On the Multiplicities of Eigenvalues of a Hermitian Matrix Whose Graph Is a Tree
نویسندگان
چکیده
A different approach is given to recent results due mainly to R.C. Johnson and A. Leal Duarte on the multiplicities of eigenvalues of a Hermitian matrix whose graph is a tree. The technics developed are based on some results of matchings polynomials and use a work by O.L. Heilmann and E.H. Lieb on an apparently unrelated topic.
منابع مشابه
Interlacing Properties for Hermitian Matrices Whose Graph is a Given Tree
We extend some interlacing properties of the eigenvalues of tridiagonal matrices to Hermitian matrices whose graph is a tree. We also give a graphical interpretation of the results. We use the work on matchings polynomials by O.L. Heilmann and E.H. Lieb.
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