{ "id": "2311.15998", "version": "v1", "published": "2023-11-27T16:46:02.000Z", "updated": "2023-11-27T16:46:02.000Z", "title": "Beglund-Hübsch transpose and Einstein metrics on rational homology 7-spheres", "authors": [ "Jaime Cuadros Valle", "Ralph R. Gomez", "Joe Lope Vicente" ], "comment": "24 pages, 1 table", "categories": [ "math.DG" ], "abstract": "We show that links of invertible polynomials coming from the Johnson and Koll\\'ar list of K\\\"ahler-Einstein 3-folds that are rational homology 7-spheres remain rational homology 7-spheres under the so-called Berglund-H\\\"ubsch (BH) transpose rule coming from classical mirror symmetry constructions. Actually, the BH-transpose rule produces twins, that is, links with same degree, Milnor number and homology H_3, with the exception of iterated Thom-Sebastiani sums of singularities of chain and cycle type, where the torsion and the Milnor number may vary. This BH-transpose rule not only gives a framework to better understand the existence of SasakiEinstein twins but also gives a mechanism for producing new examples of Sasaki-Einstein twins in the rational homology 7 -sphere setting. We also give reasonable conditions for a Sasaki-Einstein rational homology 7-sphere to remain Sasaki-Einstein under the BH-transpose rule. In particular, we found 75 new examples of Sasaki-Einstein rational homology 7-spheres arising as links of not well-formed hypersurface singularities.", "revisions": [ { "version": "v1", "updated": "2023-11-27T16:46:02.000Z" } ], "analyses": { "subjects": [ "53C25", "57R60" ], "keywords": [ "einstein metrics", "beglund-hübsch transpose", "sasaki-einstein rational homology", "bh-transpose rule produces twins", "milnor number" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable" } } }