title:
Substance Abuse via Legally Prescribed Drugs: The Case of Vicodin in the
  United States

abstract:
  Vicodin is the most commonly prescribed pain reliever in the United States.
Research indicates that there are two million people who are currently abusing
Vicodin, and the majority of those who abuse Vicodin were initially exposed to
it via prescription. Our goal is to determine the most effective strategies for
reducing the overall population of Vicodin abusers. More specifically, we focus
on whether prevention methods aimed at educating doctors and patients on the
potential for drug abuse or treatment methods implemented after a person abuses
Vicodin will have a greater overall impact. We consider one linear and two
non-linear compartmental models in which medical users of Vicodin can
transition into the abuser compartment or leave the population by no longer
taking the drug. Once Vicodin abusers, people can transition into a treatment
compartment, with the possibility of leaving the population through successful
completion of treatment or of relapsing and re-entering the abusive
compartment. The linear model assumes no social interaction, while both
non-linear models consider interaction. One considers interaction with abusers
affecting the relapse rate, while the other assumes both this and an additional
interaction between the number of abusers and the number of new prescriptions.
Sensitivity analyses are conducted varying the rates of success of these
intervention methods measured by the parameters to determine which strategy has
the greatest impact on controlling the population of Vicodin abusers. From
these models and analyses, we determine that manipulating parameters tied to
prevention measures has a greater impact on reducing the population of abusers
than manipulating parameters associated with treatment. We also note that
increasing the rate at which abusers seek treatment affects the population of
abusers more than the success rate of treatment itself.


title:
Black hole triple dynamics: breakdown of the orbit average approximation
  and implications for gravitational wave detections

abstract:
  Coalescing black hole (BH) binaries forming in the dense core of globular
clusters (GCs) are expected to be one the brightest sources of gravitational
wave (GW) radiation for the next generation of ground-based laser
interferometers. Favorable conditions for merger are initiated by the Kozai
resonance in which the gravitational interaction with a third distant object,
typically another BH, induces quasi-periodic variations of the inner BH binary
eccentricity. In this paper we perform high precision N-body simulations of the
long term evolution of hierarchical BH triples and investigate the conditions
that lead to the merging of the BH binary and the way it might become an
observable source of GW radiation. We find that the secular orbit average
treatment, adopted in previous works, does not reliably describe the dynamics
of these systems if the binary is orbited by the outer BH on a highly inclined
orbit at a moderate distance. During the high eccentricity phase of a Kozai
cycle the torque due to the outer BH can drive the binary to extremely large
eccentricities in a fraction of the binary's orbital period. This occurs before
relativistic terms become important to the evolution and allows the binary GW
signal to reach large GW frequencies (>~10 Hz) at high eccentricities. We show
that ~50 % of coalescing BH binaries driven by the Kozai mechanism in GCs will
have eccentricities larger than 0.1, with 10 % of them being extremely
eccentric, (1-e)<~10^-5, when they first chirp in the frequency band of ground
based laser interferometers. This implies that a large fraction of such GW
sources could be missed if conventional quasi-circular templates are used for
analysis of GW detectors data. The efficient detection of all coalescing BH
binaries in GCs will therefore require template banks of eccentric inspiral
waveforms for matched-filtering and dedicated search strategies.


title:
Dynamics and Control of an Invasive Species: The Case of the Rasberry
  Crazy Ant Colonies

abstract:
  This project is motivated by the costs related with the documented risks of
the introduction of non-native invasive species of plants, animals, or
pathogens associated with travel and international trade. Such invasive species
often have no natural enemies in their new regions. The spatiotemporal dynamics
related to the invasion/spread of Nylanderia fulva, commonly known as the
Rasberry crazy ant, are explored via the use of models that focus on the
reproduction of ant colonies. A Cellular Automaton (CA) simulates the spatially
explicit spread of ants on a grid. The impact of local spatial correlations on
the dynamics of invasion is investigated numerically and analytically with the
aid of a Mean Field (MF) model and a Pair Approximation (PA) model, the latter
of which accounts for adjacent cell level efects. The PA model approach
considers the limited mobility range of N. fulva, that is, the grid cell
dynamics are not strongly in uenced by non-adjacent cells. The model determines
the rate of growth of colonies of N. fulva under distinct cell spatial
architecture. Numerical results and qualitative conclusions on the spread and
control of this invasive ant species are discussed.


title:
Thermodynamic anomalies and structural fluctuations in aqueous solutions
  of tertiary butyl alcohol

abstract:
  In this work, we discuss the connection between the anomalies of the
thermodynamic properties, experimentally observed in tertiary butyl alcohol
(TBA) and water solutions, and the molecular clustering in these solutions, as
revealed by molecular dynamics (MD) simulations. These anomalies are observed
in relatively dilute solutions of about 0.03 to 0.08 mole fraction of TBA and
become more pronounced at low temperatures. MD simulations show that these
solutions exhibit shortranged (order of 1 nm), shortlived (tens of picoseconds)
"micelle-like" structural fluctuations in the same concentration range. We
attribute the anomalies in the thermodynamic properties of aqueous TBA
solutions to these structural fluctuations on the molecular scale.


title: Neutron-hole states in 45Ar from p(46Ar,d)45Ar reactions

abstract:
  To improve the effective interactions in the pf shell, it is important to
measure the single particle- and hole- states near the N=28 shell gap. In this
paper, the neutron spectroscopic factors of hole-states from the unstable
neutron-rich 45Ar (Z=18, N=27) nucleus have been studied using 1H(46Ar, 2H)45Ar
transfer reaction in inverse kinematics. Comparison of our results with the
particle-states of 45Ar produced in 2H(44Ar, H)45Ar reaction shows that the two
reactions populate states with different angular momentum. Using the angular
distributions, we are able to confirm the spin assignments of four low-lying
states of 45Ar. These are the ground state (f7/2), the first-excited (p3/2),
the s1/2 and the d3/2 states. While large basis shell model predictions
describe spectroscopic properties of the ground and p3/2 states very well, they
fail to describe the s1/2 and d3/2 hole-states.


title: Preventing Exceptions to Robins InEquality

abstract:
  For sufficiently large n Ramanujan gave a sufficient condition for the truth
Robin's InEquality $X(n):=\frac{\sigma(n)}{n\ln\ln n}<e^{\gamma}$ (RIE). The
largest known violation of RIE is $n_8=5040$. In this paper Robin's multipliers
are split into logarithmic terms $\mathcal{L}$ and relative divisor sums
$\mathcal{G}$. A violation of RIE above $n_{8}$ is proposed to imply
oscillations that cause $\mathcal{G}$ to exceed $\mathcal{L}$. To this aim
Alaoglu and Erd\H{o}s's conjecture for the CA numbers algorithm is used and the
paper's key points are in section 4.2


title: Just In Time Indexing

abstract:
  One of the major challenges being faced by Database managers today is to
manage the performance of complex SQL queries which are dynamic in nature.
Since it is not possible to tune each and every query because of its dynamic
nature, there is a definite possibility that these queries may cause serious
database performance issues if left alone. Conventional indexes are useful only
for those queries which are frequently executed or those columns which are
frequently joined in SQL queries. This proposal is regarding a method, a query
optimizer for optimizing database queries in a database management system. Just
In Time(JIT) indexes are On Demand, temporary indexes created on the fly based
on current needs so that they would be able to satisfy any kind of queries. JIT
indexes are created only when the configured threshold values for resource
consumption are exceeded for a query. JIT indexes will be stored in a temporary
basis and will get replaced by new JIT indexes in course of time. The proposal
is substantiated with the help of experimental programs and with various test
cases. The idea of parallel programming is also brought into picture as it can
be effectively used in a multiprocessor system. Multiple threads are employed
while one set of threads proceed in the conventional way and the other set of
threads proceed with the proposed way. A live switch over is made when a
suitable stage is reached and from then onwards the proposed method will only
come into picture.


title: Tilted Lema\^itre model and the dark flow

abstract:
  In the last years, the peculiar velocities of many X-ray galaxies clusters
with respect to the distance have been measured directly in the rest frame of
the cosmic microwave background radiation (CBR), using the kinematic
Sunyaev-Zeldovich (kSZ) effect. These measures prove that exists a highly
coherent motion, extending out to at least to ~1 Gpc, of the matter rest frame
with respect to the CBR rest frame. This global motion was named "dark flow".
By using an inhomogeneous spherically symmetric "tilted" Lema\^itre model, we
could explain the dark flow if we assume a linear increase with distance of the
peculiar velocities, which is in principle allowed by these observations. This
linear increase of the dark flow with the distance has the same behavior that
the intrinsic dipole, due to the kinematic acceleration, which appears in the
Hubble law of the Lema\^itre model. In the "tilted" Lema\^itre model
considered, we consider that the radiation orthogonal congruence is a perfect
fluid and the matter "tilted" congruence is an imperfect fluid with heat flux.


title:
Prediction Capabilities of VLF/LF Emission as the Main Precursor of
  Earthquake

abstract:
  Recent satellite and ground-based observations proved that in earthquake
preparation period in the seismogenic area we have VLF/LF and ULF
electromagnetic emissions. According to the opinion of the authors of the
present paper this phenomenon is more universal and reliable than other
earthquake indicators. Hypothetically, in case of availability of adequate
methodological grounds, in the nearest future, earth VLF/LF electromagnetic
emission might be declared as the main precursor of earthquake. In particular,
permanent monitoring of frequency spectrum of earth electromagnetic emission
generated in the earthquake preparation period might turn out very useful with
the view of prediction of large (M 5) inland earthquakes. The present paper
offers a scheme of the methodology according to which the reality of the above
given hypothesis can be checked up. To prove the prediction capabilities of
earth electromagnetic emission we have used avalanche-like unstable model of
fault formation and an analogous model of electromagnetic contour, synthesis of
which, according to our opinion, is rather harmonious.


title:
A Closer Look at the Fluctuations in Brightness of SN 2009ip During Its
  Late 2012 Eruption

abstract:
  The supernova impostor SN 2009ip has re-brightened several times since its
initial discovery in August 2009. During its last outburst in late September
2012 it reached a peak brightness of m$_v$ $\sim$ 13.5 (M$_v$ brighter than
-18) causing some to speculate that it had undergone a terminal core-collapse
supernova. Relatively high-cadence multi-wavelength photometry of the post-peak
decline revealed bumps in brightness infrequently observed in other Type IIn
supernovae. These bumps occurred synchronously in all UV and optical bands with
amplitudes of 0.1 -- 0.4 mag at intervals of 10 -- 30 days. Episodic continuum
brightening and dimming in the UV and optical with these characteristics is not
easilly explained within the context of models that have been proposed for the
late September 2012 outburst of SN 2009ip. We also present evidence that the
post peak fluctuations in brightness occur at regular intervals and raise more
questions about their origin.


title: Non-Zeeman Circular Polarization of CO rotational lines in SNR IC 443

abstract:
  Context: We investigate non-Zeeman circular polarization and linear
polarization levels of up to 1% of $^{12}$CO spectral line emission detected in
a shocked molecular clump around the supernova remnant (SNR) IC 443, with the
goal of understanding the magnetic field structure in this source. Aims: We
examine our polarization results to confirm that the circular polarization
signal in CO lines is caused by a conversion of linear to circular
polarization, consistent with anisotropic resonant scattering. In this process
background linearly polarized CO emission interacts with similar foreground
molecules aligned with the ambient magnetic field and scatters at a transition
frequency. The difference in phase shift between the orthogonally polarized
components of this scattered emission can cause a transformation of linear to
circular polarization. Methods: We compared linear polarization maps from dust
continuum, obtained with PolKa at APEX, and $^{12}$CO ($J=2\rightarrow1$) and
($J=1\rightarrow0$) from the IRAM 30-m telescope and found no consistency
between the two sets of polarization maps. We then reinserted the measured
circular polarization signal in the CO lines across the source to the
corresponding linear polarization signal to test whether before this linear to
circular polarization conversion the linear polarization vectors of the CO maps
were aligned with those of the dust. Results: After the flux correction for the
two transitions of the CO spectral lines, the new polarization vectors for both
CO transitions aligned with the dust polarization vectors, establishing that
the non-Zeeman CO circular polarization is due to a linear to circular
polarization conversion.


title:
Dielectric relaxation of water below the melting point: the effect of
  inner pressure

abstract:
  Despite water is the most studied substance in the Earth, it is not
completely understood why its structural and dynamical properties give rise to
some anomalous behaviors. Interesting properties emerge when experiments at low
temperatures and/or high pressures, are performed. Here we report dielectric
measurements of cold water under constrained conditions, i.e. water that below
the melting point can not freeze. The inner pressure shifts the {\alpha}
relaxation peak to similar frequencies as seen in ice Ih. Also, when we reach
the triple point at 251 K, ice III seems to form. As far as we know, this via
to obtain such crystalline phase has not been observed.


title:
The effect of magnetic fields on the r-modes of slowly rotating
  relativistic neutron stars

abstract:
  We study here the r-modes in the Cowling approximation of a slowly rotating
and magnetized neutron star with a poloidal magnetic field, where we neglect
any deformations of the spherical symmetry of the star. We were able to
quantify the influence of the magnetic field in both the oscillation frequency
$\sigma_r$ of the r-modes and the growth time $t_{gw}$ of the gravitational
radiation emission. We conclude that magnetic fields of the order $10^{15}$ G
at the center of the star are necessary to produce any changes. Our results for
$\sigma_r$ show a decrease of up to $\sim$ $5\%$ in the frequency with
increasing magnetic field, with a $B^2$ dependence for rotation rates
$\Omega/\Omega_K \gtrsim 0.07$ and $B^4$ for $\Omega/\Omega_K \lesssim 0.07$.
(These results should be trusted only within slow rotation approximation and we
kept $\Omega/\Omega_{K}< 0.3$.) For $t_{gw}$, we find that it is approximately
$30\%$ smaller than previous Newtonian results for non-magnetized stars, which
would mean a faster growth of the emission of gravitational radiation. The
effect of the magnetic field in $t_{gw}$ causes a non-monotonic effect, that
first slightly increases $t_{gw}$ and then decreases it further by another
$\sim$ $5\%$. (The value of magnetic field for which $t_{gw}$ starts to
decrease depends on the rotational frequency, but it is generally around
$10^{15}$G.) Future work should be dedicated to the study of the effect of
viscosity in the presence of magnetic fields, in order to establish the
magnetic correction to the instability window.


title: A new filtration of the Magnus kernel of the Torelli group

abstract:
  For a oriented genus g surface with one boundary component, S, the Torelli
group is the group of orientation preserving homeomorphisms of S that induce
the identity on homology. The Magnus representation of the Torelli group
represents the action on F/F" where F=pi_1(S) and F" is the second term of the
derived series. We show that the kernel of the Magnus representation, Mag(S),
is highly non-trivial and has a rich structure as a group. Specifically, we
define an infinite filtration of Mag(S) by subgroups, called the higher order
Magnus subgroups, M_k(S). We develop methods for generating nontrivial mapping
classes in M_k(S) for all k and g>1. We show that for each k the quotient
M_k(S)/M_{k+1}(S) contains a subgroup isomorphic to a lower central series
quotient of free groups E(g-1)_k/E(g-1)_{k+1}. Finally We show that for g>2 the
quotient M_k(S)/M_{k+1}(S) surjects onto an infinite rank torsion free abelian
group. To do this, we define a Johnson-type homomorphism on each higher order
Magnus subgroup quotient and show it has a highly non-trivial image.


title:
A semiclassical collective response of heated, asymmetric and rotating
  nuclei

abstract:
  The Landau Fermi-liquid and extended Gutzwiller periodic-orbit theories are
presented for the semiclassical description of collective excitations in
nuclei, which are close to main topics of the fruitful activity of S.T.
Belyaev. Static susceptibilities show the ergodicity of Fermi liquids.
Transport coefficients (nuclear friction and inertia) as functions of the
temperature for the hydrodynamic and zero-sound modes are derived within the
response theory by using the Fermi-liquid droplet model, in agreement with the
shell model for large temperatures. The surface symmetry binding-energy
constants are obtained as functions of Skyrme force parameters in the
approximation of a sharp edged proton-neutron asymmetric nucleus.The energies
and sum rules of the isovector dipole giant resonances are in fairly good
agreement with the experimental data. An analysis of the specific structure of
these resonances in terms of a main, and satellite peaks, in comparison with
the experimental data and microscopic theoretical models, might turn out to be
of importance for a better understanding of the values of the surface
symmetry-energy constant. The semiclassical collective moment of inertia is
derived analytically beyond the quantum perturbation approximation of the
cranking model for any potential well as a mean field. It is shown that this
moment of inertia can be approximated by its rigid-body value for the rotation
with a given frequency within the ETF and more general periodic orbit theories
in the nearly local long-length approximation. Its semiclassical
shell-structure components are derived in terms of the periodic-orbit
free-energy shell corrections. We obtained good agreement between the
semiclassical and quantum shell-structure components of the moment of inertia
for several critical bifurcation deformations for the harmonic oscillator mean
field.


title: Stable reflexive sheaves and localization

abstract:
  We study moduli spaces $\mathcal{N}$ of rank 2 stable reflexive sheaves on
$\mathbb{P}^3$. Fixing Chern classes $c_1$, $c_2$, and summing over $c_3$, we
consider the generating function $\mathsf{Z}^{\mathrm{refl}}(q)$ of Euler
characteristics of such moduli spaces. The action of the torus $T$ on
$\mathbb{P}^3$ lifts to $\mathcal{N}$ and we classify all sheaves in
$\mathcal{N}^T$. This leads to an explicit expression for
$\mathsf{Z}^{\mathrm{refl}}(q)$. Since $c_3$ is bounded below and above,
$\mathsf{Z}^{\mathrm{refl}}(q)$ is a polynomial. We find a simple formula for
its leading term when $c_1=-1$.
  Next, we study moduli spaces of rank 2 stable torsion free sheaves on
$\mathbb{P}^3$ and consider the generating function of Euler characteristics of
such moduli spaces. We give an expression for this generating function in terms
of $\mathsf{Z}^{\mathrm{refl}}(q)$ and Euler characteristics of Quot schemes of
certain $T$-equivariant reflexive sheaves, which are studied elsewhere. Many
techniques of this paper apply to any toric 3-fold. In general,
$\mathsf{Z}^{\mathrm{refl}}(q)$ depends on the choice of polarization which
leads to wall-crossing phenomena. We briefly illustrate this in the case of
$\mathbb{P}^2 \times \mathbb{P}^1$.


title: Evolving a Behavioral Repertoire for a Walking Robot

abstract:
  Numerous algorithms have been proposed to allow legged robots to learn to
walk. However, the vast majority of these algorithms is devised to learn to
walk in a straight line, which is not sufficient to accomplish any real-world
mission. Here we introduce the Transferability-based Behavioral Repertoire
Evolution algorithm (TBR-Evolution), a novel evolutionary algorithm that
simultaneously discovers several hundreds of simple walking controllers, one
for each possible direction. By taking advantage of solutions that are usually
discarded by evolutionary processes, TBR-Evolution is substantially faster than
independently evolving each controller. Our technique relies on two methods:
(1) novelty search with local competition, which searches for both
high-performing and diverse solutions, and (2) the transferability approach,
which com-bines simulations and real tests to evolve controllers for a physical
robot. We evaluate this new technique on a hexapod robot. Results show that
with only a few dozen short experiments performed on the robot, the algorithm
learns a repertoire of con-trollers that allows the robot to reach every point
in its reachable space. Overall, TBR-Evolution opens a new kind of learning
algorithm that simultaneously optimizes all the achievable behaviors of a
robot.


title:
Reduction of breast cancer relapses with perioperative non-steroidal
  anti-inflammatory drugs: new findings and a review

abstract:
  To explain a bimodal pattern of hazard of relapse among early stage breast
cancer patients identified in multiple databases, we proposed that late
relapses result from steady stochastic progressions from single dormant
malignant cells to avascular micrometastases and then on to growing deposits.
However in order to explain early relapses, we had to postulate that something
happens at about the time of surgery to provoke sudden exits from dormant
phases to active growth and then to detection. Most relapses in breast cancer
are in the early category. Recent data from Forget et al suggests an unexpected
mechanism. They retrospectively studied results from 327 consecutive breast
cancer patients comparing various perioperative analgesics and anesthetics in
one Belgian hospital and one surgeon. Patients were treated with mastectomy and
conventional adjuvant therapy. Relapse hazard updated Sept 2011 are presented.
A common Non-Steroidal Anti-Inflammatory Drug (NSAID) analgesic used in surgery
produced far superior disease-free survival in the first 5 years after surgery.
The expected prominent early relapse events in months 9-18 are reduced 5-fold.
If this observation holds up to further scrutiny, it could mean that the simple
use of this safe, inexpensive and effective anti-inflammatory agent at surgery
might eliminate early relapses. Transient systemic inflammation accompanying
surgery could facilitate angiogenesis of dormant micrometastases, proliferation
of dormant single cells, and seeding of circulating cancer stem cells (perhaps
in part released from bone marrow) resulting in early relapse and could have
been effectively blocked by the perioperative anti-inflammatory agent.


title:
Surprisingly Long Length Scales for Semiclassical Loop Quantum Gravity
  and Their Physical Consequences

abstract:
  When gauge field theory coherent states for loop quantum gravity (LQG) were
introduced, an optimized semiclassical proper length emerged, corresponding to
the edge length $\epsilon$ of a graph embedded in a given classical geometry.
Here $\epsilon$ is explored in more detail. $\epsilon$ at the Earth's surface
is found to lie between 100 $\mu $m and 0.7 m. The implied quantum fluctuating
space-time strain amplitude and noise spectrum are estimated to be $4\; 1/2$
orders smaller than the current experimental detectability. However, such a
macroscopic $\epsilon $ makes regularization of the semiclassical
electromagnetic Hamiltonian problematic for photon wavelengths shorter than
$\epsilon$. The origin of a large $\epsilon$ is traced to an edge-wise tensor
product of independent edge-based coherent states for the whole graph state.
This provides physical grounds for recently proposed collective coherent
states, where $\epsilon$ acquires the interpretation of a sliding scale. A new
proper distance $\xi$ emerges as the characteristic length of semiclassical
LQG. $\xi$ will affect the LQG photon vacuum dispersion relations, and is also
accessible to current measurements of space-time strain. Matter interactions
may also affect $\xi$.


title: Monte Carlo study of the XY-model on Sierpnski carpet

abstract:
  We have performed a Monte Carlo study of the classical XY-model on a Sierpi\'
nski carpet, which is a planar fractal structure with infinite order of
ramification and fractal dimension 1.8928. We employed the Wolff cluster
algorithm in our simulations and our results, in particular those for the
susceptibility and the helicity modulus, indicate the absence of
finite-temperature Berezinskii-Kosterlitz-Thouless (BKT) transition in this
system.


title:
Business and social evaluation of denial of service attacks of
  communications networks in view of scaling economic counter-measures

abstract:
  This paper gives an analytical method to determine the economic and indirect
implications of denial of service and distributed denial of service attacks. It
is based on time preference dynamics applied to the monetary mass for the
restoration of capabilities, on long term investments to rebuild capabilities,
and of the usability level of the capabilities after an attack. A simple
illustrative example is provided for a denial of service on a corporate data
centre. The needed data collection methodologies are categorized by classes of
targets. The use of the method is explained in the context of legal or policy
driven dissuasive, retaliation or compensation/ restoration actions. A concrete
set of deployment cases in mobile communications services is discussed. The
conclusion includes policy recommendations as well as information exchange
requirements.


title:
Predicting the $B -> \rho$ form factors using AdS/QCD Distribution
  Amplitudes for the $\rho$ meson

abstract:
  We use QCD light-cone sum rules (LCSR) with holographic anti de
Sitter/Chromodynamics (AdS/QCD) Distribution Amplitudes (DAs) for the $\rho$
meson to predict the form factors that govern the leading amplitudes of the
rare radiative $B -> \rho \gamma$ decay and the semileptonic decay $B -> \rho l
\nu$. We test the Isgur-Wise relation between the radiative and semileptonic
form factors. We also compute the total width (in units of $|V_{ub}|^2$) for
the semileptonic decay $B -> \rho l \nu$ as well as ratios of partial decay
widths which are independent of $|V_{ub}|$.


title: Holographic EPR Pairs, Wormholes and Radiation

abstract:
  As evidence for the ER=EPR conjecture, it has recently been observed that the
string that is holographically dual to an entangled quark-antiquark pair
separating with (asymptotically) uniform acceleration has a wormhole on its
worldsheet. We point out that a two-sided horizon and a wormhole actually
appear for much more generic quark-antiquark trajectories, which is consistent
with the fact that the members of an EPR pair need not be permanently out of
causal contact. The feature that determines whether the causal structure of the
string worldsheet is trivial or not turns out to be the emission of gluonic
radiation by the dual quark and antiquark. In the strongly-coupled gauge
theory, it is only when radiation is emitted that one obtains an unambiguous
separation of the pair into entangled subsystems, and this is what is reflected
on the gravity side by the existence of the worldsheet horizon.


title: Universal dynamics of a degenerate unitary Bose gas

abstract:
  Understanding the rich behavior that emerges from systems of interacting
quantum particles, such as electrons in materials, nucleons in nuclei or
neutron stars, the quark-gluon plasma, and superfluid liquid helium, requires
investigation of systems that are clean, accessible, and have tunable
parameters. Ultracold quantum gases offer tremendous promise for this
application largely due to an unprecedented control over interactions.
Specifically, $a$, the two-body scattering length that characterizes the
interaction strength, can be tuned to any value. This offers prospects for
experimental access to regimes where the behavior is not well understood
because interactions are strong, atom-atom correlations are important,
mean-field theory is inadequate, and equilibrium may not be reached or perhaps
does not even exist. Of particular interest is the unitary gas, where $a$ is
infinite, and where many aspects of the system are universal in that they
depend only on the particle density and quantum statistics. While the unitary
Fermi gas has been the subject of intense experimental and theoretical
investigation, the degenerate unitary Bose gas has generally been deemed
experimentally inaccessible because of three-body loss rates that increase
dramatically with increasing $a$. Here, we investigate dynamics of a unitary
Bose gas for timescales that are short compared to the loss. We find that the
momentum distribution of the unitary Bose gas evolves on timescales fast
compared to losses, and that both the timescale for this evolution and the
limiting shape of the momentum distribution are consistent with universal
scaling with density. This work demonstrates that a unitary Bose gas can be
created and probed dynamically, and thus opens the door for further exploration
of this novel strongly interacting quantum liquid.


title: Frozen Vacuum

abstract:
  Modes just outside the horizon of a typical old black hole are thermally
entangled with distant Hawking radiation. This precludes their entangled purity
with interior modes, leading to a firewall. Identifying the interior with the
distant radiation ("A=R_B", "ER=EPR") can resolve the entanglement conflict.
But the map must adjust for any interactions, or else the firewall will
reappear if the Hawking radiation scatters off the CMB. With a self-correcting
map, an infalling observer is unable to excite the vacuum near the horizon.
This allows the horizon to be locally detected and so violates the equivalence
principle.


title:
Impact of Short-Range Scattering on the Metallic Transport of Strongly
  Correlated 2D Holes in GaAs Quantum Wells

abstract:
  Understanding the non-monotonic behavior in the temperature dependent
resistance, R(T), of strongly correlated two-dimensional (2D) carriers in clean
semiconductors has been a central issue in the studies of 2D metallic states
and metal-insulator-transitions. We have studied the transport of high mobility
2D holes in 20nm wide GaAs quantum wells (QWs) with varying short-range
disorder strength by changing the Al fraction x in the Al_xGa_{1-x}As barrier.
Via varying the short range interface roughness and alloy scattering, it is
observed that increasing x suppresses both the strength and characteristic
temperature scale of the 2D metallicity, pointing to the distinct role of
short-range versus long-range disorder in the 2D metallic transport in this
correlated 2D hole system with interaction parameter r_s~ 20.


title:
Spherical collapse in Galileon gravity: fifth force solutions, halo mass
  function and halo bias

abstract:
  We study spherical collapse in the Quartic and Quintic Covariant Galileon
gravity models within the framework of the excursion set formalism. We derive
the nonlinear spherically symmetric equations in the quasi-static and
weak-field limits, focusing on model parameters that fit current CMB, SNIa and
BAO data. We demonstrate that the equations of the Quintic model do not admit
physical solutions of the fifth force in high density regions, which prevents
the study of structure formation in this model. For the Quartic model, we show
that the effective gravitational strength deviates from unity at late times ($z
\lesssim 1$), becoming larger if the density is low, but smaller if the density
is high. This shows that the Vainshtein mechanism at high densities is not
enough to screen all of the modifications of gravity. This makes halos that
collapse at $z \lesssim 1$ feel an overall weaker gravity, which suppresses
halo formation. However, the matter density in the Quartic model is higher than
in standard $\Lambda$CDM, which boosts structure formation and dominates over
the effect of the weaker gravity. In the Quartic model there is a significant
overabundance of high-mass halos relative to $\Lambda$CDM. Dark matter halos
are also less biased than in $\Lambda$CDM, with the difference increasing
appreciably with halo mass. However, our results suggest that the bias may not
be small enough to fully reconcile the predicted matter power spectrum with LRG
clustering data.


title:
Sailfish: Alignment-free Isoform Quantification from RNA-seq Reads using
  Lightweight Algorithms

abstract:
  RNA-seq has rapidly become the de facto technique to measure gene expression.
However, the time required for analysis has not kept up with the pace of data
generation. Here we introduce Sailfish, a novel computational method for
quantifying the abundance of previously annotated RNA isoforms from RNA-seq
data. Sailfish entirely avoids mapping reads, which is a time-consuming step in
all current methods. Sailfish provides quantification estimates much faster
than existing approaches (typically 20-times faster) without loss of accuracy.


title:
Theory of metallic double perovskites with spin orbit coupling and
  strong correlations; application to ferrimagnetic Ba2FeReO6

abstract:
  We consider a model of the double perovskite Ba2FeReO6, a room temperature
ferrimagnet with correlated and spin-orbit coupled Re t2g electrons moving in
the background of Fe moments stabilized by Hund's coupling. We show that for
such 3d/5d double perovskites, strong correlations on the 5d-element (Re) are
essential in driving a half-metallic ground state. Incorporating both strong
spin-orbit coupling and the Hubbard repulsion on Re leads to a band structure
consistent with ab initio calculations. Using our model, we find a large spin
polarization at the Fermi level, and obtain a semi-quantitative understanding
of the saturation magnetization of Ba2FeReO6, as well as X-ray magnetic
circular dichroism data indicating a significant orbital magnetization. Based
on the orbital populations obtained in our theory, we predict a specific doping
dependence to the tetragonal distortion accompanying ferrimagnetic order.
Finally, the combination of a net magnetization and spin-orbit interactions is
shown to induce Weyl nodes in the band structure, and we predict a significant
intrinsic anomalous Hall effect in hole-doped Ba2FeReO6. The uncovered
interplay of strong correlations and spin-orbit coupling lends partial support
to our previous work, which used a local moment description to capture the spin
wave dispersion found in neutron scattering measurements. Our work is of broad
interest for understanding metallic 4d-based and 5d-based double perovskites
which are of fundamental interest and of possible relevance to spintronic
applications.


title:
Regional variations in the dense gas heating and cooling in M51 from
  Herschel far-infrared spectroscopy

abstract:
  We present Herschel PACS and SPIRE spectroscopy of the most important
far-infrared cooling lines in M51, [CII](158 \mu m), [NII](122 & 205 \mu m),
[OI](63 and 145 \mu m) and [OIII](88 \mu m). We compare the observed flux of
these lines with the predicted flux from a photon dominated region model to
determine characteristics of the cold gas such as density, temperature and the
far-ultraviolet radiation field, G_0, resolving details on physical scales of
roughly 600 pc. We find an average [CII]/F_TIR of 4 x 10^{-3}, in agreement
with previous studies of other galaxies. A pixel-by-pixel analysis of four
distinct regions of M51 shows a radially decreasing trend in both the
far-ultraviolet (FUV) radiation field, G_0 and the hydrogen density, n, peaking
in the nucleus of the galaxy, then falling off out to the arm and interarm
regions. We see for the first time that the FUV flux and gas density are
similar in the differing environments of the arm and interarm regions,
suggesting that the inherent physical properties of the molecular clouds in
both regions are essentially the same.


title:
ALMA observations of the variable 12CO/13CO ratio around the asymptotic
  giant branch star R Sculptoris

abstract:
  [abridged] The 12CO/13CO ratio is often used as a measure of the 12C/13C
ratio in the circumstellar environment, carrying important information about
the stellar nucleosynthesis. External processes can change the 12CO and 13CO
abundances, and spatially resolved studies of the 12CO/13CO ratio are needed to
quantify the effect of these processes on the globally determined values.
Additionally, such studies provide important information on the conditions in
the circumstellar environment. The detached-shell source R Scl, displaying CO
emission from recent mass loss, in a binary-induced spiral structure as well as
in a clumpy shell produced during a thermal pulse, provides a unique laboratory
for studying the differences in CO isotope abundances throughout its recent
evolution. We observed both the 12CO(J=3-2) and the 13CO(J=3-2) line using
ALMA. We find significant variations in the 12CO/13CO intensity ratios and
consequently in the abundance ratios. The average CO isotope abundance ratio is
at least a factor three lower in the shell (~19) than that in the present-day
(<300 years) mass loss (>60). Additionally, variations in the ratio of more
than an order of magnitude are found in the shell itself. We attribute these
variations to the competition between selective dissociation and isotope
fractionation in the shell, of which large parts cannot be warmer than ~35 K.
However, we also find that the 12CO/13CO ratio in the present-day mass loss is
significantly higher than the 12C/13C ratio determined in the stellar
photosphere from molecular tracers (~19). The origin of this discrepancy is
still unclear, but we speculate that it is due to an embedded source of
UV-radiation that is primarily photo-dissociating 13CO. This radiation source
could be the hitherto hidden companion. Alternatively, the UV-radiation could
originate from an active chromosphere of R Scl itself....


title:
Searching for Oscillations in the Primordial Power Spectrum:
  Perturbative Approach (Paper I)

abstract:
  In this first of two papers, we present a new method for searching for
oscillatory features in the primordial power spectrum. A wide variety of models
predict these features in one of two different flavors: logarithmically spaced
oscillations and linearly spaced oscillations. The proposed method treats the
oscillations as perturbations on top of the scale-invariant power spectrum,
allowing us to vary all cosmological parameters. This perturbative approach
reduces the computational requirements for the search as the transfer functions
and their derivatives can be precomputed. We show that the most significant
degeneracy in the analysis is between the distance to last scattering and the
overall amplitude at low frequencies. For models with logarithmic oscillations,
this degeneracy leads to an uncertainty in the phase. For linear spaced
oscillations, it affects the frequency of the oscillations. In this first of
two papers, we test our code on simulated Planck-like data, and show we are
able to recover fiducial input oscillations with an amplitude of a few times
order 10^{-2}. We apply the code to WMAP9-year data and confirm the existence
of two intriguing resonant frequencies for log spaced oscillations. For linear
spaced oscillations we find a single resonance peak. We use numerical
simulations to assess the significance of these features and conclude that the
data do not provide compelling evidence for the existence of oscillatory
features in the primordial spectrum.


title:
Searching for Oscillations in the Primordial Power Spectrum: Constraints
  from Planck (Paper II)

abstract:
  We apply our recently developed code to search for resonance features in the
Planck CMB temperature data. We search both for log spaced oscillations or
linear spaced oscillations and compare our findings with results of our WMAP9
analysis and the Planck team analysis. While there are hints of log spaced
resonant features present in the WMAP9 data, the significance of these features
weaken with more data. With more accurate small scale measurements, we also
find that the best fit frequency has shifted and the amplitude has been
reduced. We confirm the presence of a several low frequency peaks, earlier
identified by the Planck team, but with a better improvement of fit (delta
chi^2 ~ 12). We further investigate this improvement by allowing the lensing
potential to vary as well, showing mild correlation between the amplitude of
the oscillations and the lensing amplitude. We find that the improvement of the
fit increases even more (delta chi^2 ~ 14) for the low frequencies that modify
the spectrum in a way that mimics the lensing effect. Since these features were
not present in the WMAP data, they are primarily due to better measurements of
Planck at small angular scales. For linear spaced oscillations we find a
maximum delta chi^2 ~ 13 scanning two orders of magnitude in frequency space,
and the biggest improvements are at extremely high frequencies. We recover a
best fit frequency very close to the one found in WMAP9, which confirms that
the fit improvement is driven by low l. Further comparisons with WMAP9 show
Planck contains many more features, both for linear and log space oscillations,
but with a smaller improvement of fit. We discuss the improvement as a function
of the number of modes and study the effect of the 217 GHz map, which appears
to drive most of the improvement for log spaced oscillations. We conclude that
none of the detected features are statistically significant.


title:
Quantifying mass segregation and new core radii for 54 milky way
  globular clusters

abstract:
  We present core radii for 54 Milky Way globular clusters determined by
fitting King-Michie models to cumulative projected star count distributions. We
find that fitting star counts rather than surface brightness profiles produces
results that differ significantly due to the presence of mass segregation. The
sample in each cluster is further broken down into various mass groups, each of
which is fit independently, allowing us to determine how the concentration of
each cluster varies with mass. The majority of the clusters in our sample show
general agreement with the standard picture that more massive stars will be
more centrally concentrated. We find that core radius vs. stellar mass can be
fit with a two parameter power-law. The slope of this power-law is a value that
describes the amount of mass segregation present in the cluster, and is
measured independently of our distance from the cluster. This value correlates
strongly with the core relaxation time and physical size of each cluster.
Supplementary figures are also included showing the best fits and likelihood
contours of fit parameters for all 54 clusters.


title:
Galaxy pairs in the Sloan Digital Sky Survey - VIII: The observational
  properties of post-merger galaxies

abstract:
  In order to investigate the effects of galaxy mergers throughout the
interaction sequence, we present a study of 10,800 galaxies in close pairs and
a smaller sample of 97 post-mergers identified in the Sloan Digital Sky Survey.
We find that the average central star formation rate (SFR) enhancement (x 3.5)
and the fraction of starbursts (20 per cent) peak in the post-merger sample.
The post-mergers also show a stronger deficit in gas phase metallicity than the
closest pairs, being more metal-poor than their control by -0.09 dex. Combined
with the observed trends in SFR and the timescales predicted in merger
simulations, we estimate that the post-mergers in our sample have undergone
coalescence within the last few hundred Myr. In contrast with the incidence of
star-forming galaxies, the frequency of active galactic nuclei (AGN) peaks in
the post-mergers, outnumbering AGN in the control sample by a factor of 3.75.
Moreover, amongst the galaxies that host an AGN, the black hole accretion rates
in the closest pairs and post-mergers are higher by a factor of ~3 than AGN in
the control sample. These results are consistent with a picture in which star
formation is initiated early on in the encounter, with AGN activity peaking
post-coalescence.


title:
Multidimensional optomechanical cantilevers for high frequency atomic
  force microscopy

abstract:
  High-frequency atomic force microscopy has enabled extraordinary new science
through large bandwidth, high speed measurements of atomic and molecular
structures. However, traditional optical detection schemes restrict the
dimensions, and therefore the frequency, of the cantilever - ultimately setting
a limit to the time resolution of experiments. Here we demonstrate
optomechanical detection of low-mass, high-frequency nanomechanical cantilevers
(up to 20 MHz) that surpass these limits, anticipating their use for
single-molecule force measurements. These cantilevers achieve 2 fm / sqrt(Hz)
displacement noise floors, and force sensitivity down to 132 aN / sqrt(Hz).
Furthermore, the ability to resolve both in-plane and out-of-plane motion of
our cantilevers opens the door for ultrasensitive multidimensional force
spectroscopy, and optomechanical interactions, such as tuning of the cantilever
frequency in situ, provide new opportunities in high-speed, high-resolution
experiments.


title: Multifrequency studies of the narrow-line Seyfert 1 galaxy SBS 0846+513

abstract:
  The narrow-line Seyfert 1 galaxy SBS 0846+513 was first detected by the Large
Area Telescope (LAT) on-board Fermi in 2011 June-July when it underwent a
period of flaring activity. Since then, as Fermi continues to accumulate data
on this source, its flux has been monitored on a daily basis. Two further
gamma-ray flaring episodes from SBS 0846+513 were observed in 2012 May and
August, reaching a daily peak flux integrated above 100 MeV of (50+/-12)x10^-8
ph/cm^2/s, and (73+/-14)x10^-8 ph/cm^2/s on May 24 and August 7, respectively.
Three outbursts were detected at 15 GHz by the Owens Valley Radio Observatory
40-m telescope in 2012 May, 2012 October, and 2013 January, suggesting a
complex connection with the gamma-ray activity. The most likely scenario
suggests that the 2012 May gamma-ray flare may not be directly related to the
radio activity observed over the same period, while the two gamma-ray flaring
episodes may be related to the radio activity observed at 15 GHz in 2012
October and 2013 January. The gamma-ray flare in 2012 May triggered Swift
observations that confirmed that SBS 0846+513 was also exhibiting high activity
in the optical, UV and X-ray bands, thus providing a firm identification
between the gamma-ray source and the lower-energy counterpart. We compared the
spectral energy distribution (SED) of the flaring state in 2012 May with that
of a quiescent state. The two SEDs, modelled as an external Compton component
of seed photons from a dust torus, could be fitted by changing the electron
distribution parameters as well as the magnetic field. No significant evidence
of thermal emission from the accretion disc has been observed. Interestingly,
in the 5 GHz radio luminosity vs. synchrotron peak frequency plot SBS 0846+513
seems to lie in the flat spectrum radio quasar part of the so-called `blazar
sequence'.


title:
The Second Main Theorem Vector for the modular regular representation of
  $C_2$

abstract:
  We study the ring of invariants for a finite dimensional representation $V$
of the group $C_2$ of order 2 in characteristic $2$. Let $\sigma$ denote a
generator of $C_2$ and $\{x_1,y_1 \dots, x_m,y_m\}$ a basis of $V^*$. Then
$\sigma(x_i) = x_i$, and $\sigma(y_i) = y_i + x_i$. To our knowledge, this ring
(for any prime $p$) was first studied by David Richman in 1990. He gave a first
main theorem for $(V_2, C_2)$, that is, he proved that the ring of invariants
when $p=2$ is generated by $\{x_i, N_i = y_i^2 + x_iy_i, tr(A) | 2 \le |A| \le
m\}$ where $A \subset \{0,1\}^m$, $y^A = y_1^{a_1} y_2^{a_2} \cdots y_m^{a_m}$
and $tr(A) = y^A + (y_1+x_1)^{a_1}(y_2+x_2)^{a_2} \cdots (y_m+x_m)^{a_m}.$ In
this paper, we prove the second main theorem for $(V_2, C_2)$, that is, we show
that all relations between these generators are generated by relations of type
I: $\sum_{I \subset A } x^I tr(A-I)$ and of type II: $tr(A) tr(B) = \sum_{L <
I} x^{I-L} N^L tr(I-L+J+K) + N^I \sum_{L < J} x^{J-L} tr(L+K)$ for all $m$. We
also derive relations of type III which are simpler and can be used in place of
the relations of type II.


title: Effective electrostatic interactions in mixtures of charged colloids

abstract:
  We present a theory of effective electrostatic interactions in polydisperse
suspensions of charged macroions, generalizing to mixtures a theory previously
developed for monodisperse suspensions. Combining linear response theory with a
random phase approximation for microion correlations, we coarse-grain the
microion degrees of freedom to derive general expressions for effective
macroion-macroion pair potentials and a one-body volume energy. For model
mixtures of charged hard-sphere colloids, we give explicit analytical
expressions. The resulting effective pair potentials have the same general form
as predicted by linearized Poisson-Boltzmann theory, but consistently
incorporate dependence on macroion density and excluded volume via the Debye
screening constant. The volume energy, which depends on the average macroion
density, contributes to the free energy and so can influence thermodynamic
properties of deionized suspensions. To validate the theory, we compute radial
distribution functions of binary mixtures of oppositely charged colloidal
macroions from molecular dynamics simulations of the coarse-grained model (with
implicit microions), taking effective pair potentials as input. Our results
agree closely with corresponding results from more computationally intensive
Monte Carlo simulations of the primitive model (with explicit microions).
Simulations of a mixture with large size and charge asymmetries indicate that
charged nanoparticles can enhance electrostatic screening of charged colloids.
The theory presented here lays a foundation for future large-scale modeling of
complex mixtures of charged colloids, nanoparticles, and polyelectrolytes.


title: Tracking Down the Top Quark Forward-Backward Asymmetry with Monotops

abstract:
  We revisit the possibility that the top quark forward-backward asymmetry
arises from the on-shell production and decay of scalar top partners to
top-antitop pairs with missing transverse energy. Although the asymmetry is
produced by t-channel exchange of a light mediator, the model remains
unconstrained by low energy atomic parity violation tests. An interesting
connection to the active neutrino sector through a Type-I seesaw operator helps
to evade stringent monojet constraints and opens up a richer collider
phenomenology. After performing a global fit to top data from both the Tevatron
and the LHC, we obtain a viable region of parameter space consistent with all
phenomenological and collider constraints. We also discuss the discovery
potential of a predicted monotop signal and related lepton charge asymmetry at
the LHC.


title:
Heavy dust obscuration of z=7 galaxies in a cosmological hydrodynamic
  simulation

abstract:
  Hubble Space Telescope observations with Wide Field Camera 3/IR reveal that
galaxies at z~7 have very blue ultraviolet (UV) colors, consistent with these
systems being dominated by young stellar populations with moderate or little
attenuation by dust. We investigate UV and optical properties of the high-z
galaxies in the standard cold dark matter model using a high-resolution
adaptive mesh refinement cosmological hydrodynamic simulation. For this
purpose, we perform panchromatic three-dimensional dust radiative transfer
calculations on 198 galaxies of stellar mass 5x10^8-3x10^{10} Msun with three
parameters, the dust-to-metal ratio, the extinction curve, and the fraction of
directly escaped light from stars (\fesc). Our stellar mass function is found
to be in broad agreement with Gonzalez et al., independent of these parameters.
We find that our heavily dust-attenuated galaxies (A_V~1.8) can also reasonably
match modest UV-optical colors, blue UV slopes, as well as UV luminosity
functions, provided that a significant fraction (~10%) of light directly
escapes from them. The observed UV slope and scatter are better explained with
an Small Magellanic Cloud-type extinction curve, whereas Milky Way-type dust
predicts too blue UV colors due to the 2175A bump. We expect that upcoming
observations by ALMA will be able to test this heavily obscured model.


title: Randomization and the Gross-Pitaevskii hierarchy

abstract:
  We study the Gross-Pitaevskii hierarchy on the spatial domain $\mathbb{T}^3$.
By using an appropriate randomization of the Fourier coefficients in the
collision operator, we prove an averaged form of the main estimate which is
used in order to contract the Duhamel terms that occur in the study of the
hierarchy. In the averaged estimate, we do not need to integrate in the time
variable. An averaged spacetime estimate for this range of regularity exponents
then follows as a direct corollary. The range of regularity exponents that we
obtain is $\alpha>\frac{3}{4}$. It was shown in our previous joint work with
Gressman that the range $\alpha>1$ is sharp in the corresponding deterministic
spacetime estimate. This is in contrast to the non-periodic setting, which was
studied by Klainerman and Machedon, in which the spacetime estimate is known to
hold whenever $\alpha \geq 1$. The goal of our paper is to extend the range of
$\alpha$ in this class of estimates in a \emph{probabilistic sense}.
  We use the new estimate and the ideas from its proof in order to study
randomized forms of the Gross-Pitaevskii hierarchy. More precisely, we consider
hierarchies similar to the Gross-Pitaevskii hierarchy, but in which the
collision operator has been randomized. For these hierarchies, we show
convergence to zero in low regularity Sobolev spaces of Duhamel expansions of
fixed deterministic density matrices. We believe that the study of the
randomized collision operators could be the first step in the understanding of
a nonlinear form of randomization.


title:
Quantum kinetics of spinning neutral particles: General theory and Spin
  wave dispersion

abstract:
  Plasma physics give an example of physical system of particles with the long
range interaction. At small velocity of particles we can consider the plasma
approximately as a system of particles with the Coulomb interaction. The
Coulomb interaction is isotropic. Systems of spinning neutral particles have
long-range anisotropic interparticle interaction. So, they can reveal more
reach properties than plasma. Furthermore for studying of systems of spinning
particles we can develop kinetic and hydrodynamic methods analogous to used for
the plasma. We derive kinetic equations by a new method, which is the
generalization of the many-particle quantum hydrodynamics. Obtained set of
kinetic equations is truncated, so we have closed set of two equations. One of
them is the kinetic equation for quantum distribution function. The second
equation is the equation for the spin-distribution. Which describes the spin
kinetic evolution and gives contribution in time evolution of the distribution
function. Our method allows to obtain equations as for three dimensional system
of particles and for low dimensional systems. So, we consider spin waves in
three- and two dimensional systems of neutral spinning particles.

categories: physics.plasm-ph cond-mat.quant-gas cond-mat.stat-mech quant-ph


title: Gravitational Dynamics From Entanglement "Thermodynamics"

abstract:
  In a general conformal field theory, perturbations to the vacuum state obey
the relation \delta S = \delta E, where \delta S is the change in entanglement
entropy of an arbitrary ball-shaped region, and \delta E is the change in
"hyperbolic" energy of this region. In this note, we show that for holographic
conformal field theories, this relation, together with the holographic
connection between entanglement entropies and areas of extremal surfaces and
the standard connection between the field theory stress tensor and the boundary
behavior of the metric, implies that geometry dual to the perturbed state
satisfies Einstein's equations expanded to linear order about pure AdS.


title:
Persistent spin excitations in doped antiferromagnets revealed by
  resonant inelastic light scattering

abstract:
  How coherent quasiparticles emerge by doping quantum antiferromagnets is a
key question in correlated electron systems, whose resolution is needed to
elucidate the phase diagram of copper oxides. Recent resonant inelastic X-ray
scattering (RIXS) experiments in hole-doped cuprates have purported to measure
high-energy collective spin excitations that persist well into the overdoped
regime and bear a striking resemblance to those found in the parent compound,
challenging the perception that spin excitations should weaken with doping and
have a diminishing effect on superconductivity. Here we show that RIXS at the
Cu L3-edge indeed provides access to the spin dynamical structure factor once
one considers the full influence of light polarization. Further we demonstrate
that high-energy spin excitations do not correlate with the doping dependence
of Tc, while low-energy excitations depend sensitively on doping and show
ferromagnetic correlations. This suggests that high-energy spin excitations are
marginal to pairing in cuprate superconductors.


title:
The dynamics of internal gravity waves in the ocean: theory and
  applications

abstract:
  In this paper we consider fundamental processes of the disturbance and
propagation of internal gravity waves in the ocean modeled as a vertically
stratified, horizontally non-uniform, and non-stationary medium. We develop
asymptotic methods for describing the wave dynamics by generalizing the
spatiotemporal ray-tracing method (a geometrical optics method). We present
analytical and numerical algorithms for calculating the internal gravity wave
fields using actual ocean parameters such as physical characteristics of the
sea water, topography of its floor, etc. We demonstrate that our mathematical
models can realistically describe the internal gravity wave dynamics in the
ocean. Our numerical and analytical results show that the internal gravity
waves have a significant impact on underwater objects in the ocean.

categories: physics.flu-dyn math-ph math.MP physics.ao-ph


title:
Consequences of Mechanical and Radiative Feedback from Black Holes in
  Disc Galaxy Mergers

abstract:
  We study the effect of AGN mechanical and radiation feedback on the formation
of bulge dominated galaxies via mergers of disc galaxies. The merging galaxies
have mass-ratios of 1:1 to 6:1 and include pre-existing hot gaseous halos to
properly account for the global impact of AGN feedback. Using smoothed particle
hydrodynamics simulation code (GADGET-3) we compare three models with different
AGN feedback models: (1) no black hole and no AGN feedback; (2) thermal AGN
feedback; and (3) mechanical and radiative AGN feedback. The last model is
motivated by observations of broad line quasars which show winds with initial
velocities of $v_w \ge$ 10,000 km/s and also heating associated with the
central AGN X-ray radiation. The primary changes in gas properties due to
mechanical AGN feedback are lower thermal X-ray luminosity from the final
galaxy - in better agreement with observations - and galactic outflows with
higher velocity $\sim 1000$ km/s similar to recent direct observations of
nearby merger remnants. The kinetic energy of the outflowing gas is a factor of
$\sim$ 20 higher than in the thermal feedback case. All merger remnants with
momentum-based AGN feedback with $v_w \sim 10,000$ km/s and $\epsilon_w=2
\times 10^{-3}$, independent of their progenitor mass-ratios, reproduce the
observed relations between stellar velocity dispersion and black hole mass
($M_{\rm bh} - \sigma$) as well as X-ray luminosity ($L_X - \sigma$) with
$10^{37.5}$ erg/s $\lesssim L_X (0.3-8~{\rm keV}) \lesssim 10^{39.2}$ erg/s for
velocity dispersions in the range of 120 km/s $\lesssim \sigma \lesssim$ 190
km/s. In addition, the mechanical feedback produces a much greater AGN
variability. We also show that gas is more rapidly and impulsively stripped
from the galactic centres driving a moderate increase in galaxy size and
decrease in central density with the mechanical AGN feedback model.


title:
Probing the Gamma-Ray Burst Rate with Trigger Simulations of the Swift
  Burst Alert Telescope

abstract:
  The long gamma-ray burst (GRB) rate is essential for revealing the connection
between GRBs, supernovae and stellar evolution. Additionally, the GRB rate at
high redshift provides a strong probe of star formation history in the early
universe. While hundreds of GRBs are observed by Swift, it remains difficult to
determine the intrinsic GRB rate due to the complex trigger algorithm of Swift.
Current studies usually approximate the Swift trigger algorithm by a single
detection threshold. However, unlike the previously flown GRB instruments,
Swift has over 500 trigger criteria based on photon count rate and additional
image threshold for localization. To investigate possible systematic biases and
explore the intrinsic GRB properties, we developed a program that is capable of
simulating all the rate trigger criteria and mimicking the image trigger
threshold. We use this program to search for the intrinsic GRB rate. Our
simulations show that adopting the complex trigger algorithm of Swift increases
the detection rate of dim bursts. As a result, we find that either the GRB rate
is much higher than previously expected at large redshift, or the luminosity
evolution is non-negligible. We will discuss the best results of the GRB rate
in our search, and their impact on the star-formation history.


title:
Mechanical cell-matrix feedback explains pairwise and collective
  endothelial cell behavior in vitro

abstract:
  In vitro cultures of endothelial cells are a widely used model system of the
collective behavior of endothelial cells during vasculogenesis and
angiogenesis. When seeded in an extracellular matrix, endothelial cells can
form blood vessel-like structures, including vascular networks and sprouts.
Endothelial morphogenesis depends on a large number of chemical and mechanical
factors, including the compliancy of the extracellular matrix, the available
growth factors, the adhesion of cells to the extracellular matrix, cell-cell
signaling, etc. Although various computational models have been proposed to
explain the role of each of these biochemical and biomechanical effects, the
understanding of the mechanisms underlying in vitro angiogenesis is still
incomplete. Most explanations focus on predicting the whole vascular network or
sprout from the underlying cell behavior, and do not check if the same model
also correctly captures the intermediate scale: the pairwise cell-cell
interactions or single cell responses to ECM mechanics. Here we show, using a
hybrid cellular Potts and finite element computational model, that a single set
of biologically plausible rules describing (a) the contractile forces that
endothelial cells exert on the ECM, (b) the resulting strains in the
extracellular matrix, and (c) the cellular response to the strains, suffices
for reproducing the behavior of individual endothelial cells and the
interactions of endothelial cell pairs in compliant matrices. With the same set
of rules, the model also reproduces network formation from scattered cells, and
sprouting from endothelial spheroids. Combining the present mechanical model
with aspects of previously proposed mechanical and chemical models may lead to
a more complete understanding of in vitro angiogenesis.


title: On the internal gravity waves in the stratified ocean with shear flows

abstract:
  In this paper, we consider a fundamental problem of describing the dynamics
of internal gravity waves in the stratified ocean with shear flows. We develop
an asymptotic representation of the wave fields in terms of the Green's
functions. We explore the far field of the internal gravity waves generated by
disturbing sources, and propose asymptotic algorithms for calculating its
dynamics.


title:
Comparative study of nuclear effects in polarized electron scattering
  from 3He

abstract:
  We present a detailed analysis of nuclear effects in inclusive electron
scattering from polarized 3He nuclei for polarization asymmetries, structure
functions and their moments, both in the nucleon resonance and deep-inelastic
regions. We compare the results of calculations within the weak binding
approximation at finite Q^2 with the effective polarization ansatz often used
in experimental data analyses, and explore the impact of \Delta\ components in
the nuclear wave function and nucleon off-shell corrections on extractions of
the free neutron structure. Using the same framework we also make predictions
for the Q^2 dependence of quasielastic scattering from polarized 3He, data on
which can be used to constrain the spin-dependent nuclear smearing functions in
3He.


title:
McGill University M. Sc. Thesis: Topological Superconductivity without
  Proximity Effect

abstract:
  The search for a Majorana Fermion has been an area of intense interest in
condensed matter research of late. This elusive particle, predicted to exist in
1937, has been sought after for both fundamental and practical reasons. On the
fundamental level, no particle to date has been observed to be a Majorana
fermion, meanwhile on the practical level a Majorana fermion, if found, would
represent a non-abelian anyon and could thus be used to build a quantum
computer. The search for a Majorana Fermion has recently shifted to topological
superconductivity. Topological superconductors are categorized by the
nontrivial wind- ing of their order parameter phase and for this reason are
expected to support Majorana Fermions in their vortex cores. Owing to this, the
study of topological superconductors has intensified in recent years. Current
proposals for a device that may behave as a topological superconductor are
based on semiconductor heterostructures, where the spin-orbit coupled bands of
a semiconductor are split by a band gap or Zeeman field and superconductivity
is induced by proximity to a conventional superconductor. In this setup,
topological superconductivity is obtained in the semiconductor layer and the
proposed heterostructures typically include two or three layers of different
materials. In this thesis we propose a simplification to these types of
devices, suggesting a way in which the superconducting layer can be replaced.
Part of our proposal includes a model Hamiltonian for these types of systems.
This thesis will also develop several different methods to analyze this model
Hamiltonian in various different parameter regimes with the ultimate goal of
classifying its topology.


title: Refined intersection homology on non-Witt spaces

abstract:
  We develop a generalization to non-Witt spaces of the intersection homology
theory of Goresky-MacPherson. The second author has described the self-dual
sheaves compatible with intersection homology, and the other authors have
described a generalization of Cheeger's L2 de Rham cohomology. In this paper we
extend both of these cohomologies by describing all sheaf complexes in the
derived category of constructible sheaves that are compatible with middle
perversity intersection cohomology, though not necessarily self-dual. On
Thom-Mather stratified spaces this refined intersection cohomology theory
coincides with the analytic de Rham theory.


title: Luminosity Upgrades for ILC

abstract:
  The possibility of increasing the luminosity for the ILC at Ecm < 350 GeV
centre-of-mass by increasing the beam power are considered. It will be shown
that an approximately constant luminosity can be achieved across the centre of
mass energy range (250-500 GeV) without exceeding the installed AC power for
500 GeV operation. Overall a factor of four in luminosity over the published
baseline could be achieved at 250 GeV resulting in 3*10**34 cm-2s-1. The
implications for the damping rings and positron source are also briefly
discussed.


title:
Using Inksurvey with Pen-enabled Mobile Devices for Real-time Formative
  Assessment I: Applications in Diverse Educational Enviroments

abstract:
  InkSurvey is free, web-based software designed to facilitate the collection
of real-time formative assessment. Using this tool, the instructor can embed
formative assessment in the instruction process by posing an open-format
question. Students equipped with pen-enabled mobile devices (tablet PCs, iPads,
Android devices including some smartphones) are then actively engaged in their
learning as they use digital ink to draw, sketch, or graph their responses.
When the instructor receives these responses instantaneously, it provides
insights into student thinking and what the students do and do not know.
Subsequent instruction can then repair and refine student understanding in a
very timely manner.
  Although this pedagogical tool is appealing because of its broad theoretical
foundations, the cost of pen-enabled mobile technology was until recently a
significant barrier to widely implementing this teaching model. However, less
expensive tablets, iPads, and Android devices are now filling the market (and
student backpacks) and greatly lowering that barrier.
  To illustrate the wide applicability of this use of technology, we report a
series of seven vignettes featuring instructors of diverse subjects
(mathematics, food chemistry, physics, biology, and chemical engineering), with
students using diverse pen-enabled mobile devices (tablet PCs, iPads, and
Android 4.0 tablets), in diverse educational environments (K-12, community
college, publicly-funded engineering university, private university, graduate
school), in two countries (United States and Mexico). In a companion paper,
each instructor also shares some data, insights, and/or conclusions from their
experiences regarding the effectiveness of this tool.


title:
On the causal interpretation of acyclic mixed graphs under multivariate
  normality

abstract:
  In multivariate statistics, acyclic mixed graphs with directed and bidirected
edges are widely used for compact representation of dependence structures that
can arise in the presence of hidden (i.e., latent or unobserved) variables.
Indeed, under multivariate normality, every mixed graph corresponds to a set of
covariance matrices that contains as a full-dimensional subset the covariance
matrices associated with a causally interpretable acyclic digraph. This digraph
generally has some of its nodes corresponding to hidden variables. We seek to
clarify for which mixed graphs there exists an acyclic digraph whose hidden
variable model coincides with the mixed graph model. Restricting to the
tractable setting of chain graphs and multivariate normality, we show that
decomposability of the bidirected part of the chain graph is necessary and
sufficient for equality between the mixed graph model and some hidden variable
model given by an acyclic digraph.


title:
Using Inksurvey with Pen-enabled Movile Devices for Real-time Formative
  Assessment II: Indications of Effectiveness in Diverse Educational
  Environments

abstract:
  InkSurvey is free, web-based software designed to facilitate the collection
of real-time formative assessment. Using this tool, the instructor can embed
formative assessment in the instruction process by posing an open-format
question. Students equipped with pen-enabled mobile devices are then actively
engaged in their learning as they use digital ink to draw, sketch, or graph
their responses. When the instructor receives these responses instantaneously,
it provides insights into student thinking and what the students do and do not
know. Subsequent instruction can then repair and refine student understanding
in a very timely manner.
  In a companion paper, we illustrate the wide applicability of this use of
technology by reporting a series of seven vignettes featuring instructors of
diverse subjects (physics, mathematics, chemical engineering, food science, and
biology), with students using diverse pen-enabled mobile devices (tablet PCs,
iPads, and Android 4.0 tablets/smartphones), in diverse educational
environments (K-12, community college, publicly-funded engineering university,
private university, and graduate school), in two countries (United States and
Mexico). In this paper, each instructor shares some data, insights, and/or
conclusions from their experiences that indicate the effectiveness of this
pedagogical model in diverse educational environments.


title: Pick Interpolation for free holomorphic functions

abstract: We prove an interpolation theorem for bounded free holomorphic functions.


title:
Strong Coupling Expansion of the Extended Hubbard Model with Spin-Orbit
  Coupling

abstract:
  We study the strong coupling limit of the extended Hubbard model in two
dimensions. The model consists of hopping, on-site interaction,
nearest-neighbor interaction, spin-orbit coupling and Zeeman spin splitting.
While the study of this model is motivated by a search for topological phases
and in particular a topological superconductor, the methodology we develop may
be useful for a variety of systems. We begin our treatment with a canonical
transformation of the Hamiltonian to an effective model which is appropriate
when the (quartic) interaction terms are larger than the (quadratic) kinetic
and spin-orbit coupling terms. We proceed by analyzing the strong coupling
model variationally. Since we are mostly interested in a superconducting phase
we use a Gutzwiller projected BCS wavefunction as our variational state. To
continue analytically we employ the Gutzwiller approximation and compare the
calculated energy with Monte-Carlo calculations. Finally we determine the
topology of the ground state and map out the topology phase diagram.


title: A note on the random greedy independent set algorithm

abstract:
  Let r be a fixed constant and let H be an r-uniform, D-regular hypergraph on
N vertices. Assume further that D > N^\epsilon for some \epsilon>0. Consider
the random greedy algorithm for forming an independent set in H. An independent
set is chosen at random by iteratively choosing vertices at random to be in the
independent set. At each step we choose a vertex uniformly at random from the
collection of vertices that could be added to the independent set (i.e. the
collection of vertices v with the property that v is not in the current
independent set I and I \cup {v} contains no edge of H). Note that this process
terminates at a maximal subset of vertices with the property that this set
contains no edge of H; that is, the process terminates at a maximal independent
set. We prove that if H satisfies certain degree and codegree conditions then
there are \Omega(N ((log N) / D)^{1/(r-1)}) vertices in the independent set
produced by the random greedy algorithm with high probability. This result
generalizes a lower bound on the number of steps in the H-free process due to
Bohman and Keevash and produces objects of interest in additive combinatorics.


title:
Multiple orbital contributions to molecular high-harmonic generation in
  an asymmetric top

abstract:
  High-order harmonic generation (HHG) in aligned linear molecules can offer
valuable information about strong-field interactions in lower-lying molecular
orbitals, but extracting this information is difficult for three-dimensional
molecular geometries. Our measurements of the asymmetric top SO2 show large
axis dependencies, which change with harmonic order. The analysis shows that
these spectral features must be due to field ionization and recombination from
multiple orbitals during HHG. We expect that HHG can probe orbital dependencies
using this approach for a broad class of asymmetric-top molecules.


title:
Numerical estimate of infinite invariant densities: application to
  Pesin-type identity

abstract:
  Weakly chaotic maps with unstable fixed points are investigated in the regime
where the invariant density is non-normalizable. We propose that the infinite
invariant density of these maps can be estimated using as the long time limit
of t^(1-alpha) rho(x, t), in agreement with earlier work of Thaler. Here rho(x,
t) is the normalizable density of particles. This definition uniquely
determines the infinite density and is a valuable tool for numerical
estimations. We use this density to estimate the subexponential separation
lambda_alpha of nearby trajectories. For a particular map introduced by Thaler
we use an analytical expression for the infinite invariant density to calculate
lambda_alpha exactly, which perfectly matches simulations without fitting.
Misunderstanding which recently appeared in the literature is removed.


title: LHC constraints on light neutralino dark matter in the MSSM

abstract:
  Light neutralino dark matter can be achieved in the Minimal Supersymmetric
Standard Model if staus are rather light, with mass around 100 GeV. We perform
a detailed analysis of the relevant supersymmetric parameter space, including
also the possibility of light selectons and smuons, and of light higgsino- or
wino-like charginos. In addition to the latest limits from direct and indirect
detection of dark matter, ATLAS and CMS constraints on electroweak-inos and on
sleptons are taken into account using a "simplified models" framework.
Measurements of the properties of the Higgs boson at 125 GeV, which constrain
amongst others the invisible decay of the Higgs boson into a pair of
neutralinos, are also implemented in the analysis. We show that viable
neutralino dark matter can be achieved for masses as low as 15 GeV. In this
case, light charginos close to the LEP bound are required in addition to light
right-chiral staus. Significant deviations are observed in the couplings of the
125 GeV Higgs boson. These constitute a promising way to probe the light
neutralino dark matter scenario in the next run of the LHC.


title: Planck Constraints on Monodromy Inflation

abstract:
  We use data from the nominal Planck mission to constrain modulations in the
primordial power spectrum associated with monodromy inflation. The largest
improvement in fit relative to the unmodulated model has \Delta\chi^2~10 and we
find no evidence for a primordial signal, in contrast to a previous analysis of
the WMAP9 dataset, for which \Delta\chi^2~20. The Planck and WMAP9 results are
broadly consistent on angular scales where they are expected to agree as far as
best-fit values are concerned. However, even on these scales the significance
of the signal is reduced in Planck relative to WMAP, and is consistent with a
fit to the noise associated with cosmic variance. Our results motivate both a
detailed comparison between the two experiments and a more careful study of the
theoretical predictions of monodromy inflation.


title: Class-preserving automorphisms of universal hyperlinear groups

abstract:
  We show that the group of class-preserving automorphisms of a universal
hyperlinear group has index 2 inside the group of all automorphisms.


title: PT-symmetry Management in Oligomer Systems

abstract:
  We study the effects of management of the PT-symmetric part of the potential
within the setting of Schr\"odinger dimer and trimer oligomer systems. This is
done by rapidly modulating in time the gain/loss profile. This gives rise to a
number of interesting properties of the system, which are explored at the level
of an averaged equation approach. Remarkably, this rapid modulation provides
for a controllable expansion of the region of exact PT-symmetry, depending on
the strength and frequency of the imposed modulation. The resulting averaged
models are analyzed theoretically and their exact stationary solutions are
translated into time-periodic solutions through the averaging reduction. These
are, in turn, compared with the exact periodic solutions of the full
non-autonomous PT-symmetry managed problem and very good agreement is found
between the two.


title:
Inflationary buildup of a vector field condensate and its cosmological
  consequences

abstract:
  Light vector fields during inflation obtain a superhorizon perturbation
spectrum when their conformal invariance is appropriately broken. Such
perturbations, by means of some suitable mechanism (e.g. the vector curvaton
mechanism), can contribute to the curvature perturbation in the Universe and
produce characteristic signals, such as statistical anisotropy, on the
microwave sky, most recently surveyed by the Planck satellite mission. The
magnitude of such characteristic features crucially depends on the magnitude of
the vector condensate generated during inflation. However, the expectation
value of this condensate has so-far been taken as a free parameter, lacking a
definite prediction or a physically motivated estimate. In this paper, we study
the stochastic evolution of the vector condensate and obtain an estimate for
its magnitude. Our study is mainly focused in the supergravity inspired case
when the kinetic function and mass of the vector boson is time-varying during
inflation, but other cases are also explored such as a parity violating axial
theory or a non-minimal coupling between the vector field and gravity. As an
example, we apply our findings in the context of the vector curvaton mechanism
and contrast our results with current observations.


title: Standardizing Interestingness Measures for Association Rules

abstract:
  Interestingness measures provide information that can be used to prune or
select association rules. A given value of an interestingness measure is often
interpreted relative to the overall range of the values that the
interestingness measure can take. However, properties of individual association
rules restrict the values an interestingness measure can achieve. An
interesting measure can be standardized to take this into account, but this has
only been done for one interestingness measure to date, i.e., the lift.
Standardization provides greater insight than the raw value and may even alter
researchers' perception of the data. We derive standardized analogues of three
interestingness measures and use real and simulated data to compare them to
their raw versions, each other, and the standardized lift.


title: Active Matter Ratchets with an External Drift

abstract:
  When active matter particles such as swimming bacteria are placed in an
asymmetric array of funnels, it has been shown that a ratchet effect can occur
even in the absence of an external drive. Here we examine active ratchets for
two dimensional arrays of funnels or L-shapes where there is also an externally
applied dc drive or drift. We show that for certain conditions, the ratchet
effect can be strongly enhanced, and that it is possible to have conditions
under which run-and-tumble particles with one run length move in the opposite
direction from particles with a different run length. For the arrays of
L-shapes, we find that the application of a drift force can enhance a
transverse rectification in the direction perpendicular to the drift. When
particle-particle steric interactions are included, we find that the ratchet
effects can be either enhanced or suppressed depending on barrier geometry,
particle run length, and particle density.


title: Nonthermal radiation of young supernova remnants: the case of Cas A

abstract:
  The processes responsible for the broad-band radiation of the young supernova
remnant Cas A are explored using a new code which is designed for a detailed
treatment of the diffusive shock acceleration of particles in nonlinear regime.
The model is based on spherically symmetric hydrodynamic equations complemented
with transport equations for relativistic particles. Electrons, protons and the
oxygen ions accelerated by forward and reverse shocks are included in the
numerical calculations. We show that the available multi-wavelength
observations in the radio, X-ray and gamma-ray bands can be best explained by
invoking particle acceleration by both forward and reversed shocks. Although
the TeV gamma-ray observations can be interpreted by interactions of both
accelerated electrons and protons/ions, the measurements by Fermi LAT at
energies below 1 GeV give a tentative preference to the hadronic origin of
gamma-rays. Then, the acceleration efficiency in this source, despite the
previous claims, should be very high; 25% of the explosion energy (or
approximately $3\cdot 10^{50}$ erg) should already be converted to cosmic rays,
mainly by the forward shock. At the same time, the model calculations do not
provide extension of the maximum energy of accelerated protons beyond 100 TeV.
In this model, the acceleration of electrons is dominated by the reverse shock;
the required $10^{48}$ erg can be achieved under the assumption that the
injection of electrons (positrons) is supported by the radioactive decay of
$^{44}$Ti.


title: Trace theories and localization

abstract:
  We show how one can twist the definition of Hochschild homology of an algebra
or a DG algebra by inserting a possibly non-additive trace functor. We then
prove that many of the usual properties of Hochschild homology survive such a
generalization. In some cases this even includes Keller's Localization Theorem.


title:
Laplacian-based generalized gradient approximations for the exchange
  energy

abstract:
  It is well known that in the gradient expansion approximation to density
functional theory (DFT) the gradient and Laplacian of the density make
interchangeable contributions to the exchange correlation (XC) energy. This is
an arbitrary "gauge" freedom for building DFT models, normally used to
eliminate the Laplacian from the generalized gradient approximation (GGA) level
of DFT development. We explore the implications of keeping the Laplacian at
this level of DFT, to develop a model that fits the known behavior of the XC
hole, which can only be described as a system average in conventional GGA. We
generate a family of exchange models that obey the same constraints as
conventional GGA's, but which in addition have a finite-valued potential at the
atomic nucleus unlike GGA's. These are tested against exact densities and
exchange potentials for small atoms, and for constraints chosen to reproduce
the SOGGA and the APBE variants of the GGA. The model reliably reproduces
exchange energies of closed shell atoms, once constraints such the local
Lieb-Oxford bound, whose effects depend upon choice of energy-density gauge,
are recast in invariant form.


title: Computational Properties of Fiction Writing and Collaborative Work

abstract:
  From the earliest days of computing, there have been tools to help shape
narrative. Spell-checking, word counts, and readability analysis, give today's
novelists tools that Dickens, Austen, and Shakespeare could only have dreamt
of. However, such tools have focused on the word, or phrase levels. In the last
decade, research focus has shifted to support for collaborative editing of
documents. This work considers more sophisticated attempts to visualise the
semantics, pace and rhythm within a narrative through data mining. We describe
real life applications in two related domains.


title: Nuclear dependences of azimuthal asymmetries in the Drell-Yan process

abstract:
  We study nuclear dependences of azimuthal asymmetries in the Drell-Yan lepton
pair production in nucleon-nucleus collisions with polarized nucleons.We use
the "maximal two-gluon correlation approximation", so that we can relate the
transverse momentum dependent quark distribution in a nucleus to that in a
nucleon by a convolution with a Gaussian broadening.We use the Gaussian ansatz
for the transverse momentum dependence of such quark distribution functions,and
obtain the numerical results for the nuclear dependences.These results show
that the averaged azimuthal asymmetries are suppressed.


title:
Photon-assisted-tunneling in a coupled double quantum dot out of thermal
  equilibrium

abstract:
  We perform photon-assisted-tunneling (PAT) experiments on a GaAs double
quantum dot device under high microwave excitation power. Photon-assisted
absorption of up to 14 photons is observed, when electron temperature (>1K) are
far above the lattice temperature. Signatures of Landau-Zener-St\"uckelberg
(LZS) interference are found even in this non-equilibrium PAT spectrum. In
addition, the charge state relaxation time T_1~8ns measured in this out of
thermal equilibrium double quantum dot is in agreement with other previous
reports.


title:
Work distribution of an expanding gas and transverse energy production
  in relativistic heavy ion collisions

abstract:
  The work distribution of an expanding extreme relativistic gas is shown to be
a gamma distribution with a different shape parameter as compared with its
non-relativistic counterpart. This implies that the shape of the transverse
energy distribution in relativistic heavy ion collisions depends on the
particle contents during the evolution of the hot and dense matter. Therefore,
transverse energy fluctuations provide additional insights into the Quark-Gluon
Plasma produced in these collisions.


title: On Borel hull operations

abstract:
  We show that some set-theoretic assumptions (for example Martin's Axiom)
imply that there is no translation invariant Borel hull operation on the family
of Lebesgue null sets and on the family of meager sets in (in R^n). We also
prove that if the meager ideal admits a monotone Borel hull operation, then
there is also a monotone Borel hull operation on the sigma-algebra of sets with
the property of Baire.


title:
Comment on "robustness and regularization of support vector machines" by
  H. Xu, et al., (Journal of Machine Learning Research, vol. 10, pp. 1485-1510,
  2009, arXiv:0803.3490)

abstract:
  This paper comments on the published work dealing with robustness and
regularization of support vector machines (Journal of Machine Learning
Research, vol. 10, pp. 1485-1510, 2009) [arXiv:0803.3490] by H. Xu, etc. They
proposed a theorem to show that it is possible to relate robustness in the
feature space and robustness in the sample space directly. In this paper, we
propose a counter example that rejects their theorem.


title: Frequency of Close Companions among Kepler Planets - a TTV study

abstract:
  A transiting planet exhibits sinusoidal transit-time-variations (TTVs) if
perturbed by a companion near a mean-motion-resonance (MMR). We search for
sinusoidal TTVs in more than 2600 Kepler candidates, using the publicly
available Kepler light-curves (Q0-Q12). We find that the TTV fractions rise
strikingly with the transit multiplicity. Systems where four or more planets
transit enjoy roughly five times higher TTV fraction than those where a single
planet transits, and about twice higher than those for doubles and triples. In
contrast, models in which all transiting planets arise from similar dynamical
configurations predict comparable TTV fractions among these different systems.
One simple explanation for our results is that there are at least two different
classes of Kepler systems, one closely packed and one more sparsely populated.


title: The impact of binary stars on the colors of high-redshift galaxies

abstract:
  Evolutionary population synthesis (EPS) models play an important role in many
studies on the formation and evolution of galaxies. Most EPS models are still
poorly calibrated for certain stellar evolution stages, especially for the
treatment of binary stars, which are very different from single stars. We aim
to present color-magnitude (C-M) and color-color (C-C) relations for passive
model galaxies in the redshift z$\sim0.0-3.0$ and to study the effect of binary
interactions on these relations for high-redshift passive galaxies. Assuming
exponentially declining star formation rate, we used a set of theoretical
galaxy templates obtained from Yunnan EPS models (with and without binary
interactions) to present the C-M and C-C relations for passive galaxies via
Monte Carlo simulation. In Yunnan EPS models with binary interactions, various
processes are included, such as mass transfer, mass accretion, common-envelope
evolution, collisions, supernova kicks, tidal evolution, and all angular
momentum loss mechanisms. In these models, approximately 50 per cent of the
stellar systems are binary systems with orbital periods less than 100\,yr. This
fraction is a typical value for the Milky Way. We find that the inclusion of
binary interactions in the model galaxies' spectra can dramatically alter the
predicted C-M and C-C relations and their evolution with redshift. For $z\sim
0.0$ and $1.0$, the binary interactions have a minor effect on the C-M and C-C
relations, but at $z\sim 2.0$ and $3.0$ the binary interactions have a major
effect on the C-M and C-C relations. Especially for the redshift $z\sim 2.0$,
the $g-$band magnitude becomes smaller by $1.5$\,mag, the $g-r$ color becomes
bluer by $1.0$\,mag, and the $u-g$ color becomes redder by $1.0$\,mag when
binary interactions are included.


title:
Discretizing Distributions with Exact Moments: Error Estimate and
  Convergence Analysis

abstract:
  The maximum entropy principle is a powerful tool for solving underdetermined
inverse problems. This paper considers the problem of discretizing a continuous
distribution, which arises in various applied fields. We obtain the
approximating distribution by minimizing the Kullback-Leibler information
(relative entropy) of the unknown discrete distribution relative to an initial
discretization based on a quadrature formula subject to some moment
constraints. We study the theoretical error bound and the convergence of this
approximation method as the number of discrete points increases. We prove that
(i) the theoretical error bound of the approximate expectation of any bounded
continuous function has at most the same order as the quadrature formula we
start with, and (ii) the approximate discrete distribution weakly converges to
the given continuous distribution. Moreover, we present some numerical examples
that show the advantage of the method and apply to numerically solving an
optimal portfolio problem.


title: Discriminators of quadratic polynomials

abstract:
  Given $f \in \mathbb{Z}[x]$ and $n \in \mathbb{Z^{+}}$, the
$\emph{discriminator}$ $D_f(n)$ is the smallest positive integer $m$ such that
$f(1), \ldots, f(n)$ are distinct mod $m$. In a recent paper, Z.-W. Sun proved
that $D_f(n) = d^{\lceil \log_d n \rceil}$ if $f(x) = x(dx - 1)$ for $d \in
\{2, 3\}$. We extend this result to $d = 2^r$ for any $r \in \mathbb{Z}^{+}$
and find that $D_f(n) = 2^{\lceil \log_2 n \rceil}$ in this case. We also
provide more general statements for $d = p^r$, where $p$ is a prime. In
addition, we present a potential method for generating prime numbers with
discriminators of polynomials which do not always take prime values. Finally,
we describe some general statements and possible topics for study about the
discriminator of an arbitrary polynomial with integer coefficients.


title: Mean quantum percolation

abstract:
  We study the spectrum of adjacency matrices of random graphs. We develop two
techniques to lower bound the mass of the continuous part of the spectral
measure or the density of states. As an application, we prove that the spectral
measure of bond percolation in the two dimensional lattice contains a
non-trivial continuous part in the supercritical regime. The same result holds
for the limiting spectral measure of a supercritical Erdos-Renyi graph and for
the spectral measure of a unimodular random tree with at least two ends. We
give examples of random graphs with purely continuous spectrum.


title:
Characterization and asymptotic analysis of the stationary probabilities
  in Discriminatory Processor Sharing Systems

abstract:
  In this paper, we establish two different results. The first result is a
characterization theorem saying that if the stationary state probabilities for
originally described Markovian discriminatory processor sharing (DPS) system
have a closed product geometric form (the exact definition is given in the
paper), then the system must only be Egalitarian, i.e. all flows in this system
must have equal priorities. The second result is the tail asymptotics for the
stationary probabilities. We provide a detailed asymptotic analysis of the
system, and obtain the exact asymptotic form of the stationary probabilities in
DPS systems when the number of flows in the system is large.


title:
Quark-Gluon plasma fireball evolution with one loop correction in the
  peshier potential

abstract:
  The study of free energy evolution of quark-gluon plasma (QGP) with one loop
correction factor in the peshier potential is discussed. The energy evolution
with the effect of the correction factor in peshier potential shows the
transition temperature obtained in the range of temperature~$T=180-250~MeV$.
  The transition temperature is also effected with the decrease of dynamical
flow parameter of quark and gluon used in the potential and it shows the
observable QGP droplets of the stable size of fermi radius viz $2.5-4.5 fm$.