| 실적년도 | 2010 년 |
|---|---|
| 논문구분 | 국외 |
| 총저자 | Woo Young Lee |
| 학술지명 | Journal of Mathematical Analysis and Applications |
| 권(Vol.) | 371 |
| 호(No.) | 1 |
| 게재년월 | 년 월 |
| Impact Factor | |
| SCI 등재 | SCI |
| 비고 |
In this paper it is shown that if an operator $T$ satisfies
$||p(T)||le ||p||_{sigma(T)}$ for every polynomial $p$ and the
polynomially convex hull of $sigma(T)$ is a Carath'{e}odory region
whose accessible boundary points lie in rectifiable Jordan arcs on
its boundary, then $T$ has a nontrivial invariant subspace. As a
corollary, it is also shown that if $T$ is a hyponormal operator and
the outer boundary of $sigma(T)$ has at most finitely many prime
ends corresponding to singular points on $partialmathbb D$ and has
a tangent at almost every point on each Jordan arc, then $T$ has a
nontrivial invariant subspace.
