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تسجيل مستخدم جديدZariski Density and Computing in Arithmetic Groups
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For $n > 2$, let $Gamma$ denote either $SL(n, Z)$ or $Sp(n, Z)$. We give a practical algorithm to compute the level of the maximal principal congruence subgroup in an arithmetic group $Hleq Gamma$. This forms the main component of our methods for computing with such arithmetic groups $H$. More generally, we provide algorithms for computing with Zariski dense groups in $Gamma$. We use our GAP implementation of the algorithms to solve problems that have emerged recently for important classes of linear groups.
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