Martingale Hardy spaces with variable exponents

Abstract

In this paper, we introduce Hardy spaces with variable exponents defined on a probability space and develop the martingale theory of variable Hardy spaces. We prove the weak type and strong type inequalities on Doob's maximal operator and get a $(1,p(\cdot),\infty)$-atomic decomposition for Hardy martingale spaces associated with conditional square functions. As applications, we obtain a dual theorem and the John-Nirenberg inequalities in the frame of variable exponents. The key ingredient is that we find a condition with probabilistic characterization of $p(\cdot)$ to replace the so-called log-H\"{o}lder continuity condition in $\mathbb {R}^n.$Comment: Banach Journal of Mathematical Analysis, to appea

Atomic decompositions of martingale Hardy-Lorentz spaces and interpolation

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Mixed Martingale Hardy Spaces

“…Moreover, Musielak-Orlicz-Hardy spaces were studied in Yang et al [44]. These results were also investigated for martingale Hardy spaces in Jiao et al [26,27] and Xie et al [42]. The mixed-norm classical Hardy spaces were intensively studied by Huang et al [22,23] and Huang and Yang [24].…”

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