Generalized (co)integrals on coideal subalgebras
Abstract
Given a a Hopf algebra , its left coideal subalgebra and a non-zero multiplicative functional on , we define the space of left -integrals . We observe that if is a Frobenius algebra and we conclude this equality for finite dimensional left coideal subalgebras of a weakly finite Hopf algebra. In general we prove that if then . Given a group-like element we define the space of -cointegrals on and linking this concept with the theory of -integrals we observe that: - every semisimple left coideal subalgebra which is preserved by the antipode squared admits a faithful -cointegral; - every unimodular finite dimensional left coideal subalgebra admitting a faithful -cointegral is preserved by the antipode square; - every non-degenerate right group-like projection in a cosemisimple Hopf algebra is a two sided group-like projection. Finally we list all -integrals for left coideals subalgebras in Taft algebras and we list all -cointegrals on them.
Keywords
Cite
@article{arxiv.1810.07114,
title = {Generalized (co)integrals on coideal subalgebras},
author = {Paweł Kasprzak},
journal= {arXiv preprint arXiv:1810.07114},
year = {2018}
}
Comments
The results are essentially the same but the presentation of them and their proofs was improved. In Section 5 the list of $\varepsilon$-integrals was completed with the case missing in the previous version