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arXiv · 2605.23824

The negativity core of a 1+1D massless scalar quantum field

Jason Pye·Atharva Hingane·Robert H. Jonsson
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Abstract

Vacuum entanglement is a fundamental feature of quantum field theory exhibiting rich structure that is not completely understood. Here, we provide a complete characterization of the entanglement between two bounded spacelike-separated regions in a (1+1)-dimensional free massless real scalar field. Employing Gaussian state methods, we analytically compute the logarithmic negativity and construct closed-form solutions for the localized modes carrying it, called negativity cores. These results deepen our understanding of quantum fields and suggest extensions to higher dimensions and fermionic fields.

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Jason Pye, Atharva Hingane, Robert H. Jonsson. 2026-05-22. The negativity core of a 1+1D massless scalar quantum field. https://arxiv.org/abs/2605.23824

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