A model is described that can be used to estimate the bulk polarization of large rotating meteoroids in the magnetic field of a neutron star. The results of this model are applicable to the Supernova Neutrino Amino Acid Processing model, which describes one possible way in which the amino acids, known in nearly all cases to exhibit supramolecular chirality, could have become enantiomeric. Keywords: amino acids; chirality; neutrinos; weak interaction It is generally accepted that if some

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... m can introduce an imbalance in the populations of the left-and right-handed forms of any amino acid [5], successive synthesis or evolution of the molecules involving autocatalytic reactions can amplify this enantiomerism ultimately to produce a single form. What is not well understood, however, is the mechanism by which the initial imbalance is produced, and the means by which it always produces the left-handed chirality observed in the amino acids. This enigma has been discussed in numerous reviews in past years (see, e.g., [8] [9] [10] [11] [12] [13] [14] ). The energy states of the left-and right-handed forms have been shown, by detailed computations, to differ at most by infinitesimal amounts due to parity violation [15, 16] , so it would be difficult for thermal equilibrium to produce the imbalance. However, some evidence exists that electroweak parity-violating energy shifts could produce an enantiomeric excess if the molecules are in a gas-phase [17] . Recent work [18, 19] has suggested that the chirality of the amino acids could be established in the magnetic field of a nascent neutron star from a core-collapse supernova via processing by the neutrinos that would be emitted. This model, the Supernova Neutrino Amino Acid Processing model, or SNAAP model, not only appears to produce a small chiral imbalance, but always produces the same sign of the chirality. Another suggested mechanism lies with the processing of a population of amino acids by circularly polarized light [20] [21] [22] [23] [24] [25] ; this could select one chirality over the other. However, this solution does not easily explain why the physical conditions that would select one form in one place would not select the other in a different location. Nonetheless [22] , a region as small as a planetary system could be processed by the output from a localized region of a single star so that all of the light could be of a single circular polarization, and this could explain the observed meteoritic and Earth's results. Another problem with this model is that it must destroy large amounts of amino acids in order to produce significant enantiomerism [22] . Another possibility [26] invokes selective processing by some manifestation of the weak interaction, which does violate parity conservation, so it might perform a chiral selection. This idea was based on earlier work [27, 28] . Mann et al. [26] focused on the β-decay of 14 C to produce the selective processing. However, it was not possible in that study to show how simple β-decay could produce chiral-selective molecular destruction. A modern update on this possibility [29] does appear to produce some enantiomerism. Another suggestion [30] assumed that neutrinos emitted by a core-collapse supernova would selectively process the carbon or the hydrogen in the amino acids to produce enantiomerism. This suggestion also did not explain how a predisposition toward one or the other molecular chirality could evolve from the neutrino interactions. A similar suggestion [31] involves the effects of neutrinos from supernovae on molecular electrons. It was also suggested that the differences between ortho-and para-hydrogen pairs [32] in the amino acids could produce a chiral selection. The possibility that dark matter or cosmological neutrinos could select enantiomers has also been studied [33] .