College of Liberal Arts & Sciences

# Math Physics Seminar

Speaker:

Raul Curto

Topic:

Moment Infinite Divisibility of Weighted Shifts: Sequence Conditions

**Abstract:**

We consider weighted shift operators having the property of moment infinite divisibility; that is, for any $p > 0$, the shift is subnormal when every weight (equivalently, every moment) is raised to the $p$-th power. By reconsidering sequence conditions for the weights or moments of the shift, we obtain a new characterization for such shifts, and we prove that they are, under mild conditions, robust under a variety of operations, while also rigid in certain senses. In particular, a weighted shift whose weight sequence has a limit is moment infinitely divisible if and only if its Aluthge transform is. We also consider back-step extensions, subshifts, and completions.

Event Date:

November 17, 2020 - 2:30pm to 3:20pm

Location:

Online & 309 VAN

Calendar Category:

Seminar

Seminar Category:

Mathematical Physics