{ "id": "2010.01533", "version": "v1", "published": "2020-10-04T10:29:58.000Z", "updated": "2020-10-04T10:29:58.000Z", "title": "A maximal $L_p$-regularity theory to initial value problems with time measurable nonlocal operators generated by additive processes", "authors": [ "Jae-Hwan Choi", "Ildoo Kim" ], "comment": "44 pages", "categories": [ "math.PR", "math.AP" ], "abstract": "Let $Z=(Z_t)_{t\\geq0}$ be an additive process with a bounded triplet $(0,0,\\Lambda_t)_{t\\geq0}$. Then the infinitesimal generators of $Z$ is given by time dependent nonlocal operators as follows: \\begin{align*} \\mathcal{A}_Z(t)u(t,x) &=\\lim_{h\\downarrow0}\\frac{\\mathbb{E}[u(t,x+Z_{t+h}-Z_t)-u(t,x)]}{h}=\\int_{\\mathbb{R}^d}(u(t,x+y)-u(t,x)-y\\cdot \\nabla u(t,x)1_{|y|\\leq1})\\Lambda_t(dy). \\end{align*} Suppose that L\\'evy measures $\\Lambda_t$ have a lower bound (Assumption 2.10) and satisfy a weak-scaling property (Assumption 2.11). We emphasize that there is no regularity condition on L\\'evy measures $\\Lambda_t$ and they do not have to be symmetric. In this paper, we establish the $L_p$-solvability to initial value problem (IVP) \\begin{equation} \\label{20.07.15.17.02} \\frac{\\partial u}{\\partial t}(t,x)=\\mathcal{A}_Z(t)u(t,x),\\quad u(0,\\cdot)=u_0,\\quad (t,x)\\in(0,T)\\times\\mathbb{R}^d, \\end{equation} where $u_0$ is contained in a scaled Besov space $B_{p,q}^{s;\\gamma-\\frac{2}{q}}(\\mathbb{R}^d)$ (see Definition 2.8) with a scaling function $s$, exponent $p \\in (1,\\infty)$, $q\\in[1,\\infty)$, and order $\\gamma \\in [0,\\infty)$. We show that IVP is uniquely solvable and the solution $u$ obtains full-regularity gain from the diffusion generated by a stochastic process $Z$. In other words, there exists a unique solution $u$ to IVP in $L_q((0,T);H_p^{\\mu;\\gamma}(\\mathbb{R}^d))$, where $H_p^{\\mu;\\gamma}(\\mathbb{R}^d)$ is a generalized Bessel potential space (see Definition 2.3). Moreover, the solution $u$ satisfies $$ \\|u\\|_{L_q((0,T);H_p^{\\mu;\\gamma}(\\mathbb{R}^d))}\\leq N(1+T^2)\\|u_0\\|_{B_{p,q}^{s;\\gamma-\\frac{2}{q}}(\\mathbb{R}^d)}, $$ where $N$ is independent of $u$, $u_0$, and $T$.", "revisions": [ { "version": "v1", "updated": "2020-10-04T10:29:58.000Z" } ], "analyses": { "subjects": [ "35S10", "60H30", "47G20", "42B25" ], "keywords": [ "time measurable nonlocal operators", "initial value problem", "additive process", "regularity theory", "levy measures" ], "note": { "typesetting": "TeX", "pages": 44, "language": "en", "license": "arXiv", "status": "editable" } } }