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arXiv · 1704.01229

Local Operations and Completely Positive Maps in Algebraic Quantum Field Theory

Yuichiro Kitajima
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Abstract

Einstein introduced the locality principle which states that all physical effect in some finite space-time region does not influence its space-like separated finite region. Recently, in algebraic quantum field theory, R\'{e}dei captured the idea of the locality principle by the notion of operational separability. The operation in operational separability is performed in some finite space-time region, and leaves unchanged the state in its space-like separated finite space-time region. This operation is defined with a completely positive map. In the present paper, we justify using a completely positive map as a local operation in algebraic quantum field theory, and show that this local operation can be approximately written with Kraus operators under the funnel property.

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Yuichiro Kitajima. 2017-04-05. Local Operations and Completely Positive Maps in Algebraic Quantum Field Theory. https://arxiv.org/abs/1704.01229

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