Geometric characterization of intermittency in the parabolic Anderson model
Gärtner, Jürgen ; König, Wolfgang ; Molchanov, Stanislav
Ann. Probab., Tome 35 (2007) no. 1, p. 439-499 / Harvested from Project Euclid
We consider the parabolic Anderson problem ∂tu=Δu+ξ(x)u on ℝ+×ℤd with localized initial condition u(0, x)=δ0(x) and random i.i.d. potential ξ. Under the assumption that the distribution of ξ(0) has a double-exponential, or slightly heavier, tail, we prove the following geometric characterization of intermittency: with probability one, as t→∞, the overwhelming contribution to the total mass ∑xu(t, x) comes from a slowly increasing number of “islands” which are located far from each other. These “islands” are local regions of those high exceedances of the field ξ in a box of side length 2t log2t for which the (local) principal Dirichlet eigenvalue of the random operator Δ+ξ is close to the top of the spectrum in the box. We also prove that the shape of ξ in these regions is nonrandom and that u(t, ⋅) is close to the corresponding positive eigenfunction. This is the geometric picture suggested by localization theory for the Anderson Hamiltonian.
Publié le : 2007-03-14
Classification:  Parabolic Anderson problem,  intermittency,  random environment,  quenched asymptotics,  heat equation with random potential,  60H25,  82C44,  60F10,  35B40
@article{1175287751,
     author = {G\"artner, J\"urgen and K\"onig, Wolfgang and Molchanov, Stanislav},
     title = {Geometric characterization of intermittency in the parabolic Anderson model},
     journal = {Ann. Probab.},
     volume = {35},
     number = {1},
     year = {2007},
     pages = { 439-499},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1175287751}
}
Gärtner, Jürgen; König, Wolfgang; Molchanov, Stanislav. Geometric characterization of intermittency in the parabolic Anderson model. Ann. Probab., Tome 35 (2007) no. 1, pp.  439-499. http://gdmltest.u-ga.fr/item/1175287751/