On certain finite-dimensional algebras generated by two idempotents

A. Böttcher, I. M. Spitkovsky

Research output: Contribution to journalArticlepeer-review


This paper is concerned with algebras generated by two idempotents P and Q satisfying (PQ)m=(QP)m and (PQ)m-1≠(QP) m-1. The main result is the classification of all these algebras, implying that for each m≥2 there exist exactly eight nonisomorphic copies. As an application, it is shown that if an element of such an algebra has a nondegenerate leading term, then it is group invertible, and a formula for the explicit computation of the group inverse is given.

Original languageEnglish (US)
Pages (from-to)1823-1836
Number of pages14
JournalLinear Algebra and Its Applications
Issue number8
StatePublished - Oct 15 2011


  • Drazin inversion
  • Finite-dimensional algebra
  • Group inversion
  • Idempotent
  • Skew and oblique projection

ASJC Scopus subject areas

  • Algebra and Number Theory
  • Numerical Analysis
  • Geometry and Topology
  • Discrete Mathematics and Combinatorics


Dive into the research topics of 'On certain finite-dimensional algebras generated by two idempotents'. Together they form a unique fingerprint.

Cite this