Many Wikipedia articles are of good quality but are almost never designed for a specific college course. A further abridged "Timeline of quantum mechanics" was reduced by some 50 % and returned to "w:User:Guy_vandegrift/Timeline of quantum mechanics (abridged)." This Timeline of quantum mechanics (abridged) shows some of the key steps in the development of quantum mechanics, quantum field theories and quantum chemistry that occurred before the end of World War II.