Gyration Tensor - Diagonalization

Diagonalization

Since the gyration tensor is a symmetric 3x3 matrix, a Cartesian coordinate system can be found in which it is diagonal


\mathbf{S} = \begin{bmatrix}
\lambda_{x}^{2} & 0 & 0 \\
0 & \lambda_{y}^{2} & 0 \\
0 & 0 & \lambda_{z}^{2}
\end{bmatrix}

where the axes are chosen such that the diagonal elements are ordered . These diagonal elements are called the principal moments of the gyration tensor.

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