Event:
A study describing the Big Bang, published in 'Physical Review', suggests it is actually a phase change ruled by event symmetry, a theory which best supports how spacetime could originate from original matter
More Notable Events on August 21:
1993 NASA loses contact with Mars Observer
1989 Voyager 2 begins a flyby of planet Neptune
1968 Democratic Convention opens in Chicago
1968 Warsaw Pact forces enter Czechoslovakia to end reform movement
1897 Oldsmobile begins operation as a General Motors Corp division