title: Interchange Reconnection Alfven Wave Generation

abstract:
  Given recent observational results of interchange reconnection processes in
the solar corona and the theoretical development of the S-Web model for the
slow solar wind, we extend the analysis of the 3D MHD simulation of interchange
reconnection by Edmondson et al. (Astrophys. J. 707, 1427, 2009). Specifically,
we analyze the consequences of the dynamic streamer-belt jump that corresponds
to flux opening by interchange reconnection. Information about the magnetic
field restructuring by interchange reconnection is carried throughout the
system by Alfven waves propagating away from the reconnection region,
distributing the shear and twist imparted by the driving flows, including
shedding the injected stress-energy and accumulated magnetic helicity along
newly open fieldlines. We quantify the properties of the reconnection-generated
wave activity in the simulation. There is a localized high-frequency component
associated with the current sheet/reconnection site and an extended
low-frequency component associated with the large-scale torsional Alfven wave
generated from the interchange reconnection field restructuring. The
characteristic wavelengths of the torsional Alfven wave reflect the spatial
size of the energized bipolar flux region. Lastly, we discuss avenues of future
research by modeling these interchange reconnection-driven waves and
investigating their observational signatures.


title:
Observations and Modeling of the Companions of Short Period Binary
  Millisecond Pulsars: Evidence for High-Mass Neutron Stars

abstract:
  We present observations of fields containing eight recently discovered binary
millisecond pulsars using the telescopes at MDM Observatory. Optical
counterparts to four of these systems are detected, one of which, PSR
J2214+3000, is a novel detection. Additionally, we present the fully
phase-resolved B, V, and R light curves of the optical counterparts to two
objects, PSR J1810+1744 and PSR J2215+5135 for which we employ model fitting
using the ELC model of Orosz & Hauschildt (2000) to measure the unknown system
parameters. For PSR J1810+1744 we find that the system parameters cannot be fit
even assuming that 100% of the spin-down luminosity of the pulsar is
irradiating the secondary, and so radial velocity measurements of this object
will be required for the complete solution. However, PSR J2215+5135 exhibits
light curves that are extremely well constrained using the ELC model and we
find that the mass of the neutron star is constrained by these and the radio
observations to be greater than 1.75 solar masses at the 3-sigma level. We also
find a discrepancy between the model temperature and the measured colors of
this object which we interpret as possible evidence for an additional
high-temperature source such as a quiescent disk. Given this and the fact that
PSR J2214+5135 contains a relatively high mass companion (greater than 0.1
solar masses), we propose that similar to the binary pulsar systems PSR
J1023+0038 and IGR J18245-2452, the pulsar may transition between accretion-
and rotation-powered modes.


title:
Synthetic streams in a Gravitational Wave inspiral search with a
  multi-detector network

abstract:
  Gravitational Wave Inspiral search with a global network of interferometers
when carried in a phase coherent fashion would mimic an effective
multi-detector network with synthetic streams constructed by the linear
combination of the data from different detectors. For the first time, we
demonstrate that the two synthetic data streams pertaining to the two
polarizations of Gravitational Wave can be derived prior to the
maximum-likelihood analysis in a most natural way using the technique of
singular-value-decomposition applied to the network signal-to-noise ratio
vector. We construct the network matched filters in combined network plus
spectral space which capture both the synthetic streams. We further show that
the network LLR is then sum of the LLR of each synthetic stream. The four
extrinsic parameters are mapped to the two amplitudes and two phases. The
maximization over these is a straightforward approach closely linked to the
single detector approach. Towards the end, we connect all the previous works
related to the multi-detector Gravitational Wave inspiral search and express in
the same notation in order to bring under the same footing.


title: Estimating the First-Light Time of the Type Ia Supernova 2014J in M82

abstract:
  The Type Ia supernova (SN Ia) 2014J in M82 (d~3.5 Mpc) was serendipitously
discovered by S. Fossey's group on 2014 Jan. 21 UT and has been confirmed to be
the nearest known SN Ia since at least SN 1986G. Although SN 2014J was not
discovered until ~7 days after first light, both the Katzman Automatic Imaging
Telescope at Lick Observatory and K. Itagaki obtained several prediscovery
observations of SN 2014J. With these data, we are able to constrain the
object's time of first light to be Jan. 14.75 UT, only 0.82+/-0.21 d before our
first detection. Interestingly, we find that the light curve is well described
by a varying power law, much like SN 2013dy, which makes SN 2014J the second
example of a changing power law in early-time SN Ia light curves. A
low-resolution spectrum taken on Jan. 23.388 UT, ~8.70 after first light, shows
that SN 2014J is a heavily reddened but otherwise spectroscopically normal SN
Ia.


title:
Uniform bounds for Fourier transforms of surface measures in R^3 with
  nonsmooth density

abstract:
  We prove uniform estimates for the decay rate of the Fourier transform of
measures supported on real-analytic hypersurfaces in R^3. If the surface
contains the origin and is oriented such that its normal at the origin is in
the direction of the z-axis and if dS denotes the surface measure for this
surface, then the measures under consideration are of the form K(x,y)g(z) dS
where K(x,y)g(z) is supported near the origin and both K(x,y) and g(z) are
allowed to have singularities. The estimates here generalize the previously
known sharp uniform estimates for when K(x,y)g(z) is smooth. The methods used
in this paper involve an explicit two-dimensional resolution of singularities
theorem, iterated twice, coupled with Van der Corput-type lemmas.


title: How to Influence People with Partial Incentives

abstract:
  We study the power of fractional allocations of resources to maximize
influence in a network. This work extends in a natural way the well-studied
model by Kempe, Kleinberg, and Tardos (2003), where a designer selects a
(small) seed set of nodes in a social network to influence directly, this
influence cascades when other nodes reach certain thresholds of neighbor
influence, and the goal is to maximize the final number of influenced nodes.
Despite extensive study from both practical and theoretical viewpoints, this
model limits the designer to a binary choice for each node, with no way to
apply intermediate levels of influence. This model captures some settings
precisely, e.g. exposure to an idea or pathogen, but it fails to capture very
relevant concerns in others, for example, a manufacturer promoting a new
product by distributing five "20% off" coupons instead of giving away one free
product.
  While fractional versions of problems tend to be easier to solve than
integral versions, for influence maximization, we show that the two versions
have essentially the same computational complexity. On the other hand, the two
versions can have vastly different solutions: the added flexibility of
fractional allocation can lead to significantly improved influence. Our main
theoretical contribution is to show how to adapt the major positive results
from the integral case to the fractional case. Specifically, Mossel and Roch
(2006) used the submodularity of influence to obtain their integral results; we
introduce a new notion of continuous submodularity, and use this to obtain
matching fractional results. We conclude that we can achieve the same greedy
$(1-1/e-\epsilon)$-approximation for the fractional case as the integral case.
In practice, we find that the fractional model performs substantially better
than the integral model, according to simulations on real-world social network
data.


title: Uncertainties in MEPS@NLO calculations of h+jets

abstract:
  Uncertainties in the simulation of Higgs boson production with up to two jets
at next-to leading order accuracy are investigated. Traditional uncertainty
estimates based on scale variations are extended employing different functional
forms for the central scale, and the impact of details in the implementation of
the parton shower is discussed.


title:
Predicting the Next Maxima Incidents of the Seasonally Forced SEIR
  Epidemic Model

abstract:
  This paper aims at predicting the next maxima values of the state variables
of the seasonal SEIR epidemic model and their in-between time intervals.
Lorenz's method of analogues is applied on the attractor formed by the maxima
of the corresponding state variables. It is found that both quantities are
characterized by a high degree of predictability in the case of the chaotic
regime of the parameter space.


title: The value of H_0 in the inhomogeneous Universe

abstract:
  Local measurements of the Hubble expansion rate are affected by structures
like galaxy clusters or voids. Here we present a fully relativistic treatment
of this effect, studying how clustering modifies the mean distance
(modulus)-redshift relation and its dispersion in a standard $\Lambda$CDM
universe. The best estimates of the local expansion rate stem from supernova
observations at small redshifts (0.01<z<0.1). It is interesting to compare
these local measurements with global fits to data from cosmic microwave
background anisotropies. In particular, we argue that cosmic variance (i.e. the
effects of the local structure) is of the same order of magnitude as the
current observational errors and must be taken into account in local
measurements of the Hubble expansion rate.


title: Mobility in a strongly coupled dusty plasma with gas

abstract:
  The mobility of a charged projectile in a strongly coupled dusty plasma is
simulated. A net force $F$, opposed by a combination of collisional scattering
and gas friction, causes projectiles to drift at a mobility-limited velocity
$u_p$. The mobility $\mu_p=u_p/F$ of the projectile's motion is obtained. Two
regimes depending on $F$ are identified. In the high force regime, $\mu_p
\propto F^{0.23}$, and the scattering cross section $\sigma_s$ diminishes as
$u_p^{-6/5}$. Results for $\sigma_s$ are compared with those for a weakly
coupled plasma and for two-body collisions in a Yukawa potential. The
simulation parameters are based on microgravity plasma experiments.


title:
Diverse and widespread contamination evident in the unmapped depths of
  high throughput sequencing data

abstract:
  Background: Trace quantities of contaminating DNA are widespread in the
laboratory environment, but their presence has received little attention in the
context of high throughput sequencing. This issue is highlighted by recent
works that have rested controversial claims upon sequencing data that appear to
support the presence of unexpected exogenous species.
  Results: I used reads that preferentially aligned to alternate genomes to
infer the distribution of potential contaminant species in a set of independent
sequencing experiments. I confirmed that dilute samples are more exposed to
contaminating DNA, and, focusing on four single-cell sequencing experiments,
found that these contaminants appear to originate from a wide diversity of
clades. Although negative control libraries prepared from "blank" samples
recovered the highest-frequency contaminants, low-frequency contaminants, which
appeared to make heterogeneous contributions to samples prepared in parallel
within a single experiment, were not well controlled for. I used these results
to show that, despite heavy replication and plausible controls, contamination
can explain all of the observations used to support a recent claim that
complete genes pass from food to human blood.
  Conclusions: Contamination must be considered a potential source of signals
of exogenous species in sequencing data, even if these signals are replicated
in independent experiments, vary across conditions, or indicate a species which
seems a priori unlikely to contaminate. Negative control libraries processed in
parallel are essential to control for contaminant DNAs, but their limited
ability to recover low-frequency contaminants must be recognized.


title: Contributing to TAI with a Secondary Representation of the SI Second

abstract:
  We report the first contribution to the international atomic time (TAI) based
on a secondary representation of the SI second. This work is done with the
LNE-SYRTE FO2-Rb fountain frequency standard using the $^{87}$Rb ground state
hyperfine transition. We describe FO2-Rb and how it is connected to local and
international time scales. We report on local measurements of this frequency
standard in the SI system, i.e. against primary frequency standards, down to a
fractional uncertainty of $4.4\times 10^{-16}$, and on the establishment of the
recommended value for the $^{87}$Rb hyperfine transition by the CIPM. We also
report on the process that led to the participation of the FO2-Rb frequency
standard to $Circular~T$ and to the elaboration of TAI. This participation
enables us to demonstrate absolute frequency measurement directly in terms of
the SI second realized by the TAI ensemble with a statistical uncertainty of
$1.1\times 10^{-16}$, therefore at the limit allowed by the accuracy of primary
frequency standards. This work constitutes a demonstration of how other
secondary representations, based on optical transitions, could also be used for
TAI, and an investigation of a number of issues relevant to a future
redefinition of the SI second.


title:
Notes on higher-spin algebras: minimal representations and structure
  constants

abstract:
  The higher-spin (HS) algebras so far known can be interpreted as the
symmetries of the minimal representation of the isometry algebra. After
discussing this connection briefly, we generalize this concept to any classical
Lie algebras and consider the corresponding HS algebras. For sp(2N) and so(N),
the minimal representations are unique so we get unique HS algebras. For sl(N),
the minimal representation has one-parameter family, so does the corresponding
HS algebra. The so(N) HS algebra is what underlies the Vasiliev theory while
the sl(2) one coincides with the 3D HS algebra hs[lambda]. Finally, we derive
the explicit expression of the structure constant of these algebras --- more
precisely, their bilinear and trilinear forms. Several consistency checks are
carried out for our results.


title:
Type Ia Supernova Rate Measurements to Redshift 2.5 from CANDELS :
  Searching for Prompt Explosions in the Early Universe

abstract:
  The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS)
was a multi-cycle treasury program on the Hubble Space Telescope (HST) that
surveyed a total area of ~0.25 deg^2 with ~900 HST orbits spread across 5
fields over 3 years. Within these survey images we discovered 65 supernovae
(SN) of all types, out to z~2.5. We classify ~24 of these as Type Ia SN (SN Ia)
based on host-galaxy redshifts and SN photometry (supplemented by grism
spectroscopy of 6 SN). Here we present a measurement of the volumetric SN Ia
rate as a function of redshift, reaching for the first time beyond z=2 and
putting new constraints on SN Ia progenitor models. Our highest redshift bin
includes detections of SN that exploded when the universe was only ~3 Gyr old
and near the peak of the cosmic star-formation history. This gives the CANDELS
high-redshift sample unique leverage for evaluating the fraction of SN Ia that
explode promptly after formation (<500 Myr). Combining the CANDELS rates with
all available SN Ia rate measurements in the literature we find that this
prompt SN Ia fraction is fP=0.53 +0.09 -0.10 (stat) +0.10 -0.26 (sys),
consistent with a delay time distribution that follows a simple t^{-1} power
law for all times t>40 Myr. However, a mild tension is apparent between
ground-based low-z surveys and space-based high-z surveys. In both CANDELS and
the sister HST program CLASH, we find a low rate of SN Ia at z>1. This could be
a hint that prompt progenitors are in fact relatively rare, accounting for only
~20% of all SN Ia explosions -- though further analysis and larger samples will
be needed to examine that suggestion.


title: On the index-conjecture on the length four minimal zero-sum sequences

abstract:
  Let $G$ be a finite cyclic group. Every sequence $S$ over $G$ can be written
in the form $S=(n_1g)\cdot...\cdot(n_lg)$ where $g\in G$ and
$n_1,\cdots,n_l\in[1,{\hbox{\rm ord}}(g)]$, and the index $\ind(S)$ of $S$ is
defined to be the minimum of $(n_1+\cdots+n_l)/\hbox{\rm ord}(g)$ over all
possible $g\in G$ such that $\langle g\rangle=G$. A conjecture says that if $G$
is finite such that $\gcd(|G|,6)=1$, then $\ind(S)=1$ for every minimal
zero-sum sequence $S$. In this paper, we prove that the conjecture holds if $S$
is reduced and at least one $n_i$ coprime to $|G|$.


title: Ising model conformal boundary conditions from open string field theory

abstract:
  Given a consistent choice of conformally invariant boundary conditions in a
two dimensional conformal field theory, one can construct new consistent
boundary conditions by deforming with a relevant boundary operator and flowing
to the infrared, or by a marginal deformation. Open string field theory
provides a very universal tool to discover and study such new boundary
theories. Surprisingly, it also allows one to go in the reverse direction and
to uncover solutions with higher boundary entropy. We will illustrate our
results on the well studied example of Ising model.


title: On the index-conjecture of length four minimal zero-sum sequences II

abstract:
  Let $G$ be a finite cyclic group. Every sequence $S$ over $G$ can be written
in the form $S=(n_1g)\cdot...\cdot(n_lg)$ where $g\in G$ and
$n_1,\cdots,n_l\in[1,{\hbox{\rm ord}}(g)]$, and the index $\ind S$ of $S$ is
defined to be the minimum of $(n_1+\cdots+n_l)/\hbox{\rm ord}(g)$ over all
possible $g\in G$ such that $\langle g\rangle=G$. A conjecture says that if $G$
is finite such that $\gcd(|G|,6)=1$, then $\ind(S)=1$ for every minimal
zero-sum sequence $S$. In this paper, we prove that the conjecture holds if $S$
is reduced and the (A1) condition is satisfied(see [19]).


title: Complex saddle points in QCD at finite temperature and density

abstract:
  The sign problem in QCD at finite temperature and density leads naturally to
the consideration of complex saddle points of the action or effective action.
The global symmetry $\mathcal{CK}$ of the finite-density action, where
$\mathcal{C}$ is charge conjugation and $\mathcal{K}$ is complex conjugation,
constrains the eigenvalues of the Polyakov loop operator $P$ at a saddle point
in such a way that the action is real at a saddle point, and net color charge
is zero. The values of $Tr_{F}P$ and $Tr_{F}P^{\dagger}$ at the saddle point,
are real but not identical, indicating the different free energy cost
associated with inserting a heavy quark versus an antiquark into the system. At
such complex saddle points, the mass matrix associated with Polyakov loops may
have complex eigenvalues, reflecting oscillatory behavior in color-charge
densities. We illustrate these properties with a simple model which includes
the one-loop contribution of gluons and massless quarks moving in a constant
Polyakov loop background. Confinement-deconfinement effects are modeled
phenomenologically via an added potential term depending on the Polyakov loop
eigenvalues. For sufficiently large $T$ and $\mu$, the results obtained reduce
to those of perturbation theory at the complex saddle point. These results may
be experimentally relevant for the CBM experiment at FAIR.


title: Teleportation with Multiple Accelerated Partners

abstract:
  As the current revolution in communication is underway, quantum teleportation
can increase the level of security in quantum communication applications. In
this paper, we present a quantum teleportation procedure that capable to
teleport either accelerated or non-accelerated information through different
quantum channels. These quantum chan- nels are based on accelerated multi-qubit
states, where each qubit of each of these channels represent a partner. Namely,
these states are the the W state, Greenberger-Horne-Zeilinger (GHZ) state, and
the GHZ-like state. Here, we show that the fidelity of teleporting acceler-
ated information is higher than the fidelity of teleporting non-accelerated
information, both through a quantum channel that is based on accelerated state.
Also, the comparison among the performance of these three channels shows that
the degree of fidelity depends on type of the used channel, type of the
measurement, and value of the acceleration. The result of comparison concludes
that teleporting information through channel that is based on the GHZ state is
more robust than teleporting information through channels that are based on the
other two states. For future work, the proposed procedure can be generalized
later to achieve communication through a wider quantum network.


title:
Measurements with STEREO/COR1 data of drag forces acting on small-scale
  blobs falling in the intermediate corona

abstract:
  In this work we study the kinematics of three small-scale (0.01 R$_\odot$)
blobs of chromospheric plasma falling back to the Sun after the huge eruptive
event of June 7, 2011. From a study of 3-D trajectories of blobs made with the
Solar TErrestrial RElations Observatory (STEREO) data, we demonstrate the
existence of a significant drag force acting on the blobs and calculate two
drag coefficients, in the radial and tangential directions. The resulting drag
coefficients $C_D$ are between 0 and 5, comparable in the two directions,
making the drag force only a factor of 0.45-0.75 smaller than the gravitational
force. To obtain a correct determination of electron densities in the blobs, we
also demonstrate how, by combining measurements of total and polarized
brightness, the H$\alpha$ contribution to the white-light emission observed by
the COR1 telescopes can be estimated. This component is significant for
chromospheric plasma, being between 95 and 98 % of the total white-light
emission. Moreover, we demonstrate that the COR1 data can be employed even to
estimate the H$\alpha$ polarized component, which turns out to be in the order
of a few percent of H$\alpha$ total emission from the blobs. If the drag forces
acting on small-scale blobs reported here are similar to those that play a role
during the CME propagation, our results suggest that the magnetic drag should
be considered even in the CME initiation modelling.


title:
Properties of Liquid Clusters in Large-scale Molecular Dynamics
  Nucleation Simulations

abstract:
  We have performed large-scale Lennard-Jones molecular dynamics simulations of
homogeneous vapor-to-liquid nucleation, with $10^9$ atoms. This large number
allows us to resolve extremely low nucleation rates, and also provides
excellent statistics for cluster properties over a wide range of cluster sizes.
The nucleation rates, cluster growth rates, and size distributions are
presented in Diemand et al. [J. Chem. Phys. {\bf 139}, 74309 (2013)], while
this paper analyses the properties of the clusters. We explore the cluster
temperatures, density profiles, potential energies and shapes. A thorough
understanding of the properties of the clusters is crucial to the formulation
of nucleation models. Significant latent heat is retained by stable clusters,
by as much as $\Delta kT = 0.1 \epsilon$ for clusters with size $i = 100$. We
find that the clusters deviate remarkably from spherical - with ellipsoidal
axis ratios for critical cluster sizes typically within $b/c = 0.7\pm 0.05$ and
$a/c = 0.5 \pm 0.05$. We examine cluster spin angular momentum, and find that
it plays a negligible role in the cluster dynamics. The interfaces of large,
stable clusters are thiner than planar equilibrium interfaces by $10-30\%$. At
the critical cluster size, the cluster central densities are between $5-30\%$
lower than the bulk liquid expectations. These lower densities imply
larger-than-expected surface areas, which increase the energy cost to form a
surface, which lowers nucleation rates.


title:
Interpreting Short Gamma Ray Burst Progenitor Kicks and Time Delays
  Using the Host Galaxy-Dark Matter Halo Connection

abstract:
  Nearly 20% of short gamma-ray bursts (sGRBs) have no observed host galaxies.
Combining this finding with constraints on galaxies' dark matter halo potential
wells gives strong limits on the natal kick velocity distribution for sGRB
progenitors. For the best-fitting velocity distribution, one in five sGRB
progenitors receives a natal kick above 150 km/s, consistent with merging
neutron star models but not with merging white dwarf binary models. This
progenitor model constraint is robust to a wide variety of systematic
uncertainties, including the sGRB progenitor time-delay model, the Swift
redshift sensitivity, and the shape of the natal kick velocity distribution. We
also use constraints on the galaxy-halo connection to determine the host halo
and host galaxy demographics for sGRBs, which match extremely well with
available data. Most sGRBs are expected to occur in halos near 10^12 Msun and
in galaxies near 5x10^10 Msun (L_*); unobserved faint and high-redshift host
galaxies contribute a small minority of the observed hostless sGRB fraction. We
find that sGRB redshift distributions and host galaxy stellar masses weakly
constrain the progenitor time-delay model; the active vs. passive fraction of
sGRB host galaxies may offer a stronger constraint. Finally, we discuss how
searches for gravitational wave optical counterparts in the local Universe can
reduce followup times using these findings.


title: The magnetic field at milliarcsecond resolution around IRAS20126+4104

abstract:
  IRAS20126+4104 is a well studied B0.5 protostar that is surrounded by a ~1000
au Keplerian disk and is where a large-scale outflow originates. Both 6.7-GHz
CH3OH masers and 22-GHz H2O masers have been detected toward this young stellar
object. The CH3OH masers trace the Keplerian disk, while the H2O masers are
associated with the surface of the conical jet. Recently, observations of dust
polarized emission (350 um) at an angular resolution of 9 arcseconds (~15000
au) have revealed an S-shaped morphology of the magnetic field around
IRAS20126+4104. The observations of polarized maser emissions at milliarcsecond
resolution (~20 au) can make a crucial contribution to understanding the
orientation of the magnetic field close to IRAS20126+4104. This will allow us
to determine whether the magnetic field morphology changes from arcsecond
resolution to milliarcsecond resolution. The European VLBI Network was used to
measure the linear polarization and the Zeeman splitting of the 6.7-GHz CH3OH
masers toward IRAS20126+4104. The NRAO Very Long Baseline Array was used to
measure the linear polarization and the Zeeman splitting of the 22-GHz H2O
masers toward the same region. We detected 26 CH3OH masers and 5 H2O masers at
high angular resolution. Linear polarization emission was observed toward three
CH3OH masers and toward one H2O maser. Significant Zeeman splitting was
measured in one CH3OH maser (\Delta V_{Z}=-9.2 +/- 1.4 m/s). No significant (5
sigma) magnetic field strength was measured using the H2O masers. We found that
in IRAS20126+4104 the rotational energy is less than the magnetic energy.


title:
Prospects for measuring supermassive black hole masses with future
  extremely large telescopes

abstract:
  The next generation of giant-segmented mirror telescopes ($>$ 20 m) will
enable us to observe galactic nuclei at much higher angular resolution and
sensitivity than ever before. These capabilities will introduce a revolutionary
shift in our understanding of the origin and evolution of supermassive black
holes by enabling more precise black hole mass measurements in a mass range
that is unreachable today. We present simulations and predictions of the
observations of nuclei that will be made with the Thirty Meter Telescope (TMT)
and the adaptive optics assisted integral-field spectrograph IRIS, which is
capable of diffraction-limited spectroscopy from $Z$ band (0.9 $\mu$m) to $K$
band (2.2 $\mu$m). These simulations, for the first time, use realistic values
for the sky, telescope, adaptive optics system, and instrument, to determine
the expected signal-to-noise ratio of a range of possible targets spanning
intermediate mass black holes of $\sim10^4$ \msun to the most massive black
holes known today of $>10^{10}$ $M_\odot$. We find that IRIS will be able to
observe Milky Way-mass black holes out the distance of the Virgo cluster, and
will allow us to observe many more brightest cluster galaxies where the most
massive black holes are thought to reside. We also evaluate how well the
kinematic moments of the velocity distributions can be constrained at the
different spectral resolutions and plate scales designed for IRIS. We find that
a spectral resolution of $\sim8000$ will be necessary to measure the masses of
intermediate mass black holes. By simulating the observations of galaxies found
in SDSS DR7, we find that over $10^5$ massive black holes will be observable at
distances between $0.005 < z < 0.18$ with the estimated sensitivity and angular
resolution provided by access to $Z$-band (0.9 $\mu$m) spectroscopy from IRIS
and the TMT adaptive optics system. (Abridged)


title:
Spontaneous R-Parity Breaking, Stop LSP Decays and the Neutrino Mass
  Hierarchy

abstract:
  The MSSM with right-handed neutrino supermultiplets, gauged B-L symmetry and
a non-vanishing sneutrino expectation value is the minimal theory that
spontaneously breaks R-parity and is consistent with the bounds on proton
stability and lepton number violation. This minimal B-L MSSM can have a
colored/charged LSP, of which a stop LSP is the most amenable to observation at
the LHC. We study the R-parity violating decays of a stop LSP into a bottom
quark and charged leptons--the dominant modes for a generic "admixture" stop. A
numerical analysis of the relative branching ratios of these decay channels is
given using a wide scan over the parameter space. The fact that R-parity is
violated in this theory by a vacuum expectation value of a sneutrino links
these branching ratios directly to the neutrino mass hierarchy. It is shown how
a discovery of bottom-charged lepton events at the LHC can potentially
determine whether the neutrino masses are in a normal or inverted hierarchy, as
well as determining the theta_23 neutrino mixing angle. Finally, present LHC
bounds on these leptoquark signatures are used to put lower bounds on the stop
mass.


title:
Gravitational Lens Recovery with GLASS: Measuring the mass profile and
  shape of a lens

abstract:
  We use a new non-parametric gravitational modelling tool -- \Glass{} -- to
determine what quality of data (strong lensing, stellar kinematics, and/or
stellar masses) are required to measure the circularly averaged mass profile of
a lens and its shape. \Glass{} uses an under-constrained adaptive grid of mass
pixels to model the lens, searching through thousands of models to marginalise
over model uncertainties. Our key findings are as follows: (i) for pure lens
data, multiple sources with wide redshift separation give the strongest
constraints as this breaks the well-known mass-sheet or steepness degeneracy;
(ii) a single quad with time delays also performs well, giving a good recovery
of both the mass profile and its shape; (iii) stellar masses -- for lenses
where the stars dominate the central potential -- can also break the steepness
degeneracy, giving a recovery for doubles almost as good as having a quad with
time delay data, or multiple source redshifts; (iv) stellar kinematics provide
a robust measure of the mass at the half light radius of the stars $r_{1/2}$
that can also break the steepness degeneracy if the Einstein radius $r_E \neq
r_{1/2}$; and (v) if $r_E \sim r_{1/2}$, then stellar kinematic data can be
used to probe the stellar velocity anisotropy $\beta$ -- an interesting
quantity in its own right. Where information on the mass distribution from
lensing and/or other probes becomes redundant, this opens up the possibility of
using strong lensing to constrain cosmological models.


title: Non-Trivial Checks of Novel Consistency Relations

abstract:
  Single-field perturbations satisfy an infinite number of consistency
relations constraining the squeezed limit of correlation functions at each
order in the soft momentum. These can be understood as Ward identities for an
infinite set of residual global symmetries, or equivalently as Slavnov-Taylor
identities for spatial diffeomorphisms. In this paper, we perform a number of
novel, non-trivial checks of the identities in the context of slow-roll single
field inflationary models with arbitrary sound speed. We focus for concreteness
on identities involving 3-point functions with a soft external mode, and
consider all possible scalar and tensor combinations for the hard-momentum
modes. In all these cases, we check the consistency relations up to and
including cubic order in the soft momentum. For this purpose, we compute for
the first time the 3-point functions involving 2 scalars and 1 tensor, as well
as 2 tensors and 1 scalar, for arbitrary sound speed.


title: Super-Sample CMB Lensing

abstract:
  Lensing of the CMB by modes that are larger than the size of the survey
dilates intrinsic scales in the temperature and polarization fields and
coherently shifts their observed power spectra with respect to the ensemble or
all-sky mean. The effect can be simply encapsulated as a contribution to the
power spectrum covariance matrix in accordance with the lensing trispectrum or
as an additional parameter, the mean convergence in the field, for parameter
estimation. It should be included for upcoming surveys that precisely measure
acoustic polarization features deep into the damping tail at multipoles of
$\ell \gtrsim 1500$ with less than $10\%$ of sky. Its omission may lead to
seemingly conflicting values for the angular scale of the sound horizon which
may then provide erroneous cosmological parameters when compared to baryon
acoustic oscillation measurements.


title:
Scale-invariant hyperscaling-violating holographic theories and the
  resistivity of strange metals with random-field disorder

abstract:
  We compute the direct current resistivity of a scale-invariant,
$d$-dimensional strange metal with dynamic critical exponent $z$ and
hyperscaling-violating exponent $\theta$, weakly perturbed by a scalar operator
coupled to random-field disorder that locally breaks a $\mathbb{Z}_2$ symmetry.
Independent calculations via Einstein-Maxwell-Dilaton holography and memory
matrix methods lead to the same results. We show that random field disorder has
a strong effect on resistivity: charge carriers in the infrared are easily
depleted, as the relaxation time for momentum is surprisingly small. In the
course of our holographic calculation we use a non-trivial dilaton coupling to
the disordered scalar, allowing us to study a strongly-coupled scale invariant
theory with $\theta \ne 0$. Using holography, we are also able to determine the
disorder strength at which perturbation theory breaks down. Curiously, for
locally critical theories this breakdown occurs when the resistivity is
proportional to the entropy density, up to a possible logarithmic correction.


title: An improved model of HII bubbles during the epoch of reionization

abstract:
  The size distribution of ionized regions during the epoch of reionization --
a key ingredient in understanding the HI power spectrum observable by 21cm
experiments -- can be modelled analytically using the excursion set formalism
of random walks in the smoothed initial density field. To date, such
calculations have been based on simplifying assumptions carried forward from
the earliest excursion set models of two decades ago. In particular, these
models assume that the random walks have uncorrelated steps and that haloes can
form at arbitrary locations in the initial density field. We extend these
calculations by incorporating recent technical developments that allow us to
(a) include the effect of correlations in the steps of the walks induced by a
realistic smoothing filter and (b) more importantly, account for the fact that
dark matter haloes preferentially form near peaks in the initial density. A
comparison with previous calculations shows that including these features,
particularly the peaks constraint on halo locations, has large effects on the
size distribution of the HII bubbles surrounding these haloes. For example,
when comparing models at the same value of the globally averaged ionized volume
fraction, the typical bubble sizes predicted by our model are more than a
factor 2 larger than earlier calculations. Our results can potentially have a
significant impact on estimates of the observable HI power spectrum.


title:
Measuring mass-loss rates and constraining shock physics using X-ray
  line profiles of O stars from the Chandra archive

abstract:
  We quantitatively investigate the extent of wind absorption signatures in the
X-ray grating spectra of all non-magnetic, effectively single O stars in the
Chandra archive via line profile fitting. Under the usual assumption of a
spherically symmetric wind with embedded shocks, we confirm previous claims
that some objects show little or no wind absorption. However, many other
objects do show asymmetric and blue shifted line profiles, indicative of wind
absorption. For these stars, we are able to derive wind mass-loss rates from
the ensemble of line profiles, and find values lower by an average factor of 3
than those predicted by current theoretical models, and consistent with H-alpha
if clumping factors of f_cl ~ 20 are assumed. The same profile fitting
indicates an onset radius of X-rays typically at r ~ 1.5 R_star, and terminal
velocities for the X-ray emitting wind component that are consistent with that
of the bulk wind. We explore the likelihood that the stars in the sample that
do not show significant wind absorption signatures in their line profiles have
at least some X-ray emission that arises from colliding wind shocks with a
close binary companion. The one clear exception is zeta Oph, a weak-wind star
that appears to simply have a very low mass-loss rate. We also reanalyse the
results from the canonical O supergiant zeta Pup, using a solar-metallicity
wind opacity model and find Mdot = 1.8 \times 10^{-6} M_sun/yr, consistent with
recent multi-wavelength determinations.


title:
$\psi$-epistemic models are exponentially bad at explaining the
  distinguishability of quantum states

abstract:
  The status of the quantum state is perhaps the most controversial issue in
the foundations of quantum theory. Is it an epistemic state (state of
knowledge) or an ontic state (state of reality)? In realist models of quantum
theory, the epistemic view asserts that nonorthogonal quantum states correspond
to overlapping probability measures over the true ontic states. This naturally
accounts for a large number of otherwise puzzling quantum phenomena. For
example, the indistinguishability of nonorthogonal states is explained by the
fact that the ontic state sometimes lies in the overlap region, in which case
there is nothing in reality that could distinguish the two states. For this to
work, the amount of overlap of the probability measures should be comparable to
the indistinguishability of the quantum states. In this letter, I exhibit a
family of states for which the ratio of these two quantities must be $\leq
2de^{-cd}$ in Hilbert spaces of dimension $d$ that are divisible by $4$. This
implies that, for large Hilbert space dimension, the epistemic explanation of
indistinguishability becomes implausible at an exponential rate as the Hilbert
space dimension increases.


title: Relative Thermalization

abstract:
  When studying thermalization of quantum systems, it is typical to ask whether
a system interacting with an environment will evolve towards a local thermal
state. Here, we show that a more general and relevant question is "when does a
system thermalize relative to a particular reference?" By relative
thermalization we mean that, as well as being in a local thermal state, the
system is uncorrelated with the reference. We argue that this is necessary in
order to apply standard statistical mechanics to the study of the interaction
between a thermalized system and a reference. We then derive a condition for
relative thermalization of quantum systems interacting with an arbitrary
environment. This condition has two components: the first is state-independent,
reflecting the structure of invariant subspaces, like energy shells, and the
relative sizes of system and environment; the second depends on the initial
correlations between reference, system and environment, measured in terms of
conditional entropies. Intuitively, a small system interacting with a large
environment is likely to thermalize relative to a reference, but only if,
initially, the reference was not highly correlated with the system and
environment. Our statement makes this intuition precise, and we show that in
many natural settings this thermalization condition is approximately tight.
Established results on thermalization, which usually ignore the reference,
follow as special cases of our statements.


title: Orbital Dynamics of Multi-Planet Systems with Eccentricity Diversity

abstract:
  Since exoplanets were detected using the radial velocity method, they have
revealed a diverse distribution of orbital configurations. Amongst these are
planets in highly eccentric orbits (e > 0.5). Most of these systems consist of
a single planet but several have been found to also contain a longer period
planet in a near-circular orbit. Here we use the latest Keplerian orbital
solutions to investigate four known systems which exhibit this extreme
eccentricity diversity; HD 37605, HD 74156, HD 163607, and HD 168443. We place
limits on the presence of additional planets in these systems based on the
radial velocity residuals. We show that the two known planets in each system
exchange angular momentum through secular oscillations of their eccentricities.
We calculate the amplitude and timescale for these eccentricity oscillations
and associated periastron precession. We further demonstrate the effect of
mutual orbital inclinations on the amplitude of high-frequency eccentricity
oscillations. Finally, we discuss the implications of these oscillations in the
context of possible origin scenarios for unequal eccentricities.


title:
Perturbative expansion of the plaquette to ${\cal O}(\alpha^{35})$ in
  four-dimensional SU(3) gauge theory

abstract:
  Using numerical stochastic perturbation theory, we determine the first 35
infinite volume coefficients of the perturbative expansion in powers of the
strong coupling constant $\alpha$ of the plaquette in SU(3) gluodynamics. These
coefficients are obtained in lattice regularization with the standard Wilson
gauge action. The on-set of the dominance of the dimension four renormalon
associated to the gluon condensate is clearly observed. We determine the
normalization of the corresponding singularity in the Borel plane and convert
this into the $\overline{\mathrm{MS}}$ scheme. We also comment on the impact of
the renormalon on non-perturbative determinations of the gluon condensate.


title: Faster Communication Using Probabilistic Swapped-Bell-States Analysis

abstract:
  In this article, a procedure called Probabilistic Swapped-Bell-States
Analysis (PSBA) is proposed. Using this procedure two communication partners
can transmit (binary-encoded) information over large spatial distances. This
procedure is unusual insofar as no classical communication channels are used
either during or after information encoding. To make this possible,
entanglement swapping is used as a transport channel. The encoding of bits is
realized by the execution (or non-execution, as the case may be) of
entanglement swapping on multiple photon pairs, while decoding is realized by a
statistical detection of swapped entanglements. If the PSBA procedure sustains
itself against a rebuttal by the scientific community, it would constitute a
technical approach for transmitting information faster than light. The PSBA
procedure seems to be in harmony with the no-communication theorem, since PSBA
does not manipulate (and teleport) specific states from one (entangled)
particle to another in order to communicate, but instead uses statistics on
entanglement swappings for information encoding.


title: Mixing in Magnetized Turbulent Media

abstract:
  Turbulent motions are essential to the mixing of entrained fluids and are
also capable of amplifying weak initial magnetic fields by small-scale dynamo
action. Here we perform a systematic study of turbulent mixing in magnetized
media, using three-dimensional magnetohydrodynamic simulations that include a
scalar concentration field. We focus on how mixing depends on the magnetic
Prandtl number, Pm, from 1 to 4 and the Mach number, M}, from 0.3 to 2.4. For
all subsonic flows, we find that the velocity power spectrum has a k^-5/3 slope
in the early, kinematic phase, but steepens due to magnetic back reactions as
the field saturates. The scalar power spectrum, on the other hand, flattens
compared to k^-5/3 at late times, consistent with the Obukohov-Corrsin picture
of mixing as a cascade process. At higher Mach numbers, the velocity power
spectrum also steepens due to the presence of shocks, and the scalar power
spectrum again flattens accordingly. Scalar structures are more intermittent
than velocity structures in subsonic turbulence while for supersonic
turbulence, velocity structures appear more intermittent than the scalars only
in the kinematic phase. Independent of the Mach number of the flow, scalar
structures are arranged in sheets in both the kinematic and saturated phases of
the magnetic field evolution. For subsonic turbulence, scalar dissipation is
hindered in the strong magnetic field regions, probably due to Lorentz forces
suppressing the buildup of scalar gradients, while for supersonic turbulence,
scalar dissipation increases monotonically with increasing magnetic field
strength. At all Mach numbers, mixing is significantly slowed by the presence
of dynamically-important small-scale magnetic fields, implying that mixing in
the interstellar medium and in galaxy clusters is less efficient than modeled
in hydrodynamic simulations.


title: Modified Chaplygin Gas Cosmology with Bulk Viscosity

abstract:
  In this paper, we investigate the viscous modified Chaplygin gas cosmological
model. Solutions for different values of the viscosity parameter are obtained
using both analytical and numerical methods. We have calculated the
deceleration and defined {\em newly} statefinder $\{r, s \}$ pair in D
dimensions. It is shown that when $D=4$, the usual statefinder parameters are
recovered. Furthermore, we apply the statefinder diagnostic to the MCG model
with and without viscosity in $D$ dimensions and explore these parameters
graphically.


title: Counting commensurability classes of hyperbolic manifolds

abstract:
  Gromov and Piatetski-Shapiro proved existence of finite volume non-arithmetic
hyperbolic manifolds of any given dimension. In dimension four and higher, we
show that there are about v^v such manifolds of volume at most v, considered up
to commensurability. Since the number of arithmetic ones tends to be
polynomial, almost all hyperbolic manifolds are non-arithmetic in an
appropriate sense. Our method involves a geometric graph-of-spaces construction
that relies on arithmetic properties of certain quadratic forms.


title:
A minimum control ancilla driven quantum computation scheme with
  repeat-until-success style gate generation

abstract:
  Some two qubit interactions are singly sufficient for universal quantum
computation but not without the use of an ancilla. Recent schemes for universal
quantum computation have focused on hybrid physical systems using ancillae. In
them, the application of resources is shifted to the ancilla system. We
consider which 2-qubit interactions are universal in ancilla schemes where
direct connections between main register qubits are forbidden. By the use of
ancilla driven operations and repeat-until-success style random gates, a single
fixed symmetric gate can be universal be control of the number of repetitions
alone.


title:
Best Approximation from the Kuhn-Tucker Set of Composite Monotone
  Inclusions

abstract:
  Kuhn-Tucker points play a fundamental role in the analysis and the numerical
solution of monotone inclusion problems, providing in particular both primal
and dual solutions. We propose a class of strongly convergent algorithms for
constructing the best approximation to a reference point from the set of
Kuhn-Tucker points of a general Hilbertian composite monotone inclusion
problem. Applications to systems of coupled monotone inclusions are presented.
Our framework does not impose additional assumptions on the operators present
in the formulation, and it does not require knowledge of the norm of the linear
operators involved in the compositions or the inversion of linear operators.


title: Enumeration of $2$-Polymatroids on up to Seven Elements

abstract:
  A theory of single-element extensions of integer polymatroids analogous to
that of matroids is developed. We present an algorithm to generate a catalog of
$2$-polymatroids, up to isomorphism. When we implemented this algorithm on a
computer, obtaining all $2$-polymatroids on at most seven elements, we
discovered the surprising fact that the number of $2$-polymatroids on seven
elements fails to be unimodal in rank.


title:
The effect of incident angle of pumping light on Cholesteric Liquid
  Crystal tunable laser wavelength

abstract:
  One notable feature of dye doped cholesteric liquid crystal is the variation
of pitch and refractive index as the incidence angle of the pumping light
shifts. Based on this feature, this paper studies the effects of pumping
light's incidence angle on emission properties of the dye doped cholesteric
liquid crystal tunable laser. First, we investigated the relationship among the
concentration of chiral reagent, the incidence angle of the pumping light, and
the pitch of liquid-crystal display (LCD); then we made a tunable-wavelength
laser and pumped the prepared sample with 532nm laser outputted from the Nd:
YAG multi-frequency pulse laser. As the incident angle of the pumping light
shifts between 20 {\deg} ~ 90 {\deg}, the tuning range of the wavelength
emitted by the laser reaches 10.73nm, ranging between 647.38nm and 658.11nm.


title: Support vector comparison machines

abstract:
  In ranking problems, the goal is to learn a ranking function from labeled
pairs of input points. In this paper, we consider the related comparison
problem, where the label indicates which element of the pair is better, or if
there is no significant difference. We cast the learning problem as a margin
maximization, and show that it can be solved by converting it to a standard
SVM. We use simulated nonlinear patterns, a real learning to rank sushi data
set, and a chess data set to show that our proposed SVMcompare algorithm
outperforms SVMrank when there are equality pairs.


title: The H$_2^+$ molecular ion: low-lying states

abstract:
  Matching for a wavefunction the WKB expansion at large distances and Taylor
expansion at small distances leads to a compact, few-parametric uniform
approximation found in {\it J. Phys. B44, 101002 (2011)}. The ten low-lying
eigenstates of H$_2^+$ of the quantum numbers $(n,m,\La,\pm)$\, with $n=m=0$ at
$\La=0,1,2$, with $n=1$, $m=0$ and $n=0$, $m=1$ at $\La=0$ of both parities are
explored for all interproton distances $R$. For all these states this
approximation provides the relative accuracy $\lesssim 10^{-5}$ (not less than
5 s.d.) locally, for any real coordinate $x$ in eigenfunctions, when for total
energy $E(R)$ it gives 10-11 s.d. for $R \in [0,50]$~a.u. Corrections to the
approximation are evaluated in the specially-designed, convergent perturbation
theory. Separation constants are found with not less than 8 s.d. The oscillator
strength for the electric dipole transitions $E1$ is calculated with not less
than 6~s.d. A dramatic dip in the $E1$ oscillator strength
$f_{1s\si_g-3p\si_u}$ at $R \sim R_{eq}$ is observed. The magnetic dipole and
electric quadrupole transitions are calculated for the first time with not less
than 6~s.d. in oscillator strength. For two lowest states $(0,0,0,\pm)$ (or,
equivalently, $1s\si_g$ and $2p\si_u$ states) the potential curves are checked
and confirmed in the Lagrange mesh method within 12~s.d. Based on them the
Energy Gap between $1s\si_g$ and $2p\si_u$ potential curves is approximated
with modified Pade $R e^{-R} [Pade(8/7)](R)$ with not less than 4-5 figures at
$R \in [0, 40]$\,a.u. Sum of potential curves $E_{1s\si_g} + E_{2p\si_u}$ is
approximated by Pade $1/R [Pade(5/8)](R)$ in $R \in [0, 40]$\,a.u. with not
less than {3-4} figures.


title: Spin-1 Hopfield model under a random field

abstract:
  The goal of the present work is to investigate the role of trivial disorder
and nontrivial disorder in the three-state Hopfield model under a Gaussian
random field. In order to control the nontrivial disorder, the Hebb interaction
is used. This provides a way to control the system frustration by means of the
parameter a=p/N, varying from trivial randomness to a highly frustrated regime,
in the thermodynamic limit. We performed the thermodynamic analysis using the
one-step replica-symmetry-breaking mean field theory to obtain the order
parameters and phase diagrams for several strengths of a, the anisotropy
constant, and the random field.


title:
Finite field restriction estimates based on Kakeya maximal operator
  estimates

abstract:
  In the finite field setting, we show that the restriction conjecture
associated to any one of a large family of $d=2n+1$ dimensional quadratic
surfaces implies the $n+1$ dimensional Kakeya conjecture (Dvir's theorem). This
includes the case of the paraboloid over finite fields in which $-1$ \emph{is}
a square. We are able to partially reverse this implication using the sharp
Kakeya maximal operator estimates of Ellenberg, Oberlin and Tao to establish
the first finite field restriction estimates beyond the Stein-Tomas exponent in
this setting.


title:
Regular variation of infinite series of processes with random
  coefficients

abstract:
  In this article, we consider a series $X(t)=\sum_{j \geq 1}\Psi_j(t) Z_j(t),t
\in [0,1]$ of random processes with sample paths in the space $D=D[0,1]$ of
c\`adl\`ag functions (i.e. right-continuous functions with left limits) on
$[0,1]$. We assume that $(Z_j)_{j \geq 1}$ are i.i.d. processes with sample
paths in $D$ and $(\Psi_j)_{j \geq 1}$ are processes with continuous sample
paths. Using the notion of regular variation for $D$-valued random elements
(introduced in Hult and Lindskog (2005)), we show that $X$ is regularly varying
if $Z_1$ is regularly varying, $(\Psi_j)_{j \geq 1}$ satisfy some moment
conditions, and a certain ``predictability assumption'' holds for the sequence
$\{(Z_j,\Psi_j)\}_{j \geq 1}$. Our result can be viewed as an extension of
Theorem 3.1 of Hult and Samorodnitsky (2008) from random vectors in $R^d$ to
random elements in $D$. As a preliminary result, we prove a version of
Breiman's lemma for $D$-valued random elements, which can be of independent
interest.


title:
Stochastic Interactions of Two Brownian Hard Spheres in the Presence of
  Depletants

abstract:
  A quantitative analysis is presented for the stochastic interactions of a
pair of Brownian hard spheres in non-adsorbing polymer solutions. The hard
spheres are hypothetically trapped by optical tweezers and allowed for random
motion near the trapped positions. The investigation focuses on the long-time
correlated Brownian motion. The mobility tensor altered by the polymer
depletion effect is computed by the boundary integral method, and the
corresponding random displacement is determined by the fluctuation-dissipation
theorem. From our computations it follows that the presence of depletion layers
around the hard spheres has a significant effect on the hydrodynamic
interactions and particle dynamics as compared to pure solvent and pure polymer
solution (no depletion) cases. The probability distribution functions of random
walks of the two interacting hard spheres that are trapped clearly shifts due
to the polymer depletion effect. The results show that the reduction of the
viscosity in the depletion layers around the spheres and the entropic force due
to the overlapping of depletion zones have a significant influence on the
correlated Brownian interactions.


title: The distance ratio metric on some parts of $\mathbb C$ plane

abstract:
  We prove a generalization for some $\mathbb C$ domains of Gehring - Palka
theorem on Moebius transformations regarding the distance ratio metric. Namely,
we show that this theorem is valid for arbitrary holomorphic mappings $f : H
\to H$ or $f : D \to D$ with the same Lipschitz constant $2$.


title:
Invariant subspaces of algebras of analytic elements associated with
  periodic flows on W*-algebras

abstract:
  We consider an action of the circle group, T on a von Neumann algebra, M.
Similarly to the case when the algebra of essentially bounded functions on T is
acted upon by translations, we define the generalized Hardy subspace of H,where
H is the Hilbert space of a standard representation of M and the subalgebra of
analytic elements of M with respect to the action. We prove that the subalgebra
of analytic elements is a reflexive algebra of operators if the Arveson
spectrum is finite or, if the spectrum is infinite, the spectral subspace
corresponding to the least positive element contains an unitary operator. We
also prove that the analytic algebra is reflexive if M is an abelian
W*-algebra. Examples include the algebra of analytic Toeplitz operators,
crossed products, reduced semicrossed products and some reflexive nest
subalgebras of von Neumann algebras.


title: Is the Milky Way's Hot Halo Convectively Unstable?

abstract:
  We investigate the convective stability of two popular types of model of the
gas distribution in the hot Galactic halo. We first consider models in which
the halo density and temperature decrease exponentially with height above the
disk. These halo models were created to account for the fact that, on some
sight lines, the halo's X-ray emission lines and absorption lines yield
different temperatures, implying that the halo is non-isothermal. We show that
the hot gas in these exponential models is convectively unstable if
$\gamma<3/2$, where $\gamma$ is the ratio of the temperature and density scale
heights. Using published measurements of $\gamma$ and its uncertainty, we use
Bayes' Theorem to infer posterior probability distributions for $\gamma$, and
hence the probability that the halo is convectively unstable for different
sight lines. We find that, if these exponential models are good descriptions of
the hot halo gas, at least in the first few kiloparsecs from the plane, the hot
halo is reasonably likely to be convectively unstable on two of the three sight
lines for which scale height information is available. We also consider more
extended models of the halo. While isothermal halo models are convectively
stable if the density decreases with distance from the Galaxy, a model of an
extended adiabatic halo in hydrostatic equilibrium with the Galaxy's dark
matter is on the boundary between stability and instability. However, we find
that radiative cooling may perturb this model in the direction of convective
instability. If the Galactic halo is indeed convectively unstable, this would
argue in favor of supernova activity in the Galactic disk contributing to the
heating the hot halo gas.


title: Sparse Bayesian Unsupervised Learning

abstract:
  This paper is about variable selection, clustering and estimation in an
unsupervised high-dimensional setting. Our approach is based on fitting
constrained Gaussian mixture models, where we learn the number of clusters $K$
and the set of relevant variables $S$ using a generalized Bayesian posterior
with a sparsity inducing prior. We prove a sparsity oracle inequality which
shows that this procedure selects the optimal parameters $K$ and $S$. This
procedure is implemented using a Metropolis-Hastings algorithm, based on a
clustering-oriented greedy proposal, which makes the convergence to the
posterior very fast.


title:
Viscoelasticity of a colloidal gel during dynamical arrest: evolution
  through the critical gel and comparison with a soft colloidal glass

abstract:
  We consider gelation of colloidal particles in suspension after cessation of
shear flow. Particle aggregation is driven by a temperature-tunable attractive
potential which controls the growth of clusters under isothermal conditions. A
series of frequency resolved time sweeps is used to systematically reconstruct
the frequency dependent dynamic moduli as a function of time and temperature or
attraction strength. The data display typical hallmarks of gelation with an
abrupt transition from a fluid state into a dynamically arrested gel state
after a characteristic gelation time $t_g$ that varies exponentially with
temperature and serves to collapse the evolution of the system onto a universal
curve. We observe the viscoelastic properties of the critical gel where we find
that $G'(\omega)\approxeq G''(\omega)\sim \omega^{n_c}$ where $n_c=0.5$ in a
narrow time window across all attraction strengths. We measure a dynamic
critical exponent of $\kappa=0.25$ which is similar to that observed in
crosslinked polymer gels. The approach to the critical gel is therefore
governed by $\eta_0\sim-\epsilon^{-s}$ and $G_e\sim\epsilon^z$ with $s=z=2$
where $\epsilon=p/p_c-1$ is the distance to the gel point. Remarkably, the
relaxation moduli of the near-critical gels are identical across the
temperatures considered, with $G(t)\approx0.33t^{-0.5}$. This suggests an
underlying strong similarity in gel structure in the regime of attraction
strengths considered, despite the differences in aggregation kinetics. We
contrast these findings with the behavior of a colloidal glass undergoing
dynamical arrest where no critical state is observed and where the arrest time
of the system displays a marked frequency dependence. These findings highlight
the underlying structural differences between colloidal gels and glasses which
are manifest in their dynamic properties in the vicinity of the liquid-to-solid
transition.


title:
Efficient description of strongly correlated electrons with mean-field
  cost

abstract:
  We present an efficient approach to the electron correlation problem that is
well-suited for strongly interacting many-body systems, but requires only
mean-field-like computational cost. %which is based on orbital optimization of
electron pairs. The performance of our approach is illustrated for the
one-dimensional Hubbard model with periodic boundary conditions for different
chain lengths, and for the non-relativistic quantum chemical Hamiltonian
exploring the symmetric dissociation of the H$_{50}$ hydrogen chain.


title:
Determination of the stationary basis from protective measurement on a
  single system

abstract:
  We generalize protective measurement for protective joint measurement of
several observables. The merit of joint protective measurement is the
determination of the eigenstates of an unknown Hamiltonian rather than the
determination of features of an unknown quantum state. As an example, we
precisely determine the two eigenstates of an unknown Hamiltonian by a single
joint protective measurement of the three Pauli matrices on a qubit state.


title:
Minimal zero-sum sequences of length four over cyclic group with order
  $n=p^\alpha q^\beta$

abstract:
  Let $G$ be a finite cyclic group. Every sequence $S$ over $G$ can be written
in the form $S=(n_1g)\cdot...\cdot(n_kg)$ where $g\in G$ and
$n_1,\cdots,n_k\in[1,{\hbox{\rm ord}}(g)]$, and the index $\ind S$ of $S$ is
defined to be the minimum of $(n_1+\cdots+n_k)/\hbox{\rm ord}(g)$ over all
possible $g\in G$ such that $\langle g\rangle=G$. A conjecture says that if $G$
is finite such that $\gcd(|G|,6)=1$, then $\ind(S)=1$ for every minimal
zero-sum sequence $S$. In this paper, we prove that the conjecture holds if
$|G|$ has two prime factors.


title: Synchronizing Rankings via Interactive Communication

abstract:
  We consider the problem of exact synchronization of two rankings at remote
locations connected by a two-way channel. Such synchronization problems arise
when items in the data are distinguishable, as is the case for playlists,
tasklists, crowdvotes and recommender systems rankings. Our model accounts for
different constraints on the communication throughput of the forward and
feedback links, resulting in different anchoring, syndrome and checksum
computation strategies. Information editing is assumed of the form of
deletions, insertions, block deletions/insertions, translocations and
transpositions. The protocols developed under the given model are order-optimal
with respect to genie aided lower bounds.


title: Brooks' Vertex-Colouring Theorem in Linear Time

abstract:
  Brooks' Theorem [R. L. Brooks, On Colouring the Nodes of a Network, Proc.
Cambridge Philos. Soc.} 37:194-197, 1941] states that every graph $G$ with
maximum degree $\Delta$, has a vertex-colouring with $\Delta$ colours, unless
$G$ is a complete graph or an odd cycle, in which case $\Delta+1$ colours are
required. Lov\'asz [L. Lov\'asz, Three short proofs in graph theory, J. Combin.
Theory Ser. 19:269-271, 1975] gives an algorithmic proof of Brooks' Theorem.
Unfortunately this proof is missing important details and it is thus unclear
whether it leads to a linear time algorithm. In this paper we give a complete
description of the proof of Lov\'asz, and we derive a linear time algorithm for
determining the vertex-colouring guaranteed by Brooks' Theorem.


title: Louth Crater: Evolution of a layered water ice mound

abstract:
  We report on observations made of the ~36km diameter crater, Louth, in the
north polar region of Mars (at 70{\deg}N, 103.2{\deg}E). High-resolution
imagery from the instruments on the Mars Reconnaissance Orbiter (MRO)
spacecraft has been used to map a 15km diameter water ice deposit in the center
of the crater. The water ice mound has surface features that include roughened
ice textures and layering similar to that found in the North Polar Layered
Deposits. Features we interpret as sastrugi and sand dunes show consistent wind
patterns within Louth over recent time. CRISM spectra of the ice mound were
modeled to derive quantitative estimates of water ice and contaminant
abundance, and associated ice grain size information. These morphologic and
spectral results are used to propose a stratigraphy for this deposit and
adjoining sand dunes. Our results suggest the edge of the water ice mound is
currently in retreat.


title: Radio-continuum study of MCSNR J0536-7038 (DEM L249)

abstract:
  We present a detailed radio-continuum study on Australia Telescope Compact
Array (ATCA) observations of Large Magellanic Cloud (LMC) supernova remnant
(SNR), MCSNR J0536-7038. This Type Ia SNR follows a horseshoe morphology, with
a size 32 pc $\times$ 32 pc (1-pc uncertainty in each direction). It exhibits a
radio spectrum $\alpha=-0.52\pm0.07$ between $\lambda = 73$ and 6 cm. We report
detections of regions showing moderately high fractional polarisation at 6 cm,
with a peak value of 71$\pm$25% and a mean fractional polarisation of
35$\pm$8%. We also estimate an average rotation measure across the remnant of
-237 rad m$^{-2}$. The intrinsic magnetic field appears to be uniformly
distributed, extending in the direction of the two brightened limbs of the
remnant.


title:
Elimination of systemic risk in financial networks by means of a
  systemic risk transaction tax

abstract:
  Financial markets are exposed to systemic risk (SR), the risk that a major
fraction of the system ceases to function, and collapses. It has recently
become possible to quantify SR in terms of underlying financial networks where
nodes represent financial institutions, and links capture the size and maturity
of assets (loans), liabilities, and other obligations, such as derivatives. We
demonstrate that it is possible to quantify the share of SR that individual
liabilities within a financial network contribute to the overall SR. We use
empirical data of nationwide interbank liabilities to show that the marginal
contribution to overall SR of liabilities for a given size varies by a factor
of a thousand. We propose a tax on individual transactions that is proportional
to their marginal contribution to overall SR. If a transaction does not
increase SR it is tax-free. With an agent-based model (CRISIS macro-financial
model) we demonstrate that the proposed "Systemic Risk Tax" (SRT) leads to a
self-organised restructuring of financial networks that are practically free of
SR. The SRT can be seen as an insurance for the public against costs arising
from cascading failure. ABM predictions are shown to be in remarkable agreement
with the empirical data and can be used to understand the relation of credit
risk and SR.


title:
Vertex Operator Representations of Type $C_l^{(1)}$ and Product-Sum
  Identities

abstract:
  The purposes of this work are to construct a class of homogeneous vertex
representations of $C_l^{(1)} \ (l\geq2)$, and to derive a series of
product-sum identities. These identities have fine interpretation in number
theory.


title: Implicit dose-response curves

abstract:
  We develop tools from computational algebraic geometry for the study of
steady state features of autonomous polynomial dynamical systems via
elimination of variables. In particular, we obtain nontrivial bounds for the
steady state concentration of a given species in biochemical reaction networks
with mass-action kinetics. This species is understood as the output of the
network and we thus bound the maximal response of the system. The improved
bounds give smaller starting boxes to launch numerical methods. We apply our
results to the sequential enzymatic network studied in Markevich et al.(2004)
to find nontrivial upper bounds for the different substrate concentrations at
steady state.
  Our approach does not require any simulation, analytical expression to
describe the output in terms of the input, or the absence of multistationarity.
Instead, we show how to extract information from effectively computable
implicit dose-response curves with the use of resultants and discriminants. We
moreover illustrate in the application to an enzymatic network, the relation
between the exact implicit dose-response curve we obtain symbolically and the
standard hysteresis diagram provided by a numerical solver.
  The setting and tools we propose could yield many other results adapted to
any autonomous polynomial dynamical system, beyond those where it is possible
to get explicit expressions.


title:
Horn Coupled Multichroic Polarimeters for the Atacama Cosmology
  Telescope Polarization Experiment

abstract:
  Multichroic polarization sensitive detectors enable increased sensitivity and
spectral coverage for observations of the Cosmic Microwave Background (CMB). An
array optimized for dual frequency detectors can provide 1.7 times gain in
sensitivity compared to a single frequency array. We present the design and
measurements of horn coupled multichroic polarimeters encompassing the 90 and
150 GHz frequency bands and discuss our plans to field an array of these
detectors as part of the ACTPol project.


title:
Transit Fare Arbitrage: Case Study of San Francisco Bay Area Rapid
  Transit (BART) System

abstract:
  Transit fare arbitrage is the scenario when two or more commuters agree to
swap tickets during travel in such a way that total cost is lower than
otherwise. Such arbitrage allows pricing inefficiencies to be explored and
exploited, leading to improved pricing models. In this paper we discuss the
basics of fare arbitrage through an intuitive pricing framework involving
population density. We then analyze the San Francisco Bay Area Rapid Transit
(BART) system to understand underlying inefficiencies. We also provide source
code and comprehensive list of pairs of trips with significant arbitrage gain
at github.com/asifhaque/transit-arbitrage. Finally, we point towards a uniform
payment interface for different kinds of transit systems.


title: Two problems on coinvariant subspaces of the shift operator

abstract:
  Two problems are posed that involve the star-invariant subspace $K^p_\theta$
(in the Hardy space $H^p$) associated with an inner function $\theta$. One of
these asks for a characterization of the extreme points of the unit ball in
$K^\infty_\theta$, while the other concerns the Fermat equation $f^n+g^n=h^n$
in $K^p_\theta$.


title: Broadband chiral metamaterials with large optical activity

abstract:
  We study theoretically and experimentally a novel type of metamaterial with
hybrid elements composed of twisted pairs of cross-shaped meta-atoms and their
complements. We reveal that such two-layer metasurfaces demonstrate large,
dispersionless optical activity at the transmission resonance accompanied by
very low ellipticity. We develop a retrieval procedure to determine the
effective material parameters for this structure, which has lower-order
symmetry ($\mathrm {C}_4$) than other commonly studied chiral structures. We
verify our new theoretical approach by reproducing numerical and experimental
scattering parameters.


title:
Predicting magic numbers of nuclei with semi-realistic nucleon-nucleon
  interactions

abstract:
  Magic numbers are predicted in wide range of the nuclear chart by the
self-consistent mean-field calculations with the M3Y-P6 and P7 semi-realistic
$NN$ interactions. The magic numbers are identified by vanishing pair
correlations in the spherical Hartree-Fock-Bogolyubov regime. We also identify
submagic numbers when energy gain due to the pairing is sufficiently small. It
is found that the results with M3Y-P6 well correspond to the known data, apart
from a few exceptions. For some of the magic or submagic numbers the prediction
differs from that with the Gogny-D1S or D1M interaction. Roles of the tensor
force and the spin-isospin channel originating from the one-pion exchange
potential are investigated in the $Z$- or $N$-dependence of the shell gap.


title:
The effect of cell-attachment on the group of self-equivalences of an
  R-localized space

abstract:
  Let R be a subring of the rationals with least non-invertible prime p. Let X
= X^{n} \cup_{\alpha} (\bigcup_{j \in J} e^{q}) be a cell attachment with J
finite and q small with respect to p. Let E(X_R) denote the group of homotopy
self-equivalences of the R-localization X_R. We use DG Lie models to construct
a short exact sequence 0 \to \bigoplus_{j \in J}\pi_q(X^n)_R \to E(X_R) \to C^q
\to 0 where C^q is a subgroup of GL_{|J|}(R) \times E(X^n_R). We obtain a
related result for the R-localization of the nilpotent group E_*(X) of classes
inducing the identity on homology. We deduce some explicit calculations of both
groups for spaces with few cells.


title: Nano-pore based characterization of branched polymers

abstract:
  We propose a novel characterization method of randomly branched polymers
based on the geometrical property of such objects in confined spaces. The
central idea is that randomly branched polymers exhibit passing/clogging
transition across the nano-channel as a function of the channel size. This
critical channel size depends on the degree of the branching, whereby allowing
the extraction of the branching information of the molecule.


title: Sunquakes and starquakes

abstract:
  In addition to well-known mechanisms of excitation of solar and stellar
oscillations by turbulent convection and instabilities, the oscillations can be
excited by an impulsive localized force caused by the energy release in solar
and stellar flares. Such oscillations have been observed on the Sun
(`sunquakes'), and created a lot of interesting discussions about physical
mechanisms of the impulsive excitation and their relationship to the flare
physics. The observation and theory have shown that most of a sunquake's energy
is released in high-degree, high-frequency p modes. In addition, there have
been reports on helioseismic observations of low-degree modes excited by strong
solar flares. Much more powerful flares observed on other stars can cause
`starquakes' of substantially higher amplitude. Observations of such
oscillations can provide new asteroseismic information and also constraints on
mechanisms of stellar flares. The basic properties of sunquakes and initial
attempts to detect flare-excited oscillations in Kepler short-cadence data are
discussed.


title: Identities for generalized Euler polynomials

abstract:
  For $N \in \mathbb{N}$, let $T_{N}$ be the Chebyshev polynomial of the first
kind. Expressions for the sequence of numbers $p_{\ell}^{(N)}$, defined as the
coefficients in the expansion of $1/T_{N}(1/z)$, are provided. These
coefficients give formulas for the classical Euler polynomials in terms of the
so-called generalized Euler polynomials. The proofs are based on a
probabilistic interpretation of the generalized Euler polynomials recently
given by Klebanov et al. Asymptotics of $p_{\ell}^{(N)}$ are also provided.


title: Truthful Market-based Trading of Cloud Resources with Reservation Price

abstract:
  With the rapidly growing demand for the cloud services, a need for efficient
methods to trade computing resources increases. Commonly used fixed-price model
is not always the best approach for trading cloud resources, because of its
inflexible and static nature. Dynamic trading systems, which make use of market
mechanisms, show promise for more efficient resource allocation and pricing in
the cloud. However, most of the existing mechanisms ignore the seller's costs
of providing the resources. In order to address it, we propose a single-sided
market mechanism for trading virtual machine instances in the cloud, where the
cloud provider can express the reservation prices for traded cloud services. We
investigate the theoretical properties of the proposed mechanism and prove that
it is truthful, i.e. the buyers do not have an incentive to lie about their
true valuation of the resources. We perform extensive experiments in order to
investigate the impact of the reserve price on the market outcome. Our
experiments show that the proposed mechanism yields near optimal allocations
and has a low execution time.


title:
High-resolution kaonic-atom x-ray spectroscopy with
  transition-edge-sensor microcalorimeters

abstract:
  We are preparing for an ultra-high resolution x-ray spectroscopy of kaonic
atoms using an x-ray spectrometer based on an array of superconducting
transition-edge-sensor microcalorimeters developed by NIST. The instrument has
excellent energy resolutions of 2 - 3 eV (FWHM) at 6 keV and a large collecting
area of about 20 mm^2. This will open new door to investigate kaon-nucleus
strong interaction and provide new accurate charged-kaon mass value.


title: Free Energy Evaluation in Polymer Translocation via Jarzynski Equality

abstract:
  We perform, with the help of cloud computing resources, extensive Langevin
simulations which provide free energy estimates for unbiased three dimensional
polymer translocation. We employ the Jarzynski equality in its rigorous
setting, to compute the variation of the free energy in single monomer
translocation events. In our three-dimensional Langevin simulations, the
excluded-volume and van der Waals interactions between beads (monomers and
membrane atoms) are modeled through a repulsive Lennard-Jones (LJ) potential
and consecutive monomers are subject to the Finite-Extension Nonlinear Elastic
(FENE) potential. Analysing data for polymers with different lengths, the free
energy profile is noted to have interesting finite size scaling properties.


title: New Analysis of Threshold Photoproduction Data from MAMI

abstract:
  In this talk I will review the recently published results by the A2 and
CB-TAPS Collaborations at MAMI on neutral pion photoproduction in the
near-threshold region. The combined measurement of the differential cross
section and the photon beam asymmetry with low statistical errors allowed for a
precise determination of the energy dependence of the real parts of the S- and
P-wave amplitudes for the first time, providing the most stringent test to date
of the predictions of Chiral Perturbation Theory and its energy region of
agreement with experiment.


title: Online Dating Recommendations: Matching Markets and Learning Preferences

abstract:
  Recommendation systems for online dating have recently attracted much
attention from the research community. In this paper we proposed a two-side
matching framework for online dating recommendations and design an LDA model to
learn the user preferences from the observed user messaging behavior and user
profile features. Experimental results using data from a large online dating
website shows that two-sided matching improves significantly the rate of
successful matches by as much as 45%. Finally, using simulated matchings we
show that the the LDA model can correctly capture user preferences.


title: Absence of zero resonances of massless Dirac operators

abstract:
  We consider the massless Dirac operator $H=\alpha \cdot D+Q(x)$ on the
Hilbert space $L^{2}(\mathbb{R}^{3},\mathbb{C}^{4})$, where $Q(x)$ is a
$4\times4$ Hermitian matrix valued function which suitably decays at infinity.
We show that the the zero resonance is absent for $H$, extending recent results
of Sait\={o}-Umeda and Zhong-Gao.


title:
Preserving Lagrangian structure in nonlinear model reduction with
  application to structural dynamics

abstract:
  This work proposes a model-reduction methodology that preserves Lagrangian
structure (equivalently Hamiltonian structure) and achieves computational
efficiency in the presence of high-order nonlinearities and arbitrary parameter
dependence. As such, the resulting reduced-order model retains key properties
such as energy conservation and symplectic time-evolution maps. We focus on
parameterized simple mechanical systems subjected to Rayleigh damping and
external forces, and consider an application to nonlinear structural dynamics.
To preserve structure, the method first approximates the system's `Lagrangian
ingredients'---the Riemannian metric, the potential-energy function, the
dissipation function, and the external force---and subsequently derives
reduced-order equations of motion by applying the (forced) Euler--Lagrange
equation with these quantities. From the algebraic perspective, key
contributions include two efficient techniques for approximating parameterized
reduced matrices while preserving symmetry and positive definiteness: matrix
gappy POD and reduced-basis sparsification (RBS). Results for a parameterized
truss-structure problem demonstrate the importance of preserving Lagrangian
structure and illustrate the proposed method's merits: it reduces computation
time while maintaining high accuracy and stability, in contrast to existing
nonlinear model-reduction techniques that do not preserve structure.


title: A Supersolid Skin Covering both Water and Ice

abstract:
  The mysterious nature and functionality of water and ice skins remain
baffling to the community since 1859 when Farady firstly proposed liquid skin
lubricating ice. Here we show the presence of supersolid phase that covers both
water and ice using Raman spectroscopy measurements and quantum calculations.
In the skin of two molecular layers thick, molecular undercoordination shortens
the H-O bond by ~16% and lengthens the OH nonbond by ~25% through repulsion
between electron pairs on adjacent O atoms, which depresses the density from
0.92 for bulk ice to 0.75 gcm-3. The O:H-O cooperative relaxation stiffens the
H-O stretching phonon from 3200/3150 cm-1 to the same value of 3450 cm-1 and
raises the melting temperature of both skins by up to ~310 K. Numerical
derivatives on the viscosity and charge accumulation suggests that the elastic,
polarized, and thermally stable supersolid phase makes the ice frictionless and
water skin hydrophobic and ice like at room temperature.


title: Universal First-Order Logic is Superfluous for NL, P, NP and coNP

abstract:
  In this work we continue the syntactic study of completeness that began with
the works of Immerman and Medina. In particular, we take a conjecture raised by
Medina in his dissertation that says if a conjunction of a second-order and a
first-order sentences defines an NP-complete problems via fops, then it must be
the case that the second-order conjoint alone also defines a NP-complete
problem. Although this claim looks very plausible and intuitive, currently we
cannot provide a definite answer for it. However, we can solve in the
affirmative a weaker claim that says that all ``consistent'' universal
first-order sentences can be safely eliminated without the fear of losing
completeness. Our methods are quite general and can be applied to complexity
classes other than NP (in this paper: to NLSPACE, PTIME, and coNP), provided
the class has a complete problem satisfying a certain combinatorial property.


title:
Regularity of Solutions to Degenerate Non-Doubling Second Order
  Equations

abstract:
  We prove that every weak solution to a certain class of infinitely degenerate
quasilinear equations is continuous. An essential feature of the operators we
consider is that their Fefferman-Phong associated metric may be non doubling
with respect to Lebesgue measure.


title: A Note On Einstein, Bergmann, and the Fifth Dimension

abstract:
  This note is devoted to a detail concerning the work of Albert Einstein and
Peter Bergmann on unified theories of electromagnetism and gravitation in five
dimensions. In their paper of 1938, Einstein and Bergmann were among the first
to introduce the modern viewpoint in which a four-dimensional theory that
coincides with Einstein-Maxwell theory at long distances is derived from a
five-dimensional theory with complete symmetry among all five dimensions. But
then they drew back, modifying the theory in a way that spoiled the
five-dimensional symmetry and looks contrived to modern readers. Why? According
to correspondence of Peter Bergmann with the author, the reason was that the
more symmetric version of the theory predicts the existence of a new long range
field (a massless scalar field). In 1938, Einstein and Bergmann did not wish to
make this prediction. (Based on a lecture at the Einstein Centennial
Celebration at the Library of Alexandria, June, 2005.


title:
The Galerkin Finite Element Method for A Multi-term Time-Fractional
  Diffusion equation

abstract:
  We consider the initial/boundary value problem for a diffusion equation
involving multiple time-fractional derivatives on a bounded convex polyhedral
domain. We analyze a space semidiscrete scheme based on the standard Galerkin
finite element method using continuous piecewise linear functions. Nearly
optimal error estimates for both cases of initial data and inhomogeneous term
are derived, which cover both smooth and nonsmooth data. Further we develop a
fully discrete scheme based on a finite difference discretization of the
time-fractional derivatives, and discuss its stability and error estimate.
Extensive numerical experiments for one and two-dimension problems confirm the
convergence rates of the theoretical results.


title: Birational Geometry of the Space of Complete Quadrics

abstract:
  We study the birational geometry of the moduli space of complete $n$-quadrics
$X$. We exhibit generators for Eff$(X)$ and Nef$(X)$, the cone of effective
divisors and the cone of nef divisors, respectively. As a corollary X is a Mori
Dream space. Furthermore, we run the MMP on $X$ and find a moduli
interpretation for the models induced by the generators of the nef cone. In the
case of complete quadric surfaces, we describe all the birational models of $X$
induced by the movable cone and find a moduli interpretation for some of these
models.


title: Thermodynamical properties of graphene in noncommutative phase-space

abstract:
  We investigated the thermodynamic properties of graphene in a noncommutative
phase-space in the presence of a constant magnetic field. In particular, we
determined the behaviour of the main thermodynamical functions: the Helmholtz
free energy, the mean energy, the entropy and the specific heat. The high
temperature limit is worked out and the thermodynamic quantities, such as mean
energy and specific heat, exhibit the same features as the commutative case.
Possible connections with the results already established in the literature are
discussed briefly.


title: On generating functions of Hausdorff moment sequences

abstract:
  The class of generating functions for completely monotone sequences (moments
of finite positive measures on $[0,1]$) has an elegant characterization as the
class of Pick functions analytic and positive on $(-\infty,1)$. We establish
this and another such characterization and develop a variety of consequences.
In particular, we characterize generating functions for moments of convex and
concave probability distribution functions on $[0,1]$. Also we provide a simple
analytic proof that for any real $p$ and $r$ with $p>0$, the Fuss-Catalan or
Raney numbers $\frac{r}{pn+r}\binom{pn+r}{n}$, $n=0,1,\ldots$ are the moments
of a probability distribution on some interval $[0,\tau]$ {if and only if}
$p\ge1$ and $p\ge r\ge 0$. The same statement holds for the binomial
coefficients $\binom{pn+r-1}n$, $n=0,1,\ldots$.


title: Hallucinating optimal high-dimensional subspaces

abstract:
  Linear subspace representations of appearance variation are pervasive in
computer vision. This paper addresses the problem of robustly matching such
subspaces (computing the similarity between them) when they are used to
describe the scope of variations within sets of images of different (possibly
greatly so) scales. A naive solution of projecting the low-scale subspace into
the high-scale image space is described first and subsequently shown to be
inadequate, especially at large scale discrepancies. A successful approach is
proposed instead. It consists of (i) an interpolated projection of the
low-scale subspace into the high-scale space, which is followed by (ii) a
rotation of this initial estimate within the bounds of the imposed
``downsampling constraint''. The optimal rotation is found in the closed-form
which best aligns the high-scale reconstruction of the low-scale subspace with
the reference it is compared to. The method is evaluated on the problem of
matching sets of (i) face appearances under varying illumination and (ii)
object appearances under varying viewpoint, using two large data sets. In
comparison to the naive matching, the proposed algorithm is shown to greatly
increase the separation of between-class and within-class similarities, as well
as produce far more meaningful modes of common appearance on which the match
score is based.


title:
Radial Deformations and Cavitation in Riemannian Manifolds with
  Applications to Membrane Shells

abstract:
  This study is a geometric version of Ball's work, Philos. Trans. Roy. Soc.
London Ser. A 306 (1982), no. 1496, 557-611. Radial deformations in Riemannian
manifolds are singular solutions to some nonlinear equations given by
constitutive functions and radial curvatures. A geodesic spherical cavity forms
at the center of a geodesic ball in tension by means of given surface tractions
or displacements. The existence of such solutions depends on the growth
properties of the constitutive functions and the radial curvatures.
  Some close relationships are shown among radial curvature, the constitutive
functions, and the behavior of bifurcation of a singular solution from a
trivial solution. In the incompressible case the bifurcation depends on the
local properties of the radial curvature near the geodesic ball center but the
bifurcation in compressible case is determined by the global properties of the
radial curvatures.
  A cavity forms at the center of a membrane shell of isotropic material placed
in tension by means of given boundary tractions or displacements when the
Riemannian manifold under question is a surface of $\R^3$ with the induced
metric. In addition, cavitation at the center of ellipsoids of $\R^n$ is also
described if the Riemannian manifold under question is $(\R^n g)$ where $g(x)$
are symmetric, positive matrices for $x\in\R^n.$


title: On the active manipulation of EM fields in open waveguides

abstract:
  In this paper we present the extension of the results proposed in
\cite{Onofrei-S} and study the problem of active control of TM waves
propagating in a waveguide. The main goal is to cancel, in a prescribed near
field region, the longitudinal component of the electric field of an incoming
TM wave while having vanishingly small fields near the waveguide boundary. The
main analytical challenge is to design appropriate source functions for the
scalar Helmholtz equation so that the desired cancellation effect will be
obtained. We show the existence of a class of solutions to the problem and
provide numerical support of the results. Discussion on the feasibility of the
proposed approach as well as possible design strategies are offered.


title: Towards a quantitative kinetic theory of polar active matter

abstract:
  A recent kinetic approach for Vicsek-like models of active particles is
reviewed. The theory is based on an exact Chapman-Kolmogorov equation in phase
space. It can handle discrete time dynamics and "exotic" multi-particle
interactions. A nonlocal mean-field theory for the one-particle distribution
function is obtained by assuming molecular chaos. The Boltzmann approach of
Bertin et al., Phys. Rev. E 74, 022101 (2006) and J. Phys. A: Math. Theor. 42,
445001 (2009), is critically assessed and compared to the current approach. In
Boltzmann theory, a collision starts when two particles enter each others
action spheres and is finished when their distance exceeds the interaction
radius. The average duration of such a collision, $\tau_0$, is measured for the
Vicsek model with continuous time-evolution. If the noise is chosen to be close
to the flocking threshold, the average time between collisions is found to be
roughly equal to $\tau_0$ at low densities. Thus, the continuous-time
Vicsek-model near the flocking threshold cannot be accurately described by a
Boltzmann equation, even at very small density because collisions take so long
that typically other particles join in, rendering Boltzmann's binary collision
assumption invalid. Hydrodynamic equations for the phase space approach are
derived by means of a Chapman-Enskog expansion. The equations are compared to
the Toner-Tu theory of polar active matter. New terms, absent in the Toner-Tu
theory, are highlighted. Convergence problems of Chapman-Enskog and similar
gradient expansions are discussed.


title: On the homology of Iwasawa cohomology groups

abstract:
  A fundamental observation of Iwasawa gives a criterion for a module over the
classical Iwasawa algebra to be torsion. In this paper, we study a certain
extension of this criterion. We will then apply this to study the structure of
the homology of the "Iwasawa cohomology groups" and dual fine Selmer groups.


title:
On the Study of the General Group Classification of Systems of Linear
  Second-Order Ordinary Differential Equations

abstract:
  In this paper we study the general group classification of systems of linear
second-order ordinary differential equations inspired from earlier works and
recent results on the group classification of such systems. Some interesting
results and subsequent Theorem arising from this particular study are discussed
here. This paper considers the study of irreducible systems of second-order
ordinary differential equations.


title: Multiscale polar theory of microtubule and motor-protein assemblies

abstract:
  Microtubules and motor proteins are building blocks of self-organized
subcellular biological structures such as the mitotic spindle and the
centrosomal microtubule array. These same ingredients can form new "bioactive"
liquid-crystalline fluids that are intrinsically out of equilibrium and which
display complex flows and defect dynamics. It is not yet well understood how
microscopic activity, which involves polarity-dependent interactions between
motor proteins and microtubules, yields such larger scale dynamical structures.
In our multiscale theory, Brownian dynamics simulations of polar microtubule
ensembles driven by crosslinking motors allow us to study microscopic
organization and stresses. Polarity sorting and crosslink relaxation emerge as
two polar-specific sources of active destabilizing stress. On larger length
scales, our continuum Doi-Onsager theory captures the hydrodynamic flows
generated by polarity-dependent active stresses. The results connect local
polar structure to flow structures and defect dynamics.


title:
Seedless clustering in all-sky searches for gravitational-wave
  transients

abstract:
  The problem of searching for unmodeled gravitational-wave bursts can be
thought of as a pattern recognition problem: how to find statistically
significant clusters in spectrograms of strain power when the precise signal
morphology is unknown. In a previous publication, we showed how "seedless
clustering" can be used to dramatically improve the sensitivity of searches for
long-lived gravitational-wave transients. In order to manage the computational
costs, this initial analysis focused on externally triggered searches where the
source location and emission time are both known to some degree of precision.
In this paper, we show how the principle of seedless clustering can be extended
to facilitate computationally-feasible, all-sky searches where the direction
and emission time of the source are entirely unknown. We further demonstrate
that it is possible to achieve a considerable reduction in computation time by
using graphical processor units (GPUs), thereby facilitating more sensitive
searches.


title: Coverings of graded pointed Hopf algebras

abstract:
  We introduce the concept of a covering of a graded pointed Hopf algebra. The
theory developed shows that coverings of a bosonized Nichols algebra can be
concretely expressed by biproducts using a quotient of the universal coalgebra
covering group of the Nichols algebra. If there are enough quadratic relations,
the universal coalgebra covering is given by the bosonization by the enveloping
group of the underlying rack.