Kern NMR air alpha particle antibaryon antilepton antimeson atom atomic nucleus atomic particle atomic particles baryon beta particle brute matter building block chemical element component constituent earth electron element elementary unit fire fundamental particle hyle hypostasis lepton material material world materiality matter meson molecule monad natural world nature neutron nuclear force nuclear magnetic resonance nuclear particle nuclear resonance nucleon nucleosynthesis nucleus photon physical world plenum proton strangeness strong interaction stuff substance substratum the four elements triton unit of being valence electron water