- space set
- space singularity
- space smashing to a point
- space structure
- space symmetry
- space theory
- space-time
- space-time Brownian motion
- abstract differential operator
- abstract differentiation theory
- abstract dynamical system
- abstract equation
- abstract evolution equation
- abstract field
- abstract finite group
- abstract function
- abstract geometry
- abstract graph
- abstract group
- abstract harmonic analysis
- abstract homotopy theory
- abstract ideal theory
- abstract integral
- abstract integral equation
- abstract integration theory