Abstract:
Let $P$ be a principal
$\mathrm{GL}_n$-bundle over a smooth compact manifold $X$
given by a finite atlas $\mathscr U=\{U_\alpha\}$ with transition functions
$g_{\alpha\beta}$. A method is described for constructing the cocycles
corresponding to the Chern classes of the bundle $P$ in the
Čech complex with coefficients in the sheaf of de Rham forms on
the manifold associated with the atlas $\mathscr U$. It is proved
that for every rational characteristic class $c$ of the
bundle $P$ there exists a cocycle in the aforementioned complex depending only on the
gluing functions and corresponding to the class $c$ under the
canonical identification of the cohomologies
of the complex and the de Rham cohomologies of the manifold $X$
(a simple algorithm is given that enables one to calculate this cocycle explicitly).
One of the key ideas leading to these results is the idea of
using the notion of a twisting cochain for constructing the cocycles.
Bibliography: 14 titles.