title: A Time Resolved Study of the Broad Line Region in Blazar 3C 454.3

abstract:
  We present multi-epoch optical observations of the blazar 3C 454.3 (z =
0.859) from 2008 August through 2011 December, using the SMARTS Consortium
1.5m+RCSpectrograph and 1.3m+ANDICAM in Cerro Tololo, Chile. The spectra reveal
that the broad optical emission lines Mg II, H-beta and H-gamma are far less
variable than the optical or gamma-ray continuum. Although, the gamma-rays
varied by a factor of 100 above the EGRET era flux, the lines generally vary by
a factor of 2 or less. Smaller variations in the gamma-ray flux did not produce
significant variation in any of the observed emission lines. Therefore, to
first order, the ionizing flux from the disk changes only slowly during large
variations of the jet. However, two exceptions in the response of the broad
emission lines are reported during the largest gamma-ray flares in 2009
December and 2010 November, when significant deviations from the mean line flux
in H-gamma and Mg II were observed. H-gamma showed a maximum 3-sigma and
4-sigma deviation in each flare, respectively, corresponding to a factor of 1.7
and 2.5 increase in flux. Mg II showed a 2-sigma deviation in both flares; no
variation was detected in H-beta during either flare. These significant
deviations from the mean line flux also coincide with 7mm core ejections
reported previously (Jorstad et al. 2012). The correlation of the increased
emission line flux with mm core ejections, and gamma-ray, optical and UV flares
suggests that the broad line region extends beyond the gamma-emitting region
during the 2009 and 2010 flares.


title: (0,2) Trialities

abstract:
  Motivated by the connection between 4-manifolds and 2d N=(0,2) theories, we
study the dynamics of a fairly large class of 2d N=(0,2) gauge theories. We see
that physics of such theories is very rich, much as the physics of 4d N=1
theories. We discover a new type of duality that is very reminiscent of the 4d
Seiberg duality. Surprisingly, the new 2d duality is an operation of order
three: it is IR equivalence of three different theories and, as such, is
actually a triality. We also consider quiver theories and study their triality
webs. Given a quiver graph, we find that supersymmetry is dynamically broken
unless the ranks of the gauge groups and flavor groups satisfy stringent
inequalities. In fact, for most of the graphs these inequalities have no
solutions. This supports the folklore theorem that generic 2d N=(0,2) theories
break supersymmetry dynamically.


title: Conformal gravity holography in four dimensions

abstract:
  We formulate four-dimensional conformal gravity with (Anti-)de Sitter
boundary conditions that are weaker than Starobinsky boundary conditions,
allowing for an asymptotically subleading Rindler term concurrent with a recent
model for gravity at large distances. We prove the consistency of the
variational principle and derive the holographic response functions. One of
them is the conformal gravity version of the Brown-York stress tensor, the
other is a `partially massless response'. The on-shell action and response
functions are finite and do not require holographic renormalization. Finally,
we discuss phenomenologically interesting examples, including the most general
spherically symmetric solutions and rotating black hole solutions with
partially massless hair.


title:
Effects of the imaginary inflaton component in supergravity new
  inflation

abstract:
  When models of new inflation are implemented in supergravity, the inflaton is
a complex and not a real scalar field. As a complex scalar field has two
independent components, supergravity models of new inflation are naturally
two-field models. In this paper, we use the delta N formalism to analyse how
the two-field behaviour modifies the usual single-field predictions. We find
that the model reduces to the single-field limit if the inflaton mass term is
sufficiently small. Otherwise, the imaginary inflaton component reduces the
amplitude A_s and the spectral index n_s of the scalar curvature perturbations.
However, the perturbations remain nearly Gaussian, and the reduced bispectrum
f_NL is too small to be observed.


title: A Wide-field Near- and Mid-Infrared Census of Young Stars in NGC 6334

abstract:
  This paper presents a study of the rate and efficiency of star formation in
the NGC 6334 star forming region. We obtained observations at J, H, and Ks
taken with the NOAO Extremely Wide-Field Infrared Imager (NEWFIRM) and combined
them with observations taken with the Infrared Array Camera (IRAC) camera on
the Spitzer Space Telescope at wavelengths {\lambda} = 3.6, 4.5, 5.8, and 8.0
{\mu}m. We also analyzed previous observations taken at 24 {\mu}m using the
Spitzer MIPS camera as part of the MIPSGAL survey. We have produced a point
source catalog with >700,000 entries. We have identified 2283 YSO candidates,
375 Class I YSOs and 1908 Class II YSOs using a combination of existing
IRAC-based color classification schemes that we have extended and validated to
the near-IR for use with warm Spitzer data. We have identified multiple new
sites of ongoing star formation activity along filamentary structures extending
tens of parsecs beyond the central molecular ridge of NGC 6334. By mapping the
extinction we derived an estimate for the gas mass, 2.2 x 10^5 M_sun. The heavy
concentration of protostars along the dense filamentary structures indicates
that NGC 6334 may be undergoing a "mini-starburst" event with {\Sigma}{SFR}>8.2
M_sun Myr^-1 pc^-2 and SFE>0.10. We have used these estimates to place NGC 6334
in the Kennicutt-Schmidt diagram to help bridge the gap between observations of
local low-mass star forming regions and star formation in other galaxies.


title:
Hard X-ray Lags in Active Galactic Nuclei: Testing the Distant
  Reverberation Hypothesis with NGC 6814

abstract:
  We present an X-ray spectral and temporal analysis of the variable active
galaxy NGC 6814, observed with Suzaku during November 2011. Remarkably, the
X-ray spectrum shows no evidence for the soft excess commonly observed amongst
other active galaxies, despite its relatively low level of obscuration, and is
dominated across the whole Suzaku bandpass by the intrinsic powerlaw-like
continuum. Despite this, we clearly detect the presence of a low frequency hard
lag of ~1600s between the 0.5-2.0 and 2.0-5.0 keV energy bands at greater than
6-sigma significance, similar to those reported in the literature for a variety
of other AGN. At these energies, any additional emission from e.g. a very weak,
undetected soft excess, or from distant reflection must contribute less than 3%
of the observed countrates (at 90% confidence). Given the lack of any
significant continuum emission component other than the powerlaw, we can rule
out models that invoke distant reprocessing for the observed lag behavior,
which must instead be associated with this continuum emission. These results
are fully consistent with a propagating fluctuation origin for the low
frequency hard lags, and with the interpretation of the high frequency soft
lags - a common feature seen in the highest quality AGN data with strong soft
excesses - as reverberation from the inner accretion disk.


title: Solar axion flux from the axion-electron coupling

abstract:
  In non-hadronic axion models, where axions couple to electrons at tree level,
the solar axion flux is completely dominated by the ABC reactions (Atomic
recombination and deexcitation, Bremsstrahlung and Compton). In this paper the
ABC flux is computed from available libraries of monochromatic photon radiative
opacities (OP, LEDCOP and OPAS) by exploiting the relations between axion and
photon emission cross sections. These results turn to be ~ 30% larger than
previous estimates due to atomic recombination (free-bound electron
transitions) and deexcitation (bound-bound), which where not previously taken
into account.


title: The Formation History of the Ultra-Faint Dwarf Galaxies

abstract:
  We present early results from a Hubble Space Telescope survey of the
ultra-faint dwarf galaxies. These Milky Way satellites were discovered in the
Sloan Digital Sky Survey, and appear to be an extension of the classical dwarf
spheroidals to low luminosities, offering a new front in the efforts to
understand the missing satellite problem. Because they are the least luminous,
most dark matter dominated, and least chemically evolved galaxies known, the
ultra-faint dwarfs are the best candidate fossils from the early universe. The
primary goal of the survey is to measure the star-formation histories of these
galaxies and discern any synchronization due to the reionization of the
universe. We find that the six galaxies of our survey have very similar
star-formation histories, and that each is dominated by stars older than 12
Gyr.


title: Subhaloes gone Notts: the clustering properties of subhaloes

abstract:
  We present a study of the substructure finder dependence of subhalo
clustering in the Aquarius Simulation. We run 11 different subhalo finders on
the haloes of the Aquarius Simulation and we study their differences in the
density profile, mass fraction and 2-point correlation function of subhaloes in
haloes. We also study the mass and vmax dependence of subhalo clustering. As
the Aquarius Simulation has been run at different resolutions, we study the
convergence with higher resolutions. We find that the agreement between finders
is at around the 10% level inside R200 and at intermediate resolutions when a
mass threshold is applied, and better than 5% when vmax is restricted instead
of mass. However, some discrepancies appear in the highest resolution,
underlined by an observed resolution dependence of subhalo clustering. This
dependence is stronger for the smallest subhaloes, which are more clustered in
the highest resolution, due to the detection of subhaloes within subhaloes (the
sub-subhalo term). This effect modifies the mass dependence of clustering in
the highest resolutions. We discuss implications of our results for models of
subhalo clustering and their relation with galaxy clustering.


title:
Anomalous Thermomechanical Properties of a Self-propelled Colloidal
  Fluid

abstract:
  We use numerical simulations to compute the equation of state of a suspension
of spherical, self-propelled nanoparticles. We study in detail the effect of
excluded volume interactions and confinement as a function of the system
temperature, concentration and strength of the propulsion. We find a striking
non-monotonic dependence of the pressure with the temperature, and provide
simple scaling arguments to predict and explain the occurrence of such an
anomalous behavior. We conclude the paper by explicitly showing how our results
have an important implications for the effective forces exerted by fluids of
self-propelled particles on passive, larger components.

categories: cond-mat.soft cond-mat.mes-hall cond-mat.mtrl-sci physics.chem-ph


title: N=2 supersymmetric gauge theories and quantum integrable systems

abstract:
  We study N=2 supersymmetric gauge theories on the product of a two-sphere and
a cylinder. We show that the low-energy dynamics of a BPS sector of such a
theory is described by a quantum integrable system, with the Planck constant
set by the inverse of the radius of the sphere. If the sphere is replaced with
a hemisphere, then our system reduces to an integrable system of the type
studied by Nekrasov and Shatashvili. In this case we establish a correspondence
between the effective prepotential of the gauge theory and the Yang-Yang
function of the integrable system.


title:
Dark Matter Constraints from Observations of 25 Milky Way Satellite
  Galaxies with the Fermi Large Area Telescope

abstract:
  The dwarf spheroidal satellite galaxies of the Milky Way are some of the most
dark-matter-dominated objects known. Due to their proximity, high dark matter
content, and lack of astrophysical backgrounds, dwarf spheroidal galaxies are
widely considered to be among the most promising targets for the indirect
detection of dark matter via gamma rays. Here we report on gamma-ray
observations of 25 Milky Way dwarf spheroidal satellite galaxies based on 4
years of Fermi Large Area Telescope (LAT) data. None of the dwarf galaxies are
significantly detected in gamma rays, and we present gamma-ray flux upper
limits between 500 MeV and 500 GeV. We determine the dark matter content of 18
dwarf spheroidal galaxies from stellar kinematic data and combine LAT
observations of 15 dwarf galaxies to constrain the dark matter annihilation
cross section. We set some of the tightest constraints to date on the the
annihilation of dark matter particles with masses between 2 GeV and 10 TeV into
prototypical Standard Model channels. We find these results to be robust
against systematic uncertainties in the LAT instrument performance, diffuse
gamma-ray background modeling, and assumed dark matter density profile.


title:
Entanglement spectra between coupled Tomonaga-Luttinger liquids:
  Applications to ladder systems and topological phases

abstract:
  We study the entanglement spectrum (ES) and entropy between two coupled
Tomonaga-Luttinger liquids (TLLs) on parallel periodic chains. This problem
gives access to the entanglement properties of various interesting systems,
such as spin ladders as well as two-dimensional topological phases. By
expanding interchain interactions to quadratic order in bosonic fields, we are
able to calculate the ES for both gapped and gapless systems using only methods
for free theories. In certain gapless phases of coupled non-chiral TLLs, we
interestingly find an ES with a dispersion relation proportional to the square
root of the subsystem momentum, which we relate to a long-range interaction in
the entanglement Hamiltonian. We numerically demonstrate the emergence of this
unusual dispersion in a model of hard-core bosons on a ladder. In gapped phases
of coupled non-chiral TLLs, which are relevant to spin ladders and topological
insulators, we show that the ES consists of linearly dispersing modes, which
resembles the spectrum of a single-chain TLL but is characterized by a modified
TLL parameter. Based on a calculation for coupled chiral TLLs, we are also able
to provide a very simple proof for the correspondence between the ES and the
edge-state spectrum in quantum Hall systems consistent with previous numerical
and analytical studies.


title:
Diffusion, subdiffusion, and trapping of active particles in
  heterogeneous media

abstract:
  We study the transport properties of a system of active particles moving at
constant speed in an heterogeneous two-dimensional space. The spatial
heterogeneity is modeled by a random distribution of obstacles, which the
active particles avoid. Obstacle avoidance is characterized by the particle
turning speed $\gamma$. We show, through simulations and analytical
calculations, that the mean square displacement of particles exhibits two
regimes as function of the density of obstacles $\rho_o$ and $\gamma$. We find
that at low values of $\gamma$, particle motion is diffusive and characterized
by a diffusion coefficient that displays a minimum at an intermediate obstacle
density $\rho_o$. We observe that in high obstacle density regions and for
large $\gamma$ values, spontaneous trapping of active particles occurs. We show
that such trapping leads to genuine subdiffusive motion of the active
particles. We indicate how these findings can be used to fabricate a filter of
active particles.


title: Patching and the p-adic local Langlands correspondence

abstract:
  We use the patching method of Taylor--Wiles and Kisin to construct a
candidate for the p-adic local Langlands correspondence for GL_n(F), F a finite
extension of Q_p. We use our construction to prove many new cases of the
Breuil--Schneider conjecture.


title:
Robustness of the filamentation instability for asymmetric plasma shells
  collision in arbitrarily oriented magnetic field

abstract:
  The filamentation instability triggered when two counter streaming plasma
shells overlap appears to be the main mechanism by which collisionless shocks
are generated. It has been known for long that a flow aligned magnetic field
can completely suppress this instability. In a recent paper [PHYSICS OF PLASMAS
18, 080706 (2011)], it was demonstrated in two dimensions that for the case of
two cold, symmetric, relativistically colliding shells, such cancellation
cannot occur if the field is not perfectly aligned. Here, this result is
extended to the case of two asymmetric shells. The filamentation instability
appears therefore as an increasingly robust mechanism to generate shocks.


title:
Flips in combinatorial pointed pseudo-triangulations with face degree at
  most four

abstract:
  In this paper we consider the flip operation for combinatorial pointed
pseudo-triangulations where faces have size 3 or 4, so-called combinatorial
4-PPTs. We show that every combinatorial 4-PPT is stretchable to a geometric
pseudo-triangulation, which in general is not the case if faces may have size
larger than 4. Moreover, we prove that the flip graph of combinatorial 4-PPTs
is connected and has diameter $O(n^2)$, even in the case of labeled vertices
with fixed outer face. For this case we provide an $\Omega(n\log n)$ lower
bound.


title: The Herschel/PACS view of disks around low-mass stars in Chamaleon-I

abstract:
  Circumstellar disks are expected to be the birthplaces of planets. The
potential for forming one or more planets of various masses is essentially
driven by the initial mass of the disks. We present and analyze Herschel/PACS
observations of disk-bearing M-type stars that belong to the young ~2 Myr old
Chamaleon-I star forming region. We used the radiative transfer code RADMC to
successfully model the SED of 17 M-type stars detected at PACS wavelengths. We
first discuss the relatively low detection rates of M5 and later spectral type
stars with respect to the PACS sensitivity, and argue their disks masses, or
flaring indices, are likely to be low. For M0 to M3 stars, we find a relatively
broad range of disk masses, scale heights, and flaring indices. Via a
parametrization of dust stratification, we can reproduce the peak fluxes of the
10 $\mu$m emission feature observed with Spitzer/IRS, and find that disks
around M-type stars may display signs of dust sedimentation. The Herschel/PACS
observations of low-mass stars in Cha-I provide new constraints on their disk
properties, overall suggesting that disk parameters for early M-type stars are
comparable to those for more massive stars (e.g., comparable scale height and
flaring angles). However, regions of the disks emitting at about 100 $\mu$m may
still be in the optically thick regime, preventing direct determination of disk
masses. Thus the modeled disk masses should be considered as lower limits.
Still, we are able to extend the wavelength coverage of SED models and start
characterizing effects such as dust sedimentation, an effort leading the way
towards ALMA observations of these low-mass stars.


title: The Discovery of Pulsating Hot Subdwarfs in NGC 2808

abstract:
  We present the results of a Hubble Space Telescope program to search for
pulsating hot subdwarfs in the core of NGC 2808. These observations were
motivated by the recent discovery of such stars in the outskirts of omega Cen.
Both NGC 2808 and omega Cen are massive globular clusters exhibiting complex
stellar populations and large numbers of extreme horizontal branch stars. Our
far-UV photometric monitoring of over 100 hot evolved stars has revealed six
pulsating subdwarfs with periods ranging from 85 to 149 s and UV amplitudes of
2.0 to 6.8%. In the UV color-magnitude diagram of NGC 2808, all six of these
stars lie immediately below the canonical horizontal branch, a region populated
by the subluminous "blue-hook" stars. For three of these six pulsators, we also
have low-resolution far-UV spectroscopy that is sufficient to broadly constrain
their atmospheric abundances and effective temperatures. Curiously, and in
contrast to the omega Cen pulsators, the NGC 2808 pulsators do not exhibit the
spectroscopic or photometric uniformity one might expect from a well-defined
instability strip, although they all fall within a narrow band (0.2 mag) of
far-UV luminosity.


title:
X-ray Surface Brightness Profiles of Active Galactic Nuclei in the
  Extended Groth Strip: Implications for AGN Feedback

abstract:
  Using data from the All Wavelength Extended Groth Strip International Survey
(AEGIS) we statistically detect the extended X-ray emission in the interstellar
medium (ISM)/intra-cluster medium (ICM) in both active and normal galaxies at
0.3 <= z <= 1.3. For both active galactic nuclei (AGN) host galaxy and normal
galaxy samples that are matched in restframe color, luminosity, and redshift
distribution, we tentatively detect excess X-ray emission at scales of 1--10
arcsec at a few sigma significance in the surface brightness profiles. The
exact significance of this detection is sensitive to the true characterization
of Chandra's point spread function. The observed excess in the surface
brightness profiles is suggestive of lower extended emission in AGN hosts
compared to normal galaxies. This is qualitatively similar to theoretical
predictions of the X-ray surface brightness profile from AGN feedback models,
where feedback from AGN is likely to evacuate the gas from the center of the
galaxy/cluster. We propose that AGN that are intrinsically under-luminous in
X-rays, but have equivalent bolometric luminosities to our sources will be the
ideal sample to study more robustly the effect of AGN feedback on diffuse
ISM/ICM gas.


title: Lifshitz black holes in higher spin gravity

abstract:
  We study asymptotically Lifshitz solutions to three dimensional higher spin
gravity in the SL(3,R)xSL(3,R) Chern-Simons formulation. We begin by specifying
the most general connections satisfying Lifshitz boundary conditions, and we
verify that their algebra of symmetries contains a Lifshitz sub-algebra. We
then exhibit connections that can be viewed as higher spin Lifshitz black
holes. We show that when suitable holonomy conditions are imposed, these black
holes obey sensible thermodynamics and possess a gauge in which the
corresponding metric exhibits a regular horizon.


title: Order polynomials and P\'olya's enumeration theorem

abstract:
  P\'olya's enumeration theorem is concerned with counting labeled sets up to
symmetry. Given a finite group acting on a finite set of labeled elements it
states that the number of labeled sets up to symmetry is given by a polynomial
in the number of labels. We give a new perspective on this theorem by
generalizing it to partially ordered sets and order preserving maps. Further we
prove a reciprocity statement in terms of strictly order preserving maps
generalizing a classical result by Stanley (1970). We apply our results to
counting graph colorings up to symmetry.


title:
Period-luminosity relations in evolved red giants explained by
  solar-like oscillations

abstract:
  Solar-like oscillations in red giants have been investigated with CoRoT and
Kepler, while pulsations in more evolved M giants have been studied with
ground-based microlensing surveys. After 3.1 years of observation with Kepler,
it is now possible to make a link between these different observations of
semi-regular variables. We aim to identify period-luminosity sequences in
evolved red giants identified as semi-regular variables. Then, we investigate
the consequences of the comparison of ground-based and space-borne
observations. We have first measured global oscillation parameters of evolved
red giants observed with Kepler with the envelope autocorrelation function
method. We then used an extended form of the universal red giant oscillation
pattern, extrapolated to very low frequency, to fully identify their
oscillations. From the link between red giant oscillations observed by Kepler
and period-luminosity sequences, we have identified these relations in evolved
red giants as radial and non-radial solar-like oscillations. We were able to
expand scaling relations at very low frequency. This helped us to identify the
different sequences of period-luminosity relations, and allowed us to propose a
calibration of the K magnitude with the observed frequency large separation.
Interpreting period-luminosity relations in red giants in terms of solar-like
oscillations allows us to investigate, with a firm physical basis, the time
series obtained from ground-based microlensing surveys. This can be done with
an analytical expression that describes the low-frequency oscillation spectra.
The different behavior of oscillations at low frequency, with frequency
separations scaling only approximately with the square root of the mean stellar
density, can be used to address precisely the physics of the semi-regular
variables.


title:
Weak Scale Baryogenesis in a Supersymmetric Scenario with R-parity
  violation

abstract:
  We investigate the connection between R-parity violation (RPV) in
supersymmetric models and Baryogenesis. First we discuss in detail the
assumptions of a theorem by Nanopoulos and Weinberg on the CP asymmetry
generated from the decay of massive particles. In light of this statement, we
analyse some interesting models of Baryogenesis through RPV. We then explore,
in the context of RPV SUSY, the possibility to generate the baryon asymmetry
through the out-of-equilibrium decay of a metastable Weakly Interacting Massive
Particle (WIMP), as proposed in \cite{Cui:2012jh}. This setting is also
motivated by the observed coincidence between the abundances of dark and
baryonic matter. In this framework, we propose two models of out-of-equilibrium
decay of a would-be cold relic, and compute the associated CP asymmetry. With a
TeV-scale parent, the observed baryon abundance can be reproduced in these
models when the stop is in the multi-TeV region. Furthermore, annihilation of
the metastable particle into SM states must be characterised by a very weak
coupling, $g\sim 10^{-2}$ and by a heavy mediator $m_{med}\sim 10$ TeV. These
models can also accommodate stop masses far from the TeV scale, at the expense
of weakening the explanation of the $\Omega_{B}-\Omega_{DM}$ coincidence.


title: Real relativistic fluids in heavy ion collisions

abstract:
  The theory of real relativistic fluids is in the rather unique situation that
there is a natural relativistic extension of the nonrelativistic theory, but it
is physically untenable. On the other hand, mounting evidence that matter
created in relativistic heavy ion collisions behaves as a relativistic fluid
with small but finite viscosity has given the quest for an alternative a
definite goal. We shall review different approaches to relativistic real
fluids, their link to relativistic kinetic theory, and their application to the
analysis of heavy ion collisions


title: Essential lack of security proof in quantum key distribution

abstract:
  All the currently available unconditional security proofs on quantum key
distribution, in particular for the BB84 protocol and its variants including
continuous-variable ones, are invalid or incomplete at many points. In this
paper we discuss some of the main known problems, particularly those on
operational security guarantee and error correction. Most basic are the points
that there is no security parameter in such protocols and it is not the case
the generated key is perfect with probability $\geq 1-\epsilon$ under the trace
distance criterion $d\leq\epsilon$, which is widely claimed in the technical
and popular literature. The many serious security consequences of this error
about the QKD generated key would be explained, including practical
ramification on achievable security levels. It will be shown how the error
correction problem alone may already defy rigorous quantitative analysis.
Various other problems would be touched upon. It is pointed out that rigorous
security guarantee of much more efficient quantum cryptosystems may be obtained
by abandoning the disturbance-information tradeoff principle and utilizing
instead the known KCQ (keyed communication in quantum noise) principle in
conjunction with a new DBM (decoy bits method) principle that will be detailed
elsewhere.


title: Polygonal VH Complexes

abstract:
  Ian Leary inquires whether a class of hyperbolic finitely presented groups
are residually finite. We answer in the affirmative by giving a systematic
version of a construction in his paper, which shows that the standard
2-complexes of these presentations have a VH-structure. This structure induces
a splitting of these groups, which together with hyperbolicity, implies that
these groups are residually finite.


title: The Quillen category of finite p-groups and coclass theory

abstract:
  Coclass theory can be used to define infinite families of finite p-groups of
a fixed coclass. It is conjectured that the groups in one of these infinite
families all have isomorphic mod-p cohomology rings. Here we prove that almost
all groups in one of these infinite families have equivalent Quillen
categories. We also show how the Quillen categories of the groups in an
infinite family are connected to the Quillen category of their associated
infinite pro-p-group of finite coclass.


title:
The New Resonating Valence Bond Method for Ab-Initio Electronic
  Simulations

abstract:
  The Resonating Valence Bond theory of the chemical bond was introduced soon
after the discovery of quantum mechanics and has contributed to explain the
role of electron correlation within a particularly simple and intuitive
approach where the chemical bond between two nearby atoms is described by one
or more singlet electron pairs. In this chapter Pauling's resonating valence
bond theory of the chemical bond is revisited within a new formulation,
introduced by P.W. Anderson after the discovery of High-Tc superconductivity.
It is shown that this intuitive picture of electron correlation becomes now
practical and efficient, since it allows us to faithfully exploit the locality
of the electron correlation, and to describe several new phases of matter, such
as Mott insulators, High-Tc superconductors, and spin liquid phases.

categories: physics.comp-ph cond-mat.str-el cond-mat.supr-con physics.chem-ph quant-ph


title:
Stationary entanglement entropies following an interaction quench in 1D
  Bose gas

abstract:
  We analyze the entanglement properties of the asymptotic steady state after a
quench from free to hard-core bosons in one dimension. The R\'enyi and von
Neumann entanglement entropies are found to be extensive, and the latter
coincides with the thermodynamic entropy of the Generalized Gibbs Ensemble
(GGE). Computing the spectrum of the two-point function, we provide exact
analytical results both for the leading extensive parts and the subleading
terms for the entropies as well as for the cumulants of the particle number
fluctuations. We also compare the extensive part of the entanglement entropy
with the thermodynamic ones, showing that the GGE entropy equal the
entanglement one and it is the double of the diagonal entropy.


title:
Non-Parametric Weighted Tests for Independence Based on Empirical Copula
  Process

abstract:
  We propose a class of flexible non-parametric tests for the presence of
dependence between components of a random vector based on weighted
Cram\'{e}r-von Mises functionals of the empirical copula process. The weights
act as a tuning parameter and are shown to significantly influence the power of
the test, making it more sensitive to different types of dependence. Asymptotic
properties of the test are stated in the general case, for an arbitrary bounded
and integrable weighting function, and computational formulas for a number of
weighted statistics are provided. Several issues relating to the choice of the
weights are discussed, and a simulation study is conducted to investigate the
power of the test under a variety of dependence alternatives. The greatest gain
in power is found to occur when weights are set proportional to true deviations
from independence copula.


title: Weyl Curvature, Del Pezzo Surfaces, and Almost-Kaehler Geometry

abstract:
  If a smooth compact 4-manifold M admits a Kaehler-Einstein metric g of
positive scalar curvature, Gursky showed that its conformal class [g] is an
absolute minimizer of the Weyl functional among all conformal classes with
positive Yamabe constant. Here we prove that, with the same hypotheses, [g]
also minimizes of the Weyl functional on a different open set of conformal
classes, most of which have negative Yamabe constant. An analogous minimization
result is then proved for Einstein metrics g which are Hermitian, but not
Kaehler.


title: Photoluminescence in array of doped semiconductor nanocrystals

abstract:
  We study the dependence of the quantum yield of photoluminescence of a dense,
periodic array of semiconductor nanocrystals (NCs) on the level of doping and
NC size. Electrons introduced to NCs via doping quench photoluminescence by the
Auger process, so that practically only NCs without electrons contribute to the
photoluminescence. Computer simulation and analytical theory are used to find a
fraction of such empty NCs as a function of the average number of donors per NC
and NC size. For an array of small spherical NCs, the quantization gap between
1S and 1P levels leads to transfer of electrons from NCs with large number of
donors to those without donors. As a result, empty NCs become extinct, and
photoluminescence is quenched abruptly at an average number of donors per NC
close to 1.8. The relative intensity of photoluminescence is shown to correlate
with the type of hopping conductivity of an array of NCs.


title: A survey on the Convergence of Manifolds with Boundary

abstract:
  This survey reviews precompactness theorems for classes of Riemannian
manifolds with boundary. We begin with the works of Kodani,
Anderson-Katsuda-Kurylev-Lassas-Taylor and Wong. We then present new results of
Knox and the author with Sormani.


title: A generalization of Aztec diamond theorem, part I

abstract:
  We generalize Aztec diamond theorem (N. Elkies, G. Kuperberg, M. Larsen, and
J. Propp, Alternating-sign matrices and domino tilings, Journal Algebraic
Combinatoric, 1992) by showing that the numbers of tilings of a certain family
of regions in the square lattice with southwest-to-northeast diagonals drawn in
are given by powers of 2. We present a proof for the generalization by using a
bijection between domino tilings and non-intersecting lattice paths.


title: Hom Quandles

abstract:
  If $A$ is an abelian quandle and $Q$ is a quandle, the hom set
$\mathrm{Hom}(Q,A)$ of quandle homomorphisms from $Q$ to $A$ has a natural
quandle structure. We exploit this fact to enhance the quandle counting
invariant, providing an example of links with the same counting invariant
values but distinguished by the hom quandle structure. We generalize the result
to the case of biquandles, collect observations and results about abelian
quandles and the hom quandle, and show that the category of abelian quandles is
symmetric monoidal closed.


title: Magnetic Field Amplification in Young Galaxies

abstract:
  The Universe at present is highly magnetized, with fields of the order of a
few 10^-5 G and coherence lengths larger than 10 kpc in typical galaxies like
the Milky Way. We propose that the magnetic field was amplified to this values
already during the formation and the early evolution of the galaxies.
Turbulence in young galaxies is driven by accretion as well as by supernova
(SN) explosions of the first generation of stars. The small-scale dynamo can
convert the turbulent kinetic energy into magnetic energy and amplify very weak
primordial magnetic seed fields on short timescales. The amplification takes
place in two phases: in the kinematic phase the magnetic field grows
exponentially, with the largest growth on the smallest non-resistive scale. In
the following non-linear phase the magnetic energy is shifted towards larger
scales until the dynamo saturates on the turbulent forcing scale. To describe
the amplification of the magnetic field quantitatively we model the
microphysics in the interstellar medium (ISM) of young galaxies and determine
the growth rate of the small-scale dynamo. We estimate the resulting saturation
field strengths and dynamo timescales for two turbulent forcing mechanisms:
accretion-driven turbulence and SN-driven turbulence. We compare them to the
field strength that is reached, when only stellar magnetic fields are
distributed by SN explosions. We find that the small-scale dynamo is much more
efficient in magnetizing the ISM of young galaxies. In the case of
accretion-driven turbulence a magnetic field strength of the order of 10^-6 G
is reached after a time of 24-270 Myr, while in SN-driven turbulence the dynamo
saturates at field strengths of typically 10^-5 G after only 4-15 Myr. This is
considerably shorter than the Hubble time. Our work can help to understand why
present-day galaxies are highly magnetized.

categories: astro-ph.GA astro-ph.CO physics.flu-dyn physics.plasm-ph physics.space-ph


title:
Skyrme functional from a three-body pseudo-potential of second-order in
  gradients. Formalism for central terms

abstract:
  In one way or the other, all modern parametrizations of the nuclear energy
density functional (EDF) do not respect the exchange symmetry associated with
Pauli's principle. It has been recently shown that this practice jeopardizes
multi-reference (MR) EDF calculations by contaminating the energy with spurious
self-interactions that, for example, lead to finite steps or even divergences
when plotting it as a function of collective coordinates. As of today, the only
viable option to bypass these pathologies is to rely on EDF kernels that
enforce Pauli's principle from the outset by strictly and exactly deriving from
a genuine, i.e. density-independent, Hamilton operator.
  We wish to develop the most general Skyrme-like EDF parametrization
containing linear, bilinear and trilinear terms in the density matrices with up
to two gradients, under the key constraint that it derives strictly from an
effective Hamilton operator. The most general three-body Skyrme-like
pseudo-potential containing up to two gradient operators is constructed to
generate the trilinear part. The present study is limited to central terms.
Spin-orbit and tensor will be addressed in a forthcoming paper.
  (See paper for full abstract)


title: Charmless three-body decays of b-hadrons

abstract:
  A review of recent results from LHCb and the B-factories on the charmless
decays of b-hadrons into three-body final states is presented.


title: Proton structure and tensor gluons

abstract:
  We consider a possibility that inside the proton and, more generally, inside
the hadrons there are additional partons - tensor-gluons, which can carry a
part of the proton momentum. The tensor-gluons have zero electric charge, like
gluons, but have a larger spin. Inside the proton a nonzero density of the
tensor-gluons can be generated by the emission of tensor-gluons by gluons. The
last mechanism is typical for non-Abelian tensor gauge theories, in which there
exists a gluon-tensor-tensor vertex of order g. Therefore the number of gluons
changes not only because a quark may radiate a gluon or because a gluon may
split into a quark-antiquark pair or into two gluons, but also because a gluon
can split into two tensor-gluons. The process of gluon splitting suggests that
part of the proton momentum which was carried by neutral partons is shared
between vector and tensor gluons. We derive evolution equations for the parton
distribution functions which take into account these new processes. The
momentum sum rule allows to find the tensor-gluons contribution to the
Callan-Simanzik beta function and to calculate the corresponding anomalous
dimensions. This contribution changes the behavior of the structure functions,
and the logarithmic correction to the Bjorken scaling becomes more mild. This
also influences the unification scale at which the coupling constants of the
Standard Model merge, shifting its value to lower energies of order of 40 TeV.


title:
Measurements and Kernels for Source-Structure Inversions in Noise
  Tomography

abstract:
  Seismic noise cross correlations are used to image crustal structure and
heterogeneity. Typically, seismic networks are only anisotropically illuminated
by seismic noise, a consequence of the non-uniform distribution of sources.
Here, we study the sensitivity of such a seismic network to structural
heterogeneity in a 2-D setting. We compute finite-frequency cross-correlation
sensitivity kernels for travel-time, waveform-energy and waveform-difference
measurements. In line with expectation, wavespeed anomalies are best imaged
using travel times and the source distribution using cross-correlation
energies. Perturbations in attenuation and impedance are very difficult to
image and reliable inferences require a high degree of certainty in the
knowledge of the source distribution and wavespeed model (at least in the case
of transmission tomography studied here). We perform single-step Gauss-Newton
inversions for the source distribution and the wavespeed, in that order, and
quantify the associated Cram\'{e}r-Rao lower bound. The inversion and
uncertainty estimate are robust to errors in the source model but are sensitive
to the theory used to interpret of measurements. We find that when classical
source-receiver kernels are used instead of cross-correlation kernels, errors
appear in the both the inversion and uncertainty estimate, systematically
biasing the results. We outline a computationally tractable algorithm to
account for distant sources when performing inversions.


title: Holographic RG flows and nearly-marginal operators

abstract:
  The holographic renormalization group flows associated with marginally
relevant operators are analyzed. The associated perturbative and
non-perturbative beta-functions are calculated and the consistent scalar
potentials are identified. The presence of a Zamolodchikov metric in the
multiscalar case is shown to affect beta-functions starting at two loops.


title:
The formation of massive black holes in z~30 dark matter haloes with
  large baryonic streaming velocities

abstract:
  The origins of the ~10^9 Msun quasar supermassive black holes (BHs) at
redshifts z > 6 remain a theoretical puzzle. One possibility is that they grew
from ~10^5 Msun BHs formed in the 'direct collapse' of pristine, atomic-cooling
(temperatures T ~ 8000 K; PAC) gas that did not fragment to form ordinary stars
due to a lack of molecular hydrogen and metals. We propose that baryonic
streaming---the relic relative motion of gas with respect to dark matter from
cosmological recombination---provides a natural mechanism for establishing the
conditions necessary for direct collapse. This effect delays the formation of
the first stars by inhibiting the infall of gas into dark matter haloes;
streaming velocities more than twice the root-mean-square value could forestall
star formation until halo virial temperatures Tvir ~ 8000 K. The resulting PAC
gas can proceed to form massive BHs by any of the mechanisms proposed in the
literature to induce direct collapse in the absence of a ultraviolet
background. This scenario produces haloes containing PAC gas at a
characteristic redshift z ~ 30. It can explain the abundance of the most
luminous quasars at z = 6, regardless of whether direct collapse occurs in
nearly all or less than 1 per cent of PAC haloes.


title:
Connected sum construction of constant Q-curvature manifolds in higher
  dimensions

abstract:
  For a compact Riemannian manifold $(M, g_2)$ with constant $Q$-curvature of
dimension $n\geq 6$ satisfying nondegeneracy condition, we show that one can
construct many examples of constant $Q$-curvature manifolds by gluing
construction. We provide a general procedure of gluing together $(M,g_2)$ with
any compact manifold $(N, g_1)$ satisfying a geometric assumption. In
particular, we can prove that there exists a metric with constant $Q$-curvature
on the connected sum $N #M$.


title: Assessment of the 2880 impact threat from asteroid (29075) 1950 DA

abstract:
  In this paper we perform an assessment of the 2880 Earth impact risk for
asteroid (29075) 1950 DA. To obtain reliable predictions we analyze the
contribution of the observational dataset and the astrometric treatment, the
numerical error in the long-term integration, and the different accelerations
acting on the asteroid. The main source of uncertainty is the Yarkovsky effect,
which we statistically model starting from 1950 DA's available physical
characterization, astrometry, and dynamical properties. Before the release of
2012 radar data, this modeling suggests that 1950 DA has 99% likelihood of
being a retrograde rotator. By using a 7-dimensional Monte Carlo sampling we
map 1950 DA's uncertainty region to the 2880 close approach b-plane and find a
5 x 10^-4 impact probability. With the recently released 2012 radar
observations, the direct rotation is definitely ruled out and the impact
probability decreases to 2.5 x 10^-4.


title:
Relating $D^* \bar{D}^*$ currents with $J^\pi= 0^+,1^+$ and $2^+$ to
  $Z_c$ states

abstract:
  In this work we study the $D^* \bar{D}^*$ current with QCD sum rules. We
write the correlation function using the general current corresponding to the
$D^* \bar{D}^*$ system and then use spin projectors to obtain the correlation
function in the $0^+, 1^+$ and $2^+$ spin-parity configurations. The purpose of
the present work is to investigate the possibility of explaining the recently
reported $Z_c(4025)$ as a $D^* \bar{D}^*$ moleculelike state. As a result we
find a state for each spin case with a very similar mass: $M^{S=0} = \left(3943
\pm 104\right)$ MeV, $M^{S=1} = \left(3950 \pm 105\right)$ MeV, $M^{S=2} =
\left(3946 \pm 104 \right)$ MeV. We discuss that our mass results, within error
bars, for $1^+$ or $2^+$ are both compatible with $Z_c(4025)$. However, our
results are also compatible with a possible $D^* \bar{D}^*$ bound state, in
agreement with predictions of some previous works. We have also calculated the
current-state coupling which turns out to be larger in the $2^+$ case.


title: Optimal complexity correction of correlated errors in the surface code

abstract:
  The surface code is designed to suppress errors in quantum computing hardware
and currently offers the most believable pathway to large-scale quantum
computation. The surface code requires a 2-D array of nearest-neighbor coupled
qubits that are capable of implementing a universal set of gates with error
rates below approximately 1%, requirements compatible with experimental
reality. Consequently, a number of authors are attempting to squeeze additional
performance out of the surface code. We describe an optimal complexity error
suppression algorithm, parallelizable to O(1) given constant computing
resources per unit area, and provide evidence that this algorithm exploits
correlations in the error models of each gate in an asymptotically optimal
manner.


title:
Criminal Geographical Profiling: Using FCA for Visualization and
  Analysis of Crime Data

abstract:
  Fighting criminal activities in our modern societies required the engagement
of intelligent information systems that can analyze crime data geographically
and enable new concepts to be deduced from it. These information systems should
be able to create visualization of such data as well as have the capability of
giving new incite of information, if data is updated whilst maintaining the
previously predicted patterns. This paper proposed the use of Formal Concept
Analysis, or Galois Lattices, a data analysis technique grounded on Lattice
Theory and Propositional Calculus, for the visualization and analysis of crime
data. This method considered the set of common and distinct attributes of
crimes in such a way that categorization are done based on related crime types,
geographical locations and the persons involved.


title: Electricity Market Forecasting via Low-Rank Multi-Kernel Learning

abstract:
  The smart grid vision entails advanced information technology and data
analytics to enhance the efficiency, sustainability, and economics of the power
grid infrastructure. Aligned to this end, modern statistical learning tools are
leveraged here for electricity market inference. Day-ahead price forecasting is
cast as a low-rank kernel learning problem. Uniquely exploiting the market
clearing process, congestion patterns are modeled as rank-one components in the
matrix of spatio-temporally varying prices. Through a novel nuclear norm-based
regularization, kernels across pricing nodes and hours can be systematically
selected. Even though market-wide forecasting is beneficial from a learning
perspective, it involves processing high-dimensional market data. The latter
becomes possible after devising a block-coordinate descent algorithm for
solving the non-convex optimization problem involved. The algorithm utilizes
results from block-sparse vector recovery and is guaranteed to converge to a
stationary point. Numerical tests on real data from the Midwest ISO (MISO)
market corroborate the prediction accuracy, computational efficiency, and the
interpretative merits of the developed approach over existing alternatives.


title:
Disaggregated Bundle Methods for Distributed Market Clearing in Power
  Networks

abstract:
  A fast distributed approach is developed for the market clearing with
large-scale demand response in electric power networks. In addition to
conventional supply bids, demand offers from aggregators serving large numbers
of residential smart appliances with different energy constraints are
incorporated. Leveraging the Lagrangian relaxation based dual decomposition,
the resulting optimization problem is decomposed into separate subproblems, and
then solved in a distributed fashion by the market operator and each aggregator
aided by the end-user smart meters. A disaggregated bundle method is adapted
for solving the dual problem with a separable structure. Compared with the
conventional dual update algorithms, the proposed approach exhibits faster
convergence speed, which results in reduced communication overhead. Numerical
results corroborate the effectiveness of the novel approach.


title: Touch-enabled Programming for the Lab of Things

abstract:
  Lab of Things (LoT, lab-of-things.com) is a research platform for
interconnection, programming, and large scale deployment of devices and
sensors. These devices and sensors can then be used for deployment of field
studies in a variety of research areas including elderly care, energy
management, and the like. LoT is built on top of HomeOS, a middle-ware
component, making interconnection of a wide range of devices possible. LoT also
provides cloud storage and remote monitoring capabilities. Traditionally
programming on the LoT platform has been done using C# in Microsoft Visual
Studio. While LoT programs developed on the .NET framework offer a rich set of
functionality, writing programs on LoT can be challenging for developers who
are not experienced with the technology involved. In this demonstration, we
introduce an innovative programming approach on the LoT platform by building a
Generic Application and creating corresponding libraries on the user-friendly
TouchDevelop (touchdevelop.com) programming environment. As an example, we
implemented the same functionality of the Lab of Things Alerts application
using the new Generic App. In addition to a touch-enabled programming
environment, the new approach also significantly saves time and effort
developers have to devote when creating a customized Lab of Things application.


title:
Correlated transport through junction arrays in the small Josephson
  energy limit: incoherent Cooper-pairs and hot electrons

abstract:
  We study correlated transport in a Josephson junction array for small
Josephson energies. In this regime transport is dominated by Cooper-pair
hopping, although we observe that quasiparticles can not be neglected. We
assume that the energy dissipated by a Cooper-pair is absorbed by the intrinsic
impedance of the array. This allows us to formulate explicit Cooper-pair
hopping rates without adding any parameters to the system. We show that the
current is correlated and crucially, these correlations rely fundamentally on
the interplay between the Cooper-pairs and equilibrium quasiparticles.


title: An improved method to test the Distance--Duality relation

abstract:
  Many researchers have performed cosmological-model-independent tests for the
distance duality (DD) relation. Theoretical work has been conducted based on
the results of these tests. However, we find that almost all of these tests
were perhaps not cosmological-model-independent after all, because the distance
moduli taken from a given type Ia supernovae (SNe Ia) compilation are dependent
on a given cosmological model and Hubble constant. In this Letter, we overcome
these defects and by creating a new cosmological-model-independent test for the
DD relation. We use the original data from the Union2 SNe Ia compilation and
the angular diameter distances from two galaxy cluster samples compiled by De
Filippis et al. and Bonamente et al. to test the DD relation. Our results
suggest that the DD relation is compatible with observations, and the spherical
model is slightly better than the elliptical model at describing the intrinsic
shape of galaxy clusters if the DD relation is valid. However, these results
are different from those of previous work.


title:
Nonparametric reconstruction of dynamical dark energy via observational
  Hubble parameter data

abstract:
  We study the power of current and future observational Hubble parameter data
(OHD) on non-parametric estimations of the dark energy equation of state,
$w(z)$. We propose a new method by conjunction of principal component analysis
(PCA) and the criterion of goodness of fit (GoF) criterion to reconstruct
$w(z)$, ensuring the sensitivity and reliability of the extraction of features
in the EoS. We also give an new error model to simulate future OHD data, to
forecast the power of future OHD on the EoS reconstruction. The result shows
that current OHD, despite in less quantity, give not only a similar power of
reconstruction of dark energy compared to the result given by type Ia
supernovae, but also extend the constraint on $w(z)$ up to redshift $z\simeq2$.
Additionally, a reasonable forecast of future data in more quantity and better
quality greatly enhances the reconstruction of dark energy.


title:
Nucleon-Nucleon Spin Dependent Scattering Amplitudes to Describe Final
  State Interactions in Electromagnetic and Electroweak Nuclear Processes

abstract:
  There are currently no models readily available that provide nucleon-nucleon
spin dependent scattering amplitudes at high energies ($s \geq 6$ GeV$^2$).
This work aims to provide a model for calculating these high-energy scattering
amplitudes. The foundation of the model is Regge theory since it allows for a
relativistic description and full spin dependence. A parameterization of the
amplitudes is presented, and comparisons of the solution to the assembled data
set are shown. In addition, an application of the model to describe final state
interactions in deuteron electrodisintegration is presented. Overall the model
works as intended, and provides an adequate description of the nucleon-nucleon
interaction at these energies.


title: Link Performance Abstraction for Interference-Aware Communications (IAC)

abstract:
  Advanced co-channel interference aware signal detection has drawn research
attention during the recent development of Long Term Evolution-Advanced (LTE-A)
systems and the interference-aware communications (IAC) is currently being
studied by 3GPP. This paper investigates link performance abstraction for the
IAC systems employing maximum-likelihood detector (MLD). The link performance
of MLD can be estimated by combining two performance bounds, namely, linear
receiver and genie-aided maximum-likelihood (ML) receiver. It is shown that the
conventional static approach based on static parameterization, while working
well under moderate and weak interference conditions, fails to generate a
well-behaved solution in the strong interference case. Inspired by this
observation, we propose a new adaptive approach where the combining parameter
is adaptively adjusted according to instantaneous interference-to-signal ratio
(ISR). The basic idea is to exploit the probabilistic behavior of the optimal
combining ratio over the ISR. The link-level simulation results are provided to
verify the prediction accuracy of the proposed link abstraction method.
Moreover, we use the proposed link abstraction model as a link-to-system
interface mapping in system-level simulations to demonstrate the performance of
the IAC receiver in interference-limited LTE systems


title: Phase Retrieval for Sparse Signals

abstract:
  The aim of this paper is to build up the theoretical framework for the
recovery of sparse signals from the magnitude of the measurement. We first
investigate the minimal number of measurements for the success of the recovery
of sparse signals without the phase information. We completely settle the
minimality question for the real case and give a lower bound for the complex
case. We then study the recovery performance of the $\ell_1$ minimization. In
particular, we present the null space property which, to our knowledge, is the
first sufficient and necessary condition for the success of $\ell_1$
minimization for $k$-sparse phase retrievable.


title: A Search for Optical Variability of Type 2 Quasars in SDSS Stripe 82

abstract:
  Hundreds of Type 2 quasars have been identified in Sloan Digital Sky Survey
(SDSS) data, and there is substantial evidence that they are generally galaxies
with highly obscured central engines, in accord with unified models for active
galactic nuclei (AGNs). A straightforward expectation of unified models is that
highly obscured Type 2 AGNs should show little or no optical variability on
timescales of days to years. As a test of this prediction, we have carried out
a search for variability in Type 2 quasars in SDSS Stripe 82 using
difference-imaging photometry. Starting with the Type 2 AGN catalogs of
Zakamska et al. (2003) and Reyes et al. (2008), we find evidence of significant
g-band variability in 17 out of 173 objects for which light curves could be
measured from the Stripe 82 data. To determine the nature of this variability,
we obtained new Keck spectropolarimetry observations for seven of these
variable AGNs. The Keck data show that these objects have low continuum
polarizations (p<~1% in most cases) and all seven have broad H-alpha and/or
MgII emission lines in their total (unpolarized) spectra, indicating that they
should actually be classified as Type 1 AGNs. We conclude that the primary
reason variability is found in the SDSS-selected Type 2 AGN samples is that
these samples contain a small fraction of Type 1 AGNs as contaminants, and it
is not necessary to invoke more exotic possible explanations such as a
population of "naked" or unobscured Type 2 quasars. Aside from misclassified
Type 1 objects, the Type 2 quasars do not generally show detectable optical
variability over the duration of the Stripe 82 survey.


title: Parsec-scale structure of quasars: dawn of the golden age?

abstract:
  Half a century after their discovery, the study of quasars remains one of the
most fascinating intellectual challenges in astronomy. Quasars are laboratories
for everything from relativity to magnetohydrodynamics and are perhaps the best
available probes for cosmology. A tremendous amount has been learned about
quasars and yet many of the most fundamental questions about their physics
remain open. Parsec-scale observations have played an indispensable role in
building up our current understanding of quasars; virtually everything we know
about quasars depends on such observations. However, the finest hour for parsec
scale observations may be just beginning. This is partly due to the development
of highly reliable VLBI networks (which is continuing) but mostly due to the
unprecedented availability of multiepoch, simultaneous, broadband observations
that have long been the `holy grail' for quasar researchers.


title: Lepton-number violation in B decays at BaBar

abstract:
  We present results of searches for lepton-number and baryon-number violation
in B decays using the full BaBar dataset of 471 million BBbar pairs.


title: Vortices in spinor cold exciton condensates with spin-orbit interaction

abstract:
  We study theoretically the ground states of topological defects in a spinor
four-component condensate of cold indirect excitons. We analyze possible ground
state solutions for different configurations of vortices and half-vortices. We
show that if only Rashba or Dreselhaus spin-orbit interaction (SOI) for
electrons is present the stable states of topological defects can represent a
cylindrically symmetric half-vortex or half vortex-antivortex pairs, or a
non-trivial pattern with warped vortices. In the presence of both of Rashba and
Dresselhaus SOI the ground state of a condensate represents a stripe phase and
vortex type solutions become unstable.


title: Modification of jet shapes in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

abstract:
  The first measurement of jet shapes, defined as the fractional transverse
momentum radial distribution, for inclusive jets produced in heavy-ion
collisions is presented. Data samples of PbPb and pp collisions, corresponding
to integrated luminosities of 150 inverse microbarns and 5.3 inverse picobarns
respectively, were collected at a nucleon-nucleon centre-of-mass energy of
sqrt(s[NN]) = 2.76 TeV with the CMS detector at the LHC. The jets are
reconstructed with the anti-kt algorithm with a distance parameter R = 0.3, and
the jet shapes are measured for charged particles with transverse momentum pt >
1 GeV. The jet shapes measured in PbPb collisions in different collision
centralities are compared to reference distributions based on the pp data. A
centrality-dependent modification of the jet shapes is observed in the more
central PbPb collisions, indicating a redistribution of the energy inside the
jet cone. This measurement provides information about the parton shower
mechanism in the hot and dense medium produced in heavy-ion collisions.


title: The Effect of the Remnant Mass in Estimating Stellar Mass of Galaxies

abstract:
  The definition of the galactic stellar mass estimated from the spectral
energy distribution is ambiguous in the literature; whether the stellar mass
includes the mass of the stellar remnants, i.e. white dwarfs, neutron stars,
and black holes, is not well described. The remnant mass fraction in the total
(living+remnant) stellar mass of a simple stellar population monotonically
increases with the age of the population, and the initial mass function and
metallicity affect the increasing rate. Since galaxies are composed of a number
of stellar populations, the remnant mass fraction may depend on the total
stellar mass of galaxies in a complex way. As a result, the shape of the
stellar mass function of galaxies may change, depending on the definition of
the stellar mass. In order to explore this issue, we ran a cosmological
hydrodynamical simulation, and then, we have found that the remnant mass
fraction indeed correlates with the total stellar mass of galaxies. However,
this correlation is weak and the remnant fraction can be regarded as a constant
which depends only on the redshift. Therefore, the shape of the stellar mass
function is almost unchanged, but it simply shifts horizontally if the remnant
mass includes or not. The shift is larger at lower redshift and it reaches
0.2-dex at z=0 for a Chabrier IMF. Since this causes a systematic difference,
we should take care of the definition of the `stellar' mass, when comparing
one's result with others.


title:
Neel to spin-Peierls transition in a quasi-1D Heisenberg model coupled
  to bond phonons

abstract:
  The zero and finite temperature spin-Peierls transitions in a
quasi-one-dimensional spin-1/2 Heisenberg model coupled to adiabatic bond
phonons is investigated using the Stochastic Series Expansion (SSE) Quantum
Monte Carlo (QMC) method. The quantum phase transition from a gapless Neel
state to a spin-gapped Peierls state is studied in the parameter space spanned
by spatial anisotropy, inter-chain coupling strength and spin-lattice coupling
strength. It is found that for any finite inter-chain coupling, the transition
to a dimerized Peierls ground state only occurs when the spin-lattice coupling
exceeds a finite, non-zero critical value. This is in contrast to the pure 1D
model (zero inter-chain coupling), where adiabatic/classical phonons lead to a
dimerized ground state for any non-zero spin-phonon interaction. The phase
diagram in the parameter space shows that for a strong inter-chain coupling,
the relation between the inter-chain coupling and the critical value of the
spin-phonon interaction is linear whereas for weak inter-chain coupling, this
behavior is found to have a natural logarithm-like relation. No region was
found to have a long range magnetic order and dimerization occurring
simultaneously. Instead, the Neel state order vanishes simultaneously with the
setting in of the spin-Peierls state. For the thermal phase transition, a
continuous heat capacity with a peak at the critical temperature, $T_{c}$,
shows a second order phase transition. The variation of the equilibrium bond
length distortion, $\delta_{eq}$, with temperature showed a power law relation
which decayed to zero as the temperature was increased to $T_{c}$, indicating a
continuous transition from the dimerized phase to a paramagnetic phase with
uniform bond length and zero antiferromagnetic susceptibility.


title:
Effects of interface electric field on the magnetoresistance in spin
  device

abstract:
  An extension of the standard spin diffusion theory is presented by
introducing a density-gradient (DG) term that is suitable for describing
interface quantum tunneling phenomena. The magnetoresistance (MR) ratio is
modified by the DG term through an interface electric field. We have also
carried out spin injection and detection measurements using four-terminal Si
devices. The local measurement shows that the MR ratio changes depending on the
current direction. We show that the change of the MR ratio depending on the
current direction comes from the DG term regarding the asymmetry of the two
interface electronic structures.


title: A Room-temperature Spin-polarized Polariton Laser

abstract:
  In the field of spin-controlled semiconductor lasers, massive effort has been
focused upon materials with long spin relaxation times (~ns). In contrast, we
demonstrate room-temperature spin-polarized ultrafast pulsed lasing in InGaAs
quantum wells (~10 ps) embedded within a GaAs microcavity. The microcavity
studied here is similar to vertical-cavity surface-emitting lasers (VCSEL) used
in optical communication. Unlike a VCSEL, the present polariton laser has
nonlinear output and energy shifts owing to the mixing of the free-carrier
polarization and cavity light field. At room temperature, we observe features
resembling those in exciton-polariton condensates at cryogenic temperatures,
including the spontaneous build-up of spatial coherence, macroscopic
occupation, and spin polarization. Our results should stimulate activities to
exploit spin-orbit interaction and many-body effects for fundamental studies of
quantum light-matter fluids and developments of spin-dependent optoelectronic
devices.


title:
Scalable Protein Sequence Similarity Search using Locality-Sensitive
  Hashing and MapReduce

abstract:
  Metagenomics is the study of environments through genetic sampling of their
microbiota. Metagenomic studies produce large datasets that are estimated to
grow at a faster rate than the available computational capacity. A key step in
the study of metagenome data is sequence similarity searching which is
computationally intensive over large datasets. Tools such as BLAST require
large dedicated computing infrastructure to perform such analysis and may not
be available to every researcher.
  In this paper, we propose a novel approach called ScalLoPS that performs
searching on protein sequence datasets using LSH (Locality-Sensitive Hashing)
that is implemented using the MapReduce distributed framework. ScalLoPS is
designed to scale across computing resources sourced from cloud computing
providers. We present the design and implementation of ScalLoPS followed by
evaluation with datasets derived from both traditional as well as metagenomic
studies. Our experiments show that with this method approximates the quality of
BLAST results while improving the scalability of protein sequence search.


title: Synthetic spin-orbit interactions and magnetic fields in ring-cavity QED

abstract:
  The interactions between light and matter are strongly enhanced when atoms
are placed in high-finesse quantum cavities, offering tantalizing opportunities
for generating exotic new quantum phases. In this work we show that both
spin-orbit interactions and strong synthetic magnetic fields result when a
neutral atom is confined within a ring cavity, whenever the internal atomic
states are coupled to two off-resonant counter-propagating modes. We
diagonalize the resulting cavity polariton Hamiltonian and find characteristic
spin-orbit dispersion relations for a wide range of parameters. An adjustable
uniform gauge potential is also generated, which can be converted into a
synthetic magnetic field for neutral atoms by applying an external magnetic
field gradient. Very large synthetic magnetic fields are possible as the
strength is proportional to the (average) number of photons in each of the
cavity modes. The results suggest that strong-coupling cavity quantum
electrodynamics can be a useful environment for the formation of topological
states in atomic systems.


title: Establishment of the new Ecuadorian solar physics phenomena division

abstract:
  Crucial physical phenomena occur in the equatorial atmosphere and ionosphere,
which are currently understudied and poorly understood. Then, scientific
campaigns for monitoring equatorial region are required, which will provide the
data for analyzing and creating adequate models. Ecuador is located in
strategic geographical position where these studies can be performed, providing
data for the scientific community working for understanding the nature of these
physical systems. The Quito Astronomical Observatory of National Polytechnic
School is working in this direction, promoting research in Space Sciences for
studying the equatorial zone. With the participation and valuable collaboration
of international initiatives like AWESOME, MAGDAS, SAVNET and CALLISTO, the
Quito Observatory is creating a new space physics division on the basis of the
International Space Weather Initiative. In this contribution, the
aforementioned initiative is presented inviting leaders from others scientific
projects to deploy their instruments and to join us giving the necessary
support for the creation of this new strategic research center.


title: First Magdas Equipment In Ecuador

abstract:
  The Magnetic Data Acquisition System (MAGDAS) was installed in the protected
Jerusalem Park in Malchingui-Ecuador in October of 2012, under the joint
collaboration between Kyushu University of Japan and the Quito Astronomical
Observatory of the National Polytechnic School of Ecuador. In this paper, we
describe the installation process and present the preliminary data obtained
with the MAGDAS equipment. The behavior of the four components, D, H, Z and F
allow us to see the importance of having the Ecuador station where the magnetic
field has not been systematically measured before, in valuable contribution to
study of the equatorial atmosphere.


title: An analysis of HDG methods for convection dominated diffusion problems

abstract:
  In this paper, we establish an a priori error analysis of HDG methods with
two types of stabilization parameter applied to convection dominated diffusion
problem. We show that, using polynomials of degree no greater than k, L2 error
of the scalar variable of HDG methods converges in order k + 1/2 if the meshes
are not aligned with the flux. This result implies that the HDG approximation
converges as fast as conventional DG methods. In the case that the meshes are
aligned with the flux, we show that HDG methods with the second type of
stabilization parameter achieves optimal rate of convergence. We also discuss
preferred form for implementation of HDG methods. In appendix, we show that the
spectral condition number of stiffness matrix of HDG methods is independent of
the diffusion coefficient. Numerical experiments are presented to verify our
theoretical results.


title: Skin supersolidity slipperizing ice

abstract:
  Consistency between theory predictions and measurements and calculations
revealed that the skin of ice, containing water molecules with fewer than four
neighbours, forms a supersolid phase that is highly polarized, elastic,
hydrophobic, with ultra-low density and high thermal stability. The
supersolidity of skin sliperizes ice.


title:
Structural flexibility of intrinsically disordered proteins induces
  stepwise target recognition

abstract:
  An intrinsically disordered protein (IDP) lacks a stable three-dimensional
structure, while it folds into a specific structure when it binds to a target
molecule. In some IDP-target complexes, not all target binding surfaces are
exposed on the outside, and intermediate states are observed in their binding
processes. We consider that stepwise target recognition via intermediate states
is a characteristic of IDP binding to targets with "hidden" binding sites. To
investigate IDP binding to hidden target binding sites, we constructed an IDP
lattice model based on the HP model. In our model, the IDP is modeled as a
chain and the target is modeled as a highly coarse-grained object. We
introduced motion and internal interactions to the target to hide its binding
sites. In the case of unhidden binding sites, a two-state transition between
the free states and a bound state is observed, and we consider that this
represents coupled folding and binding. Introducing hidden binding sites, we
found an intermediate bound state in which the IDP forms various structures to
temporarily stabilize the complex. The intermediate state provides a scaffold
for the IDP to access the hidden binding site. We call this process multiform
binding. We conclude that structural flexibility of IDPs enables them to access
hidden binding sites, and this is a functional advantage of IDPs.


title:
Multiple Kernel Learning in the Primal for Multi-modal Alzheimer's
  Disease Classification

abstract:
  To achieve effective and efficient detection of Alzheimer's disease (AD),
many machine learning methods have been introduced into this realm. However,
the general case of limited training samples, as well as different feature
representations typically makes this problem challenging. In this work, we
propose a novel multiple kernel learning framework to combine multi-modal
features for AD classification, which is scalable and easy to implement.
Contrary to the usual way of solving the problem in the dual space, we look at
the optimization from a new perspective. By conducting Fourier transform on the
Gaussian kernel, we explicitly compute the mapping function, which leads to a
more straightforward solution of the problem in the primal space. Furthermore,
we impose the mixed $L_{21}$ norm constraint on the kernel weights, known as
the group lasso regularization, to enforce group sparsity among different
feature modalities. This actually acts as a role of feature modality selection,
while at the same time exploiting complementary information among different
kernels. Therefore it is able to extract the most discriminative features for
classification. Experiments on the ADNI data set demonstrate the effectiveness
of the proposed method.


title: Prikry-type forcing and minimal $\alpha$-degree

abstract:
  In this paper, we introduce several classes of Prikry-type forcing notions,
two of which are used to produce minimal generic extensions, and the third is
applied in $\alpha$-recursion theory to produce minimal covers. The first
forcing as a warm up yields a minimal generic extension at a measurable
cardinal (in $V$), the second at an $\omega$-limit of measurable cardinals
$\langle\gamma_n\colon n<\omega\rangle$ such that each $\gamma_n$ ($n>0$)
carries $\gamma_{n-1}$-many normal measures. Via a notion of $V_\gamma $-degree
(see Definition \ref{def:vgammadegree}), we transfer the second Prikry-type
construction for minimal generic extensions to a construction for minimal
degrees in $\alpha$-recursion theory. More explicitly, \begin{theorem*} Suppose
$\langle\gamma_n\colon n<\omega\rangle$ is a strictly increasing sequence of
measurable cardinals such that for each $n>0$, $\gamma_n$ carries at least
$\gamma_{n-1}$-many normal measures. Let $\gamma=\sup\{\gamma_n\colon
n<\omega\}$. %Then for each $n$, $\gamma$ is $\Sigma_n$-admissible. Then there
is an $A\subset\gamma$ such that \begin{itemize} \item[(a)]
$(L_{\gamma},\in,A)$ is not admissible. \item[(b)] The $\gamma$-degree that
contains $A$ has a minimal cover. \end{itemize} \end{theorem*}


title:
Discrete Imaging Models for Three-Dimensional Optoacoustic Tomography
  using Radially Symmetric Expansion Functions

abstract:
  Optoacoustic tomography (OAT), also known as photoacoustic tomography, is an
emerging computed biomedical imaging modality that exploits optical contrast
and ultrasonic detection principles. Iterative image reconstruction algorithms
that are based on discrete imaging models are actively being developed for OAT
due to their ability to improve image quality by incorporating accurate models
of the imaging physics, instrument response, and measurement noise. In this
work, we investigate the use of discrete imaging models based on Kaiser-Bessel
window functions for iterative image reconstruction in OAT. A closed-form
expression for the pressure produced by a Kaiser-Bessel function is calculated,
which facilitates accurate computation of the system matrix.
Computer-simulation and experimental studies are employed to demonstrate the
potential advantages of Kaiser-Bessel function-based iterative image
reconstruction in OAT.


title:
Mediation of hydrogen-bond coupling interactions by programmable heating
  and salting

abstract:
  We show that programmable heating and salting share the same effect on the
frequency shift of the O:H and the H-O stretching phonons of the O:H-O hydrogen
bond, which revealed that both heating and salting lengthens and softens the
O:H bond and shortens and stiffens the H-O bond due to the weakening of the
Coulomb repulsion between electron pairs of adjacent oxygen atoms.
Understanding provides possible mechanism for the Hofmeister series and the
detergent effect on cloth cleaning.


title: Differential Data Analysis for Recommender Systems

abstract:
  We present techniques to characterize which data is important to a
recommender system and which is not. Important data is data that contributes
most to the accuracy of the recommendation algorithm, while less important data
contributes less to the accuracy or even decreases it. Characterizing the
importance of data has two potential direct benefits: (1) increased privacy and
(2) reduced data management costs, including storage. For privacy, we enable
increased recommendation accuracy for comparable privacy levels using existing
data obfuscation techniques. For storage, our results indicate that we can
achieve large reductions in recommendation data and yet maintain recommendation
accuracy.
  Our main technique is called differential data analysis. The name is inspired
by other sorts of differential analysis, such as differential power analysis
and differential cryptanalysis, where insight comes through analysis of
slightly differing inputs. In differential data analysis we chunk the data and
compare results in the presence or absence of each chunk. We present results
applying differential data analysis to two datasets and three different kinds
of attributes. The first attribute is called user hardship. This is a novel
attribute, particularly relevant to location datasets, that indicates how
burdensome a data point was to achieve. The second and third attributes are
more standard: timestamp and user rating. For user rating, we confirm previous
work concerning the increased importance to the recommender of data
corresponding to high and low user ratings.


title:
A Thom-Porteous formula for connective K-theory using algebraic
  cobordism

abstract:
  We prove a formula for the push-forward class of Bott-Samelson resolutions in
the algebraic cobordism ring of the flag bundle. We specialise our formula to
connective K-theory providing a geometric interpretation to the double
beta-polynomials of Fomin and Kirillov by computing the fundamental classes of
Schubert varieties. As a corollary we obtain a Thom-Porteous formula
generalising those of the Chow ring and of the Grothendieck ring of vector
bundles.


title: On isotropic divisors on irreducible symplectic manifolds

abstract:
  Let X be an irreducible symplectic manifold and L a divisor on X. Assume that
L is isotropic with respect to the Beauville-Bogomolov quadratic form. We
define the rational Lagrangian locus and the movable locus on the universal
deformation space of the pair (X, L). We prove that the rational Lagrangian
locus is empty or coincide with the movable locus.


title: A New Generalization of Fermat's Last Theorem

abstract:
  In this paper, we consider some hybrid Diophantine equations of addition and
multiplication. We first improve a result on new Hilbert-Waring problem. Then
we consider the equation \begin{equation}
  \begin{cases}
  A+B=C
  ABC=D^n
  \end{cases} \end{equation} where $A,B,C,D,n \in\ZZ_{+}$ and $n\geq3$, which
may be regarded as a generalization of Fermat's equation $x^n+y^n=z^n$. When
$\gcd(A,B,C)=1$, $(1)$ is equivalent to Fermat's equation, which means it has
no positive integer solutions. We discuss several cases for $\gcd(A,B,C)=p^k$
where $p$ is an odd prime. In particular, for $k=1$ we prove that $(1)$ has no
nonzero integer solutions when $n=3$ and we conjecture that it is also true for
any prime $n>3$. Finally, we consider equation $(1)$ in quadratic fields
$\mathbb{Q}(\sqrt{t})$ for $n=3$.


title: Perfect numbers and Fibonacci primes

abstract:
  In this paper, we introduce the concept of $F$-perfect number, which is a
positive integer $n$ such that $\sum_{d|n,d<n}d^2=3n$. We prove that all the
$F$-perfect numbers are of the form $n=F_{2k-1}F_{2k+1}$, where both $F_{2k-1}$
and $F_{2k+1}$ are Fibonacci primes. Moreover, we obtain other interesting
results and raise a new conjecture on perfect numbers.


title: Conic Geometric Programming

abstract:
  We introduce and study conic geometric programs (CGPs), which are convex
optimization problems that unify geometric programs (GPs) and conic
optimization problems such as semidefinite programs (SDPs). A CGP consists of a
linear objective function that is to be minimized subject to affine
constraints, convex conic constraints, and upper bound constraints on sums of
exponential and affine functions. The conic constraints are the central feature
of conic programs such as SDPs, while upper bounds on combined
exponential/affine functions are generalizations of the types of constraints
found in GPs. The dual of a CGP involves the maximization of the negative
relative entropy between two nonnegative vectors jointly, subject to affine and
conic constraints on the two vectors. Although CGPs contain GPs and SDPs as
special instances, computing global optima of CGPs is not much harder than
solving GPs and SDPs. More broadly, the CGP framework facilitates a range of
new applications that fall outside the scope of SDPs and GPs. Specifically, we
demonstrate the utility of CGPs in providing solutions to problems such as
permanent maximization, hitting-time estimation in dynamical systems, the
computation of the capacity of channels transmitting quantum information, and
robust optimization formulations of GPs.


title:
Efficient pedestrian detection by directly optimize the partial area
  under the ROC curve

abstract:
  Many typical applications of object detection operate within a prescribed
false-positive range. In this situation the performance of a detector should be
assessed on the basis of the area under the ROC curve over that range, rather
than over the full curve, as the performance outside the range is irrelevant.
  This measure is labelled as the partial area under the ROC curve (pAUC).
Effective cascade-based classification, for example, depends on training node
classifiers that achieve the maximal detection rate at a moderate false
positive rate, e.g., around 40% to 50%. We propose a novel ensemble learning
method which achieves a maximal detection rate at a user-defined range of false
positive rates by directly optimizing the partial AUC using structured
learning. By optimizing for different ranges of false positive rates, the
proposed method can be used to train either a single strong classifier or a
node classifier forming part of a cascade classifier. Experimental results on
both synthetic and real-world data sets demonstrate the effectiveness of our
approach, and we show that it is possible to train state-of-the-art pedestrian
detectors using the proposed structured ensemble learning method.


title: Cudagrind: A Valgrind Extension for CUDA

abstract:
  Valgrind, and specifically the included tool Memcheck, offers an easy and
reliable way for checking the correctness of memory operations in programs.
This works in an unintrusive way where Valgrind translates the program into
intermediate code and executes it on an emulated CPU. The heavy weight tool
Memcheck uses this to keep a full shadow copy of the memory used by a program
and tracking accesses to it. This allows the detection of memory leaks and
checking the validity of accesses.
  Though suited for a wide variety of programs, this approach still fails when
accelerator based programming models are involved. The code running on these
devices is separate from the code running on the host. Access to memory on the
device and starting of kernels is being handled by an API provided by the
driver being used. Hence Valgrind is unable to understand and instrument
operations being run on the device.
  To circumvent this limitation a new set of wrapper functions have been
introduced. These wrap a subset of the CUDA Driver API function that is
responsible for (de-)allocation memory regions on the device and the respective
memory copy operations. This allows to check whether memory is fully allocated
during a transfer and, through the functionality provided by Valgrind, whether
the memory transfered to the device from the host is defined and addressable.
Through this technique it is possible to detect a number of common programming
mistakes, which are very difficult to debug by other means. The combination of
these wrappers together with the Valgrind tool Memcheck is being called
Cudagrind.


title:
A Note on Large N Thermal Free Energy in Supersymmetric Chern-Simons
  Vector Models

abstract:
  We compute the exact effective action for \cN=3 U(N)_k and \cN=4,6
U(N)_k\times U(N')_{-k} Chern-Simons theories with minimal matter content in
the 't Hooft vector model limit under which N and k go to infinity holding N/k,
N' fixed. We also extend this calculation to \cN=4,6 mass deformed case. We
show those large N effective actions except mass-deformed \cN=6 case precisely
reduce to that of \cN=2 U(N)_k Chern-Simons theory with one fundamental chiral
field up to overall multiple factor. By using this result we argue the thermal
free energy and self-duality of the \cN=3,4,6 Chern-Simons theories including
the \cN=4 mass term reduce to those of the \cN=2 case under the limit.


title: Topological = total

abstract:
  A notion of central importance in categorical topology is that of topological
functor. A faithful functor E -> B is called topological if it admits cartesian
liftings of all (possibly large) families of arrows; the basic example is the
forgetful functor Top -> Set. A topological functor E -> 1 is the same thing as
a (large) complete preorder, and the general topological functor E -> B is
intuitively thought of as a complete preorder relative to B. We make this
intuition precise by considering an enrichment base Q_B such that Q_B-enriched
categories are faithful functors into B, and show that, in this context, a
faithful functor is topological if and only if it is total (=totally
cocomplete) in the sense of Street--Walters. We also consider the MacNeille
completion of a faithful functor to a topological one, first described by
Herrlich, and show that it may be obtained as an instance of Isbell's
generalised notion of MacNeille completion for enriched categories.


title: A counterexample to the containment $I^{(3)}\subset I^2$ over the reals

abstract:
  The purpose of this note is to give counterexamples to the containment
$I^{(3)}\subset I^2$ over the real numbers.


title:
Relativistic Spin and Dirac Spin in relativistically covariant
  Stern-Gerlach Experiment

abstract:
  We have studied a relativistically covariant Stern-Gerlach (SG) experiment
for a relativistic spin and a Dirac spin. We have obtained the relativistic
spin in an arbitrary frame by using the classical spin dipole tensor, which
gives the covariant spin dipole interactions, and the relation between a spin
and a spin magnetic dipole moment. The relativistic spin is shown to have
problems to become a proper spin operator for a massive relativistic particle
because of two reasons. First, the relativistic spin three-vector operators
cannot satisfy the spin algebra. Second, the SG experiment for the relativistic
particle provides a paradox between two observers in the particle rest frame
and the laboratory frame, in which the particle is moving. We have shown that
the paradox in the SG experiment is resolved by the Dirac spin, which is
covariantly defined by a Lorentz transformation in the Dirac spinor
representation. The Dirac spin three-vector operators satisfy the spin algebra.
It is shown that the SG experiment for the Dirac spin in the inertial frame,
where there is only magnetic field, can determine the spin without the
information of the momentum of the particle.
  This shows that the reduced spin density matrix for the Dirac particle can be
well-defined by integrating out the momentum degrees of freedom.


title: Massless collective excitations in frustrated multi-band superconductors

abstract:
  We study collective excitations in three- and four-band superconductors with
inter-band frustration, which causes neither 0 nor $\pi$ inter-band phases in
the superconducting state. Using a low-energy spin-Hamiltonian originating from
a multi-band tight-binding model, we find that a massless Leggett mode occurs
in a wide parameter region of this four-band system. This massless mode is
related to the fact that the mean-field energy does not depend on a continuous
superconducting phase. In other words, we find a link of the massless mode with
a degeneracy between a time-reversal-symmetry-breaking state (neither 0 nor
$\pi$ phases) and a time-reversal-symmetric state (either 0 or $\pi$ phases).
Therefore, the mass of this collective mode characterizes well the
time-reversal symmetry in frustrated multi-band superconductors.


title:
A study of the high-inclination population in the Kuiper belt -- 1. The
  Plutinos

abstract:
  The dynamics of the high-inclination Plutinos is systematically studied. We
first present the peculiar features of the 2:3 Neptune mean motion resonance
(NMMR) for inclined orbits, especially for the correlation of resonant
amplitude A_{\sigma} with inclination i. Using the numerical integrations for
the age of the Solar system, the dynamical structure of the 2:3 NMMR is mapped
out on the plane of semi-major axis versus i for different eccentricities. We
have shown that i of stable resonant orbits could be as high as 90 deg; and the
stable region is roughly surrounded by the contours of A_{\sigma} = 120 deg.
These new findings allow us to further explore the 2:3 NMMR capture and
retention of planetesimals with initial inclinations i0 =< 90 deg in the frame
of the planet migration model. We find that the outward transportation of
Plutinos is possible for any inclined or even perpendicular orbits.
  The role of i0 in the formation of Plutinos during Neptune's migration is
highlighted and interesting results are obtained: (1) The capture efficiency of
the 2:3 NMMR decreases drastically first with the increase of i0, but it then
raises instead when i0 exceeds ~ 50 deg; (2) The magnitude of i-variation is
limited to less than 5 deg for any i0, and moreover, for Plutinos with i > 48
deg, their i are forced to decrease throughout the outward migration; (3)
Plutinos with i > 48 deg are certainly outside the Kozai mechanism, since an
inclination increase is prohibited by the migrating 2:3 NMMR; (4) The 7:11
inclination-type NMMR could be responsible for nearly-circular Plutinos, and a
minimum i0 ~ 15 deg is required to intrigue this mechanism.


title: Present status of two-dimensional ESTER models: Application to Be stars

abstract:
  ESTER two-dimensional models solve the steady state structure of fast
rotating early-type stars including the large scale flows associated with the
baroclinicity of the radiative zones. Models are compared successfully to the
fundamental parameters of the two main components of the triple system $\delta$
Velorum that have been derived from interferometric and orbit measurements.
Testing the models on the Be star Achernar ($\alpha$ Eri), we cannot reproduce
the data and conclude that this star has left the main sequence and is likely
crossing the Herzsprung gap. Computing main sequence evolution of fast rotating
stars at constant angular momentum shows that their criticality increases with
time suggesting that the Be phenomenon and the ensuing mass ejections is the
result of evolution.


title:
Global-in-time Strichartz estimates on non-trapping asymptotically conic
  manifolds

abstract:
  We prove global-in-time Strichartz estimates without loss of derivatives for
the solution of the Schroedinger equation on a class of non-trapping
asymptotically conic manifolds. We obtain estimates for the full set of
admissible indices, including the endpoint, in both the homogeneous and
inhomogeneous cases. This result improves on the results in earlier papers of
Hassell-Tao-Wunsch and Mizutani which were local in time.


title: Helly type theorems for the sum of vectors in a normed plane

abstract:
  The main results here are two Helly type theorems for the sum of (at most)
unit vectors in a normed plane. Also, we give a new characterization of
centrally symmetric convex sets in the plane.


title:
On the heat diffusion for generic Riemannian and sub-Riemannian
  structures

abstract:
  In this paper we provide the small-time heat kernel asymptotics at the cut
locus in three relevant cases: generic low-dimensional Riemannian manifolds,
generic 3D contact sub-Riemannian manifolds (close to the starting point) and
generic 4D quasi-contact sub-Riemannian manifolds (close to a generic starting
point). As a byproduct, we show that, for generic low-dimensional Riemannian
manifolds, the only singularities of the exponential map, as a Lagragian map,
that can arise along a minimizing geodesic are $A_3$ and $A_5$ (in the
classification of Arnol'd's school). We show that in the non-generic case, a
cornucopia of asymptotics can occur, even for Riemannian surfaces.


title:
When to Bite the Bullet? - A Study of Optimal Strategies for Reducing
  Global Warming

abstract:
  This work is based on the framework proposed by Conrad (1997) to determine
the optimal timing of an investment or policy to slow global warming. While
Conrad formulated the problem as a stopping rule option pricing model, we treat
the policy decision by considering the total damage function that enables us to
make some interesting extensions to the original formulation. We show that
Conrad's framework is equivalent to minmization of the expected value of the
damage function under the stochastic optimal stopping rule. We extend Conrad's
model by allowing for policy cost to grow with time. In addition to closed form
solution, we also perform Monte Carlo simulations to find the distribution for
the total damage and show that at higher quantiles the damage may become too
large and so is the risk on the global economy. We also show that the decision
to take action largely depends on the cost of the action. For example, in the
case of model parameters calibrated as in Conrad (1997) with a constant cost,
there is a rather long wait before the action is expected to be taken, but if
the cost increases with the same rate as the global economy growth, then action
has to be taken immediately to minimize the damage.


title: Appearance of a quark matter phase in hybrid stars

abstract:
  The appearance of quark matter in the core of hybrid stars is a fundamental
issue in such compact stars. The central density of these stars is sufficiently
high such that nuclear matter undergoes a further change into other exotic
phases that consist of hyperons and quarks. However, the equation of state
(EOS) for the high-density matter is still not clear and several recent
observations have indicated the limitations of the EOSs; theoretical studies
should try to elucidate the EOSs. It is believed that the inner regions of the
stars should consist of a mixed hadron-quark phase. We study the mixed
hadron-quark phase, taking into account finite-size effects, and find that that
the mixed phase should be restricted to a narrower region. Therefore, a quark
matter phase should appear in the central region.


title: Witten's loop in the flipped SU(5) unification

abstract:
  We study a very simple, yet potentially realistic renormalizable flipped
SU(5) scenario in which the right-handed neutrino masses are generated at very
high energies by means of a two-loop diagram similar to that identified by E.
Witten in the early 1980's in the SO(10) GUT framework. This mechanism leaves
its traces in the baryon number violating signals such as the proton decay,
especially in the "clean" channels with a charged lepton and a neutral meson in
the final state.