Étant donnée une fonction croissante f(t), t≥0, considérons la mesure μt obtenue lorsqu'on on conditionne un mouvement brownien de sorte que Ls≤f(s), pour tout s≤t, où Ls est le temps local accumulé au temps s à l'origine. Nous montrons que les mesures μt sont tendues, et que toute limite faible de μt lorsque t→∞ est la loi d'un processus transient si t-3/2f(t) est intégrable. Nous conjecturons que cette condition est également nécessaire pour la transience et proposons un certain nombre de questions ouvertes.
We study a one-dimensional brownian motion conditioned on a self-repelling behaviour. Given a nondecreasing positive function f(t), t≥0, consider the measures μt obtained by conditioning a brownian path so that Ls≤f(s), for all s≤t, where Ls is the local time spent at the origin by time s. It is shown that the measures μt are tight, and that any weak limit of μt as t→∞ is transient provided that t-3/2f(t) is integrable. We conjecture that this condition is sharp and present a number of open problems.
Mots clés : brownian motion, conditioning, local time, entropic repulsion, integral test, transience, recurrence
@article{AIHPB_2011__47_2_539_0, author = {Benjamini, Itai and Berestycki, Nathana\"el}, title = {An integral test for the transience of a brownian path with limited local time}, journal = {Annales de l'I.H.P. Probabilit\'es et statistiques}, pages = {539--558}, publisher = {Gauthier-Villars}, volume = {47}, number = {2}, year = {2011}, doi = {10.1214/10-AIHP371}, mrnumber = {2814422}, zbl = {1216.60028}, language = {en}, url = {http://www.numdam.org/articles/10.1214/10-AIHP371/} }
TY - JOUR AU - Benjamini, Itai AU - Berestycki, Nathanaël TI - An integral test for the transience of a brownian path with limited local time JO - Annales de l'I.H.P. Probabilités et statistiques PY - 2011 SP - 539 EP - 558 VL - 47 IS - 2 PB - Gauthier-Villars UR - http://www.numdam.org/articles/10.1214/10-AIHP371/ DO - 10.1214/10-AIHP371 LA - en ID - AIHPB_2011__47_2_539_0 ER -
%0 Journal Article %A Benjamini, Itai %A Berestycki, Nathanaël %T An integral test for the transience of a brownian path with limited local time %J Annales de l'I.H.P. Probabilités et statistiques %D 2011 %P 539-558 %V 47 %N 2 %I Gauthier-Villars %U http://www.numdam.org/articles/10.1214/10-AIHP371/ %R 10.1214/10-AIHP371 %G en %F AIHPB_2011__47_2_539_0
Benjamini, Itai; Berestycki, Nathanaël. An integral test for the transience of a brownian path with limited local time. Annales de l'I.H.P. Probabilités et statistiques, Tome 47 (2011) no. 2, pp. 539-558. doi : 10.1214/10-AIHP371. http://www.numdam.org/articles/10.1214/10-AIHP371/
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