Fefferman, Charles
April 2009
Bulletin (New Series) of the American Mathematical Society;Apr2009, Vol. 46 Issue 2, p207
Academic Journal
Given a function f : E → R with E ⊂ ℝ:n, we explain how to decide whether f extends to a ⊂m function F on ℝn. If E is finite, then one can efficiently compute an F as above, whose Cm norm has the least possible order of magnitude (joint work with B. Klartag).


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