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arXiv · 1512.04296

Expression asymptotique des valeurs propres d'une matrice de Toeplitz \`a symbole r\'eel

Philippe Rambour
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Abstract

This work provides two results obtained as a consequence of an inversion formula for Toeplitz matrices with real symbol. First we obtain an asymptotic expression for the minimal eigenvalues of a Toeplitz matrix with a symbolwhich is periodic, even and derivable on $[0, 2\pi[$. Next we prove that a Toeplitz band matrix with a symbol without zeros on the united circle is invertible with an inverse which is essentially a band matrix. As a consequence of this last statement we give an asymptotic estimation for the entries of the inverse of a Toeplitz matrix with a regular symbol.

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Philippe Rambour. 2015-12-14. Expression asymptotique des valeurs propres d'une matrice de Toeplitz \`a symbole r\'eel. https://arxiv.org/abs/1512.04296

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