Molecular dynamics (MD) simulations have been performed on poly(ethylene oxide) (PEO) and its oligomers, using quantum chemistry-based force fields with and without many-body polarizable interactions. Inclusion of the many-body polarization in the model resulted in increased populations of the tgt and tgg conformations of 1,2-dimethoxyethane and slightly slower dynamics. Increasing the PEO dipole moment also led to increased populations of the tgt and ttg conformers and slower dynamics. Quasi-elastic neutron scattering, dielectric relaxation, and C-13 spin-lattice relaxation experiments have been performed on PEO and its oligomers. New C-13 NMR experiments yielded spin-lattice relaxation times that were similar to2-3 times larger than those in the previous experiments, which is in good agreement with the current simulation results. Good agreement between the MD simulation results using many-body polarizable and two-body nonpolarizable potentials was found with experiments for thermodynamic, transport, structural, and dynamic properties.