# Extrapolated Quantum States, Void States, and a Huge Novel Class of   Distillable Entangled States

**Authors:** Michel Boyer, Aharon Brodutch, Tal Mor

arXiv: 1701.07757 · 2017-01-27

## TL;DR

This paper identifies a large class of separable and classical states that have distillable entangled or discordant states arbitrarily close to them, revealing new insights into quantum state boundaries and correlations.

## Contribution

It introduces a vast class of separable states with nearby distillable entanglement and extends the concept to classical states, providing constructive methods to find such states.

## Key findings

- Large class of separable states with nearby distillable entanglement
- All classical states have nearby discordant states
- Constructive method for finding epsilon-discordant states

## Abstract

A nice and interesting property of any pure tensor-product state is that each such state has distillable entangled states at an arbitrarily small distance $\epsilon$ in its neighborhood. We say that such nearby states are $\epsilon$-entangled, and we call the tensor product state in that case, a "boundary separable state", as there is entanglement at any distance from this "boundary". Here we find a huge class of separable states that also share that property mentioned above -- they all have $\epsilon$-entangled states at any small distance in their neighborhood. Furthermore, the entanglement they have is proven to be distillable. We then extend this result to the discordant/classical cut and show that all classical states (correlated and uncorrelated) have discordant states at distance $\epsilon$, and provide a constructive method for finding $\epsilon$-discordant states.

## Figures

2 figures with captions in the complete paper: https://tomesphere.com/paper/1701.07757/full.md

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Source: https://tomesphere.com/paper/1701.07757