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arXiv · 2305.17909

The mass of shifted lattices and class numbers of inhomogeneous quadratic polynomials

Kathrin Bringmann·Zilong He·Ben Kane
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Abstract

In this paper, we investigate class numbers of shifted quadratic lattices $L+\frac{\boldsymbol{u}}{c}$ with $\boldsymbol{u}\in L$ and odd conductor $c\in \mathbb{N}$. For a lattice $L$ whose genus only contains one class, we determine a lower bound for the number of classes in the genus of $L+\frac{\boldsymbol{u}}{c}$ depending on $c$. As a result, we obtain an explicit bound $c_0$ such that any such shifted lattice with one class in its genus must have conductor smaller than $c_0$, restricting the possible choices of such $L+\frac{\boldsymbol{u}}{c}$ to a finite set.

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Kathrin Bringmann, Zilong He, Ben Kane. 2023-05-29. The mass of shifted lattices and class numbers of inhomogeneous quadratic polynomials. https://arxiv.org/abs/2305.17909

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