Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles
Let λbe a finite-dimensional representation of a connected nilpotent group Gand Ube a unitary representation of G. We investigate the structure of the extensions of λby Uand, correspondingly, the group H1(λ, U)of 1-cohomologies. A spectral criterion of triviality of H1(λ, U)is proved and systematica...
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Elsevier
2015
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Online Access: | https://repository.londonmet.ac.uk/1013/7/SECOND%20SUBMISSION%20TO%20JFA-15-137R1.pdf |
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author | Kissin, Edward Shulman, Victor S. |
author_facet | Kissin, Edward Shulman, Victor S. |
author_sort | Kissin, Edward |
collection | LMU |
description | Let λbe a finite-dimensional representation of a connected nilpotent group Gand Ube a unitary representation of G. We investigate the structure of the extensions of λby Uand, correspondingly, the group H1(λ, U)of 1-cohomologies. A spectral criterion of triviality of H1(λ, U)is proved and systematically used in the study of various types of decomposition of the extensions. We consider a special type of (λ, U)-cocycles – neutral cocycles, which play a crucial role in the theory of J-unitary representations of groups on Pontryagin Πk-spaces. |
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format | Article |
id | oai:repository.londonmet.ac.uk:1013 |
institution | London Metropolitan University |
language | English |
last_indexed | 2024-07-09T03:46:05Z |
publishDate | 2015 |
publisher | Elsevier |
record_format | eprints |
spelling | oai:repository.londonmet.ac.uk:10132020-05-29T16:27:50Z http://repository.londonmet.ac.uk/1013/ Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles Kissin, Edward Shulman, Victor S. 510 Mathematics Let λbe a finite-dimensional representation of a connected nilpotent group Gand Ube a unitary representation of G. We investigate the structure of the extensions of λby Uand, correspondingly, the group H1(λ, U)of 1-cohomologies. A spectral criterion of triviality of H1(λ, U)is proved and systematically used in the study of various types of decomposition of the extensions. We consider a special type of (λ, U)-cocycles – neutral cocycles, which play a crucial role in the theory of J-unitary representations of groups on Pontryagin Πk-spaces. Elsevier 2015-07-22 Article PeerReviewed text en https://repository.londonmet.ac.uk/1013/7/SECOND%20SUBMISSION%20TO%20JFA-15-137R1.pdf Kissin, Edward and Shulman, Victor S. (2015) Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles. Journal of Functional Analysis, 269 (8). pp. 2564-2610. ISSN 0022-1236 http://dx.doi.org/10.1016/j.jfa.2015.07.003 10.1016/j.jfa.2015.07.003 |
spellingShingle | 510 Mathematics Kissin, Edward Shulman, Victor S. Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles |
title | Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles |
title_full | Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles |
title_fullStr | Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles |
title_full_unstemmed | Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles |
title_short | Non-unitary representations of nilpotent groups, I: Cohomologies, extensions and neutral cocycles |
title_sort | non unitary representations of nilpotent groups i cohomologies extensions and neutral cocycles |
topic | 510 Mathematics |
url | https://repository.londonmet.ac.uk/1013/7/SECOND%20SUBMISSION%20TO%20JFA-15-137R1.pdf |
work_keys_str_mv | AT kissinedward nonunitaryrepresentationsofnilpotentgroupsicohomologiesextensionsandneutralcocycles AT shulmanvictors nonunitaryrepresentationsofnilpotentgroupsicohomologiesextensionsandneutralcocycles |