Speaker
Description
Dynamical symmetry breaking plays a crucial role in mass and scale
generation. In QCD-like theories, its dependence on the number of
fermion flavours determines the phase structure and the transition to
the conformal regime. In this work, we employ the functional
renormalisation group and the generalised flow equation to compute
non-perturbative corrections, including momentum dependencies and field
invariants essential for an adequate realisation of the global symmetry.
As a consequence, the critical gauge coupling required for dynamical
chiral symmetry breaking acquires a strong dependence on the number of
flavours and increases sharply at $N_f^\textrm{crit}\simeq7.30$ at
$N_c=3$. This establishes a new picture of the conformal phase
transition that challenges Miransky/BKT scaling and the existence of
walking regimes, favours a first-order quantum phase transition, and
points towards a critical region with exotic dynamics and symmetric
fermion mass gaps.