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We study the homotopy groups of the configuration space of discs inside aunit disc just beyond the first critical radius. We find a non-trivial `thickbraid' (loop in the configuration space), which is trivial in the orderedconfiguration space of points when replacing each disc by its centre, in thecase $n=4$. We find a non-contractible $(n-3)$-sphere for $n\ge 5$, where $r$is between the first two critical radii, and explore the persistence of thishomotopy class when the ambient unit disc is deformed. For sufficiently large$n$, we demonstrate the existence of non-trivial $\pi_k$-classes with $k<n-3$beyond higher critical radii.

Thick braids and other non-trivial homotopy in configuration spaces of hard discs