Absolutely continuous spectrum for CMV matrices with small quasi-periodic Verblunsky coefficients

Li, LongDamanik, DavidZhou, Qi2022-09-292022-09-292022Li, Long, Damanik, David and Zhou, Qi. "Absolutely continuous spectrum for CMV matrices with small quasi-periodic Verblunsky coefficients." <i>Transactions of the American Mathematical Society,</i> 375, no. 9 (2022) American Mathematical Society: 6093-6125. https://doi.org/10.1090/tran/8696.https://hdl.handle.net/1911/113426We consider standard and extended CMV matrices with small quasi-periodic Verblunsky coefficients and show that on their essential spectrum, all spectral measures are purely absolutely continuous. This answers a question of Barry Simon from 2005.engThis pre-print is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licenseAbsolutely continuous spectrum for CMV matrices with small quasi-periodic Verblunsky coefficientsJournal article2102-00586https://doi.org/10.1090/tran/8696