On the zero-divisor-cup-length of spaces of oriented isometry classes of planar polygons

Using information about the rational cohomology ring of the space M(ℓ1,…,ℓn)M(ℓ1,…,ℓn) of oriented isometry classes of planar n-gons with the specified side lengths, we obtain bounds for the zero-divisor-cup-length (zcl) of these spaces, which provide lower bounds for their topological complexity (TC). In many cases our result about the cohomology ring is complete and we determine the precise zcl. We find that there will usually be a significant gap between the bounds for TC implied by zcl and dimensional considerations.