Confirmation of the theory of 'superstrings' as the fundamental constituents of matter, for example, remains, in spite of enormous efforts, almost impossible to imagine.

At this point, called absolute zero, the particle constituents of matter have minimal motion and can become no colder.

Both quarks and leptons are elementary particles, and are currently seen as being the fundamental constituents of matter.

Because electrons are the fundamental constituents of matter involved in bonding, their involvement in bonding has been studied exhaustively by chemists.

Roughly speaking, bosons are the constituents of radiation, while fermions are the constituents of matter.