{"title":"论无限透镜空间与一般度不变空间乘积的模-2同调","authors":"Dang Vo Phuc","doi":"arxiv-2408.07485","DOIUrl":null,"url":null,"abstract":"Let $\\mathbb S^{\\infty}/\\mathbb Z_2$ be the infinite lens space. Denote the\nSteenrod algebra over the prime field $\\mathbb F_2$ by $\\mathscr A.$ It is\nwell-known that the cohomology $H^{*}((\\mathbb S^{\\infty}/\\mathbb Z_2)^{\\oplus\ns}; \\mathbb F_2)$ is the polynomial algebra $\\mathcal {P}_s:= \\mathbb F_2[x_1,\n\\ldots, x_s],\\, \\deg(x_i) = 1,\\, i = 1,\\, 2,\\ldots, s.$ The Kameko squaring\noperation $(\\widetilde {Sq^0_*})_{(s; N)}: (\\mathbb F_2\\otimes_{\\mathscr A}\n\\mathcal {P}_s)_{2N+s} \\longrightarrow (\\mathbb F_2\\otimes_{\\mathscr A}\n\\mathcal {P}_s)_{N}$ is indeed a valuable homomorphism for studying the\ndimension of the indecomposables $\\mathbb F_2\\otimes_{\\mathscr A} \\mathcal\n{P}_s,$ It has been demonstrated that this $(\\widetilde {Sq^0_*})_{(s; N)}$ is\nonto. Motivated by our previous work [J. Korean Math. Soc. \\textbf{58} (2021),\n643-702], this paper studies the kernel of the Kameko $(\\widetilde\n{Sq^0_*})_{(s; N_d)}$ for the case where $s = 5$ and the generic degree $N_d =\n5(2^{d} - 1) + 11.2^{d+1}.$ We then rectify almost all of the main results that\nwere incorrect in Nguyen Khac Tin's paper [Rev. Real Acad. Cienc. Exactas Fis.\nNat. Ser. A-Mat. \\textbf{116}:81 (2022)]. We have also constructed several\nadvanced algorithms in SAGEMATH to validate our results. These new algorithms\nmake an important contribution to tackling the intricate task of explicitly\ndetermining both the dimension and the basis for the indecomposables $\\mathbb\nF_2 \\otimes_{\\mathscr A} \\mathcal {P}_s$ at positive degrees, a problem\nconcerning algorithmic approaches that had not previously been addressed by any\nauthor. Furthermore, this paper encompasses an investigation of the fifth\ncohomological transfer's behavior in the aforementioned degrees $N_d.$","PeriodicalId":501119,"journal":{"name":"arXiv - MATH - Algebraic Topology","volume":"43 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"On the mod-2 cohomology of the product of the infinite lens space and the space of invariants in a generic degree\",\"authors\":\"Dang Vo Phuc\",\"doi\":\"arxiv-2408.07485\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Let $\\\\mathbb S^{\\\\infty}/\\\\mathbb Z_2$ be the infinite lens space. Denote the\\nSteenrod algebra over the prime field $\\\\mathbb F_2$ by $\\\\mathscr A.$ It is\\nwell-known that the cohomology $H^{*}((\\\\mathbb S^{\\\\infty}/\\\\mathbb Z_2)^{\\\\oplus\\ns}; \\\\mathbb F_2)$ is the polynomial algebra $\\\\mathcal {P}_s:= \\\\mathbb F_2[x_1,\\n\\\\ldots, x_s],\\\\, \\\\deg(x_i) = 1,\\\\, i = 1,\\\\, 2,\\\\ldots, s.$ The Kameko squaring\\noperation $(\\\\widetilde {Sq^0_*})_{(s; N)}: (\\\\mathbb F_2\\\\otimes_{\\\\mathscr A}\\n\\\\mathcal {P}_s)_{2N+s} \\\\longrightarrow (\\\\mathbb F_2\\\\otimes_{\\\\mathscr A}\\n\\\\mathcal {P}_s)_{N}$ is indeed a valuable homomorphism for studying the\\ndimension of the indecomposables $\\\\mathbb F_2\\\\otimes_{\\\\mathscr A} \\\\mathcal\\n{P}_s,$ It has been demonstrated that this $(\\\\widetilde {Sq^0_*})_{(s; N)}$ is\\nonto. Motivated by our previous work [J. Korean Math. Soc. \\\\textbf{58} (2021),\\n643-702], this paper studies the kernel of the Kameko $(\\\\widetilde\\n{Sq^0_*})_{(s; N_d)}$ for the case where $s = 5$ and the generic degree $N_d =\\n5(2^{d} - 1) + 11.2^{d+1}.$ We then rectify almost all of the main results that\\nwere incorrect in Nguyen Khac Tin's paper [Rev. Real Acad. Cienc. Exactas Fis.\\nNat. Ser. A-Mat. \\\\textbf{116}:81 (2022)]. We have also constructed several\\nadvanced algorithms in SAGEMATH to validate our results. These new algorithms\\nmake an important contribution to tackling the intricate task of explicitly\\ndetermining both the dimension and the basis for the indecomposables $\\\\mathbb\\nF_2 \\\\otimes_{\\\\mathscr A} \\\\mathcal {P}_s$ at positive degrees, a problem\\nconcerning algorithmic approaches that had not previously been addressed by any\\nauthor. Furthermore, this paper encompasses an investigation of the fifth\\ncohomological transfer's behavior in the aforementioned degrees $N_d.$\",\"PeriodicalId\":501119,\"journal\":{\"name\":\"arXiv - MATH - Algebraic Topology\",\"volume\":\"43 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-08-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - MATH - Algebraic Topology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2408.07485\",\"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 - Algebraic Topology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2408.07485","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
On the mod-2 cohomology of the product of the infinite lens space and the space of invariants in a generic degree
Let $\mathbb S^{\infty}/\mathbb Z_2$ be the infinite lens space. Denote the
Steenrod algebra over the prime field $\mathbb F_2$ by $\mathscr A.$ It is
well-known that the cohomology $H^{*}((\mathbb S^{\infty}/\mathbb Z_2)^{\oplus
s}; \mathbb F_2)$ is the polynomial algebra $\mathcal {P}_s:= \mathbb F_2[x_1,
\ldots, x_s],\, \deg(x_i) = 1,\, i = 1,\, 2,\ldots, s.$ The Kameko squaring
operation $(\widetilde {Sq^0_*})_{(s; N)}: (\mathbb F_2\otimes_{\mathscr A}
\mathcal {P}_s)_{2N+s} \longrightarrow (\mathbb F_2\otimes_{\mathscr A}
\mathcal {P}_s)_{N}$ is indeed a valuable homomorphism for studying the
dimension of the indecomposables $\mathbb F_2\otimes_{\mathscr A} \mathcal
{P}_s,$ It has been demonstrated that this $(\widetilde {Sq^0_*})_{(s; N)}$ is
onto. Motivated by our previous work [J. Korean Math. Soc. \textbf{58} (2021),
643-702], this paper studies the kernel of the Kameko $(\widetilde
{Sq^0_*})_{(s; N_d)}$ for the case where $s = 5$ and the generic degree $N_d =
5(2^{d} - 1) + 11.2^{d+1}.$ We then rectify almost all of the main results that
were incorrect in Nguyen Khac Tin's paper [Rev. Real Acad. Cienc. Exactas Fis.
Nat. Ser. A-Mat. \textbf{116}:81 (2022)]. We have also constructed several
advanced algorithms in SAGEMATH to validate our results. These new algorithms
make an important contribution to tackling the intricate task of explicitly
determining both the dimension and the basis for the indecomposables $\mathbb
F_2 \otimes_{\mathscr A} \mathcal {P}_s$ at positive degrees, a problem
concerning algorithmic approaches that had not previously been addressed by any
author. Furthermore, this paper encompasses an investigation of the fifth
cohomological transfer's behavior in the aforementioned degrees $N_d.$