We consider the pair correlation functions of both the order parameter field
and its square for phase ordering in the O(n) model with nonconserved order
parameter, in spatial dimension 2≤d≤3 and spin dimension 1≤n≤d.
We calculate, in the scaling limit, the exact short-distance singularities of
these correlation functions and compare these predictions to numerical
simulations. Our results suggest that the scaling hypothesis does not hold for
the d=2O(2) model. Figures (23) are available on request - email
[email protected]: 23 pages, Plain LaTeX, M/C.TH.93/2