Aleph null
Alef cero
- Date
- 1895 · confidence low
- Place
- Halle, Saxony-Anhalt, Germany
- Credited to
- Georg Cantor
- Field
- Knowledge & symbols
What was discovered
A transfinite cardinal number representing the size of the set of natural numbers, the smallest of the aleph numbers introduced by Georg Cantor in his set theory.
What it led to
- hierarchy of transfinite cardinals (aleph-one, aleph-two...)
- foundation for the continuum hypothesis
- later development of axiomatic set theory