A compact set without Markov’s property but with an extension operator for C∞-functions
Goncharov, Alexander
Studia Mathematica, Tome 119 (1996), p. 27-35 / Harvested from The Polish Digital Mathematics Library
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We give an example of a compact set K ⊂ [0, 1] such that the space ℇ(K) of Whitney functions is isomorphic to the space s of rapidly decreasing sequences, and hence there exists a linear continuous extension operator L:ℇ(K)→C∞[0,1]. At the same time, Markov’s inequality is not satisfied for certain polynomials on K.

Publié le : 1996-01-01
EUDML-ID : urn:eudml:doc:216284 
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     title = {A compact set without Markov's property but with an extension operator for $C^$\infty$$-functions},
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     year = {1996},
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Goncharov, Alexander. A compact set without Markov’s property but with an extension operator for $C^∞$-functions. Studia Mathematica, Tome 119 (1996) pp. 27-35. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv119i1p27bwm/

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