Abstract
Differential inequality methods are developed for establishing upper and lower bounds on the total particle numberN(t)=∫θ(x,t) d3 x associated with solutions to nonlinear reaction-diffusion equations of the form ∂θ/∂t=D∇2θ+fθ-gθn+1, whereD(>0),n(>0),f andg are constant parameters. If finite in a neighborhood oft=0,N(t) is bounded below for allt≥0 by a certain derived function oft for equations withg≥0. An upper bound onN(t) is obtained for equations withn=1,f<0 andg<0. These results provide general preservation and extinction criteria for the total particle number.
Similar content being viewed by others
Literature
Cherkas, B. M. 1972. “On Nonlinear Diffusion Equations.”J. Diff. Equations,11, 284–291.
Fisher, R. A. 1937. “The Wave of Advance of Advantageous Genes.”Ann. Eugen.,7, 355–369.
Montroll, E. W. 1968. “Lectures on Nonlinear Rate Equations, Especially Those with Quadratic Nonlinearities.” InLectures in Theoretical Physics, Barut, A. O. and W. E. Britton, eds. New York: Gordon & Breach, pp. 531–573.
Rosen, G. 1971. “Minimum Value forc in the Sobolev Inequality.”SIAM J. Appl. Math.,21, 30–32.
— 1974. “Approximate Solution to the Generic Initial Value Problem for Nonlinear Reaction-Diffusion Equations.”26, 221–226.
Schwarz, H. A. 1969. “Applications of the Spur Diffusion Model to the Radiation Chemistry of Aqueous Solutions.”J. Phys. Chem.,73, 1928–1936.
Taam, C. T. 1965. “On Nonlinear Diffusion Equations.”J. Diff. Equations,3, 485–491.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Rosen, G. Bounds on the total particle number for species governed by reaction-diffusion equations in the infinite spatial domain. Bltn Mathcal Biology 36, 589–593 (1974). https://doi.org/10.1007/BF02463270
Issue Date:
DOI: https://doi.org/10.1007/BF02463270