  In analogy with the Riemann zeta function at positive integers, for each
finite field F_p^r with fixed characteristic p we consider Carlitz zeta values
zeta_r(n) at positive integers n. Our theorem asserts that among the zeta
values in {zeta_r(1), zeta_r(2), zeta_r(3), ... | r = 1, 2, 3, ...}, all the
algebraic relations are those algebraic relations within each individual family
{zeta_r(1), zeta_r(2), zeta_r(3), ...}. These are the algebraic relations
coming from the Euler-Carlitz relations and the Frobenius relations. To prove
this, a motivic method for extracting algebraic independence results from
systems of Frobenius difference equations is developed.
