The iterated Aluthge transforms of a matrix converge
نویسندگان
چکیده
Given an r × r complex matrix T , if T = U |T | is the polar decomposition of T , then, the Aluthge transform is defined by ∆ (T ) = |T |U |T |. Let ∆n(T ) denote the n-times iterated Aluthge transform of T , i.e. ∆0(T ) = T and ∆n(T ) = ∆(∆n−1(T )), n ∈ N. We prove that the sequence {∆n(T )}n∈N converges for every r × r matrix T . This result was conjecturated by Jung, Ko and Pearcy in 2003. We also analyze the regularity of the limit function.
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