Nature abhors a vacuum - I say that God abhors a vacuum and can't abide a vacuum anywhere under heaven, however small. All you have to do is get empty of self and automatically, you're full of God.
Meister Eckhard

The phrase 'God abhors a vacuum' is usually not referring to a vacuum in the physical sense, but in many others.

It is often said that Germany in the 1930s was a Power vacuum, where there was no controlling party. From this rose the single most powerful political party the earth has ever seen: the Nazis.

When nothing is known about a new field, there is often a flurry of activity as new discoveries are made into the field, the building blocks of that field, which then quietens down.