English

Ideals in $L(L_1)$

Functional Analysis 2019-11-14 v2

Abstract

The main result is that there are infinitely many; in fact, a continuum; of closed ideals in the Banach algebra L(L1)L(L_1) of bounded linear operators on L1(0,1)L_1(0,1). This answers a question from A. Pietsch's 1978 book "Operator Ideals". The proof also shows that L(C[0,1])L(C[0,1]) contains a continuum of closed ideals. Finally, a duality argument yields that L()L(\ell_\infty) has a continuum of closed ideals.

Keywords

Cite

@article{arxiv.1811.06571,
  title  = {Ideals in $L(L_1)$},
  author = {William B. Johnson and Gilles Pisier and Gideon Schechtman},
  journal= {arXiv preprint arXiv:1811.06571},
  year   = {2019}
}

Comments

Final version, will appear in Mathematische Annalen

R2 v1 2026-06-23T05:17:32.286Z