solution to the Einstein field equations on an eight-dimensional
pseudo-Riemannian manifold (a spacetime of four space dimensions and four time
dimensions) that exhibits inflation of three of the four space dimensions and
deflation of three of the four time dimensions. Hubble parameters
$(\mathbb{H}_4, \mathbb{H}_8)$ exist for each of the unscaled dimensions
$(\textrm{time}x^4, \textrm{space}x^8)$. The scale factor for the three
ordinary space dimensions $(x^1, x^2, x^3)$ is $a = a(x^4, x^8)$, and during
inflation is functionally a product of exponentials $a = e^{\mathbb{H}_4\,
x^4\,/\,c} \; e^{\mathbb{H}_8\, x^8\,/\,c}$ of each Hubble parameter times its
respective unscaled coordinate ($c$ is the physical speed of gravitational
waves in vacuum in the observed universe). We investigate the conjecture that
every particle/field in our universe is carried along the $x^8$-axis in the
same way that it is carried along the $x^4$-axis, that is, in a manner that is
independent of its energy, and with no freedom to change either its rate of
passage along the $x^8$-axis or its location within the $x^8$-dimension. The
evolution of the particle/field through the unscaled dimensions $(x^4, x^8) \in
\mathbb{R}^{1,1}$ in our universe is entrapped and entrained by geometry. We
employ a line element of the form $ {ds}^2 = -|g_{4\,4}| \; {(c_4 \, d x^4)}^2
+ g_{8\,8} \; {(d x^8)}^2 \;+\;...$ to define a physical time $t = x^0$ through
the relation % $ |g_{t\,t}| \; {(c \, d t)}^2 = |g_{4\,4}| \; {(c_4 \, d
x^4)}^2 - g_{8\,8} \; {(d x^8)}^2 $. Here $c_4$ is a speed related parameter
(in this paper $g_{t\,t} = g_{4\,4} = -1 $). This model offers new insight into
physical time.


title: Role of three-nucleon forces and many-body processes in nuclear pairing

abstract:
  We present microscopic valence-shell calculations of pairing gaps in the
calcium isotopes, focusing on the role of three-nucleon (3N) forces and
many-body processes. In most cases, we find a reduction in pairing strength
when the leading chiral 3N forces are included, compared to results with
low-momentum two-nucleon (NN) interactions only. This is in agreement with a
recent energy density functional study. At the NN level, calculations that
include particle-particle and hole-hole ladder contributions lead to smaller
pairing gaps compared with experiment. When particle-hole contributions as well
as the normal-ordered one- and two-body parts of 3N forces are consistently
included to third order, we find reasonable agreement with experimental
three-point mass differences. This highlights the important role of 3N forces
and many-body processes for pairing in nuclei. Finally, we relate pairing gaps
to the evolution of nuclear structure in neutron-rich calcium isotopes and
study the predictions for the 2+ excitation energies, in particular for 54Ca.


title:
First identification and absolute magnitudes of the red clump stars in
  the Solar neighbourhood for WISE

abstract:
  We present the first determination of absolute magnitudes for the red clump
(RC) stars with the Wide-field Infrared Survey Explorer (WISE). We used
recently reduced parallaxes taken from the Hipparcos catalogue and identified
3889 RC stars with the WISE photometry in the Solar neighbourhood. Mode values
estimated from the distributions of absolute magnitudes and a colour of the RC
stars in WISE photometry are M_{W1}=-1.635(0.026), M_{W3}=-1.606(0.024) and
(W1-W3)_0=-0.028(0.001) mag. These values are consistent with those obtained
from the transformation formulae using 2MASS data. Distances of the RC stars
estimated by using their M_{W1} and M_{W3} absolute magnitudes are in agreement
with the ones calculated by the spectrophotometric method, as well. These WISE
absolute magnitudes can be used in astrophysical researches where distance
plays an important role.


title:
SMA Observations of Class 0 Protostars: A High-Angular Resolution Survey
  of Protostellar Binary Systems

abstract:
  We present high angular resolution 1.3 mm and 850 um dust continuum data
obtained with the Submillimeter Array toward 33 Class 0 protostars in nearby
clouds (distance < 500 pc), which represents so far the largest survey toward
protostellar binary/multiple systems. The median angular resolution in the
survey is 2.5 arcsec, while the median linear resolution is approximately 600
AU. Compact dust continuum emission is observed from all sources in the sample.
Twenty-one sources in the sample show signatures of binarity/multiplicity, with
separations ranging from 50 to 5000 AU. The numbers of singles, binaries,
triples, and quadruples in the sample are 12, 14, 5, and 2, respectively. The
derived multiplicity frequency (MF) and companion star fraction (CSF) for Class
0 protostars are 0.64+/-0.08 and 0.91+/-0.05, respectively, with no correction
for completeness. The derived MF and CSF in this survey are approximately two
times higher than the values found in the binary surveys toward Class I YSOs,
and approximately three (for MF) and four (for CSF) times larger than the
values found among MS stars, with a similar range of separations. Furthermore,
the observed fraction of high order multiple systems to binary systems in Class
0 protostars (0.50+/-0.09) is also larger than the fractions found in Class I
YSOs (0.31+/-0.07) and MS stars (< 0.2). These results suggest that binary
properties evolve as protostars evolve, as predicted by numerical simulations.
The distribution of separations for Class 0 protostellar binary systems shows a
general trend in which companion star fraction increases with decreasing
companion separation. We find that 67%+/-8% of the protobinary systems have
circumstellar mass ratios below 0.5, implying that unequal-mass systems are
preferred in the process of binary star formation. We suggest an empirical
sequential fragmentation picture for binary star formation.


title:
Modeling pre-biotic self-organization: The chemical dynamics of
  autocatalytic networks

abstract:
  In this thesis we present a mathematical model describing the population
dynamics of molecules in an artificial chemistry where large molecules can be
produced by successive ligation of pairs of smaller molecules. The chemistry
contains a large number of spontaneous reactions of which a small subset could
be catalyzed by molecules produced in the chemistry with varying catalytic
strengths. We show ACSs, if present in the catalytic network, can focus the
resources of the system into a sparse set of molecules. ACSs can produce a
bistability in the population dynamics and, in particular, steady states
wherein the ACS molecules dominate the population, i.e., have higher
concentrations compared to the rest of molecules in the chemistry (background).
In this thesis we attempt to address two main questions: First, under what
circumstances do molecules belonging to the ACSs dominate over the background,
and second, starting from an initial condition that does not contain good
catalysts, can a sparse set of large molecules (containing several tens or a
few hundred monomers) that are good catalysts arise and be maintained in the
system at concentrations significantly above the background? We show that if an
ACS catalyzed by large molecules contains within it (or partially overlaps
with) a smaller ACS catalyzed by smaller molecules (referred to as a `nested
ACS' structure), the catalytic strength required for the large ACS to dominate
comes down significantly. We show that when the network contains a cascade of
nested ACSs with the catalytic strengths of molecules increasing gradually with
their size, a sparse subset of molecules including some very large molecules
can come to dominate the system.


title: Complete control, direct observation and study of molecular super rotors

abstract:
  Extremely fast rotating molecules carrying significantly more energy in their
rotation than in any other degree of freedom are known as "super rotors". It
has been speculated that super rotors may exhibit a number of unique
properties. Theoretical studies showed that ultrafast molecular rotation may
change the character of molecular scattering from solid surfaces, alter
molecular trajectories in external fields, make super rotors stable against
collisions, and lead to the formation of gas vortices. New ways of molecular
cooling and selective chemical bond breaking by ultrafast spinning have been
suggested. Bringing a large number of molecules to fast, directional and
synchronous rotation is rather challenging. An efficient method of accelerating
molecular rotation with an "optical centrifuge" has been proposed and
successfully implemented, yet only indirect evidence of super rotors has been
reported to date. Here we demonstrate the first direct observation of molecular
super rotors and study their spectroscopic, dynamical and magneto-optical
properties. Using the centrifuge technique, we control the degree of rotational
excitation and detect molecular rotation with high spectral and temporal
resolution. Frequency-resolved detection enables us to map out the energy of
extreme rotation levels, two orders of magnitude above the room temperature
limit, and quantify the onset of the centrifugal distortion. Femtosecond time
resolution reveals highly coherent rotational dynamics with lower de-coherence
rates at higher values of the molecular angular momentum, and the increase of
the molecular moment of inertia due to the rotation-induced chemical bond
stretching. In the presence of an external magnetic field, ultrafast molecular
rotation is found to result in an optical birefringence of the molecular
ensemble.


title: A discrete model of energy-conserved wavefunction collapse

abstract:
  Energy nonconservation is a serious problem of dynamical collapse theories.
In this paper, we propose a discrete model of energy-conserved wavefunction
collapse. It is shown that the model is consistent with existing experiments
and our macroscopic experience.


title: The quantal algebra and abstract equations of motion

abstract:
  The quantal algebra combines classical and quantum mechanics into an abstract
structurally unified structure. The structure uses two products: one symmetric
and one anti-symmetric. The local structure of spacetime is contained in the
quantal algebra without having been postulated. We will introduce an abstract
derivation concept and generalize classical and quantum mechanics equations of
motion to abstract equations of motion in which the anti-symmetric product of
the quantal algebra plays a key role. We will express the defining identities
of the quantal algebra in terms of the abstract derivation. In this form the
first defining identity (the Jacobi identity) is analogous in form to the
Bianchi identity in general relativity which is one set of gravitational field
equations for the curvature tensor. The identity for the unit element is
equivalent to the important property that the metric is covariantly constant.
Similarly, the Jacobi identity is analogous in form to the homogeneous Maxwell
equations. The anti-symmetric product of the quantal algebra is reflected in
the antisymmetry of the electromagnetic tensor.


title: Analysis of Metal Cutting Acoustic Emissions by Time Series Models

abstract:
  We analyse some acoustic emission time series obtained from a lathe machining
process. Considering the dynamic evolution of the process we apply two classes
of well known stationary stochastic time series models. We apply a preliminary
root mean square (RMS) transformation followed by an ARMA analysis; results
thereof are mainly related to the description of the continuous part (plastic
deformation) of the signal. An analysis of acoustic emission, as some previous
works show, may also be performed with the scope of understanding the evolution
of the ageing process that causes the degradation of the working tools. Once
the importance of the discrete part of the acoustic emission signals (i.e.
isolated amplitude bursts) in the ageing process is understood, we apply a
stochastic analysis based on point processes waiting times between bursts and
to identify a parameter with which to characterise the wear level of the
working tool. A Weibull distribution seems to adequately describe the waiting
times distribution.


title: From SU(2) gauge theory to qubits on the fuzzy sphere

abstract:
  We consider a classical pure SU(2) gauge theory, and make an ansatz, which
separates the space-temporal degrees of freedom from the internal ones. This
ansatz is gauge-invariant but not Lorentz invariant. In a limit case of the
ansatz, obtained through a contraction map, and corresponding to a vacuum
solution, the SU(2) gauge field reduces to an operator, which is the product of
the generator of a global U(1) group times a Pauli matrix. We give a
geometrical interpretation of the ansatz and of the contraction map in the
framework of principal fiber bundles. Then, we identify the internal degrees of
freedom of the gauge field with the non-commutative coordinates of the fuzzy
sphere in the fundamental representation and obtain a one qubit state.


title:
A study of AGN and supernova feedback in simulations of isolated and
  merging disc galaxies

abstract:
  We perform high resolution N-body+SPH simulations of isolated Milky-Way-like
galaxies and major mergers between them, to investigate the effect of feedback
from both an active galactic nucleus (AGN) and supernovae on the galaxy's
evolution. Several AGN methods from the literature are used independently and
in conjunction with supernova feedback to isolate the most important factors of
these feedback processes. We find that in isolated galaxies, supernovae
dominate the suppression of star formation but the star formation rate is
unaffected by the presence of an AGN. In mergers the converse is true when
models with strong AGN feedback are considered, shutting off star formation
before a starburst can occur. AGN and supernovae simulated together suppress
star formation only slightly more than if they acted independently. This
low-level interaction between the feedback processes is due to AGN feedback
maintaining the temperature of a hot halo of gas formed by supernovae. For each
of the feedback processes the heating temperature is the dominant parameter
rather than the overall energy budget or timing of heating events. Finally, we
find that the black hole mass is highly resolution dependent, with more massive
black holes found in lower resolution simulations.


title:
Zygmund-type inequalities for an operator preserving inequalities
  between polynomials

abstract:
  In this paper, we present certain new $L_p$ inequalities for $\mathcal
B_{n}$-operators which include some known polynomial inequalities as special
cases.


title: "Winter is coming"

abstract:
  Those that do not sow care little about such mundane things as equinoxes or
planting seasons, or even crop rotation for that matter. Wherever and whenever
the reavers reave, the mood is always foul and the nights are never warm or
pleasant. For the rest of the good folks of Westeros, however, a decent grasp
of the long-term weather forecast is a necessity. Many a maester have tried to
play the Game of Weather Patterns and foretell when to plant those last turnip
seeds, hoping for a few more years of balmy respite. Tried and failed. For
other than the somewhat vague (if not outright meaningless) omens of "Winter is
Coming", their meteorological efforts have been worse than useless. To right
that appalling wrong, here we attempt to explain the apparently erratic
seasonal changes in the world of G.R.R.M. A natural explanation for such
phenomena is the unique behavior of a circumbinary planet. Thus, by speculating
that the planet under scrutiny is orbiting a pair of stars, we utilize the
power of numerical three-body dynamics to predict that, unfortunately, it is
not possible to predict either the length, or the severity of any coming
winter. We conclude that, alas, the Maesters were right -- one can only throw
their hands in the air in frustration and, defeated by non-analytic solutions,
mumble "Coming winter? May be long and nasty (~850 days, T<268K) or may be
short and sweet (~600 days, T~273K). Who knows..."


title:
HerMES: The Contribution to the Cosmic Infrared Background from Galaxies
  Selected by Mass and Redshift

abstract:
  We quantify the fraction of the cosmic infrared background (CIB) that
originates from galaxies identified in the UV/optical/near-infrared by stacking
81,250 (~35.7 arcmin^2) K-selected sources (K_AB < 24.0), split according to
their rest-frame U - V vs. V - J colors into 72,216 star-forming and 9,034
quiescent galaxies, on maps from Spitzer/MIPS (24um), Herschel/SPIRE (250, 350,
500um), Herschel/PACS (100, 160um), and AzTEC (1100um). The fraction of the CIB
resolved by our catalog is (69 $\pm$ 15)% at 24um, (78 $\pm$ 17)% at 70um, (58
$\pm$ 13)% at 100um, (78 $\pm$ 18)% at 160um, (80 $\pm$ 17)% at 250um, (69
$\pm$ 14)% at 350um, (65 $\pm$ 12)% at 500um, and (45 $\pm$ 8)% at 1100um. Of
that total, about 95% originates from star-forming galaxies, while the
remaining 5% is from apparently quiescent galaxies. The CIB at $\lambda$ <
200um is sourced predominantly from galaxies at z < 1, while at $\lambda$ >
200um the bulk originates from 1 < z < 2. Galaxies with stellar masses log(M/
M_sun)=9.5-11 are responsible for the majority of the CIB, with those in the
log(M/ M_sun)=9.5-10 contributing mostly at $\lambda$ < 250um, and those in the
log(M/ M_sun)=10.5-11 bin dominating at $\lambda$ > 350um. The contribution
from galaxies in the log(M/ M_sun)=9.0-9.5 and log(M/ M_sun)=11.0-12.0 stellar
mass bins contribute the least, both of order 5%, although the highest
stellar-mass bin is a significant contributor to the luminosity density at z >
2. The luminosities of the galaxies responsible for the CIB shifts from a
combination of "normal" and luminous infrared galaxies (LIRGs) at $\lambda$ <
160um, to LIRGs at 160um < $\lambda$ < 500um, to finally LIRGs and
ultra-luminous infrared galaxies (ULIRGs) at $\lambda$ > 500um. Stacking
analyses were performed with SIMSTACK (available at
http://www.astro.caltech.edu/~viero/viero_homepage/toolbox.html) which accounts
for possible biases due to clustering.


title:
Discovery of a Large Population of Ultraluminous X-ray Sources in the
  Bulge-less Galaxies NGC 337 and ESO 501-23

abstract:
  We have used Chandra observations of eight bulge-less disk galaxies to
identify new ultraluminous X-ray source (ULX) candidates, study their high mass
X-ray binary (HMXB) population, and search for low-luminosity active galactic
nuclei (AGN). We report the discovery of 16 new ULX candidates in our sample of
galaxies. Eight of these are found in the star forming galaxy NGC 337, none of
which are expected to be background contaminants. The HMXB luminosity function
of NGC 337 implies a star formation rate (SFR) of 6.8$^{+4.4}_{-3.5}$ \msun\
yr$^{-1}$, consistent at 1.5$\sigma$ with a recent state of the art SFR
determination. We also report the discovery of a bright ULX candidate (X-1) in
ESO 501-23. X-1's spectrum is well fit by an absorbed power law with $\Gamma =
1.18^{+0.19}_{-0.11}$ and N$\rm{_H}$ = 1.13$^{+7.07}_{-1.13} \times 10^{20}$
cm$^{-2}$, implying a 0.3-8 keV flux of $1.08^{+0.05}_{-0.07} \times 10^{-12}$
\esc. Its X-ray luminosity (L$_X$) is poorly constrained due to uncertainties
in the host galaxy's distance, but we argue that its spectrum implies L$_X >
10^{40}$ \es. An optical counterpart to this object may be present in HST
imaging. We also identify ULX candidates in IC 1291, PGC 3853, NGC 5964 and NGC
2805. We find no evidence of nuclear activity in the galaxies in our sample,
placing a flux upper limit of $4 \times 10^{-15}$ \esc\ on putative AGN.
Additionally, the type II-P supernova SN 2011DQ in NGC 337, which exploded 2
months before our X-ray observation, is undetected.


title: Low Energy Description of Quantum Gravity and Complementarity

abstract:
  We consider a framework in which low energy dynamics of quantum gravity is
described preserving locality, and yet taking into account the effects that are
not captured by the naive global spacetime picture, e.g. those associated with
black hole complementarity. Our framework employs a "special relativistic"
description of gravity; specifically, gravity is treated as a force measured by
the observer tied to the coordinate system associated with a freely falling
local Lorentz frame. We identify, in simple cases, regions of spacetime in
which low energy local descriptions are applicable as viewed from the freely
falling frame; in particular, we identify a surface called the gravitational
observer horizon on which the local proper acceleration measured in the
observer's coordinates becomes the cutoff (string) scale. This allows for
separating between the "low-energy" local physics and "trans-Planckian"
intrinsically quantum gravitational (stringy) physics, and allows for
developing physical pictures of the origins of various effects. We explore the
structure of the Hilbert space in which the proposed scheme is realized in a
simple manner, and classify its elements according to certain horizons they
possess. We also discuss implications of our framework on the firewall problem.
We conjecture that the complementarity picture may persist due to properties of
trans-Planckian physics.


title: Cosmological Perturbations in Extended Massive Gravity

abstract:
  We study cosmological perturbations around self-accelerating solutions to two
extensions of nonlinear massive gravity: the quasi-dilaton theory and the
mass-varying theory. We examine stability of the cosmological solutions, and
the extent to which the vanishing of the kinetic terms for scalar and vector
perturbations of self-accelerating solutions in massive gravity is generic when
the theory is extended. We find that these kinetic terms are in general
non-vanishing in both extensions, though there are constraints on the
parameters and background evolution from demanding that they have the correct
sign. In particular, the self-accelerating solutions of the quasi-dilaton
theory are always unstable to scalar perturbations with wavelength shorter than
the Hubble length.


title:
Implications of the spectroscopic abundances in {\alpha} Centauri A and
  B

abstract:
  Regardless of their close proximity, abundance measurements for both stars in
{\alpha} Centauri by different groups have led to varying results. We have
chosen to combine the abundance ratios from five similar data sets in order to
reduce systematic effects that may have caused inconsistencies. With these
collated relative abundance measurements, we find that the {\alpha} Cen system
and the Sun were likely formed from the same material, despite the [Fe/H]
enrichment observed in the {\alpha} Cen binaries: 0.28 and 0.31 dex,
respectively. Both {\alpha} Centauri A and B exhibit relative abundance ratios
that are generally solar, with the mean at 0.002 and 0.03 dex, respectively.
The refractory elements (condensation temperature > 900 K) in each have a mean
of -0.02 and 0.01 dex and a 1{\sigma} uncertainty of 0.09 and 0.11 dex,
respectively. Given the trends seen when analyzing the refractory abundances
[X/Fe] with condensation temperature, we find it possible that {\alpha}
Centauri A may host a yet undiscovered planet.


title: Calcium H & K Induced by Galaxy Halos

abstract:
  We present a measurement of the mean density profile of Ca II gas around
galaxies out to ~ 200 kpc, traced by Fraunhofer's H & K absorption lines. The
measurement is based on cross-correlating the positions of about one million
foreground galaxies at z ~ 0.1 and the flux decrements induced in the spectra
of about 10^5 background quasars from the Sloan Digital Sky Survey. This
technique allows us to trace the total amount of Ca II absorption induced by
the circumgalactic medium, including absorbers too weak to be detected in
individual spectra. We can statistically measure Ca II rest equivalent widths
down to several mA, corresponding to column densities of about 5x10^10 cm^{-2}.
We find that the Ca II column density distribution follows N ~ rp^{-1.4} and
the mean Ca II mass in the halo within 200 kpc is ~ 5x10^3 Msolar, averaged
over the foreground galaxy sample with median mass ~ 10^10.3 Msolar. This is
about an order-of-magnitude larger than the Ca II mass in the interstellar
medium of the Milky Way, suggesting more than 90% of Ca II in the Universe is
in the circum- and inter-galactic environments. Our measurements indicate that
the amount of Ca II in halos is larger for galaxies with higher stellar mass
and higher star formation rate. For edge-on galaxies we find Ca II to be more
concentrated along the minor axis, i.e. in the polar direction. This suggests
that bipolar outflows induced by star formation must have played a significant
role in producing Ca II in galaxy halos.


title:
A Chandra Snapshot Survey for 3C Radio Galaxies with redshifts between
  0.3 and 0.5

abstract:
  This paper contains an analysis of short Chandra observations of 19 3C
sources with redshifts between 0.3 and 0.5 not previously observed in the
X-rays. This sample is part of a project to obtain Chandra data for all of the
extragalactic sources in the 3C catalogue. Nuclear X-ray intensities as well as
any X-ray emission associated with radio jet knots, hotspots or lobes have been
measured in 3 energy bands: soft, medium and hard. Standard X-ray spectral
analysis for the 4 brightest nuclei has been also performed. X-ray emission was
detected for all the nuclei of the radio sources in the current sample with the
exception of 3C 435A. There is one compact steep spectrum (CSS) source while
all the others are FRII radio galaxies. X-ray emission from two galaxy clusters
(3C 19 and 3C 320); from 6 hotspots in 4 radio galaxies (3C 16, 3C 19, 3C
268.2, 3C 313); and extended X-ray emission on kpc scales in 3C 187 and 3C 313,
has been detected.


title:
Millimeter dust emission compared with other mass estimates in N11
  molecular clouds in the LMC

abstract:
  CO and dust emission at millimeter wavelengths are independent tracers of
cold interstellar matter, which have seldom been compared on the scale of GMCs
in other galaxies. In this study, and for the first time in the Large
Magellanic Cloud, we compute the molecular cloud masses from the mm emission of
the dust and compare them with the masses derived from their CO luminosity and
virial theorem. We present CO (J=1-0,2-1) and 1.2 mm continuum observations of
the N11 star forming region in the LMC obtained with the SEST telescope and the
SIMBA bolometer, respectively. We use the CO data to identify individual
molecular clouds and measure their physical properties. The correlations
between the properties of the N11 clouds are in agreement with those found in
earlier studies in the LMC that sample a larger set of clouds and a larger
range of cloud masses. For the N11 molecular clouds, we compare the masses
estimated from the CO luminosity (Xco\Lco), the virial theorem (Mvir) and the
millimeter dust luminosity (L_d). The measured ratios Lco/Mvir and L_d/Mvir
constrain the Xco and K_d (dust emissivity at 1.2 mm per unit gas mass)
parameters as a function of the virial parameter a_vir. The comparison between
the different mass estimates yields a Xco-factor of 8.8x10^20 cm-2/(K km s-1) x
a_vir and a K_d parameter of 1.5x10^-3 cm2/g x a_vir. We compare our N11
results with a similar analysis for molecular clouds in the Gould's Belt. We do
not find in N11 a large discrepancy between the dust mm and virial masses as
reported in earlier studies of molecular clouds in the SMC. The ratio between
L_d and Mvir in N11 is half of that measured for Gould's Belt clouds, which can
be accounted for by a factor of two lower gas-to-dust mass ratio, as the
difference in gas metallicities. If the two samples have similar a_vir values,
this result implies that their dust far-IR properties are also similar.


title: On the Coagulation and Size Distribution of Pressure Confined Cores

abstract:
  Observations of the Pipe Nebula have led to the discovery of dense starless
cores. The mass of most cores is too small for their self gravity to hold them
together. Instead, they are thought to be pressure confined. The observed dense
cores' mass function (CMF) matches well with the initial mass function (IMF) of
stars in young clusters. Similar CMF's are observed in other star forming
regions such as the Aquila Nebula, albeit with some dispersion. The shape of
these CMF provides important clues to the competing physical processes which
lead to star formation and its feedback on the interstellar media. In this
paper, we investigate the dynamical origin of the the mass function of starless
cores which are confined by a warm, less dense medium. We consider the
coagulation between the cold cores and their ablation due to Kelvin-Helmholtz
instability induced by their relative motion through the warm medium. We are
able to reproduce the observed CMF among the starless cores in the Pipe nebula.
Our results indicate that in environment similar to the Pipe nebula: 1) before
the onset of their gravitational collapse, the mass distribution of the
progenitor cores is similar to that of the young stars, 2) the observed CMF is
a robust consequence of dynamical equilibrium between the coagulation and
ablation of cores, and 3) a break in the slope of the CMF is due to the
enhancement of collisional cross section and suppression of ablation for cores
with masses larger than the cores' Bonnor-Ebert mass.


title:
A highly elongated prominent lens at z=0.87: first strong lensing
  analysis of El Gordo

abstract:
  We present the first strong-lensing (SL) analysis of the galaxy cluster
ACT-CL J0102-4915 (\emph{El Gordo}), in recent \emph{HST}/ACS images, revealing
a prominent strong lens at a redshift of $z=0.87$. This finding adds to the
already-established unique properties of \emph{El Gordo}: it is the most
massive, hot, X-ray luminous, and bright Sunyaev-Zeldovich effect cluster at
$z\gtrsim0.6$, and the only `bullet'-like merging cluster known at these
redshifts. The lens consists of two merging massive clumps, where for a source
redshift of $z_{s}\sim2$ each clump exhibits only a small, separate critical
area, with a total area of $0.69\pm0.11\sq\arcmin$ over the two clumps. For a
higher source redshift, $z_{s}\sim4$, the critical curves of the two clumps
merge together into one bigger and very elongated lens (axis ratio
$\simeq5.5$), enclosing an effective area of $1.44\pm0.22\sq\arcmin$. The
critical curves continue expanding with increasing redshift so that for
high-redshift sources ($z_{s}\gtrsim9$) they enclose an area of
$\sim1.91\pm0.30\sq\arcmin$ (effective $\theta_{e}\simeq46.8\pm3.7\arcsec$) and
a mass of $6.09\pm1.04\times10^{14}M_{\odot}$. According to our model, the area
of high magnification ($\mu>10$) for such high redshift sources is
$\simeq1.2\sq\arcmin$, and the area with $\mu>5$ is $\simeq2.3\sq\arcmin$,
making \emph{El Gordo} a compelling target for studying the high-redshift
Universe. We obtain a strong lower limit on the total mass of \emph{El Gordo},
$\gtrsim1.7\times10^{15}M_{\odot}$ from the SL regime alone, suggesting a total
mass of, roughly, $M_{200}\sim2.3\times10^{15}M_{\odot}$. Our results should be
revisited when additional spectroscopic and \emph{HST} imaging data are
available.


title: Effects of superstructure environment on galaxy groups

abstract:
  We analyse properties of galaxy groups and their dependence on the large
scale environment as defined by superstructures. We find that group galaxy
cross correlations depend only on group properties regardless the groups reside
in superstructures. This indicates that the total galaxy density profile around
groups is independent of the global environment. At a given global luminosity,
a proxy to group total mass, groups have a larger stellar mass content by a
factor 1.3, a relative excess independent of the group luminosity. Groups in
superstructures have 40 per cent higher velocity dispersions and systematically
larger minimal enclosing radii. We also find that the stellar population of
galaxies in groups in superstructures is systematically older as infered from
the galaxy spectra Dn4000 parameter. Although the galaxy number density profile
of groups is independent of environment, the star formation rate and stellar
mass profile of the groups residing in superstructures differs from groups
elsewhere. For groups residing in superstructures, the combination of a larger
stellar mass content and star formation rate produces a larger time scale for
star formation regardless the distance to the group center. Our results provide
evidence that groups in superstructures formed earlier than elsewhere, as
expected in the assembly bias scenario.


title: An efficient spectral interpolation routine for the TwoPunctures code

abstract:
  TwoPunctures is perhaps the most widely-adopted code for generating binary
black hole "puncture" initial data and interpolating these (spectral) data onto
evolution grids. In typical usage, the bulk of this code's run time is spent in
its spectral interpolation routine. We announce a new publicly-available
spectral interpolation routine that improves the performance of the original
interpolation routine by a factor of ~100, yielding results consistent with the
original spectral interpolation routine to roundoff precision. This note serves
as a guide for installing this routine both in the original standalone
TwoPunctures code and the Einstein Toolkit supported version of this code.


title: S-duality Improved Superstring Perturbation Theory

abstract:
  Strong - weak coupling duality in string theory allows us to compute physical
quantities both at the weak coupling end and at the strong coupling end.
Furthermore perturbative string theory can be used to compute corrections to
the leading order formula at both ends. We explore the possibility of
constructing a smooth interpolating formula that agrees with the perturbation
expansion at both ends and leads to a fairly accurate determination of the
quantity in consideration over the entire range of the coupling constant. We
apply this to study the mass of the stable non-BPS state in SO(32) heterotic /
type I string theory with encouraging results. In particular our result
suggests that after taking into account one loop corrections to the mass in the
heterotic and type I string theory, the interpolating function determines the
mass within 10% accuracy over the entire range of coupling constant.


title:
Tidal dissipation and eccentricity pumping: Implications for the depth
  of the secondary eclipse of 55 Cnc e

abstract:
  We use the super Earth 55 Cnc e as a case study to address an observable
effect of tidal heating. We investigate whether planet-planet interactions can
force the eccentricity of this planet to a level affecting the eclipse depth
observed with Spitzer. Using the constant time lag tidal model, we first
calculate the observed planet flux as a function of albedo and eccentricity,
for different tidal dissipation constants and for two extreme cases: a planet
with no heat redistribution and a planet with full heat redistribution. We
derive the values of albedo and eccentricity that match the observed transit
depth. We then perform N-body simulations of the planetary system including
tides and General Relativity to follow the evolution of the eccentricity of
planet e. We compare the range of eccentricities given by the simulations with
the eccentricities required to alter the eclipse depth. We find that the
eccentricity of planet e can be large enough to contribute at a measurable
level to the thermal emission measured with Spitzer. This affects the
constraints on the albedo of the planet, which can be as high as 0.9 (instead
of 0.55 when ignoring tidal heating). We also derive a maximum value for the
eccentricity of planet e directly from the eclipse depth: e<0.015 assuming
Earth's dissipation constant. Transiting exoplanets in multiple planet systems
are exceptional targets for testing tidal models because their tidal luminosity
may be observable. Future multi-wavelengths observations of eclipse depth and
phase curves (for instance with EChO and JWST) should allow us to better
resolve the temperature map of these planets and break the degeneracy between
albedo and tidal heating that remains for single band observations. In
addition, an accurate determination of the eccentricity will make it possible
to constrain the dissipation rate of the planet and to probe its internal
structure.


title: A Plateau in the Planet Population Below Twice the Size of Earth

abstract:
  We carry out an independent search of Kepler photometry for small transiting
planets with sizes 0.5--8.0 times that of Earth and orbital periods between 5
and 50 days, with the goal of measuring the fraction of stars harboring such
planets. We use a new transit search algorithm, TERRA, optimized to detect
small planets. We restrict our stellar sample to include the 12,000 stars
having the lowest photometric noise in the Kepler survey. We report 129 planet
candidates having radii less than 6 Earth-radii found in 3 years of Kepler
photometry. Forty-seven of these candidates are not in Batalha et al. (2012).
We gather Keck HIRES spectra for the majority of these targets leading to
precise stellar radii and hence precise planet radii. We inject synthetic
dimmings from mock transiting planets into the actual Kepler photometry and
analyze that photometry with TERRA to assess detection completeness. We compute
the occurrence of planets as a function of planet radius and period, correcting
for the detection completeness. The resulting distribution of planet sizes
exhibits a power law rise in occurrence from 5.7 Earth-radii down to 2
Earth-radii, as found in Howard et al. (2012). That rise clearly ends at 2
Earth-radii. The occurrence of planets is consistent with constant from 2
Earth-radii toward 1 Earth-radius. This unexpected plateau in planet occurrence
at 2 Earth-radii suggests distinct planet formation processes for planets above
and below 2 Earth-radii. We find 15.1% of solar type stars---roughly one in
six---has a 1--2 Earth-radii planet with P = 5--50 days.


title:
A Smooth Landscape: Ending Saddle Point Inflation Requires Features to
  be Shallow

abstract:
  We consider inflation driven near a saddle point in a higher dimensional
field space, which is the most likely type of slow roll inflation on the string
theoretical landscape; anthropic arguments need to be invoked in order to find
a sufficiently flat region. To give all inflatons large masses after inflation
and yield a small but positive cosmological constant, the trajectory in field
space needs to terminate in a hole on the inflationary plateau, introducing a
curved end-of-inflation hypersurface. We compute non-Gaussianities (bi- and
tri-spectrum) caused by this curved hyper-surface and find a negative,
potentially large, local non-linearity parameter. To be consistent with current
observational bounds, the hole needs to be shallow, i.e. considerably wider
than deep in natural units. To avoid singling out our vacuum as special (i.e.
more special than a positive cosmological constant entails), we deduce that all
features on field space should be similarly shallow, severely limiting the type
of landscapes one may use for inflationary model building.
  We justify the use of a truncated Fourier series with random coefficients,
which are suppressed the higher the frequency, to model such a smooth landscape
by a random potential, as is often done in the literature without a good a
priory reason.


title:
Gravitational wave parameter estimation with compressed likelihood
  evaluations

abstract:
  One of the main bottlenecks in gravitational wave (GW) astronomy is the high
cost of performing parameter estimation and GW searches on the fly. We propose
a novel technique based on Reduced Order Quadratures (ROQs), an application and
data-specific quadrature rule, to perform fast and accurate likelihood
evaluations. These are the dominant cost in Markov chain Monte Carlo (MCMC)
algorithms, which are widely employed in parameter estimation studies, and so
ROQs offer a new way to accelerate GW parameter estimation. We illustrate our
approach using a four dimensional GW burst model embedded in noise. We build an
ROQ for this model, and perform four dimensional MCMC searches with both the
standard and ROQs quadrature rules, showing that, for this model, the ROQ
approach is around 25 times faster than the standard approach with essentially
no loss of accuracy. The speed-up from using ROQs is expected to increase for
more complex GW signal models and therefore has significant potential to
accelerate parameter estimation of GW sources such as compact binary
coalescences.


title: A type D structure in Khovanov homology

abstract:
  We describe the first part of a gluing theory for the bigraded Khovanov
homology with integer coefficients. This part associates a type D structure to
a tangle properly embedded in a half-space and proves that the homotopy class
of the type D structure is an invariant of the isotopy class of the tangle. The
construction is modeled off bordered Heegaard-Floer homology, but uses only
combinatorial/diagrammatic methods


title:
Origin and Transport Signatures of Spin-Orbit Interactions in One- and
  Two-Dimensional SrTiO$_3$-Based Heterostructures

abstract:
  We study origin of Rashba spin-orbit interaction at SrTiO$_3$ surfaces and
LaAlO$_3$/SrTiO$_3$ interfaces by considering the interplay between atomic
spin-orbit coupling and inversion asymmetry at the surface or interface. We
show that, in a simple tight-binding model involving 3d $t_{2g}$ bands of Ti
ions, the induced spin-orbit coupling in the $d_{xz}$ and $d_{yz}$ bands is
cubic in momentum whereas the spin-orbit interaction in the $d_{xy}$ band has
linear momentum dependence. We also find that the spin-orbit interaction in
one-dimensional channels at LaAlO$_3$/SrTiO$_3$ interfaces is linear in
momentum for all bands. We discuss implications of our results for transport
experiments on SrTiO$_3$ surfaces and LaAlO$_3$/SrTiO$_3$ interfaces. In
particular, we analyze the effect of a given spin-orbit interaction term on
magnetotransport of LaAlO$_3$/SrTiO$_3$ by calculating weak anti-localization
corrections to the conductance and to universal conductance fluctuations.


title: A type A structure in Khovanov Homology

abstract:
  Inspired by bordered Floer homology, we describe a type A structure on a
Khovanov homology for a tangle, which complements the type D structure in a
previous paper. The type A structure is a differential module over a certain
algebra. This can be paired with the type D structure to recover the Khovanov
chain complex. The homotopy type of the type A structure is a tangle invariant,
and homotopy equivalences of the type A structure result in chain homotopy
equivalences on the Khovanov chain complex. We can use this to simplify
computations and introduce a modular approach to the computation of Khovanov
homologies. This approach adds to the literature even in the case of a connect
sum, where the techniques here will allow an exact computation of Khovanov
homology from the structures for two tangles coming from the summands. Several
examples are included, showing in particular how we can compute the correct
torsion summands for the Khovanov homology of the connect sum. A lengthy
appendix is devoted to establishing the theory of these structures over a
characterstic zero ring.


title: Complexity Aided Design: the FuturICT Technological Innovation Paradigm

abstract:
  "In the next century, planet earth will don an electronic skin. It will use
the Internet as a scaffold to support and transmit its sensations. This skin is
already being stitched together. It consists of millions of embedded electronic
measuring devices: thermostats, pressure gauges, pollution detectors, cameras,
microphones, glucose sensors, EKGs, electroencephalographs. These will probe
and monitor cities and endangered species, the atmosphere, our ships, highways
and fleets of trucks, our conversations, our bodies--even our dreams ....What
will the earth's new skin permit us to feel? How will we use its surges of
sensation? For several years--maybe for a decade--there will be no central
nervous system to manage this vast signaling network. Certainly there will be
no central intelligence...some qualities of self-awareness will emerge once the
Net is sensually enhanced. Sensuality is only one force pushing the Net toward
intelligence". These statements are quoted by an interview by Cherry Murray,
Dean of the Harvard School of Engineering and Applied Sciences and Professor of
Physics. It is interesting to outline the timeliness and highly predicting
power of these statements. In particular, we would like to point to the
relevance of the question "What will the earth's new skin permit us to feel?"
to the work we are going to discuss in this paper. There are many additional
compelling questions, as for example: "How can the electronic earth's skin be
made more resilient?"; "How can the earth's electronic skin be improved to
better satisfy the need of our society?";"What can the science of complex
systems contribute to this endeavour?"


title:
Greybody factors for non-minimally coupled scalar fields in
  Schwarzschild-de Sitter spacetime

abstract:
  We compute the greybody factors for non-minimally coupled scalar fields in
four-dimensional Schwarzschild-de Sitter spacetime. In particular, we
demonstrate that the zero-angular-momentum greybody factor generically tends to
zero in the zero-frequency limit like frequency squared if there is
non-vanishing coupling to the scalar curvature. This is in contrast with the
minimally coupled case, where the greybody factor is known to tend to a finite
constant. We also study the Hawking radiation for non-minimally coupled
massless scalar fields in Schwarzschild-de Sitter spacetime, formulate a
sensible notion of a generalized absorption cross section and investigate its
properties.


title: Baryogenesis with Higher Dimension Operators

abstract:
  We propose a simple model of baryogenesis comprised of the standard model
coupled to a singlet X via higher dimension operators O. In the early universe,
X is thermalized by O mediated scattering processes before it decouples
relativistically and evolves into a sizable fraction of the total energy
density. Eventually, X decays via O in an out of equilibrium, baryon number and
CP violating process that releases entropy and achieves baryogenesis for a
broad range of parameters. The decay can also produce a primordial abundance of
dark matter. Because X may be as light as a TeV, viable regions of parameter
space lie within reach of experimental probes of neutron-antineutron
oscillation, flavor physics, and proton decay.


title: Transversity Parton Distribution

abstract:
  Transversity distribution is one of the three fundamental parton
distributions that completely describe polarized spin 1/2 nucleon. Its chiral
odd nature prevented for many years its experimental exploration, however
presently we have obtained great deal of information about this distribution.
This includes experimental data from Semi Inclusive Deep Inelastic Scattering,
knowledge of scale dependence and phenomenological extractions. I will discuss
main features of this distribution and indicate the future improvements of our
knowledge.


title: The Emerging Energy Web

abstract:
  There is a general need of elaborating energy-effective solutions for
managing our increasingly dense interconnected world. The problem should be
tackled in multiple dimensions -technology, society, economics, law,
regulations, and politics- at different temporal and spatial scales. Holistic
approaches will enable technological solutions to be supported by
socio-economic motivations, adequate incentive regulation to foster investment
in green infrastructures coherently integrated with adequate energy
provisioning schemes. In this article, an attempt is made to describe such
multidisciplinary challenges with a coherent set of solutions to be identified
to significantly impact the way our interconnected energy world is designed and
operated.


title:
Newtonian Semiclassical Gravity in the Ghirardi-Rimini-Weber Theory with
  Matter Density Ontology

abstract:
  We propose a Newtonian semiclassical gravity theory based on the GRW collapse
theory with matter density ontology (GRWm), which we term GRWmN. The theory is
proposed because, as we show, the standard Newtonian semiclassical gravity
theory based on the Schroedinger-Newton equations does not have a consistent
Born rule probability interpretation for gravitationally self-interacting
particles and implies gravitational cat states for macroscopic mass
superpositions. By contrast, we show that GRWmN has a consistent statistical
description of gravitationally self-interacting particles and adequately
suppresses the cat states for macroscopic superpositions. Two possible routes
to experimentally testing GRWmN are also considered. We conclude with a
discussion of possible variants of GRWmN, what a general relativistic extension
would involve, and various objections that might be raised against
semiclassical gravity theories like GRWmN.


title: Partitioning bases of topological spaces

abstract:
  We investigate whether an arbitrary base for a dense-in-itself topological
space can be partitioned into two bases. We prove that every base for a T_3
Lindel\"of topology can be partitioned into two bases while there exists a
consistent example of a first countable, 0-dimensional, Hausdorff space of size
continuum and weight \omega_1 which admits a point countable base without a
partition to two bases. Several related results are proved and the paper
finishes with a list of open problems.


title: Coauthorship and citation in scientific publishing

abstract:
  A large number of published studies have examined the properties of either
networks of citation among scientific papers or networks of coauthorship among
scientists. Here, using an extensive data set covering more than a century of
physics papers published in the Physical Review, we study a hybrid
coauthorship/citation network that combines the two, which we analyze to gain
insight into the correlations and interactions between authorship and citation.
Among other things, we investigate the extent to which individuals tend to cite
themselves or their collaborators more than others, the extent to which they
cite themselves or their collaborators more quickly after publication, and the
extent to which they tend to return the favor of a citation from another
scientist.


title:
Spin and Dipole Ordering in Ni_2InSbO_6 and Ni_2ScSbO_6 with
  corundum-related structure

abstract:
  The complex metal oxides Ni2InSbO6 (NISO) and Ni2ScSbO6 (NSSO) have been
prepared in form of polycrystalline powders by a solid state reaction route.
The crystal structure and magnetic properties of the compounds were
investigated using a combination of X-ray and neutron powder diffraction,
electron microscopy, calorimetric and magnetic measurements. The compounds
adopt a trigonal structure, space group R3, of the corundum related Ni3TeO6
(NTO) type. Only one of the octahedral Ni positions (Ni(2)) of the NTO
structure was found to be occupied by In (Sc). NTO has non-centrosymmetric
structure and is ferroelectric below 1000 K, dielectric and second harmonic
measurements suggest that also NISO and NSSO are correspondingly ferroelectric.
Magnetization measurements signified antiferromagnetic ordering below TN=60 K
(NSSO) and 76 K (NISO). The magnetic structure is formed by two
antiferromagnetically coupled incommensurate helices with the spiral axis along
the b-axis and propagation vector k = [0, ky,0] with ky= 0.036(1) (NSSO) and
ky= 0.029(1) (NISO). The observed structural and magnetic properties of NISO
and NSSO are discussed and compared with those of NTO.


title: On the metric of the space of states in a modified QCD

abstract:
  The form of the resulting Feynman propagators in a proposed local and gauge
invariant QCD for massive fermions suggests the existence of indefinite metric
associated to quark states, a property that might relate it with the known
Lee-Wick theories. Thus, the nature of the asymptotic free quark states in the
theory is investigated here by quantizing the quadratic part of the quark
action. As opposite to the case in the standard QCD, the free theory does not
show Hamiltonian constraints. The propagation modes include a family of
massless waves and a complementary set of massive oscillations. The theory can
be quantized in a way that the massive modes show positive metric and the
massless ones exhibit negative norms. It is remarked that, since QCD is
expected to not exhibit gluon or quark asymptotic states, the presence of
negative metric massless modes does not constitute a definite drawback of the
theory. In addition, the fact that the positive metric quark states are
massive, seems to be a good feature of the model, being consistent with the
approximate existence of asymptotically free massive states in high energy
processes.


title: The turbulence boundary of a temporal jet

abstract:
  We examine the structure of the turbulence boundary of a temporal plane jet
at $Re=5000$ using statistics conditioned on the enstrophy. The data is
obtained by direct numerical simulation and threshold values span 24 orders of
magnitude, ranging from essentially irrotational fluid outside the jet to fully
turbulent fluid in the jet core. We use two independent estimators for the
local entrainment velocity $v_n$ based on the enstrophy budget. The data show
clear evidence for the existence of a viscous superlayer (VSL) that envelopes
the turbulence. The VSL is a nearly one-dimensional layer with low surface
curvature. We find that both its area and viscous transport velocity adjust to
the imposed rate so that the integral entrainment flux is independent of
threshold, although low-Reynolds-number effects play a role for the case under
consideration. This threshold independence is consistent with the inviscid
nature of the integral rate of entrainment. A theoretical model of the VSL is
developed that is in reasonably good agreement with the data and predicts that
the contribution of viscous transport and dissipation to interface propagation
have magnitude $2 v_n$ and $-v_n$, respectively. We further identify a
turbulent core region (TC) which is a region that shrinks over time and a
buffer region connecting the VSL and the TC that grows in time and where the
inviscid enstrophy production is important. The BR shows many similarities with
the turbulent-nonturbulent interface (TNTI), although the TNTI seems to extend
into the TC. The average distance between the TC and the VSL, i.e.\ the BR
thickness is about 10 Kolmogorov length scales or half a Taylor length scale,
indicating that intense turbulent flow regions and viscosity-dominated regions
are in close proximity.


title:
Signatures of multiple stellar populations in unresolved extragalactic
  globular/ young massive star clusters

abstract:
  We present an investigation of potential signatures of the formation of
multiple stellar populations in recently formed extragalactic star clusters.
All of the Galactic globular clusters for which good samples of individual
stellar abundances are available show evidence for multiple populations. This
appears to require that multiple episodes of star formation and light element
enrichment are the norm in the history of a globular cluster. We show that
there are detectable observational signatures of multiple formation events in
the unresolved spectra of massive, young extragalactic star clusters. We
present the results of a pilot program to search for one of the cleanest
signatures that we identify - the combined presence of emission lines from a
very recently formed population and absorption lines from a somewhat older
population. A possible example of such a system is identified in the Antennae
galaxies. This source's spectrum shows evidence of two stellar populations with
ages of 8 Myr and 80 Myr. Further investigation shows that these populations
are in fact physically separated, but only by a projected distance of 59 pc. We
show that the clusters are consistent with being bound and discuss the
possibility that their coalescence could result in a single globular cluster
hosting multiple stellar populations. While not the prototypical system
proposed by most theories of the formation of multiple populations in clusters,
the detection of this system in a small sample is both encouraging and
interesting. Our investigation suggests that expanded surveys of massive young
star clusters should detect more clusters with such signatures.


title: Explicit Computation of Certain Arakelov-Green Functions

abstract:
  Arakelov-Green functions defined on metrized graphs have important role in
relating arithmetical problems on algebraic curves into graph theoretical
problems. In this paper, we clarify the combinatorial interpretation of certain
Arakelov-Green functions by using electric circuit theory. The formulas we gave
clearly show that such functions are piece-wisely defined, and each piece is a
linear or quadratic function on each pair of edges of metrized graphs. These
formulas lead to an algorithm for explicit computation of Arakelov-Green
functions.


title:
Mice Infected with Low-virulence Strains of Toxoplasma gondii Lose their
  Innate Aversion to Cat Urine, Even after Extensive Parasite Clearance

abstract:
  Toxoplasma gondii chronic infection in rodent secondary hosts has been
reported to lead to a loss of innate, hard-wired fear toward cats, its primary
host. However the generality of this response across T. gondii strains and the
underlying mechanism for this pathogen mediated behavioral change remain
unknown. To begin exploring these questions, we evaluated the effects of
infection with two previously uninvestigated isolates from the three major
North American clonal lineages of T. gondii, Type III and an attenuated strain
of Type I. Using an hour-long open field activity assay optimized for this
purpose, we measured mouse aversion toward predator and non-predator urines. We
show that loss of innate aversion of cat urine is a general trait caused by
infection with any of the three major clonal lineages of parasite.
Surprisingly, we found that infection with the attenuated Type I parasite
results in sustained loss of aversion at times post infection when neither
parasite nor ongoing brain inflammation were detectable. This suggests that T.
gondii-mediated interruption of mouse innate aversion toward cat urine may
occur during early acute infection in a permanent manner, not requiring
persistence of parasitecysts or continuing brain inflammation.


title:
A problem dependent analysis of SOCP algorithms in noisy compressed
  sensing

abstract:
  Under-determined systems of linear equations with sparse solutions have been
the subject of an extensive research in last several years above all due to
results of \cite{CRT,CanRomTao06,DonohoPol}. In this paper we will consider
\emph{noisy} under-determined linear systems. In a breakthrough
\cite{CanRomTao06} it was established that in \emph{noisy} systems for any
linear level of under-determinedness there is a linear sparsity that can be
\emph{approximately} recovered through an SOCP (second order cone programming)
optimization algorithm so that the approximate solution vector is (in an
$\ell_2$-norm sense) guaranteed to be no further from the sparse unknown vector
than a constant times the noise. In our recent work \cite{StojnicGenSocp10} we
established an alternative framework that can be used for statistical
performance analysis of the SOCP algorithms. To demonstrate how the framework
works we then showed in \cite{StojnicGenSocp10} how one can use it to precisely
characterize the \emph{generic} (worst-case) performance of the SOCP. In this
paper we present a different set of results that can be obtained through the
framework of \cite{StojnicGenSocp10}. The results will relate to \emph{problem
dependent} performance analysis of SOCP's. We will consider specific types of
unknown sparse vectors and characterize the SOCP performance when used for
recovery of such vectors. We will also show that our theoretical predictions
are in a solid agreement with the results one can get through numerical
simulations.