On Doob’s inequality and Burkholder’s inequality in weak spaces

Collectanea Mathematica - Tập 67 - Trang 461-483 - 2015
Masato Kikuchi1
1Department of Mathematics, University of Toyama, Toyama, Japan

Tóm tắt

Let X be a Banach function space over a nonatomic probability space. We associate with X the weak space $${\mathrm {w}}\text {-}{X}$$ , which is a quasi-Banach space defined in a natural way. We give necessary and sufficient conditions for Doob’s inequality in $${\mathrm {w}}\text {-}{X}$$ to be valid, and necessary and sufficient conditions for Burkholder’s inequality in $${\mathrm {w}}\text {-}{X}$$ to be valid.

Tài liệu tham khảo

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