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However, calculating quantum discord involves optimization over measurements, which is computationally challenging and often infeasible. This raises the intriguing question of Gaussian extremality\u2014whether the quantum discord of a reference Gaussian state can provide a meaningful bound to the quantum discord of the original state. In this paper, we investigate this question by comparing the Gaussian discord of a reference Gaussian state with the quantum discord.<\/jats:p>","DOI":"10.1007\/s11128-025-04693-x","type":"journal-article","created":{"date-parts":[[2025,3,8]],"date-time":"2025-03-08T09:41:02Z","timestamp":1741426862000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Quantum discord is not extremalized by Gaussian states"],"prefix":"10.1007","volume":"24","author":[{"given":"Seungmin","family":"Lee","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8642-9104","authenticated-orcid":false,"given":"Changsuk","family":"Noh","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3870-5714","authenticated-orcid":false,"given":"Jiyong","family":"Park","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2025,3,8]]},"reference":[{"key":"4693_CR1","doi-asserted-by":"publisher","first-page":"865","DOI":"10.1103\/RevModPhys.81.865","volume":"81","author":"R Horodecki","year":"2009","unstructured":"Horodecki, R., Horodecki, P., Horodecki, M., Horodecki, K.: Quantum entanglement. 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