Optimality of Gaussian Entanglement of Formation

Gerardo Adesso

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arXiv · 2608.01909

Optimality of Gaussian Entanglement of Formation

Gerardo Adesso

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Abstract

We prove that the entanglement of formation of every two-mode Gaussian state coincides with its Gaussian restriction, solving a longstanding open problem in continuous variable quantum information theory. The key result is a sharp affine relation between entanglement and a generalized Einstein-Podolsky-Rosen observable, valid for arbitrary pure two-mode states, including non-Gaussian ones. Our result extends to bisymmetric multimode Gaussian states, and also provides a measurable lower bound on the entanglement of formation of arbitrary non-Gaussian states.

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Gerardo Adesso. 2026-08-03. Optimality of Gaussian Entanglement of Formation. https://arxiv.org/abs/2608.01909

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