Gaussian estimates and instantaneous blowup
For L a second order linear elliptic differential operator on ℝN, one is usually interested in finding positive solutions of the heat equation u\t = Lu+Vu, where V is a nonnegative potential. But for L the Laplacian, it was discovered by [BG] in 1984 that positive solutions may not exist if V is too singular. We use Gaussian estimates to extend this result to the case when L is not symmetric. © 2007 Birkhäuser Verlag Basel/Switzerland.
Goldstein, J., & Kombe, I. (2008). Gaussian estimates and instantaneous blowup. Positivity, 12 (1), 75-82. https://doi.org/10.1007/s11117-007-2105-7