Abstract
This paper studies classical weight modules over the \(\imath \)quantum group \(\textbf{U}^{\imath }\) of type AI. We introduce the notion of based \(\textbf{U}^{\imath }\)-modules by generalizing the notion of based modules over quantum groups (quantized enveloping algebras). We prove that each finite-dimensional irreducible classical weight \(\textbf{U}^{\imath }\)-module with integer highest weight is a based \(\textbf{U}^{\imath }\)-module. As a byproduct, a new combinatorial formula for the branching rule from \(\mathfrak {sl}_n\) to \(\mathfrak {so}_n\) is obtained.
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The author thanks anonymous referees for helpful comments. This work was supported by JSPS KAKENHI Grant Number JP20K14286.
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Watanabe, H. Based modules over the \(\imath \)quantum group of type AI. Math. Z. 303, 43 (2023). https://doi.org/10.1007/s00209-022-03189-z
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DOI: https://doi.org/10.1007/s00209-022-03189-z