Abstract:
Let
H
be an infinite dimensional complex separable Hilbert space and
B(H)
be the algebra of all bounded linear operators on
H
.
T \in B(H)
is said to satisfy property
(R_1)
if
\sigma _a(T)\backslash \sigma _ab(T) \subseteq \pi _00(T)
, where
\sigma _a(T)
and
\sigma _ab(T)
denote the approximate point spectrum and the Browder essential approximate point spectrum of
T
respectively, and
\pi _00(T) = \ \lambda \in \rmiso\sigma (T):0 < \rmdimN(T - \lambda I) < \infty \ 
. If
\sigma _a(T)\backslash \sigma _ab(T) = \pi _00(T)
,
T
is said to satisfy property
(R)
. In this paper, by using the new spectrum, the necessary and sufficient conditions for which the property
(R_1)
or property
(R)
holds for bounded linear operators and its functions are given. Also, the new judgements for a-Weyl's theorem and property
(R)
are obtained.