Extended Bloch group and the Cheeger-Chern-Simons class

A dilogarithmic formula for the Cheeger-Chern-Simons class

We present a simplification of Neumann's formula for the universal Cheeger-Chern-Simons class of the second Chern polynomial. Our approach is completely algebraic, and the final formula can be applied directly on a homology class in the bar complex.

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

We present a formula for the full Cheeger-Chern-Simons class of the tautological flat complex vector bundle of rank two over BSL(2,\C^δ). Our formula improves the formula by Dupont and Zickert, where the class is only computed modulo 2-torsion.

Bott Integrability and Higher Integrability; Higher Cheeger-Simons and Godbillon-Vey Invariants

This paper studies the interaction of $π_1(M)$ for a $C^\infty$ manifold $M$ with Bott's original obstruction to integrability, and with differential geometric invariants such as Godbillon-Vey and Cheeger-Simons invariants of a foliation. We prove that the ring of higher Pontrjagin and higher Chern classes of an integrable subbundle $E$ of the tangent bundle of a manifold vanishes above dimension $2k$ where $k=dim(TM/E)$, and where the higher Pontrjagin and Chern rings are rings generated by $i^*y \cup p_j(TM/E)$ and by $i^*y \cup c_j(TM/E)$ respectively, with $p_j$ the $j$-th Pontrjagin class…

Extended Bloch group and the Chern-Simons class (Incomplete working version)

We define an extended Bloch group and show it is isomorphic to $H_3(PSL(2,C)^δ;Z)$. Using the Rogers dilogarithm function this leads to an exact simplicial formula for the universal Cheeger-Simons class on this homology group. It also leads to an independent proof of the analytic relationship between volume and Chern-Simons invariant of hyperbolic manifolds conjectured in \cite{neumann-zagier} and proved in \cite{yoshida}, as well as an effective formula for the Chern-Simons invariant of a hyperbolic manifold.

陈 - 西蒙斯型3 - 上循环与离散微分同胚群第三同调中的\(\mathbb{Q}/\mathbb{Z}\) - 挠率

Chern--Simons-type $3$-cocycles and $\mathbb{Q}/\mathbb{Z}$-torsion in the third homology of discrete diffeomorphism groups

研究标准3 - 球面相关群的第三整群同调，通过构造陈 - 西蒙斯型3 - 类、采用挠率控制局部积分方法等，证明其包含\((\mathbb{Q}/\mathbb{Z})^2\)，还在多种流形中检测到\(\mathbb{Q}/\mathbb{Z}\)。

Bloch invariants of hyperbolic 3-manifolds

We define an invariant β(M) of a finite volume hyperbolic 3-manifold M in the Bloch group B(C) and show it is determined by the simplex parameters of any degree one ideal triangulation of M. β(M) lies in a subgroup of \B(\C) of finite \Q-rank determined by the invariant trace field of M. Moreover, the Chern-Simons invariant of M is determined modulo rationals by β(M). This leads to a simplicial formula and rationality results for the Chern Simons invariant which appear elsewhere. Generalizations of β(M) are also described, as well as several interesting examples. An appendix describes a scisso…