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arxiv_dataset-39001212.0384 | New Skyrme energy density functional for a better description of the
Gamow-Teller Resonance
nucl-th astro-ph.SR
We present a new Skyrme energy density functional (EDF) named SAMi [Phys.
Rev. C 86 031306(R)]. This interaction has been accurately calibrated to
reproduce properties of doubly-magic nuclei and infinite nuclear matter. The
novelties introduced in the model and fitting protocol of SAMi are crucial for
a better description of the Gamow-Teller Resonance (GTR). Those are, on one
side, the two-component spin-orbit potential needed for describing different
proton high-angular momentum spin-orbit splitings and, on the other side, the
careful description of the empirical hierarchy and positive values found in
previous analysis of the spin (G_0) and spin-isospin (G_0^') Landau-Migdal
parameters: 0 < G_0 < G_0^', a feature that many of available Skyrme forces
fail to reproduce. When employed within the self-consistent Hartree-Fock plus
Random Phase Approximation, SAMi produces results on ground and excited state
nuclear properties that are in good agreement with experimental findings. This
is true not only for the GTR, but also for the Spin Dipole Resonance (SDR) and
the Isobaric Analog Resonance (IAR) as well as for the non charge-exchange
Isoscalar Giant Monopole (ISGMR) and Isovector Giant Dipole (IVGDR) and
Quadrupole Resonances (IVGQR).
| arxiv topic:nucl-th astro-ph.SR |
arxiv_dataset-39011212.0484 | On stability of power-law solution in multidimensional Gauss-Bonnet
cosmology
gr-qc hep-th
We consider dynamics of a flat anisotropic multidimensional cosmological
model in Gauss-Bonnet gravity in the presence of a homogeneous magnetic field.
In particular, we find conditions under which the known power-law vacuum
solution can be an attractor for the case with non-zero magnetic field. We also
describe a particular class of numerical solution in $(5+1)$-dimensional case
which does not approach the power-law regime.
| arxiv topic:gr-qc hep-th |
arxiv_dataset-39021212.0584 | Robust tripartite-to-bipartite entanglement localization by weak
measurements and reversal
quant-ph
We propose a robust and efficient approach for tripartite-to-bipartite
entanglement localization. By using weak measurements and quantum measurement
reversal, an almost maximal entangled state shared by two parties can be
generated with the assistance of the third party by local quantum operations
and classical communication from a W-like state. We show that this approach
works well in the presence of losses and phase diffusion. Our method provides
an active way to fight against decoherence, and might help for quantum
communication and distributed quantum computation.
| arxiv topic:quant-ph |
arxiv_dataset-39031212.0684 | Dynamics of scaled norms of vorticity for the three-dimensional
Navier-Stokes and Euler equations
nlin.CD math-ph math.MP
A series of numerical experiments is suggested for the three-dimensional
Navier-Stokes and Euler equations on a periodic domain based on a set of
$L^{2m}$-norms of vorticity $\Omega_{m}$ for $m\geq 1$. These are scaled to
form the dimensionless sequence $D_{m}=
(\varpi_{0}^{-1}\Omega_{m})^{\alpha_{m}}$ where $\varpi_{0}$ is a constant
frequency and $\alpha_{m} = 2m/(4m-3)$. A numerically testable Navier-Stokes
regularity criterion comes from comparing the relative magnitudes of $D_{m}$
and $D_{m+1}$ while another is furnished by imposing a critical lower bound on
$\int_{0}^{t}D_{m}\,d\tau$. The behaviour of the $D_{m}$ is also important in
the Euler case in suggesting a method by which possible singular behaviour
might also be tested.
| arxiv topic:nlin.CD math-ph math.MP |
arxiv_dataset-39041212.0784 | Magnetized hot neutron matter: lowest order constrained variational
calculations
nucl-th astro-ph.SR
We have studied the spin polarized hot neutron matter in the presence of
strong magnetic field. In this work, using the lowest order constrained
variational method at finite temperature and employing $AV_{18}$ nuclear
potential, some thermodynamic properties of spin polarized neutron matter such
as spin polarization parameter, free energy, equation of state and effective
mass have been calculated. It has been shown that the strong magnetic field
breaks the symmetry of the free energy, leading to a magnetized equilibrium
state. We have found that the equation of state becomes stiffer by increasing
both magnetic field and temperature. The magnetic field dependence of effective
mass for the spin-up and spin-down neutrons has been investigated.
| arxiv topic:nucl-th astro-ph.SR |
arxiv_dataset-39051212.0884 | Maximizing Social Influence in Nearly Optimal Time
cs.DS cs.SI physics.soc-ph
Diffusion is a fundamental graph process, underpinning such phenomena as
epidemic disease contagion and the spread of innovation by word-of-mouth. We
address the algorithmic problem of finding a set of k initial seed nodes in a
network so that the expected size of the resulting cascade is maximized, under
the standard independent cascade model of network diffusion. Runtime is a
primary consideration for this problem due to the massive size of the relevant
input networks.
We provide a fast algorithm for the influence maximization problem, obtaining
the near-optimal approximation factor of (1 - 1/e - epsilon), for any epsilon >
0, in time O((m+n)k log(n) / epsilon^2). Our algorithm is runtime-optimal (up
to a logarithmic factor) and substantially improves upon the previously
best-known algorithms which run in time Omega(mnk POLY(1/epsilon)).
Furthermore, our algorithm can be modified to allow early termination: if it is
terminated after O(beta(m+n)k log(n)) steps for some beta < 1 (which can depend
on n), then it returns a solution with approximation factor O(beta). Finally,
we show that this runtime is optimal (up to logarithmic factors) for any beta
and fixed seed size k.
| arxiv topic:cs.DS cs.SI physics.soc-ph |
arxiv_dataset-39061212.0984 | $^{75}$As NMR study of overdoped CeFeAsO$_{0.8}$F$_{0.2}$
cond-mat.supr-con
We report the results from a $^{75}$As NMR study on the overdoped iron
pnictide superconductor, CeFeAsO$_{0.8}$F$_{0.2}$. Two peaks are observed in
the NMR spectra for temperatures as high as 100 K, which is above the
superconducting transition temperature of 39 K and hence they cannot be
attributed to the effect of vortices in the superconducting state as previously
suggested [A. Ghoshray, et al., Phys. Rev. B 79, 144512 (2009)]. The
temperature dependence of the $^{75}$As NMR shifts for the two peaks is
consistent with hyperfine coupling from magnetic Ce to As and with different
Curie-Weiss temperatures. The appearance of two Curie-Weiss temperatures where
one is near zero and the other is $\sim$-18 K suggests that the two peaks arise
from ordered and disordered regions where the disorder could be due to regions
with significant fluorine site disorder and/or clusters of oxygen vacancies.
Similar to some other studies on ReFeAsO$_{1-x}$F$_x$ (Re is a rare earth) we
find that there are more than one $^{75}$As spin-lattice and spin-spin
relaxation rates that can be attributed to ordered and disordered regions in
the ReO layer and suggests that inhomogeneity is a common feature in the
ReFeAsO$_{1-x}$F$_x$ superconductors.
| arxiv topic:cond-mat.supr-con |
arxiv_dataset-39071212.1084 | Forced generation of simple and double emulsions in all-aqueous system
physics.flu-dyn
We report an easy-to-implement method that allows the direct generation of
water-in-water (w/w) single emulsions. The method relies on direct perturbation
of the pressure that drives the flow of the dispersed phase of the emulsions.
The resultant inner jet is induced to break up into droplets due to the growth
of the perturbation through Rayleigh-Plateau instability [L. Rayleigh, Proc. R.
Soc. London 29, 71-97 (1879)]; this leads to the formation of monodisperse
droplets. By implementing this method on a modified microfluidic device, we
directly generate water-in-water-in-water (w/w/w) double emulsions with good
control over the size and the number of encapsulated droplets. Our approach
suggests a new route to apply droplet-based microfluidics to completely
water-based systems.
| arxiv topic:physics.flu-dyn |
arxiv_dataset-39081212.1184 | Phase diagram and surface tension in the three-flavor
Polyakov-quark-meson model
hep-ph hep-th nucl-th
We obtain the in-medium effective potential of the three-flavor
Polyakov-Quark-Meson model as a real function of real variables in the Polyakov
loop variable, to allow for the study of all possible minima of the model. At
finite quark chemical potential, the real and imaginary parts of the effective
potential, in terms of the Polyakov loop variables, are made apparent, showing
explicitly the fermion sign problem of the theory. The phase diagram and other
equilibrium observables, obtained from the real part of the effective
potential, are calculated in the mean-field approximation. The obtained results
are compared to those found with the so-called saddle-point approach. Our
procedure also allows the calculation of the surface tension between the
chirally broken and confined phase, and the chirally restored and deconfined
phase. The values of surface tension we find for low temperatures are very
close to the ones recently found for two-flavor chiral models. Some
consequences of our results for the early Universe, for heavy-ion collisions,
and for proto-neutron stars are briefly discussed.
| arxiv topic:hep-ph hep-th nucl-th |
arxiv_dataset-39091212.1284 | Integrated Green Cloud Computing Architecture
cs.DC
Arbitrary usage of cloud computing, either private or public, can lead to
uneconomical energy consumption in data processing, storage and communication.
Hence, green cloud computing solutions aim not only to save energy but also
reduce operational costs and carbon footprints on the environment. In this
paper, an Integrated Green Cloud Architecture (IGCA) is proposed that comprises
of a client-oriented Green Cloud Middleware to assist managers in better
overseeing and configuring their overall access to cloud services in the
greenest or most energy-efficient way. Decision making, whether to use local
machine processing, private or public clouds, is smartly handled by the
middleware using predefined system specifications such as service level
agreement (SLA), Quality of service (QoS), equipment specifications and job
description provided by IT department. Analytical model is used to show the
feasibility to achieve efficient energy consumption while choosing between
local, private and public Cloud service provider (CSP).
| arxiv topic:cs.DC |
arxiv_dataset-39101212.1384 | Clusters and water flows: a novel approach to modal clustering through
Morse theory
math.ST math.DG stat.ML stat.TH
The problem of finding groups in data (cluster analysis) has been extensively
studied by researchers from the fields of Statistics and Computer Science,
among others. However, despite its popularity it is widely recognized that the
investigation of some theoretical aspects of clustering has been relatively
sparse. One of the main reasons for this lack of theoretical results is surely
the fact that, unlike the situation with other statistical problems as
regression or classification, for some of the cluster methodologies it is quite
difficult to specify a population goal to which the data-based clustering
algorithms should try to get close. This paper aims to provide some insight
into the theoretical foundations of the usual nonparametric approach to
clustering, which understands clusters as regions of high density, by
presenting an explicit formulation for the ideal population clustering.
| arxiv topic:math.ST math.DG stat.ML stat.TH |
arxiv_dataset-39111212.1484 | Dynamics of quantum correlations in colored environments
quant-ph
We address the dynamics of entanglement and quantum discord for two non
interacting qubits initially prepared in a maximally entangled state and then
subjected to a classical colored noise, i.e. coupled with an external
environment characterized by a noise spectrum of the form $1/f^{\alpha}$. More
specifically, we address systems where the Gaussian approximation fails, i.e.
the sole knowledge of the spectrum is not enough to determine the dynamics of
quantum correlations. We thus investigate the dynamics for two different
configurations of the environment: in the first case the noise spectrum is due
to the interaction of each qubit with a single bistable fluctuator with an
undetermined switching rate, whereas in the second case we consider a
collection of classical fluctuators with fixed switching rates. In both cases
we found analytical expressions for the time dependence of entanglement and
quantum discord, which may be also extended to a collection of flcutuators with
random switching rates. The environmental noise is introduced by means of
stochastic time-dependent terms in the Hamiltonian and this allows us to
describe the effects of both separate and common environments. We show that the
non-Gaussian character of the noise may lead to significant effects, e.g.
environments with the same power spectrum, but different configurations, give
raise to opposite behavior for the quantum correlations. In particular,
depending on the characteristics of the environmental noise considered, both
entanglement and discord display either a monotonic decay or the phenomena of
sudden death and revivals. Our results show that the microscopic structure of
environment, besides its noise spectrum, is relevant for the dynamics of
quantum correlations, and may be a valid starting point for the engineering of
non-Gaussian colored environments.
| arxiv topic:quant-ph |
arxiv_dataset-39121212.1584 | On some integral inequalities for s-logarithmically convex functions and
their applications
math.FA math.CA
In this paper, we describe s-logarithmically convex functions in the first
and second sense which are connected with the ordinary logatihmic convex and
s-convex in the first and second sense. Afterwards, some new inequalities
related to above new definitions are given.
| arxiv topic:math.FA math.CA |
arxiv_dataset-39131212.1684 | Assessing the Bias in Communication Networks Sampled from Twitter
physics.soc-ph cs.SI
We collect and analyse messages exchanged in Twitter using two of the
platform's publicly available APIs (the search and stream specifications). We
assess the differences between the two samples, and compare the networks of
communication reconstructed from them. The empirical context is given by
political protests taking place in May 2012: we track online communication
around these protests for the period of one month, and reconstruct the network
of mentions and re-tweets according to the two samples. We find that the search
API over-represents the more central users and does not offer an accurate
picture of peripheral activity; we also find that the bias is greater for the
network of mentions. We discuss the implications of this bias for the study of
diffusion dynamics and collective action in the digital era, and advocate the
need for more uniform sampling procedures in the study of online communication.
| arxiv topic:physics.soc-ph cs.SI |
arxiv_dataset-39141212.1784 | The mid-infrared environments of 6.7 GHz Methanol Masers from the
Methanol Multi-Beam Survey
astro-ph.SR astro-ph.GA
We present a study of the mid-infrared environments and association with star
formation tracers of 6.7 GHz methanol masers taken from the Methanol Multi-Beam
(MMB) Survey. Our ultimate goal is to establish the mass of the host star and
its evolutionary stage for each maser site. As a first step, the GLIMPSE survey
of the Galactic Plane is utilised to investigate the environment of 776
methanol masers and we find that while the majority of the masers are
associated with mid-infrared counterparts, a significant fraction (17%) are not
associated with any detectable mid-infrared emission. A number of the maser
counterparts are clearly extended with respect to the GLIMPSE point spread
function and we implement an adaptive non-circular aperture photometry (ANCAP)
technique to determine the fluxes of the maser counterparts. The ANCAP
technique doubles the number of masers with flux information at all four
wavelengths compared to the number of the corresponding counterparts obtained
from the GLIMPSE Point Source Catalogue. The colours of the maser counterparts
are found to be very similar to the smaller study carried out by Ellingsen
(2006). The MMB masers are weakly associated with Extended Green Objects (EGOs)
and Red MSX Survey (RMS) embedded sources (YSO and HII classifications) with
18% and 12% of masers associated with these objects respectively. The majority
of MMB masers (60%) have detectable GLIMPSE infrared counterparts but have not
been identified with previously recognised tracers of massive star formation;
this confirms that the MMB survey has the potential to identify massive star
forming regions independent of infrared selection.
| arxiv topic:astro-ph.SR astro-ph.GA |
arxiv_dataset-39151212.1884 | Convergence to Equilibrium of Logit Dynamics for Strategic Games
cs.GT cs.DM cs.DS
We present the first general bounds on the mixing time of the Markov chain
associated to the logit dynamics for wide classes of strategic games. The logit
dynamics with inverse noise beta describes the behavior of a complex system
whose individual components act selfishly and keep responding according to some
partial ("noisy") knowledge of the system, where the capacity of the agent to
know the system and compute her best move is measured by the inverse of the
parameter beta.
In particular, we prove nearly tight bounds for potential games and games
with dominant strategies. Our results show that, for potential games, the
mixing time is upper and lower bounded by an exponential in the inverse of the
noise and in the maximum potential difference. Instead, for games with dominant
strategies, the mixing time cannot grow arbitrarily with the inverse of the
noise.
Finally, we refine our analysis for a subclass of potential games called
graphical coordination games, a class of games that have been previously
studied in Physics and, more recently, in Computer Science in the context of
diffusion of new technologies. We give evidence that the mixing time of the
logit dynamics for these games strongly depends on the structure of the
underlying graph. We prove that the mixing time of the logit dynamics for these
games can be upper bounded by a function that is exponential in the cutwidth of
the underlying graph and in the inverse of noise. Moreover, we consider two
specific and popular network topologies, the clique and the ring. For games
played on a clique we prove an almost matching lower bound on the mixing time
of the logit dynamics that is exponential in the inverse of the noise and in
the maximum potential difference, while for games played on a ring we prove
that the time of convergence of the logit dynamics to its stationary
distribution is significantly shorter.
| arxiv topic:cs.GT cs.DM cs.DS |
arxiv_dataset-39161212.1984 | Geo-Indistinguishability: Differential Privacy for Location-Based
Systems
cs.CR
The growing popularity of location-based systems, allowing unknown/untrusted
servers to easily collect huge amounts of information regarding users'
location, has recently started raising serious privacy concerns. In this paper
we study geo-indistinguishability, a formal notion of privacy for
location-based systems that protects the user's exact location, while allowing
approximate information - typically needed to obtain a certain desired service
- to be released. Our privacy definition formalizes the intuitive notion of
protecting the user's location within a radius r with a level of privacy that
depends on r, and corresponds to a generalized version of the well-known
concept of differential privacy. Furthermore, we present a perturbation
technique for achieving geo-indistinguishability by adding controlled random
noise to the user's location. We demonstrate the applicability of our technique
on a LBS application. Finally, we compare our mechanism with other ones in the
literature. It turns our that our mechanism offers the best privacy guarantees,
for the same utility, among all those which do not depend on the prior.
| arxiv topic:cs.CR |
arxiv_dataset-39171212.2084 | Synchrotron emission driven by the Cherenkov-drift instability in active
galactic nuclei
astro-ph.HE astro-ph.CO
In the present paper we study generation of the synchrotron emission by means
of the feedback of Cherenkov drift waves on the particle distribution via the
diffusion process. It is shown that despite the efficient synchrotron losses
the excited Cherenkov drift instability leads to the quasi-linear diffusion
(QLD), effect of which is balanced by dissipation factors and as a result the
pitch angles are prevented from damping, maintaining the corresponding
synchrotron emission. The model is analyzed for a wide range of physical
parameters and it is shown that the mechanism of QLD guarantees the generation
of electromagnetic radiation from soft $X$-rays up to soft $\gamma$-rays,
strongly correlated with Cherenkov drift emission ranging from IR up to UV
energy domains.
| arxiv topic:astro-ph.HE astro-ph.CO |
arxiv_dataset-39181212.2184 | Quark back reaction to deconfinement transition via gluon propagators
hep-ph hep-lat
Contribution of the quark back reaction to the deconfinement phase transition
is studied in the thermodynamical potential of the gluonic sector which
consists of the gluon and ghost propagators calculated in the lattice QCD
simulations. Starting from QCD thermodynamic potential, we define the gluonic
potential in the leading-order of the 2PI formalism, which can describe the
deconfinement phase transition. Then the gluonic potential can be written by
using the microscopic characters; the gluon and ghost propagators in Landau
gauge fixing. To include effects of the quark back reaction, we calculate the
gluon propagators in lattice QCD simulations with two-flavored dynamical
quarks. Fitting the lattice data by the Gribov-Stingl form and investigating
the phase transition of the gluonic potential, we find that enhancement of the
quark back reaction reduces the critical temperature of the deconfinement phase
transition.
| arxiv topic:hep-ph hep-lat |
arxiv_dataset-39191212.2284 | The Complexity of Planar Boolean #CSP with Complex Weights
cs.CC cs.DS
We prove a complexity dichotomy theorem for symmetric complex-weighted
Boolean #CSP when the constraint graph of the input must be planar. The
problems that are #P-hard over general graphs but tractable over planar graphs
are precisely those with a holographic reduction to matchgates. This
generalizes a theorem of Cai, Lu, and Xia for the case of real weights. We also
obtain a dichotomy theorem for a symmetric arity 4 signature with complex
weights in the planar Holant framework, which we use in the proof of our #CSP
dichotomy. In particular, we reduce the problem of evaluating the Tutte
polynomial of a planar graph at the point (3,3) to counting the number of
Eulerian orientations over planar 4-regular graphs to show the latter is
#P-hard. This strengthens a theorem by Huang and Lu to the planar setting. Our
proof techniques combine new ideas with refinements and extensions of existing
techniques. These include planar pairings, the recursive unary construction,
the anti-gadget technique, and pinning in the Hadamard basis.
| arxiv topic:cs.CC cs.DS |
arxiv_dataset-39201212.2384 | Mode visibilities in rapidly rotating stars
astro-ph.SR
Context: Mode identification is a crucial step to comparing observed
frequencies with theoretical ones, but has proven to be difficult in rapidly
rotating stars.
Aims: To further constrain mode identification, we aim to accurately
calculate mode visibilities and amplitude ratios in rapid rotators.
Methods: We derive the relevant equations for calculating mode visibilities
in different photometric bands while fully taking into account the geometric
distortion from both the centrifugal deformation and the pulsation modes, the
variations in effective gravity, and an approximate treatment of the
temperature variations. These equations are then applied to 2D oscillation
modes, calculated using the TOP code, in fully distorted 2D models based on the
SCF method. The specific intensities come from a grid of Kurucz atmospheres,
thereby taking into account limb and gravity darkening.
Results: We obtain mode visibilities and amplitude ratios for 2 M_{\odot}
models rotating at 0 to 80 % of the critical rotation rate. These calculations
confirm previous results, such as the increased visibility of chaotic modes,
the simpler frequency spectra of pole-on stars, or the dependence of amplitude
ratios on inclination and azimuthal order. In addition, the geometric shape of
the star reduces the contrast between pole-on and equator-on visibilities of
island modes. We also show that modes with similar (ell, |m|) values frequently
have similar amplitude ratios, even in the most rapidly rotating models.
| arxiv topic:astro-ph.SR |
arxiv_dataset-39211212.2484 | Decision Making with Partially Consonant Belief Functions
cs.AI
This paper studies decision making for Walley's partially consonant belief
functions (pcb). In a pcb, the set of foci are partitioned. Within each
partition, the foci are nested. The pcb class includes probability functions
and possibility functions as extreme cases. Unlike earlier proposals for a
decision theory with belief functions, we employ an axiomatic approach. We
adopt an axiom system similar in spirit to von Neumann - Morgenstern's linear
utility theory for a preference relation on pcb lotteries. We prove a
representation theorem for this relation. Utility for a pcb lottery is a
combination of linear utility for probabilistic lottery and binary utility for
possibilistic lottery.
| arxiv topic:cs.AI |
arxiv_dataset-39221212.2584 | Recent Theoretical Developments in Strongly Coupled QCD
nucl-th hep-ph hep-th
Heavy-ion collisions involve strongly coupled dynamics of QCD in the entire
history of time evolution. We review recent theoretical efforts to meet this
challenge, focusing on the two approaches that the speaker has contributed to:
1) Holography or AdS/CFT correspondence, and 2) Symmetry protected phenomena
such as those originating from triangle anomaly. The presentation is oriented
to non-experts on these fields, and hence relies on intuitive pictures of the
methods and the results, without going into specific details.
| arxiv topic:nucl-th hep-ph hep-th |
arxiv_dataset-39231212.2684 | Correlated Electron Materials and Field Effect Transistors for Logic: A
Review
cond-mat.str-el cond-mat.mtrl-sci cond-mat.supr-con
Correlated electron systems are among the centerpieces of modern condensed
matter sciences, where many interesting physical phenomena, such as
metal-insulator transition and high-Tc superconductivity appear. Recent efforts
have been focused on electrostatic doping of such materials to probe the
underlying physics without introducing disorder as well as to build
field-effect transistors that may complement conventional semiconductor
metal-oxide-semiconductor field effect transistor (MOSFET) technology. This
review focuses on metal-insulator transition mechanisms in correlated electron
materials and three-terminal field effect devices utilizing such correlated
oxides as the channel layer. We first describe how electron-disorder
interaction, electron-phonon interaction and/or electron correlation in solids
could modify the electronic properties of materials and lead to metal-insulator
transitions. Then we analyze experimental efforts toward utilizing these
transitions in field effect transistors and their underlying principles. It is
pointed out that correlated electron systems show promise among these various
materials displaying phase transitions for logic technologies. Furthermore,
novel phenomena emerging from electronic correlation could enable new
functionalities in field effect devices. We then briefly review unconventional
electrostatic gating techniques, such as ionic liquid gating and ferroelectric
gating, which enables ultra large carrier accumulation density in the
correlated materials which could in turn lead to phase transitions. The review
concludes with a brief discussion on the prospects and suggestions for future
research directions in correlated oxide electronics for information processing.
| arxiv topic:cond-mat.str-el cond-mat.mtrl-sci cond-mat.supr-con |
arxiv_dataset-39241212.2784 | Clustering of functional boxplots for multiple streaming time series
stat.ME stat.ML
In this paper we introduce a micro-clustering strategy for Functional
Boxplots. The aim is to summarize a set of streaming time series splitted in
non overlapping windows. It is a two step strategy which performs at first, an
on-line summarization by means of functional data structures, named Functional
Boxplot micro-clusters; then it reveals the final summarization by processing,
off-line, the functional data structures. Our main contribute consists in
providing a new definition of micro-cluster based on Functional Boxplots and,
in defining a proximity measure which allows to compare and update them. This
allows to get a finer graphical summarization of the streaming time series by
five functional basic statistics of data. The obtained synthesis will be able
to keep track of the dynamic evolution of the multiple streams.
| arxiv topic:stat.ME stat.ML |
arxiv_dataset-39251212.2884 | Direct capture in the $^{130}$Sn(n,$\gamma$)$^{131}$Sn and
$^{132}$Sn(n,$\gamma$)$^{133}$Sn reactions under $r$-process conditions
nucl-th astro-ph.IM
The cross sections of the $^{130}$Sn(n,$\gamma$)$^{131}$Sn and
$^{132}$Sn(n,$\gamma$)$^{133}$Sn reactions are calculated in the direct capture
model at low energies below 1.5\,MeV. Using recent data from (d,p) transfer
experiments on $^{130}$Sn and $^{132}$Sn, it is possible to avoid global input
parameters with their inherent uncertainties and to determine all input to the
direct capture model by local adjustments. The calculated direct capture cross
sections of $^{130}$Sn and $^{132}$Sn are almost identical and have
uncertainties of less than a factor of two. The stellar reaction rates $N_A <
\sigma v >$ show a slight increase with temperature. Finally an estimate for
the influence of low-lying resonances to the stellar reaction rates is given.
| arxiv topic:nucl-th astro-ph.IM |
arxiv_dataset-39261212.2984 | Melt-Enhanced Rejuvenation of Lithospheric Mantle: Insights from the
Colorado Plateau
physics.geo-ph
The stability of the lithospheric mantle beneath the ancient cratonic cores
of continents is primarily a function of chemical modification during the
process of melt extraction. Processes by which stable continental lithosphere
may be destabilized are not well-understood, although destabilization by
thickening and removal of negatively-buoyant lithospheric mantle in
"delamination" events has been proposed in a number of tectonic settings. In
this paper we explore an alternative process for destabilizing continents,
namely, thermal and chemical modification during infiltration of metasomatic
fluids and melts into the lithospheric column. We consider observations
pertinent to the structure and evolution of the Colorado Plateau within the
western United States to argue that the physical and chemical state of the
margins of the plateau have been variably modified and destabilized by
interaction with melts. In the melt-infiltration process explored here, the
primary mechanism for weakening and rejuvenating the plate is through thermal
effects and the feedback between deformation and melt-infiltration. We
speculate on the nature and geometry of a melt-modulated interaction zone
between lithosphere and asthenosphere and the seismically-observable
consequences of variable melt-infiltration into the margins of regions of
thick, stable lithosphere such as the Colorado Plateau and the Archean Wyoming
Province within North America.
| arxiv topic:physics.geo-ph |
arxiv_dataset-39271212.3084 | Application of Simulated Tempering and Magnetizing to a Two-Dimensional
Potts Model
cond-mat.stat-mech physics.comp-ph
We applied the simulated tempering and magnetizing (STM) method to the
two-dimensional three-state Potts model in an external magnetic field in order
to perform further investigations of the STM's applicability. The temperature
as well as the external field are treated as dynamical variables updated during
the STM simulations. After we obtained adequate information for several lattice
sizes $L$ (up to $160\times 160$), we also performed a number of conventional
canonical simulations of large lattices, especially in order to illustrate the
crossover behavior of the Potts model in external field with increasing $L$.
The temperature and external field for larger lattice size simulations were
chosen by extrapolation of the detail information obtained by STM. We carefully
analyzed the crossover scaling at the phase transitions with respect to the
lattice size as well as the temperature and external field. The crossover
behavior is clearly observed in the simulations in agreement with theoretical
predictions.
| arxiv topic:cond-mat.stat-mech physics.comp-ph |
arxiv_dataset-39281212.3184 | Do we have the explanation for the Higgs and Yukawa couplings of the
standard model?
hep-ph
The spin-charge-family theory offers a possible explanation for the
assumptions of the standard model, interpreting the standard model as its low
energy effective manifestation. The theory predicts several scalar fields
determining masses and mixing matrices of fermions and weak bosons. The scalar
fields manifest as doublets with respect to the weak charge, while they are
triplets with respect to the family quantum numbers. Since free scalar fields
(mass eigen states) differ from those which couple to $Z_m$ and to
$W^{\pm}_{m}$ or to each family member of each of the family the
spin-charge-family theory predictions for LHC might differ from those of the
standard model.
| arxiv topic:hep-ph |
arxiv_dataset-39291212.3284 | Invariant distributions and scaling limits for some diffusions in
time-varying random environments
math.PR
We consider a family of one-dimensional diffusions, in dynamical Wiener
mediums, which are random perturbations of the Ornstein-Uhlenbeck diffusion
process. We prove quenched and annealed convergences in distribution and under
weighted total variation norms. We find two kind of stationary probability
measures, which are either the standard normal distribution or a
quasi-invariant measure, depending on the environment, and which is naturally
connected to a random dynamical system. We apply these results to the study of
a model of time-inhomogeneous Brox's diffusions, which generalizes the
diffusion studied by Brox (1986) and those investigated by Gradinaru and Offret
(2011). We point out two distinct diffusive behaviours and we give the speed of
convergences in the quenched situations.
| arxiv topic:math.PR |
arxiv_dataset-39301212.3384 | Proximity breakdown of hydrides in superconducting niobium cavities
cond-mat.supr-con physics.acc-ph
Many modern and proposed future particle accelerators rely on superconducting
radio frequency cavities made of bulk niobium as primary particle accelerating
structures. Such cavities suffer from the anomalous field dependence of their
quality factors Q0. High field degradation - so-called high field Q-slope - is
yet unexplained even though an empirical cure is known. Here we propose a
mechanism based on the presence of proximity-coupled niobium hydrides, which
can explain this effect. Furthermore, the same mechanism can be present in any
surface-sensitive experiments or superconducting devices involving niobium.
| arxiv topic:cond-mat.supr-con physics.acc-ph |
arxiv_dataset-39311212.3484 | Anomalies in a waterlike model confined between plates
physics.chem-ph cond-mat.soft
Using molecular dynamic simulations we study a waterlike model confined
between two fixed hydrophobic plates. The system is tested for density,
diffusion and structural anomalous behavior and compared with the bulk results.
Within the range of confining distances we had explored we observe that in the
pressure-temperature phase diagram the temperature of maximum density (TMD
line), the temperature of maximum and minimum diffusion occur at lower
temperatures when compared with the bulk values. For distances between the two
layers below a certain threshold ,$d\le d_c$, only two layers of particles are
formed, for $d\ge d_c$ three or more layers are formed. In the case of three
layers the central layer stays liquid while the contact layers crystallize.
This result is in agreement with simulations for atomistic models.
| arxiv topic:physics.chem-ph cond-mat.soft |
arxiv_dataset-39321212.3584 | GPDs at an EIC
nucl-th hep-ex nucl-ex
The feasibility for a measurement of the exclusive production of a real
photon, a process although known as Deeply Virtual Compton Scattering (DVCS) at
an Electron Ion Collider (EIC) has been explored. DVCS is universally believed
to be a golden measurement toward the determination of the Generalized Parton
Distribution (GPDs) functions. The high luminosity of the machine, expected in
the order of 10^34 cm^-2 s^-1 at the highest center-of-mass energy, together
with the large resolution and rapidity acceptance of a newly designed dedicated
detector, will open a opportunity for very high precision measurements of DVCS,
and thus for the determination of GPDs, providing an important tool toward a
2+1 dimensional picture of the internal structure of the proton and nuclei.
| arxiv topic:nucl-th hep-ex nucl-ex |
arxiv_dataset-39331212.3684 | Square functions with general measures
math.CA
We characterize the boundedness of square functions in the upper half-space
with general measures. The short proof is based on an averaging identity over
good Whitney regions.
| arxiv topic:math.CA |
arxiv_dataset-39341212.3784 | $Z_b/Z_b^\prime \to \Upsilon\pi$ and $h_b \pi$ decays in intermediate
meson loops model
hep-ph hep-ex
With the recent measurement of $Z_b(10610)$ and $Z_b(10650)\to
B\bar{B}^*+c.c.$ and $B^*\bar{B}^*$, we investigate the transitions from the
$Z_b(10610)$ and $Z_b(10650)$ to bottomonium states with emission of a pion via
intermediate $B \ {B}^*$ meson loops. The experimental data can be reproduced
in this approach with a commonly accepted range of values for the form factor
cutoff parameter $\alpha$. The $\Upsilon(3S)\pi$ decay channels appear to
experience obvious threshold effects which can be understood by the property of
the loop integrals. By investigating the $\alpha$-dependence of partial decay
widths and ratios between different decay channels, we show that the
intermediate $B \ {B}^*$ meson loops are crucial for driving the transitions of
$Z_b/Z_b'\to \Upsilon(nS)\pi$ with $n = 1, 2, 3$, and $h_b(mP)\pi$ with $m = 1$
and 2.
| arxiv topic:hep-ph hep-ex |
arxiv_dataset-39351212.3884 | Extracting Unsatisfiable Cores for LTL via Temporal Resolution
cs.LO
Unsatisfiable cores (UCs) are a well established means for debugging in a
declarative setting. Still, there are few tools that perform automated
extraction of UCs for LTL. Existing tools compute a UC as an unsatisfiable
subset of the set of top-level conjuncts of an LTL formula. Using resolution
graphs to extract UCs is common in other domains such as SAT. In this article
we construct and optimize resolution graphs for temporal resolution as
implemented in the temporal resolution-based solver TRP++, and we use them to
extract UCs for propositional LTL. The resulting UCs are more fine-grained than
the UCs obtained from existing tools because UC extraction also simplifies
top-level conjuncts instead of treating them as atomic entities. For example,
given an unsatisfiable LTL formula of the form $\phi \equiv ({\bf G} \psi)
\wedge {\bf F} \psi'$ existing tools return $\phi$ as a UC irrespective of the
complexity of $\psi$ and $\psi'$, whereas the approach presented in this
article continues to remove parts not required for unsatisfiability inside
$\psi$ and $\psi'$. Our approach also identifies groups of occurrences of a
proposition that do not interact in a proof of unsatisfiability. We implement
our approach in TRP++. Our experimental evaluation demonstrates that our
approach (i) extracts UCs that are often significantly smaller than the input
formula with an acceptable overhead and (ii) produces more fine-grained UCs
than competing tools while remaining at least competitive in terms of run time
and memory usage. The source code of our tool is publicly available.
| arxiv topic:cs.LO |
arxiv_dataset-39361212.3984 | Possible Indications of Electronic Inhomogeneities in Superconducting
Nanowire Detectors
cond-mat.supr-con
The voltage-carrying state of superconducting NbTiN nanowires, used for
single-photon detectors, is analyzed. Upon lowering the current, the wire
returns to the superconducting state in a steplike pattern, which differs from
sample to sample. Elimination of geometrical inhomogeneities, such as sharp
corners, does not remove these steplike features. They appear to be intrinsic
to the material. Since the material is strongly disordered, electronic
inhomogeneities are considered as a possible cause. A thermal model, taking
into account random variations of the electronic properties along the wire, is
used as an interpretative framework.
| arxiv topic:cond-mat.supr-con |
arxiv_dataset-39371212.4084 | A Combinatorial Approach to Nonlocality and Contextuality
quant-ph math.CO
So far, most of the literature on (quantum) contextuality and the
Kochen-Specker theorem seems either to concern particular examples of
contextuality, or be considered as quantum logic. Here, we develop a general
formalism for contextuality scenarios based on the combinatorics of hypergraphs
which significantly refines a similar recent approach by Cabello, Severini and
Winter (CSW). In contrast to CSW, we explicitly include the normalization of
probabilities, which gives us a much finer control over the various sets of
probabilistic models like classical, quantum and generalized probabilistic. In
particular, our framework specializes to (quantum) nonlocality in the case of
Bell scenarios, which arise very naturally from a certain product of
contextuality scenarios due to Foulis and Randall. In the spirit of CSW, we
find close relationships to several graph invariants. The recently proposed
Local Orthogonality principle turns out to be a special case of a general
principle for contextuality scenarios related to the Shannon capacity of
graphs. Our results imply that it is strictly dominated by a low level of the
Navascu\'es-Pironio-Ac\'in hierarchy of semidefinite programs, which we also
apply to contextuality scenarios.
We derive a wealth of results in our framework, many of these relating to
quantum and supraquantum contextuality and nonlocality, and state numerous open
problems. For example, we show that the set of quantum models on a
contextuality scenario can in general not be characterized in terms of a graph
invariant.
In terms of graph theory, our main result is this: there exist two graphs
$G_1$ and $G_2$ with the properties \begin{align*} \alpha(G_1) &= \Theta(G_1),
& \alpha(G_2) &= \vartheta(G_2), \\[6pt] \Theta(G_1\boxtimes G_2) & >
\Theta(G_1)\cdot \Theta(G_2),& \Theta(G_1 + G_2) & > \Theta(G_1) + \Theta(G_2).
\end{align*}
| arxiv topic:quant-ph math.CO |
arxiv_dataset-39381212.4184 | Weighted Bergman spaces and the $\bar{\partial}-$equation
math.CV
We give a H\"ormander type $L^2-$estimate for the $\bar{\partial}-$equation
with respect to the measure $\delta_\Omega^{-\alpha}dV$, $\alpha<1$, on any
bounded pseudoconvex domain with $C^2-$boundary. Several applications to the
function theory of weighed Bergman spaces $A^2_\alpha(\Omega)$ are given,
including a corona type theorem, a Gleason type theorem, together with a
density theorem. We investigate in particular the boundary behavior of
functions in $A^2_\alpha(\Omega)$ by proving an analogue of the Levi problem
for $A^2_\alpha(\Omega)$ and giving an optimal Gehring type estimate for
functions in $A^2_\alpha(\Omega)$. A vanishing theorem for $A^2_1(\Omega)$ is
established for arbitrary bounded domains. Relations between the weighted
Bergman kernel and the Szeg\"o kernel are also discussed.
| arxiv topic:math.CV |
arxiv_dataset-39391212.4284 | On periodic points of free inverse monoid endomorphisms
math.GR cs.FL
It is proved that the periodic point submonoid of a free inverse monoid
endomorphism is always finitely generated. Using Chomsky's hierarchy of
languages, we prove that the fixed point submonoid of an endomorphism of a free
inverse monoid can be represented by a context-sensitive language but, in
general, it cannot be represented by a context-free language.
| arxiv topic:math.GR cs.FL |
arxiv_dataset-39401212.4384 | Comment on "Creating artificial magnetic fields for cold atoms by
photon-assisted tunneling" by Kolovsky A.R
cond-mat.quant-gas
We comment briefly on the scheme proposed in EPL 93, 20003 (2011) to produce
synthetic gauge fields by means of photon-assisted tunneling.
| arxiv topic:cond-mat.quant-gas |
arxiv_dataset-39411212.4484 | Combining and comparing neutrinoless double beta decay experiments using
different nuclei
hep-ph hep-ex nucl-ex nucl-th
We perform a global fit of the most relevant neutrinoless double beta decay
experiments within the standard model with massive Majorana neutrinos. Using
Bayesian inference makes it possible to take into account the theoretical
uncertainties on the nuclear matrix elements in a fully consistent way. First,
we analyze the data used to claim the observation of neutrinoless double beta
decay in Ge-76, and find strong evidence (according to Jeffrey's scale) for a
peak in the spectrum and moderate evidence for that the peak is actually close
to the energy expected for the neutrinoless decay. We also find a significantly
larger statistical error than the original analysis, which we include in the
comparison with other data. Then, we statistically test the consistency between
this claim with that of recent measurements using Xe-136. We find that the two
data sets are about 40 to 80 times more probable under the assumption that they
are inconsistent, depending on the nuclear matrix element uncertainties and the
prior on the smallest neutrino mass. Hence, there is moderate to strong
evidence of incompatibility, and for equal prior probabilities the posterior
probability of compatibility is between 1.3% and 2.5%. If one, despite such
evidence for incompatibility, combines the two data sets, we find that the
total evidence of neutrinoless double beta decay is negligible. If one ignores
the claim, there is weak evidence against the existence of the decay. We also
perform approximate frequentist tests of compatibility for fixed ratios of the
nuclear matrix elements, as well as of the no signal hypothesis. Generalization
to other sets of experiments as well as other mechanisms mediating the decay is
possible.
| arxiv topic:hep-ph hep-ex nucl-ex nucl-th |
arxiv_dataset-39421212.4584 | Resources needed for non-unitary quantum operations
quant-ph
Non-unitary operations generated by an effective non-Hermitian Hamiltonian
can be used to create quantum state manipulations which are impossible in
Hermitian quantum mechanics. These operations include state preparation (or
cooling) and non-orthogonal state discrimination. In this work we put a lower
bound on the resources needed for the construction of some given non-unitary
evolution. Passive systems are studied in detail and a general feature of such
a system is derived. After interpreting our results using the singular value
decomposition, several examples are studied analytically. In particular, we put
a lower bound on the resources needed for non-Hermitian state preparation and
non-orthogonal state discrimination.
| arxiv topic:quant-ph |
arxiv_dataset-39431212.4684 | Is there a "Charge - Magnet Paradox"
physics.gen-ph
In this paper it is shown that in the approach to special relativity which
exclusively deals with the four-dimensional geometric quantities (4D GQs), the
invariant special relativity (ISR), there is not recently posed paradox that in
a static electric field a magnetic dipole moment (MDM) is subject to a torque
in some frames and not in others. In the ISR, there is no need either for the
change of the Lorentz force, but as a 4D GQ, or for the introduction of some
"hidden" 3D quantities. Furthermore, in the ISR, contrary to all previous
approaches, an electrically neutral current-loop in its rest frame possesses
not only a MDM m, but also an electric dipole moment (EDM) p and a stationary
permanent magnet possesses not only an intrinsic magnetization M but also an
intrinsic electric polarization P. Hence, in a static electric field, both, a
current-loop and a permanent magnet experience the Lorentz force K_{L} and the
torque N in all relatively moving inertial frames. The quantities m, p, M, P,
K_{L}, N are the 4D GQs.
| arxiv topic:physics.gen-ph |
arxiv_dataset-39441212.4784 | Phenomenology Tools on Cloud Infrastructures using OpenStack
cs.DC hep-lat hep-ph
We present a new environment for computations in particle physics
phenomenology employing recent developments in cloud computing. On this
environment users can create and manage "virtual" machines on which the
phenomenology codes/tools can be deployed easily in an automated way. We
analyze the performance of this environment based on "virtual" machines versus
the utilization of "real" physical hardware. In this way we provide a
qualitative result for the influence of the host operating system on the
performance of a representative set of applications for phenomenology
calculations.
| arxiv topic:cs.DC hep-lat hep-ph |
arxiv_dataset-39451212.4884 | Detectability of Earth-like Planets in Circumstellar Habitable Zones of
Binary Star Systems with Sun-like Components
astro-ph.EP astro-ph.IM
Given the considerable percentage of stars that are members of binaries or
stellar multiples in the Solar neighborhood, it is expected that many of these
binaries host planets, possibly even habitable ones. The discovery of a
terrestrial planet in the alpha Centauri system supports this notion. Due to
the potentially strong gravitational interaction that an Earth-like planet may
experience in such systems, classical approaches to determining habitable
zones, especially in close S-Type binary systems, can be rather inaccurate.
Recent progress in this field, however, allows to identify regions around the
star permitting permanent habitability. While the discovery of alpha Cen Bb has
shown that terrestrial planets can be detected in solar-type binary stars using
current observational facilities, it remains to be shown whether this is also
the case for Earth analogues in habitable zones. We provide analytical
expressions for the maximum and RMS values of radial velocity and astrometric
signals, as well as transit probabilities of terrestrial planets in such
systems, showing that the dynamical interaction of the second star with the
planet may indeed facilitate the planets detection. As an example, we discuss
the detectability of additional Earth-like planets in the averaged, extended,
and permanent habitable zones around both stars of the alpha Centauri system.
| arxiv topic:astro-ph.EP astro-ph.IM |
arxiv_dataset-39461212.4984 | On the distribution of stable de Sitter vacua
hep-th
The possible existence of (meta-) stable de Sitter vacua in string theory is
of fundamental importance. So far, there are no fully stable solutions where
all effects are under perturbative control. In this paper we investigate the
presence of stable de Sitter vacua in type II string theory with non-geometric
fluxes. We introduce a systematic method for solving the equations of motion at
the origin of moduli space, by expressing the fluxes in terms of the
supersymmetry breaking parameters. As a particular example, we revisit the
geometric type IIA compactifications, and argue that non-geometric fluxes are
necessary to have (isotropically) stable de Sitter solutions. We also analyse a
class of type II compactifications with non-geometric fluxes, and study the
distribution of (isotropically) stable de Sitter points in the parameter space.
We do this through a random scan as well as through a complementary analysis of
two-dimensional slices of the parameter space. We find that the (isotropically)
stable de Sitter vacua are surprisingly rare, and organise themselves into thin
sheets at small values of the cosmological constant.
| arxiv topic:hep-th |
arxiv_dataset-39471212.5084 | Theoretical aspects of asteroseismology: small steps towards a golden
future
astro-ph.SR
The current status of asteroseismic studies is here reviewed and the adequate
techniques of analysis available today for the study of the oscillation
frequencies are presented. Comments on prospects for future investigations
through the possibility of getting ever more precise asteroseismic observations
from ground and space are given.
| arxiv topic:astro-ph.SR |
arxiv_dataset-39481212.5184 | Stability analysis of chromo-natural inflation and possible evasion of
Lyth's bound
astro-ph.CO gr-qc hep-th
We perform the complete stability study of the model of chromo-natural
inflation (Adshead and Wyman '12), where, due to its coupling to a SU(2)
vector, a pseudo-scalar inflaton chi slowly rolls on a steep potential. As a
typical example, one can consider an axion with a sub-Planckian decay constant
f. The phenomenology of the model was recently studied (Dimastrogiovanni,
Fasiello, and Tolley '12) in the m_g >> H limit, where m_g is the mass of the
fluctuations of the vector field, and H the Hubble rate. We show that the
inflationary solution is stable for m_g > 2 H, while it otherwise experiences a
strong instability due to scalar perturbations in the sub-horizon regime. The
tensor perturbations are instead standard, and the vector ones remain
perturbatively small. Depending on the parameters, this model can give a
gravity wave signal that can be detected in ongoing or forthcoming CMB
experiments. This detection can occur even if, during inflation, the inflaton
spans an interval of size Delta chi = O (f) which is some orders of magnitude
below the Planck scale, evading a well known bound that holds for a free
inflaton (Lyth '97).
| arxiv topic:astro-ph.CO gr-qc hep-th |
arxiv_dataset-39491212.5284 | Dual-Based Bounds for Resource Allocation in Zero-forcing Beamforming
OFDMA-SDMA Systems
cs.IT math.IT
We consider multi-antenna base stations using orthogonal frequency division
multiple access and space division multiple access techniques to serve
single-antenna users. Some users, called real-time users, have minimum rate
requirements and must be served in the current time slot while others, called
non real-time users, do not have strict timing constraints and are served on a
best-effort basis. The resource allocation problem is to find the assignment of
users to subcarriers and the transmit beamforming vectors that maximize the
total user rates subject to power and minimum rate constraints. In general,
this is a nonlinear and non-convex program and the zero-forcing technique used
here makes it integer as well, exact optimal solutions cannot be computed in
reasonable time for realistic cases. For this reason, we present a technique to
compute both upper and lower bounds and show that these are quite close for
some realistic cases.
First, we formulate the dual problem whose optimum provides an upper bound to
all feasible solutions. We then use a simple method to get a primal-feasible
point starting from the dual optimal solution, which is a lower bound on the
primal optimal solution. Numerical results for several cases show that the two
bounds are close so that the dual method can be used to benchmark any heuristic
used to solve this problem. As an example, we provide numerical results showing
the performance gap of the well-known weight adjustment method and show that
there is considerable room for improvement.
| arxiv topic:cs.IT math.IT |
arxiv_dataset-39501212.5384 | Intranight Optical Variability of Radio-Quiet Weak Emission Line Quasars
astro-ph.CO
Based on a recently started programme, we report the first search for
intranight optical variability among radio-quiet weak-line-quasars (RQWLQs).
Eight members of this class were observed on 13 nights in the R-band, such that
each source was monitored continuously at least once for a minimum duration of
about 3.5 hours, using the recently installed 130 cm telescope at Devasthal,
India. Statistical analysis of the differential light curves was carried out
using two versions of the F-test. Based on the INOV data acquired so far, the
radio-quiet WLQ population appears to exhibit stronger INOV activity as
compared to the general population of radio-quiet quasars (RQQs), but similar
to the INOV known for radio-loud quasars of non-blazar type. To improve upon
this early result, as well as extend the comparison to blazars, a factor of ?2
improvement in the INOV detection threshold would be needed. Such efforts are
underway, motivated by the objective to search for the elusive radio-quiet
blazars using INOV observations.
| arxiv topic:astro-ph.CO |
arxiv_dataset-39511212.5484 | Brian\c{c}on-Speder examples and the failure of weak Whitney regularity
math.AG math.CV
It is easy to find real algebraic varieties with weakly Whitney regular
stratifications which are not Whitney regular, and we give such an example in
section 3 below. No examples are known among complex analytic varieties
however, so that the natural question arises : do Whitney regularity and weak
Whitney regularity coincide in the complex case ? As a test, in this paper we
study the well-known Brian\c{c}on-Speder examples.
We investigate systematically all of the (infinitely many)
Brian\c{c}on-Speder examples, and establish in particular that none of these
examples are weakly Whitney regular. We determine all the complex curves along
which Whitney regularity fails and all the complex curves along which weak
Whitney regularity fails. It turns out that for each example there are a finite
number of curves $\gamma_i$ such that weak Whitney regularity fails precisely
along those curves tangent to one of the $\gamma_i$ at the origin.
| arxiv topic:math.AG math.CV |
arxiv_dataset-39521212.5584 | Feshbach resonances, weakly bound molecular states and coupled-channel
potentials for cesium at high magnetic fields
cond-mat.quant-gas physics.atom-ph
We explore the scattering properties of ultracold ground-state Cs atoms at
magnetic fields between 450 G (45 mT) and 1000 G. We identify 17 new Feshbach
resonances, including two very broad ones near 549 G and 787 G. We measure the
binding energies of several different dimer states by magnetic field modulation
spectroscopy. We use least-squares fitting to these experimental results,
together with previous measurements at lower field, to determine a new
6-parameter model of the long-range interaction potential, designated M2012.
Coupled-channels calculations using M2012 provide an accurate mapping between
the s-wave scattering length and the magnetic field over the entire range of
fields considered. This mapping is crucial for experiments that rely on precise
tuning of the scattering length, such as those on Efimov physics.
| arxiv topic:cond-mat.quant-gas physics.atom-ph |
arxiv_dataset-39531212.5684 | Study of some semi-linear elliptic equation
math.AP
We propose in this paper to study the solutions of some nonlinear elliptic
equations with singular potential.
| arxiv topic:math.AP |
arxiv_dataset-39541212.5784 | Hierarchical cascade model leading to 7-th order initial value problem
math.NA physics.flu-dyn
In turbulent flows, local velocity differences often obey a cascade-like
hierarchical dynamics, in the sense that local velocity differences at a given
scale k are driven by deterministic and random forces from the next-higher
scale k-1. Here we consider such a hierarchically coupled model with periodic
boundary conditions, and show that it leads to an N-th order initial value
problem, where N is the number of cascade steps. We deal in detail with the
case N=7 and introduce a non-polynomial spline method that solves the problem
for arbitrary driving forces. Several examples of driving forces are
considered, and estimates of the numerical precision of our method are given.
We show how to optimize the numerical method to obtain a truncation error of
order O(h^5) rather than O(h^2), where h is the discretization step.
| arxiv topic:math.NA physics.flu-dyn |
arxiv_dataset-39551212.5884 | On Jaconian Kummer surfaces
math.AG
We give explicit equations of smooth Jacobian Kummer surfaces of degree 8 by
theta functions. As byproducts, we can write down Rosenhain's 80 hyperpanes and
32 lines on these Kummer surfaces explicitly.
| arxiv topic:math.AG |
arxiv_dataset-39561212.5984 | Disorder induced localization and enhancement of entanglement in one-
and two-dimensional quantum walks
quant-ph cond-mat.dis-nn cond-mat.other
The time evolution of one- and two-dimensional discrete-time quantum walk
with increase in disorder is studied. We use spatial, temporal and
spatio-temporal broken periodicity of the unitary evolution as disorder to
mimic the effect of disordered/random medium in our study. Disorder induces a
dramatic change in the interference pattern leading to localization of the
quantum walks in one- and two-dimensions. Spatial disorder results in the
decreases of the particle and position entanglement in one-dimension and
counter intuitively, an enhancement in entanglement with temporal and
spatio-temporal disorder is seen. The study signifies that the Anderson
localization of quantum state without compromising on the degree of
entanglement could be implement in a large variety of physical settings where
quantum walks has been realized. The study presented here could make it
feasible to explore, theoretically and experimentally the interplay between
disorder and entanglement. This also brings up a variety of intriguing
questions relating to the negative and positive implications on algorithmic and
other applications.
| arxiv topic:quant-ph cond-mat.dis-nn cond-mat.other |
arxiv_dataset-39571212.6084 | Ion-cyclotron Resonance with Streaming Bi-Maxwellian Distribution
astro-ph.SR
We investigate the effect of bulk velocity of the solar wind on the
propagation characteristics of ion-cyclotron waves (ICWs). Our model is based
on the kinetic theory. We solve the Vlasov equation for O VI ions and obtain
the dispersion relation of ICWs. Refractive index of the medium for a streaming
bi-Maxwellian velocity distribution proved to be higher than that of the
bi-Maxwellian velocity distribution. The bulk velocity of the solar polar
coronal holes' plasma increases the value of the refractive index by a factor
of 1.5 (3) when the residual contribution is included (neglected). The ratio of
the refractive index of interplume lanes to the plume lanes at the coronal base
is also higher than we found for the bi-Maxwellian velocity distribution, i.e.
$k_{interplume}/k_{plume}=2.5$.
| arxiv topic:astro-ph.SR |
arxiv_dataset-39581212.6184 | From CM-finite to CM-free
math.RT
The aim of this paper is twofold. On one hand, we prove a slight
generalization of the stability for Gorenstein categories in [SWSW] and
[Huang]; and show that the relative Auslander algebra of a CM-finite algebra is
CM-free. On the other hand, we describe the bounded derived category, and the
Gorenstein defect category introduced in [BJO], via Gorenstein-projective
objects; and we show that the Gorenstein defect category of a CM-finite algebra
is triangle-equivalent to the singularity category of its relative Auslander
algebra.
| arxiv topic:math.RT |
arxiv_dataset-39591212.6284 | Manifestation of Random First Order Transition theory in Wigner glasses
cond-mat.stat-mech
We use Brownian dynamics simulations of a binary mixture of highly charged
spherical colloidal particles to illustrate many of the implications of the
Random First Order Transition (RFOT) theory (PRA 40 1045 (1989)), which is the
only theory that provides a unified description of both the statics and
dynamics of the liquid to glass transition. In accord with the RFOT, we find
that as the volume fraction of the colloidal particles \f, the natural variable
that controls glass formation in colloidal systems, approaches \f_A there is an
effective ergodic to non-ergodic dynamical transition, which is signalled by a
dramatic slowing down of diffusion. In addition, using the energy metric we
show that the system becomes non-ergodic as \f_A is approached. The time t^*,
at which the four-point dynamical susceptibility achieves a maximum, also
diverges near \f_A. Remarkably, three independent measures(translational
diffusion coefficients, ergodic diffusion coefficients,as well t^*) all signal
that at \f_A=0.1 ergodicity is effectively broken. The translation diffusion
constant, the ergodic diffusion constant, and (t^*)^-1 all vanish as
(\f_A-\f)^g with both \f_A and g being the roughly the same for all three
quantities. Below \f_A transport involves crossing suitable free energy
barriers. In this regime, the density-density correlation function decays as a
stretched exponential exp(-t/tau_a)^b with b=0.45. The \f-dependence of the
relaxation time \tau_a is well fit using the VFT law with the ideal glass
transition occurring at \f_K=0.47. By using an approximate measure of the local
entropy (s_3) we show that below \f_A the law of large numbers, which states
that the distribution of s_3 for a large subsample should be identical to the
whole sample, is not obeyed. The comprehensive analyses provided here for
Wigner glass forming charged colloidal suspensions fully validate the concepts
of the RFOT.
| arxiv topic:cond-mat.stat-mech |
arxiv_dataset-39601212.6384 | Crossover from weak to strong disorder regime in the duration of
epidemics
physics.soc-ph q-bio.PE
We study the Susceptible-Infected-Recovered model in complex networks,
considering that not all individuals in the population interact in the same way
between them. This heterogeneity between contacts is modeled by a continuous
disorder. In our model the disorder represents the contact time or the
closeness between individuals. We find that the duration time of an epidemic
has a crossover with the system size, from a power law regime to a logarithmic
regime depending on the transmissibility related to the strength of the
disorder. Using percolation theory, we find that the duration of the epidemic
scales as the average length of the branches of the infection. Our theoretical
findings, supported by simulations, explains the crossover between the two
regimes.
| arxiv topic:physics.soc-ph q-bio.PE |
arxiv_dataset-39611212.6484 | Ward identities for extended objects
cond-mat.supr-con cond-mat.str-el
Ward identities for extended objects are discussed. In the limit of dc
transport it is rigorously proved that charge-density and spin-density
fluctuations do not couple to electromagnetic field.
| arxiv topic:cond-mat.supr-con cond-mat.str-el |
arxiv_dataset-39621212.6584 | The winning property of mixed badly approximable numbers
math.NT
For any pair of real numbers $(i,j)$ with $0<i,j<1$ and $i+j=1$, we prove
that the set of $p$-adic mixed $(i,j)$-badly approximable numbers $\bad_p(i,
j)$ is 1/2-winning in the sense of Schmidt's game. This improves a recent
result of Badziahin, Levesley, and Velani on mixed Schmidt conjecture.
| arxiv topic:math.NT |
arxiv_dataset-39631212.6684 | Waves in Honeycomb Structures
nlin.PS cond-mat.mes-hall math-ph math.AP math.MP quant-ph
We review recent work of the authors on the non-relativistic Schr\"odinger
equation with a honeycomb lattice potential, $V$. In particular, we summarize
results on (i) the existence of Dirac points, conical singularities in
dispersion surfaces of $H_V=-\Delta+V$ and (ii) the two-dimensional Dirac
equations, as a large, but finite time, effective description of
$e^{-iH_Vt}\psi_0$, for data $\psi_0$, which is spectrally localized at a Dirac
point. We conclude with a formal derivation and discussion of the effective
large time evolution for the nonlinear Schr\"odinger - Gross Pitaevskii
equation for small amplitude initial conditions, $\psi_0$. The effective
dynamics are governed by a nonlinear Dirac system.
| arxiv topic:nlin.PS cond-mat.mes-hall math-ph math.AP math.MP quant-ph |
arxiv_dataset-39641212.6784 | On Quantization, the Generalized Schr\"odinger Equation and Classical
Mechanics
quant-ph math-ph math.MP nlin.CD
Using a new state-dependent, $\lambda$-deformable, linear functional
operator, ${\cal Q}_{\psi}^{\lambda}$, which presents a natural $C^{\infty}$
deformation of quantization, we obtain a uniquely selected non--linear,
integro--differential Generalized Schr\"odinger equation. The case ${\cal
Q}_{\psi}^{1}$ reproduces linear quantum mechanics, whereas ${\cal
Q}_{\psi}^{0}$ admits an exact dynamic, energetic and measurement theoretic
{\em reproduction} of classical mechanics. All solutions to the resulting
classical wave equation are given and we show that functionally chaotic
dynamics exists.
| arxiv topic:quant-ph math-ph math.MP nlin.CD |
arxiv_dataset-39651212.6884 | Quantum phase transition in an atom-molecule conversion system with
atomic hopping
cond-mat.quant-gas
The quantum phase transition in an atom-molecule conversion system with
atomic hopping between different hyperfine states is studied. In mean field
approximation, we give the phase diagram whose phase boundary only depends on
the atomic hopping strength and the atom-molecule energy detuning but not on
the atomic interaction. Such a phase boundary is further confirmed by the
fidelity of the ground state and the energy gap between the first-excited state
and the ground one. In comparison to mean field approximation, we also study
the quantum phase transition in full quantum method, where the phase boundary
can be affected by the particle number of the system. Whereas, with the help of
finite-size scaling behaviors of energy gap, fidelity susceptibility and the
first-order derivative of entanglement entropy, we show that one can obtain the
same phase boundary by the MFA and full quantum methods in the limit of
$N\rightarrow \infty$. Additionally, our results show that the quantum phase
transition can happens at the critical value of the atomic hopping strength
even if the atom-molecule energy detuning is fixed on a certain value, which
provides one a new way to control the quantum phase transition.
| arxiv topic:cond-mat.quant-gas |
arxiv_dataset-39661301.001 | The intergalactic Newtonian gravitational field and the shell theorem
astro-ph.CO
The release of the 2MASS Redshift Survey (2MRS), with it's 44599 galaxies
allows the deduction of the galaxy's masses in nearly complete sample. A cubic
box with side of 37 Mpc containing 2429 galaxies is extracted and the Newtonian
gravitational field is evaluated both at the center of the box as well in 101 x
101 x 101 grid points of the box. The obtained results are then discussed at
the light of the shell theorem which states that at the internal of a sphere
the gravitational field is zero.
| arxiv topic:astro-ph.CO |
arxiv_dataset-39671301.011 | Effective complex permittivity tensor of a periodic array of cylinders
cond-mat.mtrl-sci math-ph math.AP math.MP physics.optics
We determine the effective complex permittivity of a two-dimensional
composite, consisting of an arbitrary doubly periodic array of identical
circular cylinders in a homogeneous matrix, and whose dielectric properties are
complex-valued. Efficient formulas are provided to determine the effective
complex permittivity tensor which are in excellent agreement with numerical
calculations. We also show that in contrast to the real-valued case, the real
and imaginary parts of the effective complex-valued tensor can exhibit
non-monotonic behavior as functions of volume fraction of cylinders, and can be
either greater or less than that of the constituents.
| arxiv topic:cond-mat.mtrl-sci math-ph math.AP math.MP physics.optics |
arxiv_dataset-39681301.021 | Central charges and RG flow of strongly-coupled N=2 theory
hep-th
We calculate the central charges a, c and k_G of a large class of
four-dimensional N=2 superconformal field theories arising from compactifying
the six-dimensional N=(2,0) theory on a Riemann surface with regular and
irregular punctures. We also study the renormalization group flows between the
general Argyres-Douglas theories, which all agree with the a-theorem.
| arxiv topic:hep-th |
arxiv_dataset-39691301.031 | Coexistence of fraternity and egoism for spatial social dilemmas
physics.soc-ph q-bio.PE
We have studied an evolutionary game with spatially arranged players who can
choose one of the two strategies (named cooperation and defection for social
dilemmas) when playing with their neighbors. In addition to the application of
the usual strategies in the present model the players are also characterized by
one of the two extreme personal features representing the egoist or fraternal
behavior. During the evolution each player can modify both her own strategy
and/or personal feature via a myopic update process in order to improve her
utility. The results of numerical simulations and stability analysis are
summarized in phase diagrams representing a wide scale of spatially ordered
distribution of strategies and personal features when varying the payoff
parameters. In most of the cases only two of the four possible options prevail
and may form sublattice ordered spatial structure. The evolutionary advantage
of the fraternal attitude is demonstrated within a large range of payoff
parameters including the region of prisoner's dilemma where egoist defectors
and fraternal cooperators form a role-separating chessboard-like pattern.
| arxiv topic:physics.soc-ph q-bio.PE |
arxiv_dataset-39701301.041 | X-Shooter spectroscopy of FU Tau A
astro-ph.SR
We have analyzed a broad-band optical and near-infrared spectrum of FU Tau A,
a presumed young brown dwarf in the Taurus star forming region that has
intrigued both theorists and observers by its over-luminosity in the HR diagram
with respect to standard pre-main sequence evolutionary models. The new data,
obtained with the X-Shooter spectrograph at the Very Large Telescope, include
an unprecedented wealth of information on stellar parameters and simultaneously
observed accretion and outflow indicators for FU Tau A. We present the first
measurements of gravity (log g = 3.5 +- 0.5), radial velocity (RV = 22.5 +- 2.9
km/s), rotational velocity (v sin(i) = 20 +- 5 km/s) and lithium equivalent
width (W_Li = 430 +- 20 mAA) for FUTau A. From the rotational velocity and the
published period we infer a disk inclination of i ~ 50^deg. The lithium content
is much lower than theoretically expected for such a young very low mass
object, adding another puzzling feature to this object's properties. We
determine the mass accretion rate of FU Tau A from comparison of the
luminosities of 24 emission lines to empirical calibrations from the literature
and find a mean of log (dM/dt)_acc [M_sun/yr] = -9.9 +- 0.2. The accretion rate
determined independently from modeling of the excess emission in the Balmer and
Paschen continua is consistent with this value. The corresponding accretion
luminosity is too small to make a significant contribution to the bolometric
luminosity. The existence of an outflow in FU Tau A is demonstrated through the
first detection of forbidden emission lines from which we obtain an estimate
for the mass loss rate, log (dM/dt)_out [M_sun/yr] < -10.4. The mass outflow
and inflow rates can be combined to yield (dM/dt)_out / (dM/dt)_acc ~ 0.3, a
value that is in agreement with jet launching models.
| arxiv topic:astro-ph.SR |
arxiv_dataset-39711301.051 | Partial classification of the Baumslag-Solitar group von Neumann
algebras
math.OA math.GR
We prove that the rational number |n/m| is an invariant of the group von
Neumann algebra of the Baumslag-Solitar group BS(n,m). More precisely, if
L(BS(n,m)) is isomorphic with L(\BS(n',m')), then |n'/m'| = |n/m| or |m/n|. We
obtain this result by associating to abelian, but not maximal abelian,
subalgebras of a II_1 factor, an equivalence relation that can be of type III.
In particular, we associate to L(BS(n,m)) a canonical equivalence relation of
type III_|n/m|.
| arxiv topic:math.OA math.GR |
arxiv_dataset-39721301.061 | A New Class of Upper Bounds on the Log Partition Function
cs.LG stat.ML
Bounds on the log partition function are important in a variety of contexts,
including approximate inference, model fitting, decision theory, and large
deviations analysis. We introduce a new class of upper bounds on the log
partition function, based on convex combinations of distributions in the
exponential domain, that is applicable to an arbitrary undirected graphical
model. In the special case of convex combinations of tree-structured
distributions, we obtain a family of variational problems, similar to the Bethe
free energy, but distinguished by the following desirable properties: i. they
are cnvex, and have a unique global minimum; and ii. the global minimum gives
an upper bound on the log partition function. The global minimum is defined by
stationary conditions very similar to those defining fixed points of belief
propagation or tree-based reparameterization Wainwright et al., 2001. As with
BP fixed points, the elements of the minimizing argument can be used as
approximations to the marginals of the original model. The analysis described
here can be extended to structures of higher treewidth e.g., hypertrees,
thereby making connections with more advanced approximations e.g., Kikuchi and
variants Yedidia et al., 2001; Minka, 2001.
| arxiv topic:cs.LG stat.ML |
arxiv_dataset-39731301.071 | H\"older continuous solutions to complex Hessian equations
math.CV
We prove the H\"older continuity of the solution to complex Hessian equation
with the right hand side in $L^p$, $p>\frac{n}{m}$, $1< m< n$, in a
$m$-strongly pseudoconvex domain in $\mathbb{C}^n$ under some additional
conditions on the density near the boundary and on the boundary data.
| arxiv topic:math.CV |
arxiv_dataset-39741301.081 | Relations between the convexity of a set and the differentiability of
its support function
math.FA
It is known that, in finite dimensions, the support function of a compact
convex set with non empty interior is differentiable excepting the origin if
and only if the set is strictly convex. In this paper we realize a thorough
study of the relations between the differentiability of the support function on
the interior of its domain and the convexity of the set, mainly for unbounded
sets. Then we revisit some results related to the differentiability of the cost
function associated to a production function.
| arxiv topic:math.FA |
arxiv_dataset-39751301.091 | Generalized derivations and general relativity
gr-qc math-ph math.MP
We construct differential geometry (connection, curvature, etc.) based on
generalized derivations of an algebra ${\cal A}$. Such a derivation, introduced
by Bresar in 1991, is given by a linear mapping $u: {\cal A} \rightarrow {\cal
A}$ such that there exists a usual derivation $d$ of ${\cal A}$ satisfying the
generalized Leibniz rule $u(a b) = u(a) b + a \, d(b)$ for all $a,b \in \cal
A$. The generalized geometry "is tested" in the case of the algebra of smooth
functions on a manifold. We then apply this machinery to study generalized
general relativity. We define the Einstein-Hilbert action and deduce from it
Einstein's field equations. We show that for a special class of metrics
containing, besides the usual metric components, only one nonzero term, the
action reduces to the O'Hanlon action that is the Brans-Dicke action with
potential and with the parameter $\omega$ equal to zero. We also show that the
generalized Einstein equations (with zero energy-stress tensor) are equivalent
to those of the Kaluza-Klein theory satisfying a "modified cylinder condition"
and having a noncompact extra dimension. This opens a possibility to consider
Kaluza-Klein models with a noncompact extra dimension that remains invisible
for a macroscopic observer. In our approach, this extra dimension is not an
additional physical space-time dimension but appears because of the
generalization of the derivation concept.
| arxiv topic:gr-qc math-ph math.MP |
arxiv_dataset-39761301.101 | Coupling between time series: a network view
physics.data-an physics.soc-ph q-fin.ST
Recently, the visibility graph has been introduced as a novel view for
analyzing time series, which maps it to a complex network. In this paper, we
introduce new algorithm of visibility, "cross-visibility", which reveals the
conjugation of two coupled time series. The correspondence between the two time
series is mapped to a network, "the cross-visibility graph", to demonstrate the
correlation between them. We applied the algorithm to several correlated and
uncorrelated time series, generated by the linear stationary ARFIMA process.
The results demonstrate that the cross-visibility graph associated with
correlated time series with power-law auto-correlation is scale-free. If the
time series are uncorrelated, the degree distribution of their cross-visibility
network deviates from power-law. For more clarifying the process, we applied
the algorithm to real-world data from the financial trades of two companies,
and observed significant small-scale coupling in their dynamics.
| arxiv topic:physics.data-an physics.soc-ph q-fin.ST |
arxiv_dataset-39771301.111 | Casimir expulsion of shifted configurations
quant-ph
The shift of nanosized metal configurations relative to one another can lead
to an increase in the range of optimal lengths of wings and angles of the
opening of cavities, at which noncompensated Casimir forces in them are
maximal. The possibility of the existence of the effect of Casimir expulsion is
demonstrated with a trapezoid cavity with shifted wings which are opened at
different angles. It is also shown that shift in parallel structures leads to
the appearance of forces tending to bring the configuration back to the
situation before the shift. In some conditions, in systems with shifted
structures there are moments of torsion and complex oscillation processes.
| arxiv topic:quant-ph |
arxiv_dataset-39781301.121 | Spectral estimates on the sphere
math.AP
In this article we establish optimal estimates for the first eigenvalue of
Schr\"odinger operators on the d-dimensional unit sphere. These estimates
depend on Lebsgue's norms of the potential, or of its inverse, and are
equivalent to interpolation inequalities on the sphere. We also characterize a
semi-classical asymptotic regime and discuss how our estimates on the sphere
differ from those on the Euclidean space.
| arxiv topic:math.AP |
arxiv_dataset-39791301.131 | Micro-tearing modes in spherical and conventional tokamaks
physics.plasm-ph
The onset and characteristics of Micro-Tearing Modes (MTM) in the core of
spherical (NSTX) and conventional tokamaks (ASDEX-UG and JET) are studied
through local linear gyrokinetic simulations with gyro [J. Candy and E. Belli,
General Atomics Report GA-A26818 (2011)]. For experimentally relevant core
plasma parameters in the NSTX and ASDEX-UG tokamaks, in agreement with previous
works, we find MTMs as the dominant linear instability. Also, for JET-like core
parameters considered in our study an MTM is found as the most unstable mode.
In all these plasmas, finite collisionality is needed for MTMs to become
unstable and the electron temperature gradient is found to be the fundamental
drive. However, a significant difference is observed in the dependence of
linear growth rate of MTMs on electron temperature gradient. While it varies
weakly and non-monotonically in JET and ASDEX-UG plasmas, in NSTX it increases
with the electron temperature gradient.
| arxiv topic:physics.plasm-ph |
arxiv_dataset-39801301.141 | Review on top forward-backward asymmetry
hep-ph hep-ex
The top forward-backward asymmetry (FBA) observed at the Tevatron has been a
hot issue in particle physics for the last few years. In this talk, I describe
two different approaches for the top FBA at the Tevatron, one in effective
field theory (EFT) approach and the other in explicit model for $Z'$. Within
the first approach, I identify a class of models which can accommodate the top
FBA when new physics scale is very heavy. Axigluon or $t$-channel scalar
exchanges with flavor dependent couplings can do the job. In the second
approach, I show that the chiral couplings of $Z'$ necessarily invites multi
Higgs doublets with $Z'$ couplings. Otherwise the top quark becomes massless,
which is completely unphysical. Newly introduced multi Higgs doublets also
contribute to the top FBA, $\sigma_{tt}$ and the charge asymmetry at the LHC,
and there are parameter regions which are compatible with all the observations
related with the top quarks.
| arxiv topic:hep-ph hep-ex |
arxiv_dataset-39811301.151 | INPOP new release: INPOP10e
astro-ph.EP
The INPOP ephemerides have known several improvements and evolutions since
the first INPOP06 release (Fienga et al. 2008) in 2008. In 2010, anticipating
the IAU 2012 resolutions, adjustement of the gravitational solar mass with a
fixed astronomical unit (AU) has been for the first time implemented in
INPOP10a (Fienga et al. 2011) together with improvements in the asteroid mass
determinations. With the latest INPOP10e version, such advancements have been
enhanced and studies about solar corona have also been investigated (Verma et
al. 2012). The use of planetary ephemerides for several physical applications
are presented here from electronic densities of solar slow and fast winds to
asteroid mass determinations and tests of general relativity operated with
INPOP10a. Perspectives will also be drawn especially related to the analysis of
the Messenger spacecraft data for the planetary orbits and future computation
of the time variations of the gravitational mass of the sun.
| arxiv topic:astro-ph.EP |
arxiv_dataset-39821301.161 | Two Distinct Phases of Bilayer Graphene Films on Ru(0001)
cond-mat.mes-hall cond-mat.mtrl-sci
By combining angle-resolved photoemission spectroscopy and scanning tunneling
microscopy we reveal the structural and electronic properties of multilayer
graphene on Ru(0001). We prove that large ethylene exposure allows to
synthesize two distinct phases of bilayer graphene with different properties.
The first phase has Bernal AB stacking with respect to the first graphene
layer, displays weak vertical interaction and electron doping. The long-range
ordered moir\'e pattern modulates the crystal potential and induces replicas of
the Dirac cone and minigaps. The second phase has AA stacking sequence with
respect to the first layer, displays weak structural and electronic modulation
and p-doping. The linearly dispersing Dirac state reveals the
nearly-freestanding character of this novel second layer phase.
| arxiv topic:cond-mat.mes-hall cond-mat.mtrl-sci |
arxiv_dataset-39831301.171 | Evolutionary Exploration of the Finitely Repeated Prisoners'
Dilemma--The Effect of Out-of-Equilibrium Play
q-bio.PE cs.GT
The finitely repeated Prisoners' Dilemma is a good illustration of the
discrepancy between the strategic behaviour suggested by a game-theoretic
analysis and the behaviour often observed among human players, where
cooperation is maintained through most of the game. A game-theoretic reasoning
based on backward induction eliminates strategies step by step until defection
from the first round is the only remaining choice, reflecting the Nash
equilibrium of the game. We investigate the Nash equilibrium solution for two
different sets of strategies in an evolutionary context, using
replicator-mutation dynamics. The first set consists of conditional
cooperators, up to a certain round, while the second set in addition to these
contains two strategy types that react differently on the first round action:
The "Convincer" strategies insist with two rounds of initial cooperation,
trying to establish more cooperative play in the game, while the "Follower"
strategies, although being first round defectors, have the capability to
respond to an invite in the first round. For both of these strategy sets,
iterated elimination of strategies shows that the only Nash equilibria are
given by defection from the first round. We show that the evolutionary dynamics
of the first set is always characterised by a stable fixed point, corresponding
to the Nash equilibrium, if the mutation rate is sufficiently small (but still
positive). The second strategy set is numerically investigated, and we find
that there are regions of parameter space where fixed points become unstable
and the dynamics exhibits cycles of different strategy compositions. The
results indicate that, even in the limit of very small mutation rate, the
replicator-mutation dynamics does not necessarily bring the system with
Convincers and Followers to the fixed point corresponding to the Nash
equilibrium of the game.
| arxiv topic:q-bio.PE cs.GT |
arxiv_dataset-39841301.181 | Forcing-dependent stability of steady states in a turbulent swirling
flow
physics.flu-dyn nlin.CD
We study the influence of the forcing on the steady turbulent states of a von
K\'arm\'an swirling flow, at constant impeller speed, or at constant torque. We
find that the different forcing conditions change the nature of the stability
of the steady states and reveal dynamical regimes that bear similarities with
low-dimensional systems. We suggest that this forcing dependence may be an out-
of-equilibrium analogue of the ensemble inequivalence, valid for long-range
interacting statistical systems, and that it may be applicable to other
turbulent systems.
| arxiv topic:physics.flu-dyn nlin.CD |
arxiv_dataset-39851301.191 | A QCD description of the ATLAS jet veto measurement
hep-ph
We present a new QCD description of the ATLAS jet veto measurement, using the
Banfi-Marchesini-Smye equation to constrain the inter-jet QCD radiation. This
equation resums emissions of soft gluons at large angles, at
leading-logarithmic accuracy, and accounts for both the so-called Sudakov and
non-global logarithms. We show that this approach is able to reproduce, with no
fitting parameters, the fraction of high-pT forward/backward di-jet events
which do not contain additional hard emissions in the inter-jet rapidity range.
We also compute the gap fraction in fixed-order perturbation theory to
O(alpha_s^2) and show that the perturbative series is unstable at large
rapidity intervals.
| arxiv topic:hep-ph |
arxiv_dataset-39861301.201 | Authentication Schemes Using Polynomials Over Non-Commutative Rings
cs.CR math.RA
Authentication is a process by which an entity,which could be a person or
intended computer,establishes its identity to another entity.In private and
public computer networks including the Internet,authentication is commonly done
through the use of logon passwords. Knowledge of the password is assumed to
guarantee that the user is authentic.Internet business and many other
transactions require a more stringent authentication process. The aim of this
paper is to propose two authentication schemes based on general non-commutative
rings. The key idea of the schemes is that for a given non-commutative ring;
one can build polynomials on additive structure and takes them as underlying
work structure. By doing so, one can implement authentication schemes, one of
them being zero-knowledge interactive proofs of knowledge, on multiplicative
structure of the ring. The security of the schemes is based on the
intractability of the polynomial symmetrical decomposition problem over the
given non-commutative ring.
| arxiv topic:cs.CR math.RA |
arxiv_dataset-39871301.211 | Near-Infrared Monitoring and Modelling of V1647 Ori in its On-going
2008-12 Outburst Phase
astro-ph.SR
We present results of Mt Abu JHK photometric and HI Brackett $\gamma$ line
monitoring of the eruptive YSO V1647 Orionis (McNeil's Object) during the
on-going outburst phase in 2008-2012. We discuss JHK colour patterns and
extinction during the outburst and compare these with the previous outburst
phase in 2004-05 and the intervening quiescent period of about 2 years.
Commencing from early 2012, the object shows a slow fading out in all the
bands. We report brightness variations in the nearby Herbig-Haro object HH22
possibly associated with those in V1647 Ori. We also present modelling of the
spectral energy distributions of V1647 Ori during its recent outburst and
quiescent phases. The physical parameters of the protostar and its
circumstellar environment obtained from the modelling indicate marked
differences in the two phases.
| arxiv topic:astro-ph.SR |
arxiv_dataset-39881301.221 | Nanoscale Heat Transfer: from Computation to Experiment
cond-mat.mtrl-sci cond-mat.mes-hall physics.chem-ph
Heat transfer can differ distinctly at the nanoscale from that at the
macroscale. Recent advancement in computational and experimental techniques has
enabled a large number of interesting observations and understanding of heat
transfer processes at the nanoscale. In this review, we will first discuss
recent advances in computational and experimental methods used in nanoscale
thermal transport studies, followed by reviews of novel thermal transport
phenomena at the nanoscale observed in both computational and experimental
studies, and discussion on current understanding of these novel phenomena. Our
perspectives on challenges and opportunities on computational and experimental
methods are also presented.
| arxiv topic:cond-mat.mtrl-sci cond-mat.mes-hall physics.chem-ph |
arxiv_dataset-39891301.231 | Policy Improvement for POMDPs Using Normalized Importance Sampling
cs.AI cs.LG
We present a new method for estimating the expected return of a POMDP from
experience. The method does not assume any knowledge of the POMDP and allows
the experience to be gathered from an arbitrary sequence of policies. The
return is estimated for any new policy of the POMDP. We motivate the estimator
from function-approximation and importance sampling points-of-view and derive
its theoretical properties. Although the estimator is biased, it has low
variance and the bias is often irrelevant when the estimator is used for
pair-wise comparisons. We conclude by extending the estimator to policies with
memory and compare its performance in a greedy search algorithm to REINFORCE
algorithms showing an order of magnitude reduction in the number of trials
required.
| arxiv topic:cs.AI cs.LG |
arxiv_dataset-39901301.241 | Backward-in-Time Selection of the Order of Dynamic Regression Prediction
Model
stat.AP stat.ME stat.ML
We investigate the optimal structure of dynamic regression models used in
multivariate time series prediction and propose a scheme to form the lagged
variable structure called Backward-in-Time Selection (BTS) that takes into
account feedback and multi-collinearity, often present in multivariate time
series. We compare BTS to other known methods, also in conjunction with
regularization techniques used for the estimation of model parameters, namely
principal components, partial least squares and ridge regression estimation.
The predictive efficiency of the different models is assessed by means of Monte
Carlo simulations for different settings of feedback and multi-collinearity.
The results show that BTS has consistently good prediction performance while
other popular methods have varying and often inferior performance. The
prediction performance of BTS was also found the best when tested on human
electroencephalograms of an epileptic seizure, and to the prediction of returns
of indices of world financial markets.
| arxiv topic:stat.AP stat.ME stat.ML |
arxiv_dataset-39911301.251 | Hamiltonian Approach to QCD: The effective potential of the Polyakov
loop
hep-th
The effective potential of the order parameter for confinement is calculated
within the Hamiltonian approach to Yang--Mills theory. Compactifying one
spatial dimension and using a background gauge fixing this potential is
obtained by minimizing the energy density for a given background field. Using
Gaussian type trial wave functionals I establish an analytic relation between
the propagators in the background gauge at finite temperature and the
corresponding zero temperature propagators in Coulomb gauge. In the simplest
truncation, neglecting the ghost and using the ultraviolet form of the gluon
energy one recovers the Weiss potential. From the fully non-perturbative
potential (with the ghost included) one extracts a critical temperature of the
deconfinement phase transition of 270 MeV for the gauge group SU(2).
| arxiv topic:hep-th |
arxiv_dataset-39921301.261 | Detecting Breakage Fusion Bridge cycles in tumor genomes -- an
algorithmic approach
q-bio.GN q-bio.QM
Breakage-Fusion-Bridge (BFB) is a mechanism of genomic instability
characterized by the joining and subsequent tearing apart of sister chromatids.
When this process is repeated during multiple rounds of cell division, it leads
to patterns of copy number increases of chromosomal segments as well as
fold-back inversions where duplicated segments are arranged head-to-head. These
structural variations can then drive tumorigenesis.
BFB can be observed in progress using cytogenetic techniques, but generally
BFB must be inferred from data like microarrays or sequencing collected after
BFB has ceased. Making correct inferences from this data is not
straightforward, particularly given the complexity of some cancer genomes and
BFB's ability to generate a wide range of rearrangement patterns.
Here we present algorithms to aid the interpretation of evidence for BFB. We
first pose the BFB count vector problem: given a chromosome segmentation and
segment copy numbers, decide whether BFB can yield a chromosome with the given
segment counts. We present the first linear-time algorithm for the problem,
improving a previous exponential-time algorithm. We then combine this algorithm
with fold-back inversions to develop tests for BFB. We show that, contingent on
assumptions about cancer genome evolution, count vectors and fold-back
inversions are sufficient evidence for detecting BFB. We apply the presented
techniques to paired-end sequencing data from pancreatic tumors and confirm a
previous finding of BFB as well as identify a new chromosomal region likely
rearranged by BFB cycles, demonstrating the practicality of our approach.
| arxiv topic:q-bio.GN q-bio.QM |
arxiv_dataset-39931301.271 | A High-Order Sliding Mode Observer: Torpedo Guidance Application
cs.SY
The guidance of a torpedo represents a hard task because of the smooth
nonlinear aspect of this system and because of the extreme external
disturbances. The torpedo guidance reposes on the speed and the position
control. In fact, the control approach which is very solicited for the
electromechanical systems is the sliding mode control (SMC) which proved its
effectiveness through the different studies. The SMC is robust versus
disturbances and model uncertainties; however, a sharp discontinuous control is
needed which induces the chattering phenomenon. The angular velocity
measurement is a hard task because of the high level of disturbances. In this
way, the sliding mode observer could be a solution for the velocity estimation
instead of a sensor. This article deals with torpedo guidance by SMC to reach
the desired path in a short time and with high precision quality. Simulation
results show that this control strategy and observer can attain excellent
control performances with no chattering problem.
| arxiv topic:cs.SY |
arxiv_dataset-39941301.281 | Oscillator strengths of the intersubband electronic transitions in the
multi-layered nano-antidots with hydrogenic impurity
cond-mat.mes-hall cond-mat.mtrl-sci
In this study, we have obtained the exact solutions of the Schr\"{o}dinger
equation for a multi-layered quantum antidot (MLQAD) within the effective mass
approximation and dielectric continuum model for the spherical symmetry. The
MLQAD is nano-structured semiconductor system that consists of a spherical core
(e.g. $Ga_{1-x}Al_{x}As $) and a coated spherical shell (e.g. $Ga_{1-y}Al_{y}As
$) as the whole anti-dot is embedded inside a bulk material (e.g. $GaAs $). The
dependence of the electron energy spectrum and its radial probability density
on nano-system radius are studied. The numeric calculations and analysis of
oscillator strength of intersubband quantum transition from the ground state
into two first allowed excited states at the varying radius, for both the
finite and infinite confining potential (CP) as well as constant shell
thickness, are performed. It is shown that, in particular, the binding energy
and the oscillator strength of the hydrogenic impurity of a MLQAD behave
differently from that of a single-layered quantum antidot (SLQAD). For a MLQAD
with finite core and shell CPs, the state energies and the oscillator strengths
of the impurity are found to be dependent on the shell thickness. At the large
core radius and very small shell thickness, our results are closer to
respective values for a SLQAD that previously reported.
| arxiv topic:cond-mat.mes-hall cond-mat.mtrl-sci |
arxiv_dataset-39951301.291 | Generators for a module of vector-valued Siegel modular forms of degree
2
math.AG math.NT
In this paper we will describe all vector-valued Siegel modular forms of
degree 2 and weight ${\rm Sym}^6({\rm St}) \otimes \det^{k}({\rm St})$ with $k$
odd. These vector-valued forms constitute a module over the ring of classical
Siegel modular forms of degree 2 and even weight and this module turns out to
be free. In order to find generators, we generalize certain Rankin-Cohen
differential operators on triples of classical Siegel modular forms that were
first considered by Ibukiyama and we find a Rankin-Cohen bracket on
vector-valued Siegel modular forms.
| arxiv topic:math.AG math.NT |
arxiv_dataset-39961301.301 | A new method to improve photometric redshift reconstruction.
Applications to the Large Synoptic Survey Telescope
astro-ph.CO astro-ph.IM
In the next decade, the LSST will become a major facility for the
astronomical community. However accurately determining the redshifts of the
observed galaxies without using spectroscopy is a major challenge.
Reconstruction of the redshifts with high resolution and well-understood
uncertainties is mandatory for many science goals, including the study of
baryonic acoustic oscillations. We investigate different approaches to
establish the accuracy that can be reached by the LSST six-band photometry. We
construct a realistic mock galaxy catalog, based on the GOODS survey luminosity
function, by simulating the expected apparent magnitude distribution for the
LSST. To reconstruct the photometric redshifts (photo-z's), we consider a
template-fitting method and a neural network method. The photo-z reconstruction
from both of these techniques is tested on real CFHTLS data and also on
simulated catalogs. We describe a new method to improve photo-z reconstruction
that efficiently removes catastrophic outliers via a likelihood ratio
statistical test. This test uses the posterior probability functions of the fit
parameters and the colors. We show that the photometric redshift accuracy will
meet the stringent LSST requirements up to redshift $\sim2.5$ after a selection
that is based on the likelihood ratio test or on the apparent magnitude for
galaxies with $S/N>5$ in at least 5 bands. The former selection has the
advantage of retaining roughly 35% more galaxies for a similar photo-z
performance compared to the latter. Photo-z reconstruction using a neural
network algorithm is also described. In addition, we utilize the CFHTLS
spectro-photometric catalog to outline the possibility of combining the neural
network and template-fitting methods. We conclude that the photo-z's will be
accurately estimated with the LSST if a Bayesian prior probability and a
calibration sample are used.
| arxiv topic:astro-ph.CO astro-ph.IM |
arxiv_dataset-39971301.311 | Week 1 Influenza Forecast for the 2012-2013 U.S. Season
q-bio.PE stat.AP
This is part of a series of weekly influenza forecasts made during the
2012-2013 influenza season. Here we present results of forecasts initiated
following assimilation of observations for Week 1 (i.e. the forecast begins
January 6, 2013) for municipalities in the United States. These forecasts were
performed on January 11, 2013. Results from forecasts initiated the six
previous weeks (Weeks 47-52) are also presented. The accuracy of these
predictions will not be known for certain until the conclusion of the current
influenza season; however, at the moment a number of the forecasted peaks
appear to be inaccurate. This inaccuracy may be due to the virulence of
influenza this season, which appears to be sending more influenza-infected
persons to seek medical attention and inflates ILI levels (and possibly the
proportion testing influenza positive) relative to years with milder flu
strains. New forecasts that adjust, or scale, for this difference and match the
two focus cities that appear to have already peaked are identified. These new
forecasts will be used, in addition to the previously scaled forms, to make
influenza predictions for the remainder of the season.
| arxiv topic:q-bio.PE stat.AP |
arxiv_dataset-39981301.321 | Faster Quantum Number Factoring via Circuit Synthesis
quant-ph cs.DS cs.ET
A major obstacle to implementing Shor's quantum number-factoring algorithm is
the large size of modular-exponentiation circuits. We reduce this bottleneck by
customizing reversible circuits for modular multiplication to individual runs
of Shor's algorithm. Our circuit-synthesis procedure exploits spectral
properties of multiplication operators and constructs optimized circuits from
the traces of the execution of an appropriate GCD algorithm. Empirically, gate
counts are reduced by 4-5 times, and circuit latency is reduced by larger
factors.
| arxiv topic:quant-ph cs.DS cs.ET |
arxiv_dataset-39991301.331 | Specifics of thermodynamic description of nanocrystals
cond-mat.mes-hall cond-mat.mtrl-sci
A method of statistical description of thermodynamic properties of
nanocrystals is developed. It is established that size-dependent quantization
of vibrational modes results in formation of excess pressure of the phonon gas
acting outwards the crystal. Based on the concept of the phonon gas pressure,
size dependence of thermodynamic properties of nanocrystals was described, and
size influence on a shift of a phase transformation temperature was explained.
| arxiv topic:cond-mat.mes-hall cond-mat.mtrl-sci |
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