332 research outputs found
Need, Greed and Noise: Competing Strategies in a Trading Model
We study an economic model where agents trade a variety of products by using
one of three competing rules: "need", "greed" and "noise". We find that the
optimal strategy for any agent depends on both product composition in the
overall market and composition of strategies in the market. In particular, a
strategy that does best on pairwise competition may easily do much worse when
all are present, leading, in some cases, to a "paper, stone, scissors" circular
hierarchy.Comment: 10 pages, 6 figure
Physics of Fashion Fluctuations
We consider a market where many agents trade many different types of products
with each other. We model development of collective modes in this market, and
quantify these by fluctuations that scale with time with a Hurst exponent of
about 0.7. We demonstrate that individual products in the model occationally
become globally accepted means of exchange, and simultaneously become very
actively traded. Thus collective features similar to money spontaneously
emerge, without any a priori reason.Comment: 9 pages RevTeX, 5 Postscript figure
Transverse Isotropy in Identical Particle Scattering
It is pointed out that the cross section for the scattering of identical
charged bosons is isotropic over a broad angular range around 90 degrees when
the Sommerfeld parameter has a critical value, which depends exclusively on the
spin of the particle. A discussion of systems where this phenomenon can be
observed is presented.Comment: 8 pages, RevTeX format, 2 figures (.eps format
A Semiclassical Approach to Fusion Reactions
The semiclassical method of Alder and Winther is generalized to study fusion
reactions. As an illustration, we evaluate the fusion cross section in a
schematic two-channel calculation. The results are shown to be in good
agreement with those obtained with a quantal Coupled-Channels calculation. We
suggest that in the case of coupling to continuum states this approach may
provide a simpler alternative to the Continuum Discretized Coupled-Channels
method.Comment: 6 pages, 1 figure, invited talk at the International Symposium "A new
era of Nuclear Structure Physics", Niigata, Japan, Nov. 19-22 200
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