 where we believe, according to string theory, that just as we can divide up a chunk of rock into smaller chunks, eventually into molecules, divide those molecules into atoms, divide those atoms into protons and neutrons, divide those protons and neutrons into quarks, we believe, according to string theory, that the quarks themselves, which were formerly thought to be indivisible, could actually be fractionalized and broken into even tinier things called strings or sometimes superstrings.