aiqbench analysis
This paper establishes a fundamental separation between the complexity classes QMA and QMA(2) using a classical oracle, advancing our understanding of quantum proof verification limits. The result hinges on constructing specific Hamiltonian problems where entangled states behave distinctly from product states under signed edge constraints. This theoretical breakthrough clarifies the power of multiple unentangled witnesses in quantum computation without relying on AI or machine learning techniques.
A classical oracle separation between QMA and QMA(2)
arXiv:2610.06760v1 Announce Type: new Abstract: We exhibit a classical oracle relative to which QMA \neq QMA(2). The separation is based on a separable Hamiltonian problem defined by signed edge constraints on a graph. The YES instances have zero-energy product states, while the NO instances, constructed using the antisymmetric subspace, have entangled zero-energy states but no low-energy product states. For the QMA lower bound, we use compressed-oracle techniques to track the information learned by a quantum computation making few queries to a YES instance. The key step is to map the resulting superpositions of partial oracle records to the NO family without significantly changing the verifier's behavior.
Abstract:We exhibit a classical oracle relative to which QMA \neq QMA(2). The separation is based on a separable Hamiltonian problem defined by signed edge constraints on a graph. The YES instances have zero-energy product states, while the NO instances, constructed using the antisymmetric subspace, have entangled zero-energy states but no low-energy product states. For the QMA lower bound, we use compressed-oracle techniques to track the information learned by a quantum computation making few queries to a YES instance. The key step is to map the resulting superpositions of partial oracle records to the NO family without significantly changing the verifier's behavior.
arXiv:2610.06760 [quant-ph]
(or arXiv:2610.06760v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2610.06760 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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Full text under the publisher's open licence · 192 words
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