Unified approach to reciprocal matrices with Kippenhahn curves containing elliptical components

Muyan Jiang, Ilya M. Spitkovsky

Reciprocal matrices are tridiagonal matrices $(a_{ij}{)}_{i,j=1}^n$ with constant main diagonal and such that $a_{i,i+1}{a}_{i+1,i}=1$ for $i=1,\dots ,n-1$. For these matrices, criteri…