5,405 research outputs found
On Capital Dependent Dynamics of Knowledge
We investigate the dynamics of growth models in terms of dynamical system
theory. We analyse some forms of knowledge and its influence on economic
growth. We assume that the rate of change of knowledge depends on both the rate
of change of physical and human capital. First, we study model with constant
savings. The model with optimised behaviour of households is also considered.
We show that the model where the rate of change of knowledge depends only on
the rate of change of physical capital can be reduced to the form of the
two-dimensional autonomous dynamical system. All possible evolutional paths and
the stability of solutions in the phase space are discussed in details. We
obtain that the rate of growth of capital, consumption and output are greater
in the case of capital dependent rate of change of knowledge.Comment: 11 pages, 5 figures; presented at 2nd Polish Symposium on Econo- and
Sociophysics, Krakow, Poland, 21-22 April 2006; to be published in Acta Phys.
Pol.
Phantom cosmology as a simple model with dynamical complexity
We study the Friedmann-Robertson-Walker model with phantom fields modelled in
terms of scalar fields. We apply the Ziglin theory of integrability and find
that the flat model is nonintegrable. Then we cannot expect to determine simple
analytical solutions of the Einstein equations. We demonstrate that there is
only a discrete set of parameters where this model is integrable. For
comparison we describe the phantoms fields in terms of the barotropic equation
of state. It is shown that in the contrast to the phantoms modelled as scalar
fields, the dynamics is always integrable and phase portraits are constructed.
In this case we find the duality relation.Comment: RevTeX4, 11 pages, 2 figures; rewritten (v.2); new section on complex
dynamics in cases with and without spontaneous symmetry breaking (v.3); this
new section on numerical analysis of complex dynamics was dropped, upload to
match version in PRE (v.4
Mini-documentaries
Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1979.Includes index.The considerations, potential and limit ations of very short films as exemplified by the production of thirty- eight Mini-Documentaries for the Aspen Movie Map Project. The films are included on videotape.by Marek Zalewski.M.S.V.S
Deconstructing 5D supersymmetric U(1) gauge theories on orbifolds
We investigate deconstruction of five dimensional supersymmetric abelian
gauge theories compactified on , with various sets of bulk and matter
multiplets. The problem of anomalies, chirality and stability in the
deconstructed theories is discussed. We find that for most of the 5d brane/bulk
matter assignments there exists the deconstructed version. There are, however,
some exceptions.Comment: Discussion of mixed anomalies and some clarifying commments added.
Version to appear in Phys.Lett.
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