title: Unidentified Moving Objects in Next Generation Time Domain Surveys

abstract:
  Existing and future wide-field photometric surveys will produce a time-lapse
movie of the sky that will revolutionize our census of variable and moving
astronomical and atmospheric phenomena. As with any revolution in scientific
measurement capability, this new species of data will also present us with
results that are sure to surprise and confound our understanding of the cosmos.
While we cannot predict the unknown yields of such endeavors, it is a
beneficial exercise to explore certain parameter spaces using reasonable
assumptions for rates and observability. To this end I present a simple
parameterized model of the detectability of unidentified flying objects (UFOs)
with the Large Synoptic Survey Telescope (LSST). I also demonstrate that the
LSST is well suited to place the first systematic constraints on the rate of
UFO and extraterrestrial visits to our world.


title:
A multi-opinion evolving voter model with infinitely many phase
  transitions

abstract:
  We consider an idealized model in which individuals' changing opinions and
their social network coevolve, with disagreements between neighbors in the
network resolved either through one imitating the opinion of the other or by
reassignment of the discordant edge. Specifically, an interaction between $x$
and one of its neighbors $y$ leads to $x$ imitating $y$ with probability
$(1-\alpha)$ and otherwise (i.e., with probability $\alpha$) $x$ cutting its
tie to $y$ in order to instead connect to a randomly chosen individual.
Building on previous work about the two-opinion case, we study the
multiple-opinion situation, finding that the model has infinitely many phase
transitions. Moreover, the formulas describing the end states of these
processes are remarkably simple when expressed as a function of $\beta =
\alpha/(1-\alpha)$.

categories: physics.soc-ph cond-mat.dis-nn cs.SI math.PR nlin.AO


title: On the security of key distribution based on Johnson-Nyquist noise

abstract:
  We point out that arguments for the security of Kish's noise-based
cryptographic protocol have relied on an unphysical no-wave limit, which if
taken seriously would prevent any correlation from developing between the
users. We introduce a noiseless version of the protocol, also having illusory
security in the no-wave limit, to show that noise and thermodynamics play no
essential role. Then we prove generally that classical electromagnetic
protocols cannot establish a secret key between two parties separated by a
spacetime region perfectly monitored by an eavesdropper. We note that the
original protocol of Kish is vulnerable to passive time-correlation attacks
even in the quasi-static limit. Finally we show that protocols of this type can
be secure in practice against an eavesdropper with noisy monitoring equipment.
In this case the security is a straightforward consequence of Maurer and Wolf's
discovery that key can be distilled by public discussion from correlated random
variables in a wide range of situations where the eavesdropper's noise is at
least partly independent from the users' noise.


title:
The Influence of Radial Stellar Migration on the Chemical Evolution of
  the Milky Way

abstract:
  Stellar migration is an important dynamical process in Galactic disk. Here we
model the radial stellar migration in the Galactic disk with an analytical
method, then add it to detailed Galactic chemical evolution model to study the
influence of radial stellar migration on the chemical evolution of the Milky
Way, especially for the abundance gradients. We found that the radial stellar
migration in the Galactic disk can make the profile of the G-dwarf metallicity
distribution of the solar neighborhood taller and narrower, thus it becomes
another solution to the "G-dwarf problem". It can also scatter the
age-metallicity relation. However, after the migration, the abundance
distributions along the Galactic radius don't change much, namely the abundance
gradients would not be flattened by the radial stellar migration, which is
different from the predictions of many theoretical works. But it can flatten
the radial gradients of the mean chemical abundance of stars, and older stars
possess flatter abundance gradients than younger stars. The most significant
effect of the radial stellar migration on the chemical abundance is that at a
position it scatters the abundance of stars there from a relatively
concentrated value to a range.


title: Noisy Laplace deconvolution with error in the operator

abstract:
  We adress the problem of Laplace deconvolution with random noise in a
regression framework. The time set is not considered to be fixed, but grows
with the number of observation points. Moreover, the convolution kernel is
unknown, and accessible only through experimental noise. We make use of a
recent procedure of estimation which couples a Galerkin projection of the
operator on Laguerre functions, with a threshold performed both on the operator
and the observed signal. We establish the minimax optimality of our procedure
under the squared loss error, when the smoothness of the signal is measured in
a Laguerre-Sobolev sense and the kernel satisfies fair blurring assumptions. It
is important to stress that the resulting process is adaptive with regard both
to the target function's smoothness and to the kernel's blurring properties. We
end this paper with a numerical study emphazising the good practical
performances of the procedure on concrete examples.


title: Correct light deflection in Weyl conformal gravity

abstract:
  The conformal gravity fit to observed galactic rotation curves requires
{\gamma}>0. On the other hand, conventional method for light deflection by
galaxies gives a negative contribution to Schwarzschild value for {\gamma}>0,
which is contrary to observation. Thus, it is very important that the
contribution to bending should in principle be positive, no matter how small
its magnitude is. Here we show that the Rindler-Ishak method gives a positive
contribution to Schwarzschild deflection for {\gamma}>0, as desired. We also
obtain the exact local coupling term derived earlier by Sereno. These results
indicate that conformal gravity can potentially test well against all
astrophysical observations to date.


title:
Properties of Random Complex Chemical Reaction Networks and Their
  Relevance to Biological Toy Models

abstract:
  We investigate the properties of large random conservative chemical reaction
networks composed of elementary reactions endowed with either mass-action or
saturating kinetics, assigning kinetic parameters in a
thermodynamically-consistent manner. We find that such complex networks exhibit
qualitatively similar behavior when fed with external nutrient flux. The
nutrient is preferentially transformed into one specific chemical that is an
intrinsic property of the network. We propose a self-consistent proto-cell toy
model in which the preferentially synthesized chemical is a precursor for the
cell membrane, and show that such proto-cells can exhibit sustainable
homeostatic growth when fed with any nutrient diffusing through the membrane,
provided that nutrient is metabolized at a sufficient rate.


title:
Water dynamics: Relation between hydrogen bond bifurcations, molecular
  jumps, local density & hydrophobicity

abstract:
  Structure and dynamics of water remain a challenge. Resolving the properties
of hydrogen bonding lies at the heart of this puzzle. Here we employ ab initio
Molecular Dynamics (AIMD) simulations over a wide temperature range. The total
simulation time was approx 2 ns. Both bulk water and water in the presence of a
small hydrophobic molecule were simulated. We show that large-angle jumps and
bond bifurcations are fundamental properties of water dynamics and that they
are intimately coupled to both local density and hydrogen bond stretch
oscillations in scales from about 60 to a few hundred femtoseconds: Local
density differences are the driving force for bond bifurcations and the
consequent large-angle jumps. The jumps are intimately connected to the
recently predicted energy asymmetry. Our analysis also appears to confirm the
existence of the so-called negativity track provided by the lone pairs of
electrons on the oxygen atom to enable water rotation.


title:
Out-of-equilibrium properties and non-linear effects for interacting
  quantum impurity systems in their strong coupling regime

abstract:
  We provide an exact description of out-of-equilibrium fixed points in quantum
impurity systems, that is able to treat time-dependent forcing. Building on
this, we then show that analytical out-of-equilibrium results, that exactly
treat interactions, can be obtained in interacting quantum impurity systems in
their strong coupling regime, provided they are integrable \emph{at}
equilibrium and they are "super Fermi liquids", i.e. they only allow for
integer charge hopping. For such systems we build an out-of-equilibrium strong
coupling expansion, akin to a Sommerfeld expansion in interacting systems. We
apply our approach to the Interacting Resonant Level model, and obtain the
exact expansion around the low energy fixed point of the universal scaling
function for the charge current as a function of voltage, temperature, and
frequency, up to order seven.


title:
A note on stochastic Schr\"odinger equations with fractional
  multiplicative noise

abstract:
  This work is devoted to non-linear stochastic Schr\"odinger equations with
multiplicative fractional noise, where the stochastic integral is defined
following the Riemann-Stieljes approach of Z\"ahle. Under the assumptions that
the initial condition is in the Sobolev space $H^q(\Rm^n)$ for a dimension $n$
less than three and $q$ an integer greater or equal to zero, that the noise is
a $Q-$fractional Brownian motion with Hurst index $H\in(1/2,1)$ and spatial
regularity $H^{q+4}(\Rm^n)$, as well as appropriate hypotheses on the
non-linearity, we obtain the local existence of a unique pathwise solution in
$\calC^0(0,T,H^q(\Rm^n)) \cap \calC^{0,\gamma}(0,T,H^{q-2}(\Rm^n))$, for any
$\gamma \in [0,H)$. Contrary to the parabolic case, standard fixed point
techniques based on the mild formulation of the SPDE cannot be directly used
because of the weak smoothing in time properties of the Schr\"odinger
semigroup. We follow here a different route and our proof relies on a change of
phase that removes the noise and leads to a Schr\"odinger equation with a
magnetic potential that is not differentiable in time.


title:
On the Polyak convexity principle and its application to variational
  analysis

abstract:
  According to a result due to B.T. Polyak, a mapping between Hilbert spaces,
which is $C^{1,1}$ around a regular point, carries a ball centered at that
point to a convex set, provided that the radius of the ball is small enough.
The present paper considers the extension of such result to mappings defined on
a certain subclass of uniformly convex Banach spaces. This enables one to
extend to such setting a variational principle for constrained optimization
problems, already observed in finite dimension, that establishes a convex
behaviour for proper localizations of them. Further variational consequences
are explored.


title: Cocalibrated G_2-manifolds with Ricci flat characteristic connection

abstract:
  Any 7-dimensional cocalibrated G_2-manifold admits a unique connection
$\nabla$ with skew symmetric torsion. We study these manifolds under the
additional condition that the $\nabla$-Ricci tensor vanishes. In particular, we
describe their geometry in case of a maximal number of $\nabla$-parallel vector
fields.


title: Agent-based modeling of a price information trading business

abstract:
  We describe an agent-based simulation of a fictional (but feasible)
information trading business. The Gas Price Information Trader (GPIT) buys
information about real-time gas prices in a metropolitan area from drivers and
resells the information to drivers who need to refuel their vehicles.
  Our simulation uses real world geographic data, lifestyle-dependent driving
patterns and vehicle models to create an agent-based model of the drivers. We
use real world statistics of gas price fluctuation to create scenarios of
temporal and spatial distribution of gas prices. The price of the information
is determined on a case-by-case basis through a simple negotiation model. The
trader and the customers are adapting their negotiation strategies based on
their historical profits.
  We are interested in the general properties of the emerging information
market: the amount of realizable profit and its distribution between the trader
and customers, the business strategies necessary to keep the market operational
(such as promotional deals), the price elasticity of demand and the impact of
pricing strategies on the profit.


title: First principles description of the giant dipole resonance in 16O

abstract:
  We present an ab-initio calculation of the giant dipole resonance in 16O
based on a nucleon-nucleon (NN) interaction from chiral effective field theory
that reproduces NN scattering data with high accuracy. By merging the Lorentz
integral transform and the coupled-cluster methods, we extend the previous
theoretical limits for break-up observables in light nuclei with mass numbers
(A<=7), and address the collective giant dipole resonance of 16O. We
successfully benchmark the new approach against virtually exact results from
the hyper-spherical harmonics method in 4He. Our results for 16O reproduce the
position and the total strength (bremsstrahlung sum rule) of the dipole
response very well. When compared to the cross section from photo-absorption
experiments the theoretical curve exhibits a smeared form of the peak. The tail
region between 40 and 100 MeV is reproduced within uncertainties.


title: Emergence of Majorana modes in cylindrical nanowires

abstract:
  We present calculations of Majorana edge modes in cylindrical nanowires of a
semiconductor material with proximity-induced superconductivity. We consider a
Rashba field along the transverse direction and an applied magnetic field in
arbitrary orientation. Our analysis is based on exact numerical
diagonalizations for the finite cylinder and on the complex band structure for
the semi-infinite one. Orbital effects are responsible for a strong anisotropy
of the critical field for which the effective gap vanishes. Robust Majorana
modes are induced by the parallel field component and we find regimes with more
than one Majorana mode on the same edge. Experimentally, they would manifest as
a specific sequence of zero-bias conductances as a function of magnetic field.
In the finite cylinder, a degradation of the Majorana modes due to interference
of the two edges leads to oscillating non zero energies for large enough
fields.


title: An analytically tractable model of bad metals

abstract:
  We discuss a model Kondo-type Hamiltonian representing an analytically
tractable version of the model used by Yin {\it et.al.}, Phys. Rev. B{\bf 86},
2399 (2012) to explain the non-Fermi liquid behavior of iron chalcogenides and
ruthenates in an intermediate energy range. We consider a regime where a
complete screening of the local degrees of freedom proceeds in two stages
described by two characteristic energy scales $T_K^{orb} >> E_0$. The first
scale marks a screening of the orbital degrees of freedom and the second one
marks a crossover to the regime with coherent propagation of quasiparticles. We
present analytical results for the specific heat and magnetic susceptibility at
$T << T_K^{orb}$.


title: Photon-mediated electron transport in hybrid circuit-QED

abstract:
  We investigate photon-mediated transport processes in a hybrid circuit-QED
structure consisting of two double quantum dots coupled to a common microwave
cavity. Under suitable resonance conditions, electron transport in one double
quantum dot is facilitated by the transport in the other dot via
photon-mediated processes through the cavity. We calculate the average current
in the quantum dots, the mean cavity photon occupation, and the current
cross-correlations with both a full numerical simulation and a recursive
perturbation scheme that allows us to include the influence of the cavity
order-by-order in the couplings between the cavity and the quantum dot systems.
We can then clearly identify the photon-mediated transport processes.


title: Supersymmetric Heavy Higgs Bosons at the LHC

abstract:
  The search for heavy Higgs bosons is an essential step in the exploration of
the Higgs sector and in probing the Supersymmetric parameter space. This paper
discusses the constraints on the M(A) and tan beta parameters derived from the
bounds on the different decay channels of the neutral H and A bosons accessible
at the LHC, in the framework of the phenomenological MSSM. The implications
from the present LHC results and the expected sensitivity of the 14 TeV data
are discussed in terms of the coverage of the [M(A) - tan beta] plane. New
channels becoming important at 13 and 14 TeV for low values of tan beta are
characterised in terms of their kinematics and the reconstruction strategies.
The effect of QCD systematics, SUSY loop effects and decays into pairs of SUSY
particles on these constraints are discussed in details.


title: Tropical convexity over max-min semiring

abstract:
  This is a survey on an analogue of tropical convexity developed over the
max-min semiring, starting with the descriptions of max-min segments,
semispaces, hyperplanes and an account of separation and non-separation results
based on semispaces. There are some new results. In particular, we give new
"colorful" extensions of the max-min Caratheodory theorem. In the end of the
paper, we list some consequences of the topological Radon and Tverberg theorems
(like Helly and Centerpoint theorems), valid over a more general class of max-T
semirings, where multiplication is a triangular norm.


title:
A multi-physics and multi-scale numerical approach to microcracking and
  power-loss in photovoltaic modules

abstract:
  A multi-physics and multi-scale computational approach is proposed in the
present work to study the evolution of microcracking in polycrystalline Silicon
(Si) solar cells composing photovoltaic (PV) modules. Coupling between the
elastic and the electric fields is provided according to an equivalent circuit
model for the PV module where the electrically inactive area is determined from
the analysis of the microcrack pattern. The structural scale of the PV
laminate(the macro-model) is coupled to the scale of the polycrystals (the
micro-model) using a multiscale nonlinear finite element approach where the
macro-scale displacements of the Si cell borders are used as boundary
conditions for the micro-model. Intergranular cracking in the Si cell is
simulated using a nonlinear fracture mechanics cohesive zone model (CZM). A
case-study shows the potentiality of the method, in particular as regards the
analysis of the microcrack orientation and distribution, as well as of the
effect of cracking on the electric characteristics of the PV module.


title:
Atomically Sharp 318nm Gd:AlGaN Ultraviolet Light Emitting Diodes on Si
  with Low Threshold Voltage

abstract:
  Self assembled AlGaN polarization-induced nanowire light emitting diodes
(PINLEDs) with Gd-doped AlN active regions are prepared by plasma-assisted
molecular beam epitaxy on Si substrates. Atomically sharp electroluminescence
(EL) from Gd intra-f-shell electronic transitions at 313 nm and 318 nm are
observed under forward biases above 5V. The intensity of the Gd 4f EL scales
linearly with current density and increases at lower temperature. The low
electric field excitation of Gd 4f EL in PINLEDs is contrasted with high field
excitation in Gd:AlGaN MIS nanowire devices (metal/Gd:AlN/polarization induced
n-AlGaN) where it is concluded that PINLED devices offer over a three fold
enhancement in 4f EL intensity at a given device bias.


title:
Constructive Interference in Linear Precoding Systems: Power Allocation
  and User Selection

abstract:
  The exploitation of interference in a constructive manner has recently been
proposed for the downlink of multiuser, multi-antenna transmitters. This novel
linear precoding technique, herein referred to as constructive interference
zero forcing (CIZF) precoding, has exhibited substantial gains over
conventional approaches; the concept is to cancel, on a symbol-by-symbol basis,
only the interfering users that do not add to the intended signal power. In
this paper, the power allocation problem towards maximizing the performance of
a CIZF system with respect to some metric (throughput or fairness) is
investigated. What is more, it is shown that the performance of the novel
precoding scheme can be further boosted by choosing some of the constructive
multiuser interference terms in the precoder design. Finally, motivated by the
significant effect of user selection on conventional, zero forcing (ZF)
precoding, the problem of user selection for the novel precoding method is
tackled. A new iterative, low complexity algorithm for user selection in CIZF
is developed. Simulation results are provided to display the gains of the
algorithm compared to known user selection approaches.


title: Self-concordance is NP-hard

abstract:
  We give an elementary proof of a somewhat curious result, namely, that
deciding whether a convex function is self-concordant is in general an
intractable problem.


title: Hidden Momentum and Black Hole Kicks

abstract:
  A stationary magnetic dipole immersed in an electric field carries "hidden"
mechanical momentum. However, the fate of this momentum if the fields are
turned off is unclear. We consider a charge-and-dipole hidden momentum
configuration, and turn off the fields by collapsing a null shell onto the
system, forming a black hole. In numerical calculations we find that the black
hole receives a kick corresponding to 0.1% of the initial stored momentum. When
extrapolated to apply to purely gravitational phenomena, this efficiency
suggests a role for the hidden momentum kick mechanism in generating the binary
black hole "superkicks" observed in numerical simulations of Einstein's
equation.


title: Computational Analysis of Modified Blom's Scheme

abstract:
  To achieve security in wireless networks, it is important to be able to
encrypt and authenticate messages sent among sensor nodes. Due to resource
constraints, achieving such key agreement in wireless sensor networks in
nontrivial. Blom's scheme is a symmetric key exchange protocol used in
cryptography. In this paper, we propose a new key pre-distribution scheme by
modifying Blom's scheme which reduces the computational complexity as well as
memory usage.


title: Strong Krull primes and flat modules

abstract:
  There are several theorems describing the intricate relationship between
flatness and associated primes over commutative Noetherian rings. However,
associated primes are known to act badly over non-Noetherian rings, so one
needs a suitable replacement. In this paper, we show that the behavior of
strong Krull primes most closely resembles that of associated primes over a
Noetherian ring. We prove an analogue of a theorem of Epstein and Yao
characterizing flat modules in terms of associated primes by replacing them
with strong Krull primes. Also, we partly generalize a classical equational
theorem regarding flat base change and associated primes in Noetherian rings.
That is, when associated primes are replaced by strong Krull primes, we show
containment in general and equality in many special cases. One application is
of interest over any Noetherian ring of prime characteristic. We also give
numerous examples to show that our results fail if other popular
generalizations of associated primes are used in place of strong Krull primes.


title: State/event based versus purely Action or State based Logics

abstract:
  Although less studied than purely action or state based logics, state/event
based logics are becoming increasingly important. Some systems are best studied
using structures with information on both states and transitions, and it is
these structures over which state/event based logics are defined. The logic
UCTL and its variants are perhaps the most widely studied and implemented of
these logics to date. As yet, however, no-one seems to have defined UCTL*, a
trivial step but a worthwhile one. Here we do just that, but prove in the cases
of both UCTL and UCTL* that these logics are no more expressive than their more
commonplace fragments. Also, acknowledging the importance of modal transition
systems, we define a state/event based logic over a modified modal transition
system as a precursor to further work.


title: Some results related to the conjecture by Belfiore and Sol\'e

abstract:
  In the first part of the paper, we consider the relation between kissing
number and the secrecy gain. We show that on an $n=24m+8k$-dimensional even
unimodular lattice, if the shortest vector length is $\geq 2m$, then as the
number of vectors of length $2m$ decreases, the secrecy gain increases. We will
also prove a similar result on general unimodular lattices. We will also
consider the situations with shorter vectors. Furthermore, assuming the
conjecture by Belfiore and Sol\'e, we will calculate the difference between
inverses of secrecy gains as the number of vectors varies. We will show by an
example that there exist two lattices in the same dimension with the same
shortest vector length and the same kissing number, but different secrecy
gains. Finally, we consider some cases of a question by Elkies by providing an
answer for a special class of lattices assuming the conjecture of Belfiore and
Sol\'e. We will also get a conditional improvement on some Gaulter's results
concerning the conjecture.


title:
Universal Approximation Depth and Errors of Narrow Belief Networks with
  Discrete Units

abstract:
  We generalize recent theoretical work on the minimal number of layers of
narrow deep belief networks that can approximate any probability distribution
on the states of their visible units arbitrarily well. We relax the setting of
binary units (Sutskever and Hinton, 2008; Le Roux and Bengio, 2008, 2010;
Mont\'ufar and Ay, 2011) to units with arbitrary finite state spaces, and the
vanishing approximation error to an arbitrary approximation error tolerance.
For example, we show that a $q$-ary deep belief network with $L\geq
2+\frac{q^{\lceil m-\delta \rceil}-1}{q-1}$ layers of width $n \leq m +
\log_q(m) + 1$ for some $m\in \mathbb{N}$ can approximate any probability
distribution on $\{0,1,\ldots,q-1\}^n$ without exceeding a Kullback-Leibler
divergence of $\delta$. Our analysis covers discrete restricted Boltzmann
machines and na\"ive Bayes models as special cases.


title: Concur: An Algorithm for Merging Concurrent Changes without Conflicts

abstract:
  Suppose you and I are both editing a document. You make and change and I make
a change, concurrently. Now if we want to still be seeing the same document
then I need to apply your change after mine and you mine after yours. But we
can't just apply them willy-nilly. I must amend yours somehow and you mine. If
my change is written D, yours d, and the amended changes D.d and d.D, we get
*D*D.d=*d*d.D as long as applying is written * and we don't care about what
we're applying the changes to. We start by proving this identity for single
changes and finish by proving it for many.


title: Particle scattering in turbulent plasmas with amplified wave modes

abstract:
  High-energy particles stream during coronal mass ejections or flares through
the plasma of the solar wind. This causes instabilities, which lead to wave
growth at specific resonant wave numbers, especially within shock regions.
These amplified wave modes influence the turbulent scattering process
significantly. In this paper, results of particle transport and scattering in
turbulent plasmas with excited wave modes are presented. The method used is a
hybrid simulation code, which treats the heliospheric turbulence by an
incompressible magnetohydrodynamic approach separately from a kinetic particle
description. Furthermore, a semi-analytical model using quasilinear theory
(QLT) is compared to the numerical results. This paper aims at a more
fundamental understanding and interpretation of the pitch-angle scattering
coefficients. Our calculations show a good agreement of particle simulations
and the QLT for broad-band turbulent spectra; for higher turbulence levels and
particle beam driven plasmas, the QLT approximation gets worse. Especially the
resonance gap at $\mu=0$ poses a well-known problem for QLT for steep
turbulence spectra, whereas test-particle computations show no problems for the
particles to scatter across this region. The reason is that the sharp resonant
wave--particle interactions in QLT are an oversimplification of the broader
resonances in test-particle calculations, which result from nonlinear effects
not included in the QLT. We emphasise the importance of these results for both
numerical simulations and analytical particle transport approaches, especially
the validity of the QLT.


title: Efficient quantification of experimental evidence against local realism

abstract:
  Tests of local realism and their applications aim for very high confidence in
their results even in the presence of potentially adversarial effects. For this
purpose, one can measure a quantity that reflects the amount of violation of
local realism and determine a bound on the probability, according to local
realism, of obtaining a violation at least that observed. In general, it is
difficult to obtain sufficiently robust and small bounds. Here we describe an
efficient protocol for computing such bounds from any set of Bell inequalities
for any number of parties, measurement settings, or outcomes. The protocol can
be applied to tests of other properties (such as entanglement or
dimensionality) that are witnessed by linear inequalities.

categories: quant-ph math-ph math.MP physics.data-an


title: Search for B --> K(*) nu nubar and invisible quarkonium decays

abstract:
  We search for the flavor-changing neutral-current decays B->K(*)nu nubar, and
the invisible decays J/psi->nu nubar and psi(2S)->nu nubar via B->K(*)J/psi and
B->K(*)psi(2S) respectively, using a data sample of 471 x10^6 BB pairs
collected by the BaBar experiment. We fully reconstruct the hadronic decay of
one of the B mesons in the Upsilon(4S)->BB decay, and search for the B->K(*)nu
nubar decay in the rest of the event. We observe no significant excess of
signal decays over background and report branching fraction upper limits of
BR(B+->K+nu nubar)<3.7 x10^-5, BR(B0->K0nu nubar)< 8.1 x10^-5, BR(B+->K*+nu
nubar)<11.6 x10^-5, BR(B0->K*0nu nubar)<9.3 x10^-5, and combined upper limits
of BR(B->Knu nubar)<3.2 x10^-5 and BR(B->K*nu nubar)<7.9 x10^-5, all at the 90%
confidence level. For the invisible quarkonium decays, we report branching
fraction upper limits of BR(J/psi->nu nubar)<3.9 x10^-3 and BR(psi(2S)->nu
nubar)<15.5 x10^-3 at the 90% confidence level. Using the improved kinematic
resolution achieved from hadronic reconstruction, we also provide partial
branching fraction limits for the B->K(*)nu nubar decays over the full
kinematic spectrum.


title:
Use Impulse Response Sequences in the Construction of Number Sequence
  Identities

abstract:
  We define impulse response sequence in the set of all linear recurring
sequences satisfying a linear recurrence relation of order $r$. The generating
function and expression of the impulse response sequence are presented. Some
identities of impulse response sequences including a type of nonlinear
expressions are established. The interrelationship between the impulse response
sequence and other linear recurring sequences in the same set is given, which
is used to transfer the identities of impulse response sequences to those of
the linear recurring sequences in the same set. Some applications of impulse
response sequences to the structure of Stirling numbers of the second order,
the Wythoff array, and the Boustrophedon transform are studied.


title:
Optimizing Throughput on Guaranteed-Bandwidth WAN Networks for the Large
  Synoptic Survey Telescope (LSST)

abstract:
  The Large Synoptic Survey Telescope (LSST) is a proposed 8.4-meter telescope
that will be located in the Andes mountains in Chile. Every 17 seconds, a 6.4
GB image is transferred to Illinois for immediate processing. That transfer
needs to complete within approximately five seconds. LSST is provisioning an
international WAN with a 10Gbps bandwidth guarantee for this and other
project-related data transfers. The stringent latency requirement drives a
re-examination of TCP congestion control for this use case. Specifically, prior
work on dedicated Long Fat Networks (LFNs) does not go far enough in fully
leveraging the opportunity provided by the bandwidth guarantee. This paper
presents an approach for how optimal network throughput can be obtained for the
LSST use case, and the conditions under which any project can achieve data
throughput rates on long-distance networks approaching wire speed.


title:
Unconventional superconducting phases on a two-dimensional extended
  Hubbard model

abstract:
  We study the phase diagram of the extended Hubbard model on a two-dimensional
square lattice, including on-site (U) and nearest-neighbor (V) interactions, at
weak couplings. We show that the charge-density-wave phase that is known to
occur at half-filling when 4V > U gives way to a d_{xy} -wave superconducting
instability away from half-filling, when the Fermi surface is not perfectly
nested, and for sufficiently large repulsive and a range of on-site repulsive
interaction. In addition, when nesting is further suppressed and in presence of
a nearest-neighbor attraction, a triplet time-reversal breaking (p_x +
ip_y)-wave pairing instability emerges, competing with the d_{x2+y2} pairing
state that is known to dominate at fillings just slightly away from half. At
even smaller fillings, where the Fermi surface no longer presents any nesting,
the (p_x +ip_y)-wave superconducting phase dominates in the whole regime of
on-site repulsions and nearest-neighbor attractions, while d_{xy}-pairing
occurs in the presence of on-site attraction. Our results suggest that
zero-energy Majorana fermions can be realized on a square lattice in the
presence of a magnetic field. For a system of cold fermionic atoms on a
two-dimensional square optical lattice, both an on-site repulsion and a
nearest-neighbor attraction would be required, in addition to rotation of the
system to create vortices. We discuss possible ways of experimentally
engineering the required interaction terms in a cold atom system.


title:
Beating the standard quantum limit for force sensing with a coupled
  two-mode optomechanical system

abstract:
  Optomechanics allows the transduction of weak forces to optical fields, with
many efforts approaching the standard quantum limit. We consider force-sensing
using a mirror-in-the-middle setup and use two coupled cavity modes originated
from normal mode splitting for separating pump and probe fields. We find that
this two-mode model can be reduced to an effective single-mode model, if we
drive the pump mode strongly and detect the signal from the weak probe mode.
The optimal force detection sensitivity at zero frequency (DC) is calculated
and we show that one can beat the standard quantum limit by driving the cavity
close to instability. The best sensitivity achievable is limited by mechanical
thermal noise and by optical losses. We also find that the bandwidth where
optimal sensitivity is maintained is proportional to the cavity damping in the
resolved sideband regime. Finally, the squeezing spectrum of the output signal
is calculated, and it shows almost perfect squeezing at DC is possible by using
a high quality factor and low thermal phonon-number mechanical oscillator.


title:
Formation of double ring patterns on Co2MnSi Heusler alloy thin film by
  anodic oxidation under scanning probe microscope

abstract:
  Double ring formation on Co2MnSi (CMS) films is observed at electrical
breakdown voltage during local anodic oxidation (LAO) using atomic force
microscope (AFM). Corona effect and segregation of cobalt in the vicinity of
the rings is studied using magnetic force microscopy and energy dispersive
spectroscopy. Double ring forma-tion is attributed to the interaction of
ablated material with the induced magnetic field during LAO. Steepness of
forward bias transport characteristics from the unperturbed region of the CMS
film suggest a non equilibrium spin contribution. Such mesoscopic textures in
magnetic films by AFM tip can be potentially used for memory storage
applications.


title:
Upper bounds for the number of resonances on geometrically finite
  hyperbolic manifolds

abstract:
  On geometrically finite hyperbolic manifolds $\Gamma\backslash H^{d}$,
including those with non-maximal rank cusps, we give upper bounds on the number
$N(R)$ of resonances of the Laplacian in disks of size $R$ as $R\to \infty$. In
particular, if the parabolic subgroups of $\Gamma$ satisfy a certain
Diophantine condition, the bound is $N(R)= O(R^d (\log R)^{d+1})$.


title:
Higgs Boson Mass, Proton Decay, Naturalness and Constraints of LHC and
  Planck Data

abstract:
  A Higgs boson mass $\sim 126$ GeV as determined by the LHC data requires a
large loop correction which in turn implies a large sfermion mass. Implication
of this result for the stability of the proton in supersymmetric grand unified
theories is examined including other experiments constraints along with the
most recent result on cold dark matter from Planck. It is shown that over the
allowed parameter space of supergravity unified models, proton lifetime is
highly sensitive to the Higgs boson mass and a few GeV shift in its mass can
change the proton decay lifetime for the mode $p\to \bar \nu K^+$ by as much as
two orders of magnitude or more. An analysis is also given on the nature of
radiative breaking of the electroweak symmetry in view of the high Higgs boson,
and it is shown that most of the parameter space of universal and non-universal
supergravity unified models lies on the Hyperbolic Branch of radiative breaking
of the electroweak symmetry, while the Ellipsoidal Branch and the Focal Point
regions are highly depleted and contain only a very small region of the allowed
parameter space. Also discussed are the naturalness criteria when the proton
stability constraints along with the electroweak symmetry breaking are
considered together. It is shown that under the assumed naturalness criteria
the overall fine tuning is improved for larger values of the scalar mass with
the inclusion of the proton stability constraint. Thus the naturalness criteria
including proton stability along with electroweak symmetry breaking constraints
tend to favor the weak scale of SUSY in the several TeV region. Implications
for the discovery of supersymmetry in view of the high Higgs mass are briefly
discussed.


title: On the Scission Point Configuration of Fisioning Nuclei

abstract:
  The scission of a nucleus into two fragments is at present the least
understood part of the fission process, though the most important for the
formation of the observables. To investigate the potential energy landscape at
the largest possible deformations, i.e. at the scission point (line,
hypersurface), the Strutinsky's optimal shape approach is applied.
  For the accurate description of the mass-asymmetric nuclear shape at the
scission point, it turned out necessary to construct an interpolation between
the two sets of constraints for the elongation and mass asymmetry which are
applied successfully at small deformations (quadrupole and octupole moments)
and for separated fragments (the distance between the centers of mass and the
difference of fragments masses). In addition, a constraint on the neck radius
was added, what makes it possible to introduce the so called super-short and
super-long shapes at the scission point and to consider the contributions to
the observable data from different fission modes. The calculated results for
the mass distribution of the fission fragment and the Coulomb repulsion energy
"immediately after scission" are in a reasonable agreement with experimental
data.


title:
Independent Vector Analysis: Identification Conditions and Performance
  Bounds

abstract:
  Recently, an extension of independent component analysis (ICA) from one to
multiple datasets, termed independent vector analysis (IVA), has been the
subject of significant research interest. IVA has also been shown to be a
generalization of Hotelling's canonical correlation analysis. In this paper, we
provide the identification conditions for a general IVA formulation, which
accounts for linear, nonlinear, and sample-to-sample dependencies. The
identification conditions are a generalization of previous results for ICA and
for IVA when samples are independently and identically distributed.
Furthermore, a principal aim of IVA is the identification of dependent sources
between datasets. Thus, we provide the additional conditions for when the
arbitrary ordering of the sources within each dataset is common. Performance
bounds in terms of the Cramer-Rao lower bound are also provided for the
demixing matrices and interference to source ratio. The performance of two IVA
algorithms are compared to the theoretical bounds.


title: Detecting range expansions from genetic data

abstract:
  We propose a method that uses genetic data to test for the occurrence of a
recent range expansion and to infer the location of the origin of the
expansion. We introduce a statistic for pairs of populations $\psi$ (the
directionality index) that detects asymmetries in the two-dimensional allele
frequency spectrum caused by the series of founder events that happen during an
expansion. Such asymmetry arises because low frequency alleles tend to be lost
during founder events, thus creating clines in the frequencies of surviving
low-frequency alleles. Using simulations, we further show that $\psi$ is more
powerful for detecting range expansions than both $F_{ST}$ and clines in
heterozygosity. We illustrate the utility of $\psi$ by applying it to a data
set from modern humans and show how we can include more complicated scenarios
such as multiple expansion origins or barriers to migration in the model.


title: Conspiratorial cosmology - the case against the Universe

abstract:
  Based on the cosmological results of the Planck Mission, we show that all
parameters describing our Universe within the \Lambda CDM model can be
constructed from a small set of numbers known from conspiracy theory. Our
finding is confirmed by recent data from high energy particle physics. This
clearly demonstrates that our Universe is a plot initiated by an unknown
interest group or lodge. We analyse possible scenarios for this conspiracy, and
conclude that the belief in the existence of our Universe is an illusion, as
previously assumed by ancient philosophers, 20th century science fiction
authors and contemporary film makers.


title:
Optimality of $\ell_2/\ell_1$-optimization block-length dependent
  thresholds

abstract:
  The recent work of \cite{CRT,DonohoPol} rigorously proved (in a large
dimensional and statistical context) that if the number of equations
(measurements in the compressed sensing terminology) in the system is
proportional to the length of the unknown vector then there is a sparsity
(number of non-zero elements of the unknown vector) also proportional to the
length of the unknown vector such that $\ell_1$-optimization algorithm succeeds
in solving the system. In more recent papers
\cite{StojnicCSetamBlock09,StojnicICASSP09block,StojnicJSTSP09} we considered
under-determined systems with the so-called \textbf{block}-sparse solutions. In
a large dimensional and statistical context in \cite{StojnicCSetamBlock09} we
determined lower bounds on the values of allowable sparsity for any given
number (proportional to the length of the unknown vector) of equations such
that an $\ell_2/\ell_1$-optimization algorithm succeeds in solving the system.
These lower bounds happened to be in a solid numerical agreement with what one
can observe through numerical experiments. Here we derive the corresponding
upper bounds. Moreover, the upper bounds that we obtain in this paper match the
lower bounds from \cite{StojnicCSetamBlock09} and ultimately make them optimal.


title:
A performance analysis framework for SOCP algorithms in noisy compressed
  sensing

abstract:
  Solving under-determined systems of linear equations with sparse solutions
attracted enormous amount of attention in recent years, above all, due to work
of \cite{CRT,CanRomTao06,DonohoPol}. In \cite{CRT,CanRomTao06,DonohoPol} it was
rigorously shown for the first time that in a statistical and large dimensional
context a linear sparsity can be recovered from an under-determined system via
a simple polynomial $\ell_1$-optimization algorithm. \cite{CanRomTao06} went
even further and established that in \emph{noisy} systems for any linear level
of under-determinedness there is again a linear sparsity that can be
\emph{approximately} recovered through an SOCP (second order cone programming)
noisy equivalent to $\ell_1$. Moreover, the approximate solution is (in an
$\ell_2$-norm sense) guaranteed to be no further from the sparse unknown vector
than a constant times the noise. In this paper we will also consider solving
\emph{noisy} linear systems and present an alternative statistical framework
that can be used for their analysis. To demonstrate how the framework works we
will show how one can use it to precisely characterize the approximation error
of a wide class of SOCP algorithms. We will also show that our theoretical
predictions are in a solid agrement with the results one can get through
numerical simulations.


title: Meshes that trap random subspaces

abstract:
  In our recent work \cite{StojnicCSetam09,StojnicUpper10} we considered
solving under-determined systems of linear equations with sparse solutions. In
a large dimensional and statistical context we proved results related to
performance of a polynomial $\ell_1$-optimization technique when used for
solving such systems. As one of the tools we used a probabilistic result of
Gordon \cite{Gordon88}. In this paper we revisit this classic result in its
core form and show how it can be reused to in a sense prove its own optimality.


title:
Linear under-determined systems with sparse solutions: Redirecting a
  challenge?

abstract:
  Seminal works \cite{CRT,DonohoUnsigned,DonohoPol} generated a massive
interest in studying linear under-determined systems with sparse solutions. In
this paper we give a short mathematical overview of what was accomplished in
last 10 years in a particular direction of such a studying. We then discuss
what we consider were the main challenges in last 10 years and give our own
view as to what are the main challenges that lie ahead. Through the
presentation we arrive to a point where the following natural rhetoric question
arises: is it a time to redirect the main challenges? While we can not provide
the answer to such a question we hope that our small discussion will stimulate
further considerations in this direction.


title:
The GAPS programme with HARPS-N at TNG. I: Observations of the
  Rossiter-McLaughlin effect and characterisation of the transiting system
  Qatar-1

abstract:
  A long-term multi-purpose observational programme has started with
HARPS-N@TNG aimed to characterise the global architectural properties of
exoplanetary systems. In this first paper we fully characterise the transiting
system Qatar-1. We exploit HARPS-N high-precision radial velocity measurements
obtained during a transit to measure the Rossiter-McLaughlin effect in the
Qatar-1 system, and out-of-transit measurements to redetermine the
spectroscopic orbit. New photometric transit light-curves are analysed and a
spectroscopic characterisation of the host star atmospheric parameters is
performed based on various methods (line equivalent width ratios, spectral
synthesis, spectral energy distribution). We achieved a significant improvement
in the accuracy of the orbital parameters and derived the spin-orbit alignment
of the system; this information, combined with the spectroscopic determination
of the host star properties, allows us to derive the fundamental physical
parameters for star and planet (masses and radii). The orbital solution for the
Qatar-1 system is consistent with a circular orbit and the system presents a
sky-projected obliquity of lambda = -8.4+-7.1 deg. The planet, with a mass of
1.33+-0.05 M_J, is found to be significantly more massive than previously
reported. The host star is confirmed to be metal-rich ([Fe/H]= 0.20+-0.10) and
slowly rotating (vsinI = 1.7+-0.3 km/s), though moderately active, as indicated
by strong chromospheric emission in the Ca II H&K line cores (logR'_HK about
-4.60). The system is well aligned and fits well within the general lambda vs
Teff trend. We definitely rule out any significant orbital eccentricity. The
evolutionary status of the system is inferred based on gyrochronology, and the
present orbital configuration and timescale for orbital decay are discussed in
terms of star-planet tidal interactions.


title: Ultra-strong MgII Absorbers as a Signature of Cool Intragroup Gas

abstract:
  We present the results of a spectroscopic survey of galaxies in the vicinity
of an ultra-strong MgII \lambda\lambda 2786,2803 absorber of rest-frame
absorption equivalent width W_r(2796)=4.2\AA\ at z=0.5624. This absorber was
originally found at projected separation \rho=246 kpc of a luminous red galaxy
(LRG) at z=0.5604. Magellan IMACs spectroscopy has revealed two galaxies at
\rho < 60 kpc (z=0.5623 and z=0.5621) and a third one at \rho=209 kpc
(z=0.5623) near the redshift of the absorber.These findings indicate that the
absorbing gas resides in a group environment. Combining SDSS broadband
photometry with additional B-, K_s-band images and optical spectroscopy, we
perform a stellar population synthesis analysis of the group members to
characterize their star formation histories, on-going star formation rates
(SFR), and stellar masses. We find that the two group members at \rho < 60 kpc
are best characterized by old stellar populations (>1 Gyr) and little on-going
star formation activity (SFR<2.9 \msun/yr), while the third object at \rho=209
kpc exhibit [OII]- and continuum-derived SFR consistent with SFR>3.0 \msun/yr.
Including the two ultra-strong MgII absorbers analyzed by Nestor et al. (2011),
this is the third ultra-strong MgII absorber for which a detailed study of the
galactic environment is available. All three aborbers are found in galaxy
groups. We examine different physical mechanisms giving rise to the absorbing
gas including starburst driven-outflows, cold filaments, extended rotating
disks, and stripped gas. We argue that the large equivalent width observed in
these absorbers is more likely due to the gas dynamics of the intragroup medium
rather than driven by starburst outflows.


title: Aging Logarithmic Galilean Field Theories

abstract:
  We analytically compute correlation and response functions of scalar
operators for the systems with Galilean and corresponding aging symmetries for
general spatial dimensions $d$ and dynamical exponent $z$, along with their
logarithmic and logarithmic squared extensions, using the gauge/gravity
duality. These non-conformal extensions of the aging geometry are marked by two
dimensionful parameters, eigenvalue $\mathcal M$ of an internal coordinate and
aging parameter $\alpha$.
  We further perform systematic investigations on two-time response functions
for general $d$ and $z$, and identify the growth exponent as a function of the
scaling dimensions $\Delta$ of the dual field theory operators and aging
parameter $\alpha$ in our theory. The initial growth exponent is only
controlled by $\Delta$, while its late time behavior by $\alpha$ as well as
$\Delta$. These behaviors are separated by a time scale order of the waiting
time. We attempt to make contact our results with some field theoretical growth
models, such as Kim-Kosterlitz model at higher number of spatial dimensions
$d$.


title: Effect of sine-Gaussian glitches on searches for binary coalescence

abstract:
  We investigate the effect of an important class of glitches occurring in the
detector data on matched filter searches of gravitational waves from coalescing
compact binaries in the advanced detector era. The glitches, which can be
modeled as sine-Gaussians, can produce triggers with significant time delays
and thus have important bearing on veto procedures as will be described in the
paper. We provide approximated analytical estimates of the trigger SNR and time
as a function of the parameters describing the sine-Gaussian (center time,
center frequency and Q-factor) and the inspiral waveform (chirp mass). We
validate our analytical predictions through simple numerical simulations,
performed by filtering noiseless sine-Gaussians with the inspiral matched
filter and recovering the time and value of the maximum of the resulting SNR
time series. Although we identify regions of the parameter space in which each
approximation no longer reproduces the numerical results, the approximations
complement each other and together effectively cover the whole parameter space.


title: Catastrophic Consequences of Kicking the Chameleon

abstract:
  The physics of the "dark energy" that drives the current cosmological
acceleration remains mysterious, and the dark sector may involve new light
dynamical fields. If these light scalars couple to matter, a screening
mechanism must prevent them from mediating an unacceptably strong fifth force
locally. Here we consider a concrete example: the chameleon mechanism. We show
that the same coupling between the chameleon field and matter employed by the
screening mechanism also has catastrophic consequences for the chameleon during
the Universe's first minutes. The chameleon couples to the trace of the
stress-energy tensor, which is temporarily non-zero in a radiation-dominated
universe whenever a particle species becomes non-relativistic. These "kicks"
impart a significant velocity to the chameleon field, causing its effective
mass to vary non-adiabatically and resulting in the copious production of
quantum fluctuations. Dissipative effects strongly modify the background
evolution of the chameleon field, invalidating all previous classical
treatments of chameleon cosmology. Moreover, the resulting fluctuations have
extremely high characteristic energies, which casts serious doubt on the
validity of the effective theory. Our results demonstrate that quantum particle
production can profoundly affect scalar-tensor gravity, a possibility not
previously considered. Working in this new context, we also develop the theory
and numerics of particle production in the regime of strong dissipation.


title:
The EGNoG Survey: Molecular Gas in Intermediate-Redshift Star-Forming
  Galaxies

abstract:
  We present the Evolution of molecular Gas in Normal Galaxies (EGNoG) survey,
an observational study of molecular gas in 31 star-forming galaxies from z=0.05
to z=0.5, with stellar masses of (4-30)x10^10 M_Sun and star formation rates of
4-100 M_Sun yr^-1. This survey probes a relatively un-observed redshift range
in which the molecular gas content of galaxies is expected to have evolved
significantly. To trace the molecular gas in the EGNoG galaxies, we observe the
CO(1-0) and CO(3-2) rotational lines using the Combined Array for Research in
Millimeter-wave Astronomy (CARMA). We detect 24 of 31 galaxies and present
resolved maps of 10 galaxies in the lower redshift portion of the survey. We
use a bimodal prescription for the CO to molecular gas conversion factor, based
on specific star formation rate, and compare the EGNoG galaxies to a large
sample of galaxies assembled from the literature. We find an average molecular
gas depletion time of 0.76 \pm 0.54 Gyr for normal galaxies and 0.06 \pm 0.04
Gyr for starburst galaxies. We calculate an average molecular gas fraction of
7-20% at the intermediate redshifts probed by the EGNoG survey. By expressing
the molecular gas fraction in terms of the specific star formation rate and
molecular gas depletion time (using typical values), we also calculate the
expected evolution of the molecular gas fraction with redshift. The predicted
behavior agrees well with the significant evolution observed from z~2.5 to
today.


title:
Controlling and measuring quantum transport of heat in trapped-ion
  crystals

abstract:
  Measuring heat flow through nanoscale systems poses formidable practical
difficulties as there is no `ampere meter' for heat. We propose to overcome
this problem by realizing heat transport through a chain of trapped ions. Laser
cooling the chain edges to different temperatures induces a current of local
vibrations (vibrons). We show how to efficiently control and measure this
current, including fluctuations, by coupling vibrons to internal ion states.
This demonstrates that ion crystals provide a suitable platform for studying
quantum transport, e.g., through thermal analogues of quantum wires and quantum
dots. Notably, ion crystals may give access to measurements of the elusive
large fluctuations of bosonic currents and the onset of Fourier's law. These
results are supported by numerical simulations for a realistic implementation
with specific ions and system parameters.


title: Using Memory-Protection to Simplify Zero-copy Operations

abstract:
  High performance networks (e.g. Infiniband) rely on zero-copy operations for
performance. Zero-copy operations, as the name implies, avoid copying buffers
for sending and receiving data. Instead, hardware devices directly read and
write to application specified areas of memory. Since these networks can send
and receive at nearly the same speed as the memory bus inside machines,
zero-copy operations are necessary to achieve peak performance for many
applications.
  Unfortunately, programming with zero-copy APIs is a *giant pain*. Users must
carefully avoid using buffers that may be accessed by a device. Typically this
either results in spaghetti code (where every access to a buffer is checked
before usage), or blocking operations (which pretty much defeat the whole point
of zero-copy).
  We show that by abusing memory protection hardware, we can offer the best of
both worlds: a simple zero-copy mechanism which allows for non-blocking send
and receives while protecting against incorrect accesses.


title: A possible approach on optical analogues of gravitational attractors

abstract:
  In this paper we report on the feasibility of light confinement in orbital
geodesics on stationary, planar, and centro-symmetric refractive index
mappings. Constrained to fabrication and [meta]material limitations, the
refractive index, n, has been bounded to the range: $0.8\leq n(\vec r)\leq
3.5$. Mappings are obtained through the inverse problem to the light geodesics
equations, considering trappings by generalized orbit conditions defined
\emph{a priori}. Our simulation results show that the above mentioned
refractive index distributions trap light in an open orbit manifold, both
perennial and temporal, in regards to initial conditions. Moreover, due to
their characteristics, these mappings could be advantageous to optical
computing and telecommunications, for example, providing an on-demand time
delay or optical memories. Furthermore, beyond their practical applications to
photonics, these mappings set forth an attractive realm to construct a panoply
of celestial mechanics analogies and experiments in the laboratory

categories: math-ph math.MP physics.comp-ph physics.optics


title: ADM reduction of Einstein action and black hole entropy

abstract:
  We reduce the 4D Einstein-Hilbert action to a constant-radius hypersurface of
foliation. The resulting theory is a scalar theory defined on a 3D hypersurface
of the original black hole background, and has an exponential potential. Once
the the hypersurface is located at the Schwarzschild radius, the 3D theory is
effectively reduced to a 2D Liouville type theory. We compute {the entropy
associated with the hypersurface intrinsic degrees of freedom}, and show that
its leading order reproduces the Bekenstein-Hawking area law. The subleading
terms come in logarithm/inverse powers of the area.


title: Quantum curves for simple Hurwitz numbers of an arbitrary base curve

abstract:
  Various generating functions of simple Hurwitz numbers of the projective line
are known to satisfy many properties. They include a heat equation, the
Eynard-Orantin topological recursion, an infinite-order differential equation
called a quantum curve equation, and a Schroedinger like partial differential
equation. In this paper we generalize these properties to simple Hurwitz
numbers with an arbitrary base curve.


title: An extra Z' gauge boson as a source of Higgs particles

abstract:
  Models with extra gauge bosons often require an extended Higgs sector, which
contains a rich spectrum of Higgs bosons with properties that deviate from the
Standard Model (SM). Such Higgs bosons could be searched using standard
mechanisms similar to the SM. However, the existence of the new gauge bosons
could provide new production mechanisms, which could probe the non-standard
origin of the Higgs particle. In this paper we study how the Z' from a model
with extra U(1)' could be used as a source of Higgs bosons. We study 3-bodies
decays of the Z' into a Higgs boson and a top anti-top pair or WW pair, namely
Z'\to t\bar{t} h, WW h. We find that it is possible to get {\Br'}s as high as
10^{-2} for these modes, which could be studied at future colliders. We also
study the production of the Higgs bosons in association with the Z vector boson
at a linear collider, through the reaction e^+ e^- \to Z, Z'\to Z+h, including
both the resonant and the non-resonant effects.


title: Low Energy Probes of Physics Beyond the Standard Model

abstract:
  Low-energy tests of fundamental symmetries and studies of neutrino properties
provide a powerful window on physics beyond the Standard Model (BSM). In this
article, we provide a basic theoretical framework for a subsequent set of
articles that review the progress and opportunities in various aspects of the
low-energy program. We illustrate the physics reach of different low-energy
probes in terms of an effective BSM mass scale and illustrate how this reach
matches and, in some cases, even exceeds that accessible at the high energy
frontier.


title:
Statistical inference framework for source detection of contagion
  processes on arbitrary network structures

abstract:
  In this paper we introduce a statistical inference framework for estimating
the contagion source from a partially observed contagion spreading process on
an arbitrary network structure. The framework is based on a maximum likelihood
estimation of a partial epidemic realization and involves large scale
simulation of contagion spreading processes from the set of potential source
locations. We present a number of different likelihood estimators that are used
to determine the conditional probabilities associated to observing partial
epidemic realization with particular source location candidates. This
statistical inference framework is also applicable for arbitrary compartment
contagion spreading processes on networks. We compare estimation accuracy of
these approaches in a number of computational experiments performed with the
SIR (susceptible-infected-recovered), SI (susceptible-infected) and ISS
(ignorant-spreading-stifler) contagion spreading models on synthetic and
real-world complex networks.


title: Age group and gender recognition from human facial images

abstract:
  This work presents an automatic human gender and age group recognition system
based on human facial images. It makes an extensive experiment with row pixel
intensity valued features and Discrete Cosine Transform (DCT) coefficient
features with Principal Component Analysis and k-Nearest Neighbor
classification to identify the best recognition approach. The final results
show approaches using DCT coefficient outperform their counter parts resulting
in a 99% correct gender recognition rate and 68% correct age group recognition
rate (considering four distinct age groups) in unseen test images. Detailed
experimental settings and obtained results are clearly presented and explained
in this report.


title:
Symmetric polynomials, generalized Jacobi-Trudi identities and
  \tau-functions

abstract:
  An element [\Phi] of the Grassmannian of n-dimensional subspaces of the Hardy
space H^2, extended over the field C(x_1,..., x_n), may be associated to any
polynomial basis {\phi} for C(x). The Pl\"ucker coordinates
S^\phi_{\lambda,n}(x_1,..., x_n) of \Phi, labelled by partitions \lambda,
provide an analog of Jacobi's bi-alternant formula, defining a generalization
of Schur polynomials. Applying the recursion relations satisfied by the
polynomial system to the analog of the complete symmetric functions generates a
doubly infinite matrix of symmetric polynomials that determine an element [H]
of the Grassmannian. This is shown to coincide with [\Phi], implying a set of
{\it quantum Jacobi-Trudi identities} that generalize a result obtained by
Sergeev and Veselov for the case of orthogonal polynomials. The symmetric
polynomials S^\phi_{\lambda,n}(x_1,..., x_n) are shown to be KP
(Kadomtsev-Petviashvili) tau-functions in terms of the monomial sums [x] in the
parameters x_a, viewed as KP flow variables. A fermionic operator
representation is derived for these, as well as for the infinite sums
\sum_{\lambda}S_{\lambda,n}^\phi([x]) S^\theta_{\lambda,n} ({\bf t}) associated
to any pair of polynomial bases (\phi, \theta), which are shown to be 2D Toda
lattice \tau-functions. A number of applications are given, including classical
group character expansions, matrix model partition functions and generators for
random processes.


title: Automorphic Equivalence of Many-Sorted Algebras

abstract:
  In the first part of our paper (Sections 1, 2 and 3) we reprove results of B.
Plotkin, G. Zhitomirski. On automorphisms of categories of free algebras of
some varieties, Journal of Algebra, 306:2, (2006), 344 -- 367 for the case of
many-sorted algebras. In the second part of our paper (Section 4) we apply the
results of the first part to the universal algebraic geometry of many-sorted
algebras and refine and reprove results of B. Plotkin, Algebras with the same
(algebraic) geometry, Proceedings of the International Conference on
Mathematical Logic, Algebra and Set Theory, dedicated to 100 anniversary of
P.S. Novikov, Proceedings of the Steklov Institute of Mathematics, MIAN, 242
(2003), 127 -- 207 and A. Tsurkov, Automorphic equivalence of algebras,
International Journal of Algebra and Computation. 17:5/6, (2007), 1263 -- 1271
for these algebras. In the third part of this paper (Section 5) we consider
some varieties of many-sorted algebras. We prove that automorphic equivalence
coincide with geometric equivalence in the variety of the all actions of
semigroups over sets and in the variety of the all automatons. We also consider
the variety of the all representations of groups and the all representations of
Lie algebras. For both these varieties we give an examples of the
representations which are automorphically equivalent but not geometrically
equivalent.


title:
D3/D7 Branes at Singularities: Constraints from Global Embedding and
  Moduli Stabilisation

abstract:
  In the framework of type IIB string compactifications on Calabi-Yau
orientifolds we describe how to construct consistent global embeddings of
models with fractional D3-branes and connected `flavour' D7-branes at del Pezzo
singularities with moduli stabilisation. Our results are applied to build an
explicit compact example with a left-right symmetric model at a dP_0
singularity which features three families of chiral matter and gauge coupling
unification at the intermediate scale. We show how to stabilise the moduli
obtaining a controlled de Sitter minimum and spontaneous supersymmetry
breaking. We find an interesting non-trivial dynamical relation between the
requirement of TeV-scale soft terms and the correct phenomenological values of
the unified gauge coupling and unification scale.


title:
The two-dimensional Gabor function adapted to natural image statistics:
  A model of simple-cell receptive fields and sparse structure in images

abstract:
  The two-dimensional Gabor function is adapted to natural image statistics,
leading to a tractable probabilistic generative model that can be used to model
simple-cell receptive-field profiles, or generate basis functions for sparse
coding applications. Learning is found to be most pronounced in three
Gabor-function parameters representing the size and spatial frequency of the
two-dimensional Gabor function, and characterized by a non-uniform probability
distribution with heavy tails. All three parameters are found to be strongly
correlated: resulting in a basis of multiscale Gabor functions with similar
aspect ratios, and size-dependent spatial frequencies. A key finding is that
the distribution of receptive-field sizes is scale-invariant over a wide range
of values, so there is no characteristic receptive-field size selected by
natural image statistics. The Gabor-function aspect ratio is found to be
approximately conserved by the learning rules and is therefore not
well-determined by natural image statistics. This allows for three distinct
solutions: a basis of Gabor functions with sharp orientation resolution at the
expense of spatial-frequency resolution; a basis of Gabor functions with sharp
spatial-frequency resolution at the expense of orientation resolution; or a
basis with unit aspect ratio. Arbitrary mixtures of all three cases are also
possible. Two parameters controlling the shape of the marginal distributions in
a probabilistic generative model fully account for all three solutions. The
best-performing probabilistic generative model for sparse coding applications
is found to be a Gaussian copula with Pareto marginal probability density
functions.


title:
Topology trivialization and large deviations for the minimum in the
  simplest random optimization

abstract:
  Finding the global minimum of a cost function given by the sum of a quadratic
and a linear form in N real variables over (N-1)- dimensional sphere is one of
the simplest, yet paradigmatic problems in Optimization Theory known as the
"trust region subproblem" or "constraint least square problem". When both terms
in the cost function are random this amounts to studying the ground state
energy of the simplest spherical spin glass in a random magnetic field. We
first identify and study two distinct large-N scaling regimes in which the
linear term (magnetic field) leads to a gradual topology trivialization, i.e.
reduction in the total number N_{tot} of critical (stationary) points in the
cost function landscape. In the first regime N_{tot} remains of the order $N$
and the cost function (energy) has generically two almost degenerate minima
with the Tracy-Widom (TW) statistics. In the second regime the number of
critical points is of the order of unity with a finite probability for a single
minimum. In that case the mean total number of extrema (minima and maxima) of
the cost function is given by the Laplace transform of the TW density, and the
distribution of the global minimum energy is expected to take a universal
scaling form generalizing the TW law. Though the full form of that distribution
is not yet known to us, one of its far tails can be inferred from the large
deviation theory for the global minimum. In the rest of the paper we show how
to use the replica method to obtain the probability density of the minimum
energy in the large-deviation approximation by finding both the rate function
and the leading pre-exponential factor.

categories: cond-mat.dis-nn cond-mat.stat-mech math-ph math.MP math.OC


title:
Dependence on state preparation of noise induced effects in multiqubit
  systems

abstract:
  The perturbation of multiqubit systems by an external noise can induce
various effects like decoherence, stochastic resonance and anti-resonance, and
noise-shielding. We investigate how the appearance of these effects on
disentanglement time depends on the initial preparation of the systems. We
present results for 2, 3 and 4-qubit chains in various arrangements and observe
a clear dependence on the combination of initial geometry of the state space
and the placement of noise. Finally, we see that temperature can play a
constructive role for the control of these noise induced effects.


title: Socle pairings on tautological rings

abstract:
  We study some aspects of the $\lambda_g$ pairing on the tautological ring of
$M_g^c$, the moduli space of genus $g$ stable curves of compact type. We
consider pairing kappa classes with pure boundary strata, all tautological
classes supported on the boundary, or the full tautological ring. We prove that
the rank of this restricted pairing is equal in the first two cases and has an
explicit formula in terms of partitions, while in the last case the rank
increases by precisely the rank of the $\lambda_g\lambda_{g - 1}$ pairing on
the tautological ring of $M_g$.


title: Periodic solutions in an array of coupled FitzHugh-Nagumo cells

abstract:
  We analyse the dynamics of an array of $N^2$ identical cells coupled in the
shape of a torus. Each cell is a 2-dimensional ordinary differential equation
of FitzHugh-Nagumo type and the total system is
$\mathbb{Z}_N\times\mathbb{Z}_N-$symmetric. The possible patterns of
oscillation, compatible with the symmetry, are described. The types of patterns
that effectively arise through Hopf bifurcation are shown to depend on the
signs of the coupling constants, under conditions ensuring that the equations
have only one equilibrium state.


title: Carving Out Parameter Space in Type-II Two Higgs Doublets Model

abstract:
  We analyze the Type-II two Higgs doublets model in light of the newly
discovered Higgs-like particle with mass 125 GeV. The observed 125 GeV particle
is identified with the light CP-even Higgs boson in the two Higgs doublets
model. We study the parameter space of the model consistent with the Higgs
data, branching ratio of $\bar{B}\to X_s\gamma$ as well as precision
electroweak measurements. We also incorporate theoretical constraints---
perturbativity of the couplings and vacuum stability, in our study. We find
that only a small parameter space of the model remains viable. The
phenomenology of the heavy Higgs bosons in the surviving parameter space is
studied.


title: Weak Values Technique for Velocity Measurements

abstract:
  In a recent letter, Brunner and Simon propose an interferometric scheme using
imaginary weak values with a frequency-domain analysis to outperform standard
interferometry in longitudinal phase shifts [N. Brunner and C. Simon, Phys.
Rev. Lett {\bf105} (2010)]. Here we demonstrate an interferometric scheme
combined with a time-domain analysis to measure longitudinal velocities. The
technique employs the near-destructive interference of non-Fourier limited
pulses, one Doppler shifted due to a moving mirror, in a Michelson
interferometer. We achieve a velocity measurement of 400 fm/s and show our
estimator to be efficient by reaching its Cram\'{e}r-Rao bound.


title:
Note on Combinatorial Engineering Frameworks for Hierarchical Modular
  Systems

abstract:
  The paper briefly describes a basic set of special combinatorial engineering
frameworks for solving complex problems in the field of hierarchical modular
systems. The frameworks consist of combinatorial problems (and corresponding
models), which are interconnected/linked (e.g., by preference relation).
Mainly, hierarchical morphological system model is used. The list of basic
standard combinatorial engineering (technological) frameworks is the following:
(1) design of system hierarchical model, (2) combinatorial synthesis
('bottom-up' process for system design), (3) system evaluation, (4) detection
of system bottlenecks, (5) system improvement (re-design, upgrade), (6)
multi-stage design (design of system trajectory), (7) combinatorial modeling of
system evolution/development and system forecasting. The combinatorial
engineering frameworks are targeted to maintenance of some system life cycle
stages. The list of main underlaying combinatorial optimization problems
involves the following: knapsack problem, multiple-choice problem, assignment
problem, spanning trees, morphological clique problem.


title:
The Sense of Place: Grid Cells in the Brain and the Transcendental
  Number e

abstract:
  Grid cells in the brain respond when an animal occupies a periodic lattice of
"grid fields" during spatial navigation. The grid scale varies along the
dorso-ventral axis of the entorhinal cortex. We propose that the grid system
minimizes the number of neurons required to encode location with a given
resolution. We derive several predictions that match recent experiments: (i)
grid scales follow a geometric progression, (ii) the ratio between adjacent
grid scales is the square root of e for idealized neurons, and robustly lies in
the range 1.4-1.7 for realistic neurons, (iii) the scale ratio varies modestly
within and between animals, (iv) the ratio between grid scale and individual
grid field widths at that scale also lies in this range, (v) grid fields lie on
a triangular lattice. The theory also predicts the optimal grids in one and
three dimensions, and the total number of discrete scales.


title: An immersed $S^2$ self-shrinker

abstract: We construct an immersed and non-embedded $S^2$ self-shrinker.


title: The shape of spins

abstract:
  After the discovery of a Higgs-like particle at the LHC, the determination of
its spin quantum numbers across different channels will be the next step in
arriving at a more precise understanding of the new state and its role in
electroweak symmetry breaking. Event shape observables have been shown to
provide extremely sensitive observables for the discrimination of the scalar
Higgs boson's CP quantum numbers as a consequence of the different radiation
patterns of Higgs production via gluon fusion vs. weak boson fusion in the
$pp\to X+2j$ selection. We show that a similar strategy serves to constrain the
spin quantum numbers of the discovered particle as a function of the involved
couplings. We also discuss the prospects of applying a similar strategy to
future discoveries of Higgs-like particles.


title:
Generation and Bistability of a Waveguide Nanoplasma Observed by
  Enhanced Extreme-Ultraviolet Fluorescence

abstract:
  We present a study of the highly nonlinear optical excitation of noble gases
in tapered hollow waveguides using few-femtosecond laser pulses. The local
plasmonic field enhancement induces the generation of a nanometric plasma,
resulting in incoherent extreme-ultraviolet fluorescence from optical
transitions of neutral and ionized xenon, argon, and neon. Despite sufficient
intensity in the waveguide, high-order harmonic generation is not observed. The
fluorescent emission exhibits a strong bistability manifest as an intensity
hysteresis, giving strong indications for multistep collisional excitations.


title: Translation-Invariant Shrinkage/Thresholding of Group Sparse Signals

abstract:
  This paper addresses signal denoising when large-amplitude coefficients form
clusters (groups). The L1-norm and other separable sparsity models do not
capture the tendency of coefficients to cluster (group sparsity). This work
develops an algorithm, called 'overlapping group shrinkage' (OGS), based on the
minimization of a convex cost function involving a group-sparsity promoting
penalty function. The groups are fully overlapping so the denoising method is
translation-invariant and blocking artifacts are avoided. Based on the
principle of majorization-minimization (MM), we derive a simple iterative
minimization algorithm that reduces the cost function monotonically. A
procedure for setting the regularization parameter, based on attenuating the
noise to a specified level, is also described. The proposed approach is
illustrated on speech enhancement, wherein the OGS approach is applied in the
short-time Fourier transform (STFT) domain. The denoised speech produced by OGS
does not suffer from musical noise.


title: Tight bound on relative entropy by entropy difference

abstract:
  We prove a lower bound on the relative entropy between two finite-dimensional
states in terms of their entropy difference and the dimension of the underlying
space. The inequality is tight in the sense that equality can be attained for
any prescribed value of the entropy difference, both for quantum and classical
systems. We outline implications for information theory and thermodynamics,
such as a necessary condition for a process to be close to thermodynamic
reversibility, or an easily computable lower bound on the classical channel
capacity. Furthermore, we derive a tight upper bound, uniform for all states of
a given dimension, on the variance of the surprisal, whose thermodynamic
meaning is that of heat capacity.

categories: quant-ph cond-mat.stat-mech cs.IT math.IT


title: Dynamic response of a spin-1/2 Kondo singlet

abstract:
  We present a study of spin 1/2 Kondo singlets in single electron transistors
under a microwave frequency bias excitation. We compare time-averaged
conductance $G$ to predicted universal response with respect to microwave
frequency, oscillation amplitude and the Kondo temperature and find a
non-adiabatic response when the microwave photon energy $hf$ is comparable to
the Kondo temperature $k_B T_K$. We show that our measurements are
qualitatively consistent with the predictions for the radiation-induced
decoherence rate of the Kondo spin.


title: Common origin of superluminal neutrinos and DAMA annual modulation

abstract:
  We suggest that the recently observed superluminal neutrino propagation
observed by OPERA may have an environmental origin that can simultaneously
explain the DAMA/LIBRA annual modulation. Our proposal can be unambiguously
tested by the prediction that OPERA will also observe an annual modulation in
the speed of neutrinos. Experiments geographically distant from Gran Sasso will
however not be able to observe these effects. We do not rely upon any violation
of Lorentz symmetry except for spontaneous breaking of translational
invariance. We discuss implications for the CRESST experiment, also located at
Gran Sasso.


title: Graphene-based charge sensors

abstract:
  We discuss graphene nanoribbon-based charge sensors and focus on their
functionality in the presence of external magnetic fields and high frequency
pulses applied to a nearby gate electrode. The charge detectors work well with
in-plane magnetic fields of up to 7 T and pulse frequencies of up to 20 MHz. By
analyzing the step height in the charge detector's current at individual
charging events in a nearby quantum dot, we determine the ideal operation
conditions with respect to the applied charge detector bias. Average charge
sensitivities of 1.3*10^-3 e/sqrt{Hz} can be achieved. Additionally, we
investigate the back action of the charge detector current on the quantum
transport through a nearby quantum dot. By setting the charge detector bias
from 0 to 4.5 mV, we can increase the Coulomb peak currents measured at the
quantum dot by a factor of around 400. Furthermore, we can completely lift the
Coulomb blockade in the quantum dot.


title:
Manipulation of skyrmions in nanodisks with a current pulse and skyrmion
  rectifier

abstract:
  A skyrmion in a nanosized disk of a chiral magnet can be used as a bit of
information. To this end, it is desirable to control the creation and removal
of a skyrmion only by currents without using external magnetic fields. Here we
propose to create a skyrmion by applying a current pulse to a nanodisk. The
skyrmion can be removed from the disk by applying a dc current. We show that
the dynamics of the created skyrmion can lead to a rectification effect, in
which a dc voltage is generated by the motion of skyrmion in the presence of an
ac current.


title:
On fluctuations of traces of large matrices over a non-commutative
  algebra

abstract:
  The paper investigates the asymptotic behavior of (non-normalized) traces of
certain classes of matrices with non-commutative random variables as entries.
We show that, unlike in the commutative framework, the asymptotic behavior of
matrices with free circular, respectively with Bernoulli distributed Boolean
independent entries is described in terms of free, respectively Boolean
cumulants. We also present an exemple of relation of monotone independence
arising from the study of Boolean independence.


title: Towards Efficient Computation of Functional Determinants in QM and QFT

abstract:
  We present an overview of the existing methods for computing functional
determinants, and outline a possible way forward for Hamiltonians of higher
dimensions without radial symmetry.


title:
Shimura modular curves and asymptotic symmetric tensor rank of
  multiplication in any finite field

abstract:
  We obtain new asymptotical bounds for the symmetric tensor rank of
multiplication in any finite extension of any finite field $\F_q$. In this aim,
we use the symmetric Chudnovsky-type generalized algorithm applied on a family
of Shimura modular curves defined over $\F_{q^2}$ attaining the Drinfeld-Vladut
bound and on the descent of this family over the definition field $\F_q$.


title: Hilbert Series of Residual Intersections

abstract:
  We find explicit formulas for the Hilbert series of residual intersections of
a scheme in terms of the Hilbert series of its conormal modules. In a previous
paper we proved that such formulas should exist. We give applications to the
dimension of secant varieties of surfaces and three-folds.


title: Rarefaction waves in nonlocal convection-diffusion equations

abstract:
  We consider the "convection-diffussion" equation $u_t=J*u-u-uu_x,$ where $J$
is a probability density. We supplement this equation with step-like initial
conditions and prove a convergence of corresponding solution towards a
rarefaction wave, i.e. a unique entropy solution of the Riemann problem for the
nonviscous Burgers equation. Methods and tools used in this paper are inspired
by those used in [Karch, Miao and Xu, SIAM J. Math. Anal. {\bf 39} (2008), no.
5, 1536--1549.], where the fractal Burgers equation was studied.


title:
On exotic sphere fibrations, topological phases, and edge states in
  physical systems

abstract:
  We suggest that exotic sphere fibrations can be mapped to band topologies in
condensed matter systems. These fibrations can correspond to geometric phases
of two double bands or state vector bases with second Chern numbers m+n and -n
respectively. They can be related to topological insulators, magneto-electric
effects, and photonic crystals with special edge states. We also consider
time-reversal symmetry breaking perturbations of topological insulator, and
heterostructures of topological insulators with normal insulators and with
superconductors. We consider periodic TI/NI/TI/NI' heterostuctures, and
periodic TI/SC/TI/SC' heterostuctures. They also give rise to models of Weyl
semimetals which have thermal and electrical transports.


title: Intrinsic spin requires gravity with torsion and curvature

abstract:
  We show that the intrinsic angular momentum of matter in curved spacetime
requires the metric-affine formulation of gravity, in which the antisymmetric
part of the affine connection (the torsion tensor) is not constrained to be
zero but is a variable in the principle of stationary action. Regarding the
tetrad and spin connection (or the metric and torsion tensors) as independent
variables gives the correct generalization of the conservation law for the
total (orbital plus intrinsic) angular momentum to the presence of the
gravitational field. The metric-affine formulation extends general relativity
to the simplest theory of gravity with intrinsic spin: the
Einstein-Cartan-Sciama-Kibble theory. We also show that teleparallel gravity,
which constrains the connection by setting the curvature tensor to zero, is
inconsistent with the conservation of the total angular momentum.


title: On $L^p$ resolvent estimates for elliptic operators on compact manifolds

abstract:
  We prove uniform $L^p$ estimates for resolvents of higher order elliptic
self-adjoint differential operators on compact manifolds without boundary,
generalizing a corresponding resul of [3] in the case of Laplace-- Beltrami
operators on Riemannian manifolds. In doing so, we follow the methods,
developed in [1] very closely. We also show that spectral regions in our $L^p$
resolvent estimates are optimal.


title:
Suppression of Ion Transport due to Long-Lived Sub-Wavelength
  Localization by an Optical Lattice

abstract:
  We report the localization of an ion by a one-dimensional optical lattice in
the presence of an applied external force. The ion is confined radially by a
radiofrequency trap and axially by a combined electrostatic and optical-lattice
potential. The ion is cooled using a resolved Raman sideband technique to a
mean vibrational number <n> = 0.6 \pm 0.1 along the optical lattice. We
implement a detection method to monitor the position of the ion subject to a
periodic electrical driving force with a resolution down to \lambda/40, and
demonstrate suppression of the driven ion motion and localization to a single
lattice site on time scales of up to 10 milliseconds. This opens new
possibilities for studying many-body systems with long-range interactions in
periodic potentials.


title: Spectral extremal problems for hypergraphs

abstract:
  In this paper we consider spectral extremal problems for hypergraphs. We give
two general criteria under which such results may be deduced from `strong
stability' forms of the corresponding (pure) extremal results. These results
hold for the \alpha-spectral radius defined using the \alpha-norm for any
\alpha>1; the usual spectrum is the case \alpha=2.
  Our results imply that any hypergraph Tur\'{a}n problem which has the
stability property and whose extremal construction satisfies some rather mild
continuity assumptions admits a corresponding spectral result. A particular
example is to determine the maximum \alpha-spectral radius of any 3-uniform
hypergraph on n vertices not containing the Fano plane, when n is sufficiently
large. Another is to determine the maximum \alpha-spectral radius of any graph
on n vertices not containing some fixed colour-critical graph, when n is
sufficiently large; this generalizes a theorem of Nikiforov who proved stronger
results in the case \alpha=2. We also obtain an \alpha-spectral version of the
Erd\H{o}s-Ko-Rado theorem on t-intersecting k-uniform hypergraphs.


title: A Short Remark on the Polaron in the Semi-relativistic Pauli-Fierz Model

abstract:
  We consider the polaron of the spinless semi-relativistic Pauli-Fierz model.
The Hamiltonian of the model is defined by $H(\mathbf{P}) =
\sqrt{(\mathbf{P}-d\Gamma(\mathbf{k}) + e\bA)^2 + M^2} + d\Gamma(\omega_m)$,
where $\mathbf{P}\in\mathbb{R}^3$ is the momentum of the polaron,
$d\Gamma(\cdot)$ denotes the second quantization operator and
$\omega_m=|\mathbf{k}|+m$ denotes the dispersion relation of the photon with
virtual mass $m\geq 0$. Let $E(\mathbf{P})$ be the lowest energy of
$H(\mathbf{P})$. In this paper, we prove the inequality $E(\mathbf{P} -
\mathbf{k}) - E(\mathbf{P}) + \omega_m(\mathbf{k}) \geq m$, for all
$\mathbf{P}, \mathbf{k}\in\mathbb{R}^3$.


title:
H-loop Histidine Catalyzes ATP Hydrolysis in the E. coli ABC-Transporter
  HlyB

abstract:
  Adenosine triphosphate (ATP)-binding cassette (ABC) transporters form a
family of molecular motor proteins that couple ATP hydrolysis to substrate
translocation across cell membranes. Each nucleotide binding domain of
ABC-transporters contains a highly conserved H-loop Histidine residue, whose
precise mechanistic role to motor functions has remained elusive. By using
combined quantum mechanical and molecular mechanical calculations, we showed
that the conserved H-loop residue H662 in E. coli HlyB, a bacterial ABC
transporter, can act first as a general acid and then as a general base to
facilitate proton transfers in ATP hydrolysis. Without the assistance of H662,
direct proton transfer from the lytic water to ATP results in a greatly
elevated barrier height. Our findings suggest that the essential function of
the H-loop residue H662 is to provide a "chemical linchpin" that shuttles
protons between reactants through a relay mechanism, thereby catalyzing ATP
hydrolysis in HlyB.


title:
Wang's B machines are efficiently universal, as is Hasenjaeger's small
  universal electromechanical toy

abstract:
  In the 1960's Gisbert Hasenjaeger built Turing Machines from
electromechanical relays and uniselectors. Recently, Glaschick reverse
engineered the program of one of these machines and found that it is a
universal Turing machine. In fact, its program uses only four states and two
symbols, making it a very small universal Turing machine. (The machine has
three tapes and a number of other features that are important to keep in mind
when comparing it to other small universal machines.) Hasenjaeger's machine
simulates Hao Wang's B machines, which were proved universal by Wang.
Unfortunately, Wang's original simulation algorithm suffers from an exponential
slowdown when simulating Turing machines. Hence, via this simulation,
Hasenjaeger's machine also has an exponential slowdown when simulating Turing
machines. In this work, we give a new efficient simulation algorithm for Wang's
B machines by showing that they simulate Turing machines with only a polynomial
slowdown. As a second result, we find that Hasenjaeger's machine also
efficiently simulates Turing machines in polynomial time. Thus, Hasenjaeger's
machine is both small and fast. In another application of our result, we show
that Hooper's small universal Turing machine simulates Turing machines in
polynomial time, an exponential improvement.


title: L\"{u}ders Theorem for Unsharp Quantum Measurements

abstract:
  A theorem of L\"{u}ders states that an ideal measurement of a sharp discrete
observable does not alter the statistics of another sharp observable if, and
only if, the two observables commute. It will be shown that this statement
extends to certain pairs of unsharp observables. Implications for local
relativistic quantum theory will be discussed.


title: Robust Distributed Averaging on Networks with Adversarial Intervention

abstract:
  We study the interaction between a network designer and an adversary over a
dynamical network. The network consists of nodes performing continuous-time
distributed averaging. The goal of the network designer is to assist the nodes
reach consensus by changing the weights of a limited number of links in the
network. Meanwhile, an adversary strategically disconnects a set of links to
prevent the nodes from converging. We formulate two problems to describe this
competition where the order in which the players act is reversed in the two
problems. We utilize Pontryagin's Maximum Principle (MP) to tackle both
problems and derive the optimal strategies. Although the canonical equations
provided by the MP are intractable, we provide an alternative characterization
for the optimal strategies that highlights a connection with potential theory.
Finally, we provide a sufficient condition for the existence of a saddle-point
equilibrium (SPE) for this zero-sum game.


title: Automorphism-invariant modules satisfy the exchange property

abstract:
  Warfield proved that every injective module has the exchange property. This
was generalized by Fuchs who showed that quasi-injective modules satisfy the
exchange property. We extend this further and prove that a module invariant
under automorphisms of its injective hull satisfies the exchange property. We
also show that automorphism-invariant modules are clean and that
directly-finite automorphism-invariant modules satisfy the internal
cancellation and hence the cancellation property.


title: Importance sampling for the simulation of reinsurance losses

abstract:
  Importance sampling is a well developed method in statistics. Given a random
variable $X$, the problem of estimating its expected value $\mu$ is addressed.
The standard approach is to use the sample mean as an estimator $\bar x$. In
importance sampling, a suitable variable $L$ is introduced such that the random
variable $X/L$ has an estimator with a smaller variance than that of $\bar x$.
As a result, a smaller sample size can lead to the same estimation accuracy.
  In the simulation of reinsurance financial terms for catastrophe loss,
choosing a general variable $L$ is difficult: Even before the application of
financial terms, the loss distribution is often not modelled by a closed-form
distribution. After that, a wide range of financial terms can be applied that
makes the final distribution unpredictable. However, it is evident that the
heavy tail of the resulting net loss distribution makes the use of importance
sampling desirable. We propose an importance sampling technique using a power
function transformation on the cumulative distribution function. The benefit of
this technique is that no prior knowledge of the loss distribution is required.
It is a new technique that has not been documented in the literature. The
transformation depends on the choice of the exponent $k$. For a specific
example we investigate desirable values of $k$.


title:
Inversion of moments to retrieve joint probabilities in quantum
  sequential measurements

abstract:
  A sequence of moments encode the corresponding probability distribution.
Probing if quantum joint probability distribution can be retrieved from the
associated set of moments -- realized in the sequential measurement of a
dichotomic observable at different time intervals -- reveals a negative answer
i.e., the joint probabilities of sequential measurements do not agree with the
ones obtained by inverting the moments. This is indeed a reflection of the
non-existence of a bonafide grand joint probability distribution, consistent
with all the physical marginal probability distributions. Here we explicitly
demonstrate that given the set of moments, it is not possible to retrieve the
three-time quantum joint probability distribution resulting from quantum
sequential measurement of a single qubit dichotomic observable at three
different times. Experimental results using a nuclear magnetic resonance (NMR)
system are reported here to corroborate these theoretical observations viz.,
the incompatibility of the three-time joint probabilties with those extracted
from the moment sequence.