Glueballs from bound state equations

Glueballs are bound states in the spectrum of quantum chromodynamics which consist only gluons. They belong to group exotic hadrons widely studied experimentally and theoretically. We summarize how calculate glueballs a functional framework discuss results for pure Yang-Mills theory. Our setup is totally self-contained with scale being external input. enumerate range tests that provide evidence stability results. This illustrates potential equations as continuum first-principles method complementary lattice calculations.