Connected locally compact groups: The Hochschild kernel and faithfulness of locally bounded finite-dimensional representations

Shtern, A.

doi:10.1090/S0077-1554-2012-00190-3

Connected locally compact groups: The Hochschild kernel and faithfulness of locally bounded finite-dimensional representations
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by A. I. Shtern
Translated by: G. G. Gould

Trans. Moscow Math. Soc. 2011, 79-95

DOI: https://doi.org/10.1090/S0077-1554-2012-00190-3

Published electronically: January 12, 2012

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Abstract:

We obtain a number of consequences of the theorem on the automatic continuity of locally bounded finite-dimensional representations of connected Lie groups on the derived subgroup of the group, as well as an analogue of Lie’s theorem for (not necessarily continuous) finite-dimensional representations of connected soluble locally compact groups. In particular, we give a description of connected Lie groups admitting a (not necessarily continuous) faithful locally bounded finite-dimensional representation; as it turns out, such groups are linear. Furthermore, we give a description of the intersection of the kernels of continuous finite-dimensional representations of a given connected locally compact group, obtain a generalization of Hochschild’s theorem on the kernel of the universal representation in terms of locally bounded (not necessarily continuous) finite-dimensional linear representations, and find the intersection of the kernels of such representations for a connected reductive Lie group.

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