title:
Gaussian Process-Based Decentralized Data Fusion and Active Sensing for
  Mobility-on-Demand System

abstract:
  Mobility-on-demand (MoD) systems have recently emerged as a promising
paradigm of one-way vehicle sharing for sustainable personal urban mobility in
densely populated cities. In this paper, we enhance the capability of a MoD
system by deploying robotic shared vehicles that can autonomously cruise the
streets to be hailed by users. A key challenge to managing the MoD system
effectively is that of real-time, fine-grained mobility demand sensing and
prediction. This paper presents a novel decentralized data fusion and active
sensing algorithm for real-time, fine-grained mobility demand sensing and
prediction with a fleet of autonomous robotic vehicles in a MoD system. Our
Gaussian process (GP)-based decentralized data fusion algorithm can achieve a
fine balance between predictive power and time efficiency. We theoretically
guarantee its predictive performance to be equivalent to that of a
sophisticated centralized sparse approximation for the GP model: The
computation of such a sparse approximate GP model can thus be distributed among
the MoD vehicles, hence achieving efficient and scalable demand prediction.
Though our decentralized active sensing strategy is devised to gather the most
informative demand data for demand prediction, it can achieve a dual effect of
fleet rebalancing to service the mobility demands. Empirical evaluation on
real-world mobility demand data shows that our proposed algorithm can achieve a
better balance between predictive accuracy and time efficiency than
state-of-the-art algorithms.


title:
Levy processes: long time behavior and convolution-type form of the Ito
  representation of the infinitesimal generator

abstract:
  In the present paper we show that the Levy-Ito representation of the
infinitesimal generator $L$ for Levy processes $X_t$ can be written in a
convolution-type form. Using the obtained convolution form we have constructed
the quasi-potential operator $B$. We denote by $p(t,\Delta)$ the probability
that a sample of the process $X_t$ remains inside the domain $\Delta$ for
$0{\leq}\tau{\leq}t$ (ruin problem). With the help of the operator $B$ we find
a new formula for $p(t,\Delta)$. This formula allows us to obtain long time
behavior of $p(t,\Delta)$.


title: Extended empirical likelihood for general estimating equations

abstract:
  We derive an extended empirical likelihood for parameters defined by
estimating equations which generalizes the original empirical likelihood for
such parameters to the full parameter space. Under mild conditions, the
extended empirical likelihood has all asymptotic properties of the original
empirical likelihood. Its contours retain the data-driven shape of the latter.
It can also attain the second order accuracy. The first order extended
empirical likelihood is easy-to-use yet it is substantially more accurate than
other empirical likelihoods, including second order ones. We recommend it for
practical applications of the empirical likelihood method.


title:
\delta-doped LaAlO3-SrTiO3 interface: Electrical transport and
  characterization of the interface potential

abstract:
  Here we investigate LaAlO_3-SrTiO_3 heterostructure with\delta-doping of the
interface by LaMnO_3 at less than one monolayer. This doping strongly inhibits
the formation of mobile electron layer at the interface. This results in giant
increase of the resistance and the thermopower of the heterostructure. Several
aspects of this phenomena are investigated. A model to calculate the carrier
concentration is presented and effect of doping and detailed temperature
dependence is analyzed in terms of model parameters and the weak-scattering
theory. The large enhancement of thermopower is attributed to the increased
spin and orbital entropy originating from the LaMnO_3 mono-layer.


title: The Sign Problem, PT Symmetry and Abelian Lattice Duality

abstract:
  Lattice field theories with complex actions are not easily studied using
conventional analytic or simulation methods. However, a large class of these
models are invariant under CT, where C is charge conjugation and T is time
reversal, including models with non-zero chemical potential. For Abelian models
in this class, lattice duality maps models with complex actions into dual
models with real actions. For extended regions of parameter space, calculable
for each model, duality resolves the sign problem for both analytic methods and
computer simulations. Explicit duality relations are given for models for spin
and gauge models based on Z(N) and U(1) symmetry groups. The dual forms are
generalizations of the Z(N) chiral clock model and the lattice
Frenkel-Kontorova model, respectively. From these equivalences, rich sets of
spatially-modulated phases are found in the strong-coupling region of the
original models.


title: Global Residues and Two-Loop Hepta-Cuts

abstract:
  We examine maximal unitarity in the nonplanar case and derive remarkably
compact analytic expressions for coefficients of master integrals with two-loop
crossed box topology in massless four-point amplitudes in any gauge theory,
thereby providing additional steps towards automated computation of the full
amplitude. The coefficients are obtained by assembling residues extracted
through integration on linear combinations of higher-dimensional tori
encircling global poles of the loop integrand. We recover all salient features
of two-loop maximal unitarity, such as the existence of unique projectors for
each master integral. Several explicit calculations are provided. We also
establish exact equivalence of our results and master integral coefficients
recently obtained via integrand-level reduction in any renormalizable gauge
theory.


title: A note on bounded gaps between primes

abstract:
  As a refinement of the celebrated recent work of Yitang Zhang we show that
any admissible k-tuple of integers contains at least two primes and almost
primes in each component infinitely often if k is at least 181000. This implies
that there are infinitely many gaps between consecutive primes of size at most
2530338, with an improved admissible k-tuple of Andrew W. Sutherland to
2326476.


title: Ergodic complex structures on hyperkahler manifolds

abstract:
  Let $M$ be a compact complex manifold. The corresponding Teichmuller space
$\Teich$ is a space of all complex structures on $M$ up to the action of the
group of isotopies. The group $\Gamma$ of connected components of the
diffeomorphism group (known as the mapping class group) acts on $\Teich$ in a
natural way. An ergodic complex structure is the one with a $\Gamma$-orbit
dense in $\Teich$. Let $M$ be a complex torus of complex dimension $\geq 2$ or
a hyperkahler manifold with $b_2>3$. We prove that $M$ is ergodic, unless $M$
has maximal Picard rank (there is a countable number of such $M$). This is used
to show that all hyperkahler manifolds are Kobayashi non-hyperbolic.


title:
Fluctuation analysis and short time asymptotics for multiple scales
  diffusion processes

abstract:
  We consider the limiting behavior of fluctuations of small noise diffusions
with multiple scales around their homogenized deterministic limit. We allow
full dependence of the coefficients on the slow and fast motion. These
processes arise naturally when one is interested in short time asymptotics of
multiple scale diffusions. We do not make periodicity assumptions, but we
impose conditions on the fast motion to guarantee ergodicity. Depending on the
order of interaction between the fast scale and the size of the noise we get
different behavior. In certain cases additional drift terms arise in the
limiting process, which are explicitly characterized. These results provide a
better approximation to the limiting behavior of such processes when compared
to the law of large numbers homogenization limit.


title: A new A4 model for lepton mixing

abstract:
  We present a new model of the lepton sector that uses a family symmetry A4 to
make predictions for lepton mixing which are invariant under any permutation of
the three flavours. We show that those predictions broadly agree with the
experimental data, leading to a largish sin^2(theta12) >~ 0.34, to |cos(delta)|
>~ 0.7, and to | 0.5 - sin^2(theta23) | >~ 0.08; cos(delta) and 0.5 -
sin^2(theta23) are predicted to have identical signs.


title:
Photometric evolution, orbital modulation and progenitor of Nova Mon
  2012

abstract:
  We present and discuss accurate and densely mapped BVRI lightcurves of the
neon Nova Mon 2012, supplemented by the evolution in Stromgren b and y bands
and in the integrated flux of relevant emission lines. Our monitoring started
with the optical discovery of the nova and extend to day +270, well past the
end of the super-soft phase in X-rays. The nova displayed very smoothly
evolving lightcurves. A bifurcation between y and V light-curves took place at
the start of the SSS phase, and a knee developed toward the end of the SSS
phase. The apparent magnitude of the nova at the unobserved optical maximum is
constrained to +2.8=<V=<4.2. The appearance, grow in amplitude and then demise
of a 0.29585 (+/-0.00002) days orbital modulation of the optical brightness was
followed along the nova evolution. The observed modulation has a
near-sinusoidal shape and a weak secondary minimum at phase 0.5. We favor an
interpretation in terms of super-imposed ellipsoidal distortion of the Roche
lobe filling companion and irradiation of its side facing the WD. Similar
lightcurves are typical of symbiotic stars where a Roche lobe filling giant is
irradiated by a very hot WD. Given the high orbital inclination, mutual
occultation between the donor star and the accretion disk could contribute to
the observed modulation. The optical+infrared spectral energy distribution of
Nova Mon 2012 during the quiescence preceeding the outburst is nicely fitted by
a early K-type main-sequence star (~K3V) at 1.5 kpc distance, reddened by
E(B-V)=0.38, with a WD companion and an accretion disk contributing to the
observed blue excess and moderate Halpha emission. A typical early K-type
main-sequence star with a mass of ~0.75 Msun and a radius of ~0.8 Rsun, would
fill its Roche lobe for a P=0.29585 day orbital period and a more massive WD
companion.


title: Phase space flow in the Husimi representation

abstract:
  We derive a continuity equation for the Husimi function evolving under a
general non-hermitian Hamiltonian and identify the phase space flow associated
with it. For the case of unitary evolution we obtain explicit formulas for the
quantum flow, which can be written as a classical part plus semiclassical
corrections. These equations are the analogue of the Wigner flow, which
displays several non-intuitive features like momentum inversion and motion of
stagnation points. Many of these features also appear in the Husimi flow and,
therefore, are not related to the negativity of the Wigner function as
previously suggested. We test the exact and semiclassical formulas for a
particle in a double well potential. We find that the zeros of the Husimi
function are saddle points of the flow, and are always followed by a center.
Merging or splitting of stagnation points, observed in the Wigner flow,does not
occur because of the isolation of the Husimi zeros.


title:
Asymptotic behaviour of first passage time distributions for
  subordinators

abstract:
  In this paper we establish local estimates for the first passage time of a
subordinator under the assumption that it belongs to the Feller class, either
at zero or infinity, having as a particular case the subordinators which are in
the domain of attraction of a stable distribution, either at zero or infinity.
To derive these results we first obtain uniform local estimates for the one
dimensional distribution of such a subordinator, which sharpen those obtained
by Jain and Pruitt in 1987. In the particular case of a subordinator in the
domain of attraction of a stable distribution the results are the analogue of
the results obtained by the authors for non-monotone L\'evy processes. For
subordinators an approach different to that used for non-monotone L\'evy
processes is necessary because the excursion techniques are not available and
also because typically in the non-monotone case the tail distribution of the
first passage time has polynomial decrease, while in the subordinator case it
is exponential.


title:
Phase-Resolved Infrared Spectroscopy and Photometry of V1500 Cygni, and
  a Search for Similar Old Classical Novae

abstract:
  We present phase-resolved near-infrared photometry and spectroscopy of the
classical nova V1500 Cyg to explore whether cyclotron emission is present in
this system. While the spectroscopy do not indicate the presence of discrete
cyclotron harmonic emission, the light curves suggest that a sizable fraction
of its near-infrared fluxes are due to this component. The light curves of
V1500 Cyg appear to remain dominated by emission from the heated face of the
secondary star in this system. We have used infrared spectroscopy and
photometry to search for other potential magnetic systems amongst old classical
novae. We have found that the infrared light curves of V1974 Cyg superficially
resemble those of V1500 Cyg, suggesting a highly irradiated companion. The old
novae V446 Her and QV Vul have light curves with large amplitude variations
like those seen in polars, suggesting they might have magnetic primaries. We
extract photometry for seventy nine old novae from the 2MASS Point Source
Catalog and use those data to derive the mean, un-reddened infrared colors of
quiescent novae. We also extract WISE data for these objects and find that
forty five of them were detected. Surprisingly, a number of these systems were
detected in the WISE 22 mum band. While two of those objects produced
significant dust shells (V705 Cas and V445 Pup), the others did not. It appears
that line emission from their ionized ejected shells is the most likely
explanation for those detections.


title:
On the Basis Property of the Root Functions of Sturm-Liouville Operators
  with General Regular Boundary Conditions

abstract:
  We obtain the asymptotic formulas for the eigenvalues and eigenfunctions of
the Sturm-Liouville operators with general regular boundary conditions. Using
these formulas, we find sufficient conditions on the potential q such that the
root functions of these operators do not form a Riesz basis.


title: Torsion in one-term distributive homology

abstract:
  The one-term distributive homology was introduced by J.H.Przytycki as an
atomic replacement of rack and quandle homology, which was first introduced and
developed by R.Fenn, C.Rourke and B.Sanderson, and J.S.Carter, S.Kamada and
M.Saito. This homology was initially suspected to be torsion-free, but we show
in this paper that the one-term homology of a finite spindle can have torsion.
We carefully analyze spindles of block decomposition of type (n,1) and
introduce various techniques to compute their homology precisely. In addition,
we show that any finite group can appear as the torsion subgroup of the first
homology of some finite spindle. Finally, we show that if a shelf satisfies a
certain, rather general, condition then the one-term homology is trivial.


title: Molecular gas in type 2 quasars at z~0.2-0.3

abstract:
  We present results of CO(1-0) spectroscopic observations of 10 SDSS type 2
quasars (QSO2) at z~0.2-0.3 observed with the 30m IRAM radiotelescope and the
Australia Telescope Compact Array. We report 5 new confirmed CO(1-0) detections
and 1 tentative detection. They have L'(CO)~several x 1e9 K km s-1 pc^2, while
upper limits for the non detections are L'(CO)<~ several x 1e9 K km s-1 pc^2.
This study increases the total number of QSO2 with CO measurements at z<~1 to
20, with a 50% detection rate.


title:
The Polya branching process and limit theorems for conditioned random
  fields

abstract:
  The first aim is to construct generalizations of Polya type point process by
applying a branching mechanism to these point processes. Conditions are given
under which these point processes satisfy an integration by parts formula.
Furthermore we compute their Palm kernels, which turn out to be superpositions
of different point processes. Secondly we identify all point processes whose
local characteristics agree with these of a fixed branching of a Polya type
point process as mixtures of branchings of Polya type point process and show
that in this case also they are characterized by an integration by parts
formula.


title:
Characterisation of the muon beams for the Muon Ionisation Cooling
  Experiment

abstract:
  A novel single-particle technique to measure emittance has been developed and
used to characterise seventeen different muon beams for the Muon Ionisation
Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to
281 MeV/c, have emittances of approximately 1.5--2.3 \pi mm-rad horizontally
and 0.6--1.0 \pi mm-rad vertically, a horizontal dispersion of 90--190 mm and
momentum spreads of about 25 MeV/c. There is reasonable agreement between the
measured parameters of the beams and the results of simulations. The beams are
found to meet the requirements of MICE.


title:
The logical postulates of B\"oge, Carnap and Johnson in the context of
  Papangelou processes

abstract:
  We adapt Johnson's sufficiency postulate, Carnap's prediction invariance
postulate and B\"oge's learn-merge invariance to the context of Papangelou
processes and discuss equivalence of their generalizations, in particular their
weak and strong generalizations. This discussion identifies a condition which
occurs in the construction of Papangelou processes. In particular, we show that
these generalizations characterize classes of Poisson and P\'olya point
processes.


title:
SPATA: A Seeding and Patching Algorithm for Hybrid Transcriptome
  Assembly

abstract:
  Transcriptome assembly from RNA-Seq reads is an active area of bioinformatics
research. The ever-declining cost and the increasing depth of RNA-Seq have
provided unprecedented opportunities to better identify expressed transcripts.
However, the nonlinear transcript structures and the ultra-high throughput of
RNA-Seq reads pose significant algorithmic and computational challenges to the
existing transcriptome assembly approaches, either reference-guided or de novo.
While reference-guided approaches offer good sensitivity, they rely on
alignment results of the splice-aware aligners and are thus unsuitable for
species with incomplete reference genomes. In contrast, de novo approaches do
not depend on the reference genome but face a computational daunting task
derived from the complexity of the graph built for the whole transcriptome. In
response to these challenges, we present a hybrid approach to exploit an
incomplete reference genome without relying on splice-aware aligners. We have
designed a split-and-align procedure to efficiently localize the reads to
individual genomic loci, which is followed by an accurate de novo assembly to
assemble reads falling into each locus. Using extensive simulation data, we
demonstrate a high accuracy and precision in transcriptome reconstruction by
comparing to selected transcriptome assembly tools. Our method is implemented
in assemblySAM, a GUI software freely available at
http://sammate.sourceforge.net.


title:
Evidence for temperature dependent spin-diffusion as a mechanism of
  intrinsic flux noise in SQUIDs

abstract:
  The intrinsic flux noise observed in superconducting quantum interference
devices (SQUIDs) is thought to be due to the fluctuation of electron spin
impurities, but the frequency and temperature dependence observed in
experiments do not agree with the usual 1/f models. We present theoretical
calculations and experimental measurements of flux noise in rf-SQUID flux
qubits that show how these observations, and previous reported measurements,
can be interpreted in terms of a spin-diffusion constant that increases with
temperature. We fit measurements of flux noise in sixteen devices, taken in the
20-80 mK temperature range, to the spin-diffusion model. This allowed us to
extract the spin-diffusion constant and its temperature dependence, suggesting
that the spin system is close to a spin-glass phase transition.


title: Analytic equivalence relations satisfying hyperarithmetic-is-recursive

abstract:
  We prove, in ZF+$\bf\Sigma^1_2$-determinacy, that for any analytic
equivalence relation $E$, the following three statements are equivalent: (1)
$E$ does not have perfectly many classes, (2) $E$ satisfies
hyperarithmetic-is-recursive on a cone, and (3) relative to some oracle, for
every equivalence class $[Y]_E$ we have that a real $X$ computes a member of
the equivalence class if and only if $\om_1^X\geq\om_1^{[Y]}$.
  We also show that the implication from (1) to (2) is equivalent to the
existence of sharps over $ZF$.


title: Infinitesimal Hecke algebras of so_N

abstract:
  In this article we classify all infinitesimal Hecke algebras of so_N. We
establish isomorphism of their universal versions and the W-algebras of
so_{N+2m+1} with a 1-block nilpotent element of the Jordan type (1,...,1,2m+1).
This should be considered as a continuation of the recent joint paper with I.
Losev, where the analogous results were obtained for the cases of gl_n and
sp_{2n}.


title: The Hodge conjecture and arithmetic quotients of complex balls

abstract:
  Let $S$ be a closed Shimura variety uniformized by the complex $n$-ball. The
Hodge conjecture predicts that every Hodge class in $H^{2k} (S, \Q)$, $k=0,
\ldots, n$, is algebraic. We show that this holds for all degree $k$ away from
the neighborhood $]n/3, 2n/3[$ of the middle degree. We also address the Tate
conjecture and the generalized form of the Hodge conjecture and extend most of
our results to Shimura varieties associated to unitary groups of any signature.
The proofs make use of the recent endoscopic classification of automorphic
representations of classical groups by \cite{ArthurBook,Mok}. As such our
results are conditional on the stabilization of the trace formula for the
(disconnected) groups $\GL (N) \rtimes \langle \theta \rangle$ associated to
base change. Unfortunately, at present the stabilization of the trace formula
has been proved only for the case of {\it connected} groups. The extension
needed is part of work in progress by the Paris-Marseille team of automorphic
form researchers. For more detail, see the second paragraph of subsection
\ref{org2} below.


title: The Gopakumar-Vafa formula for symplectic manifolds

abstract:
  The Gopakumar-Vafa conjecture predicts that the Gromov-Witten invariants of a
Calabi-Yau 3-fold can be canonically expressed in terms of integer invariants
called BPS numbers. Using the methods of symplectic Gromov-Witten theory, we
prove that the Gopakumar-Vafa formula holds for any symplectic Calabi-Yau
6-manifold, and hence for Calabi-Yau 3-folds. The results extend to all
symplectic 6-manifolds and to the genus zero GW invariants of semipositive
manifolds.


title:
Mimic the optical conductivity in disordered solids via gauge/gravity
  duality

abstract:
  We study the optical conductivity in a (2+1)-dimensional non-relativistic
field theory holographically dual to a (3+1)-dimensional charged Lifshitz black
brane with the Einstein-Maxwell-dilaton theory. Surprisingly, we find that the
optical AC conductivity satisfies the nontrivial (non-)power law scaling in the
high frequency regime rather than approaching to a constant when the dynamical
critical exponent $z>1$, which is qualitatively similar to those in various
disordered solids in condensed matter systems. Besides, this (non-)power law
scaling behavior shows some universality, which is robust against the
temperatures. We argue that the peculiar scaling behavior of AC conductivity
may stem from the couplings of the dilaton field with the gauge fields and also
the logarithmic behavior near the boundary in the Lifshitz spacetime.


title:
Contamination of Broad-Band Photometry by Nebular Emission in High
  Redshift Galaxies: Investigations with Keck's MOSFIRE Near-Infrared
  Spectrograph

abstract:
  Earlier work has raised the potential importance of nebular emission in the
derivation of the physical characteristics of high redshift Lyman break
galaxies. Within certain redshift ranges, and especially at z ~ 6-7, such lines
may be strong enough to reduce estimates of the stellar masses and ages of
galaxies compared those derived assuming broad-band photometry represents
stellar light alone. To test this hypothesis at the highest redshifts where
such lines can be probed with ground-based facilities, we examine the
near-infrared spectra of a representative sample of 20 3.0 < z < 3.8 Lyman
break galaxies using the newly-commissioned MOSFIRE near-infrared spectrograph
at the Keck I telescope. We use this data to derive the rest-frame equivalent
widths (EW) of [O III] emission and show that these are comparable to estimates
derived using the SED fitting technique introduced for sources of known
redshift by Stark et al (2013). Although our current sample is modest, its [O
III] EW distribution is consistent with that inferred for H\alpha\ based on SED
fitting of Stark et al's larger sample of 3.8 < z < 5 galaxies. For a subset of
survey galaxies, we use the combination of optical and near-infrared
spectroscopy to quantify kinematics of outflows in z ~ 3.5 star-forming
galaxies, and discuss the implications for reionization measurements. The
trends we uncover underline the dangers of relying purely on broad-band
photometry to estimate the physical properties of high redshift galaxies and
emphasize the important role of diagnostic spectroscopy.


title: Lattice Gas Symmetric Cryptography

abstract:
  Lattice gas cellular automata (Lgca) are particular cellular automata that
imitate the behavior of par- ticles moving on a lattice. We used a particular
set of Lgca rules, called hpp, to mix bits in data blocks and obtain a
symmetric cryptographic algorithm. The encryption and decryption keys are the
positions of perturbation sites on the lattice (walls). Basically, this paper
presents an original way to perform cryp- tographic operations, based on
cellular automata. In this paper, we show several characteristics about our
algorithm: typical block size (2^(2n-1) ), key-length (2^n ), number of rounds
(2^(n+1) ). We also evaluate avalanche and strict avalanche properties with
respect to key and plain text. Finally, we highlight the underbellies of our
method and give clues to solve them.


title: Policy Search: Any Local Optimum Enjoys a Global Performance Guarantee

abstract:
  Local Policy Search is a popular reinforcement learning approach for handling
large state spaces. Formally, it searches locally in a paramet erized policy
space in order to maximize the associated value function averaged over some
predefined distribution. It is probably commonly b elieved that the best one
can hope in general from such an approach is to get a local optimum of this
criterion. In this article, we show th e following surprising result:
\emph{any} (approximate) \emph{local optimum} enjoys a \emph{global performance
guarantee}. We compare this g uarantee with the one that is satisfied by Direct
Policy Iteration, an approximate dynamic programming algorithm that does some
form of Poli cy Search: if the approximation error of Local Policy Search may
generally be bigger (because local search requires to consider a space of s
tochastic policies), we argue that the concentrability coefficient that appears
in the performance bound is much nicer. Finally, we discuss several practical
and theoretical consequences of our analysis.


title: Hecke-type congruences for Andrews' spt-function modulo 16 and 32

abstract:
  Inspired by recent congruences by Andersen with varying powers of 2 in the
modulus for partition related functions, we extend the modulo 32760 congruences
of the first author for the function spt(n). We show that a normalized form of
the generating function of spt(n) is an eigenform modulo 32 for the Hecke
operators T(l^2) for primes l >= 5 with l congruent to 1, 11, 17, 19 (mod 24),
and an eigenform modulo 16 for l congruent to? 13, 23 (mod 24).


title: Remarks on correlators of Polyakov Loops

abstract:
  Polyakov loop eigenvalues and their N-dependence are studied in 2 and 4
dimensional SU(N) YM theory. The connected correlation function of the single
eigenvalue distributions of two separated Polyakov loops in 2D YM is calculated
and is found to have a structure differing from the one of corresponding
hermitian random matrix ensembles. No large $N$ non-analyticities are found for
two point functions in the confining regime. Suggestions are made for
situations in which large-N phase transitions involving Polyakov loops might
occur.


title:
Extended Conformal Symmetry and Recursion Formulae for Nekrasov
  Partition Function

abstract:
  We derive an infinite set of recursion formulae for Nekrasov instanton
partition function for linear quiver U(N) supersymmetric gauge theories in 4D.
They have a structure of a deformed version of W_{1+\infty} algebra which is
called SH^c algebra (or degenerate double affine Hecke algebra) in the
literature. The algebra contains W_N algebra with general central charge
defined by a parameter \beta, which gives the $\Omega$ background in Nekrasov's
analysis. Some parts of the formulae are identified with the conformal Ward
identity for the conformal block function of Toda field theory.


title: Lower bounds on the norms of extension operators for Lipschitz domains

abstract:
  Let $\Omega\subset\dR^d$ be a bounded or an unbounded Lipschitz domain. In
this note we address the problem of continuation of functions from the Sobolev
space $H^1(\Omega)$ up to functions in the Sobolev space $H^1(\dR^d)$ via a
linear operator. The minimal possible norm of such an operator is estimated
from below in terms of spectral properties of self-adjoint Robin Laplacians on
domains $\Omega$ and $\dR^d\setminus\ov\Omega$. Another estimate of this norm
is also given, where spectral properties of Schr\"odinger operators with the
$\delta$-interaction supported on the hypersurface $\partial\Omega$ are
involved. General results are illustrated with examples.


title: Leptons in Composite MFV

abstract:
  We study the lepton sector of composite Higgs models with partial
compositeness. The standard anarchic scenario is in conflict with the absence
of observable charged lepton flavor violation. This tension can be completely
solved in MFV scenarios that require either left-handed or right-handed SM
leptons to be equally composite. Constraints on this scenario are weak and the
composite lepton partners could be as light as few hundreds GeVs with
interesting LHC signatures. The contribution to the muon (g-2) in theories
where the Higgs is a pseudo Nambu-Goldstone boson is also discussed.


title: Low-dimensional chaos in RR Lyrae models

abstract:
  The recent precise photometric observations and successes of the modelling
efforts transformed our picture of the pulsation of RR Lyrae stars. The
discovery of additional frequencies and the period doubling phenomenon revealed
that a significant interaction may occur between pulsational modes. The signs
of irregularities were detected both in observed light curves and hydrodynamic
calculations.
  In this paper we present the analysis of four peculiar hydrodynamic model
solutions. All four solutions were found to be chaotic. The fractal (Lyapunov)
dimensions of their attractors were calculated to be ~2.2. We also investigated
possible resonances between the fundamental mode and the first overtone in the
dynamical neighbourhood of these models. The most important is the 6:8
resonance that was also detected in the Kepler observations of RR Lyrae itself.
These results reveal that the investigation of chaotic models is important in
discovering and understanding resonances in RR Lyrae stars.


title: Cosmological constant and vacuum energy: old and new ideas

abstract:
  The cosmological constant (CC) term in Einstein's equations, Lambda, was
first associated to the idea of vacuum energy density. Notwithstanding, it is
well-known that there is a huge, in fact appalling, discrepancy between the
theoretical prediction and the observed value picked from the modern
cosmological data. This is the famous, and extremely difficult, "CC problem".
Paradoxically, the recent observation at the CERN Large Hadron Collider of a
Higgs-like particle, should actually be considered ambivalent: on the one hand
it appears as a likely great triumph of particle physics, but on the other hand
it wide opens Pandora's box of the cosmological uproar, for it may provide
(alas!) the experimental certification of the existence of the electroweak (EW)
vacuum energy, and thus of the intriguing reality of the CC problem. Even if
only counting on this contribution to the inventory of vacuum energies in the
universe, the discrepancy with the cosmologically observed value is already of
55 orders of magnitude. This is the (hitherto) "real" magnitude of the CC
problem, rather than the (too often) brandished 123 ones from the upper (but
fully unexplored!) ultrahigh energy scales. Such is the baffling situation
after 96 years of introducing the Lambda-term by Einstein. In the following I
will briefly (and hopefully pedagogically) fly over some of the old and new
ideas on the CC problem. Since, however, the Higgs boson just knocked our door
and recalled us that the vacuum energy may be a fully tangible concept in real
phenomenology, I will exclusively address the CC problem from the original
notion of vacuum energy, and its possible "running" with the expansion of the
universe, rather than venturing into the numberless attempts to replace the CC
by the multifarious concept of dark energy.


title:
Superconductivity with intrinsic topological order induced by pure
  Coulomb interaction and time-reversal symmetry breaking

abstract:
  Recently, in certain flat band lattice systems at commensurate fillings,
fractional quantum Hall states have been found -- which have anyonic
excitations. We study such systems away from commensuration, i.e. the ground
state of an anyon gas in such a system. The presence of the underlying lattice
allows access to an entirely new regime where the anyon kinetic energy can be
larger than their interaction energy. Within the flux-attachment approach,
using mean-field then adding fluctuations, we find several possible superfluid
states. Two have intrinsic topological order, i.e. fractionalized
quasiparticles with a fusion structure of (Z_2)^4 and (Z_8)^2 respectively, and
a third has no fractionalized excitations similar to a BCS-type state. This
represents a mechanism for superconductivity driven purely by strong repulsion
and complex hopping of electrons.


title:
Scaling Properties of Rainfall-Induced Landslides Predicted by a
  Physically Based Model

abstract:
  Natural landslides exhibit scaling properties revealed by power law
relationships. These relationships include the frequency of the size (e.g.,
area, volume) of the landslides, and the rainfall conditions responsible for
slope failures in a region. Reasons for the scaling behavior of landslides are
poorly known. We investigate the possibility of using the Transient Rainfall
Infiltration and Grid-Based Regional Slope-Stability analysis code (TRIGRS), a
consolidated, physically-based, numerical model that describes the
stability/instability conditions of natural slopes forced by rainfall, to
determine the frequency statistics of the area of the unstable slopes and the
rainfall intensity (I) - duration (D) conditions that result in landslides in a
region. We apply TRIGRS in a portion of the Upper Tiber River Basin, Central
Italy. The spatially distributed model predicts the stability/instability
conditions of individual grid cells, given the local terrain and rainfall
conditions. We run TRIGRS using multiple, synthetic rainfall histories, and we
compare the modeling results with empirical evidences of the area of landslides
and of the rainfall conditions that have caused landslides in the study area.
Our findings revealed that TRIGRS is capable of reproducing the frequency of
the size of the patches of terrain predicted as unstable by the model, which
match the frequency size statistics of landslides in the study area, and the
mean rainfall D, I conditions that result in unstable slopes in the study area,
which match rainfall I-D thresholds for possible landslide occurrence. Our
results are a step towards understanding the mechanisms that give rise to
landslide scaling properties.


title:
The Hunt for Exomoons with Kepler (HEK): III. The First Search for an
  Exomoon around a Habitable-Zone Planet

abstract:
  Kepler-22b is the first transiting planet to have been detected in the
habitable-zone of its host star. At 2.4 Earth radii, Kepler-22b is too large to
be considered an Earth-analog, but should the planet host a moon large enough
to maintain an atmosphere, then the Kepler-22 system may yet possess a telluric
world. Aside from being within the habitable-zone, the target is attractive due
to the availability of previously measured precise radial velocities and low
intrinsic photometric noise, which has also enabled asteroseismology studies of
the star. For these reasons, Kepler-22b was selected as a target-of-opportunity
by the 'Hunt for Exomoons with Kepler' (HEK) project. In this work, we conduct
a photodynamical search for an exomoon around Kepler-22b leveraging the
transits, radial velocities and asteroseismology plus several new tools
developed by the HEK project to improve exomoon searches. We find no evidence
for an exomoon around the planet and exclude moons of mass >0.5 Earth masses to
95% confidence. By signal injection and blind retrieval, we demonstrate that an
Earth-like moon is easily detected for this planet even when the
time-correlated noise of the data set is taken into account. We provide updated
parameters for the planet Kepler-22b including a revised mass of <53 Earth
masses to 95% confidence and an eccentricity of 0.13(-0.13)(+0.36) by
exploiting Single-body Asterodensity Profiling (SAP). Finally, we show that
Kepler-22b has a >95% probability of being within the empirical habitable-zone
but a <5% probability of being within the conservative habitable-zone.


title: Implications of the Anomalous Outburst in the Blazar PKS 0208-512

abstract:
  The flat spectrum radio quasar (FSRQ) PKS 0208-512 underwent three outbursts
at the optical-near-infrared (OIR) wavelengths during 2008-2011. The second OIR
outburst did not have a gamma-ray counterpart despite being comparable in
brightness and temporal extent to the other two. We model the time variable
spectral energy distribution of PKS 0208-512 during those three flaring
episodes with leptonic models to investigate the physical mechanism that can
produce this anomalous flare. We show that the redder-when-brighter spectral
trend in the OIR bands can be explained by the superposition of a fixed thermal
component from the accretion disk and a synchrotron component of fixed shape
and variable normalization. We estimate the accretion disk luminosity at L_d ~8
X 10^45 erg/s. Using the observed variability timescale in the OIR band
t_{var,obs} ~2 d and the X-ray luminosity L_X ~3.5 X 10^45 erg/s, we constrain
the location of the emitting region to distance scales that are broadly
comparable with the dusty torus. We show that variations in the Compton
dominance parameter by a factor of ~4 --- which may result in the anomalous
outburst --- can be relatively easily accounted for by moderate variations in
the magnetic field strength or the location of the emission region. Since such
variations appear to be rare among FSRQs, we propose that most gamma-ray/OIR
flares in these objects are produced in jet regions where the magnetic field
and external photon fields vary similarly with distance along the jet, e.g.,
u_B ~u_ext ~r^{-2}.


title: Crystalline Scaling Geometries from Vortex Lattices

abstract:
  We study magnetic geometries with Lifshitz and/or hyperscaling violation
exponents (both with a hard wall cutoff in the IR and a smooth black brane
horizon) which have a complex scalar field which couples to the magnetic field.
The complex scalar is unstable to the production of a vortex lattice in the IR.
The lattice is a normalizable mode which is relevant (i.e. grows into the IR.)
When one considers linearized backreaction of the lattice on the metric and
gauge field, the metric forms a crystalline structure. We analyze the scaling
of the free energy, thermodynamic entropy, and entanglement in the lattice
phase and find that in the smeared limit, the leading order correction to
thermodynamic properties due to the lattice has the scaling behavior of a
theory with a hyperscaling violation exponent between 0 and 1, indicating a
flow to an effectively lower-dimensional theory in the deep IR.


title:
LyMAS: Predicting Large-Scale Lyman-alpha Forest Statistics from the
  Dark Matter Density Field

abstract:
  [abridged] We describe LyMAS (Ly-alpha Mass Association Scheme), a method of
predicting clustering statistics in the Ly-alpha forest on large scales from
moderate resolution simulations of the dark matter distribution, with
calibration from high-resolution hydrodynamic simulations of smaller volumes.
We use the "Horizon MareNostrum" simulation, a 50 Mpc/h comoving volume evolved
with the adaptive mesh hydrodynamic code RAMSES, to compute the conditional
probability distribution P(F_s|delta_s) of the transmitted flux F_s, smoothed
(1-dimensionally) over the spectral resolution scale, on the dark matter
density contrast delta_s, smoothed (3-dimensionally) over a similar scale. In
this study we adopt the spectral resolution of the SDSS-III BOSS at z=2.5, and
we find optimal results for a dark matter smoothing length sigma=0.3 Mpc/h
(comoving). In extended form, LyMAS exactly reproduces both the 1-dimensional
power spectrum and 1-point flux distribution of the hydro simulation spectra.
Applied to the MareNostrum dark matter field, LyMAS accurately predicts the
2-point conditional flux distribution and flux correlation function of the full
hydro simulation for transverse sightline separations as small as 1 Mpc/h,
including redshift-space distortion effects. It is substantially more accurate
than a deterministic density-flux mapping ("Fluctuating Gunn-Peterson
Approximation"), often used for large volume simulations of the forest. With
the MareNostrum calibration, we apply LyMAS to 1024^3 N-body simulations of a
300 Mpc/h and 1.0 Gpc/h cube to produce large, publicly available catalogs of
mock BOSS spectra that probe a large comoving volume. LyMAS will be a powerful
tool for interpreting 3-d Ly-alpha forest data, thereby transforming
measurements from BOSS and other massive quasar absorption surveys into
constraints on dark energy, dark matter, space geometry, and IGM physics.


title: Is Natural SUSY Natural?

abstract:
  We study the fine tuning associated to a `Natural Supersymmetry' spectrum
with stops, after RG running, significantly lighter than the first two
generation sfermions and the gluino. In particular, we emphasise that this
tuning should be measured with respect to the parameters taken to be
independent at the assumed UV boundary of the renormalisation group flow, and
improve the accuracy of previous approximate expressions. It is found that, if
running begins at $10^{16}~\rm{GeV}$ $\left(10^5~\rm{GeV}\right)$, decreasing
the UV stop mass below $0.75$ $\left(0.4\right)$ of the weak scale Majorana
gluino mass does not improve the overall fine tuning of the theory. In
contrast, it is possible to raise the first two generation sfermion masses out
of LHC reach without introducing additional tuning. After running, regions of
parameter space favoured by naturalness and consistent with LHC bounds
typically have IR stop masses of order 1.5 TeV (0.75 TeV), and fine tuning of
at least 400 (50) for high (low) scale mediation. We also study the fine tuning
of theories with Dirac gluinos. These allow for substantial separation of the
gluino and sfermion masses and, regardless of the scale of mediation, lead to
relatively low fine tuning of order 50. Hence viable models can still favour
light stops, but this requires extra structure beyond the MSSM field content.


title: Narrowband Lyman-Continuum Imaging of Galaxies at z ~ 2.85

abstract:
  We present results from a survey for z~2.85 Lyman-Continuum (LyC) emission in
the HS1549+1933 field and place constraints on the amount of ionizing radiation
escaping from star-forming galaxies. Using a custom narrowband filter (NB3420)
tuned to wavelengths just below the Lyman limit at z>=2.82, we probe the LyC
spectral region of 49 Lyman break galaxies (LBGs) and 91 Lya-emitters (LAEs)
spectroscopically confirmed at z>=2.82. Four LBGs and seven LAEs are detected
in NB3420. Using V-band data probing the rest-frame non-ionizing UV, we observe
that many NB3420-detected galaxies exhibit spatial offsets between their LyC
and non-ionizing UV emission and are characterized by extremely blue NB3420-V
colors, corresponding to low ratios of non-ionizing to ionizing radiation
(F_UV/F_LyC) that are in tension with current stellar population synthesis
models. We measure average values of F_UV/F_LyC for our LBG and LAE samples,
correcting for foreground galaxy contamination and HI absorption in the IGM. We
find (F_UV/F_LyC)_corr^LBG=82 +/- 45 and (F_UV/F_LyC)_corr^LAE=7.4 +/- 3.6.
These flux-density ratios correspond respectively to relative LyC escape
fractions of f_esc,rel^LBG=5-8% and f_esc,rel^LAE=18-49%, absolute LyC escape
fractions of f_esc^LBG=1-2% and f_esc^LAE=5-15%, and a comoving LyC emissivity
from star-forming galaxies of 8.8-15.0 x 10^24 ergs/s/Hz/Mpc^3. In order to
study the differential properties of galaxies with and without LyC detections,
we analyze narrowband Lya imaging and rest-frame near-infrared imaging, finding
that while LAEs with LyC detections have lower Lya equivalent widths on
average, there is no substantial difference in the rest-frame near-infrared
colors of LBGs or LAEs with and without LyC detections. These preliminary
results are consistent with an orientation-dependent model where LyC emission
escapes through cleared paths in a patchy ISM.


title: Limits on Neutrino-Neutrino Scattering in the Early Universe

abstract:
  In the standard model neutrinos are assumed to have streamed across the
Universe since they last scattered at the weak decoupling epoch when the
temperature of the standard-model plasma was ~MeV. The shear stress of
free-streaming neutrinos imprints itself gravitationally on the Cosmic
Microwave Background (CMB) and makes the CMB a sensitive probe of neutrino
scattering. Yet, the presence of nonstandard physics in the neutrino sector may
alter this standard chronology and delay neutrino free-streaming until a much
later epoch. We use observations of the CMB to constrain the strength of
neutrino self-interactions G_eff and put limits on new physics in the neutrino
sector from the early Universe. Recent measurements of the CMB at large
multipoles made by the Planck satellite and high-l experiments are critical for
probing this physics. Within the context of conventional LambdaCDM parameters
cosmological data are compatible with G_eff < 1/(56 MeV)^2 and neutrino
free-streaming might be delayed until their temperature has cooled to as low as
~25 eV. Intriguingly, we also find an alternative cosmology compatible with
cosmological data in which neutrinos scatter off each other until z~10^4 with a
preferred interaction strength in a narrow region around $G_{\rm eff} \simeq
1/({\rm 10 \, MeV})^{2} \simeq 8.6\times10^8 G_{\rm F}$, where $G_{\rm F}$ is
the Fermi constant. This distinct self-interacting neutrino cosmology is
characterized by somewhat lower values of both the scalar spectral index and
the amplitude of primordial fluctuations. While we phrase our discussion here
in terms of a specific scenario in which a late onset of neutrino
free-streaming could occur, our constraints on the neutrino visibility function
are very general.


title:
Top-quark pair production at high invariant mass: an NNLO soft plus
  virtual approximation

abstract:
  We obtain a soft plus virtual approximation to the NNLO QCD contributions to
the top-pair invariant mass distribution at hadron colliders. It is valid up to
corrections of order m_t^2/M^2, with M the pair invariant mass. This is
currently the most complete QCD calculation for a differential cross section in
top-quark pair production, and is useful for describing the high invariant mass
region characteristic of boosted top quarks. We use our results to construct an
improved NNLO approximation for the pair invariant mass distribution and
compare it with previous, less complete approximations based on logarithmic
terms from NNLL soft-gluon resummation alone. We find that the new NNLO
approximation produces moderate enhancements of the differential cross section
compared to previous ones, the effect being slightly more important at low
values of invariant mass than at high ones. On the other hand, at high values
of invariant mass the new NNLO corrections are dominated by even higher-order
effects included in NNLL soft-gluon resummation, reaffirming the need for
resummation in describing the highly boosted regime.


title:
Unconventional Fusion and Braiding of Topological Defects in a Lattice
  Model

abstract:
  We demonstrate the semiclassical nature of symmetry twist defects that differ
from quantum deconfined anyons in a true topological phase by examining
non-abelian crystalline defects in an abelian lattice model. An underlying
non-dynamical ungauged S3-symmetry labels the quasi-extensive defects by group
elements and gives rise to order dependent fusion. A central subgroup of local
Wilson observables distinguishes defect-anyon composites by species, which can
mutate through abelian anyon tunneling by tuning local defect phase parameters.
We compute a complete consistent set of primitive basis transformations, or
F-symbols, and study braiding and exchange between commuting defects. This
suggests a modified spin-statistics theorem for defects and non-modular group
structures unitarily represented by the braiding S and exchange T matrices.
Non-abelian braiding operations in a closed system represent the sphere braid
group projectively by a non-trivial central extension that relates the
underlying symmetry.


title: Detection and Manipulation of Majorana Fermions in Circuit QED

abstract:
  Motivated by recent experimental progress towards the measurement and
manipulation of Majorana fermions with superconducting circuits, we propose a
device interfacing Majorana fermions with circuit quantum electrodynamics. The
proposed circuit acts as a charge parity detector changing the resonance
frequency of a superconducting $\lambda/4$ - resonator conditioned on the
parity of charges on nearby gates. Operating at both charge and flux sweet
spots, this device is highly insensitive to environmental noise. It enables
high-fidelity single-shot quantum non demolition readout of the state of a pair
of Majorana fermions encoding a topologically protected qubit. Additionally,
the interaction permits the realization of an arbitrary phase gate on the
topological qubit, closing the loop for computational completeness. Away from
the charge sweet spot, this device can be used as a highly sensitive charge
detector with a sensitivity better than $10^{-4} \text{e} / \sqrt{\text{Hz}}$
and bandwidth larger than $1$ MHz.


title: All Off-Shell R^2 Invariants in Five Dimensional N=2 Supergravity

abstract:
  We construct supersymmetric completions of various curvature squared terms in
five dimensional supergravity with eight supercharges. Adopting the dilaton
Weyl multiplet, we obtain the minimal off-shell supersymmetric Ricci scalar
squared as well as all vector multiplets coupled curvature squared invariants.
Since the minimal off-shell supersymmetric Riemann tensor squared and
Gauss-Bonnet combination in the dilaton Weyl multiplet have been obtained
before, both the minimal off-shell and the vector multiplets coupled curvature
squared invariants in the dilation Weyl multiplet are complete. We also
constructed an off-shell Ricci scalar squared invariant utilizing the standard
Weyl multiplet. The supersymmetric Ricci scalar squared in the standard Weyl
multiplet is coupled to n number of vector multiplets by construction, and it
deforms the very special geometry. We found that in the supersymmetric AdS_5
vacuum, the very special geometry defined on the moduli space is modified in a
simple way. Finally, we study the magnetic string and electric black hole
solutions in the presence of supersymmetric Ricci scalar squared.


title:
The Grunewald-O'Halloran conjecture for nilpotent Lie algebras of rank
  >= 1

abstract:
  Grunewald and O'Halloran conjectured in 1993 that every complex nilpotent Lie
algebra is the degeneration of another, non isomorphic, Lie algebra. We prove
the conjecture for the class of nilpotent Lie algebras admitting a semisimple
derivation, remaining open for the class of characteristically nilpotent Lie
algebras. In dimension 7, where the first characteristically nilpotent Lie
algebras appear, we prove the conjecture and we also exhibit explicit
nontrivial degenerations to every 7-dimensional nilpotent Lie algebra.


title: Bounded cohomology with coefficients in uniformly convex Banach spaces

abstract:
  We show that for acylindrically hyperbolic groups $\Gamma$ (with no
nontrivial finite normal subgroups) and arbitrary unitary representation $\rho$
of $\Gamma$ in a (nonzero) uniformly convex Banach space the vector space
$H^2_b(\Gamma;\rho)$ is infinite dimensional. The result was known for the
regular representations on $\ell^p(\Gamma)$ with $1<p<\infty$ by a different
argument. But our result is new even for a non-abelian free group in this great
generality for representations, and also the case for acylindrically hyperbolic
groups follows as an application.


title: S-duality and the N=2 Lens Space Index

abstract:
  We discuss some of the analytic properties of lens space indices for 4d N=2
theories of class S. The S-duality properties of these theories highly
constrain the lens space indices, and imply in particular that they are
naturally acted upon by a set of commuting difference operators corresponding
to surface defects. We explicitly identify the difference operators to be a
matrix-valued generalization of the elliptic Ruijsenaars-Schneider model. In a
special limit these difference operators can be expressed naturally in terms of
Cherednik operators appearing in the double affine Hecke algebras, with the
eigenfunctions given by non-symmetric Macdonald polynomials.


title: A quantitative study of source imaging in random waveguides

abstract:
  We present a quantitative study of coherent array imaging of remote sources
in randomly perturbed waveguides with bounded cross-section. We study how long
range cumulative scattering by perturbations of the boundary and the medium
impedes the imaging process. We show that boundary scattering effects can be
mitigated with filters that enhance the coherent part of the data. The filters
are obtained by optimizing a measure of quality of the image. The point is that
there is an optimal trade-off between the robustness and resolution of images
in such waveguides, which can be found adaptively, as the data are processed to
form the image. Long range scattering by perturbations of the medium is harder
to mitigate than scattering by randomly perturbed boundaries. Coherent imaging
methods do not work and more complex incoherent methods, based on transport
models of energy, should be used instead. Such methods are nor useful, nor
needed in waveguides with perturbed boundaries. We explain all these facts
using rigorous asymptotic stochastic analysis of the wave field in randomly
perturbed waveguides. We also analyze the adaptive coherent imaging method and
obtain a quantitative agreement with the results of numerical simulations.


title:
Few-Particle Vortex Cluster Equilibria in Bose-Einstein Condensates:
  Existence and Stability

abstract:
  Motivated by recent experimental and theoretical studies of fewparticle
vortex clusters in Bose-Einstein condensates, we consider the ordinary
differential equations of motion and systematically examine settings for up to
N = 6 vortices. We analyze the existence of corresponding stationary state
configurations and also consider their spectral stability properties. We
compare our particle model results with the predictions of the full partial
differential equation system. Whenever possible, we propose generalizations of
these results in the context of clusters of N vortices. Some of these, we can
theoretically establish, especially so for the N-vortex polygons, while others
we state as conjectures, e.g. for the N-vortex line equilibrium.


title: Structural aspects of asymptotically safe black holes

abstract:
  We study the quantum modifications of classical, spherically symmetric
Schwarzschild (Anti-) de Sitter black holes within Quantum Einstein Gravity.
The quantum effects are incorporated through the running coupling constants
$G_k$ and $\Lambda_k$, computed within the exact renormalization group
approach, and a common scale-setting procedure. We find that, in contrast to
common intuition, it is actually the cosmological constant that determines the
short-distance structure of the RG-improved black hole: in the asymptotic UV
the structure of the quantum solutions is universal and given by the classical
Schwarzschild-de Sitter solution, entailing a self-similarity between the
classical and quantum regime. As a consequence asymptotically safe black holes
evaporate completely and no Planck-size remnants are formed. Moreover, the
thermodynamic entropy of the critical Nariai-black hole is shown to agree with
the microstate count based on the effective average action, suggesting that the
entropy originates from quantum fluctuations around the mean-field geometry.


title: Beyond Locality-Sensitive Hashing

abstract:
  We present a new data structure for the c-approximate near neighbor problem
(ANN) in the Euclidean space. For n points in R^d, our algorithm achieves
O(n^{\rho} + d log n) query time and O(n^{1 + \rho} + d log n) space, where
\rho <= 7/(8c^2) + O(1 / c^3) + o(1). This is the first improvement over the
result by Andoni and Indyk (FOCS 2006) and the first data structure that
bypasses a locality-sensitive hashing lower bound proved by O'Donnell, Wu and
Zhou (ICS 2011). By a standard reduction we obtain a data structure for the
Hamming space and \ell_1 norm with \rho <= 7/(8c) + O(1/c^{3/2}) + o(1), which
is the first improvement over the result of Indyk and Motwani (STOC 1998).


title:
A First Look at Galaxy Flyby Interactions: Characterizing the Frequency
  of Flybys in a Cosmological Context

abstract:
  Hierarchical structure formation theory is based on the notion that mergers
drive galaxy evolution, so a considerable framework of semi-analytic models and
N-body simulations has been constructed to calculate how mergers transform a
growing galaxy. However, galaxy mergers are only one type of major dynamical
interaction between halos -- another class of encounter, a close flyby, has
been largely ignored. We analyze a 50 Mpc/h, $1024^3$ collisionless
cosmological simulation and find that the number of close flyby interactions is
comparable to, or even surpasses, the number of mergers for halo masses $\ga
10^{11}\,{h^{-1} M_\odot}$ at $z \la 2$. Halo flybys occur so frequently to
high mass halos that they are continually perturbed, unable to reach a
dynamical equilibrium. We also find tentative evidence that at high redshift,
$z \ga 14$, flybys are as frequent as mergers. Our results suggest that close
halo flybys can play an important role in the evolution of the earliest dark
matter halos and their galaxies, and can still influence galaxy evolution at
the present epoch.


title: Supernova spectra below strong circum-stellar interaction

abstract:
  We construct spectra of supernovae interacting strongly with a circumstellar
medium (CSM) by adding SN templates, a black-body continuum and an
emission-line spectrum. In a Monte Carlo simulation we generate more than 800
spectra, distribute them to 10 different classifiers and study how the
different simulation parameters affect the appearance of the spectra. SNe IIn
showing some structure over the continuum were characterized as SNe IInS. We
demonstrate that the flux ratio of the underlying SN to the continuum fv is the
most important parameter determining the spectral classification. Thermonuclear
SNe get progressively classified as Ia-CSM, IInS and IIn as fv decreases. The
transition between Ia-CSM and IInS occurs at fv~0.2-0.3. It shown that SNe
Ia-CSM are found at the magnitude range -19.5> M >-21.6, in good agreement with
observations, and that the faintest SN IIn that can hide a SN Ia has M = -20.1.
The sample of SNe Ia-CSM shows an association with 91T-like SNe Ia. Our
experiment does not support that this association is due to a luminosity bias
(91T-like being brighter than normal Ia). We therefore conclude that this
association has real physical origins and we propose that 91T-like explosions
result from single degenerate progenitors. Despite the similarities between SNe
Ibc and SNe Ia, the number of misclassifications between these types was small
and mostly at low S/N. Combined with the luminosity function needed to
reproduce the observed SN Ia-CSM luminosities, it is unlikely that SNe Ibc
constitute an important contaminant within this sample. We show how Type II
spectra transition to IIn and how the Ha profiles vary with fv. SNe IIn fainter
than M = -17.2 are unable to mask SNe IIP brighter than M = -15. A simulation
including radiative transfer shows that our simplified model is a good first
order approximation. The spectra obtained are in good agreement with real data.


title:
Multiphoton-double-ionization probability linearly depends on laser
  intensity: Experimental studies of barium

abstract:
  Despite inherently complex multiphoton dynamics, our observations show that
Ba double ionization with an infrared laser (8800-8920 cm^{-1}) resembles a
single-photon process; namely, its probability is proportional to the laser
intensity. In this regime, single-electron ionization is due to a four-photon
resonant transition through the highly perturbed state 6p^2 1D_2, whereas
double ionization is realized by the two-electron mechanism. Furthermore, we
argue that these conclusions are valid for other alkaline-earth-metal atoms and
other parameters of laser radiation.


title: Transport-induced correlations in weakly interacting systems

abstract:
  We study spatial correlations in the transport of energy between two baths at
different temperatures. To do this, we introduce a minimal model in which
energy flows from one bath to another through two subsystems. We show that the
transport-induced energy correlations between the two subsystems are of the
same order as the energy fluctuations within each subsystem. The correlations
can be either positive or negative and we give bounds on their values which are
associated with a dynamic energy scale. The different signs originate as a
competition between fluctuations generated near the baths, and fluctuations of
the current between the two subsystems. This interpretation sheds light on
known results for spatially-dependent heat and particle conduction models.


title:
Absorbed Dose in Ion Beams: Comparison of Ionisation and Fluence-based
  Measurements

abstract:
  A direct comparison measurement of fluorescent nuclear track detectors
(FNTDs) and a thimble ionisation chamber is presented. Irradiations were
performed using monoenergetic protons (142.66 MeV, 3*10^6 1/cm2) and carbon
ions (270.55 MeV/u, 3*10^6 1/cm2). It was found that absorbed dose to water
values as determined by fluence measurements using FNTDs are, in case of
protons, in good agreement (2.4 %) with ionization chamber measurements, if
slower protons and Helium secondaries were accounted for by an effective
stopping power. For carbon, however, a significant discrepancy of 4.5 % was
seen, which could not be explained by fragmentation, uncertainties or
experimental design. The results rather suggest a W-value of 32.10 eV +/- 2.6
%. Additionally, the abundance of secondary protons expected from Monte-Carlo
transport simulation was not observed.


title: Direct Uncertainty Estimation in Reinforcement Learning

abstract:
  Optimal probabilistic approach in reinforcement learning is computationally
infeasible. Its simplification consisting in neglecting difference between true
environment and its model estimated using limited number of observations causes
exploration vs exploitation problem. Uncertainty can be expressed in terms of a
probability distribution over the space of environment models, and this
uncertainty can be propagated to the action-value function via Bellman
iterations, which are computationally insufficiently efficient though. We
consider possibility of directly measuring uncertainty of the action-value
function, and analyze sufficiency of this facilitated approach.


title: The quantum unique ergodicity conjecture for thin sets

abstract:
  We consider some analogs of the quantum unique ergodicity conjecture for
geodesics, horocycles, or ``shrinking'' families of sets. In particular, we
prove the analog of the QUE conjecture for Eisenstein series restricted to the
infinite geodesic connecting 0 and infinity inside the modular surface.


title:
Enhanced light-matter interaction in graphene-covered gold nanovoid
  arrays

abstract:
  The combination of graphene with noble-metal nanostructures is currently
being explored for strong light-graphene interaction enhanced by plasmons. We
introduce a novel hybrid graphene-metal system for studying light-matter
interactions with gold-void nanostructures exhibiting resonances in the visible
range. Strong coupling of graphene layers to the plasmon modes of the nanovoid
arrays results in significant frequency shifts of the underlying plasmon
resonances, enabling more than 30% absolute light absorption in a single layer
of graphene and up to 700-fold enhancement of the Raman response of the
graphene. These new perspectives enable us to verify the presence of graphene
on gold-void arrays and the enhancement even allows us to accurately quantify
the number of layers. Experimental observations are further supported by
numerical simulations and perturbation-theory analysis. The graphene gold-void
platform is beneficial for sensing of molecules and placing R6G dye molecules
on top of the graphene, we observe a strong enhancement of the R6G Raman
fingerprints. These results pave the way toward advanced substrates for
surface-enhanced Raman scattering (SERS) with potential for unambiguous
single-molecule detection on the atomically well-defined layer of graphene.


title:
Diversity Polynomials for the Analysis of Temporal Correlations in
  Wireless Networks

abstract:
  The interference in wireless networks is temporally correlated, since the
node or user locations are correlated over time and the interfering
transmitters are a subset of these nodes. For a wireless network where
(potential) interferers form a Poisson point process and use ALOHA for channel
access, we calculate the joint success and outage probabilities of n
transmissions over a reference link. The results are based on the diversity
polynomial, which captures the temporal interference correlation. The joint
outage probability is used to determine the diversity gain (as the SIR goes to
infinity), and it turns out that there is no diversity gain in simple
retransmission schemes, even with independent Rayleigh fading over all links.
We also determine the complete joint SIR distribution for two transmissions and
the distribution of the local delay, which is the time until a repeated
transmission over the reference link succeeds.


title:
Extending Universal Intelligence Models with Formal Notion of
  Representation

abstract:
  Solomonoff induction is known to be universal, but incomputable. Its
approximations, namely, the Minimum Description (or Message) Length (MDL)
principles, are adopted in practice in the efficient, but non-universal form.
Recent attempts to bridge this gap leaded to development of the
Representational MDL principle that originates from formal decomposition of the
task of induction. In this paper, possible extension of the RMDL principle in
the context of universal intelligence agents is considered, for which
introduction of representations is shown to be an unavoidable meta-heuristic
and a step toward efficient general intelligence. Hierarchical representations
and model optimization with the use of information-theoretic interpretation of
the adaptive resonance are also discussed.


title: Conjugacy classes of finite groups and graph regularity

abstract:
  Given a finite group $G$, denote by $\Gamma(G)$ the simple undirected graph
whose vertices are the distinct sizes of noncentral conjugacy classes of $G$,
and set two vertices of $\Gamma(G)$ to be adjacent if and only if they are not
coprime numbers. In this note we prove that, if $\Gamma(G)$ is a $k$-regular
graph with $k\geq 1$, then $\Gamma(G)$ is a complete graph with $k+1$ vertices.


title: On the fundamental tone of immersions and submersions

abstract:
  In this paper we obtain lower bound estimates of the spectrum of
Laplace-Beltrami operator on complete submanifolds with bounded mean curvature,
whose ambient space admits a Riemannian submersion over a Riemannian manifold
with negative sectional curvature. Our main theorem generalizes many previous
known estimates and applies for both immersions and submersions.


title:
Theory of Fluctuating Charge Ordering in the Pseudogap Phase of the
  Cuprates Via A Preformed Pair Approach

abstract:
  We study the static and dynamic behavior of charge ordering within a d-wave
pair pseudogap (pg) scenario. This is addressed using a density-density
correlation function derived from the standard pg self energy, $\Sigma$ and
compatible with the longitudinal and transverse sum rules. The broadening
factor $\gamma$ in $\Sigma$ reflects the breaking of pairs into constituent
fermions. We apply this form for $\Sigma$ (derived elsewhere for high fields)
to demonstrate the existence of quantum oscillations in a non-Fermi liquid pg
state. Our conclusion is that the pseudogap-induced pairbreaking, via $\gamma$,
allows the underlying fermiology to be revealed; in YBCO, finite $\omega$ and
$\gamma$ enable antinodal fluctuations, despite the competition with a d-wave
gap in the static and superconducting limits.


title: A Curie-Weiss Model of Self-Organized Criticality : The Gaussian Case

abstract:
  We try to design a simple model exhibiting self-organized criticality, which
is amenable to a rigorous mathematical analysis. To this end, we modify the
generalized Ising Curie-Weiss model by implementing an automatic control of the
inverse temperature. With the help of exact computations, we show that, in the
case of a centered Gaussian measure with positive variance $\sigma^{2}$, the
sum $S_n$ of the random variables has fluctuations of order $n^{3/4}$ and that
$S_n/n^{3/4}$ converges to the distribution $C \exp(-x^{4}/(4\sigma^4))\,dx$
where $C$ is a suitable positive constant.


title:
Computing General Relativistic effects from Newtonian N-body
  simulations: Frame dragging in the post-Friedmann approach

abstract:
  We present the first calculation of an intrinsically relativistic quantity in
fully non-linear cosmolog- ical large-scale structure studies. Traditionally,
non-linear structure formation in standard {\Lambda}CDM cosmology is studied
using N-body simulations, based on Newtonian gravitational dynamics on an
expanding background. When one derives the Newtonian regime in a way that is a
consistent ap- proximation to the Einstein equations, a gravito-magnetic vector
potential - giving rise to frame dragging - is present in the metric in
addition to the usual Newtonian scalar potential. At leading order, this vector
potential does not affect the matter dynamics, thus it can be computed from
Newtonian N-body simulations. We explain how we compute the vector potential
from simulations in {\Lambda}CDM and examine its magnitude relative to the
scalar potential. We also discuss some possible observable effects.


title:
A measurement of galaxy halo mass from the surrounding HI Ly{\alpha}
  absorption

abstract:
  We measure the dark matter halo masses of z~2.36 UV color-selected
star-forming galaxies by matching the observed median HI Ly{\alpha} absorption
around them, as observed in the spectra of background QSOs, to the absorption
around haloes above a given mass in cosmological simulations. Focusing on
transverse separations 0-2 pMpc and line of sight separations 154-616 km/s, we
find a minimum halo mass of log10(Mmin/Msun)=11.6(+0.2)(-0.2), which is in good
agreement with published halo mass estimates from clustering analyses. We
verified that the measured halo mass is insensitive to a change in the
cosmological parameters (WMAP1 vs. WMAP3) and to the inclusion of strong AGN
feedback. One unique strength of this method is that it can be used in narrow
field galaxy-QSO surveys, i.e. ~30 x 30 arcseconds. In addition, we find that
the observed anisotropy in the 2-D HI Ly{\alpha} absorption distribution on
scales of 1.5-2 pMpc is consistent with being a consequence of large-scale gas
infall into the potential wells occupied by galaxies.


title: Far from standard Higgs couplings

abstract:
  In this short note we consider a permitted region in the space of couplings
of the 126 GeV boson that extends far away from the standard model Higgs
couplings. This region is of interest for more natural models of electroweak
symmetry breaking. Stronger evidence of vector boson fusion and/or associated
production is needed to eliminate this possibility.


title: Proof of Heisenberg's error-disturbance relation

abstract:
  While the slogan "no measurement without disturbance" has established itself
under the name Heisenberg effect in the consciousness of the scientifically
interested public, a precise statement of this fundamental feature of the
quantum world has remained elusive, and serious attempts at rigorous
formulations of it as a consequence of quantum theory have led to seemingly
conflicting preliminary results. Here we show that despite recent claims to the
contrary [Rozema et al, Phys. Rev. Lett. 109, 100404 (2012)], Heisenberg-type
inequalities can be proven that describe a trade-off between the precision of a
position measurement and the necessary resulting disturbance of momentum (and
vice versa). More generally, these inequalities are instances of an uncertainty
relation for the imprecisions of any joint measurement of position and
momentum. Measures of error and disturbance are here defined as figures of
merit characteristic of measuring devices. As such they are state independent,
each giving worst-case estimates across all states, in contrast to previous
work that is concerned with the relationship between error and disturbance in
an individual state.


title: Ferromagnetism and infrared electrodynamics of Ga$_{1-x}$Mn$_{x}$As}

abstract:
  We report on the magnetic and the electronic properties of the prototype
dilute magnetic semiconductor Ga$_{1-x}$Mn$_x$As using infrared (IR)
spectroscopy. Trends in the ferromagnetic transition temperature $T_C$ with
respect to the IR spectral weight are examined using a sum-rule analysis of IR
conductivity spectra. We find non-monotonic behavior of trends in $T_C$ with
the spectral weight to effective Mn ratio, which suggest a strong
double-exchange component to the FM mechanism, and highlights the important
role of impurity states and localization at the Fermi level. Spectroscopic
features of the IR conductivity are tracked as they evolve with temperature,
doping, annealing, As-antisite compensation, and are found only to be
consistent with an Mn-induced IB scenario. Furthermore, our detailed
exploration of these spectral features demonstrates that seemingly conflicting
trends reported in the literature regarding a broad mid-IR resonance with
respect to carrier density in Ga$_{1-x}$Mn$_x$As are in fact not contradictory.
Our study thus provides a consistent experimental picture of the magnetic and
electronic properties of Ga$_{1-x}$Mn$_x$As.


title: Dark matter and collider signatures of the MSSM

abstract:
  We explore the MSSM with 9 free parameters (p9MSSM) that have been selected
as a minimum set that allows an investigation of neutralino dark matter and
collider signatures while maintaining consistency with several constraints.
These include measurement of the dark matter relic density from PLANCK, main
properties of the discovered Higgs boson, LHC direct SUSY searches, recent
evidence for a Standard Model-like BR(Bs -> \mu+ \mu-), and the measurement of
\delta(g-2), plus a number of other electroweak and flavor physics constraints.
We perform a simulation of two LHC direct SUSY searches at sqrt(s)=8 TeV: the
CMS inclusive \alpha_T search for squarks and gluinos and the CMS electroweak
production search with 3l+E_T^miss in the final state. We use the latter to
identify the regions of the parameter space, consistent at 2\sigma\ with
\delta(g-2), that are not excluded by the direct limits from the electroweak
production. We find that they correspond to a neutralino mass in the window 200
GeV<m_\chi<500 GeV. We also implement the likelihood for the XENON100 exclusion
bound, in which we consider for the first time the impact of a recent
determination of the \Sigma_{\pi N} term from CHAOS data, \Sigma_{\pi
N}=43\pm12 MeV. We show that in light of this measurement, the present
statistical impact of the XENON100 bound is greatly reduced, although future
sensitivities of the LUX and XENON1T experiments will have decisive impact on
the mixed bino/higgsino composition of the neutralino. We point out some
tension between the constraints from \delta(g-2) and XENON100. Finally, we
present prospects for various indirect searches of dark matter, namely
\gamma-ray fluxes from dSphs and the Galactic Center at Fermi-LAT, and the
positron flux at AMS02. We also show the 5-year sensitivity on the
spin-dependent neutralino-proton cross section due to neutrino fluxes from the
Sun at IceCube.


title:
Equilibrium and equivariant triangulations of some small covers with
  minimum number of vertices

abstract:
  Small covers were introduced by Davis and Januszkiewicz in 1991. We introduce
the notion of equilibrium triangulations for small covers. We study equilibrium
and vertex minimal $\mathbb{Z}_2^2$-equivariant triangulations of
$2$-dimensional small covers. We discuss vertex minimal equilibrium
triangulations of $\mathbb{RP}^3 \# \mathbb{RP}^3$, $S^1 \times \mathbb{RP}^2$
and a nontrivial $S^1$ bundle over $\mathbb{RP}^2$. We construct some nice
equilibrium triangulations of the real projective space $\mathbb{RP}^n$ with
$2^n +n+1$ vertices. The main tool is the theory of small covers.


title:
Low-bandwidth and non-compute intensive remote identification of
  microbes from raw sequencing reads

abstract:
  Cheap high-throughput DNA sequencing may soon become routine not only for
human genomes but also for practically anything requiring the identification of
living organisms from their DNA: tracking of infectious agents, control of food
products, bioreactors, or environmental samples.
  We propose a novel general approach to the analysis of sequencing data in
which the reference genome does not have to be specified. Using a distributed
architecture we are able to query a remote server for hints about what the
reference might be, transferring a relatively small amount of data, and the
hints can be used for more computationally-demanding work.
  Our system consists of a server with known reference DNA indexed, and a
client with raw sequencing reads. The client sends a sample of unidentified
reads, and in return receives a list of matching references known to the
server. Sequences for the references can be retrieved and used for exhaustive
computation on the reads, such as alignment.
  To demonstrate this approach we have implemented a web server, indexing tens
of thousands of publicly available genomes and genomic regions from various
organisms and returning lists of matching hits from query sequencing reads. We
have also implemented two clients, one of them running in a web browser, in
order to demonstrate that gigabytes of raw sequencing reads of unknown origin
could be identified without the need to transfer a very large volume of data,
and on modestly powered computing devices.
  A web access is available at http://tapir.cbs.dtu.dk. The source code for a
python command-line client, a server, and supplementary data is available at
http://bit.ly/1aURxkc.


title:
The X-ray Spectral Evolution of Galactic Black Hole X-ray Binaries
  Toward Quiescence

abstract:
  Most transient black hole X-ray binaries (BHXBs) spend the bulk of their time
in a quiescent state, where they accrete matter from their companion star at
highly sub-Eddington luminosities (we define quiescence here as a normalized
Eddington ratio l_x = L_{0.5-10 keV}}/L_{Edd} < 1e-5). Here, we present Chandra
X-ray imaging spectroscopy for three BHXB systems (H 1743-322, MAXI J1659-152,
and XTE J1752-223) as they fade into quiescence following an outburst. Multiple
X-ray observations were taken within one month of each other, allowing us to
track each individual system's X-ray spectral evolution during its decay. We
compare these three systems to other BHXB systems. We confirm that quiescent
BHXBs have softer X-ray spectra than low-hard state BHXBs, and that quiescent
BHXB spectral properties show no dependence on the binary system's orbital
parameters. However, the observed anti-correlation between X-ray photon index
and l_x in the low-hard state does not continue once a BHXB enters quiescence.
Instead, the photon index plateaus to an average value of 2.08+/-0.07 by the
time l_x reaches approximately 1e-5. l_x~1e-5 is thus an
observationally-motivated upper limit for the beginning of the quiescent
spectral state. Our results are discussed in the context of different accretion
flow models, and across the black hole mass scale.


title:
Testing local position and fundamental constant invariance due to
  periodic gravitation and boost using long-term comparison of the SYRTE atomic
  fountains and H-masers

abstract:
  The frequencies of three separate Cs fountain clocks and one Rb fountain
clock have been compared to various hydrogen masers to search for periodic
changes correlated with the changing solar gravitational potential at the Earth
and boost with respect to the Cosmic Microwave Background (CMB) rest frame. The
data sets span over more than eight years. The main sources of long-term noise
in such experiments are the offsets and linear drifts associated with the
various H-masers. The drift can vary from nearly immeasurable to as high as
1.3*10^-15 per day. To circumvent these effects we apply a numerical derivative
to the data, which significantly reduces the standard error when searching for
periodic signals. We determine a standard error for the putative Local Position
Invariance (LPI) coefficient with respect to gravity for a Cs-Fountain H-maser
comparison of 4.8*10^-6 and 10^-5 for a Rb-Fountain H-maser comparison. From
the same data the putative boost LPI coefficients were measured to a precision
of up to parts in 10^11 with respect to the CMB rest frame. By combining these
boost invariance experiments to a Cryogenic Sapphire Oscillator versus H-maser
comparison, independent limits on all nine coefficients of the boost violation
vector with respect to fundamental constant invariance (fine structure
constant, electron mass and quark mass respectively), were determined to a
precision of parts up to 10^10.


title: Algorithms for detecting dependencies and rigid subsystems for CAD

abstract:
  Geometric constraint systems underly popular Computer Aided Design soft-
ware. Automated approaches for detecting dependencies in a design are critical
for developing robust solvers and providing informative user feedback, and we
provide algorithms for two types of dependencies. First, we give a pebble game
algorithm for detecting generic dependencies. Then, we focus on identifying the
"special positions" of a design in which generically independent constraints
become dependent. We present combinatorial algorithms for identifying subgraphs
associated to factors of a particular polynomial, whose vanishing indicates a
special position and resulting dependency. Further factoring in the Grassmann-
Cayley algebra may allow a geometric interpretation giving conditions (e.g.,
"these two lines being parallel cause a dependency") determining the special
position.


title:
Modelling elastic structures with strong nonlinearities with application
  to stick-slip friction

abstract:
  An exact transformation method is introduced that reduces the governing
equations of a continuum structure coupled to strong nonlinearities to a low
dimensional equation with memory. The method is general and well suited to
problems with point discontinuities such as friction and impact at point
contact. It is assumed that the structure is composed of two parts: a continuum
but linear structure and finitely many discrete but strong nonlinearites acting
at various contact points of the elastic structure. The localised
nonlinearities include discontinuities, e.g., the Coulomb friction law. Despite
the discontinuities in the model, we demonstrate that contact forces are
Lipschitz continuous in time at the onset of sticking for certain classes of
structures. The general formalism is illustrated for a continuum elastic body
coupled to a Coulomb-like friction model.


title: 100 million years after the Big Bang

abstract:
  Dark Energy Camera on the Blanco 4 meter telescope not only has the focal
plane size the 4 meters were built for, but also has excellent near infrared
response. A DECam Deep Fields program is outlined, which can reach M* galaxies
at redshift 6 at a wavelength of one micron. What reionized the Universe, when
did globular clusters form, were there very massive stars and how did they end,
and how did supermassive black holes emerge a few hundred million years after
the Big Bang ? These are some of the questions wide field high z surveys in the
infrared will open to observational study.


title: Ultrastrong and Ultrastable Metallic Glass

abstract:
  The lack of thermal stability, originating from their metastable nature, has
been one of the paramount obstacles that hinder the wide range of applications
of metallic glasses. We report that the stability of a metallic glass can be
dramatically improved by slow deposition at high temperatures. The glass
transition and crystallization temperatures of the ultrastable metallic glass
can be increased by 51 K and 203 K, respectively, from its ordinary glass
state. The ultrastable metallic glass also shows ultrahigh strength and
hardness, over 30 % higher than its ordinary counterpart. Atomic structure
characterization reveals that the exceptional properties of the ultrastable
glass are associated with abundance of medium range order. The finding of the
ultrastable metallic glass sheds light on atomic mechanisms of metallic glass
formation and has important impact on the technological applications of
metallic glasses.


title: Instability of quantum equilibrium in Bohm's dynamics

abstract:
  We consider Bohm's second-order dynamics for arbitrary initial conditions in
phase space. In principle Bohm's dynamics allows for 'extended' nonequilibrium,
with initial momenta not equal to the gradient of phase of the wave function
(as well as initial positions whose distribution departs from the Born rule).
We show that extended nonequilibrium does not relax in general and is in fact
unstable. This is in sharp contrast with de Broglie's first-order dynamics, for
which non-standard momenta are not allowed and which shows an efficient
relaxation to the Born rule for positions. On this basis we argue that, while
de Broglie's dynamics is a tenable physical theory, Bohm's dynamics is not. In
a world governed by Bohm's dynamics there would be no reason to expect to see
an effective quantum theory today (even approximately), in contradiction with
observation.


title:
The compact, time-variable radio source projected inside W3(OH):
  Evidence for a Photoevaporated Disk?

abstract:
  We present new Karl G. Jansky Very Large Array observations of the compact (~
0.05"), time-variable radio source projected near the center of the
ultracompact HII region W3(OH). The analysis of our new data as well as of VLA
archival observations confirms the variability of the source on timescales of
years and for a given epoch indicates a spectral index of \alpha = 1.3 +- 0.3
(S_\nu \propto \nu^\alpha). This spectral index and the brightness temperature
of the source (~6,500 K) suggest that we are most probably detecting partially
optically thick free-free radiation. The radio source is probably associated
with the ionizing star of W3(OH), but an interpretation in terms of an ionized
stellar wind fails because the detected flux densities are orders of magnitude
larger than expected. We discuss several scenarios and tentatively propose that
the radio emission could arise in a static ionized atmosphere around a fossil
photoevaporated disk.


title: Emitters of $N$-photon bundles

abstract:
  We propose a scheme based on the coherent excitation of a two-level system in
a cavity to generate an ultrabright CW and focused source of quantum light that
comes in groups (bundles) of $N$ photons, for an integer $N$ tunable with the
frequency of the exciting laser. We define a new quantity, the \emph{purity} of
$N$-photon emission, to describe the percentage of photons emitted in bundles,
thus bypassing the limitations of Glauber correlation functions. We focus on
the case $1\le N\le3$ and show that close to 100% of two-photon emission and
90% of three-photon emission is within reach of state of the art cavity QED
samples. The statistics of the bundles emission shows that various
regimes---from $N$-photon lasing to $N$-photon guns---can be realized. This is
evidenced through generalized correlation functions that extend the standard
definitions to the multi-photon level.


title:
Mechanism for the suppression of quantum noise at large scales on
  expanding space

abstract:
  We present an exactly-solvable model for the suppression of quantum noise at
large scales on expanding space. The suppression arises naturally in the de
Broglie-Bohm pilot-wave formulation of quantum theory, according to which the
Born probability rule has a dynamical origin. For a scalar field on a
radiation-dominated background we construct the exact solution for the
time-evolving wave functional and study properties of the associated field
trajectories. It is shown that the time evolution of a field mode on expanding
space is mathematically equivalent to that of a standard harmonic oscillator
with a 'retarded time' that depends on the wavelength of the mode. In the far
super-Hubble regime the equivalent oscillator evolves over only one Hubble
time, yielding a simple mechanism whereby relaxation to the Born rule can be
suppressed on very large scales. We present numerical simulations illustrating
how the expansion of space can cause a retardation of relaxation in the
super-Hubble regime. Given these results it is natural to expect a suppression
of quantum noise at super-Hubble wavelengths. Such suppression could have taken
place in a pre-inflationary era, resulting in a large-scale power deficit in
the cosmic microwave background.


title: Dense domains, symmetric operators and spectral triples

abstract:
  This article is about erroneous attempts to weaken the standard definition of
unbounded Kasparov module (or spectral triple). We present counterexamples to
claims in the literature that Fredholm modules can be obtained from these
weaker variations of spectral triple. Our counterexamples are constructed using
self-adjoint extensions of symmetric operators.


title: A Rigidity Theorem for Hypersurfaces in Higher Dimensional Space Forms

abstract:
  The classical Cohn-Vossen theorem states that two isometric compact convex
surfaces in $\mathbb{R}^{3}$ are congruent. In this short note, we generalize
the classical Cohn-Vossen Theorem to higher dimensional surfaces in space form
$N^{n+1}(K)$ for $n\ge 2$.


title:
Topological full groups of $C^*$-algebras arising from
  $\beta$-expansions

abstract:
  We will introduce a family $\Gamma_\beta, 1 < \beta \in {\mathbb{R}}$ of
infinite non-amenable discrete groups as an interpolation of the
Higman-Thompson groups $V_n, 1 < n \in {\mathbb{N}}$ by using the topological
full groups of the groupoids defined by $\beta$-expansions of real numbers.
They are regarded as full groups of certain interpolated Cuntz algebras. The
groups $\Gamma_\beta, 1 < \beta \in {\mathbb{R}}$ are realized as groups of
piecewise linear functions on $[0,1]$ if the $\beta$-expansion of $1$ is finite
or ultimately periodic. We also classify the groups $\Gamma_\beta, 1 < \beta
\in {\mathbb{R}}$ by the number theoretical property of $\beta$.


title:
Galaxy And Mass Assembly (GAMA): A deeper view of the mass, metallicity,
  and SFR relationships

abstract:
  A full appreciation of the role played by gas metallicity (Z), star-formation
rate (SFR), and stellar mass is fundamental to understanding how galaxies form
and evolve. The connections between these three parameters at different
redshifts significantly affect galaxy evolution, and thus provide important
constraints for galaxy evolution models. Using data from the Sloan Digital Sky
Survey-Data Release 7 (SDSS-DR7) and the Galaxy and Mass Assembly (GAMA)
surveys we study the relationships and dependencies between SFR, Z, and stellar
mass, as well as the Fundamental Plane for star-forming galaxies. We combine
both surveys using volume-limited samples up to a redshift of z ~ 0.36. The
GAMA and SDSS surveys complement each other when analyzing the relationships
between SFR, Mass and Z. We present evidence for SFR and metallicity evolution
to z ~ 0.2. We study the dependencies between SFR, Mass, Z, and specific
star-formation rate (SSFR) on the M-Z, M-SFR, M-SSFR, Z-SFR, and Z-SSFR
relations, finding strong correlations between all. Based on those
dependencies, we propose a simple model that allows us to explain the different
behaviour observed between low and high mass galaxies. Finally, our analysis
allows us to confirm the existence of a Fundamental Plane, for which Mass=f(Z,
SFR) in star-forming galaxies.


title:
A Radiation-Hydrodynamics Code Comparison for Laser-Produced Plasmas:
  FLASH versus HYDRA and the Results of Validation Experiments

abstract:
  The potential for laser-produced plasmas to yield fundamental insights into
high energy density physics (HEDP) and deliver other useful applications can
sometimes be frustrated by uncertainties in modeling the properties and
expansion of these plasmas using radiation-hydrodynamics codes. In an effort to
overcome this and to corroborate the accuracy of the HEDP capabilities recently
added to the publicly available FLASH radiation-hydrodynamics code, we present
detailed comparisons of FLASH results to new and previously published results
from the HYDRA code used extensively at Lawrence Livermore National Laboratory.
We focus on two very different problems of interest: (1) an Aluminum slab
irradiated by 15.3 and 76.7 mJ of "pre-pulse" laser energy and (2) a mm-long
triangular groove cut in an Aluminum target irradiated by a rectangular laser
beam. Because this latter problem bears a resemblance to astrophysical jets,
Grava et al., Phys. Rev. E, 78, (2008) performed this experiment and compared
detailed x-ray interferometric measurements of electron number densities to
HYDRA simulations. Thus, the former problem provides an opportunity for
code-to-code comparison, while the latter provides an opportunity for both
code-to-code comparison and validation. Despite radically different schemes for
determining the computational mesh, and different equation of state and opacity
models, the HYDRA and FLASH codes yield results that are in excellent agreement
for both problems and with the experimental data for the latter. Having
validated the FLASH code in this way, we use the code to further investigate
the formation of the jet seen in the Grava et al. (2008) experiment and discuss
its relation to the Wan et al. (1997) experiment at the NOVA laser.


title: Some properties of surface diffeomorphisms

abstract:
  We obtain some properties of $C^1$ generic surface diffeomorphisms as
finiteness of {\em non-trivial} attractors, approximation by diffeomorphisms
with only a finite number of {\em hyperbolic} homoclinic classes, equivalence
between essential hyperbolicity and the hyperbolicity of all {\em dissipative}
homoclinic classes (and the finiteness of spiral sinks). In particular, we
obtain the equivalence between finiteness of sinks and finiteness of spiral
sinks, abscence of domination in the set of accumulation points of the sinks,
and the equivalence between Axiom A and the hyperbolicity of all homoclinic
classes. These results improve \cite{A}, \cite{a}, \cite{m} and settle a
conjecture by Abdenur, Bonatti, Crovisier and D\'{i}az \cite{abcd}.


title:
Strong converse for the classical capacity of entanglement-breaking and
  Hadamard channels via a sandwiched Renyi relative entropy

abstract:
  A strong converse theorem for the classical capacity of a quantum channel
states that the probability of correctly decoding a classical message converges
exponentially fast to zero in the limit of many channel uses if the rate of
communication exceeds the classical capacity of the channel. Along with a
corresponding achievability statement for rates below the capacity, such a
strong converse theorem enhances our understanding of the capacity as a very
sharp dividing line between achievable and unachievable rates of communication.
Here, we show that such a strong converse theorem holds for the classical
capacity of all entanglement-breaking channels and all Hadamard channels (the
complementary channels of the former). These results follow by bounding the
success probability in terms of a "sandwiched" Renyi relative entropy, by
showing that this quantity is subadditive for all entanglement-breaking and
Hadamard channels, and by relating this quantity to the Holevo capacity. Prior
results regarding strong converse theorems for particular covariant channels
emerge as a special case of our results.