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INDECOMPOSABLE REPRESENTATIONS OF THE EUCLIDEAN ALGEBRA 𝔢(3) FROM IRREDUCIBLE REPRESENTATIONS OF

Published online by Cambridge University Press:  01 April 2011

ANDREW DOUGLAS*
Affiliation:
Department of Mathematics, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201, USA (email: [email protected])
JOE REPKA
Affiliation:
Department of Mathematics, University of Toronto, 40 St. George Street, Toronto, ON, Canada M5S 2E4 (email: [email protected])
*
For correspondence; e-mail: [email protected]
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Abstract

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The Euclidean group E(3) is the noncompact, semidirect product group E(3)≅ℝ3⋊SO(3). It is the Lie group of orientation-preserving isometries of three-dimensional Euclidean space. The Euclidean algebra 𝔢(3) is the complexification of the Lie algebra of E(3). We embed the Euclidean algebra 𝔢(3) into the simple Lie algebra and show that the irreducible representations V (m,0,0) and V (0,0,m) of are 𝔢(3)-indecomposable, thus creating a new class of indecomposable 𝔢(3) -modules. We then show that V (0,m,0) may decompose.

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2011

Footnotes

The work of A.D. is partially supported by the Professional Staff Congress/City University of New York (PSC/CUNY). The work of J.R. is partially supported by the Natural Sciences and Engineering Research Council (NSERC).

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