Abstract
We consider the compact quantum group \(U_q(2)\) for \(q\in \mathbb {C}\setminus \{0\}\) with \(|q|\ne 1\), and decompose the tensor product of two irreducible representations into irreducible components. The decomposition is realized in terms of a basis of homogeneous polynomials in four variables involving the matrix elements of the irreducible representations of \(U_q(2)\). Then, we compute the Clebsch–Gordan coefficients in terms of the q-hypergeometric series \({}_3\phi _2\). When q is real, the Clebsch–Gordan coefficients are real and its expression can be written in terms of the q-Hahn polynomial \({\mathscr {Q}}_n(x;a,b,N|q^2)\).
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The first author, Satyajit Guin acknowledges the support of SERB Grant MTR/2021/000818 and the second author, Bipul Saurabh acknowledges the support of SERB Grant SRG/2020/000252.
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Communicated by S Viswanath.
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Guin, S., Saurabh, B. On the Clebsch–Gordan coefficients for the quantum group \({\varvec{U}}_{\varvec{q}}\varvec{(2)}\). Proc Math Sci 133, 44 (2023). https://doi.org/10.1007/s12044-023-00762-2
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DOI: https://doi.org/10.1007/s12044-023-00762-2