8,511 research outputs found
Classical quasi-trigonometric matrices of Cremmer-Gervais type and their quantization
We propose a method of quantization of certain Lie bialgebra structures on
the polynomial Lie algebras related to quasi-trigonometric solutions of the
classical Yang-Baxter equation. The method is based on so-called affinization
of certain seaweed algebras and their quantum analogues.Comment: 9 pages, LaTe
Functional renormalization group approach to the singlet-triplet transition in quantum dots
We present a functional renormalization group approach to the zero bias
transport properties of a quantum dot with two different orbitals and in
presence of Hund's coupling. Tuning the energy separation of the orbital
states, the quantum dot can be driven through a singlet-triplet transition. Our
approach, based on the approach by Karrasch {\em et al} which we apply to
spin-dependent interactions, recovers the key characteristics of the quantum
dot transport properties with very little numerical effort. We present results
on the conductance in the vicinity of the transition and compare our results
both with previous numerical renormalization group results and with predictions
of the perturbative renormalization group.Comment: 15 pages, 9 figure
Spin-orbit coupled cold exciton condensates
We analyze theoretically the dynamics of degenerate condensate of cold
indirect excitons. We account for both linear spin dependent terms arising from
spin-orbit interaction of Rashba and Dresselhaus types and non-linear terms
transforming a pair of bright excitons into a pair of dark ones. We show that
both terms should lead to the qualitative changes in the dynamics of cold
exciton droplets in the real space and time.Comment: 14 pages, 7 figure
Density-matrix approach for an interacting polariton system
Using the Lindblad approach we develop a general formalism for theoretical
description of a spatially inhomogeneous bosonic system with dissipation
provided by the interaction of bosons with a phonon bath. We apply our results
to model the dynamics of an interacting one-dimensional polariton system in
real space and time, analyzing in detail the role of polariton-polariton and
polariton-phonon interactions.Comment: 7 pages + 3 figures. arXiv admin note: text overlap with
arXiv:1103.1336 by other author
A shared mechanism of muscle wasting in cancer and Huntington's disease.
Skeletal muscle loss and dysfunction in aging and chronic diseases is one of the major causes of mortality in patients, and is relevant for a wide variety of diseases such as neurodegeneration and cancer. Muscle loss is accompanied by changes in gene expression and metabolism that lead to contractile impairment and likely affect whole-body metabolism and function. The changes may be caused by inactivity, inflammation, age-related factors or unbalanced nutrition. Although links with skeletal muscle loss have been found in diseases with disparate aetiologies, for example both in Huntingtons disease (HD) and cancer cachexia, the outcome is a similar impairment and mortality. This short commentary aims to summarize recent achievements in the identification of common mechanisms leading to the skeletal muscle wasting syndrome seen in diseases as different as cancer and HD. The latter is the most common hereditary neurodegenerative disorder and muscle wasting is an important component of its pathology. In addition, possible therapeutic strategies for anti-cachectic treatment will be also discussed in the light of their translation into possible therapeutic approaches for HD
Bistability phenomena in one-dimensional polariton wires
We investigate the phenomena of bistability and domain wall propagation in
polaritonic systems with dissipation provided by the interaction with
incoherent phonon bath. The results on the temperature dependence of the
polariton bistability behavior and polariton neuron switching are presented.Comment: 6 pages + 4 figures. Continuation of the work published in Phys. Rev.
B 83, 165316 (2011
Phonon-mediated Josephson oscillations in excitonic and polaritonic condensates
We analyze theoretically the role of the exciton-phonon interactions in
phenomena related to the Josephson effect between two spatially separated
exciton and exciton-polariton condensates. We consider the role of the
dephasing introduced by phonons in such phenomena as Josephson tunneling,
self-trapping and spontaneous polarization separation. In the regime of cw
pumping we find a remarkable bistability effect arising from exciton- exciton
interactions as well as regimes of self- sustained regular and chaotic
oscillations.Comment: 10 pages, Submitted to Phys. Rev.
Herding cats: observing live coding in the wild
After a momentous decade of live coding activities, this paper seeks to explore the practice with the aim of situating it in the history of contemporary arts and music. The article introduces several key points of investigation in live coding research and discusses some examples of how live coding practitioners engage with these points in their system design and performances. In the light of the extremely diverse manifestations of live coding activities, the problem of defining the practice is discussed, and the question raised whether live coding will actually be necessary as an independent category
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