# On Rotations as Spin Matrix Polynomials

@article{Curtright2014OnRA, title={On Rotations as Spin Matrix Polynomials}, author={Thomas L. Curtright and Thomas van Kortryk}, journal={arXiv: Mathematical Physics}, year={2014} }

Recent results for rotations expressed as polynomials of spin matrices are derived here by elementary differential equation methods. Structural features of the results are then examined in the framework of biorthogonal systems, to obtain an alternate derivation. The central factorial numbers play key roles in both derivations.

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Group elements of SU(2) are expressed in closed form as finite polynomials of the Lie algebra generators, for all definite spin representations of the rotation group. The simple explicit result…

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