FTP, name this hypothesis posited by Georg Cantor in which there is no infinite set with a cardinal number between that of the set of integers and the set of real numbers.
The first of Hilbert's problems, Kurt Gödel proved that it was not contradictory to add it to Zermelo-Fraenkel set theory, but twenty-three years later Paul Cohen showed that its negation could be added to set theory without a contradiction as well, therefore rendering it undecidable. FTP, name this hypothesis posited by Georg Cantor in which there is no infinite set with a cardinal number between that of the set of integers and the set of real numbers.
The first of Hilbert's problems, Kurt Gödel proved that it was not contradictory to add it to Zermelo-Fraenkel set theory, but twenty-three years later Paul Cohen showed that its negation could be added to set theory without a contradiction as well, therefore rendering it undecidable.
{Continuum} Hypothesis