Pub Date : 2024-05-07DOI: 10.1515/crelle-2024-0024
Nils Matthes, Morten S. Risager
We determine the asymptotic distribution of Manin’s iterated integrals of length at most 2. For all lengths, we compute all the asymptotic moments. We show that if the length is at least 3, these moments do in general not determine a unique distribution.
{"title":"The distribution of Manin’s iterated integrals of modular forms","authors":"Nils Matthes, Morten S. Risager","doi":"10.1515/crelle-2024-0024","DOIUrl":"https://doi.org/10.1515/crelle-2024-0024","url":null,"abstract":"\u0000 We determine the asymptotic distribution of Manin’s iterated integrals of length at most 2.\u0000For all lengths, we compute all the asymptotic moments.\u0000We show that if the length is at least 3, these moments do in general not determine a unique distribution.","PeriodicalId":508691,"journal":{"name":"Journal für die reine und angewandte Mathematik (Crelles Journal)","volume":"24 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141005656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-24DOI: 10.1515/crelle-2024-0022
Robert Haslhofer
We introduce a classification conjecture for κ-solutions in 4d Ricci flow. Our conjectured list includes known examples from the literature, but also a new one-parameter family of ℤ 2 2 × O 3 {mathbb{Z}_{2}^{2}timesmathrm{O}_{3}} -symmetric bubble-sheet ovals that we construct. We observe that some special cases of the conjecture follow from recent results in the literature. We also introduce a stronger variant of the classification conjecture for ancient asymptotically cylindrical 4d Ricci flows, which does not assume smoothness and nonnegative curvature operator a priori. Assuming this stronger variant holds true, we establish a canonical neighborhood theorem for 4d Ricci flow through cylindrical singularities, which shares some elements in common with Perelman’s canonical neighborhood theorem for 3d Ricci flow as well as the mean-convex neighborhood theorem for mean curvature flow through neck-singularities. Finally, we argue that quotient-necks lead to new phenomena, and sketch an example of non-uniqueness for 4d Ricci flow through singularities.
{"title":"On κ-solutions andbreak canonical neighborhoods in 4d Ricci flow","authors":"Robert Haslhofer","doi":"10.1515/crelle-2024-0022","DOIUrl":"https://doi.org/10.1515/crelle-2024-0022","url":null,"abstract":"\u0000 We introduce a classification conjecture for κ-solutions in 4d Ricci flow. Our conjectured list\u0000includes known examples from the literature, but also a new one-parameter family of \u0000 \u0000 \u0000 \u0000 \u0000 ℤ\u0000 2\u0000 2\u0000 \u0000 ×\u0000 \u0000 O\u0000 3\u0000 \u0000 \u0000 \u0000 \u0000 {mathbb{Z}_{2}^{2}timesmathrm{O}_{3}}\u0000 \u0000 -symmetric bubble-sheet ovals that we construct. We observe that some special cases of the conjecture follow from recent results in the literature. We also introduce a stronger variant of the classification conjecture for ancient asymptotically cylindrical 4d Ricci flows, which does not assume smoothness and nonnegative curvature operator a priori. Assuming this stronger variant holds true, we establish a canonical neighborhood theorem for 4d Ricci flow through cylindrical singularities, which shares some elements in common with Perelman’s canonical neighborhood theorem for 3d Ricci flow as well as the mean-convex neighborhood theorem for mean curvature flow through neck-singularities. Finally, we argue that quotient-necks lead to new phenomena, and sketch an example of non-uniqueness for 4d Ricci flow through singularities.","PeriodicalId":508691,"journal":{"name":"Journal für die reine und angewandte Mathematik (Crelles Journal)","volume":"50 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140663008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}