Complex sentence: His continuum hypothesis is the proposition that\\ mathfrak is the same as\\ aleph_1, but this has been found to be independent of the standard axioms of mathematical set theory; it can neither be proved nor disproved under the standard assumptions.
Split into simpler sentences: His continuum hypothesis is the proposition that\\ mathfrak is the same as\\ aleph_1. This hypothesis has been found to be independent of the standard axioms of mathematical set theory; it can neither be proved nor disproved under the standard assumptions.