This grant supports the research of Dr. D. Chudnovsky and Dr. G. Chudnovsky as principal investigators. They intend to study approximations to functions and numbers with a view to revealing arithmetic properties of classical constants. They intend to use Pade approximations in conjunction with isomonodromy deformation equations. This is research in the field of number theory. Number theory starts with the whole numbers and questions such as the divisibility of one whole number by another. It is among the oldest fields of mathematics and it was originally pursued for purely aesthetic reasons. However, within the last half century, it has become an essential tool in developing new algorithms for computer science and new error correcting codes for electronics.