| Resumo: |
It is possible to reconsider the origin of biological homochirality in a novel way by formally invoking the standard groupoid approach to stereochemistry in a thermodynamic context that generalizes Landau's spontaneous symmetry breaking arguments. On Earth, limited metabolic free energy may have served as a low temperature analog to 'freeze' the system in the lowest energy state, i.e., the set of simplest homochiral transitive groupoids representing reproductive chemistries. These engaged in a Darwinian competition until a single configuration survived. Subsequent path dependent evolutionary process locked in this initial condition, in spite of increases in available metabolic free energy. Astrobiological outcomes, given higher initial metabolic free energy densities, could well be considerably richer, for example, of mixed chirality. One result would be a complicated distribution of biological chirality across a statistically large sample of extraterrestrial stereochemisty, in marked contrast with published predictions of a racemic average.
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