Unlike singular values, they are only defined for square matrices.
The values of the multiset of these things associated to the Frobenius automorphism on a field of prime power order are the roots of unity. These things are bounded by Gerschgorin circles. For a given Jordan block, the diagonal consists of one of these numbers repeated. The multiset of them associated to a linear operator is called the operator's spectrum. These quantities are either 0 or 1 for a projection operator, and are real for a self-adjoint operator. Unlike singular values, they are only defined for square matrices. These scalars are the solutions to a matrix's characteristic equation, and the product of all of them for a matrix equals the determinant. For 10 points, name these scalars that satisfy the equation "A v equals lambda v", and which are associated to eigenvectors.
The values of the multiset of these things associated to the Frobenius automorphism on a field of prime power order are the roots of unity.
eigenvalues [or characteristic values; prompt on "lambda"]