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Convexity-preserving flows of totally competitive planar Lotka–Volterra equations and the geometry of the carrying simplex

Published online by Cambridge University Press:  01 November 2011

Stephen Baigent
Affiliation:
Department of Mathematics, University College London, Gower Street, London WC1E 6BT, UK ([email protected])
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Abstract

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We show that the flow generated by the totally competitive planar Lotka–Volterra equations deforms the line connecting the two axial equilibria into convex or concave curves, and that these curves remain convex or concave for all subsequent time. We apply the observation to provide an alternative proof to that given by Tineo in 2001 that the carrying simplex, the globally attracting invariant manifold that joins the axial equilibria, is either convex, concave or a straight-line segment.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 2011

References

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