The two sciences differ in the role that theory plays within the discipline. Physics can be divided into experimental and theoretical physics. Historically, theoretical physics has correctly predicted phenomena that were out of experimental reach at the time, and could be verified only after experimental techniques caught up.[8] In chemistry, the role of theory historically has been a retrospective one, summarizing experimental data and predicting the outcome of similar experiments.[9] However, with the increasing power of computational methods in chemistry, it has become possible to predict whether a hypothetical compound is stable or not before experimental data is available.