  We provide a non-equilibrium thermodynamic description of the life-cycle of a
droplet based, chemically feasible, system of protocells. By coupling the
protocells metabolic kinetics with its thermodynamics, we demonstrate how the
system can be driven out of equilibrium to ensure protocell growth and
replication. This coupling allows us to derive the equations of evolution and
to rigorously demonstrate how growth and replication life-cycle can be
understood as a non-equilibrium thermodynamic cycle. The process does not
appeal to genetic information or inheritance, and is based only on
non-equilibrium physics considerations. Our non-equilibrium thermodynamic
description of simple, yet realistic, processes of protocell growth and
replication, represents an advance in our physical understanding of a central
biological phenomenon both in connection to the origin of life and for modern
biology.

Soft Condensed Matter;Biological Physics