"The hole is the vacuous force which acts as an expansion pressure force exerted against an equal compression pressure force which is located in mass and culminates at its centres." [Russell to NYT - 1930 November 2]
See Also
4plusplus
Affinity
Assimilation
Bjerknes Effect
bondage of compression
centrifugal force
Compression
Electric compression
electric force
Father
Gravitation
Love
speed of compression
Syntropy
two-way compression-expansion sequence