Let a family of linear operators
{An}(n = 1,2,⋯) in a Banach space X have the resolvents {R(λ;An)} which is
equicontinuous in n. Suppose that {An} is a Cauchy sequence on a dense set. Then
the question of convergence arises; when will {R(λ;An)x} be a Cauchy sequence for
all x ∈ X?
This problem is treated in some special cases and an application to the following
theorem is presented.
Let A be the generator of a positive contraction semigroup ∑
and let B be a
linear operator with domain 𝒟(B) ⊃𝒟(A) in a weakly complete Banach lattice
X.
Then A + B or its closed extension generates a positive contraction
semi-group Σ′ which dominates Σ if and only if A + B is dissipative and B is
positive.
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