Estimate of number of simplices of triangulations of Lie groups

Abstract

We present estimates of number of simplices of given dimension of classical compact Lie groups. As in the previous work \cite{GMP2} the approach is a combination of an estimate of number of vertices with a use of valuation of the covering type by cohomological argument of \cite{GMP} and application of the recent versions of the Lower Bound Theorem of combinatorial topology. For the case of exceptional Lie groups we made a complete calculation using the description of their cohomology rings given by the first and third author. For infinite increasing series of Lie groups of growing dimension $d$ the rate of growth of number of simplices of highest dimension is given which extends onto the case of simplices of (fixed) codimension $d-i$.