### The thin viscous flow equation in higher space dimensions

#### Abstract

We prove local integral (entropy) estimates for nonnegative solutions of the fourth-order degenerate parabolic equation $$u_t+ \div (u^n\nabla\Delta u)=0$$ in space dimensions two and three. These estimates enable us to show that solutions have finite speed of propagation if $n\in(\frac 18,2)$ and that the support cannot shrink if the growth exponent $n$ is larger than $3/2$. In addition, we prove decay estimates for solutions of the Cauchy problem and a growth estimate for their support.

#### Article information

Source
Adv. Differential Equations, Volume 3, Number 3 (1998), 417-440.

Dates
First available in Project Euclid: 19 April 2013

Mathematical Reviews number (MathSciNet)
MR1751951

Zentralblatt MATH identifier
0954.35035

Subjects
Primary: 35K55: Nonlinear parabolic equations
Secondary: 35K65: Degenerate parabolic equations 76D08: Lubrication theory

#### Citation

Bertsch, Michiel; Dal Passo, Roberta; Garcke, Harald; Grün, Günther. The thin viscous flow equation in higher space dimensions. Adv. Differential Equations 3 (1998), no. 3, 417--440. https://projecteuclid.org/euclid.ade/1366399848