Model Completion
Model completion is a term employed when Existential Closure is successful. The formation of theComplex Numbers, and the move from affine to projective geometry, are successes of this kind. The theory of existential closure gives a theoretical basis of Hilbert's 
``method of ideal elements.''
References
Manders, K. L. ``Interpretations and the Model Theory of the Classical Geometries.'' In Models and Sets. Berlin: Springer-Verlag, pp. 297-330, 1984. Manders, K. L. ``Domain Extension and the Philosophy of Mathematics.'' J. Philos. 86, 553-562, 1989.
- Julia Set
- Jump
- Jump Angle
- Jumping Champion
- Jung's Theorem
- Just If
- Just One
- Kabon Triangles
- Kac Formula
- Kac Matrix
- Kakeya Needle Problem
- Kakutani's Fixed Point Theorem
- Kakutani's Problem
- Kalman Filter
- Kampyle of Eudoxus
- KAM Theorem
- Kanizsa Triangle
- Kantorovich Inequality
- Kaplan-Yorke Conjecture
- Kaplan-Yorke Dimension
- Kaplan-Yorke Map
- Kappa Curve
- Kaprekar Number
- Kaprekar Routine
- Kaps-Rentrop Methods