Acta mathematica scientia,Series A ›› 2013, Vol. 33 ›› Issue (5): 966-976.

• Articles • Previous Articles     Next Articles

Critical Exponents of the Cauchy Problem for Nonlinear Diffusive Equations

 LI Zhong-Ping, DU Wan-Juan, MU Chun-Lai   

  1. College of Mathematic and Information, China West Normal University, Sichuan Nanchong 637002; College of Mathematics and Statistics, Chongqing University, Chongqing 400044
  • Received:2012-03-08 Revised:2013-06-23 Online:2013-10-25 Published:2013-10-25
  • Supported by:

    国家自然科学基金面上项目(11071266)、国家自然科学基金数学天元项目(11226181)和西华师范大学科研项目(12B024, 12A032)资助.

Abstract:

In this paper, we investigate the large time behavior of solution to nonlinear diffusive equations ut=div(|nabla u|p-2 nabla u)+|x|σuq with nontrivial, nonnegative initial data. Here p>2, σ>0 and q>p-1. We prove that qc=p-1+p+σ /N is the critical Fujita exponent. That is, if q<qc then every positive solution blows up in finite time, but for q>qc, there exist both global and non-global solutions to the problem. Furthermore, we establish the secondary critical exponent on the decay asymptotic behavior of an initial value at infinity.

Key words: Critical Fujita exponent, Secondary critical exponent, Nonlinear diffusive equations

CLC Number: 

  • 35K50
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