One-half reflected entropy is not a lower bound for entanglement of
purification
- URL: http://arxiv.org/abs/2309.02506v2
- Date: Mon, 22 Jan 2024 19:14:15 GMT
- Title: One-half reflected entropy is not a lower bound for entanglement of
purification
- Authors: Josiah Couch, Phuc Nguyen, Sarah Racz, Georgios Stratis, Yuxuan Zhang
- Abstract summary: We prove that the entanglement of purification $E_p(A:B)$ is bounded below by half of the $q$-R'enyi reflected entropy $S_R(q)(A:B)$ for all $qgeq2$.
This result does not preclude the possibility that restricted sets of states, such as CFT states with semi-classical gravity duals, could obey the bound in question.
- Score: 6.578021055948705
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In recent work, Akers et al. proved that the entanglement of purification
$E_p(A:B)$ is bounded below by half of the $q$-R\'enyi reflected entropy
$S_R^{(q)}(A:B)$ for all $q\geq2$, showing that $E_p(A:B) = \frac{1}{2}
S_R^{(q)}(A:B)$ for a class of random tensor network states. Naturally, the
authors raise the question of whether a similar bound holds at $q = 1$. Our
work answers that question in the negative by finding explicit
counter-examples, which we arrive at through numerical optimization.
Nevertheless, this result does not preclude the possibility that restricted
sets of states, such as CFT states with semi-classical gravity duals, could
obey the bound in question.
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