Let
be an amenable
group and let
be an irreducible complete algebraic variety over an algebraically closed field
. Let
denote the
set of
-points
of
and let
be an algebraic cellular
automaton over
,
that is, a cellular automaton over the group
and the
alphabet
whose local defining map is induced by a morphism of
-algebraic
varieties. We introduce a weak notion of preinjectivity for algebraic cellular automata, namely
-preinjectivity, and prove
that
is surjective if and
only if it is
-preinjective.
In particular,
has the Myhill property, i.e., is surjective whenever it is preinjective. Our result gives
a positive answer to a question raised by Gromov (J. Eur. Math. Soc.1:2 (1999),
109–197) and yields an analogue of the classical Moore–Myhill Garden of Eden
theorem.
Keywords
algebraic cellular automaton, complete algebraic variety,
projective algebraic variety, amenable group, Krull
dimension, algebraic mean dimension, preinjectivity, Garden
of Eden theorem