Sharpness of Some Properties of Wiener Amalgam and Modulation Spaces
نویسنده
چکیده
We prove sharp estimates for the dilation operator f(x) 7−→ f(λx), when acting on Wiener amalgam spaces W (L, L). Scaling arguments are also used to prove the sharpness of the known convolution and pointwise relations for modulation spaces M, as well as the optimality of an estimate for the Schrödinger propagator on modulation spaces.
منابع مشابه
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تاریخ انتشار 2008