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arXiv · 2503.24068

A Quantum Energy Inequality for a Non-commutative QFT

Harald Grosse·Albert Much
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Abstract

We present a quantum energy inequality (QEI) for quantum field theories formulated in non-commutative spacetimes, extending fundamental energy constraints to this generalized geometric framework. By leveraging operator-theoretic methods inspired by the positivity map of Waldmann et al. \cite{waldmannpos}, we construct linear combinations of deformed operators that generalize the commutative spacetime techniques of Fewster et al., \cite{Few98}. These non-commutative analogs enable us the derivation of a lower bound on the deformed averaged energy density, ensuring the stability of the underlying quantum field theory. Our result establishes rigorous constraints on the expectation values of the deformed (non-commutative) energy density, reinforcing the physical consistency of non-commutative models while preserving core principles of quantum field theory.

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Harald Grosse, Albert Much. 2025-03-31. A Quantum Energy Inequality for a Non-commutative QFT. https://doi.org/10.1007/jhep08(2025)190

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