Not ad infinitum
In Mathematical, in the under-field of the projective Geometry, the not ad infinitum is a not which can be added to a body.
Real numbers
When the point ad infinitum is added to the right-hand side of the real numbers, this one forms a Courbe closed, called the projective Droite real, .
Let us consider two lines now parallel S in the projective Plan . Since the two lines are parallel, they ad infinitum cross in a not . This one is on the Droite ad infinitum in .
Moreover, each line is, in , a projective Droite: each one with its clean not ad infinitum . Two lines of a Espace refines are parallel if and only if they have same the not ad infinitum .
Complex numbers
The point ad infinitum can also be added to the complex plan in order to obtain the projective line complexes, i.e. the Sphère of Riemann. One can conceive this by imagining the opposite process initially: that is to say a Sphere which one perforates. The resulting hole forms a edge which one stretches towards the infinite one. This forms the complex plan. By reversing this process, one transforms the complex plan into projective right-hand side complexes : the hole is " déperforé" by ajouant the not ad infinitum , which is equivalent to each point on the edge which formed the edges of the hole.
See too
- Right ad infinitum
- Hyperplane of infinite the (plane of infinite)