论文标题
限制不变子空间的频谱
The spectrum of the restriction to an invariant subspace
论文作者
论文摘要
令$ x $为Banach Space，B（X）$中的$ A \ $ A \ $ M $是$ a $的不变子空间。我们提供了另一种证据，即，如果$ a $ a $ to $ m $的限制的频谱包含$ a $频谱中任何给定孔中的点，则整个孔在限制的范围内。
Let $X$ be a Banach space, $A\in B(X)$ and $M$ be an invariant subspace of $A$. We present an alternative proof that, if the spectrum of the restriction of $A$ to $M$ contains a point that is in any given hole in the spectrum of $A$, then the entire hole is in the spectrum of the restriction.
