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# Wydawnictwa / Czasopisma IMPAN / Studia Mathematica / Wszystkie zeszyty

## Spectral theory of SG pseudo-differential operators on $L^p(\mathbb R^n)$

### Tom 187 / 2008

Studia Mathematica 187 (2008), 185-197 MSC: Primary 35S05, 47G30; Secondary 47A53. DOI: 10.4064/sm187-2-5

#### Streszczenie

To every elliptic SG pseudo-differential operator with positive orders, we associate the minimal and maximal operators on $L^p(\mathbb R^n),\,1< p< \infty,$ and prove that they are equal. The domain of the minimal (= maximal) operator is explicitly computed in terms of a Sobolev space. We prove that an elliptic SG pseudo-differential operator is Fredholm. The essential spectra of elliptic SG pseudo-differential operators with positive orders and bounded SG pseudo-differential operators with orders $0,0$ are computed.

#### Autorzy

• Aparajita DasguptaDepartment of Mathematics and Statistics
York University
4700 Keele Street
e-mail
• M. W. WongDepartment of Mathematics and Statistics
York University
4700 Keele Street