Work

A quantum oracle separation between QMA(2) and QMA

Year: 2026

Type: preprint

Abstract: We find a quantum oracle relative to which $\mathsf{QMA} \neq \mathsf{QMA}(2)$. As a consequence, we resolve the no-disentanglers conjecture of Watrous: for every $ε+δ<1$, any $(ε,δ)$-disentangler requires input size exponential in the number of output qubits. Our proof combines the unitarily invariant polynomial method of She and Yuen (ITCS '23) with a new construction based on the symmetric and antisymmetric subspace projectors, reducing the $\mathsf{QMA}$ lower bound to the approximate degree of $\mathrm{OR}$.

Source: arXiv (Cornell University)

DOI: 10.48550/arxiv.2609.02865

Authors: Bostanci, John, Grewal, Sabee, Haferkamp, Jonas, Huang, Andrew, Hwang, Yeongwoo, Natarajan, Anand, Nirkhe, Chinmay

Institutions: University of Washington, University of California, Berkeley, IBM (United States), Columbia University, Ruhr University Bochum, Harvard University

Language: English

Topic: Quantum Computing Algorithms and Architecture

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: green

OpenAlex ID: W7207781840

Cites: 26

Cited by: 3

Related to: 10