The Unified Field Theory was a scientific belief which existed amongst the races of the galaxy. The primary version of this theory suggested that the universe was ten dimensional in nature which were all stable at the time just before the Big Bang when the universe was a mass of matter energy. The resultant Big Bang was the collapse of that mono bloc. Whilst it could be described as an explosion, dimensionally it was believed to be the point at which the six higher space time dimensions collapsed which left the four which sentient beings knew were capable of being accessible. (TNG novel: Forever Dark)