Trudy Instituta Matematiki i Mekhaniki UrO RAN
RUS  ENG    JOURNALS   PEOPLE   ORGANISATIONS   CONFERENCES   SEMINARS   VIDEO LIBRARY   PACKAGE AMSBIB  
General information
Latest issue
Archive
Impact factor

Search papers
Search references

RSS
Latest issue
Current issues
Archive issues
What is RSS



Trudy Inst. Mat. i Mekh. UrO RAN:
Year:
Volume:
Issue:
Page:
Find






Personal entry:
Login:
Password:
Save password
Enter
Forgotten password?
Register


Trudy Instituta Matematiki i Mekhaniki UrO RAN, 2021, Volume 27, Number 1, Pages 103–109
DOI: https://doi.org/10.21538/0134-4889-2021-27-1-103-109
(Mi timm1795)
 

On а question concerning the tensor product of modules

A. V. Konygin

Institute of Mathematics and Mechanics, Ural Branch of the Russian Academy of Sciences, Ekaterinburg
References:
Abstract: Assume that $G$ is a group, $K$ is an algebraically closed field, and $V_1$ and $V_2$ are $KG$-modules. The following question is considered: under what constraints on $G$, $K$, $V_1$, and $V_2$ does $V_1 \otimes V_2 \cong V_1 \otimes I$ hold, where $I$ is the trivial $KG$-module (of dimension $\dim(V_2)$)? Earlier, when considering a problem of P. Cameron on finite primitive permutation groups, the author obtained and used some results on this question. This work continues the study of the question. The following results were obtained. 1. Assume that $G$ is a nontrivial connected reductive algebraic group, and $V_1$ and $V_2$ are faithful semisimple $KG$-modules. Then $V_1 \otimes V_2 \ncong V_1 \otimes I$. 2. Assume that $G$ is a nontrivial finite group, $\mathrm{char} (K) = 0$, $V_1$ is a $KG$-module, and $V_2$ is a faithful $KG$-module. Then $V_1 \otimes V_2 \cong V_1 \otimes I $ if and only if $V_1$ is the direct sum of $\frac {\dim (V_1)} {|G|}$ regular $KG$-modules. In addition, we consider the question of the possibility that $V_1 \otimes V_2 \cong V_1 \otimes I$ in the case where $G = SL_2(p^n)$, $V_1$ and $V_2$ are simple $KG$-modules, and $\mathrm{char}(K) = p$.
Keywords: finite group, algebraic group, group representation, tensor product of modules.
Funding agency Grant number
Russian Foundation for Basic Research 20-01-00456
This work was supported by the Russian Foundation for Basic Research (project no. 20-01-00456).
Received: 22.11.2020
Revised: 30.12.2020
Accepted: 11.01.2021
Bibliographic databases:
Document Type: Article
UDC: 512.542, 512.547
Language: Russian
Citation: A. V. Konygin, “On а question concerning the tensor product of modules”, Trudy Inst. Mat. i Mekh. UrO RAN, 27, no. 1, 2021, 103–109
Citation in format AMSBIB
\Bibitem{Kon21}
\by A.~V.~Konygin
\paper On а question concerning the tensor product of modules
\serial Trudy Inst. Mat. i Mekh. UrO RAN
\yr 2021
\vol 27
\issue 1
\pages 103--109
\mathnet{http://mi.mathnet.ru/timm1795}
\crossref{https://doi.org/10.21538/0134-4889-2021-27-1-103-109}
\elib{https://elibrary.ru/item.asp?id=4482398}
Linking options:
  • https://www.mathnet.ru/eng/timm1795
  • https://www.mathnet.ru/eng/timm/v27/i1/p103
  • Citing articles in Google Scholar: Russian citations, English citations
    Related articles in Google Scholar: Russian articles, English articles
    Trudy Instituta Matematiki i Mekhaniki UrO RAN
     
      Contact us:
     Terms of Use  Registration to the website  Logotypes © Steklov Mathematical Institute RAS, 2025