The symplectic holomorphic density property for Calogero-Moser spaces
Rafael B. Andrist, Gaofeng Huang
TL;DR
The paper defines and develops the symplectic holomorphic density property and the Hamiltonian holomorphic density property for Stein manifolds, and proves that Calogero–Moser spaces $\mathcal{C}_n$ possess both properties. By combining invariant theory of matrix tuples, rank-one reductions, and detailed bracket calculations, it is shown that a finite set of Hamiltonians ($\operatorname{tr} Y$, $\operatorname{tr} Y^2$, $\operatorname{tr} X^3$, $(\operatorname{tr} X)^2$) generates all holomorphic Hamiltonians on $\mathcal{C}_n$, enabling an Andersén–Lempert-type approximation of any symplectic holomorphic automorphism by complete flows. For $n=2$ and general $n$, the authors construct explicit generators and brackets, culminating in a full description of the identity component of the symplectic holomorphic automorphism group as the closure of flows from these Hamiltonians. The results connect Calogero–Moser spaces to Hilbert schemes and extend known density results from $T^*\mathbb{C}^n$ to a rich, higher-dimensional setting with strong transitivity properties.
Abstract
We introduce the symplectic holomorphic density property and the Hamiltonian holomorphic density property together with the corresponding version of Andersén-Lempert theory. We establish these properties for the Calogero-Moser space $\mathcal{C}_n$ of $n$ particles and describe its group of holomorphic symplectic automorphisms.
