Invariance of Brownian motion associated with past and future maxima
Abstract
Let be a one-dimensional standard Brownian motion. As an application of a recent result of ours on exponential functionals of Brownian motion, we show in this paper that, for every fixed , the process given by \begin{align*} B_{s}-B_{t}-\Bigl| B_{t}+\max _{0\le u\le s}B_{u}-\max _{s\le u\le t}B_{u} \Bigr| +\Bigl| \max _{0\le u\le s}B_{u}-\max _{s\le u\le t}B_{u} \Bigr| ,\quad 0\le s\le t, \end{align*} is a Brownian motion. The path transformation that describes the above process is proven to be an involution, commute with time reversal, and preserve Pitman's transformation. A connection with Pitman's theorem is also discussed.
Keywords
Cite
@article{arxiv.2303.09163,
title = {Invariance of Brownian motion associated with past and future maxima},
author = {Yuu Hariya},
journal= {arXiv preprint arXiv:2303.09163},
year = {2025}
}
Comments
22 pages. This is the version accepted for publication in the journal of Stochastics on May 20, 2025; minor modifications have been made from the previous version