English

Loewy lengths of centers of blocks II

Representation Theory 2019-04-17 v1

Abstract

Let ZB be the center of a p-block B of a finite group with defect group D. We show that the Loewy length LL(ZB) of ZB is bounded by Dp+p1\frac{|D|}{p}+p-1 provided D is not cyclic. If D is non-abelian, we prove the stronger bound LL(ZB)<min{pd1,4pd2}LL(ZB)<\min\{p^{d-1},4p^{d-2}\} where D=pd|D|=p^d. Conversely, we classify the blocks B with LL(ZB)min{pd1,4pd2}LL(ZB)\ge\min\{p^{d-1},4p^{d-2}\}. This extends some results previously obtained by the present authors. Moreover, we characterize blocks with uniserial center.

Keywords

Cite

@article{arxiv.1703.01917,
  title  = {Loewy lengths of centers of blocks II},
  author = {Burkhard Külshammer and Yoshihiro Otokita and Benjamin Sambale},
  journal= {arXiv preprint arXiv:1703.01917},
  year   = {2019}
}

Comments

9 pages, this paper incorporates arXiv:1611.06058