$AA^H$ and $A^HA$ has same eigen values and any else they don't share is zero
55377
Non-zero eigenvalues of $AA^T$ and $A^TA$
61538
Given a square matrix $A$, both $AA^T$ and $A^TA$ are symmetric
18282
Finding the minimal polynomial, the eigenvalues, and the characteristic polynomial of $T(A)=A+A^t$
110672
Is it true that $aH = bH$ iff $ab^{-1} \in H$
56727
Odd-dimensional complex skew-symmetric matrix has eigenvalue $0$
158205
If $A+A^T$ is negative definite, then the eigenvalues of $A$ have negative real parts?
90064
What does it mean when Mathematica returns a zero "eigenvector"?
131844
When does $(e^a)^b = e^{ab}$ hold?
10828
If $A^2 = I$, then $A$ is diagonalizable, and is $I$ if $1$ is its only eigenvalue
119387
If $A$ is any matrix then $A^*A$ and $AA^*$ are Hermitian with non-negative eigenvalues
82291
$T$ has no eigen-values
43913
Prove that if $A^*+A=AA^*$ then $A$ is normal
54099
What are the eigenvalues of $\operatorname{ad}x$?
106986
Eigenvalues of $AB$ and $BA$
146316
what is no. of positive eigen value of symmetric matrix A with some given relationship
104424
If each eigenvalueof $A$ is either $+1$ or $-1$ $ \Rightarrow$ $A$ is similar to ${A^{ - 1}}$
49158
Multiplicity of eigenvalues