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arXiv · hep-th/0604181

6J Symbols Duality Relations

L. Freidel·K. Noui·P. Roche
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Abstract

It is known that the Fourier transformation of the square of (6j) symbols has a simple expression in the case of su(2) and U_q(su(2)) when q is a root of unit. The aim of the present work is to unravel the algebraic structure behind these identities. We show that the double crossproduct construction H_1\bowtie H_2 of two Hopf algebras and the bicrossproduct construction H_2^{*}\lrbicross H_1 are the Hopf algebras structures behind these identities by analysing different examples. We study the case where D= H_1\bowtie H_2 is equal to the group algebra of ISU(2), SL(2,C) and where D is a quantum double of a finite group, of SU(2) and of U_q(su(2)) when q is real.

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L. Freidel, K. Noui, P. Roche. 2006-04-25. 6J Symbols Duality Relations. https://doi.org/10.1063/1.2803507

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