.. _migration:

Migration
=========
The fundamental contrast between singlezone and multizone models of chemical
evolution is the variation of parameters between zones. However, these models
often involve some sort of prescription for how stars mix between zones in
order to mimic the changes in a stars' locations over time. In nature, the
details of this component of evolution likely varies on a galaxy-by-galaxy
basis. In keeping with VICE's philosophy of making as few assumptions as
possible to maximize the user's power over their simulations, VICE is
implemented with an agnostic approach to the migration prescription in a
multizone model.

In multizone models, VICE knows nothing of the spatial configuration of the
zones the user is operating under. The only piece of information identifying
a zone is an integer index (a *zero-based* integer index, specifically). These
zones can be coupled via migration by moving gas and stars from one zone to
any other zone under a user-constructed prescription. In principle, this
allows the construction of 1-, 2-, and 3-dimensional zone configurations with
an arbitrary migration prescription.

.. _migration_stars:
.. include:: stars.rst

.. _migration_gas:
.. include:: gas.rst