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The critical exponents of parabolic equations and blow-up in Rn

Published online by Cambridge University Press:  14 November 2011

Yuan-wei Qi
Affiliation:
Department of Mathematics, Hong Kong University of Science and Technology, Hong Kong

Extract

In this paper we study the Cauchy problem in Rn of general parabolic equations which take the form ut = Δum + ts|x|σup with non-negative initial value. Here s ≧ 0, m > (n − 2)+/n, p > max (1, m) and σ > − 1 if n = 1 or σ > − 2 if n ≧ 2. We prove, among other things, that for ppc, where pcm + s(m − 1) + (2 + 2s + σ)/n > 1, every nontrivial solution blows up in finite time. But for p > pc a positive global solution exists.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1998

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