Fourier transform, null variety, and Laplacian's eigenvalues
نویسندگان
چکیده
منابع مشابه
Fourier transform , null variety , and Laplacian ’ s eigenvalues ∗
We consider a quantity κ(Ω) — the distance to the origin from the null variety of the Fourier transform of the characteristic function of Ω. We conjecture, firstly, that κ(Ω) is maximized, among all convex balanced domains Ω ⊂ R of a fixed volume, by a ball, and also that κ(Ω) is bounded above by the square root of the second Dirichlet eigenvalue of Ω. We prove some weaker versions of these con...
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 2009
ISSN: 0022-1236
DOI: 10.1016/j.jfa.2009.06.022