Convexity of the Krein space tracial numerical range and Morse theory

• Author(s): Nakazato, Hiroshi ; Bebiano, Natália ; Providência, João da
• Date: 2009
• Persistent ID: http://hdl.handle.net/10316/13648
• Origin: Estudo Geral - Universidade de Coimbra
• Subject(s): Numerical range; Indefinite inner product; J-Hermitian matrix; Non-interlacing
• Document Type: Preprint
• Language: English

Description

In this paper we present a Krein space convexity theorem on the tracial-numerical range of a matrix. This theorem is the analogue of Westwick's theorem. The proof is an application of Morse theory.