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Boundedness of Lusin-area and functions on localized BMO spaces over doubling metric measure spaces

✍ Scribed by Haibo Lin; Eiichi Nakai; Dachun Yang


Publisher
Elsevier Science
Year
2011
Tongue
French
Weight
258 KB
Volume
135
Category
Article
ISSN
0007-4497

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✦ Synopsis


Let X be a doubling metric measure space. If X has the δ-annular decay property for some δ ∈ (0, 1], the authors then establish the boundedness of the Lusin-area function, which is defined via kernels modeled on the semigroup generated by the Schrödinger operator, from localized spaces BMO ρ (X ) to BLO ρ (X ) without invoking any regularity of considered kernels. The same is true for the g * λ function and unlike the Lusin-area function, in this case, X is not necessary to have the δ-annular decay property. Moreover, for any metric space, the authors introduce the weak geodesic property and the monotone geodesic property, which are proved to be respectively equivalent to the chain ball property of Buckley. Recall that Buckley proved that any length space has the chain ball property and, for any metric space equipped with a doubling measure, the chain ball property implies the δ-annular decay property for some δ ∈ (0, 1]. Moreover, using some results on pointwise multipliers of bmo(R), the authors construct a counterexample to show that there exists a non-negative function which is in bmo(R), but not in blo(R); this further indicates that the above