## Topological Methods in Nonlinear Analysis

### Combining fast, linear and slow diffusion

#### Abstract

Although the pioneering studies of G. I. Barenblatt [On some unsteady motions of a liquid or a gas in a porous medium, Prikl. Mat. Mekh. 16 (1952), 67–68] and A. G. Aronson and L. A. Peletier [Large time behaviour of solutions of some porous medium equation in bounded domains, J. Differential Equations 39 (1981), 378–412] did result into a huge industry around the porous media equation, none further study analyzed the effect of combining fast, slow, and linear diffusion simultaneously, in a spatially heterogeneous porous medium. Actually, it might be this is the first work where such a problem has been addressed. Our main findings show how the heterogeneous model possesses two different regimes in the presence of a priori bounds. The minimal steady-state of the model exhibits a genuine fast diffusion behavior, whereas the remaining states are rather reminiscent of the purely slow diffusion model. The mathematical treatment of these heterogeneous problems should deserve a huge interest from the point of view of its applications in fluid dynamics and population evolution.

#### Article information

Source
Topol. Methods Nonlinear Anal., Volume 23, Number 2 (2004), 275-300.

Dates
First available in Project Euclid: 31 May 2016

https://projecteuclid.org/euclid.tmna/1464731410

Mathematical Reviews number (MathSciNet)
MR2078193

Zentralblatt MATH identifier
1129.35310

#### Citation

López-Gómez, Julián; Suárez, Antonio. Combining fast, linear and slow diffusion. Topol. Methods Nonlinear Anal. 23 (2004), no. 2, 275--300. https://projecteuclid.org/euclid.tmna/1464731410

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