title: Triply Existentially Complete Triangle-Free Graphs

abstract:
  A triangle-free graph G is called k-existentially complete if for every
induced k-vertex subgraph H of G, every extension of H to a (k+1)-vertex
triangle-free graph can be realized by adding another vertex of G to H. Cherlin
asked whether k-existentially complete triangle-free graphs exist for every k.
Here we present known and new constructions of 3-existentially complete
triangle-free graphs.


title:
Equivalence of Particle-Particle Random Phase Approximation Correlation
  Energy and Ladder-Coupled-Cluster-Double

abstract:
  We present an analytical proof and numerical demonstrations of the
equivalence of the correlation energy from particle-particle random phase
approximation (pp-RPA) and ladder-couple-cluster-doubles (ladder-CCD). These
two theories reduce to the identical algebraic matrix equation and correlation
energy expressions, under the assumption that the pp-RPA equation is stable.
The numerical examples illustrate that the correlation energy missed by pp-RPA
in comparison with couple-cluster single and double is largely canceled out
when considering reaction energies. This theoretical connection will be
beneficial to future pp-RPA studies based on the well established couple
cluster theory.


title: On the Geometrical Gyro-Kinetic Theory

abstract:
  Considering a Hamiltonian Dynamical System describing the motion of charged
particle in a Tokamak or a Stellarator, we build a change of coordinates to
reduce its dimension. This change of coordinates is in fact an intricate
succession of mappings that are built using Hyperbolic Partial Differential
Equations, Differential Geometry, Hamiltonian Dynamical System Theory and
Symplectic Geometry, Lie Transforms and a new tool which is here introduced :
Partial Lie Sums.

categories: physics.plasm-ph math-ph math.AP math.DG math.MP


title: Dynamical correlations in a glass-former with randomly pinned particles

abstract:
  The effects of randomly pinning particles in a model glass-forming fluid are
studied, with a focus on the dynamically heterogeneous relaxation in the
presence of pinning. We show how four-point dynamical correlations can be
analysed in real space, allowing direct extraction of a length scale that
characterises dynamical heterogeneity. In the presence of pinning, the
relaxation time of the glassy system increases by up to two decades, but there
is almost no increase in either the four-point correlation length or the
strength of the four-point correlations. We discuss the implications of these
results for theories of the glass transition.


title:
Dynamics of the Tippe Top -- properties of numerical solutions versus
  the dynamical equations

abstract:
  We study the relationship between numerical solutions for inverting Tippe Top
and the structure of the dynamical equations. The numerical solutions confirm
oscillatory behaviour of the inclination angle $\theta(t)$ for the symmetry
axis of the Tippe Top. They also reveal further fine features of the dynamics
of inverting solutions defining the time of inversion. These features are
partially understood on the basis of the underlying dynamical equations.


title: Gamma-ray emission from the Westerlund 1 region

abstract:
  Westerlund 1 (Wd 1) is the most massive stellar cluster in the Galaxy and
associated with an extended region of TeV emission. Here we report the results
of a search for GeV gamma-ray emission in this region. The analysis is based on
~4.5 years of Fermi-LAT data and reveals significantly extended emission which
we model as a Gaussian, resulting in a best-fit sigma of sigma_S = (0.475 +/-
0.05) deg and an offset from Wd 1 of ~1 deg. A partial overlap of the GeV
emission with the TeV signal as reported by H.E.S.S. is found. We investigate
the spectral and morphological characteristics of the gamma-ray emission and
discuss its origin in the context of two distinct scenarios. Acceleration of
electrons in a Pulsar Wind Nebula provides a reasonably natural interpretation
of the GeV emission, but leaves the TeV emission unexplained. A scenario in
which protons are accelerated in or near Wd 1 in supernova explosion(s) and are
diffusing away and interacting with molecular material, seems consistent with
the observed GeV and TeV emission, but requires a very high energy input in
protons, ~10^51 erg, and rather slow diffusion. Observations of Wd 1 with a
future gamma-ray detector such as CTA provide a very promising route to fully
resolve the origin of the TeV and GeV emission in Wd 1 and provide a deeper
understanding of the high-energy (HE) astrophysics of massive stellar clusters.


title: Coupled Kardar-Parisi-Zhang Equations in One Dimension

abstract:
  Over the past years our understanding of the scaling properties of the
solutions to the one-dimensional KPZ equation has advanced considerably, both
theoretically and experimentally. In our contribution we export these insights
to the case of coupled KPZ equations in one dimension. We establish equivalence
with nonlinear fluctuating hydrodynamics for multi-component driven stochastic
lattice gases. To check the predictions of the theory, we perform Monte Carlo
simulations of the two-component AHR model. Its steady state is computed using
the matrix product ansatz. Thereby all coefficients appearing in the coupled
KPZ equations are deduced from the microscopic model. Time correlations in the
steady state are simulated and we confirm not only the scaling exponent, but
also the scaling function and the non-universal coefficients.

categories: cond-mat.stat-mech math-ph math.MP math.PR


title: Evolution equations beyond one loop from conformal symmetry

abstract:
  We study implications of exact conformal invariance of scalar quantum field
theories at the critical point in non-integer dimensions for the evolution
kernels of the light-ray operators in physical (integer) dimensions. We
demonstrate that all constraints due the conformal symmetry are encoded in the
form of the generators of the collinear sl(2) subgroup. Two of them, S_- and
S_0, can be fixed at all loops in terms of the evolution kernel, while the
generator of special conformal transformations, S_+, receives nontrivial
corrections which can be calculated order by order in perturbation theory.
Provided that the generator S_+ is known at the k-1 loop order, one can fix the
evolution kernel in physical dimension to the k-loop accuracy up to terms that
are invariant with respect to the tree-level generators. The invariant parts
can easily be restored from the anomalous dimensions. The method is illustrated
on two examples: The O(n)-symmetric phi^4 theory in d=4 to the three-loop
accuracy, and the su(n) matrix phi^3 theory in d=6 to the two-loop accuracy. We
expect that the same technique can be used in gauge theories e.g. in QCD.


title: Intersecting 1-factors and nowhere-zero 5-flows

abstract:
  Let $G$ be a bridgeless cubic graph, and $\mu_2(G)$ the minimum number $k$
such that two 1-factors of $G$ intersect in $k$ edges. A cyclically
$n$-edge-connected cubic graph $G$ has a nowhere-zero 5-flow if (1) $n \geq 6$
and $\mu_2(G) \leq 2$ or (2) if $n \geq 5 \mu_2(G)-3$


title:
SL2 homomorphic hash functions: Worst case to average case reduction and
  short collision search

abstract:
  We study homomorphic hash functions into SL(2,q), the 2x2 matrices with
determinant 1 over the field with $q$ elements. Modulo a well supported number
theoretic hypothesis, which holds in particular for concrete homomorphisms
proposed thus far, we provide a worst case to average case reduction for these
hash functions: upto a logarithmic factor, a random homomorphism is as secure
as _any_ concrete homomorphism. For a family of homomorphisms containing
several concrete proposals in the literature, we prove that collisions of
length O(log(q)) can be found in running time O(sqrt(q)). For general
homomorphisms we offer an algorithm that, heuristically and according to
experiments, in running time O(sqrt(q)) finds collisions of length O(log(q))
for q even, and length O(log^2(q)/loglog(q))$ for arbitrary q. While exponetial
time, our algorithms are faster in practice than all earlier generic
algorithms, and produce much shorter collisions.


title:
The Goldstone theorem protects naturalness, and the absence of
  Brout-Englert-Higgs fine-tuning, in spontaneously broken SO(2)

abstract:
  The Gell-Mann-Levy (GML), Schwinger and Standard Models were previously shown
to lack a Brout-Englert-Higgs (BEH) fine-tuning problem due to quadratic
divergences, with finite Euclidean cut-off \Lambda, because of the symmetries
obeyed by all O(\Lambda^2) contributions. We extend those results to finite
contributions from certain M_{Heavy}^2>> m_{BEH}^2 particles in SO(2) versions
of GML and Schwinger. We demonstrate explicit 1-loop physical naturalness for
two SO(2) singlet examples: a heavy real scalar S and a right-handed Type 1
see-saw Majorana neutrino. We prove that for low |q^2| the heavy degrees of
freedom contribute, at worst, marginal operators in spontaneously broken SO(2)
Schwinger.
  The key GML lesson from these examples is that the pseudo Nambu-Goldstone
boson (NGB) mass-squared must be properly renormalized. A true NGB value, m_3^2
= 0, is then protected by the Goldstone theorem. For the Schwinger model, two
crucial observations emerge: global Ward-Takahashi identities (WTI) force all
relevant operators into the pseudo-NGB mass-squared; and WTI enforce the
Goldstone theorem by forbidding all relevant operator contributions in the
spontaneously broken Goldstone mode, \pi_3 is a massless NGB there. Goldstone
mode, with weak-scale m_{BEH}^2 \& <H>^2, is not-fine-tuned even as a
low-energy effective theory with certain high-mass-scale extensions. Its
"Goldstone Exceptional Naturalness (GEN)," where all relevant operators vanish,
a powerful suppression of fine-tuning, is simply another (albeit un-familiar)
consequence of WTI, spontaneous symmetry breaking and the Goldstone theorem.
  If GEN can somehow be extended to the Standard Model (SM), there should be no
expectation that LHC will discover any Beyond the SM physics unrelated to
neutrino mixing, i.e. the only known experimentally necessary modification of
the Standard Model plus General Relativity paradigm.


title:
Trace representation and linear complexity of binary sequences derived
  from Fermat quotients

abstract:
  We describe the trace representations of two families of binary sequences
derived from Fermat quotients modulo an odd prime $p$ (one is the binary
threshold sequences, the other is the Legendre-Fermat quotient sequences) via
determining the defining pairs of all binary characteristic sequences of
cosets, which coincide with the sets of pre-images modulo $p^2$ of each fixed
value of Fermat quotients. From the defining pairs, we can obtain an earlier
result of linear complexity for the binary threshold sequences and a new result
of linear complexity for the Legendre-Fermat quotient sequences under the
assumption of $2^{p-1}\not\equiv 1 \bmod {p^2}$.


title:
First measurement of the small-scale spatial variability of the rain
  drop size distribution: Results from a crucial experiment and maximum entropy
  modeling

abstract:
  The main challenges of measuring precipitation are related to the
spatio-temporal variability of the drop-size distribution, to the uncertainties
that condition the modeling of that distribution, and to the instrumental
errors present in the in situ estimations. This PhD dissertation proposes
advances in all these questions. The relevance of the spatial variability of
the drop-size distribution for remote sensing measurements and
hydro-meteorology field studies is asserted by analyzing the measurement of a
set of disdrometers deployed on a network of 5 squared kilometers. This study
comprises the spatial variability of integral rainfall parameters, the ZR
relationships, and the variations within the one moment scaling method. The
modeling of the drop-size distribution is analyzed by applying the MaxEnt
method and comparing it with the methods of moments and the maximum likelihood.
The instrumental errors are analyzed with a compressive comparison of sampling
and binning uncertainties that affect actual devices. These analysis are
further extended in several appendices where an error analysis is developed and
new studies are proposed. The relevance of the pre-processing of disdrometric
measurements is also assessed. The data-sets evaluated comprise experimental
measurements of the GPM (NASA-JAXA) ground validation satellite mission and
synthetic distributions generated computationally.


title:
Harnack estimates for degenerate parabolic equations modeled on the
  subelliptic p-Laplacian

abstract:
  We establish a Harnack inequality for a class of quasi-linear PDE modeled on
the prototype {equation*}
  \partial_tu= -\sum_{i=1}^{m}X_i^\ast (|\X u|^{p-2} X_i u){equation*} where
$p\ge 2$, $ \ \X = (X_1,..., X_m)$ is a system of Lipschitz vector fields
defined on a smooth manifold $\M$ endowed with a Borel measure $\mu$, and
$X_i^*$ denotes the adjoint of $X_i$ with respect to $\mu$. Our estimates are
derived assuming that (i) the control distance $d$ generated by $\X$ induces
the same topology on $\M$; (ii) a doubling condition for the $\mu$-measure of
$d-$metric balls and (iii) the validity of a Poincar\'e inequality involving
$\X$ and $\mu$. Our results extend the recent work in
\cite{DiBenedettoGianazzaVespri1}, \cite{K}, to a more general setting
including the model cases of (1) metrics generated by H\"ormander vector fields
and Lebesgue measure; (2) Riemannian manifolds with non-negative Ricci
curvature and Riemannian volume forms; and (3) metrics generated by non-smooth
Baouendi-Grushin type vector fields and Lebesgue measure. In all cases the
Harnack inequality continues to hold when the Lebesgue measure is substituted
by any smooth volume form or by measures with densities corresponding to
Muckenhoupt type weights.


title: Harder-Narasimhan filtration for rank 2 tensors and stable coverings

abstract:
  We construct a Harder-Narasimhan filtration for rank $2$ tensors, where there
does not exist any such notion a priori, as coming from a GIT notion of maximal
unstability. The filtration associated to the 1-parameter subgroup of Kempf
giving the maximal way to destabilize, in the GIT sense, a point in the
parameter space of the construction of the moduli space of rank $2$ tensors
over a smooth projective complex variety, does not depend on certain integer
used in the construction of the moduli space, for large values of the integer.
Hence, this filtration is unique and we define the Harder-Narasimhan filtration
for rank $2$ tensors as this unique filtration coming from GIT. Symmetric rank
$2$ tensors over smooth projective complex curves define curve coverings lying
on a ruled surface, hence we can translate the stability condition to define
stable coverings and characterize the Harder-Narasimhan filtration in terms of
intersection theory.


title:
Production of Z' and W' via Drell-Yan processes in the 4D Composite
  Higgs Model at the LHC

abstract:
  We present an analysis of both the Neutral Current (NC) and Charged Current
(CC) Drell-Yan processes at the LHC within a 4 Dimensional realization of a
Composite Higgs model studying the cross sections and taking into account the
possible impact of the extra fermions present in the spectrum.


title: Synchronous Phase Shift at LHC

abstract:
  The electron cloud in vacuum pipes of accelerators of positively charged
particle beams causes a beam energy loss which could be estimated from the
synchronous phase. Measurements done with beams of 75 ns, 50 ns, and 25 ns
bunch spacing in the LHC for some fills in 2010 and 2011 show that the average
energy loss depends on the total beam intensity in the ring. Later measurements
during the scrubbing run with 50 ns beams show the reduction of the electron
cloud due to scrubbing. Finally, measurements of the individual bunch phase
give us information about the electron cloud build-up inside the batch and from
batch to batch.


title: Probing Majorana neutrinos in the regime of the normal mass hierarchy

abstract:
  An approach to developing a feasible neutrinoless double beta decay
experiment capable of probing Majorana masses in the regime of the
nondegenerate normal neutrino mass hierarchy is proposed. For such an
experiment, this study suggests that 130Te is likely the best choice of
candidate isotope and that metal-loaded liquid scintillator likely represents
the best choice of detector technology. An evaluation of the required loading,
scintillator properties and detector configuration is presented. While further
development of Te-loaded liquid scintillator is required, recent progress in
this area suggests that this task may not be insurmountable. This could open
the door for a future experiment of unparalleled sensitivity that might be
accommodated in a volume of the order of 10-20 kilotons. To the best of our
knowledge, this is the first time that a potentially practical experimental
approach to exploring Majorana neutrino masses in the nondegenerate normal
hierarchy has been suggested.


title: SuperB Technical Design Report

abstract:
  In this Technical Design Report (TDR) we describe the SuperB detector that
was to be installed on the SuperB e+e- high luminosity collider. The SuperB
asymmetric collider, which was to be constructed on the Tor Vergata campus near
the INFN Frascati National Laboratory, was designed to operate both at the
Upsilon(4S) center-of-mass energy with a luminosity of 10^{36} cm^{-2}s^{-1}
and at the tau/charm production threshold with a luminosity of 10^{35}
cm^{-2}s^{-1}. This high luminosity, producing a data sample about a factor 100
larger than present B Factories, would allow investigation of new physics
effects in rare decays, CP Violation and Lepton Flavour Violation. This
document details the detector design presented in the Conceptual Design Report
(CDR) in 2007. The R&D and engineering studies performed to arrive at the full
detector design are described, and an updated cost estimate is presented.
  A combination of a more realistic cost estimates and the unavailability of
funds due of the global economic climate led to a formal cancelation of the
project on Nov 27, 2012.


title: Three proofs of the Casas-Alvero conjecture

abstract:
  The Casas-Alvero conjecture is about interpolation polynomials. There are
some partial proofs of it, but there is not any proof in the general case.In
this paper we propose three.


title: The Analytical Assembly Map and Index Theory

abstract:
  In this paper we study the index theoretic interpretation of the analytical
assembly map that appears in the Baum-Connes conjecture. In its general form it
may be constructed using Kasparov's equivariant KK-theory. In the special case
of a torsionfree group the domain simplifies to the usual K-homology of the
classifying space BG of G and it is frequently used that in this case the
analytical assembly map is given by assigning to an operator an equivariant
index. We give a precise formulation of this statement and prove it.


title:
Non-harmonic cones are sets of injectivity for the twisted spherical
  means on $\mathbb C^n$

abstract:
  In this article, we prove that a complex cone is a set of injectivity for the
twisted spherical means for the class of all continuous functions on $\mathbb
C^n$ as long as it does not completely lay on the level surface of any
bi-graded homogeneous harmonic polynomial on $\mathbb C^n.$ Further, we produce
examples of such level surfaces.


title: Large time limit and local L^2-index theorems for families

abstract:
  We compute explicitly, and without any extra regularity assumptions, the
large time limit of the fibrewise heat operator for Bismut-Lott type
superconnections in the L^2-setting. This is motivated by index theory on
certain non-compact spaces (families of manifolds with cocompact group action)
where the convergence of the heat operator at large time implies refined
L^2-index formulas. As applications, we prove a local L^2-index theorem for
families of signature operators and an L^2-Bismut-Lott theorem, expressing the
Becker-Gottlieb transfer of flat bundles in terms of Kamber-Tandeur classes.
With slightly stronger regularity we obtain the respective refined versions: we
construct L^2-eta forms and L^2-torsion forms as transgression forms.


title:
Investigating $\beta$-decay properties of spherical nuclei along the
  possible r-process path

abstract:
  The spherical QRPA method is used for the calculations of the $\beta$-decay
properties of the neutron-rich nuclei in the region near the neutron magic
numbers N=82 and N=126 which are important for determination of the r-process
path. Our calculations differ from previous works by the use of realistic
forces for the proton-neutron interaction. Both the allowed and first-forbidden
$\beta$-decays are included. Detailed comparisons with the experimental
measurements and the previous shell-model calculations are performed. The
results for half-lives and beta-delayed neutron emission probabilities will
serve as input for the r-process nucleosynthesis simulations.


title:
Kazama-Suzuki models and BPS domain wall junctions in N=1 SU(n) Super
  Yang-Mills

abstract:
  Domain walls in N=1 supersymmetric Yang-Mills theory conjecturally support
topological degrees of freedom at low energy. Domain wall junctions are thus
expected to support gapless degrees of freedom. We propose a natural candidate
for the low-energy description of such junctions.


title:
Modular-type functions attached to Calabi-Yau varieties: integrality
  properties

abstract:
  We study the integrality properties of the coefficients of the mirror map
attached to the generalized hypergeometric function $_{n}F_{n-1}$ with rational
parameters and with a maximal unipotent monodromy. We present a conjecture on
the $p$-integrality of the mirror map which can be verified experimentally. We
prove its consequence on the $N$-integrality of the mirror map for the
particular cases $1\leq n\leq 4$.
  For $n=2$ we obtain the Takeuchi's classification of arithmetic triangle
groups with a cusp, and for $n=4$ we prove that $14$ examples of hypergeometric
Calabi-Yau equations are the full classification of hypergeometric mirror maps
with integral coefficients. As a by-product we get the integrality of the
corresponding algebra of modular-type functions. These are natural
generalizations of the algebra of classical modular and quasi-modular forms in
the case $n=2$.


title: Riemann-Hilbert approach to gap probabilities for the Bessel process

abstract:
  We consider the gap probability for the Bessel process in the single-time and
multi-time case. We prove that the scalar and matrix Fredholm determinants of
such process can be expressed in terms of determinants of integrable kernels
\`a la Its-Izergin-Korepin-Slavnov and thus related to suitable Riemann-Hilbert
problems. In the single-time case, we construct a Lax pair formalism and we
derive a Painlev\'e III equation related to the Fredholm determinant.


title:
Observation of in-gap surface states in the Kondo insulator SmB6 by
  photoemission

abstract:
  Kondo insulators (KIs) are strongly correlated materials in which the
interactions between 4f and conduction electrons lead to a hybridization gap
opening at low temperature 1-2. SmB6 is a typical KI, but its resistivity does
not diverge at low temperatures, which was attributed to some in-gap states
3-10. However after several decades of research, the nature and origin of the
in-gap states remain unclear. Recent band calculation and transport
measurements suggest that the in-gap states could actually be ascribed to
topological surface states. SmB6 thus might be the first realization of
topological Kondo insulator (TKI) 13, the strongly correlated version of
topological insulator (TI) 11,12. Here by performing angle-resolved
photoemission spectroscopy (ARPES), we directly observed several dispersive
states within the hybridization gap of SmB6, which cross the Fermi level and
show negligible kz dependence, indicative of their surface origin. Furthermore,
the circular dichroism (CD) ARPES results of the in-gap states suggest the
chirality of orbital momentum, and temperature dependent measurements have
shown that the in-gap states vanish simultaneously with the hybridization gap
around 150 K. These strongly suggest their possible topological origin.


title:
Quantum breathing dynamics of ultracold bosons in 1D-harmonic traps:
  Unraveling the pathway from few- to many-body systems

abstract:
  Following a `bottom-up approach' in understanding many-particle effects and
dynamics we provide a systematic ab initio study of the dependence of the
breathing dynamics of ultracold bosons in a 1D harmonic trap on the number of
bosons ranging from few to many. To this end, we employ the Multi-Layer
Multi-Configuration Time-Dependent Hartree method for Bosons (ML-MCTDHB) which
has been developed very recently [S. Kr\"onke, L. Cao, O. Vendrell and P.
Schmelcher. {\it New J. Phys.} {\bf 15}, 063018 (2013)]. The beating behavior
for two bosons is found numerically and consequently explained by an analytical
approach. Drawing on this, we show how to compute the complete breathing mode
spectrum in this case. We examine how the two-mode breathing behavior of two
bosons evolves to the single-frequency behavior of the many-particle limit when
adding more particles. In the limit of many particles, we numerically study the
dependence of the breathing mode frequency on both the interaction strength as
well as on the particle number. We provide an estimate for the parameter region
in which Gross-Pitaevskii theory is well applicable.


title:
Multi-field nanoindentation apparatus for measuring local mechanical
  properties of materials in external magnetic and electric fields

abstract:
  Nano/micro-scale mechanical properties of multiferroic materials can be
controlled by the external magnetic or electric field due to the coupling
interaction. For the first time, a modularized multi-field nanoindentation
apparatus for carrying out testing on materials in external
magnetostatic/electrostatic field is constructed. Technical issues, such as the
application of magnetic/electric field and the processes to diminish the
interference between external fields and the other parts of the apparatus, are
addressed. Tests on calibration specimen indicate the feasibility of the
apparatus. The load-displacement curves of ferromagnetic, ferroelectric and
magnetoelectric materials in the presence/absence of external fields reveal the
small-scale magnetomechanical and electromechanical coupling, showing as the
Delta-E and Delta-H effects, i.e. the magnetic/electric field induced changes
in the apparent elastic modulus and indentation hardness.


title: Using Genetic Programming to Model Software

abstract:
  We study a generic program to investigate the scope for automatically
customising it for a vital current task, which was not considered when it was
first written. In detail, we show genetic programming (GP) can evolve models of
aspects of BLAST's output when it is used to map Solexa Next-Gen DNA sequences
to the human genome.


title: Dynamical Gauge Symmetry Breaking in Strongly Coupled Lattice Theories

abstract:
  We show how a strongly coupled lattice theory consisting of just fermions and
gauge fields can exhibit a dynamical Higgs mechanism through the formation of a
gauge invariant four fermion condensate. Furthermore, we argue that this
lattice Higgs phase may survive into the continuum limit.


title:
MMTF Discovery of Giant Ionization Cones in MR 2251-178: Implications
  for Quasar Radiative Feedback

abstract:
  We report the discovery of giant ionization cones in the 140-kpc nebula
around quasar MR 2251-178 based on deep [O III] 5007/H-beta and [N II]
6583/H-alpha flux ratio maps obtained with the Maryland-Magellan Tunable Filter
(MMTF) on the Baade-Magellan 6.5m telescope. These cones are aligned with the
weak double-lobed radio source observed on smaller scale <30 kpc). They have an
opening angle ~120deg +/- 10deg and subtend ~65-90% of 4pi steradians, where
the large uncertainty takes into account possible projection effects. The
material in the outer ionization cones is matter-bounded, indicating that all
ionizing photons emitted through the cones escape from the system. The quasar
ionizing flux is ~2-3 times fainter outside of these cones, despite the largely
symmetric geometry of the nebula in [O III]. Overall, adding up the
contributions from both inside and outside the cones, we find that ~65-95% of
the quasar ionizing radiation makes its way out of the system. These results
emphasize the need for line ratio maps to quantify the escape fraction of
ionizing radiation from quasars and the importance of quasar radiative feedback
on the intergalactic medium.


title: Modular discretization of the AdS2/CFT1 Holography

abstract:
  We propose a finite discretization for the black hole geometry and dynamics.
We realize our proposal, in the case of extremal black holes, for which the
radial and temporal near horizon geometry is known to be
AdS$_2=SL(2,\mathbb{R})/SO(1,1,\mathbb{R})$. We implement its discretization by
replacing the set of real numbers $\mathbb{R}$ with the set of integers modulo
$N$, with AdS$_2$ going over to the finite geometry
AdS$_2[N]=SL(2,\mathbb{Z}_N)/SO(1,1,\mathbb{Z}_N)$.
  We model the dynamics of the microscopic degrees of freedom by generalized
Arnol'd cat maps, ${\sf A}\in SL(2,\mathbb{Z}_N)$, which are isometries of the
geometry at both the classical and quantum levels.
  These exhibit well studied properties of strong arithmetic chaos, dynamical
entropy, nonlocality and factorization in the cutoff discretization $N$, which
are crucial for fast quantum information processing.
  We construct, finally, a new kind of unitary and holographic correspondence,
for AdS$_2[N]$/CFT$_1[N]$, via coherent states of both the bulk and boundary
geometries.


title: Identifying Symmetry-Protected Topological Order by Entanglement Entropy

abstract:
  According to the classification using projective representations of the SO(3)
group, there exist two topologically distinct gapped phases in spin-1 chains.
The symmetry-protected topological (SPT) phase possesses half-integer
projective representations of the SO(3) group, while the trivial phase
possesses integer linear representations. In the present work, we implement
non-Abelian symmetries in the density matrix renormalization group (DMRG)
method, allowing us to keep track of (and also control) the virtual bond
representations, and to readily distinguish the SPT phase from the trivial one
by evaluating the multiplet entanglement spectrum. In particular, using the
entropies $S^I$ ($S^H$) of integer (half-integer) representations, we can
define an entanglement gap $G = S^I - S^H$, which equals 1 in the SPT phase,
and $-1$ in the trivial phase. As application of our proposal, we study the
spin-1 models on various 1D and quasi-1D lattices, including the
bilinear-biquadratic model on the single chain, and the Heisenberg model on a
two-leg ladder and a three-leg tube. Among others, we confirm the existence of
an SPT phase in the spin-1 tube model, and reveal that the phase transition
between the SPT and the trivial phase is a continuous one. The transition point
is found to be critical, with conformal central charge $c=3$ determined by fits
to the block entanglement entropy.


title:
Generalized Fractional Order Derivatives, Its Properties and
  Applications

abstract:
  The concept of fractional order derivative can be found in extensive range of
many different subject areas. For this reason, the concept of fractional order
derivative should be examined. After giving different methods mostly used in
engineering and scientific applications, the omissions or errors of these
methods will be discussed in this study. The mostly used methods are Euler,
Riemann-Liouville and Caputo which are fractional order derivatives. The
applications of these methods to constant and identity functions will be given
in this study. Obtained results demonstrated that all of three methods have
errors and deficiencies. In fact, the obtained results demonstrated that the
methods given as fractional order derivatives are curve fitting methods or
curve approximation methods. In this paper, we redefined fractional order
derivative (FOD) by using classical derivative definition and L Hospital
method, since classical derivative definition concluded in indefinite limit
such as 0/0. The obtained definition is same as classical derivative definition
in case of fractional order is equal to 1. This implies that definitions and
theorems in this paper sound and complete.
  After defining the FOD concept, the applications of FOD for polynomial,
exponential, trigonometric and logarithmic functions were handled in this
study. The properties of FOD for positive monotonic increasing/decreasing
functions were demonstrated in this paper. Another important point is that the
relation between derivatives and complex functions were also verified in this
paper.


title:
Modulation of conductance and superconductivity by top-gating in
  LaAlO3/SrTiO3 2-dimensional electron systems

abstract:
  We report the electrical top-gating of a 2-dimensional electron gas (2DEG)
formed at the LaAlO3/SrTiO3 interface, using electron-beam evaporated Au gate
electrodes. In these structures, epitaxial LaAlO3 films grown by pulsed laser
deposition induce the 2DEGs at the interface to the SrTiO3 substrate and
simultaneously act as the gate dielectric. The structured top-gates enable a
local tuning and complete on/off switching of the interface
(super)-conductivity, while maintaining the usual, intrinsic characteristics
for these LaAlO3/SrTiO3 interfaces when no gate voltage is applied.


title: Robustness of strong stability of semigroups

abstract:
  In this paper we study the preservation of strong stability of strongly
continuous semigroups on Hilbert spaces. In particular, we study a situation
where the generator of the semigroup has a finite number of spectral points on
the imaginary axis and the norm of its resolvent operator is polynomially
bounded near these points. We characterize classes of finite rank perturbations
preserving the strong stability of the semigroup. In addition, we improve
recent results on preservation of polynomial stability of a semigroup under
finite rank perturbations of its generator. Theoretic results are illustrated
with an example where we consider the preservation of the strong stability of a
multiplication semigroup.


title:
Observation of the Dependence of Scintillation from Nuclear Recoils in
  Liquid Argon on Drift Field

abstract:
  We have exposed a dual-phase Liquid Argon Time Projection Chamber (LAr-TPC)
to a low energy pulsed narrowband neutron beam, produced at the Notre Dame
Institute for Structure and Nuclear Astrophysics to study the scintillation
light yield of recoiling nuclei in a LAr-TPC. A liquid scintillation counter
was arranged to detect and identify neutrons scattered in the LAr-TPC target
and to select the energy of the recoiling nuclei.
  We report the observation of a significant dependence on drift field of
liquid argon scintillation from nuclear recoils of 11 keV. This observation is
important because, to date, estimates of the sensitivity of noble liquid TPC
dark matter searches are based on the assumption that electric field has only a
small effect on the light yield from nuclear recoils.


title:
Morphological instabilities of stratified epithelia: a mechanical
  instability in tumour formation

abstract:
  Interfaces between stratified epithelia and their supporting stromas commonly
exhibit irregular shapes. Undulations are particularly pronounced in dysplastic
tissues and typically evolve into long, finger-like protrusions in carcinomas.
In a previous work (Basan et al., Phys. Rev. Lett. 106, 158101 (2011)), we
demonstrated that an instability arising from viscous shear stresses caused by
the constant flow due to cell turnover in the epithelium could drive this
phenomenon. While interfacial tension between the two tissues as well as
mechanical resistance of the stroma tend to maintain a flat interface, an
instability occurs for sufficiently large viscosity, cell-division rate and
thickness of the dividing region in the epithelium. Here, extensions of this
work are presented, where cell division in the epithelium is coupled to the
local concentration of nutrients or growth factors diffusing from the stroma.
This enhances the instability by a mechanism similar to that of the
Mullins-Sekerka instability in single-diffusion processes of crystal growth. We
furthermore present the instability for the generalized case of a viscoelastic
stroma.

categories: physics.bio-ph cond-mat.soft physics.flu-dyn physics.med-ph q-bio.TO


title:
OMG: How Much Should I Pay Bob in Truthful Online Mobile Crowdsourced
  Sensing?

abstract:
  Mobile crowdsourced sensing (MCS) is a new paradigm which takes advantage of
the pervasive smartphones to efficiently collect data, enabling numerous novel
applications. To achieve good service quality for a MCS application, incentive
mechanisms are necessary to attract more user participation. Most of existing
mechanisms apply only for the offline scenario where all users' information are
known a priori. On the contrary, we focus on a more real scenario where users
arrive one by one online in a random order. We model the problem as an online
auction in which the users submit their private types to the crowdsourcer over
time, and the crowdsourcer aims to select a subset of users before a specified
deadline for maximizing the total value of the services provided by selected
users under a budget constraint. We design two online mechanisms, OMZ and OMG,
satisfying the computational efficiency, individual rationality, budget
feasibility, truthfulness, consumer sovereignty and constant competitiveness
under the zero arrival-departure interval case and a more general case,
respectively. Through extensive simulations, we evaluate the performance and
validate the theoretical properties of our online mechanisms.


title: A Temporal Logic of Security

abstract:
  A new logic for verification of security policies is proposed. The logic,
HyperLTL, extends linear-time temporal logic (LTL) with connectives for
explicit and simultaneous quantification over multiple execution paths, thereby
enabling HyperLTL to express information-flow security policies that LTL
cannot. A model-checking algorithm for a fragment of HyperLTL is given, and the
algorithm is implemented in a prototype model checker. The class of security
policies expressible in HyperLTL is characterized by an arithmetic hierarchy of
hyperproperties.


title: Goos-Hanchen like Shifts in Graphene Double Barriers

abstract:
  We study the Goos-Hanchen like shifts for Dirac fermions in graphene
scattered by double barrier structures. After obtaining the solution for the
energy spectrum, we use the boundary conditions to explicitly determine the
Goos-Hanchen like shifts and the associated transmission probability. We
analyze these two quantities at resonances by studying their {main}
characteristics as a function of the energy and electrostatic potential
parameters. To check the validity of our computations we recover previous
results obtained for a single barrier under appropriate limits.


title:
Oscillatory features in the curvature power spectrum after a sudden turn
  of the inflationary trajectory

abstract:
  In the context of two-field inflation characterized by a light direction and
a heavy direction, we revisit the question of the impact of the massive modes
on the power spectrum produced after a turn in the inflationary trajectory. We
consider in particular the resonant effect due to the background oscillations
following a sharp turn. Working in the mass basis, i.e. in the basis spanned by
the eigenvectors of the effective mass matrix for the perturbations, we provide
an analytical estimate of the resonant effect, using the in-in formalism. In
comparison with earlier estimates, we find the same the spectral dependence but
a smaller amplitude. We also compute, again via the in-in formalism, the effect
of the direct coupling between the light and heavy modes at the instant of the
turn and confirm our previous results obtained via a different method.


title: Coupled-cluster studies of infinite nuclear matter

abstract:
  The aim of this work is to develop the relevant formalism for performing
coupled-cluster (CC) calculations in nuclear matter and neutron star matter,
including thereby important correlations to infinite order in the interaction
and testing modern nuclear forces based on chiral effective field theory. Our
formalism includes the exact treatment of the so-called Pauli operator in a
partial wave expansion of the equation of state. Nuclear and neutron matter
calculations are done using a coupled particle-particle and hole-hole ladder
approximation. The coupled ladder equations are derived as an approximation of
CC theory, leaving out particle-hole and non-linear diagrams from the CC
doubles amplitude equation. This study is a first step toward CC calculations
for nuclear and neutron matter. We present results for both symmetric nuclear
matter and pure neutron matter employing state-of-the-art nucleon-nucleon
interactions based on chiral effective field theory. We employ also the newly
optimized chiral interaction [A. Ekstr\"om et al., Phys. Rev. Lett. 110, 192502
(2013)] to study infinite nuclear matter. The ladder approximation method and
corresponding results are compared with conventional Brueckner-Hartree-Fock
theory.


title: Differential hierarchy and additional grading of knot polynomials

abstract:
  Colored knot polynomials possess a peculiar Z-expansion in certain
combinations of differentials, which depends on the representation. The
coefficients of this expansion are functions of the three variables (A,q,t) and
can be considered as new distinguished coordinates on the space of knot
polynomials, analogous to the coefficients of alternative character expansion.
These new variables are decomposed in an especially simple way, when the
representation is embedded into a product of the fundamental ones. The fourth
grading recently proposed in arXiv:1304.3481, seems to be just a simple
redefinition of these new coordinates, elegant but in no way distinguished. If
so, it does not provide any new independent knot invariants, instead it can be
considered as one more testimony of the hidden differential hierarchy
(Z-expansion) structure behind the knot polynomials.


title: Lie groupoids and crossed module-valued gerbes over stacks

abstract:
  We give a precise and general description of gerbes valued in arbitrary
crossed module and over an arbitrary differential stack. We do it using only
Lie groupoids, hence ordinary differential geometry. We prove the coincidence
with the existing notions by comparing our construction with non-Abelian
cohomology.


title:
New Large-Rank Nichols Algebras Over Nonabelian Groups With Commutator
  Subgroup Z_2

abstract:
  In this article, we explicitly construct new finite-dimensional,
link-indecomposable Nichols algebras with Dynkin diagrams of type
An,Cn,Dn,E6,E7,E8,F4 over any group G with commutator subgroup isomorphic to
Z_2.The construction is generic in the sense that the type just depends on the
rank and center of G, and thus positively answers for all groups of this class
a question raised by Susan Montgomory in 1995 [Mont95][AS02].
  Our construction uses the new notion of a covering Nichols algebra as a
special case of a covering Hopf algebra [Len12] and produces non-faithful
Nichols algebras. However, we give faithful examples of Doi twists for type
A3,C3,D4,F4 over several nonabelian groups of order 16 and 32. These are hence
the first known examples of faithful, finite-dimensional, link-indecomposable
Nichols algebras of rank >2 over nonabelian groups.


title: $p$-adic Hodge theory in rigid analytic families

abstract:
  We study the functors $\D_{\B_\ast}(V)$, where $\B_\ast$ is one of Fontaine's
period rings and $V$ is a family of Galois representations with coefficients in
an affinoid algebra $A$. We show that
$\D_{\HT}(V)=\oplus_{i\in\Z}(\D_{\Sen}(V)\cdot t^i)^{\Gamma_K}$,
$\D_{\dR}(V)=\D_{\dif}(V)^{\Gamma_K}$, and
$\D_{\cris}(V)=\D_{\rig}(V)[1/t]^{\Gamma_K}$, generalizing results of Sen,
Fontaine, and Berger. The modules $\D_{\HT}(V)$ and $\D_{\dR}(V)$ are coherent
sheaves on $\Sp(A)$, and $\Sp(A)$ is stratified by the ranks of submodules
$\D_{\HT}^{[a,b]}(V)$ and $\D_{\dR}^{[a,b]}(V)$ of "periods with Hodge-Tate
weights in the interval $[a,b]$". Finally, we construct functorial
$\B_\ast$-admissible loci in $\Sp(A)$, generalizing a result of Berger-Colmez
to the case where $A$ is not necessarily reduced.


title:
Quantum Hall criticality and localization in graphene with short-range
  impurities at the Dirac point

abstract:
  We explore the longitudinal conductivity of graphene at the Dirac point in a
strong magnetic field with two types of short-range scatterers: adatoms that
mix the valleys and "scalar" impurities that do not mix them. A scattering
theory for the Dirac equation is employed to express the conductance of a
graphene sample as a function of impurity coordinates; an averaging over
impurity positions is then performed numerically. The conductivity $\sigma$ is
equal to the ballistic value $4e^2/\pi h$ for each disorder realization
provided the number of flux quanta considerably exceeds the number of
impurities. For weaker fields, the conductivity in the presence of scalar
impurities scales to the quantum-Hall critical point with $\sigma \simeq 4
\times 0.4 e^2/h$ at half filling or to zero away from half filling due to the
onset of Anderson localization. For adatoms, the localization behavior is
obtained also at half filling due to splitting of the critical energy by
intervalley scattering. Our results reveal a complex scaling flow governed by
fixed points of different symmetry classes: remarkably, all key manifestations
of Anderson localization and criticality in two dimensions are observed
numerically in a single setup.


title: Comparing Some Nucleon-Nucleon Potentials

abstract:
  The aim is to compare a few Nucleon-Nucleon (NN) potentials especially
Reid68, Reid68-Day, Reid93, UrbanaV14, ArgonneV18, Nijmegen 93, Nijmegen I and
Nijmegen II. Although these potentials have some likenesses and are almost
phenomenological, they include in general different structures and their own
characteristics. The potentials are constructed in a manner that fit the NN
scattering data or phase shifts and are compared in this way. A high-quality
scale of a potential is that it fits the data with $\chi^{2}/N_{data} \approx
1$, describes well the deuteron properties and gives satisfactory results in
nuclear-structure calculations. However, these scales have some failures. Here,
we first compare many potentials by confronting them with the data. Then, we
try to compare the potential forms by considering the potential structures
directly and therefore regarding their substantial bases somehow. To do so, we
note that since the potentials are written in different schemas, it is
necessary to write them in a unique schema. On the other hand, because three
major terms in the NN interaction are central, tensor and spin-orbit terms; so,
to perform a reduction plan and arrive at a common structure, we choose the
Reid's potential form. Next, we compare the potentials for some states and
address some other related issues as well.


title: Tree-irreducible automorphisms of free groups

abstract:
  We introduce a new class of automorphisms $\varphi$ of the non-abelian free
group $F_N$ of finite rank $N \geq 2$ which contains all iwips (= fully
irreducible automorphisms), but also any automorphism induced by a
pseudo-Anosov homeomorphism of a surface with arbitrary many boundary
components. More generally, there may be subgroups of $F_N$ of rank $\geq 2$ on
which $\varphi$ restricts to the identity.
  We prove some basic facts about such {\em tree-irreducible} automorphisms,
and show that, together with Dehn twist automorphisms, they are the natural
basic building blocks from which any automorphism of $\FN$ can be constructed
in a train track set-up. We then show:
  {\bf Theorem:} {\it Every tree-irreducible automorphism of $F_N$ has induced
North-South dynamics on the Thurston compactification $\bar{\rm CV}_N$ of Outer
space.}
  Finally, we define a "blow-up" construction on the vertices of a train track
map, which, starting from iwips, produces tree-irreducible automorphisms which
in general are not iwip.


title: Spectral asymmetry of the massless Dirac operator on a 3-torus

abstract:
  Consider the massless Dirac operator on a 3-torus equipped with Euclidean
metric and standard spin structure. It is known that the eigenvalues can be
calculated explicitly: the spectrum is symmetric about zero and zero itself is
a double eigenvalue. The aim of the paper is to develop a perturbation theory
for the eigenvalue with smallest modulus with respect to perturbations of the
metric. Here the application of perturbation techniques is hindered by the fact
that eigenvalues of the massless Dirac operator have even multiplicity, which
is a consequence of this operator commuting with the antilinear operator of
charge conjugation (a peculiar feature of dimension 3). We derive an asymptotic
formula for the eigenvalue with smallest modulus for arbitrary perturbations of
the metric and present two particular families of Riemannian metrics for which
the eigenvalue with smallest modulus can be evaluated explicitly. We also
establish a relation between our asymptotic formula and the eta invariant.


title:
Modifying the Entity relationship modelling notation: towards high
  quality relational databases from better notated ER models

abstract:
  The entity relationship modelling using the original ER notation has been
applauded providing a natural view of data in conceptual modelling of
information systems. However, the current ER to relational model transformation
algorithm is known to be insufficient in providing a complete and accurate
representation of the ER model undertaken for transformation. In an effort to
derive better transformations from ER models, we have understood that
modifications should be introduced to both of the existing transformation
algorithm as well as to the ER notation. Introducing some new concepts, we have
adapted the original ER notation and developed a new transformation algorithm
based on the existing one. This paper presents the modified ER notation with an
ER diagram drawn based on the new notation.


title: Height of motives

abstract:
  We define the height of a motive over a number field. We show that if we
assume the finiteness of motives of bounded height, Tate conjecture for the
$p$-adic Tate module can be proved for motives with good reduction at $p$.


title: The Martingale Representation Theorem and Clark-Ocone formula

abstract:
  In this paper we explore the fundamentals of the Martingale Representation
Theorem (MRT) and a closely related result, the Clark-Ocone formula. We also
investigate how far these theorems can be taken, notably beyond the regular
Sobolev spaces, through changes of measures and enlargement of filtrations. We
look at Brownian motion (B.M.) driven continuous martingales as well as Jump
and Levy process-driven martingales.


title: Heights of mixed motives

abstract:
  We define the height of a mixed motive over a number field extending our
previous work for pure motives.


title:
Spherically Symmetric Solutions in F(R) Gravity and Gravitational
  Repulsion

abstract:
  Spherically symmetric solutions in F(R) theories in astronomical systems with
rising energy density are studied. The range of parameters is established for
which the flat space-time approximation for the background metric is valid. For
the solutions in which the curvature scalar oscillates with large amplitude and
high frequency, found in our previous papers, it is shown that the analysis of
the Jeans instability is strongly modified. It is discovered that for large
astronomical objects modified gravity can be repulsive, so such objects shrink
forming relatively thin shells instead of quasi uniform bodies. This may
explain the formation of cosmic voids.


title: Measuring the tth coupling from SSDL+2b measurements

abstract:
  We evaluate the potential of a dedicated search for tth production in the
SSDL+2b channel. Such a measurement provides direct access to the top Yukawa
coupling, since the sensitivity is not convolved with the loop-level
h-gamma-gamma or poorly known hbb coupling, as is the case for present tth
searches. Furthermore, susceptibility to uncertainties in the Higgs width can
be reduced by considering a ratio of SSDL+2b rates with those of the performed
Wh -> WWW* measurement. The SSDL channel can therefore rely primarily on the
already well-measured h->WW* decay. This feasibility study required the
development of a new calculation method for "fake" leptons, which constitute
the dominant background to our search. Combining measurements from LHC7, LHC8
and in the future LHC14 for the Higgs coupling fit would help resolve any
remaining ambiguity between the top Yukawa coupling and a BSM contribution to
the hgg coupling.


title: Dual automorphisms of free groups

abstract:
  For any choice of a basis $\cal A$ the free group $F_N$ of finite rank $N
\geq 2$ can be canonically identified with the set $F(\cal A)$ of reduced words
in $\cal A\cup \cal A^{-1}$. However, such a word $w \in F(\cal A)$ admits a
second interpretation, namely as cylinder $C^1_w \subset \partial F_N$. The
subset of $\partial F_N$ defined by $C^1_w$ depends not only on the element of
$F_N$ given by the word $w$, but also on the chosen basis $\cal A$. In
particular one has in general, for $\Phi \in \Aut(F_N)$: $$\Phi(C^1_w) \neq
C^1_{\Phi(w)}$$ Indeed, the image of a cylinder under an automorphism $\Phi \in
\Aut(F_N)$ is in general not a cylinder, but a finite union of cylinders:
$$\Phi (C^1_w)=C^{1}_U := \bigcup_{u_i \in U} C^1_{u_i}$$ In his thesis the
first author has given an efficient algorithm and a formula how to determine
such a (uniquely determined) finite {\em reduced} set $U = U(w) \subset F_N$.
We use those to define the dual automorphism $\Phi_{\cal A}^*$ by setting
$\Phi_{\cal A}^*(w) = U(w)$.
  \smallskip \noindent {\bf Theorem:} {\it For any $\Phi \in \Aut(F_N)$ there
are at most 2N distinct finite subsets $U_i \subset F_N$ such that for any $w =
y_1 ... y_r \in F_A$ there is one of them, say $U_{i(w)}$, with $$\Phi_{\cal
A}^*(w) = \Phi(w) U_{i(w)}\, ,$$ and $U_{i(w)}$ depends only on the last letter
$y_r \in \CA \cup \CA^{-1}$. Furthermore, the seize of each $U_{i}$ is bounded
by $2^t$, where $t \geq 0$ is the number of Nielsen automorphisms in any
decomposition of $\Phi$ as product of basis permutations, basis inversions and
elementary Nielsen automorphisms.}


title: Dynamical Black Holes: Approach to the Final State

abstract:
  Since black holes can be formed through widely varying processes, the horizon
structure is highly complicated in the dynamical phase. Nonetheless, as
numerical simulations show, the final state appears to be universal, well
described by the Kerr geometry. How are all these large and widely varying
deviations from the Kerr horizon washed out? To investigate this issue, we
introduce a well-suited notion of horizon multipole moments and equations
governing their dynamics, thereby providing a coordinate and slicing
independent framework to investigate the approach to equilibrium. In
particular, our flux formulas for multipoles can be used as analytical checks
on numerical simulations and, in turn, the simulations could be used to fathom
possible universalities in the way black holes approach their final
equilibrium.


title: Cosmic microwave background anomalies in an open universe

abstract:
  We argue that the observed large-scale cosmic microwave anomalies, discovered
by WMAP and confirmed by the Planck satellite, are most naturally explained in
the context of a marginally-open universe. Particular focus is placed on the
dipole power asymmetry, via an open universe implementation of the large-scale
gradient mechanism of Erickcek et al. Open inflation models, which are
motivated by the string landscape and which can excite `super-curvature'
perturbation modes, can explain the presence of a very-large-scale perturbation
that leads to a dipole modulation of the power spectrum measured by a typical
observer. We provide a specific implementation of the scenario which appears
compatible with all existing constraints.


title: SO(10) as a Framework for Natural Supersymmetry

abstract:
  We consider an SO(10) grand unified theory in which the ratio of the SU(2)_W
and SU(3)_c gaugino masses satisfy M_2/M_3 \approx 3, which results in the
realization of natural supersymmetry. In the MSSM parameter space this relation
looks artificial, but in the SO(10) case it results from a field with a
designated vacuum expectation value. We consider two models, namely
M_1:M_2:M_3=-1/5:3:1 (Case I), and M_1:M_2:M_3=-5:3:1 (Case II). Focusing on
ameliorating the little hierarchy problem, we explore the parameter space of
these models which yield small fine-tuning measuring parameters (natural
supersymmetry) at the electroweak scale (\Delta_{EW}) as well as at the high
scale (\Delta_{HS}). Although both models allow for the solution of the little
hierarchy problem, the predicted sparticle spectra can differ markedly in the
two cases. Depending on the ratio of the bino mass to the other gaugino masses,
Case I leads to stau lepton masses of around a 100 GeV, while in Case II, the
stau slepton masses are in the several TeV range. In Case I, the bino-like
neutralino can be as light as 90 GeV, while the gluino is heavier than 2 TeV or
so. In Case II, due to gluino-bino near degeneracy, the bino cannot be lighter
than a TeV or so. Having a light neutralino with sizable bino-higgsino mixture
in Case I allows the direct dark matter search experiments to test this class
of models.


title:
Radiation Transport for Explosive Outflows: A Multigroup Hybrid Monte
  Carlo Method

abstract:
  We explore Implicit Monte Carlo (IMC) and Discrete Diffusion Monte Carlo
(DDMC) for radiation transport in high-velocity outflows with structured
opacity. The IMC method is a stochastic computational technique for nonlinear
radiation transport. IMC is partially implicit in time and may suffer in
efficiency when tracking Monte Carlo particles through optically thick
materials. DDMC accelerates IMC in diffusive domains. Abdikamalov extended IMC
and DDMC to multigroup, velocity-dependent transport with the intent of
modeling neutrino dynamics in core-collapse supernovae. Densmore has also
formulated a multifrequency extension to the originally grey DDMC method. We
rigorously formulate IMC and DDMC over a high-velocity Lagrangian grid for
possible application to photon transport in the post-explosion phase of Type Ia
supernovae. This formulation includes an analysis that yields an additional
factor in the standard IMC-to-DDMC spatial interface condition. To our
knowledge the new boundary condition is distinct from others presented in prior
DDMC literature. The method is suitable for a variety of opacity distributions
and may be applied to semi-relativistic radiation transport in simple fluids
and geometries. Additionally, we test the code, called SuperNu, using an
analytic solution having static material, as well as with a manufactured
solution for moving material with structured opacities. Finally, we demonstrate
with a simple source and 10 group logarithmic wavelength grid that IMC-DDMC
performs better than pure IMC in terms of accuracy and speed when there are
large disparities between the magnitudes of opacities in adjacent groups. We
also present and test our implementation of the new boundary condition.


title: Factorization of Dirac Equation in Two Space Dimensions

abstract:
  We present a systematic approach for the separation of variables for the
two-dimensional Dirac equation in polar coordinates. The three vector
potential, which couple to the Dirac spinor via minimal coupling, along with
the scalar potential are chosen to have angular dependence which emanate the
Dirac equation to complete separation of variables. Exact solutions are
obtained for a class of solvable potentials along with their relativistic
spinor wavefunctions. Particular attention is paid to the situation where the
potentials are confined to a quantum dot region and are of scalar, vector and
pseudo-scalar type. The study of a single charged impurity embedded in a 2D
Dirac equation in the presence of a uniform magnetic field was treated as a
particular case of our general study.

categories: math-ph cond-mat.mes-hall hep-th math.MP quant-ph


title:
Modeling The Stable Operating Envelope For Partially Stable Combustion
  Engines Using Class Imbalance Learning

abstract:
  Advanced combustion technologies such as homogeneous charge compression
ignition (HCCI) engines have a narrow stable operating region defined by
complex control strategies such as exhaust gas recirculation (EGR) and variable
valve timing among others. For such systems, it is important to identify the
operating envelope or the boundary of stable operation for diagnostics and
control purposes. Obtaining a good model of the operating envelope using
physics becomes intractable owing to engine transient effects. In this paper, a
machine learning based approach is employed to identify the stable operating
boundary of HCCI combustion directly from experimental data. Owing to imbalance
in class proportions in the data, two approaches are considered. A re-sampling
(under-sampling, over-sampling) based approach is used to develop models using
existing algorithms while a cost-sensitive approach is used to modify the
learning algorithm without modifying the data set. Support vector machines and
recently developed extreme learning machines are used for model development and
results compared against linear classification methods show that cost-sensitive
versions of ELM and SVM algorithms are well suited to model the HCCI operating
envelope. The prediction results indicate that the models have the potential to
be used for predicting HCCI instability based on sensor measurement history.


title: Angular momentum and disk evolution in very low mass systems

abstract:
  This review summarises recent observational results regarding the evolution
of angular momentum and disks in brown dwarfs. The observations clearly show
that brown dwarfs beyond ages of 10 Myr are exclusively fast rotators and do
not spin down with age. This suggests that rotational braking by magnetic winds
becomes very inefficient or ceases to work in the substellar regime. There is,
however, some evidence for braking by disks during the first few Myrs in the
evolution, similar to stars. Brown dwarf disks turn out to be scaled down
versions of circumstellar disks, with dust settling, grain growth, and in some
cases cleared out inner regions. The global disk properties roughly scale with
central object mass. The evolutionary timescales in substellar disks are
entirely consistent with what is found for stars, which may be challenging to
understand. Given these findings, it is likely that brown dwarfs are able to
form miniature planetary systems.


title: Decomposition and terapascal phases of water ice

abstract:
  Computational searches for stable and metastable structures of water ice and
other H:O compositions at TPa pressures have led us to predict that H$_2$O
decomposes into H$_2$O$_2$ and a hydrogen-rich phase at pressures of a little
over 5 TPa. The hydrogen-rich phase is stable over a wide range of hydrogen
contents, and it might play a role in the erosion of the icy component of the
cores of gas giants as H$_2$O comes into contact with hydrogen. Metallization
of H$_2$O is predicted at a higher pressure of just over 6 TPa, and therefore
H$_2$O does not have a thermodynamically stable low-temperature metallic form.
We have also found a new and rich mineralogy of complicated water ice phases
which are more stable in the pressure range 0.8--2 TPa than any predicted
previously.


title: Computational Dynamic Market Risk Measures in Discrete Time Setting

abstract:
  Different approaches to defining dynamic market risk measures are available
in the literature. Most are focused or derived from probability theory,
economic behavior or dynamic programming. Here, we propose an approach to
define and implement dynamic market risk measures based on recursion and state
economy representation. The proposed approach is to be implementable and to
inherit properties from static market risk measures.


title:
Nonclassical light in coupled optical systems: anomalous power
  distribution, Fock space dynamics and supersymmetry

abstract:
  We investigate the dynamics of nonclassical states of light in coupled
optical structures and we demonstrate a number of intriguing features
associated with such arrangements. By diagonalizing the system's Hamiltonian,
we show that these geometries can support eigenstates having anomalous optical
intensity distribution with no classical counterpart. These features may
provide new avenues towards manipulating light flow at the quantum level. By
projecting the Hamiltonian operator on Hilbert subspaces spanning different
numbers of photon excitations, we demonstrate that processes such as coherent
transport, state localization and surface Bloch oscillations can take place in
Fock space. Furthermore, we show that Hamiltonian representations of Fock space
manifolds differing by one photon obey a discrete supersymmetry relation


title:
Synthesizing Manipulation Sequences for Under-Specified Tasks using
  Unrolled Markov Random Fields

abstract:
  Many tasks in human environments require performing a sequence of navigation
and manipulation steps involving objects. In unstructured human environments,
the location and configuration of the objects involved often change in
unpredictable ways. This requires a high-level planning strategy that is robust
and flexible in an uncertain environment. We propose a novel dynamic planning
strategy, which can be trained from a set of example sequences. High level
tasks are expressed as a sequence of primitive actions or controllers (with
appropriate parameters). Our score function, based on Markov Random Field
(MRF), captures the relations between environment, controllers, and their
arguments. By expressing the environment using sets of attributes, the approach
generalizes well to unseen scenarios. We train the parameters of our MRF using
a maximum margin learning method. We provide a detailed empirical validation of
our overall framework demonstrating successful plan strategies for a variety of
tasks.


title: Blocks in cycles and k-commuting permutations

abstract:
  Let $k$ be a nonnegative integer, and let $\alpha$ and $\beta$ be two
permutations of $n$ symbols. We say that $\alpha$ and $\beta$ $k$-commute if
$H(\alpha\beta, \beta\alpha)=k$, where $H$ denotes the Hamming metric between
permutations. In this paper, we consider the problem of finding the
permutations that $k$-commute with a given permutation. Our main result is a
characterization of permutations that $k$-commute with a given permutation
$\beta$ in terms of blocks in cycles in the decomposition of $\beta$ as a
product of disjoint cycles. Using this characterization, we provide formulas
for the number of permutations that $k$-commute with a transposition, a
fixed-point free involution and an $n$-cycle, for any $k$. Also, we determine
the number of permutations that $k$-commute with any given permutation, for $k
\leq 4$.


title: Physical Principles for Scalable Neural Recording

abstract:
  Simultaneously measuring the activities of all neurons in a mammalian brain
at millisecond resolution is a challenge beyond the limits of existing
techniques in neuroscience. Entirely new approaches may be required, motivating
an analysis of the fundamental physical constraints on the problem. We outline
the physical principles governing brain activity mapping using optical,
electrical,magnetic resonance, and molecular modalities of neural recording.
Focusing on the mouse brain, we analyze the scalability of each method,
concentrating on the limitations imposed by spatiotemporal resolution, energy
dissipation, and volume displacement. We also study the physics of powering and
communicating with microscale devices embedded in brain tissue.


title: Cyclically presented modules, projective covers and factorizations

abstract:
  We investigate projective covers of cyclically presented modules,
characterizing the rings over which every cyclically presented module has a
projective cover as the rings $R$ that are Von Neumann regular modulo their
Jacobson radical $J(R)$ and in which idempotents can be lifted modulo $J(R)$.
Cyclically presented modules naturally appear in the study of factorizations of
elements in non-necessarily commutative integral domains. One of the possible
applications is to the modules $M_R$ whose endomorphism ring $E:=(M_R)$ is Von
Neumann regular modulo $J(E)$ and in which idempotents lift modulo $J(E)$.


title: Entanglement negativity and topological order

abstract:
  We use the entanglement negativity, a measure of entanglement for mixed
states, to probe the structure of entanglement in the ground state of a
topologically ordered system. Through analytical calculations of the negativity
in the ground state(s) of the toric code model, we explicitly show that the
entanglement of a region $A$ and its complement $B$ is the sum of two types of
contributions. The first type of contributions consists of \textit{boundary
entanglement}, which we see to be insensitive to tracing out the interior of
$A$ and $B$. It therefore entangles only degrees of freedom in $A$ and $B$ that
are close to their common boundary. As it is well-known, each boundary
contribution is proportional to the size of the relevant boundary separating
$A$ and $B$ and it includes an additive, universal correction. The second
contribution appears only when $A$ and $B$ are non-contractible regions (e.g.
on a torus) and it consists of long-range entanglement, which we see to be
destroyed when tracing out a non-contractible region in the interior of $A$ or
$B$. Only the long-range contribution to the entanglement may depend on the
specific ground state under consideration.


title:
Effective Cluster Typical Medium Theory for Diagonal Anderson Disorder
  Model in One- and Two-Dimensions

abstract:
  We develop a cluster typical medium theory to study localization in
disordered electronic systems. Our formalism is able to incorporate non-local
correlations beyond the local typical medium theory in a systematic way. The
cluster typical medium theory utilizes the momentum resolved typical density of
states and hybridization function to characterize the localization transition.
We apply the formalism to the Anderson model of localization in one- and
two-dimensions. In one dimension, we find that the critical disorder strength
scales inversely with the linear cluster size with a power-law, $W_c \sim
(1/L_c)^{1/\nu}$; whereas in two dimensions, the critical disorder strength
decreases logarithmically with the linear cluster size. Our results are
consistent with previous numerical work and in agreement with the one-parameter
scaling theory.


title: Describing diffusion, reaction and convection on porous medium

abstract:
  In this paper we present a mathematical model for the electrochemical
deposition aimed at the production of inverse opals. The real system consists
of an arrangement of sub micrometer spheres, through which the species in an
electrolytic medium diffuses until they react to the electrode surface and
become part thereof. Our model consists in formulating convenient boundary
conditions for the transport equation, that somewhat resembles the real system
but is nevertheless simple enough to be solved, and then solve it. Similar
approach was taken by Nicholson [1, 2], except that, to avoid the difficulties
regarding the boundary conditions, he considered none whatsoever, and proposed
a modified diffusion coefficient for the porous medium instead. Apropos, our
model, with moving boundary condition pertain to the class of problems know as
The Stefan problem [3].


title: On column density thresholds and the star formation rate

abstract:
  We present the results of a numerical study designed to address the question
of whether there is a column density threshold for star formation within
molecular clouds. We have simulated a large number of different clouds, with
volume and column densities spanning a wide range of different values, using a
state-of-the-art model for the coupled chemical, thermal and dynamical
evolution of the gas. We show that star formation is only possible in regions
where the mean (area-averaged) column density exceeds $10^{21} \: {\rm
cm^{-2}}$. Within the clouds, we also show that there is a good correlation
between the mass of gas above a K-band extinction $A_{\rm K} = 0.8$ and the
star formation rate (SFR), in agreement with recent observational work.
Previously, this relationship has been explained in terms of a correlation
between the SFR and the mass in dense gas. However, we find that this
correlation is weaker and more time-dependent than that between the SFR and the
column density. In support of previous studies, we argue that dust shielding is
the key process: the true correlation is one between the SFR and the mass in
cold, well-shielded gas, and the latter correlates better with the column
density than the volume density.


title:
TaSer (TabAnno and SeqMiner): a toolset for annotating and querying
  next-generation sequence data

abstract:
  Summary: We develop TaSer (TabAnno and SeqMiner), a toolkit for annotating
and querying next generation sequence (NGS) dataset in tab-delimited files.
TabAnno is a powerful and efficient command-line tool designed to pre-process
sequence data, annotate variations and generate an indexed feature-enriched
project file that can integrate multiple sources of information. Using the
project file generated by TabAnno, complex queries to the sequence dataset can
be performed using SeqMiner, an R-package designed to efficiently access large
datasets. Extracted information can be conveniently viewed and analyzed by
tools in R. TaSer is optimized and computationally more efficient than software
using database systems. It enables annotating and querying NGS dataset using
moderate computing resource. Availability and implementation: TabAnno can be
downloaded from github (zhanxw.github.io/anno/). SeqMiner is distributed on
CRAN (cran.r-project.org/web/packages/seqminer). Contact: X.Z.
(zhanxw@umich.edu) D.J.L (dajiang@umich.edu)


title: On the global existence solution for a chemotaxis model

abstract:
  This paper has been withdrawn by the authors. We consider the
attraction-repulsion chemotaxis system (3 complicated PDEs system) under
homogeneous Neumann boundary conditions in a bounded domain {\Omega} with
smooth boundary, then the classical solutions to the system are
uniformly-in-time bounded. After the local existence and uniqueness of
solutions was proved, some priory estimates and proves will be established for
the global existence of solutions (see the complete abstract in the PDF version
of paper).


title:
Density profiles and collective modes of a Bose-Einstein condensate with
  light-induced spin-orbit coupling

abstract:
  The phases of a Bose-Einstein condensate (BEC) with light-induced spin-orbit
coupling (SOC) are studied within the mean-field approximation. The mixed BEC
phase, in which the system condenses in a superposition of two plane wave
states, is found to be stable for sufficiently small light-atom coupling,
becoming unstable in a continuous fashion with increasing light-atom coupling.
The structure of the phase diagram at fixed chemical potential for bosons with
SOC is shown to imply an unusual density dependence for a trapped mixed BEC
phase, with the density of one dressed spin state increasing with increasing
radius, providing a unique experimental signature of this state. The collective
Bogoliubov sound mode is shown to also provide a signature of the mixed BEC
state, vanishing as the boundary to the regime of phase separation is
approached.


title: Fast Covariance Estimation for High-dimensional Functional Data

abstract:
  For smoothing covariance functions, we propose two fast algorithms that scale
linearly with the number of observations per function. Most available methods
and software cannot smooth covariance matrices of dimension $J \times J$ with
$J>500$; the recently introduced sandwich smoother is an exception, but it is
not adapted to smooth covariance matrices of large dimensions such as $J \ge
10,000$. Covariance matrices of order $J=10,000$, and even $J=100,000$, are
becoming increasingly common, e.g., in 2- and 3-dimensional medical imaging and
high-density wearable sensor data. We introduce two new algorithms that can
handle very large covariance matrices: 1) FACE: a fast implementation of the
sandwich smoother and 2) SVDS: a two-step procedure that first applies singular
value decomposition to the data matrix and then smoothes the eigenvectors.
Compared to existing techniques, these new algorithms are at least an order of
magnitude faster in high dimensions and drastically reduce memory requirements.
The new algorithms provide instantaneous (few seconds) smoothing for matrices
of dimension $J=10,000$ and very fast ($<$ 10 minutes) smoothing for
$J=100,000$. Although SVDS is simpler than FACE, we provide ready to use,
scalable R software for FACE. When incorporated into R package {\it refund},
FACE improves the speed of penalized functional regression by an order of
magnitude, even for data of normal size ($J <500$). We recommend that FACE be
used in practice for the analysis of noisy and high-dimensional functional
data.


title:
Multi-particle correlations, many particle systems, and entropy in
  effective field theories

abstract:
  We discuss the treatment, in an effective field theory, of multi-particle
correlations within a "large" system. We show that the act of coarse-graining
necessarily introduces violations of unitarity in the evolution of states where
the particle number is not defined. For an interacting system, such unitarity
violations can cascade from the ultraviolet scale to the infrared in a "short"
time. Hence, an effective field theory will be grossly inadequate for
describing multi-particle correlations and related observables, even far away
from the cut-off scale $\Lambda$. We furthermore argue that if the system is
strongly coupled at $\Lambda$, than its final state {\em in the Effective Field
Theory} (EFT) will appear as the highest entropy state if only low cumulants
and correlations of the EFT degrees of freedom are measured.
  Heuristically, this can serve as an explanation of how "entropy" is created
in a microscopically unitary evolution of a Quantum Field Theory (QFT). We
conclude by discussing how these considerations might provide a clue to the
apparent thermalization in a hadronic collision even in comparatively small
systems, as well as the so-called black hole information paradox; We argue the
"paradoxes" are likely to be artifacts of using an effective theory beyond its
domain of validity.


title: On the Resilience of Bipartite Networks

abstract:
  Motivated by problems modeling the spread of infections in networks, in this
paper we explore which bipartite graphs are most resilient to widespread
infections under various parameter settings. Namely, we study bipartite
networks with a requirement of a minimum degree $d$ on one side under an
independent infection, independent transmission model. We completely
characterize the optimal graphs in the case $d=1$, which already produces
non-trivial behavior, and we give extremal results for the more general cases.
We show that in the case $d=2$, surprisingly, the optimally resilient set of
graphs includes a graph that is not one of the two "extremes" found in the case
$d=1$.
  Then, we briefly examine the case where we force a connectivity requirement
instead of a one-sided degree requirement and again, we find that the set of
the most resilient graphs contains more than the two "extremes." We also show
that determining the subgraph of an arbitrary bipartite graph most resilient to
infection is NP-hard for any one-sided minimal degree $d \ge 1$.


title: On nonlinear interpolation

abstract:
  In a case study on asymptotics of spectral quantities of Schr\"odinger
operators we show how the Riesz-Thorin theorem on the interpolation of linear
operators can be extended to nonlinear maps.


title: Local linear dependence seen through duality II

abstract:
  A vector space S of linear operators between finite-dimensional vector spaces
U and V is called locally linearly dependent (in abbreviate form: LLD) when
every vector x in U is annihilated by a non-zero operator in S. By a duality
argument, one sees that studying LLD operator spaces amounts to studying vector
spaces of matrices with rank less than the number of columns, or,
alternatively, vector spaces of non-injective operators.
  In this article, this insight is used to obtain classification results for
LLD spaces of small dimension or large essential range (the essential range
being the sum of all the ranges of the operators in S). We show that such
classification theorems can be obtained by translating into the context of LLD
spaces Atkinson's classification of primitive spaces of bounded rank matrices;
we also obtain a new classification theorem for such spaces that covers a range
of dimensions for the essential range that is roughly twice as large as that in
Atkinson's theorem. In particular, we obtain a classification of all
4-dimensional LLD operator spaces for fields with more than 3 elements
(beforehand, such a classification was known only for algebraically closed
fields and in the context of primitive spaces of matrices of bounded rank).
  These results are applied to obtain improved upper bounds for the maximal
rank in a minimal LLD operator space.


title:
TASC-1D-cSi: a simulation tool to scrutinize the thermal impacts on the
  performances of crystalline silicon solar cells

abstract:
  The capabilities of a simulation tool for the in-depth analysis of the
thermal impacts on the performances of solar cells are described. TASC-1D
(Thermal Analysis of Solar Cells - 1D, version cSi) solves the coupled
electrical, radiative and thermal transport problems for a crystalline silicon
cell, as a function of irradiation and thermal conditions. In addition to the
electrical outputs that are obtained with the existing simulation tools, it
provides the cell equilibrium temperature as well as the spatial and spectral
distributions of many relevant quantities. The physical modeling and associated
numerical solution techniques are summarized. Result cases with a prescribed
cell temperature demonstrate that the code performs well, is able to provide
valuable information on the quantum efficiency and power loss mechanisms, and
is capable of handling diffuse irradiations. The intricate correlation between
thermal sources and optical-electrical losses is discussed. The other cases
include the solution of the heat transfer problem and analyses are conducted on
the cell operating temperature and efficiency as a function of the thermal
conditions. This simulation tool is likely to allow new optimizations of
photovoltaic cells that include a thermal criterion in addition to the optical
and electrical criteria.


title: Cyclic amalgams, HNN extensions, and Garside one-relator groups

abstract:
  Garside groups are a natural lattice-theoretic generalisation of the braid
groups and spherical type Artin--Tits groups. Here we show that the class of
Garside groups is closed under some free products with cyclic amalgamated
subgroups. We deduce that every tree product of infinite cyclic groups is a
Garside group. Moreover, we study those cyclic HNN extensions of Garside groups
that are Garside groups as well. Using a theorem of Pietrowski, we conclude
this paper by stating that a non-cyclic one-relator group is Garside if and
only if its centre is nontrivial.


title:
Dark Matter and Pulsar Model Constraints from Galactic Center Fermi-LAT
  Gamma Ray Observations

abstract:
  Employing Fermi-LAT gamma ray observations, several independent groups have
found excess extended gamma ray emission at the Galactic center (GC). Both,
annihilating dark matter (DM) or a population of $\sim 10^3$ unresolved
millisecond pulsars (MSPs) are regarded as well motivated possible
explanations. However, there is significant uncertainties in the diffuse
galactic background at the GC. We have performed a revaluation of these two
models for the extended gamma ray source at the GC by accounting for the
systematic uncertainties of the Galactic diffuse emission model. We also
marginalize over point source and diffuse background parameters in the region
of interest. We show that the excess emission is significantly more extended
than a point source. We find that the DM (or pulsars population) signal is
larger than the systematic errors and therefore proceed to determine the
sectors of parameter space that provide an acceptable fit to the data. We found
that a population of order a 1000 MSPs with parameters consistent with the
average spectral shape of Fermi-LAT measured MSPs was able to fit the GC excess
emission. For DM, we found that a pure $\tau^+\tau^-$ annihilation channel is
not a good fit to the data. But a mixture of $\tau^+\tau^-$ and $b\bar{b}$ with
a $\left<\sigma v\right>$ of order the thermal relic value and a DM mass of
around 20 to 60 GeV provides an adequate fit.

categories: astro-ph.HE astro-ph.CO astro-ph.GA hep-ph


title: A Scalable Approximate Model Counter

abstract:
  Propositional model counting} (#SAT), i.e., counting the number of satisfying
assignments of a propositional formula, is a problem of significant theoretical
and practical interest. Due to the inherent complexity of the problem,
approximate model counting, which counts the number of satisfying assignments
to within given tolerance and confidence level, was proposed as a practical
alternative to exact model counting. Yet, approximate model counting has been
studied essentially only theoretically. The only reported implementation of
approximate model counting, due to Karp and Luby, worked only for DNF formulas.
A few existing tools for CNF formulas are bounding model counters; they can
handle realistic problem sizes, but fall short of providing counts within given
tolerance and confidence, and, thus, are not approximate model counters.
  We present here a novel algorithm, as well as a reference implementation,
that is the first scalable approximate model counter for CNF formulas. The
algorithm works by issuing a polynomial number of calls to a SAT solver. Our
tool, ApproxMC, scales to formulas with tens of thousands of variables. Careful
experimental comparisons show that ApproxMC reports, with high confidence,
bounds that are close to the exact count, and also succeeds in reporting bounds
with small tolerance and high confidence in cases that are too large for
computing exact model counts.


title: A note on the positivity of a quasi-local mass in general dimensions

abstract:
  Wang and Yau [10] introduced a quasi-local mass, which is a hyperbolic
background generalization of Liu-Yau's expression [7] [8], and proved its
positivity. In this note, we prove that the positivity of this quasi-local mass
is still valid under weaker assumptions on the boundary hypersurface in general
dimensions. The method we used is similar to that used by Eichmair, Miao and
Wang in [4].


title: Edge Universality of Beta Ensembles

abstract:
  We prove the edge universality of the beta ensembles for any $\beta\ge 1$,
provided that the limiting spectrum is supported on a single interval, and the
external potential is $\mathscr{C}^4$ and regular. We also prove that the edge
universality holds for generalized Wigner matrices for all symmetry classes.
Moreover, our results allow us to extend bulk universality for beta ensembles
from analytic potentials to potentials in class $\mathscr{C}^4$.


title:
Computation of sparse low degree interpolating polynomials and their
  application to derivative-free optimization

abstract:
  Interpolation-based trust-region methods are an important class of algorithms
for Derivative-Free Optimization which rely on locally approximating an
objective function by quadratic polynomial interpolation models, frequently
built from less points than there are basis components. Often, in practical
applications, the contribution of the problem variables to the objective
function is such that many pairwise correlations between variables are
negligible, implying, in the smooth case, a sparse structure in the Hessian
matrix. To be able to exploit Hessian sparsity, existing optimization
approaches require the knowledge of the sparsity structure. The goal of this
paper is to develop and analyze a method where the sparse models are
constructed automatically. The sparse recovery theory developed recently in the
field of compressed sensing characterizes conditions under which a sparse
vector can be accurately recovered from few random measurements. Such a
recovery is achieved by minimizing the l1-norm of a vector subject to the
measurements constraints. We suggest an approach for building sparse quadratic
polynomial interpolation models by minimizing the l1-norm of the entries of the
model Hessian subject to the interpolation conditions. We show that this
procedure recovers accurate models when the function Hessian is sparse, using
relatively few randomly selected sample points. Motivated by this result, we
developed a practical interpolation-based trust-region method using
deterministic sample sets and minimum l1-norm quadratic models. Our
computational results show that the new approach exhibits a promising numerical
performance both in the general case and in the sparse one.


title: How close is Earth to a runaway greenhouse?

abstract: This paper has been withdrawn by the author in favor of a private review.


title: Fermionic shock waves - dissipative or dispersive?

abstract:
  The collision of two clouds of Fermi gas at unitarity (UFG) has been recently
observed to lead to shock waves whose regularization mechanism, dissipative or
dispersive, is being debated. While classical, dissipative shocks, as in gas
dynamics, develop a steep, localized shock front that translates at a
well-defined speed, dispersively regularized shocks are distinguished by an
expanding region of short wavelength oscillations with two speeds, those of the
leading and trailing edges. For typical UFG experimental conditions, the
theoretical oscillation length scale is smaller than the resolution of present
imaging systems so it is unclear how to determine the shock type from its
structure alone. Two experimental methods to determine the appropriate
regularization mechanism are proposed: measurement of the shock speed and
observation of a one-dimensional collision experiment with sufficiently tight
radial confinement.


title: The Homomorphism Poset of $K_{3,3}$

abstract:
  A geometric graph \G is a simple graph drawn in the plane, on points in
general position, with straight-line edges. We call \G a geometric realization
of the underlying abstract graph G. A geometric homomorphism from \G to \H is a
vertex map that preserves adjacencies and crossings (but not necessarily
non-adjacencies or non-crossings). Geometric homomorphisms can be used to
define a partial order on the set of isomorphism classes of geometric
realizations of an abstract graph G. In this paper, the homomorphism poset of
K_{3,3} is determined.


title: Non-equilibrium dynamics in the antiferromagnetic Hubbard model

abstract:
  We investigate by means of the time-dependent Gutzwiller approximation the
out-of-equilibrium dynamics of an antiferromagnetic state evolved with the
Hubbard model Hamiltonian after a sudden change of the repulsion strength $U$.
We find that magnetic order survives more than what expected on the basis of
thermalization arguments, in agreement with recent DMFT calculations. In
addition, we find evidence of a dynamical transition for quenches to large
values of $U$ between a coherent antiferromagnet characterized by a finite
quasiparticle residue to an incoherent one with vanishing residue, that finally
turns into a paramagnet for even larger $U$.


title: Anomalous radiative trapping in laser fields of extreme intensity

abstract:
  We demonstrate that charged particles in a sufficiently intense standing wave
are compressed toward, and oscillate synchronously at, the maxima of the
electric field. This unusual trapping behaviour, which we call 'anomalous
radiative trapping' (ART), opens up new possibilities for the generation of
radiation and particle beams, both of which are high-energy, directed and
collimated. ART also provides a mechanism for particle control in
high-intensity QED experiments.


title:
Constraints on the Galactic Population of TEV Pulsar Wind Nebulae Using
  Fermi Large Area Telescope Observations

abstract:
  Pulsar wind nebulae (PWNe) have been established as the most populous class
of TeV gamma-ray emitters. Since launch, the Fermi Large Area Telescope
(LAT)identified five high-energy (100MeV <E< 100 GeV) gamma-ray sources as
PWNe, and detected a large number of PWNe candidates, all powered by young and
energetic pulsars. The wealth of multi-wavelength data available and the new
results provided by Fermi-LAT give us an opportunity to find new PWNe and to
explore the radiative processes taking place in known ones. The TeV gamma-ray
unidentifiedsources (UNIDs) are the best candidates for finding new PWNe. Using
45 months of Fermi-LAT data for energies above 10 GeV, an analysis was
performed near the position of 58TeV PWNe and UNIDs within 5deg of the Galactic
Plane to establish new constraints on PWNe properties and find new clues on the
nature of UNIDs. Of the 58 sources, 30 were detected, and this work provides
their gamma-rayfluxes for energies above 10 GeV. The spectral energy
distributions (SED) andupper limits, in the multi-wavelength context, also
provide new information on the source nature and can help distinguish between
emission scenarios, i.e. between classification as a pulsar candidate or as a
PWN candidate. Six new GeV PWNe candidates are described in detail and compared
with existing models. A population study of GeV PWNe candidates as a function
of the pulsar/PWN system characteristics is presented.


title: CMB dipole asymmetry from a fast roll phase

abstract:
  The observed CMB (cosmic microwave background) dipole asymmetry cannot be
explained by a single field model of inflation - it inevitably requires more
than one field where one of the fields is responsible for amplifying the
super-Hubble fluctuations beyond the pivot scale. Furthermore the current
constraints on $f_NL$ and $tau_NL$ require that such an amplification cannot
produce large non-Gaussianity. In this paper we propose a model to explain this
dipole asymmetry from a spectator field, which is responsible for generating
all the curvature perturbations, but has a temporary fast roll phase before the
Hubble exit of the pivot scale. The current data prefers spectator scenario
because it leaves no isocurvature perturbations. The spectator model will also
satisfy the well-known constraints arising from quasars, and the quadrupole and
octupole of the CMB.


title:
Study of the possibility of eliminating the Gibbs paradox within the
  framework of classical thermodynamics

abstract:
  The formulas for the entropy of ideal gases mixture and the entropy change in
mixing of ideal gases on the basis of the third law of thermodynamics were
obtained. It is shown that when using these formulas, the Gibbs paradox within
the framework of classical thermodynamics does not arise.


title: Single-Molecule Observation of Long Jumps in Polymer Adsorption

abstract:
  Single-molecule fluorescence imaging of adsorption onto initially-bare
surfaces shows that polymer chains need not localize immediately after arrival.
In a system optimized to present limited adsorption sites (quartz surface to
which polyethylene glycol (PEG) is exposed in aqueous solution at pH = 8.2) we
find that some chains diffuse back into bulk solution and re-adsorb at some
distance away, sometimes multiple times before either they localize at a stable
position or else diffuse away into bulk solution. This mechanism of surface
diffusion is considerably more rapid than the classical model in which adsorbed
polymers crawl on surfaces while the entire molecule remains adsorbed. The
trajectories with jumps follow a truncated Levy distribution of step size with
limiting slope -2.5, consistent with a well-defined, rapid surface diffusion
coefficient over the times we observe.


title:
New Class of Magnetized Inhomogeneous Bianchi Type-I Cosmological Model
  with Variable Magnetic Permeability in Lyra Geometry

abstract:
  Inhomogeneous Bianchi type-I cosmological model with electro-magnetic field
based on Lyra geometry is investigated. Using separated method, the Einstein
field equations have been solved analytically with the aid of Mathematica
programm. A new class of exact solutions have been obtained by considering the
potentials of metric and displacement field are functions of coordinates t and
x. We have assumed that F(12) is the only non-vanishing component of
electro-magnetic field tensor F(ij). The Maxwells equations show that F(12) is
the function of x alone whereas the magnetic permeability is the function of x
and t both. To get the deterministic solution, it has been assumed that the
expansion scaler Theta in the model is proportional to the value sigma(11) of
the shear tensor sigma(ij). Some physical and geometric properties of the model
are also discussed and graphed.


title: Recent results on hadron physics at KLOE

abstract:
  One of the basic motivations of the KLOE and KLOE-2 collaborations is the
test of fundamental symmetries and the search for phenomena beyond the Standard
Model via the hadronic and leptonic decays of ground-state mesons and via their
production in the fusion of virtual gamma quanta exchanged between colliding
electrons and positrons. This contribution includes brief description of
results of recent analysis of the KLOE data aimed at (i) the search for the
dark matter boson, (ii) determination of the hadronic and light-by-light
contributions to the g-2 muon anomaly and (iii) tests of QCD anomalies.