Noetherianity for powers of algebraic representations
Alessandro Danelon
TL;DR
This work establishes topological Noetherianity for powers of algebraic representations under the action of the infinite symmetric group together with classical groups. By first linking Noetherianity across $\operatorname{GL}$, $\operatorname{O}$, and $\operatorname{Sp}$ via a group-homomorphism framework, the authors reduce the problem to proving the GL case, then extend the argument to the orthogonal and symplectic settings. The core method combines orbit-closure techniques and a $Z^+$-construction to transfer Noetherianity from finite-level truncations $(M\oplus E)^{\mathbb{N}}$ to the infinite-dimensional setting, building on and generalizing prior work of Draisma, Eggermont–Snowden, and Chiu–Danelon–Draisma–Eggermont–Farooq. The results broaden the class of tensor varieties known to be topologically Noetherian under $\operatorname{Sym} \times G$ actions and connect to the broader program on Noetherianity in infinite-dimensional representation theory. This has potential implications for understanding stability phenomena in tensor categories and invariant theory for infinite-dimensional group actions.
Abstract
Powers of a polynomial $\operatorname{GL}$-representation are topologically Noetherian under the action of $\operatorname{Sym} \times \operatorname{GL}$. We show that this result extends to powers of algebraic representations of the orthogonal and the symplectic groups. This work is a natural follow-up to arXiv:2212.05790 and to arXiv:1708.06420.
