2,075 research outputs found
Golden Ratio Controlled Chaos in Supersymmetric Dynamics
We construct supersymmetric Lagrangians for the recently constructed
off-shell worldline N=3 supermultiplet for I=1,2,3, where
and are standard, Salam-Strathdee superfields: fermionic and
bosonic. Already the Lagrangian bilinear in component fields exhibits a total
of thirteen free parameters, seven of which specify Zeeman-like coupling to
external (magnetic) fluxes. All but special subsets of this parameter space
describe aperiodic oscillatory response, some of which are controlled by the
"golden ratio," . We also show that all of these
Lagrangians admit an supersymmetry extension, while a subset admits
two inequivalent such extensions
An enamel-painted glass bottle from a “Turkish pit” in Buda
The fragments of a high quality, enamel painted, blue glass bottle with the date 1671 on its shoulder were found in the Castle District of Buda, in a huge pit dated to the period of the Ottoman occupation. The shape of the object shows eastern influences, while its decoration is clearly western. The origin of the bottle is probably Transylvanian, based on its characteristics and a small group of parallels
Periodic forcing in viscous fingering of a nematic liquid crystal
We study viscous fingering of an air-nematic interface in a radial Hele-Shaw
cell when periodically switching on and off an electric field, which reorients
the nematic and thus changes its viscosity, as well as the surface tension and
its anisotropy (mainly enforced by a single groove in the cell). We observe
undulations at the sides of the fingers which correlate with the switching
frequency and with tip oscillations which give maximal velocity to smallest
curvatures. These lateral undulations appear to be decoupled from spontaneous
(noise-induced) side branching. We conclude that the lateral undulations are
generated by successive relaxations between two limiting finger widths. The
change between these two selected pattern scales is mainly due to the change in
the anisotropy. This scenario is confirmed by numerical simulations in the
channel geometry, using a phase-field model for anisotropic viscous fingering.Comment: completely rewritten version, more clear exposition of results (14
pages in Revtex + 7 eps figures
Centrosymmetric graphs and a lower bound for graph energy of fullerenes
The energy of a molecular graph G is defined as the summation of the absolute values of the eigenvalues of adjacency matrix of a graph G. In this paper, an infinite class of fullerene graphs with 10n vertices, n ≥ 2, is considered. By proving centrosymmetricity of the adjacency matrix of these fullerene graphs, a lower bound for its energy is given. Our method is general and can be extended to other class of fullerene graphs
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