| − | The theory that light is sometimes a particle and sometimes a wave.<ref>Wile, Dr. Jay L. ''Exploring Creation With Chemistry''. Apologia Educational Ministries, Inc. 1998</ref> | + | The theory that light can behave as both a particle and a wave depending on the manner in which it is observed.<ref>Wile, Dr. Jay L. ''Exploring Creation With Chemistry''. Apologia Educational Ministries, Inc. 1998</ref> |