{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:04:13Z","timestamp":1760058253995,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,18]],"date-time":"2025-03-18T00:00:00Z","timestamp":1742256000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Nature Science Foundation of China","doi-asserted-by":"publisher","award":["12171140"],"award-info":[{"award-number":["12171140"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>In this paper, we prove that the complex four dimensional compact holomorphic symplectic manifold we found earlier is not formal. This gives another strong consequence that it is not a topological K\u00e4hler manifold. We also conjecture that this is true for the higher dimensional ones.<\/jats:p>","DOI":"10.3390\/axioms14030226","type":"journal-article","created":{"date-parts":[[2025,3,18]],"date-time":"2025-03-18T10:43:51Z","timestamp":1742294631000},"page":"226","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Examples of Compact Simply Connected Holomorphic Symplectic Manifolds Which Are Not Formal"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0938-1669","authenticated-orcid":false,"given":"Daniel","family":"Guan","sequence":"first","affiliation":[{"name":"School of Mathematics and Statistics, Henan University, Kaifeng 475004, China"},{"name":"Department of Mathematics, University of California, Riverside, CA 92520, USA"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,18]]},"reference":[{"key":"ref_1","first-page":"295","article-title":"Compact Symplectic Solvmanifolds not Admitting Complex Structures","volume":"34","author":"Gray","year":"1990","journal-title":"Geometae Dedicata"},{"key":"ref_2","first-page":"467","article-title":"Some simple examples of symplectic manifolds","volume":"55","author":"Thurston","year":"1976","journal-title":"Proc. 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