The stupendous power of the Tevatron made possible the 1995 discovery of the top quark - the last of six flavors of quarks predicted by the standard model theory of particle physics.
Particle physics is a field that is difficult to understand 
( z1 field :mod ( z2 difficult :domain ( z3 understand :ARG1 ( z4 physics :mod ( z5 particle ) ) ) ) )