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Half twists of Hodge structures of CM-type

Bert van Geemen
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Abstract

To a Hodge structure V of weight k with CM by a field K we associate Hodge structures V_{-n/2} of weight k+n for n positive and, under certain circumstances, also for n negative. We show that these `half twists' come up naturally in the Kuga-Satake varieties of weight two Hodge structures with CM by an imaginary quadratic field.

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Bert van Geemen. 2000-08-10. Half twists of Hodge structures of CM-type. https://arxiv.org/abs/math/0008076

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