Consider a $2n-$dimensional symmetric random matrix $M$ of form, $M = \begin{bmatrix} aa^T & ab^T \\ ba^T & bb^T \end{bmatrix}$ where $a$ and $b$ are $n$ dimensional random vectors.
- Are there conditions known on $a$ and $b$ s.t we have the following property : that for any $\hat{x} \in S^{2n-1}$ and any $R \in SO(2n)$, $\Vert M \hat{x} \Vert$ be equidistributed as $\Vert (R M R^T)\hat{x} \Vert$ ?