Metric Entropy of Integration Operators and Small Ball Probabilities for the Brownian Sheet
نویسندگان
چکیده
Let Td : L2([0, 1] ) C([0, 1] ) be the d-dimensional integration operator. We show that its Kolmogorov and entropy numbers decrease with order at least k(log k)d&1 . From this we derive that the small ball probabilities of the Brownian sheet on [0, 1] under the C([0, 1] )-norm can be estimated from below by exp(&C= |log =|), which improves the best known lower bounds considerably. We also get similar results with respect to certain Orlicz norms. 1999 Academic Press
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