On the boundedness of the mapping $f\to |f|$ in Besov spaces
Oswald, Patrick
Commentationes Mathematicae Universitatis Carolinae, Tome 33 (1992), p. 57-66 / Harvested from Czech Digital Mathematics Library
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For $1\leq p\leq\infty$, precise conditions on the parameters are given under which the particular superposition operator $T:f\to |f|$ is a bounded map in the Besov space $B^s_{p,q}(R^1)$. The proofs rely on linear spline approximation theory.

Publié le : 1992-01-01
Classification:  35B45,  41A15,  46E35,  47H30 
@article{118471,
     author = {Patrick Oswald},
     title = {On the boundedness of the mapping $f\to |f|$ in Besov spaces},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {33},
     year = {1992},
     pages = {57-66},
     zbl = {0766.46018},
     mrnumber = {1173747},
     language = {en},
     url = {http://dml.mathdoc.fr/item/118471}
}

Oswald, Patrick. On the boundedness of the mapping $f\to |f|$ in Besov spaces. Commentationes Mathematicae Universitatis Carolinae, Tome 33 (1992) pp. 57-66. http://gdmltest.u-ga.fr/item/118471/

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