Back-and-forth systems for generic curves and a decision algorithm for the limit theory Original Research Article

It was recently shown that the theories of generic algebraic curves converge to a limit theory as their degrees go to infinity. In this paper we give quantitative versions of this result and other similar results. In particular, we show that generic curves of degree higher than 22r cannot be distinguished by a first-order formula of quantifier rank r. A decision algorithm for the limit theory then follows easily. We also show that in this theory all formulas are equivalent to boolean combinations of existential formulas, and give a quantitative version of this result.