Aaronson–Ambainis conjecture (dense-domain query upper bound)
Establish that for any function f defined on a dense subset S⊆{−1,1}^N with |S|≥c·2^N, there exists a deterministic classical decision tree making poly(\tilde{\deg}(f), 1/α, 1/c) queries that computes f(X) on at least a 1−α fraction of inputs X∈S.
References
Conjecture [Aaronson-Ambainis conjecture; Conjecture $7.1$ in] Let $S\subseteq {-1,1}{N}$ with $|S|\geq c2{N}$, and let $f:S \rightarrow {-1,1}$. Then there exists a deterministic classical algorithm that makes $((f),1/\alpha,1/c)$ queries, and that computes $f(X)$ on at least a $1-\alpha$ fraction of $X\in S$.
— From Promises to Totality: A Framework for Ruling Out Quantum Speedups
(2603.29256 - Huffstutler et al., 31 Mar 2026) in Subsubsection: Perturbing approximate polynomials (Towards general partial function completions)