A note on truncations in fractional Sobolev spaces

Roberta Musina, Alexander I. Nazarov
2019 Bulletin of Mathematical Sciences  
We study the Nemytskii operators u → |u| and u → u ± in fractional Sobolev spaces H s (R n ), s > 1.
doi:10.1142/s1664360719500012 fatcat:5rfxcuolxnb7bflliartrbw4za