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• January 26, 2007, Friday - 15h00 (Room P 3.10):

Meromorphic factorization revisited and application to a group of matrices

  Teresa Malheiro

(Universidade do Minho, Guimarães)

Abstract. It is shown that the 2x2 symbols in a class of exponentials of nilpotent matrices can be reduced, by splitting some rational factors, to a very simple normal form. A meromorphic factorization [1] of these symbols is thus naturally defined and by approaching the problem of transforming it into a generalized factorization from a point of view different from that of [1], we study the invertibility and the Fredholm properties of the Toeplitz operators with symbols in that class. These results simplify and generalize those obtained in [2]. This is a joint work with Cristina Câmara, IST, Lisboa.
[1] Câmara, M. C., Lebre, A., Speck, F.-O.: Generalised factorisation for a class of Jones form matrix functions, Proc. Roy. Soc. Ed., 123A (1993) 401-422.
[2] Câmara, M.C., Malheiro, M.T.: Wiener-Hopf factorization for a group of exponentials of nilpotent matrices, Linear Algebra Appl. 320(1-3) (2000) 79-96.

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