title: Logic Synthesis for Fault-Tolerant Quantum Computers

abstract:
  Efficient constructions for quantum logic are essential since quantum
computation is experimentally challenging. This thesis develops quantum logic
synthesis as a paradigm for reducing the resource overhead in fault-tolerant
quantum computing. The model for error correction considered here is the
surface code. After developing the theory behind general logic synthesis, the
resource costs of magic-state distillation for the $T = \exp(i \pi (I-Z)/8)$
gate are quantitatively analyzed. The resource costs for a relatively new
protocol distilling multi-qubit Fourier states are calculated for the first
time. Four different constructions of the fault-tolerant Toffoli gate,
including two which incorporate error detection, are analyzed and compared. The
techniques of logic synthesis reduce the cost of fault-tolerant quantum
computation by one to two orders of magnitude, depending on which benchmark is
used.
  Using resource analysis for $T$ gates and Toffoli gates, several proposals
for constructing arbitrary quantum gates are compared, including "Clifford+$T$"
sequences, $V$-basis sequences, phase kickback, and programmable ancilla
rotations. The application of arbitrary gates to quantum algorithms for
simulating chemistry is discussed as well. Finally, the thesis examines the
techniques which lead to efficient constructions of quantum logic, and these
observations point to even broader applications of logic synthesis.


title:
Measurement of the differential and double-differential Drell-Yan cross
  sections in proton-proton collisions at sqrt(s) = 7 TeV

abstract:
  Measurements of the differential and double-differential Drell-Yan cross
sections are presented using an integrated luminosity of 4.5 (4.8) inverse
femtobarns in the dimuon (dielectron) channel of proton-proton collision data
recorded with the CMS detector at the LHC at sqrt(s) = 7 TeV. The measured
inclusive cross section in the Z-peak region (60-120 GeV) is sigma(ell ell) =
986.4 +/- 0.6 (stat.) +/- 5.9 (exp. syst.) +/- 21.7 (th. syst.) +/- 21.7 (lum.)
pb for the combination of the dimuon and dielectron channels. Differential
cross sections d[sigma]/d[m] for the dimuon, dielectron, and combined channels
are measured in the mass range 15 to 1500 GeV and corrected to the full phase
space. Results are also presented for the measurement of the
double-differential cross section d2[sigma]/d[m]d[abs(y)] in the dimuon channel
over the mass range 20 to 1500 GeV and absolute dimuon rapidity from 0 to 2.4.
These measurements are compared to the predictions of perturbative QCD
calculations at next-to-leading and next-to-next-to-leading orders using
various sets of parton distribution functions.


title:
Robust Optimal Power Flow with Wind Integration Using Conditional
  Value-at-Risk

abstract:
  Integrating renewable energy into the power grid requires intelligent
risk-aware dispatch accounting for the stochastic availability of renewables.
Toward achieving this goal, a robust DC optimal flow problem is developed in
the present paper for power systems with a high penetration of wind energy. The
optimal dispatch is obtained as the solution to a convex program with a
suitable regularizer, which is able to mitigate the potentially high risk of
inadequate wind power. The regularizer is constructed based on the energy
transaction cost using conditional value-at-risk (CVaR). Bypassing the
prohibitive high-dimensional integral, the distribution-free sample average
approximation method is efficiently utilized for solving the resulting
optimization problem. Case studies are reported to corroborate the efficacy of
the novel model and approach tested on the IEEE 30-bus benchmark system with
real operation data from seven wind farms.


title: The domination of Saturn's low latitude ionosphere by ring `rain'

abstract:
  Saturn's ionosphere is produced when the otherwise neutral atmosphere is
exposed to a flow of energetic charged particles or solar radiation. At low
latitudes the latter should result in a weak planet-wide glow in infrared (IR),
corresponding to the planet's uniform illumination by the Sun. The observed
low-latitude ionospheric electron density is lower and the temperature higher
than predicted by models. A planet-ring magnetic connection has been previously
suggested in which an influx of water from the rings could explain the lower
than expected electron densities in Saturn's atmosphere. Here we report the
detection of a pattern of features, extending across a broad latitude band from
~25 to 60 degrees, that is superposed on the lower latitude background glow,
with peaks in emission that map along the planet's magnetic field lines to gaps
in Saturn's rings. This pattern implies the transfer of charged water products
from the ring-plane to the ionosphere, revealing the influx on a global scale,
flooding between 30 to 43% of the planet's upper-atmospheric surface. This ring
`rain' plays a fundamental role in modulating ionospheric emissions and
suppressing electron densities.


title:
Photon neutrino-production in a chiral EFT for nuclei and extrapolation
  to $E_{\nu}\sim$ GeV region

abstract:
  We carry out a series of studies on pion and photon productions in
neutrino/electron/photon--nucleus scatterings. The low energy region is
investigated by using a chiral effective field theory for nuclei. The results
for the neutral current induced photon production ($\gamma$-NCP) are then
extrapolated to neutrino energy $E_{\nu}\sim$ GeV region. By convoluting the
cross sections with MiniBooNE's beam spectrum and detection efficiency, we
estimate its $\gamma$-NCP, event number, and conclude that such photon
production can not fully explain its low energy event excess in both neutrino
and antineutrino runs.


title:
Thermodynamics of the universe bounded by the cosmological event horizon
  and dominated by the tachyon fluid

abstract:
  Our aim is to investigate the thermodynamic properties of the universe
bounded by the cosmological event horizon and dominated by the tachyon fluid.
We give two different laws of evolution of our universe. Further, we show the
first law and the generalized second law of thermodynamics (GSLT) are both
satisfied in two cases, but their properties of the thermodynamic equilibrium
are totally different. Besides, under our solutions, we find the validity of
the laws of thermodynamics is irrelevant with the parameters of the tachyon
fluid. Finally, we conclude that the universe bounded by the cosmological event
horizon and dominated by the tachyon fluid has a good thermodynamic
description. In turn, the thermodynamic description can provide a good physical
interpretation for the dynamic evolution of our universe due to the equivalence
between the first law of thermodynamics and the Friedmann equation to some
extent.


title:
Towards an Einstein-Podolsky-Rosen paradox between two macroscopic
  atomic ensembles at room temperature

abstract:
  Experiments have reported the entanglement of two spatially separated
macroscopic atomic ensembles at room temperature (Krauter et al 2011 Phys. Rev.
Lett. 107 080503; Julsgaard et al 2001 Nature 413 400). We show how an
Einstein-Podolsky-Rosen (EPR) paradox is realizable with this experiment. Our
proposed test involves violation of an inferred Heisenberg uncertainty
principle, which is a sufficient condition for an EPR paradox. This is a
stronger test of nonlocality than entanglement. Our proposal would enable the
first definitive confirmation of quantum EPR paradox correlations between two
macroscopic objects at room temperature. This is a necessary intermediate step
towards a nonlocal experiment with causal measurement separations. As well as
having fundamental significance, the realization of an atomic EPR paradox could
provide a resource for novel applications in quantum technology.


title: Scalable Visibility Color Map Construction in Spatial Databases

abstract:
  Recent advances in 3D modeling provide us with real 3D datasets to answer
queries, such as "What is the best position for a new billboard?" and "Which
hotel room has the best view?" in the presence of obstacles. These applications
require measuring and differentiating the visibility of an object (target) from
different viewpoints in a dataspace, e.g., a billboard may be seen from two
viewpoints but is readable only from the viewpoint closer to the target. In
this paper, we formulate the above problem of quantifying the visibility of
(from) a target object from (of) the surrounding area with a visibility color
map (VCM). A VCM is essentially defined as a surface color map of the space,
where each viewpoint of the space is assigned a color value that denotes the
visibility measure of the target from that viewpoint. Measuring the visibility
of a target even from a single viewpoint is an expensive operation, as we need
to consider factors such as distance, angle, and obstacles between the
viewpoint and the target. Hence, a straightforward approach to construct the
VCM that requires visibility computation for every viewpoint of the surrounding
space of the target, is prohibitively expensive in terms of both I/Os and
computation, especially for a real dataset comprising of thousands of
obstacles. We propose an efficient approach to compute the VCM based on a key
property of the human vision that eliminates the necessity of computing the
visibility for a large number of viewpoints of the space. To further reduce the
computational overhead, we propose two approximations; namely, minimum bounding
rectangle and tangential approaches with guaranteed error bounds. Our extensive
experiments demonstrate the effectiveness and efficiency of our solutions to
construct the VCM for real 2D and 3D datasets.


title: Magnetic Reconnection under Anisotropic MHD Approximation

abstract:
  We study the formation of slow-mode shocks in collisionless magnetic
reconnection by using one- and two-dimensional collisionless MHD codes based on
the double adiabatic approximation and the Landau closure model. We bridge the
gap between the Petschek-type MHD reconnection model accompanied by a pair of
slow shocks and the observational evidence of the rare occasion of in-situ slow
shock observation. Our results showed that once magnetic reconnection takes
place, a firehose-sense pressure anisotropy arises in the downstream region,
and the generated slow shocks are quite weak comparing with those in an
isotropic MHD. In spite of the weakness of the shocks, however, the resultant
reconnection rate is 10-30% higher than that in an isotropic case. This result
implies that the slow shock does not necessarily play an important role in the
energy conversion in the reconnection system, and is consistent with the
satellite observation in the Earth's magnetosphere.


title:
On total flexibility of local structures of Finsler tori without
  conjugate points

abstract:
  We show that given a point on a Finsler surface, one can always find a
neighborhood of the point and isometrically embed this neighborhood into a
Finsler torus without conjugate points.


title:
Relax but stay in control: from value to algorithms for online Markov
  decision processes

abstract:
  Online learning algorithms are designed to perform in non-stationary
environments, but generally there is no notion of a dynamic state to model
constraints on current and future actions as a function of past actions.
State-based models are common in stochastic control settings, but commonly used
frameworks such as Markov Decision Processes (MDPs) assume a known stationary
environment. In recent years, there has been a growing interest in combining
the above two frameworks and considering an MDP setting in which the cost
function is allowed to change arbitrarily after each time step. However, most
of the work in this area has been algorithmic: given a problem, one would
develop an algorithm almost from scratch. Moreover, the presence of the state
and the assumption of an arbitrarily varying environment complicate both the
theoretical analysis and the development of computationally efficient methods.
This paper describes a broad extension of the ideas proposed by Rakhlin et al.
to give a general framework for deriving algorithms in an MDP setting with
arbitrarily changing costs. This framework leads to a unifying view of existing
methods and provides a general procedure for constructing new ones. Several new
methods are presented, and one of them is shown to have important advantages
over a similar method developed from scratch via an online version of
approximate dynamic programming.


title: Quantum Search with General Nonlinearities

abstract:
  Evolution by the Gross-Pitaevskii equation, which describes Bose-Einstein
condensates under certain conditions, solves the unstructured search problem
more efficiently than does the Schr\"odinger equation, because it includes a
cubic nonlinearity, proportional to $|\psi|^2\psi$. This is not the only
nonlinearity of the form $f(|\psi|^2)\psi$ that arises in effective equations
for the evolution of real quantum physical systems, however: The cubic-quintic
nonlinear Schr\"odinger equation describes light propagation in nonlinear Kerr
media with defocusing corrections, and the logarithmic nonlinear Schr\"odinger
equation describes Bose liquids under certain conditions. Analysis of
computation with such systems yields some surprising results; for example, when
time-measurement precision is included in the resource accounting, searching a
"database" when there is a single correct answer may be easier than searching
when there are multiple correct answers. In each of these cases the nonlinear
equation is an effective approximation to a multi-particle Schr\"odinger
equation, for search by which Grover's algorithm is optimal. Thus our results
lead to quantum information-theoretic bounds on the physical resources required
for these effective nonlinear theories to hold, asymptotically.


title: Maximum Orders of Cyclic and Abelian Extendable Actions on Surfaces

abstract:
  Let $\Sigma_g (g>1)$ be a closed surface embedded in $S^3$. If a group $G$
can acts on the pair $(S^3, \Sigma_g)$, then we call such a group action on
$\Sigma_g$ extendable over $S^3$.
  In this paper we show that the maximum order of extendable cyclic group
actions is $4g+4$ when $g$ is even and $4g-4$ when $g$ is odd; the maximum
order of extendable abelian group actions is $4g+4$.
  We also give results of similar questions about extendable group actions over
handlebodies.


title: The temperature shifts of the resonances of the NV- center in diamond

abstract:
  Significant attention has been recently focused on the realization of high
precision nano-thermometry using the spin-resonance temperature shift of the
negatively charged nitrogen-vacancy (NV-) center in diamond. However, the
precise physical origins of the temperature shift is yet to be understood.
Here, the shifts of the center's optical and spin resonances are observed and a
model is developed that identifies the origin of each shift to be a combination
of thermal expansion and electron-phonon interactions. Our results provide new
insight into the center's vibronic properties and reveal implications for NV-
thermometry.


title: X-ray observations and the search for Fermi-LAT gamma-ray pulsars

abstract:
  The Large Area Telescope (LAT) on Fermi has detected ~150 gamma-ray pulsars,
about a third of which were discovered in blind searches of the $\gamma$-ray
data. Because the angular resolution of the LAT is relatively poor and blind
searches for pulsars (especially millisecond pulsars, MSPs) are very sensitive
to an error in the position, one must typically scan large numbers of
locations. Identifying plausible X-ray counterparts of a putative pulsar
drastically reduces the number of trials, thus improving the sensitivity of
pulsar blind searches with the LAT. I discuss our ongoing program of Swift,
XMM-Newton, and Chandra observations of LAT unassociated sources in the context
of our blind searches for gamma-ray pulsars.


title:
Optimized Markov Chain Monte Carlo for Signal Detection in MIMO Systems:
  an Analysis of Stationary Distribution and Mixing Time

abstract:
  In this paper we introduce an optimized Markov Chain Monte Carlo (MCMC)
technique for solving the integer least-squares (ILS) problems, which include
Maximum Likelihood (ML) detection in Multiple-Input Multiple-Output (MIMO)
systems. Two factors contribute to the speed of finding the optimal solution by
the MCMC detector: the probability of the optimal solution in the stationary
distribution, and the mixing time of the MCMC detector. Firstly, we compute the
optimal value of the "temperature" parameter, in the sense that the temperature
has the desirable property that once the Markov chain has mixed to its
stationary distribution, there is polynomially small probability
($1/\mbox{poly}(N)$, instead of exponentially small) of encountering the
optimal solution. This temperature is shown to be at most
$O(\sqrt{SNR}/\ln(N))$, where $SNR$ is the signal-to-noise ratio, and $N$ is
the problem dimension. Secondly, we study the mixing time of the underlying
Markov chain of the proposed MCMC detector. We find that, the mixing time of
MCMC is closely related to whether there is a local minimum in the lattice
structures of ILS problems. For some lattices without local minima, the mixing
time of the Markov chain is independent of $SNR$, and grows polynomially in the
problem dimension; for lattices with local minima, the mixing time grows
unboundedly as $SNR$ grows, when the temperature is set, as in conventional
wisdom, to be the standard deviation of noises. Our results suggest that, to
ensure fast mixing for a fixed dimension $N$, the temperature for MCMC should
instead be set as $\Omega(\sqrt{SNR})$ in general. Simulation results show that
the optimized MCMC detector efficiently achieves approximately ML detection in
MIMO systems having a huge number of transmit and receive dimensions.


title: Left invariant Randers metrics on the 3-dimensional Heisenberg group

abstract:
  In the previous paper [MR2430243] we computed some geometric quantities such
as curvature and flag curvature for a general left invariant Finsler metric on
a two-step nilpotent group. In the present paper we give a more complete
description of the Chern--Rund connection defined by a left invariant Randers
metric on the 3 dimensional Heisenberg group.


title: Groups with exactly two conjugacy classes

abstract:
  Using the concept of algebraically closed groups, we prove that there is a
countable torsion free group with exactly two conjugacy classes.


title:
Laplacian and signless Laplacian spectral radii of graphs with fixed
  domination number

abstract:
  In this paper, we determine the maximal Laplacian and signless Laplacian
spectral radii for graphs with fixed number of vertices and domination number,
and characterize the extremal graphs respectively.


title:
Using Binary Pulsars to Test Lorentz Symmetry in the Gravitational
  Sector

abstract:
  I review some of the major developments in the theoretical background and
experimental uses of binary pulsars to explore local Lorentz invariance in the
gravitational sector and its possible violation.


title:
Angle-resolved photoemission spectroscopy observation of anomalous
  electronic states in EuFe$_2$As$_{2-x}$P$_x$

abstract:
  We used angle-resolved photoemission spectroscopy to investigate the
electronic structure of EuFe$_2$As$_2$, EuFe$_2$As$_{1.4}$P$_{0.6}$ and
EuFe$_2$P$_2$. We observed doubled core level peaks associated to the pnictide
atoms, which are related to a surface state. Nevertheless, strong electronic
dispersion along the $c$ axis, especially pronounced in EuFe$_2$P$_2$, is
observed for at less one band, thus indicated that the Fe states, albeit
probably affected at the surface, do not form pure two-dimensional surface
states. However, this latter material shows reduced spectral weight near the
Fermi level as compared to EuFe$_2$As$_2$ and EuFe$_2$As$_{1.4}$P$_{0.6}$. An
anomalous jump is also found in the electronic states associated with the
Eu$^{2+}$ $f$ states in EuFe$_2$P$_2$.


title:
On the Degrees of Freedom of Asymmetric MIMO Interference Broadcast
  Channels

abstract:
  In this paper, we study the degrees of freedom (DoF) of the asymmetric
multi-input-multi-output interference broadcast channel (MIMO-IBC). By
introducing a notion of connection pattern chain, we generalize the genie chain
proposed in [11] to derive and prove the necessary condition of IA feasibility
for asymmetric MIMO-IBC, which is denoted as irreducible condition. It is
necessary for both linear interference alignment (IA) and asymptotic IA
feasibility in MIMO-IBC with arbitrary configurations. In a special class of
asymmetric two-cell MIMOIBC, the irreducible condition is proved to be the
sufficient and necessary condition for asymptotic IA feasibility, while the
combination of proper condition and irreducible condition is proved to the
sufficient and necessary condition for linear IA feasibility. From these
conditions, we derive the information theoretic maximal DoF per user and the
maximal DoF per user achieved by linear IA, and these DoFs are also the DoF per
user upper-bounds of asymmetric G-cell MIMO-IBC with asymptotic IA and linear
IA, respectively.


title:
A random flight process associated to a Lorentz gas with variable
  density in a gravitational field

abstract:
  We investigate the random flight process that arises as the Boltzmann-Grad
limit of a random scatterer Lorentz gas with variable scatterer density in a
gravitational field. For power function densities we show how the parameters of
the model determine recurrence or transience of the vertical component of the
trajectory. Finally, our methods show that, with appropriate scaling of space,
time and the density of obstacles, the trajectory of the particle converges to
a diffusion with explicitly given parameters.


title: A note on skew spectrum of graphs

abstract:
  We give some properties of skew spectrum of a graph, especially, we answer
negatively a problem concerning the skew characteristic polynomial and matching
polynomial in [M. Cavers et al., Skew-adjacency matrices of graphs, Linear
Algebra Appl. 436 (2012)
  4512--4529].


title:
On Heegaard splittings of knot exteriors with tunnel number
  degenerations

abstract:
  Let $K_1, K_2$ be two knots with $t(K_1)+t(K_2)>2$ and $t(K_1 # K_2)=2$.
Then, in the present paper, we will show that any genus three Heegaard
splittings of $E(K_1 # K_2)$ is strongly irreducible and that $E(K_1 # K_2)$
has at most four genus three Heegaard splittings up to homeomorphism. Moreover,
we will give a complete classification of those four genus three Heegaard
splittings and show unknotting tunnel systems of knots $K_1 # K_2$
corresponding to those Heegaard splittings.


title: The Twenty-Five Year Lick Planet Search

abstract:
  The Lick planet search program began in 1987 when the first spectrum of
$\tau$ Ceti was taken with an iodine cell and the Hamilton Spectrograph.
Upgrades to the instrument improved the Doppler precision from about 10 m/s in
1992 to about 3 m/s in 1995. The project detected dozens of exoplanets with
orbital periods ranging from a few days to several years. The Lick survey
identified the first planet in an eccentric orbit (70 Virginis) and the first
multi-planet system around a normal main sequence star (Upsilon Andromedae).
These discoveries advanced our understanding of planet formation and orbital
migration. Data from this project helped to quantify a correlation between host
star metallicity and the occurrence rate of gas giant planets. The program also
served as a test bed for innovation with testing of a tip-tilt system at the
coud{\'e} focus and fiber scrambler designs to stabilize illumination of the
spectrometer optics. The Lick planet search with the Hamilton spectrograph
effectively ended when a heater malfunction compromised the integrity of the
iodine cell. Here, we present more than 14,000 velocities for 386 stars that
were surveyed between 1987 and 2011.


title:
Single Crystalline InGaAs Nanopillar Grown on Polysilicon with
  Dimensions beyond Substrate Grain Size Limit

abstract:
  Monolithic integration of III-V optoelectronic devices with materials for
various functionalities inexpensively is always desirable. Polysilicon
(poly-Si) is an ideal platform because it is dopable and semi-conducting and
can be deposited and patterned easily on a wide range of low cost substrates.
However, the lack of crystalline coherency in poly-Si poses an immense
challenge for high-quality epitaxial growth. In this work, we demonstrate, for
the first time, direct growth of micron-sized InGaAs/GaAs nanopillars on
polysilicon. Transmission electron microscopy shows that the micron-sized
pillars are single-crystalline and single Wurzite-phase, far exceeding the
substrate crystal grain size ~100nm. The high quality growth is enabled by the
unique tapering geometry at the base of the nanostructure, which reduces the
effective InGaAs/Si contact area to < 40 nm in diameter. The small footprint
not only reduces stress due to lattice mismatch but also prevents the
nanopillar from nucleating on multiple Si crystal grains. This relaxes the
grain size requirement for poly-Si, potentially reducing the cost for poly-Si
deposition. Lasing is achieved in the as-grown pillars under optical pumping,
attesting their excellent crystalline and optical quality. These promising
results open up a pathway for low-cost synergy of optoelectronics with other
technologies such as CMOS integrated circuits, sensing, nanofluidics, thin film
transistor display, photovoltaics, etc.


title: Magnetic structure and spin excitations in BaMn2Bi2

abstract:
  We present a single crystal neutron scattering study of BaMn2Bi2, a recently
synthesized material with the same ThCr2Si2-type structure found in several
Fe-based unconventional superconducting materials. We show long range magnetic
order, in the form of a G-type antiferromagnetic structure, to exist up to 390
K with an indication of a structural transition at 100 K. Utilizing inelastic
neutron scattering we observe a spin-gap of 16meV, with spin-waves extending up
to 55 meV. We find these magnetic excitations to be well fit to a J1-J2-Jc
Heisenberg model and present values for the exchange interactions. The spin
wave spectrum appears to be unchanged by the 100 K structural phase transition.


title: Yangians, quantum loop algebras and abelian difference equations

abstract:
  Let g be a complex, semisimple Lie algebra, and Y_h(g) and U_q(Lg) the
Yangian and quantum loop algebra of g. Assuming that h is not a rational number
and that q=exp(i \pi h), we construct an equivalence between the
finite-dimensional representations of U_q(Lg) and an explicit subcategory of
those of Y_h(g) defined by choosing a branch of the logarithm. This equivalence
is governed by the monodromy of the abelian additive difference equations
defined by the commuting fields of Y_h(g). Our results are compatible with
q-characters, and apply more generally to a symmetrisable Kac-Moody algebra g,
in particular to affine Yangians and quantum toroidal algebras. In this
generality, they yield an equivalence between the representations of Y_h(g) and
U_q(Lg) whose restriction to g and U_q(g) respectively are integrable and in
category O.


title: Update on $B_K$ and $\varepsilon_K$ with staggered quarks

abstract:
  We update our results for $B_K$ obtained using HYP-smeared staggered valence
quarks on the MILC asqtad lattices. In the last year, we have added 5 new
measurments on the fine ($a\approx 0.09\;$fm) ensembles, and 2 new measurements
on the superfine ($a\approx 0.06\;$fm) ensembles. These allow a simultaneous
extrapolation in $a^2$ and sea quark masses, reducing the corresponding
systematic error significantly. Our updated result is $\hat{B}_K = 0.738 \pm
0.005 (\text{stat}) \pm 0.034 (\text{sys})$.


title:
High Dimensional Robust M-Estimation: Asymptotic Variance via
  Approximate Message Passing

abstract:
  In a recent article (Proc. Natl. Acad. Sci., 110(36), 14557-14562), El Karoui
et al. study the distribution of robust regression estimators in the regime in
which the number of parameters p is of the same order as the number of samples
n. Using numerical simulations and `highly plausible' heuristic arguments, they
unveil a striking new phenomenon. Namely, the regression coefficients contain
an extra Gaussian noise component that is not explained by classical concepts
such as the Fisher information matrix. We show here that that this phenomenon
can be characterized rigorously techniques that were developed by the authors
to analyze the Lasso estimator under high-dimensional asymptotics. We introduce
an approximate message passing (AMP) algorithm to compute M-estimators and
deploy state evolution to evaluate the operating characteristics of AMP and so
also M-estimates. Our analysis clarifies that the `extra Gaussian noise'
encountered in this problem is fundamentally similar to phenomena already
studied for regularized least squares in the setting n<p.


title: Rank and fooling set size

abstract:
  Say that A is a Hadamard factorization of the identity I_n of size n if the
entrywise product of A and the transpose of A is I_n. It can be easily seen
that the rank of any Hadamard factorization of the identity must be at least
sqrt{n}. Dietzfelbinger et al. raised the question if this bound can be
achieved, and showed a boolean Hadamard factorization of the identity of rank
n^{0.792}. More recently, Klauck and Wolf gave a construction of Hadamard
factorizations of the identity of rank n^{0.613}. Over finite fields, Friesen
and Theis resolved the question, showing for a prime p and r=p^t+1 a Hadamard
factorization of the identity A of size r(r-1)+1 and rank r over F_p.
  Here we resolve the question for fields of zero characteristic, up to a
constant factor, giving a construction of Hadamard factorizations of the
identity of rank r and size (r+1)r/2. The matrices in our construction are
blockwise Toeplitz, and have entries whose magnitudes are binomial
coefficients.


title: Anisotropic uniaxial pressure response of the Mott insulator Ca2RuO4

abstract:
  We have investigated the in-plane uniaxial pressure effect on the
antiferromagnetic Mott insulator Ca2RuO4 from resistivity and magnetization
measurements. We succeeded in inducing the ferromagnetic metallic phase at
lower critical pressure than by hydrostatic pressure, indicating that the
flattening distortion of the RuO6 octahedra is more easily released under
in-plane uniaxial pressure. We also found a striking in-plane anisotropy in the
pressure responses of various magnetic phases: Although the magnetization
increases monotonically with pressure diagonal to the orthorhombic principal
axes, the magnetization exhibits peculiar dependence on pressure along the
in-plane orthorhombic principal axes. This peculiar dependence can be explained
by a qualitative difference between the uniaxial pressure effects along the
orthorhombic a and b axes, as well as by the presence of twin domain
structures.


title:
Electromagnetically induced transparency and Autler-Townes splitting in
  superconducting flux quantum circuits

abstract:
  We study the microwave absorption of a driven three-level quantum system,
which is realized by a superconducting flux quantum circuit (SFQC), with a
magnetic driving field applied to the two upper levels. The interaction between
the three-level system and its environment is studied within the Born-Markov
approximation, and we take into account the effects of the driving field on the
damping rates of the three-level system. We study the linear response of the
driven three-level SFQC to a weak probe field. The linear magnetic
susceptibility of the SFQC can be changed by both the driving field and the
bias magnetic flux. When the bias magnetic flux is at the optimal point, the
transition from the ground state to the second excited state is forbidden and
the three-level SFQC has a ladder-type transition. Thus, the SFQC responds to
the probe field like natural atoms with ladder-type transitions. However, when
the bias magnetic flux deviates from the optimal point, the three-level SFQC
has a cyclic transition, thus it responds to the probe field like a combination
of natural atoms with ladder-type transitions and natural atoms with
$\Lambda$-type transitions. In particular, we provide detailed discussions on
the conditions for realizing electromagnetically induced transparency and
Autler-Townes splitting in three-level SFQCs.


title:
Distributed Estimation of a Parametric Field: Algorithms and Performance
  Analysis

abstract:
  This paper presents a distributed estimator for a deterministic parametric
physical field sensed by a homogeneous sensor network and develops a new
transformed expression for the Cramer-Rao lower bound (CRLB) on the variance of
distributed estimates. The proposed transformation reduces a multidimensional
integral representation of the CRLB to an expression involving an infinite sum.
Stochastic models used in this paper assume additive noise in both the
observation and transmission channels. Two cases of data transmission are
considered. The first case assumes a linear analog modulation of raw
observations prior to their transmission to a fusion center. In the second
case, each sensor quantizes its observation to $M$ levels, and the quantized
data are communicated to a fusion center. In both cases, parallel additive
white Gaussian channels are assumed. The paper develops an iterative
expectation-maximization (EM) algorithm to estimate unknown parameters of a
parametric field, and its linearized version is adopted for numerical analysis.
The performance of the developed numerical solution is compared to the
performance of a simple iterative approach based on Newton's approximation.
While the developed solution has a higher complexity than Newton's solution, it
is more robust with respect to the choice of initial parameters and has a
better estimation accuracy. Numerical examples are provided for the case of a
field modeled as a Gaussian bell, and illustrate the advantages of using the
transformed expression for the CRLB. However, the distributed estimator and the
derived CRLB are general and can be applied to any parametric field. The
dependence of the mean-square error (MSE) on the number of quantization levels,
the number of sensors in the network and the SNR of the observation and
transmission channels are analyzed. The variance of the estimates is compared
to the derived CRLB.


title:
Local correlation effects on the s+-- and s++-wave superconductivities
  mediated by magnetic and orbital fluctuations in the 5-orbital Hubbard model
  for iron pnictides

abstract:
  We investigate the electronic state and the superconductivity in the
5-orbital Hubbard model for iron pnictides by using the dynamical mean-field
theory in conjunction with the Eliashberg equation. The renormalization factor
exhibits significant orbital dependence resulting in the large change in the
band dispersion as observed in recent ARPES experiments. The critical
interactions towards the magnetic, orbital and superconducting instabilities
are suppressed as compared with those from the random phase approximation (RPA)
due to local correlation effects. Remarkably, the s++-pairing phase due to the
orbital fluctuation is largely expanded relative to the RPA result, while the
s+--pairing phase due to the magnetic fluctuation is reduced.


title: Individualism: The legacy of great physicists

abstract:
  A recent high school graduate addresses the salient question: Should
individualism or collectivism be encouraged in physics students? (Physics
Today, Points of View, October 2013)


title:
Metal-insulator transition and superconductivity in the two-orbital
  Hubbard-Holstein model for iron-based superconductors

abstract:
  We investigate a two-orbital model for iron-based superconductors to
elucidate the effect of interplay between electron correlation and Jahn-Teller
electron-phonon coupling by using the dynamical mean-field theory combined with
the exact diagonalization method. When the intra- and inter-orbital Coulomb
interactions, $U$ and $U'$, increase with $U=U'$, both the local spin and
orbital susceptibilities, $\chi_{s}$ and $\chi_{o}$, increase with
$\chi_{s}=\chi_{o}$ in the absence of the Hund's rule coupling $J$ and the
electron-phonon coupling $g$. In the presence of $J$ and $g$, there are
distinct two regimes: for $J \stackrel{>}{_\sim} 2g^2/\omega_0$ with the phonon
frequency $\omega_0$, $\chi_{s}$ is enhanced relative to $\chi_{o}$ and shows a
divergence at $J=J_c$ above which the system becomes Mott insulator, while for
$J \stackrel{<}{_\sim} 2g^2/\omega_0$, $\chi_{o}$ is enhanced relative to
$\chi_{s}$ and shows a divergence at $g=g_c$ above which the system becomes
bipolaronic insulator. In the former regime, the superconductivity is mediated
by antiferromagnetic fluctuations enhanced due to Fermi-surface nesting and is
found to be largely dependent on carrier doping. On the other hand, in the
latter regime, the superconductivity is mediated by ferro-orbital fluctuations
and is observed for wide doping region including heavily doped case without the
Fermi-surface nesting.


title: HD 285507b: An Eccentric Hot Jupiter in the Hyades Open Cluster

abstract:
  We report the discovery of the first hot Jupiter in the Hyades open cluster.
HD 285507b orbits a V=10.47 K4.5V dwarf ($M_* = 0.734 M_\odot$; $R_* = 0.656
R_\odot$) in a slightly eccentric ($e = 0.086^{+0.018}_{-0.019}$) orbit with a
period of $6.0881^{+0.0019}_{-0.0018}$ days. The induced stellar radial
velocity corresponds to a minimum companion mass of $M_{\rm p} \sin{i} = 0.917
\pm 0.033 M_{\rm Jup}$. Line bisector spans and stellar activity measures show
no correlation with orbital phase, and the radial velocity amplitude is
independent of wavelength, supporting the conclusion that the variations are
caused by a planetary companion. Follow-up photometry indicates with high
confidence that the planet does not transit. HD 285507b joins a small but
growing list of planets in open clusters, and its existence lends support to a
planet formation scenario in which a high stellar space density does not
inhibit giant planet formation and migration. We calculate the circularization
timescale for HD 285507b to be larger than the age of the Hyades, which may
indicate that this planet's non-zero eccentricity is the result of migration
via interactions with a third body. We also demonstrate a significant
difference between the eccentricity distributions of hot Jupiters that have had
time to tidally circularize and those that have not, which we interpret as
evidence against Type II migration in the final stages of hot Jupiter
formation. Finally, the dependence of the circularization timescale on the
planetary tidal quality factor, $Q_{\rm p}$, allows us to constrain the average
value for hot Jupiters to be $\log{Q_{\rm p}} = 6.14^{+0.41}_{-0.25}$.


title:
The symplectic mapping class group of $\CC P^2 n{\bar{\CC P^2}}$ with
  $n\leq4$

abstract:
  In this paper we prove that the Torelli part of the symplectomorphism groups
of the $n$-point ($n\leq 4$) blow-ups of the projective plane is trivial.
Consequently, we determine the symplectic mapping class group. It is generated
by reflections on $K_{\omega}- $spherical class with zero $\omega$ area.


title:
Polarization-rotation resonances with subnatural widths using a control
  laser

abstract:
  We demonstrate extremely narrow resonances for polarization rotation in an
atomic vapor. The resonances are created using a strong control laser on the
same transition, which polarizes the atoms due to optical pumping among the
magnetic sublevels. As the power in the control laser is increased,
successively higher-order nested polarization rotation resonances are created,
with progressively narrower linewidths. We study these resonances in the $D_2$
line of Rb in a room-temperature vapor cell, and demonstrate a width of $0.14
\, \Gamma$ for the third-order rotation. The explanation based on a simplified
$\Lambda$V-type level structure is borne out by a density-matrix analysis of
the system. The dispersive lineshape and subnatural width of the resonance
lends itself naturally to applications such as laser locking to atomic
transitions and precision measurements.


title: On the quantum Horn problem

abstract:
  Let $K$ be a compact, connected, simply-connected simple Lie group. Given two
conjugacy classes $\Orb_1$ and $\Orb_2$ in $K$, we consider the multiplicative
Horn question: What conjugacy classes are contained in $\Orb_1\cdot\Orb_2$? It
is known that answering this question remains to describe a convex polytope
$\poly_K$. In 2003, Teleman-Woodward gave a complete list of inequalities for
$\poly_K$. Their list contains redundant inequalities. In this paper, we
describe $\poly_K$ by a smaller list of inequalities.


title: Large deviations for a damped telegraph process

abstract:
  In this paper we consider a slight generalization of the damped telegraph
process in Di Crescenzo and Martinucci (2010). We prove a large deviation
principle for this process and an asymptotic result for its level crossing
probabilities (as the level goes to infinity). Finally we compare our results
with the analogous well-known results for the standard telegraph process.


title:
Two-point function for the Maxwell field in flat Robertson-Walker
  spacetimes

abstract:
  We obtain an explicit two-point function for the Maxwell field in flat
Roberson-Walker spaces, thanks to a new gauge condition which takes the scale
factor into account and assume a simple form. The two-point function is found
to have the short distance Hadamard behavior.


title:
The problem of space in the light of relativity: the views of H. Weyl
  and E. Cartan

abstract:
  Starting from a short review of the "classical" space problem in the sense of
the 19th century (Helmholtz -- Lie -- Klein) it is discussed how the challenges
posed by special and general relativity to the classical analysis were taken up
by Hermann Weyl and Elie Cartan. Both mathematicians reconsidered the space
problem from the point of view of transformations operating in the
infinitesimal neighbourhoods of a manifold (spacetime). In a short outlook we
survey further developments in mathematics and physics of the second half of
the 20th century, in which core ideas of Weyl's and/or Cartan's analysis of the
space problem were further investigated (mathematics) or incorporated into
basic theories (physics).


title: PT sym\'etrie et puits de potentiel

abstract:
  In this work we consider PT-symmetric perturbations of a self-adjoint
semi-classical Schr\"odinger operator on the real axis in the case of a simple
potential well. We assume that the potential is analytic and show that the
eigenvalues remain real under the perturbation.
  Dans ce travail, on consid\`ere des perturbations PT -sym\'etriques d'un
op\'erateur de Schr\"odinger semi-classique auto-adjoint sur la droite r\'eel
dans le cas d'un puits de potentiel simple. On suppose que le potentiel soit
analytique et on montre que les valeurs propres restent r\'eelles sous la
perturbation.


title:
Robustness of multiparticle entanglement: specific entanglement classes
  and random states

abstract:
  We investigate the robustness of genuine multiparticle entanglement under
decoherence. We consider different kinds of entangled three- and four-qubit
states as well as random pure states. For amplitude damping noise, we find that
the W-type states are most robust, while other states are not more robust than
generic states. For phase damping noise the GHZ state is the most robust state,
and for depolarizing noise several states are significantly more robust than
random states.


title: Chern character for matrix factorizations via Chern-Weil

abstract:
  Given a matrix factorization, we use the Atiyah class to give an algebraic
Chern-Weil type construction to its Chern character; this allows us to realize
the Chern character in an explicit way. It also generalizes the existing result
to any smooth $k$-algebra $Q$ ($k$ a commutative ring containing $\mathbb{Q}$)
and any $f\in Q$, which agrees with a recent result of Platt. We also study
some basic properties of the Chern character.


title:
Temperature dependent weak value of dwell time for a two state particle
  tunneling through a thermal magnetic barrier

abstract:
  Dwell time for a two state particle tunneling through a noisy thermal
magnetic barrier has been calculated by studying the time evolution of the
system. The effect of temperature has been included by averaging over the
environmental magnetic modes. The time scale has been calculated in the
framework of weak measurement. The dwell time initially increases with the rise
of temperature and finally saturates. The increment of dwell time can be
explained by the phenomena of quantum memory loss caused by efficient energy
exchange with the environmental modes. The saturation region at higher
temperature corresponds to the process of thermal hopping of the barrier.


title:
Invariant envelopes of holomorphy in the complexification of a Hermitian
  symmetric space

abstract:
  In this paper we investigate invariant domains in $\, \Xi^+$, a distinguished
$\,G$-invariant, Stein domain in the complexification of an irreducible
Hermitian symmetric space $\,G/K$. The domain $\,\Xi^+$, recently introduced by
Kr\"otz and Opdam, contains the crown domain $\,\Xi\,$ and it is maximal with
respect to properness of the $\,G$-action. In the tube case, it also contains
$\,S^+$, an invariant Stein domain arising from the compactly causal structure
of a symmetric orbit in the boundary of $\,\Xi$. We prove that the envelope of
holomorphy of an invariant domain in $\,\Xi^+$, which is contained neither in
$\,\Xi\,$ nor in $\,S^+$, is univalent and coincides with $\,\Xi^+$. This fact,
together with known results concerning $\,\Xi\,$ and $\,S^+$, proves the
univalence of the envelope of holomorphy of an arbitrary invariant domain in
$\,\Xi^+\,$ and completes the classification of invariant Stein domains
therein.


title: Diffraction as a critical ingredient in soft scattering

abstract:
  The roll of diffraction in the formulation of soft scattering is investigated
aiming to assess the resent SD TOTEM results.


title: Thorium isomer for radiative emission of neutrino pair

abstract:
  It is proposed to use the isomer ionic ground state $^{229m}$Th$^{4+}$
embedded in transparent crystals for precision determination of unknown
neutrino parameters. Isolation from solid environment of the proposed nuclear
process, along with available experimental techniques of atomic physics, has a
great potentiality for further study.


title:
I$_{2}$ molecule for neutrino mass spectroscopy: ab initio calculation
  of spectral rate

abstract:
  It has recently been argued that atoms and molecules may become good targets
of determining neutrino parameters still undetermined, if atomic/molecular
process is enhanced by a new kind of coherence. We compute photon energy
spectrum rate arising from coherent radiative neutrino pair emission processes
of metastable excited states of I$_2$ and its iso-valent molecules, $|Av
\rangle \rightarrow |Xv' \rangle + \gamma + \nu_i\nu_j$ and $|A'v \rangle
\rightarrow |Xv' \rangle + \gamma + \nu_i\nu_j$ with $\gamma$ an IR photon and
$\nu_{i(j)}$ $i(j)-$th neutrino mass eigenstates, and show how fundamental
neutrino parameters may be determined. Energies of electronically excited
states of I$_2$, including the effect of spin-orbit couplings were calculated
by the multiconfigurational second order perturbation (CASPT2) method.
Summation over many vibrational levels of intermediate states is fully
incorporated. Unlike atomic candidate of a much larger energy difference such
as Xe, I$_2$ transitions from a vibrational level $A(v=0)$ to $X(v' = 24)$ give
an opportunity of determination of the mass type (Majorana vs Dirac
distinction) and determination of Majorana CPV (charge-conjugation parity
violating) phases, although the rate is much smaller.


title: Future Reactor Experiments

abstract:
  The measurement of the neutrino mixing angle $\theta_{13}$ opens a gateway
for the next generation experiments to measure the neutrino mass hierarchy and
the leptonic CP-violating phase. Future reactor experiments will focus on mass
hierarchy determination and the precision measurement of mixing parameters.
Mass hierarchy can be determined from the disappearance of reactor electron
antineutrinos based on the interference effect of two separated oscillation
modes. Relative and absolute measurement techniques have been explored. A
proposed experiment JUNO, with a 20 kton liquid scintillator detector of
$3%/$$\sqrt{E(MeV)}$ energy resolution, $\sim$ 53 km far from reactors of
$\sim$ 36 GW total thermal power, can reach to a sensitivity of
$\Delta\chi^{2}>16$ considering the spread of reactor cores and uncertainties
of the detector response. Three of mixing parameters are expected to be
measured to better than 1% precision. There are multiple detector options for
JUNO under investigation. The technical challenges are new type of PMTs with
high efficiency and highly transparent liquid scintillator. Funding has been
approved from Chinese Academy of Sciences. A similar proposal was from Korea
known as RENO-50. Both of them are going to start data taking around 2020.


title: The Luk\'{a}cs--Olkin--Rubin theorem on symmetric cones

abstract:
  In this paper we prove a Luk\'{a}cs type characterization theorem of the
Wishart distribution on Euclidean simple Jordan algebras under weak regularity
assumptions (e.g. measurability) on the densities.


title:
Spin polarization, dephasing and photoinduced spin diffusion in
  (110)-grown two-dimensional electron systems

abstract:
  We study the optically induced spin polarization, spin dephasing and
diffusion in several high-mobility two-dimensional electron systems, which are
embedded in GaAs quantum wells grown on (110)-oriented substrates. The
experimental techniques comprise a two-beam magneto-optical spectroscopy system
and polarization-resolved photoluminescence. Under weak excitation conditions
at liquid-helium temperatures, we observe spin lifetimes above 100 ns in one of
our samples, which are reduced with increasing excitation density due to
additional, hole-mediated, spin dephasing. The spin dynamic is strongly
influenced by the carrier density and the ionization of remote donors, which
can be controlled by temperature and above-barrier illumination. The absolute
value of the average electron spin polarization in the samples is directly
observable in the circular polarization of photoluminescence collected under
circularly polarized excitation and reaches values of about 5 percent. Spin
diffusion is studied by varying the distance between pump and probe beams in
micro-spectroscopy experiments. We observe diffusion lengths above 100 $\mu$m
and, at high excitation intensity, a nonmonotonic dependence of the spin
polarization on the pump-probe distance.


title:
Excitable human dynamics driven by extrinsic events in massive
  communities

abstract:
  Using empirical data from a social media site (Twitter) and on trading
volumes of financial securities, we analyze the correlated human activity in
massive social organizations. The activity, typically excited by real-world
events and measured by the occurrence rate of international brand names and
trading volumes, is characterized by intermittent fluctuations with bursts of
high activity separated by quiescent periods. These fluctuations are broadly
distributed with an inverse cubic tail and have long-range temporal
correlations with a $1/f$ power spectrum. We describe the activity by a
stochastic point process and derive the distribution of activity levels from
the corresponding stochastic differential equation. The distribution and the
corresponding power spectrum are fully consistent with the empirical
observations.


title:
Kazhdan-Lusztig coefficients for the lowest two-sided cell of type
  $\tilde{G_{2}}$

abstract:
  This paper studies the Kazhdan-Lusztig coefficients $\mu(u,w)$ of the
Kazhdan-Lusztig polynomials $P_{u,w}$ for the lowest cell ${c_{0}}$ of an
affine Weyl group of type $\widetilde{G_{2}}$ and gives an estimation
$\mu(u,w)\leqslant 3$ for $u,w\in c_{0}$.


title:
Electronic Structure Reconstruction across the Antiferromagnetic
  Transition in TaFe$_{1.23}$Te$_3$ Spin Ladder

abstract:
  With angle-resolved photoemission spectroscopy, we studied the electronic
structure of TaFe$_{1.23}$Te$_3$, which is a two-leg spin ladder compound with
a novel antiferromagnetic ground state. Quasi-two-dimensional Fermi surface is
observed, indicating sizable inter-ladder hopping, which would facilitate the
in-plane ferromagnetic ordering through double exchange interactions. Moreover,
an energy gap is not observed at the Fermi surface in the antiferromagnetic
state. Instead, the shifts of various bands have been observed. Combining these
observations with density-functional-theory calculations, we propose that the
large scale reconstruction of the electronic structure, caused by the
interactions between the coexisting itinerant electrons and local moments, is
most likely the driving force behind the magnetic transition.
TaFe$_{1.23}$Te$_3$ thus provides a simpler system that contains similar
ingredients as the parent compounds of iron-based superconductors, which yet
could be readily modeled and understood.


title: Wave turbulence in the two-layer ocean model

abstract:
  This paper looks at the two-layer ocean model from a wave turbulence
perspective. A symmetric form of the two-layer kinetic equation for Rossby
waves is derived using canonical variables, allowing the turbulent cascade of
energy between the barotropic and baroclinic modes to be studied. It turns out
that energy is transferred via local triad interactions from the large-scale
baroclinic modes to the baroclinic and barotropic modes at the Rossby
deformation scale. From there it is then transferred to the large-scale
barotropic modes via a nonlocal inverse transfer. Using scale separation a sys-
tem of coupled equations were obtained for the small-scale baroclinic component
and the large-scale barotropic component. Since the total energy of the
small-scale component is not conserved, but the total barotropic plus
baroclinic energy is conserved, the baroclinic energy loss at small scales will
be compensated by the growth of the barotropic energy at large scales. It is
found that this transfer is mostly anisotropic and mostly to the zonal
component.


title:
Maximal Rabi frequency of an electrically driven spin in a disordered
  magnetic field

abstract:
  We present a theoretical study of the spin dynamics of a single electron
confined in a quantum dot. Spin dynamics is induced by the interplay of
electrical driving and the presence of a spatially disordered magnetic field,
the latter being transverse to a homogeneous magnetic field. We focus on the
case of strong driving, i.e., when the oscillation amplitude $A$ of the
electron's wave packet is comparable to the quantum dot length $L$. We show
that electrically driven spin resonance can be induced in this system by
subharmonic driving, i.e., if the excitation frequency is an integer fraction
(1/2, 1/3, etc) of the Larmor frequency. At strong driving we find that (i) the
Rabi frequencies at the subharmonic resonances are comparable to the Rabi
frequency at the fundamental resonance, and (ii) at each subharmonic resonance,
the Rabi frequency can be maximized by setting the drive strength to an
optimal, finite value. Our simple model is applied to describe electrical
control of a spin-valley qubit in a weakly disordered carbon nanotube.


title: Order isomorphisms on function spaces

abstract:
  The classical theorems of Banach and Stone, Gelfand and Kolmogorov, and
Kaplansky show that a compact Hausdorff space $X$ is uniquely determined by the
linear isometric structure, the algebraic structure, and the lattice structure,
respectively, of the space $C(X)$. In this paper, it is shown that for rather
general subspaces $A(X)$ and $A(Y)$ of $C(X)$ and $C(Y)$ respectively, any
linear bijection $T: A(X) \to A(Y)$ such that $f \geq 0$ if and only if $Tf
\geq 0$ gives rise to a homeomorphism $h: X \to Y$ with which $T$ can be
represented as a weighted composition operator. The three classical results
mentioned above can be derived as corollaries. Generalizations to noncompact
spaces and other function spaces such as spaces of uniformly continuous
functions, Lipschitz functions and differentiable functions are presented.


title: Ideals of operators on $(\oplus \ell^\infty(n))_{\ell^1}$

abstract:
  The unique maximal ideal in the Banach algebra $L(E)$, $E = (\oplus
\ell^\infty(n))_{\ell^1}$, is identified. The proof relies on techniques
developed by Laustsen, Loy and Read and a dichotomy result for operators
mapping into $L^1$ due to Laustsen, Odell, Schlumprecht and Zs\'{a}k.


title:
Determinants of a Successful Migration to Cloud Computing in Iranian
  Telecommunication Industry

abstract:
  Although the research support for Cloud Computing (CC) is still developing,
the concept of this paper has provided comprehensive frameworks for a
successful migration to cloud computing (SMCC) in telecommunication industry in
Iran. Using an academic orientation, the conceptual research is focusing on the
determinants of a successful migration from legacy to cloud computing. The
study attempts to reveal the constructive effects and deconstructive defects of
migration to cloud computing with a close regard into prior literature and
practical practices all around the world. Conceptual frameworks are deducted
from the literature and Telco's revolutionary movements toward cloud computing.
The confirmatory quantitative approach tries to verify or reject the validity
of determinants of successful migration. The study reports that there are some
success and failure factors which are influencing a successful migration of
data centres and servers of Iranian Telecommunication to the cloud. Considering
these approved factors before any migration decision would be valuable for
engaged project members and finally for Telecommunication organization. This
paper can be used as reliable model for any migration beforehand taking any
action. Enforcing proper determinants in accordance with the prior success
stories and academia viewpoints in Telecommunication industry in Iran as a
first mover research in this field provides a precious insight for policy and
decision makers to change their mindset and grant a proper space for cloud
computing to grow in this industry due to its advantages. Obviously, like any
other big Telco in the world, Iranian Telco might start cloud projects to
sustain its presence in the global market.


title: The 3-adic eigencurve at the boundary of weight space

abstract:
  This paper generalizes work of Buzzard and Kilford to the case $p=3$, giving
an explicit bound for the overconvergence of the quotient $E_\kappa /
V(E_\kappa)$ and using this bound to prove that the eigencurve is a union of
countably many annuli over the boundary of weight space.


title:
Strong competition versus fractional diffusion: the case of
  Lotka-Volterra interaction

abstract:
  We consider a system of differential equations with nonlinear Steklov
boundary conditions, related to the fractional problem $$(-\Delta)^s u_i =
f_i(x,u_i) - \beta u_i^p \sum_{j\neq i} a_{ij} u_j^p,$$ where $i = i,\dots, k$,
$s\in(0,1)$, $p>0$, $a_{ij}>0$ and $\beta>0$. When $k=2$ we develop a
quasi-optimal regularity theory in $C^{0,\alpha}$, uniformly w.r.t. $\beta$,
for every $\alpha < \alpha_{\mathrm opt}=min(1,2s)$; moreover we show that the
traces of the limiting profiles as $\beta\to+\infty$ are Lipschitz continuous
and segregated. Such results are extended to the case of $k\geq3$ densities,
with some restrictions on $s$, $p$ and $a_{ij}$.


title: Morphologies of protostellar outflows: An ALMA view

abstract:
  The formation of stars is usually accompanied by the launching of
protostellar outflows. Observations with the Atacama Large
Millimetre/sub-millimetre Array (ALMA) will soon revolutionalise our
understanding of the morphologies and kinematics of these objects. In this
paper, we present synthetic ALMA observations of protostellar outflows based on
numerical magnetohydrodynamic collapse simulations. We find significant
velocity gradients in our outflow models and a very prominent helical structure
within the outflows. We speculate that the disk wind found in the ALMA Science
Verification Data of HD 163296 presents a first instance of such an
observation.


title:
Depletion interaction effects on the tunneling conductivity of nanorod
  suspensions

abstract:
  We study by simulation and theory how the addition of insulating spherical
particles affects the conductivity of fluids of conducting rods, modeled by
spherocylinders. The electrical connections are implemented as tunneling
processes, leading to a more detailed and realistic description than a
discontinuous percolation approach. We find that the spheres enhance the
tunneling conductivity for a given concentration of rods and that the
enhancement increases with rod concentration into the regime where the
conducting network is well established. By reformulating the network of rods
using a critical path analysis, we quantify the effect of depletion-induced
attraction between the rods due to the spheres. Furthermore, we show that our
conductivity data are quantitatively reproduced by an effective medium
approximation, which explicitly relates the system tunneling conductance to the
structure of the rod-sphere fluid.


title:
Dynamics of a single-mode semiconductor laser with incoherent optical
  feedback

abstract:
  A novel model of a semiconductor laser with optical feedback is presented,
generalizing Lang-Kobayashi equations to the case of incoherent feedback. The
equations are supplemented by a stochastic variable which models random phase
difference between the field inside laser cavity and the feedback field. It is
shown that for weak-to-moderate feedback the transition from coherent to
incoherent feedback leads to replacement of dynamical chaos by almost
stationary lasing with slightly fluctuating intensity. Nevertheless, incoherent
feedback can lead to chaotic oscillations, but at considerably larger feedback
levels.


title: Total Transversals and Total Domination in Uniform Hypergraphs

abstract:
  The first three authors [European J. Combin. 33 (2012), 62--71] established a
relationship between the transversal number and the domination number of
uniform hypergraphs. In this paper, we establish a relationship between the
total transversal number and the total domination number of uniform
hypergraphs. We prove tight asymptotic upper bounds on the total transversal
number in terms of the number of vertices, the number of edges, and the edge
size.


title:
Cold Rydberg atoms for quantum simulation of exotic condensed matter
  interactions

abstract:
  Quantum simulators could provide an alternative to numerical simulations for
understanding minimal models of condensed matter systems in a controlled way.
Typically, cold atom systems are used to simulate e.g. Hubbard models. In this
paper, we discuss a range of exotic interactions that can be formed when cold
Rydberg atoms are loaded into optical lattices with unconventional geometries;
such as long-range electron-phonon interactions and extended Coulomb like
interactions. We show how these can lead to proposals for quantum simulators
for complex condensed matter systems such as superconductors. Continuous time
quantum Monte Carlo is used to compare the proposed schemes with the physics
found in traditional condensed matter Hamiltonians for systems such as high
temperature superconductors.


title: BPS states in the Omega-background and torus knots

abstract:
  We clarify some issues concerning the central charges saturated by the
extended objects in the SUSY $U(1)$ $4d$ gauge theory in the
$\Omega$-background. The configuration involving the monopole localized at the
domain wall is considered in some details. At the rational ratio
$\frac{\epsilon_1}{\epsilon_2}=\frac{p}{q}$ the trajectory of the monopole
provides the torus $(p,q)$ knot in the squashed three-sphere. Using the
relation between the integrable systems of Calogero type at the rational
couplings and the torus knots we interpret this configuration in terms of the
auxiliary $2d$ quiver theory or $3d$ theory with nontrivial boundary
conditions. This realization can be considered as the AGT-like representation
of the torus knot invariants.


title: Laser Tomography Adaptive Optics (LTAO): A performance study

abstract:
  We present an analytical derivation of the on-axis performance of Adaptive
Optics systems using a given number of guide stars of arbitrary altitude,
distributed at arbitrary angular positions in the sky. The expressions of the
residual error are given for cases of both continuous and discrete turbulent
atmospheric profiles. Assuming Shack-Hartmann wavefront sensing with circular
apertures, we demonstrate that the error is formally described by integrals of
products of three Bessel functions. We compare the performance of Adaptive
Optics correction when using natural, Sodium or Rayleigh laser guide stars. For
small diameter class telescopes (~5m), we show that a few number of Rayleigh
beacons can provide similar performance to that of a single Sodium laser, for a
lower overall cost of the instrument. For bigger apertures, using Rayleigh
stars may not be such a suitable alternative because of the too severe cone
effect that drastically degrades the quality of the correction.


title: The Boundary of Amoebas

abstract:
  The computation of amoebas has been a challenging open problem for the last
dozen years. The most natural approach, namely to compute an amoeba via its
boundary, has not been practical so far since only a superset of the boundary,
the contour, is understood in theory and computable in practice.
  We define and characterize the extended boundary of an amoeba, which is
sensitive to some degenerations that the topological boundary does not detect.
Our description of the extended boundary also allows us to distinguish between
the contour and the boundary. This gives rise not only to new structural
results in amoeba theory, but in particular allows us to compute hypersurface
amoebas via their boundary in any dimension. In dimension two this can be done
using Gr\"obner bases alone.
  We introduce the concept of amoeba bases, which are sufficient for
understanding the amoeba of an ideal. We show that our characterization of the
boundary is essential for the computation of these amoeba bases and we
illustrate the potential of this concept by constructing amoeba bases for
linear systems of equations.


title: Non-complete intersection prime ideals in dimension 3

abstract:
  We describe prime ideals of height 2 minimally generated by 3 elements in a
Gorenstein, Nagata local ring of Krull dimension 3 and multiplicity at most 3.
This subject is related to a conjecture of Y. Shimoda and to a long-standing
problem of J. Sally.


title:
Deuterated water in the solar-type protostars NGC 1333 IRAS 4A and IRAS
  4B

abstract:
  Aims. The aim of this paper is to study deuterated water in the solar-type
protostars NGC1333 IRAS4A and IRAS4B, to compare their HDO abundance
distribution with other star-forming regions, and to constrain their HDO/H2O
ratios. Methods. Using the Herschel/HIFI instrument as well as ground-based
telescopes, we observed several HDO lines covering a large excitation range
(Eup/k=22-168 K) towards these protostars and an outflow position. Non-LTE
radiative transfer codes were then used to determine the HDO abundance profiles
in these sources. Results. The HDO fundamental line profiles show a very broad
component, tracing the molecular outflows, in addition to a narrower emission
component and a narrow absorbing component. In the protostellar envelope of
NGC1333 IRAS4A, the HDO inner (T>100 K) and outer (T<100 K) abundances with
respect to H2 are estimated at 7.5x10^{-9} and 1.2x10^{-11}, respectively,
whereas, in NGC1333 IRAS4B, they are 1.0x10^{-8} and 1.2x10^{-10},
respectively. Similarly to the low-mass protostar IRAS16293-2422, an absorbing
outer layer with an enhanced abundance of deuterated water is required to
reproduce the absorbing components seen in the fundamental lines at 465 and 894
GHz in both sources. This water-rich layer is probably extended enough to
encompass the two sources as well as parts of the outflows. In the outflows
emanating from NGC1333 IRAS4A, the HDO column density is estimated at about
(2-4)x10^{13} cm^{-2}, leading to an abundance of about (0.7-1.9)x10^{-9}. An
HDO/H2O ratio between 7x10^{-4} and 9x10^{-2} is derived in the outflows. In
the warm inner regions of these two sources, we estimate the HDO/H2O ratios at
about 1x10^{-4}-4x10^{-3}. This ratio seems higher (a few %) in the cold
envelope of IRAS4A, whose possible origin is discussed in relation to formation
processes of HDO and H2O.


title:
Heavy-flavour production in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76
  TeV with the ALICE detector

abstract:
  Hadrons containing heavy-flavours, i.e. charm and beauty quarks, are unique
probes of the properties of the hot and dense QCD medium produced in heavy-ion
collisions. Due to their large masses, heavy quarks are produced at the initial
stage of the collision, almost exclusively via hard partonic scattering
processes. Therefore, they are expected to experience the full collision
history propagating through and interacting with the QCD medium. The parton
energy loss, which is sensitive to the transport coefficients of the produced
medium, can be studied experimentally by measuring the nuclear modication
factor ($R_{\rm AA}$) which accounts for the modication of the heavy-flavoured
hadron yield in Pb-Pb collisions with respect to pp collisions. In semi-central
Pb-Pb collisions, the degree of thermalization of charm quarks in the QCD
medium can be accessed via the measurement of the heavy flavour elliptic flow
$v_2$ at low $p_{\rm T}$ . At high $p_{\rm T}$, $v_2$ is sensitive to the
path-length dependence of heavy quark in-medium energy loss. The ALICE
collaboration has measured the production of open heavy flavour hadrons via
their hadronic and semi-leptonic decays at mid-rapidity and in the semi-muonic
decay channel at forward rapidity in pp, p-Pb and Pb-Pb collisions at 7, 5.02
and 2.76 TeV respectively. In this talk the current results on open
heavy-flavour $R_{\rm AA}$ and $v_2$ will be presented.


title: Semantic Description of Web Services

abstract:
  The tasks of semantic web service (discovery, selection, composition, and
execution) are supposed to enable seamless interoperation between systems,
whereby human intervention is kept at a minimum. In the field of Web service
description research, the exploitation of descriptions of services through
semantics is a better support for the life-cycle of Web services. The large
number of developed ontologies, languages of representations, and integrated
frameworks supporting the discovery, composition and invocation of services is
a good indicator that research in the field of Semantic Web Services (SWS) has
been considerably active. We provide in this paper a detailed classification of
the approaches and solutions, indicating their core characteristics and
objectives required and provide indicators for the interested reader to follow
up further insights and details about these solutions and related software.


title:
Formulation and Steady-state Analysis of LMS Adaptive Networks for
  Distributed Estimation in the Presence of Transmission Errors

abstract:
  This article presents the formulation and steady-state analysis of the
distributed estimation algorithms based on the diffusion cooperation scheme in
the presence of errors due to the unreliable data transfer among nodes. In
particular, we highlight the impact of transmission errors on the least-mean
squares (LMS) adaptive networks. We develop the closed-form expressions of the
steady-state mean-square deviation (MSD) which is helpful to assess the effects
of the imperfect information flow on on the behavior of the diffusion LMS
algorithm in terms of the steady-state error. The model is then validated by
performing Monte Carlo simulations. It is shown that local and global MSD
curves are not necessarily monotonic increasing functions of the error
probability. We also assess sufficient conditions that ensure mean and
mean-square stability of diffusion LMS strategies in the presence of
transmission errors. Moreover, issues such as scalability in the sense of
network size and regressor size, spatially correlated observations, as well as
the effect of the distribution of the noise variance are studied.
  While the proposed theoretical framework is general in the sense that it is
not confined to a particular source of error during information diffusion, for
practical reasons we additionally study a specific scenario where errors occur
at the medium access control (MAC) level. We develop a model to quantify the
MAC-level transmission errors according to the network topology and system
parameters for a set of nodes employing a backoff procedure to access the
channel. To overcome the problem of unreliable data exchange, we propose an
enhanced combining rule that can be deployed in order to improve the
performance of diffusion estimation algorithms by using the knowledge of the
properties of the transmission errors.


title:
The tautological ring of the space of pointed genus two curves of
  compact type

abstract:
  We prove that the tautological ring of $M_{2,n}^{ct}$, the moduli space of
n-pointed genus two curves of compact type, does not have Poincar\'e duality
for any $n \geq 8$. This result is obtained via a more general study of the
cohomology groups of $M_{2,n}^{ct}$. We explain how the cohomology can be
decomposed into pieces corresponding to different local systems and how the
tautological cohomology can be identified within this decomposition. Our
results allow the computation of $H^k(M_{2,n}^{ct})$ for any $k$ and $n$
considered both as $S_n$-representation and as mixed Hodge
structure/$\ell$-adic Galois representation considered up to
semi-simplification. A consequence of our results is also that all even
cohomology of $\overline M_{2,n}$ is tautological for $n < 20$, and that the
tautological ring of $\overline M_{2,n}$ fails to have Poincar\'e duality for
all $n \geq 20$. This improves and simplifies results of the author and Orsola
Tommasi.


title: Symmetry and the thermodynamics of currents in open quantum systems

abstract:
  Symmetry is a powerful concept in physics, and its recent application to
understand nonequilibrium behavior is providing deep insights and
groundbreaking exact results. Here we show how to harness symmetry to control
transport and statistics in open quantum systems. Such control is enabled by a
first-order-type dynamic phase transition in current statistics and the
associated coexistence of different transport channels (or nonequilibrium
steady states) classified by symmetry. Microreversibility then ensues, via the
Gallavotti-Cohen fluctuation theorem, a twin dynamic phase transition for rare
current fluctuations. Interestingly, the symmetry present in the initial state
is spontaneously broken at the fluctuating level, where the quantum system
selects the symmetry sector that maximally facilitates a given fluctuation. We
illustrate these results in a qubit network model motivated by the problem of
coherent energy harvesting in photosynthetic complexes, and introduce the
concept of a symmetry-controlled quantum thermal switch, suggesting
symmetry-based design strategies for quantum devices with controllable
transport properties.

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


title:
Synthesis of High-Quality Graphene through Electrochemical Exfoliation
  of Graphite in Alkaline Electrolyte

abstract:
  Owing to wide variety of applications of graphene, high-quality and
economical way of synthesizing graphene is highly desirable. In this study, we
report a cost effective and simple approach to production of high-quality
graphene. Here the synthesis route is based on electrochemical exfoliation of
graphite. Instead of using strong acids (which oxidise and damage the
geometrical topology of graphene), we have used alkaline solution (KOH
dissolved in water) as electrolyte. TEM analysis shows that as prepared
graphene has 1-4 layers and large lateral size (up to ~18 micrometer). Raman
analysis shows a unique feature. The D peak which is invariably present in
graphene is absent here. This suggests that disorder in the graphene sheets
synthesized by the present method, is nearly absent. A tentative mechanism of
electrochemical exfoliation in alkaline electrolyte is discussed and described.


title:
Beyond the Standard Model B-parameters with improved staggered fermions
  in $N_f=2+1$ QCD

abstract:
  We calculate the kaon mixing B-parameters for operators arising generically
in theories of physics beyond the standard model. We use HYP-smeared improved
staggered fermions on the $N_f = 2+1$ MILC asqtad lattices. Operator matching
is done perturbatively at one-loop order. Chiral extrapolations are done using
"golden combinations" in which one-loop chiral logarithms are absent. For the
combined sea-quark mass and continuum extrapolation, we use three lattice
spacings: $a \approx 0.045, 0.06$ and $0.09 \text{fm}$. Our results have a
total error of 5-6%, which is dominated by the systematic error from matching
and continuum extrapolation. For two of the BSM $B$-parameters, we agree with
results obtained using domain-wall and twisted-mass dynamical fermions, but we
disagree by $(4-5)\sigma$ for the other two.


title:
Transition densities for strongly degenerate time inhomogeneous random
  models

abstract:
  In this paper we study the existence of densities for strongly degenerate
stochastic differential equations whose coefficients depend on time and are not
globally Lipschitz. In these models neither local ellipticity nor the strong
H\"ormander condition is satisfied. In this general setting we show that
continuous transition densities indeed exist in all neighborhoods of points
where the weak H\"ormander condition is satisfied. We also exhibit regions
where these densities remain positive. We then apply these results to
stochastic Hodgkin-Huxley models as a first step towards the study of
ergodicity properties of such systems.


title: Status Report of LPCC Forward Physics Group

abstract:
  We report here about activities of newly formed working group aiming to
define a forward and diffractive physics program at the LHC for the years to
come.


title:
Injection locking of two frequency-doubled lasers with 3.2 GHz offset
  for driving Raman transitions with low photon scattering in $^{43}$Ca$^+$

abstract:
  We describe the injection locking of two infrared (794 nm) laser diodes which
are each part of a frequency-doubled laser system. An acousto-optic modulator
(AOM) in the injection path gives an offset of 1.6 GHz between the lasers for
driving Raman transitions between states in the hyperfine split (by 3.2 GHz)
ground level of $^{43}$Ca$^+$. The offset can be disabled for use in
$^{40}$Ca$^+$. We measure the relative linewidth of the frequency-doubled beams
to be 42 mHz in an optical heterodyne measurement. The use of both injection
locking and frequency doubling combines spectral purity with high optical
power. Our scheme is applicable for providing Raman beams across other ion
species and neutral atoms where coherent optical manipulation is required.


title: Eccentricity of the nodes of OTIS-cube and Enhanced OTIS-cube

abstract:
  In this paper we have classified the nodes of OTIS-cube based on their
eccentricities. OTIS (optical transpose interconnection system) is a large
scale optoelectronic computer architecture, proposed in \cite{KMKE92}, that
benefit from both optical and electronic technologies. We show that radius and
diameter of OTIS-$Q_n$ is $n+1$ and $2n+1$ respectively. We also show that
average eccentricity of OTIS-cube is $(3n/2+1)$.
  In \cite{D05}, a variant of OTIS-cube, called Enhanced OTIS-cube
(E-OTIS-$Q_n$) was proposed.
  E-OTIS-$Q_n$ is regular of degree $n+1$ and maximally fault-tolerant.
  In this paper we have given a classification of the nodes of E-OTIS cube and
derived expressions for the eccentricities of the nodes in each class. Based on
these results we show that radius and diameter of E-OTIS-$Q_n$ is $n+1$ and
$\lfloor {4n+4/3} \rfloor$ respectively. We have also computed the average
eccentricity of E-OTIS-$Q_n$ for values of $n$ upto 20.


title: S-duality constraint on higher-derivative couplings

abstract:
  The Riemann curvature correction to the type II supergravity at
eight-derivative level in string frame is given as
e^{-2\phi}(t_8t_8R^4+\frac{1}{4}\eps_{8}\eps_{8}R^4). For constant dilaton, it
has been extended in the literature to the S-duality invariant form by
extending the dilaton factor in the Einstein frame to the non-holomorphic
Eisenstein series. For non-constant dilaton, however, there are various
couplings in the Einstein frame which are not consistent with the S-duality. By
constructing the tensors $t_{2n}$ from Born-Infeld action, we include the
appropriate Ricci and scalar curvatures as well as the dilaton couplings to
make the above action to be consistent with the S-duality.


title:
H Index Communication Journals according to Google Scholar Metrics
  (2008-2012)

abstract:
  The aim of this report is to present a ranking of Communication journals
covered in Google Scholar Metrics for the period 2008-2012. It corresponds to
the H Index update made last year for the period 2007-2011 (Delgado
L\'opez-C\'ozar and Repiso 2013). Google Scholar Metrics doesnt currently allow
to group and sort all journals belonging to a scientific discipline. In the
case of Communication, in the ten listings displayed by GSM we can only locate
46 journals. Therefore, in an attempt to overcome this limitation, we have used
the diversity of search procedures allowed by GSM to identify the greatest
number of scientific journals of Communication with H Index calculated by this
bibliometric tool. The result is a ranking of 354 communication journals sorted
by the same H Index, and mean as discriminating value. Journals are also
grouped by quartiles.


title: Decomposition matrices for low rank unitary groups

abstract:
  We study the decomposition matrices for the unipotent $\ell$-blocks of finite
special unitary groups SU$_n(q)$ for unitary primes $\ell$ larger than $n$. Up
to very few unknown entries, we give a complete solution for $n=2,\ldots,10$.
We also prove a general result for two-column partitions when $\ell$ divides
$q+1$. This is achieved using projective modules coming from the $\ell$-adic
cohomology of Deligne--Lusztig varieties.


title:
Radial Transport of Large-Scale Magnetic Fields in Accretion Disks. II.
  Relaxation to Steady States

abstract:
  We study the time evolution of a large-scale magnetic flux threading an
accretion disk. Induction equation of the mean poloidal field is solved under
the standard viscous disk model. Magnetic flux evolution is controlled by the
two timescales: One is the timescale of the inward advection of the magnetic
flux, tau_{adv}. This is induced by the dragging of the flux by the accreting
gas. The other is the outward diffusion timescale of the magnetic flux
tau_{dif}. We consider diffusion due to the Ohmic resistivity. These timescales
can be significantly different from the disk viscous timescale tau_{disk}. The
behaviors of the magnetic flux evolution is quite different depending on the
magnitude relationship of the timescales tau_{adv}, \tau_{dif}, and tau_{disk}.
The most interesting phenomena occurs when tau_{adv} << tau_{dif}, tau_{disk}.
In such a case, the magnetic flux distribution approaches a quasi-steady
profile much faster than the viscous evolution of the gas disk, and also the
magnetic flux has been tightly bundled to the inner part of the disk. In the
inner part, although the poloidal magnetic field becomes much stronger than the
interstellar magnetic field, the field strength is limited to the maximum value
that is analytically given by our previous work (Okuzumi et al. 2014, ApJ, 785,
127). We also find a condition for that the initial large magnetic flux, which
is a fossil of the magnetic field dragging during the early phase of star
formation, survives for a duration in which significant gas disk evolution
proceeds.


title: Andreev reflection in monolayer MoS2

abstract:
  Andreev reflection in a monolayer molybdenum disulfide superconducting-normal
(S/N) hybrid junction is investigated. We find, by using a modified-Dirac
Hamiltonian and the scattering formalism, that the perfect Andreev reflection
happens at normal incidence with $p$-doped S and N regions. The probability of
the Andreev reflection and the resulting Andreev conductance, in this system,
are demonstrated to be large in comparison with corresponding gapped graphene
structure. We further investigate the effect of a topological term ($\beta)$ in
the Hamiltonian and show that it results in an enhancement of the Andreev
conductance with $p$-doped S and N regions, while in the corresponding
structure with $n$-doped S region it is strongly reducible in comparison. This
effect can be explained in terms of the dependence of the Andreev reflection
probability on the sign of $\beta$ and the chemical potential in the
superconducting region.


title: Variations of the spectral excess theorem for normal digraphs

abstract:
  It is known that every distance-regular digraph is connected and normal. An
interesting question is: when is a given connected normal digraph
distance-regular? Motivated by this question first we give some
characterizations of weakly distance-regular digraphs. Specially we show that
whether a given connected digraph to be weakly distance-regular only depends on
the equality for two invariants. Then we show that a connected normal digraph
$\G$ with $d+1$ distinct eigenvalues is distance-regular if and only if the
simple excess (the ratio of the square of mean of the numbers of shortest paths
between vertices at distance $d$ to the mean of the numbers of vertices at
distance $d$ from every vertex, which is zero if $d$ is greater than the
diameter) is equal to the spectral excess (a number which can be computed from
the spectrum of $\G$). In fact, this result is a new variation (a simple
variation) of the spectral excess theorem due to Fiol and Garigga for connected
normal digraphs. Using these results we derive another variation (a weighted
variation) of the spectral excess theorem for connected normal digraphs.
Distance regularity of a digraph (also a graph) is in general not determined by
its spectrum. For application of the simple variation we show that distance
regularity of a connected normal digraph $\G$ (with $d+1$ distinct eigenvalues)
is determined by its spectrum and the invariant $\delta_d$ (the mean of the
numbers of vertices at distance $d$ from every vertex). Finally as an
application of the weighted variation we show that every connected normal
digraph $\G$ with $d+1$ distinct eigenvalues and diameter $D$ is either a
bipartite digraph, or a generalized odd graph or it has odd-girth at most
$\min\{2d-1,2D+1\}$, generalizing a result of van Dam and Haemers and also a
recent result of Lee and Weng.


title: Unveiling the dust nucleation zone of IRC+10216 with ALMA

abstract:
  We report the detection in IRC+10216 of lines of HNC $J$=3-2 pertaining to 9
excited vibrational states with energies up to $\sim$5300 K. The spectrum,
observed with ALMA, also shows a surprising large number of narrow,
unidentified lines that arise in the vicinity of the star. The HNC data are
interpreted through a 1D--spherical non--local radiative transfer model,
coupled to a chemical model that includes chemistry at thermochemical
equilibrium for the innermost regions and reaction kinetics for the external
envelope. Although unresolved by the present early ALMA data, the radius
inferred for the emitting region is $\sim$0.06'' (i.e., $\simeq$ 3 stellar
radii), similar to the size of the dusty clumps reported by IR studies of the
innermost region ($r <$ 0.3''). The derived abundance of HNC relative to H$_2$
is $10^{-8} <$ $\chi$(HNC) $< 10^{-6}$, and drops quickly where the gas density
decreases and the gas chemistry is dominated by reaction kinetics. Merging HNC
data with that of molecular species present throughout the inner envelope, such
as vibrationally excited HCN, SiS, CS, or SiO, should allow us to characterize
the physical and chemical conditions in the dust formation zone.


title:
Nucleon pair approximation description of the low-lying structure of
  $^{108,109}$Te and $^{109}$I

abstract:
  The low-lying level schemes and electromagnetic transitions of $^{109}$Te,
$^{109}$I, and the neighboring even-even nucleus $^{108}$Te, are calculated
within the framework of the $SD$-pair approximation of the nuclear shell model.
Good agreement is obtained between the calculated results and experimental
data. The favored components of low-lying bands are discussed in the collective
nucleon-pair subspace. The weak-coupling picture shown in these nuclei and its
relationship with residual quadrupole-quadrupole interaction between valence
protons and neutrons are analyzed.


title:
On 4D, N = 1 Massless Gauge Superfields of Higher Superspin: Integer
  Case

abstract:
  We present an alternative method of exploring the component structure of an
integer super-helicity Y=s (for any integers) irreducible representation of the
Super-Poincare group. We use it to derive the component action and the SUSY
transformation laws. The effectiveness of this approach is based on the
equations of motion and their properties, like Bianchi identities. These
equations are generated by the superspace action when it is expressed in terms
of prepotentials. For that reason we reproduce the superspace action for
integer superspin, using unconstrained superfields. The appropriate, to use,
superfields are dictated by the representation theory of the group and the
requirement that there is a smooth limit between the massive and massless case.


title:
On 4D, N = 1 Massless Gauge Superfields of Higher Superspin:
  Half-Odd-Integer Case

abstract:
  We present an alternative method to explore the off-shell component structure
of theories that describe half-integer super-helicities Y=s+1/2 (where sis any
positive integer). We use it to derive the component action, component SUSY
transformation laws, and count the component-level degrees of freedom involved.
This counting will give us clues about N=2 representations. The foundation of
the process relies on the superfield equations of motion, generated by
variation of a superspace action expressed in terms of prepotentials. Using
this approach we reproduce the half-integer super-helicity superspace action
using unconstrained superfields.


title: A Dynamical Theory for Massive Supergravity

abstract:
  We present a new massive theory of superspin Y=3/2 which has non-minimal
supergravity as it's massless limit. The new result will illuminate the
underlying structure of auxiliary fields required for the description of
arbitrary massive half-integer superspin systems.


title: Groups in the Millennium Simulation and in SDSS DR7

abstract:
  The Millennium N-body simulation and the Sloan Digital Sky Survey seventh
data release (SDSS DR7) galaxy and galaxy group catalogues are compared to
study the properties of galaxy groups and the distribution of galaxies in
groups. We construct mock galaxy group catalogues for a Millennium
semi-analytical galaxy catalogue by using the same friends-of-friends method,
which was used by Tago et al to analyse the SDSS data. We analyse in detail the
group luminosities, group richnesses, virial radii, sizes of groups and their
rms velocities for four volume-limited samples from observations and
simulations. Our results show that the spatial densities of groups agree within
one order of magnitude in all samples with a rather good agreement between the
mock catalogues and observations. All group property distributions have similar
shapes and amplitudes for richer groups. For galaxy pairs and small groups, the
group properties for observations and simulations are clearly different. In
addition, the spatial distribution of galaxies in small groups is different: at
the outskirts of the groups the galaxy number distributions do not agree,
although the agreement is relatively good in the inner regions. Differences in
the distributions are mainly due to the observational limitations in the SDSS
sample and to the problems in the semi-analytical methods that produce too
compact and luminous groups.


title:
Exclusive $c \to s,d$ semileptonic decays of spin-1/2 and spin-3/2 $cb$
  baryons

abstract:
  We present results for exclusive semileptonic decay widths of ground state
spin-$1/2$ and spin-$3/2$ $cb$ baryons corresponding to a $c\to s, d$
transition at the quark level. The relevance of hyperfine mixing in spin-1/2
$cb$ baryons is shown. Our form factors are compatible with heavy quark spin
symmetry constraints obtained in the infinite heavy quark mass limit.


title: Passing the Einstein-Rosen bridge

abstract:
  We relax the requirement of geodesic completeness of a space-time. Instead,
we require test particles trajectories to be smooth only in the physical
sector. Test particles trajectories for Einstein--Rosen bridge are proved to be
smooth in the physical sector, and particles can freely penetrate the bridge in
both directions.


title:
Semilinear elliptic problems in unbounded domains with unbounded
  boundary

abstract:
  This paper deals with a class of singularly perturbed nonlinear elliptic
problems $(P_\e)$ with subcritical nonlinearity.
  The coefficient of the linear part is assumed to concentrate in a point of
the domain, as $\e\to 0$, and the domain is supposed to be unbounded and with
unbounded boundary.
  Domains that enlarge at infinity, and whose boundary flattens or shrinks at
infinity, are considered.
  It is proved that in such domains problem $(P_\e)$ has at least 2 solutions.


title: Monopoles on the Bryant-Salamon $G_2$ Manifolds

abstract:
  $G_2$-Monopoles are solutions to gauge theoretical equations on noncompact
$7$-manifolds of $G_2$ holonomy. We shall study this equation on the $3$
Bryant-Salamon manifolds. We construct examples of $G_2$-monopoles on two of
these manifolds, namely the total space of the bundle of anti-self-dual two
forms over the $\mathbb{S}^4$ and $\mathbb{CP}^2$. These are the first
nontrivial examples of $G_2$-monopoles. Associated with each monopole there is
a parameter $m \in \mathbb{R}^+$, known as the mass of the monopole. We prove
that under a symmetry assumption, for each given $m \in \mathbb{R}^+$ there is
a unique monopole with mass $m$. We also find explicit irreducible
$G_2$-instantons on $\Lambda^2_-(\mathbb{S}^4)$ and on
$\Lambda^2_-(\mathbb{CP}^2)$. The third Bryant-Salamon $G_2$-metric lives on
the spinor bundle over the $3$-sphere. In this case we produce a vanishing
theorem for monopoles.


title: Models of Finsler Geometry on Lie algebroids

abstract:
  Horizontal endomorphisms, almost complex structures, vertical, horizontal and
complete lifts on prolongation of a Lie algebroid are considered. Then using
exact sequences, semisprays are constructed. Moreover, important geometrical
objects such as classical distinguished connections, torsions and partial
curvatures are studied on prolongation of Lie algebroids. Considering pullback
bundle, covariant derivatives are scrutinized based on anchor map. Several
Finsler geometry models on Lie algebroid structures, will organized via recent
arguments. Finally, it will be overhaulled some special Finsler Lie algebroid
spaces.


title: Calabi-Yau structures on cotangent bundles

abstract:
  Starting with an orientable compact real-analytic Riemannian manifold $(L,g)$
with $\chi(L)=0$, we show that a small neighbourhood $ \textrm{Op}(L) $ of the
zero section in the cotangent bundle $T^{*}L$ carries a Calabi-Yau structure
such that the zero section is an isometrically embedded special Lagrangian
submanifold.


title: Instability of enclosed horizons

abstract:
  We point out that there are solutions to the scalar wave equation on 1+1
dimensional Minkowski space with finite energy tails which, if they reflect off
a uniformly accelerated mirror due to (say) Dirichlet boundary conditions on
it, develop an infinite stress-energy tensor on the mirror's Rindler horizon.
We also show that, in the presence of an image mirror in the opposite Rindler
wedge, suitable compactly supported arbitrarily small initial data on a
suitable initial surface will develop an arbitrarily large stress-energy scalar
near where the two horizons cross. Also, while there is a regular
Hartle-Hawking-Israel-like state for the quantum theory between these two
mirrors, there are coherent states built on it for which there are similar
singularities in the expectation value of the renormalized stress-energy
tensor. We conjecture that in other situations with analogous enclosed horizons
such as a (maximally extended) Schwarzschild black hole in equilibrium in a
(stationary spherical) box or the (maximally extended) Schwarzschild-AdS
spacetime, there will be similar stress-energy singularities and
almost-singularities -- leading to instability of the horizons when gravity is
switched on and matter and gravity perturbations are allowed for. All this
suggests it is incorrect to picture a black hole in equilibrium in a box or a
Schwarzschild-AdS black hole as extending beyond the past and future horizons
of a single Schwarzschild (/Schwarzschild-AdS) wedge. It would thus provide new
evidence for 't Hooft's brick wall model while seeming to invalidate the
picture in Maldacena's 'Eternal black holes in AdS'. It would thereby also
support the validity of the author's matter-gravity entanglement hypothesis and
of the paper 'Brick walls and AdS/CFT' by the author and Ort\'iz.


title: Searches for beyond Standard Model Higgs bosons at CMS

abstract:
  A search for neutral Higgs bosons in the minimal supersymmetric extension of
the Standard Model (MSSM) decaying to a pair of b quarks or a pair of tau
leptons, using events recorded by the CMS experiment at the LHC in 2011 and
2012 at the centre-of-mass energy of 7 TeV and 8 TeV respectively, is
presented. The result is also presented for a search for the charged Higgs
boson that can be produced in the top quark decay with subsequent decay of H+
in tau and neutrino. Results are also reported from a search for
non-standard-model Higgs boson decays to pairs of new light bosons, each of
which decays into the di-muon final state.