Geometry & Topology

The Extended Bloch Group and the Cheeger–Chern–Simons Class

Sebastian Goette and Christian Zickert

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We present a formula for the full Cheeger–Chern–Simons class of the tautological flat complex vector bundle of rank 2 over BSL(2,δ). This improves the formula by Dupont and Zickert [Geom. Topol. 10 (2006) 1347–1372], where the class is only computed modulo 2–torsion.

Article information

Geom. Topol., Volume 11, Number 3 (2007), 1623-1635.

Received: 5 June 2007
Revised: 11 July 2007
Accepted: 4 July 2007
First available in Project Euclid: 20 December 2017

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 57R20: Characteristic classes and numbers 11G55: Polylogarithms and relations with $K$-theory

Extended Bloch group Cheeger-Chern-Simons class Rogers dilogarithm


Goette, Sebastian; Zickert, Christian. The Extended Bloch Group and the Cheeger–Chern–Simons Class. Geom. Topol. 11 (2007), no. 3, 1623--1635. doi:10.2140/gt.2007.11.1623.

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