activity
20082025
most citedSingle-Class Genera of Positive Integral Lattices

15 citations · 17 across the 9 of their papers we have counts for

collaborators

10 papers

math.AG2025

On hyperbolic lattices whose reduced automorphism group is virtually abelian

Simon Brandhorst, Markus Kirschmer, Giacomo Mezzedimi

We give a classification of even integral lattices with virtually abelian reduced automorphism group. As a consequence, we complete the classification of K3 surfaces with virtually…

math.NT2024

Enumerating orders in number fields

Markus Kirschmer, Jürgen Klüners

We arrange the orders in an algebraic number field in a tree. This tree can be used to enumerate all orders of bounded index in the maximal order as well as the orders over some gi…

math.NT2022

Chow groups of one-dimensional noetherian domains

Markus Kirschmer, Jürgen Klüners

We discuss various connections between ideal classes, divisors, Picard and Chow groups of one-dimensional noetherian domains. As a result of these, we give a method to compute Chow…

math.NT2020

Spanning the isogeny class of a power of an ordinary elliptic curve over a finite field. Application to the number of rational points of curves of genus

Markus Kirschmer, Fabien Narbonne, Christophe Ritzenthaler +1

Let be an ordinary elliptic curve over a finite field and be a positive integer. Under some technical assumptions, we give an algorithm to span the isomorphism classes of p…

math.NT2019

Determinant groups of hermitian lattices over local fields

Markus Kirschmer

We describe the determinants of the automorphism groups of hermitian lattices over local fields. Using a result of G. Shimura, this yields an explicit method to compute the special…

math.NT2017★ 1 cited

Quaternary quadratic lattices over number fields

Markus Kirschmer, Gabriele Nebe

We relate proper isometry classes of maximal lattices in a totally definite quaternary quadratic space (V,q) with trivial discriminant to certain equivalence classes of ideals in t…

math.NT2016

One class genera of lattice chains over number fields

Markus Kirschmer, Gabriele Nebe

We classify all one-class genera of admissible lattice chains of length at least 2 in hermitian spaces over number fields.

math.NT2012★ 15 cited

Single-Class Genera of Positive Integral Lattices

David Lorch, Markus Kirschmer

We give an enumeration of all positive definite primitive Z-lattices in dimension >= 3 whose genus consists of a single isometry class. This is achieved by using bounds obtained fr…

math.GR2009★ 1 cited

Finite symplectic matrix groups

Markus Kirschmer

This paper classifies the maximal finite subgroups of Sp(2n,Q) for 1 <= n <= 11 up to conjugacy in GL(2n,Q).

math.NT2008

Algorithmic enumeration of ideal classes for quaternion orders

Markus Kirschmer, John Voight

We provide algorithms to count and enumerate representatives of the (right) ideal classes of an Eichler order in a quaternion algebra defined over a number field. We analyze the ru…