$\mathsf{BQP} \subseteq \mathsf{IP}$ Does Not Relativize

This paper resolves a long-standing open question by constructing an oracle relative to which $\mathsf{BQP} \not\subseteq \mathsf{IP}$, using the Forrelation problem and novel structural results to demonstrate that classical interactive proofs cannot efficiently verify quantum computation in a relativizing setting.

Original authors: Adam Bouland, Andrew Huang, Anand Natarajan, Itay Shalit, Avishay Tal