Geometric Stabilization of Biomolecular Chirality in Open Systems

ABSTRACT The homochirality of life—the exclusive use of L‐amino acids and the universal right‐handedness of ‐helices—stands as one of the most persistent asymmetries in biology. While often attributed to kinetic or energetic biases, the overwhelming statistical dominance of these chiral forms still lacks a fully compelling thermodynamic and geometric explanation. Here, we propose a geometric mechanism for the stabilization and amplification of biomolecular handedness in open, entropy‐producing systems. By introducing a local chirality marker based on the sign of a scalar triple product (equivalently, the sign of a determinant built from atomic coordinate differences and the local helical axis), we show that right‐handed ‐helices can be can be represented as orientation‐preserving sectors of the local configuration space in the local configuration space. Under physically admissible continuous backbone moves, chirality inversion requires crossing a degenerate subset where the marker vanishes, which constitutes a lower dimensional region of effectively zero measure in the feasible configuration manifold. Consequently, parity‐inverting pathways are dynamically suppressed, and once a chiral sign becomes established, it tends to persist and amplify under irreversible evolution consistent with least‐time free‐energy dissipation. Our framework reframes biomolecular homochirality not as the consequence of a primordial energetic asymmetry but as an emergent, statistically stabilized standard arising from the interplay between nonequilibrium thermodynamics and the geometry of configuration space.