A Weak-Type Inequality for Orthogonal Submartingales and Subharmonic Functions

• Autorzy: Osękowski A.

Identyfikatory

DOI

10.4064/ba59-3-7

• Języki publikacji: EN

Abstrakty

EN

Let X be a submartingale starting from 0, and Y be a semimartingale which is orthogonal and strongly differentially subordinate to X. The paper contains the proof of the sharp estimate P(supt≥0|Yt|≥1)≤3.375…∥X∥1. As an application, a related weak-type inequality for smooth functions on Euclidean domains is established.

Słowa kluczowe

EN

submartingale; subharmonic function; strong differential subordination; weak type inequality; best constants

• Wydawca: Instytut Matematyczny PAN
• Czasopismo: Bulletin of the Polish Academy of Sciences. Mathematics
• Rocznik: 2011
• Tom: Vol. 59, no 3
• Strony: 261--274
• Opis fizyczny: Bibliogr. 12 poz.

Twórcy

autor

Osękowski A.

• Faculty of Mathematics, Informatics and Mechanics University of Warsaw Banacha 2 02-097 Warszawa, Poland

Bibliografia

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