English

Equivariant Eilenberg-Watts theorem for module coalgebras

Quantum Algebra 2025-10-10 v1 Rings and Algebras

Abstract

For coalgebras CC and DD, Takeuchi proved that the category of linear functors from MC\mathfrak{M}^C to MD\mathfrak{M}^D preserving small coproducts is equivalent to the category of CC-DD-bicomodules, where MC\mathfrak{M}^C for a coalgebra CC means the category of right CC-comodules. We formulate and prove an equivariant version of this result for module coalgebras over a bialgebra. As an application, for a bialgebra HH, we establish an equivalence of the 2-category of a particular class of module categories over the monoidal category MH\mathfrak{M}^H and the 2-category of a particular class of module categories over the monoidal category HM{}_H\mathfrak{M} of left HH-modules.

Keywords

Cite

@article{arxiv.2510.07969,
  title  = {Equivariant Eilenberg-Watts theorem for module coalgebras},
  author = {Taiki Shibata and Kenichi Shimizu},
  journal= {arXiv preprint arXiv:2510.07969},
  year   = {2025}
}

Comments

22 pages

R2 v1 2026-07-01T06:26:08.310Z