2009/01/16 by Victor Katsnelson, Katsnelson, Victor, Ronny Machluf +1
Mathematics · #47A10 #47A38 #47B06 #47B35 #Classical Analysis and ODEs (math.CA) #FOS: Mathematics #Spectral Theory (math.SP) #math.CA #math.SP #msc:47A10 #msc:47A38 #msc:47B06 #msc:47B35
paper · pdf · doi:10.48550/arxiv.0901.2555
20 pages
arxiv created 2009/01/16 · arxiv updated 2009/12/01
Let (\mathscrF) be the one dimensional Fourier-Plancherel operator and (E) be a subset of the real axis. The truncated Fourier operator is the operator (\mathscrFE) of the form (\mathscrFE=PE\mathscrFPE), where ((PEx)(t)=χE(t)x(t)), and (χE(t)) is the indicator function of the set (E). In the presented first part of the work, the basic properties of the operator (\mathscrFE) according to the set (E) are discussed. Among these properties there are the following one. The operator (\mathscrFE): 1. has a not-trivial null-space; 2. is strictly contractive; 3. is a normal operator; 4. is a Hilbert-Schmidt operator; 5. is a trace class operator.