Degeneration of the modified diagonal cycle

Jaya N. Iyer; Stefan Müller-Stach

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arXiv · 1401.2796

Degeneration of the modified diagonal cycle

Jaya N. Iyer·Stefan Müller-Stach

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Abstract

In this note, we revisit the modified diagonal cycle of Gross and Schoen. We look at degenerations of this cycle, induced by a degeneration of the curve C, and explain how the specialization map with respect to the central fiber produces a higher Chow cycle. When C is non-hyperelliptic of genus three, and degenerates to a nodal curve, the degeneration of the cycle corresponds to an indecomposable higher Chow cycle on a curve of genus two.

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Jaya N. Iyer, Stefan Müller-Stach. 2014-01-13. Degeneration of the modified diagonal cycle. https://arxiv.org/abs/1401.2796

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