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Asymptotic expansion of the eigenvalues of a Toeplitz matrix with a real symbol

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 نشر من قبل Philippe Rambour
 تاريخ النشر 2021
  مجال البحث
والبحث باللغة English
 تأليف Philippe Rambour




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Asymptotic expansion of the eigenvalues of a Toeplitz matrix with real symbol. This work provides two results obtained as a consequence of an inversion formula for Toeplitz matrices with real symbol. First we obtain an symptotic expression for the minimal eigenvalues of a Toeplitz matrix with a symbol which is periodic, even and derivable on $[0, 2pi[$. 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 Toplitz matrix with a regular symbol.

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