We consider the problem of the explicit description of the gauge-invariant subspace of pure lattice gauge theories in the Hamiltonian formulation, where the gauge group is either a compact Lie group or a finite group. The latter case is particularly interesting for quantum simulation. A basis of states where configurations are grouped according to their holonomies is shown to have several advantages over other descriptions. Using this basis, we compute some properties of interest for some non-Abelian finite groups on small lattices, and in particular we examine the question of whether a certain ansatz introduced long ago is a good approximation for the ground state.

中文翻译：

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几乎规范不变的状态和杨米尔斯理论的基态

我们考虑哈密顿公式中纯格子规范理论的规范不变子空间的显式描述问题，其中规范群是紧李群或有限群。后一种情况对于量子模拟特别有趣。根据其完整性对配置进行分组的状态基础被证明比其他描述具有多个优点。使用这个基础，我们计算了小格上的一些非阿贝尔有限群的一些感兴趣的性质，特别是我们检查了很久以前引入的某个 ansatz 是否是基态的良好近似的问题。