Solving quadratic equations using reduced unimodular quadratic forms
Solving quadratic equations using reduced unimodular quadratic forms
Let $Q$ be an $n\times n$ symmetric matrix with integral entries and with $\det Q \neq 0$, but not necesarily positive definite. We describe a generalized LLL algorithm to reduce this quadratic form. This algorithm either reduces the quadratic form or stops with some isotropic vector. It is proved to …