Continuous Fourier Transform of Vanishing Fast Functions: Explained

Delta2
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Can someone tell me if the continuous Fourier transform of a continuous (and vanishing fast enough ) function is also a continuous function?
 
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I can tell you more: in fact, if f \in L^{1}(\mathbb R) then its Fourier Transform is uniformly continuous.
 
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Thanks very much but can u ... remind me which functions belong to L1(R)?
 
Delta² said:
Thanks very much but can u ... remind me which functions belong to L1(R)?

It are all the functions ##f:\mathbb{R}\rightarrow \mathbb{R}## which are absolutely integrable. That is, for which

\int_{-\infty}^{+\infty} |f(x)|dx

is finite (and the integral makes sense).
 
A sphere as topological manifold can be defined by gluing together the boundary of two disk. Basically one starts assigning each disk the subspace topology from ##\mathbb R^2## and then taking the quotient topology obtained by gluing their boundaries. Starting from the above definition of 2-sphere as topological manifold, shows that it is homeomorphic to the "embedded" sphere understood as subset of ##\mathbb R^3## in the subspace topology.
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