**Question:** Is is possible to realise the positive root lattice $\Phi_{\Delta}^{>0}$ (viewed as an abstract poset) of a root system $\Phi_\Delta$ associated to a Dynkin or affine Dynkin diagram $\Delta$ in terms of the set of reflections of the corresponding Weyl group $W_\Delta$ together with a choice of coxeter element ? In other words is it possible to define
a partial order $\leq_{\, c}$ on the set of all reflections in $W_\Delta$ ---- depending only upon on a choice of coxeter element $c$ --- which is isomorphic to $\Phi_\Delta^{>0}$ as a poset.

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