Are rotation matrices tensors?

Question

Are rotation matrices tensors? If no, why? I'm not sure about it, for example considering the $z$-axis rotation matrix when I rotate the coordinate system the rotation matrix around the old $z$-axis change form.

Matrices are never tensors. Some tensors can be represented by matrices. Tensors are multilinear maps and not matrices — Mathphys meister, Oct 13 '19 at 16:45

score 1 · Accepted Answer · answered Oct 13 '19 at 11:28

1

No, for an Euclidean 3D space the rotations (and translations) are maps between reference frames, while tensors are independent of reference frames. See also my related Phys.SE answer here in the context of SR.

answered Oct 13 '19 at 11:28

Qmechanic

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Are rotation matrices tensors?

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