# Can eigenvectors not be orthogonal?

## Can eigenvectors not be orthogonal?

In general, for any matrix, the eigenvectors are NOT always orthogonal. But for a special type of matrix, symmetric matrix, the eigenvalues are always real and the corresponding eigenvectors are always orthogonal.

## Are eigenvectors of a matrix orthogonal?

A basic fact is that eigenvalues of a Hermitian matrix A are real, and eigenvectors of distinct eigenvalues are orthogonal. Two complex column vectors x and y of the same dimension are orthogonal if xHy = 0.

How do you know if an eigenvector is orthogonal?

If v is an eigenvector for AT and if w is an eigenvector for A, and if the corresponding eigenvalues are different, then v and w must be orthogonal. Of course in the case of a symmetric matrix, AT = A, so this says that eigenvectors for A corresponding to different eigenvalues must be orthogonal.

### Can a non symmetric matrix have orthogonal eigenvectors?

Vector x is a right eigenvector, vector y is a left eigenvector, corresponding to the eigenvalue λ, which is the same for both eigenvectors. As opposed to the symmetric problem, the eigenvalues a of non-symmetric matrix do not form an orthogonal system.

### Do eigenvectors form an orthogonal basis?

In the special case where all the eigenvalues are different (i.e. all multiplicities are 1) then any set of eigenvectors corresponding to different eigenvalues will be orthogonal.

Do all matrices have orthogonal eigenvectors?

The statement is imprecise: eigenvectors corresponding to distinct eigenvalues of a symmetric matrix must be orthogonal to each other. Eigenvectors corresponding to the same eigenvalue need not be orthogonal to each other.

## Can non-symmetric matrix be orthogonal?

The answer is NO. A matrix B is symmetric means that its transposed matrix is itself. The matrix B is orthogonal means that its transpose is its inverse. So an orthogonal matrix is necessarily invertible whereas that is not necessary for a symmetric matrix.

Can a non-symmetric matrix be orthogonally diagonalized?

Equivalently, a square matrix is symmetric if and only if there exists an orthogonal matrix S such that ST AS is diagonal. That is, a matrix is orthogonally diagonalizable if and only if it is symmetric. 3. A non-symmetric matrix which admits an orthonormal eigenbasis.

### What is orthonormal eigenvectors?

The orthonormal eigenvectors are the columns of the unitary matrix U−1 when a Hermitian matrix H is transformed to the diagonal matrix UHU−1. From: Mathematical Methods for Physicists (Seventh Edition), 2013.

### Can every matrix be orthogonally diagonalizable?

Therefore, every symmetric matrix is diagonalizable because if U is an orthogonal matrix, it is invertible and its inverse is UT. In this case, we say that A is orthogonally diagonalizable. Therefore every symmetric matrix is in fact orthogonally diagonalizable.