  We use a model Hamiltonian to study critical phenomena in manganites. This
Hamiltonian includes long-range strain interactions, and a coupling between the
magnetic order parameter and the strain field. We perform a perturbative
renormalization group (RG) analysis and calculate the static critical
exponents, correct to the one-loop level. We compare our RG results with many
experiments on doped manganite critical systems. Our theory is in excellent
agreement with the experimental values for the critical exponents.
