摘要
令g是任意Kac-Moody代数,其Cartan子代数为h.本文确定了在U(h)上限制是秩1自由的g-模组成的模范畴.确切地讲,这个模范畴是非空的当且仅当g是A_l型或是C_l型的,其中l是正整数.
Let g be an arbitrary Kac-Moody algebra with a Cartan subalgebra h. In this paper, we determine the category of g-modules that are free U(h)-modules of rank 1. More precisely, this category of g-modules is not empty if and only if g is of type A_l or C_l for any positive integer l.
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