Estimating the concurrence for quantum states via symmetric measurements

• URL: http://arxiv.org/abs/2606.31010v2
• Date: Thu, 02 Jul 2026 00:13:31 GMT
• Title: Estimating the concurrence for quantum states via symmetric measurements
• Abstract summary: We derive improved lower bounds of concurrence induced by symmetric measurements.<n>We resolve a related inequality conjecture, which implies that numerous previous results based on symmetric measurements are strictly stronger than the one based on realignment.
• Score: 10.749012906336034
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We derive improved lower bounds of concurrence induced by symmetric measurements, which retains experimental feasibility without state tomography. More importantly, we resolve a related inequality conjecture, which implies that numerous previous results based on symmetric measurements are strictly stronger than the one based on realignment. In addition, we also present a lower bound of genuine tripartite entanglement concurrence based on symmetric measurements.

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