Discontinuity of the Lempert function of the spectral ball
arXiv:0811.3093
Abstract
We give some further criteria for continuity or discontinuity of the Lempert funtion of the spectral ball , with respect to one or both of its arguments, in terms of cyclicity the matrices involved.
12 pages; the converse to theorem 1.3, mistakenly claimed in v1 & 2, excised from v3, is now proved in some cases