{"title":"通过特殊化实现库默尔曲面在特征二中的去奇点化","authors":"Alvaro Gonzalez-Hernandez","doi":"arxiv-2409.04532","DOIUrl":null,"url":null,"abstract":"We study the birational geometry of the Kummer surfaces associated to the\nJacobian varieties of genus two curves, with a particular focus on fields of\ncharacteristic two. In order to do so, we explicitly compute a projective\nembedding of the Jacobian of a general genus two curve and, from this, we\nconstruct its associated Kummer surface. This explicit construction produces a\nmodel for desingularised Kummer surfaces over any field of characteristic not\ntwo, and specialising these equations to characteristic two provides a model of\na partial desingularisation. Adapting the classic description of the Picard\nlattice in terms of tropes, we also describe how to explicitly find completely\ndesingularised models of Kummer surfaces whenever the $p$-rank is not zero. In\nthe final section of this paper, we compute an example of a Kummer surface with\neverywhere good reduction over a quadratic number field, and draw connections\nbetween the models we computed and a criterion that determines when a Kummer\nsurface has good reduction at two.","PeriodicalId":501064,"journal":{"name":"arXiv - MATH - Number Theory","volume":"65 4 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Explicit desingularisation of Kummer surfaces in characteristic two via specialisation\",\"authors\":\"Alvaro Gonzalez-Hernandez\",\"doi\":\"arxiv-2409.04532\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We study the birational geometry of the Kummer surfaces associated to the\\nJacobian varieties of genus two curves, with a particular focus on fields of\\ncharacteristic two. In order to do so, we explicitly compute a projective\\nembedding of the Jacobian of a general genus two curve and, from this, we\\nconstruct its associated Kummer surface. This explicit construction produces a\\nmodel for desingularised Kummer surfaces over any field of characteristic not\\ntwo, and specialising these equations to characteristic two provides a model of\\na partial desingularisation. Adapting the classic description of the Picard\\nlattice in terms of tropes, we also describe how to explicitly find completely\\ndesingularised models of Kummer surfaces whenever the $p$-rank is not zero. In\\nthe final section of this paper, we compute an example of a Kummer surface with\\neverywhere good reduction over a quadratic number field, and draw connections\\nbetween the models we computed and a criterion that determines when a Kummer\\nsurface has good reduction at two.\",\"PeriodicalId\":501064,\"journal\":{\"name\":\"arXiv - MATH - Number Theory\",\"volume\":\"65 4 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-09-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - MATH - Number Theory\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2409.04532\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - MATH - Number Theory","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2409.04532","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Explicit desingularisation of Kummer surfaces in characteristic two via specialisation
We study the birational geometry of the Kummer surfaces associated to the
Jacobian varieties of genus two curves, with a particular focus on fields of
characteristic two. In order to do so, we explicitly compute a projective
embedding of the Jacobian of a general genus two curve and, from this, we
construct its associated Kummer surface. This explicit construction produces a
model for desingularised Kummer surfaces over any field of characteristic not
two, and specialising these equations to characteristic two provides a model of
a partial desingularisation. Adapting the classic description of the Picard
lattice in terms of tropes, we also describe how to explicitly find completely
desingularised models of Kummer surfaces whenever the $p$-rank is not zero. In
the final section of this paper, we compute an example of a Kummer surface with
everywhere good reduction over a quadratic number field, and draw connections
between the models we computed and a criterion that determines when a Kummer
surface has good reduction at two.