What's the formula? - eigenvectors from eigenvalues

[Stephen Tashi]

Anyone know what result this article is talking about? https://www.theatlantic.com/science...-lead-striking-mathematical-discovery/602128/

 

[kith]

This one: https://arxiv.org/abs/1908.03795

 

[jedishrfu]

The idea is that the eigenvalues of a matrix A combined with the eigenvalues and eigenvectors of the submatrices of A can be used to compute the eigenvectors of A.

It reduces the complexity of eigenvector solving for large matrices but reducing the problem to smaller matrices and using the computed eigenvalues to aid in the solution.

I still haven't seen a numerical example though the graphic in The Atlantic article gives you an example to be completed by the reader.

 

[Robert M]

https://terrytao.wordpress.com/2019/08/13/eigenvectors-from-eigenvalues/#more-11249