International Journal of Mathematics and Mathematical Sciences
Volume 27 (2001), Issue 4, Pages 201-214
doi:10.1155/S0161171201006767
Abstract
We introduce a special type of reduction in the ring of differential polynomials and develop the appropriate technique of characteristic sets that allows to generalize the classical Kolchin's theorem on differential dimension polynomial and find new differential birational invariants of a finitely generated differential field extension.