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arXiv · 0907.4737

QIP = PSPACE

Rahul Jain·Zhengfeng Ji·Sarvagya Upadhyay·John Watrous
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Abstract

We prove that the complexity class QIP, which consists of all problems having quantum interactive proof systems, is contained in PSPACE. This containment is proved by applying a parallelized form of the matrix multiplicative weights update method to a class of semidefinite programs that captures the computational power of quantum interactive proofs. As the containment of PSPACE in QIP follows immediately from the well-known equality IP = PSPACE, the equality QIP = PSPACE follows.

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Rahul Jain, Zhengfeng Ji, Sarvagya Upadhyay, John Watrous. 2009-08-03. QIP = PSPACE. https://arxiv.org/abs/0907.4737

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