arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1802.01672math.PR
收藏

稳定跳跃扩散的无穷远入口和出口

Entrance and exit at infinity for stable jump diffusions

Leif Doering, Andreas E. Kyprianou

摘要:

在20世纪50年代的开创性工作中,威廉·费勒根据进入边界(费勒爆炸检验)和从边界进入内部的能力对$-\infty\leq a<b\leq \infty$上的所有一维扩散进行了分类。费勒的技术仅限于扩散过程,因为相应的微分生成器允许显式计算和使用希勒-吉田理论。在本文中,我们研究出口和入口从无穷大的最自然的推广,即跳跃扩散的形式\[ dZ_t=σ(Z_{t-})\,dX_t, \]由稳定的Lévy过程驱动的$α\in (0,2)$。许多结果已被证明为跳跃扩散,采用各种技术发展后,费勒的工作,但出口和入口从无限边界长期以来一直是开放的。我们表明,跳跃的存在意味着功能没有看到在扩散设置漂移。对于$α\in (0,1)$,有限时间爆炸是可能的,而对于$α\in [1,2)$,从不同种类的无穷大进入是可能的。我们得到了关于$σ$的充要条件,使得(i)非爆炸解存在,(ii)相应的过渡半群在“无穷远”处延伸到一个入口点。我们的证明是基于最近的发展,通过兰珀蒂-Kiu表示和新的维纳-霍普夫因式分解的Lévy过程,躺在那里的稳定过程的路径变换。这些论点汇集了原始和复杂的应用结果使用Riesz-Bogdan-

英文摘要:

In his seminal work from the 1950s, William Feller classified all one-dimensional diffusions on $-\infty\leq a<b\leq \infty$ in terms of their ability to access the boundary (Feller's test for explosions) and to enter the interior from the boundary. Feller's technique is restricted to diffusion processes as the corresponding differential generators allow explicit computations and the use of Hille-Yosida theory. In the present article we study exit and entrance from infinity for the most natural generalization, that is, jump diffusions of the form \[ dZ_t=σ(Z_{t-})\,dX_t, \] driven by stable Lévy processes for $α\in (0,2)$. Many results have been proved for jump diffusions, employing a variety of techniques developed after Feller's work but exit and entrance from infinite boundaries has long remained open. We show that the presence of jumps implies features not seen in the diffusive setting without drift. Finite time explosion is possible for $α\in (0,1)$, whereas entrance from different kinds of infinity is possible for $α\in [1,2)$. We derive necessary and sufficient conditions on $σ$ so that (i) non-exploding solutions exist and (ii) the corresponding transition semigroup extends to an entrance point at `infinity'. Our proofs are based on very recent developments for path transformations of stable processes via the Lamperti-Kiu representation and new Wiener-Hopf factorisations for Lévy processes that lie therein. The arguments draw together original and intricate applications of results using the Riesz-Bogdan--Żak transformation, entrance laws for self-similar Markov processes, perpetual integrals of Lévy processes and fluctuation theory, which have not been used before in the SDE setting, thereby allowing us to employ classical theory such as Hunt-Nagasawa duality and Getoor's characterisation of transience and recurrence.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑