Projection operator onto spin-S eigenspaces of total and orbital angular momenta

• URL: http://arxiv.org/abs/2605.27637v1
• Date: Tue, 26 May 2026 19:55:59 GMT
• Title: Projection operator onto spin-S eigenspaces of total and orbital angular momenta
• Abstract summary: The Frobenius covariant is used to construct a projection operator onto the spin-S eigenspaces.<n>A correspondence is established with Villars' angular momentum projection, used in nuclear studies.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The Frobenius covariant is used to construct a projection operator onto the spin-S eigenspaces associated with the squares of the total and orbital angular momenta. The covariant admits two equivalent representations: as a polynomial in powers of the scalar product of the spin and orbital angular momentum operators, and as a finite expansion in terms of their respective polarization operators. A correspondence is established with Villars' angular momentum projection, used in nuclear structure studies.

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