Loading Discussion on answer by Surb: Using the divergence theorem to prove that $\frac{1}{|B_R(0)|} \int_{B_R(0)} M \textbf{y} . \textbf{y} dy = \frac{R^2}{ n + 2} \text{trace}(M)$
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Discussion on answer by Surb: Using the divergence theorem to prove that $\frac{1}{|B_R(0)|} \int_{B_R(0)} M \textbf{y} . \textbf{y} dy = \frac{R^2}{ n + 2} \text{trace}(M)$