27,858 research outputs found
A Comparison Between Different Cycle Decompositions for Metropolis Dynamics
In the last decades the problem of metastability has been attacked on
rigorous grounds via many different approaches and techniques which are briefly reviewed in this paper.
It is then useful to understand connections between different
point of views. In view of this
we consider irreducible, aperiodic and
reversible Markov chains with exponentially
small transition probabilities in the framework of Metropolis dynamics.
We compare two different cycle decompositions and prove their equivalence
Algebras in tensor categories and coset conformal field theories
The coset construction is the most important tool to construct rational
conformal field theories with known chiral data. For some cosets at small
level, so-called maverick cosets, the familiar analysis using selection and
identification rules breaks down. Intriguingly, this phenomenon is linked to
the existence of exceptional modular invariants. Recent progress in CFT, based
on studying algebras in tensor categories, allows for a universal construction
of the chiral data of coset theories which in particular also applies to
maverick cosets.Comment: 6 pages, 3 figures; Proceeding Ahrenshoop 200
Kramers-Wannier duality from conformal defects
We demonstrate that the fusion algebra of conformal defects of a
two-dimensional conformal field theory contains information about the internal
symmetries of the theory and allows one to read off generalisations of
Kramers-Wannier duality. We illustrate the general mechanism in the examples of
the Ising model and the three-states Potts model.Comment: 8 pages, 4 figures; v2: version published in PR
Following basal stem rot in young oil palm plantings
The PCR primer GanET has previously been shown to be suitable for the specific amplification of DNA from Ganoderma boninense. A DNA extraction and PCR method has been developed that allows for the amplification of the G. boninense DNA from environmental samples of oil palm tissue. The GanET primer reaction was used in conjunction with a palm-sampling programme to investigate the possible infection of young palms through cut frond base surfaces. Ganoderma DNA was detected in frond base material at a greater frequency than would be expected by comparison with current infection levels. Comparisons are made between the height of the frond base infected, the number of frond bases infected, and subsequent development of basal stem rot. The preliminary results suggest that the development of basal stem rot may be more likely to occur when young lower frond bases are infected
Learning 3D Navigation Protocols on Touch Interfaces with Cooperative Multi-Agent Reinforcement Learning
Using touch devices to navigate in virtual 3D environments such as computer
assisted design (CAD) models or geographical information systems (GIS) is
inherently difficult for humans, as the 3D operations have to be performed by
the user on a 2D touch surface. This ill-posed problem is classically solved
with a fixed and handcrafted interaction protocol, which must be learned by the
user. We propose to automatically learn a new interaction protocol allowing to
map a 2D user input to 3D actions in virtual environments using reinforcement
learning (RL). A fundamental problem of RL methods is the vast amount of
interactions often required, which are difficult to come by when humans are
involved. To overcome this limitation, we make use of two collaborative agents.
The first agent models the human by learning to perform the 2D finger
trajectories. The second agent acts as the interaction protocol, interpreting
and translating to 3D operations the 2D finger trajectories from the first
agent. We restrict the learned 2D trajectories to be similar to a training set
of collected human gestures by first performing state representation learning,
prior to reinforcement learning. This state representation learning is
addressed by projecting the gestures into a latent space learned by a
variational auto encoder (VAE).Comment: 17 pages, 8 figures. Accepted at The European Conference on Machine
Learning and Principles and Practice of Knowledge Discovery in Databases 2019
(ECMLPKDD 2019
Substituting the main group element in cobalt - iron based Heusler alloys: CoFeAlSi
This work reports about electronic structure calculations for the Heusler
compound CoFeAlSi. Particular emphasis was put on the role of
the main group element in this compound. The substitution of Al by Si leads to
an increase of the number of valence electrons with increasing Si content and
may be seen as electron-doping. Self-consistent electronic structure
calculations were performed to investigate the consequences of the electron
doping for the magnetic properties. The series CoFeAlSi is
found to exhibit half-metallic ferromagnetism and the magnetic moment follows
the Slater-Pauling rule. It is shown that the electron-doping stabilises the
gap in the minority states for .Comment: J. Phys. D (accepted
Current Development and Research in Traditional Chinese Nonpharmacologic Therapy for Pain
published_or_final_versio
Global behavior of cosmological dynamics with interacting Veneziano ghost
In this paper, we shall study the dynamical behavior of the universe
accelerated by the so called Veneziano ghost dark energy component locally and
globally by using the linearization and nullcline method developed in this
paper. The energy density is generalized to be proportional to the Hawking
temperature defined on the trapping horizon instead of Hubble horizon of the
Friedmann-Robertson-Walker (FRW) universe. We also give a prediction of the
fate of the universe and present the bifurcation phenomenon of the dynamical
system of the universe. It seems that the universe could be dominated by dark
energy at present in some region of the parameter space.Comment: 8 pages, 7 figures, accepted for publication in JHE
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