The Stardust and the Molecules of Life (Why are the Amino Acids Left-Handed?)

Abstract

A mechanism for creating and selecting amino acid chirality is identified, and subsequent chemical replication and galactic mixing that would populate the galaxy with the predominant species are described. This involves: (1) the spin of the 14N in the amino acids, or in precursor molecules from which amino acids might be formed coupling to the chirality of the molecules; 2) the neutrinos emitted from the supernova, together with magnetic field from the nascent neutron star or black hole from the supernova selectively destroying one 14N orientation, thereby selecting the chirality associated with the other 14N orientation; (3) amplification by chemical evolution, by which the molecules replicate on a relatively short timescale; and (4) galactic mixing on a longer timescale mixing the selected molecules throughout the galaxy.