  We study meromorphic jacobian pairs, i.e., pairs of polynomials in one
variable, with coefficients meromorphic series in a second variable, whose
jacobian relative to the two variables depends only on the second variable. We
pose two meromorphic jacobian conjectures about such pairs, one of which is in
terms of an invariant of the pair which we call the beta invariant. These
conjectures are shown to imply the bivariate algebraic jacobian conjecture
which predicts that two bivariate polynomials generate the polynomial ring if
their jacobian is a nonzero constant. As another technique for studying the
jacobian conjecture we revisit the Newton polygon.
