Effect of Random Time Changes on Loewner Hulls

Kei Kobayashi; Joan Lind; Andrew Starnes

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arXiv · 1802.09466

Effect of Random Time Changes on Loewner Hulls

Kei Kobayashi·Joan Lind·Andrew Starnes

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Abstract

Loewner hulls are determined by their real-valued driving functions. We study the geometric effect on the Loewner hulls when the driving function is composed with a random time change, such as the inverse of an $α$-stable subordinator. In contrast to SLE, we show that for a large class of random time changes, the time-changed Brownian motion process does not generate a simple curve. Further we develop criteria which can be applied in many situations to determine whether the Loewner hull generated by a time-changed driving function is simple or non-simple. To aid our analysis of an example with a time-changed deterministic driving function, we prove a deterministic result that a driving function that moves faster than $at^r$ for $r \in (0,1/2)$ generates a hull that leaves the real line tangentially.

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BibTeX RIS

Kei Kobayashi, Joan Lind, Andrew Starnes. 2019-10-13. Effect of Random Time Changes on Loewner Hulls. https://arxiv.org/abs/1802.09466

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