منابع مشابه
Composition in Fractional Sobolev Spaces
1. Introduction. A classical result about composition in Sobolev spaces asserts that if u ∈ W k,p (Ω)∩L ∞ (Ω) and Φ ∈ C k (R), then Φ • u ∈ W k,p (Ω). Here Ω denotes a smooth bounded domain in R N , k ≥ 1 is an integer and 1 ≤ p < ∞. This result was first proved in [13] with the help of the Gagliardo-Nirenberg inequality [14]. In particular if u ∈ W k,p (Ω) with kp > N and Φ ∈ C k (R) then Φ • ...
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ژورنال
عنوان ژورنال: Bulletin of the American Mathematical Society
سال: 1972
ISSN: 0002-9904
DOI: 10.1090/s0002-9904-1972-12840-4