{ "id": "1305.6100", "version": "v4", "published": "2013-05-27T03:34:47.000Z", "updated": "2015-07-12T18:34:05.000Z", "title": "The homology of $\\mathrm{tmf}$", "authors": [ "Akhil Mathew" ], "comment": "30 pages; 3 figures. Submitted version. Comments always welcome", "categories": [ "math.AT", "math.AG" ], "abstract": "We compute the mod $2$ homology of the spectrum $\\mathrm{tmf}$ of topological modular forms by proving a 2-local equivalence $\\mathrm{tmf} \\wedge DA(1) \\simeq \\mathrm{tmf}_1(3) \\simeq BP\\left \\langle 2\\right\\rangle$, where $DA(1)$ is an eight cell complex whose cohomology \"doubles\" the subalgebra $\\mathcal{A}(1)$ of the Steenrod algebra generated by $\\mathrm{Sq}^1$ and $\\mathrm{Sq}^2$. To do so, we give, using the language of stacks, a modular description of the elliptic homology of $DA(1)$ via level three structures. We briefly discuss analogs at odd primes and recover the stack-theoretic description of the Adams-Novikov spectral sequence for $\\mathrm{tmf}$.", "revisions": [ { "version": "v3", "updated": "2013-11-20T14:40:15.000Z", "abstract": "We compute the mod 2 homology of the spectrum $\\mathrm{tmf}$ of topological modular forms by proving a 2-local equivalence $\\mathrm{tmf} \\wedge DA(1) \\simeq BP\\left\\langle 2\\right\\rangle$, where $DA(1)$ is an eight cell complex whose cohomology \"doubles\" the subalgebra $\\mathcal{A}(1)$ of the Steenrod algebra generated by $\\mathrm{Sq}^{1}$ and $\\mathrm{Sq}^{2}$. To do so, we give, with use of the language of stacks, a modular description of the elliptic homology of $DA(1)$ via level three structures. We briefly discuss analogs at odd primes and recover the stack-theoretic description of the Adams-Novikov spectral sequence for $\\mathrm{tmf}$.", "comment": "50 pages; 5 figures. Comments welcome. 5/30/13: several minor corrections and additional remarks added; 11/20/13: fixed LaTeX errors in abstract", "journal": null, "doi": null }, { "version": "v4", "updated": "2015-07-12T18:34:05.000Z" } ], "analyses": { "keywords": [ "adams-novikov spectral sequence", "cell complex", "modular description", "topological modular forms", "elliptic homology" ], "note": { "typesetting": "LaTeX", "pages": 30, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1305.6100M" } } }