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Construction of Some Generalised Modular Symbols

B. Speh·T. N. Venkataramana
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Abstract

We give a criterion for the non-vanishing of some generalised modular symbols. The criterion is in terms of the non-vanishing of some classes on the compact dual of the locally symmetric manifold. As an application, we construct non-zero modular symbols on SL(2n) over an imaginary quadratic extension of $\Q$, which turn out to be ghost classes.

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B. Speh, T. N. Venkataramana. 2004-09-21. Construction of Some Generalised Modular Symbols. https://arxiv.org/abs/math/0409376

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