Séminaire par Josep M. RIBO
Mercredi 15 Mai 2019 - 11h - Salle Maroni / MHT
Josep M. RIBO, Professeur Emérite à l'Université de Barcelone, fera une présentation intitulée: "Enantioselective Autocatalytic Reactions Leading to Racemic Biases: Scenarios for the Emergence of Homochirality in Chemical Evolution"
The physico-chemical basis to yield racemic biases in autocatalytic networks as dissipative open systems are discussed. Spontaneous mirror symmetry breaking (SMSB) occurs because dissipative reaction networks may yield a metastable racemic non-equilibrium stationary state (NESS) that transforms in one of two stable enantiomeric NESSs. In such a scenario the type of the reaction network as well the boundary conditions are similar to the current accepted stages of emergence of replicators and autocatalytic systems: resilience to racemization would emerge at the same stages leading to functional polymers able to transfer information transfer. Simple asymmetric inductions by natural chiral forces at previous stages of chemical evolution, for example in astrophysical scenarios, are necessary to drive the SMSB stochastic distribution of chiral signs in a deterministic one.
