Dans cet article, on presente une étude d'une version du modèle de Hastings-Levitov HL (0) où la croissance est anisotrope. Deux limites d'échelle naturelles sont établies, et nous décrivons précisément les effets de l'anisotropie. Nous montrons que les formes limites du modèle peuvent être réalisées comme remplissages associés à l'équation de Loewner et que l'évolution de la mesure harmonique sur la frontière des agrégats tend vers un certain flot deterministe. Nous caractérisons enfin les fluctuations stochastiques autour de ce flot.
We consider a variation of the standard Hastings-Levitov model HL(0), in which growth is anisotropic. Two natural scaling limits are established and we give precise descriptions of the effects of the anisotropy. We show that the limit shapes can be realised as Loewner hulls and that the evolution of harmonic measure on the cluster boundary can be described by the solution to a deterministic ordinary differential equation related to the Loewner equation. We also characterise the stochastic fluctuations around the deterministic limit flow.
@article{AIHPB_2012__48_1_235_0, author = {Johansson Viklund, Fredrik and Sola, Alan and Turner, Amanda}, title = {Scaling limits of anisotropic Hastings-Levitov clusters}, journal = {Annales de l'I.H.P. Probabilit\'es et statistiques}, volume = {48}, year = {2012}, pages = {235-257}, doi = {10.1214/10-AIHP395}, mrnumber = {2919205}, zbl = {1251.82025}, language = {en}, url = {http://dml.mathdoc.fr/item/AIHPB_2012__48_1_235_0} }
Johansson Viklund, Fredrik; Sola, Alan; Turner, Amanda. Scaling limits of anisotropic Hastings-Levitov clusters. Annales de l'I.H.P. Probabilités et statistiques, Tome 48 (2012) pp. 235-257. doi : 10.1214/10-AIHP395. http://gdmltest.u-ga.fr/item/AIHPB_2012__48_1_235_0/
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