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Let $T$ be the theory of dense cyclically ordered sets with at least two elements. We determine the classifying space of $\mathsf{Mod}(T)$ to be homotopically equivalent to $\mathbb{CP}^\infty$. In particular, $\pi_2(\lvert\mathsf{Mod}(T)\rvert)=\mathbb{Z}$, which answers a question in our previous work. The computation is based on Connes' cycle category $\Lambda$., Comment: 6 pages

We prove that for any homotopy type $X$, there is an abstract elementary class $\mathcal{C}$, with joint embedding, almagamation and no maximal models such that the classifying space realizes the homotopy type $X$. We provide a few explicit examples., Comment: 11 pages. To appear in the Journal of Pure and Applied Algebra

We show that the Lascar group $\operatorname{Gal}_L(T)$ of a first order theory $T$ is naturally isomorphic to the fundamental group $\pi_1(|\operatorname{Mod}(T)|)$ of the classifying space of the category of models of $T$ and elementary embeddings., Comment: 21 pages