# The moduli stack of $G$-bundles

@article{Wang2011TheMS, title={The moduli stack of \$G\$-bundles}, author={Jonathan Wang}, journal={arXiv: Algebraic Geometry}, year={2011} }

In this paper, we give an expository account of the geometric properties of the moduli stack of $G$-bundles. For $G$ an algebraic group over a base field and $X \to S$ a flat, finitely presented, projective morphism of schemes, we give a complete proof that the moduli stack $Bun_G$ is an algebraic stack locally of finite presentation over $S$ with schematic, affine diagonal. In the process, we prove some properties of $BG$ and Hom stacks. We then define a level structure on $Bun_G$ to provide…

## 27 Citations

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