  We investigate chiral symmetry breaking in the (2+1)-dimensional Thirring
model as a function of the coupling as well as the Dirac flavor number Nf with
the aid of the functional renormalization group. For small enough flavor number
Nf < Nfc, the model exhibits a chiral quantum phase transition for sufficiently
large coupling. We compute the critical exponents of this second order
transition as well as the fermionic and bosonic mass spectrum inside the broken
phase within a next-to-leading order derivative expansion. We also determine
the quantum critical behavior of the many-flavor transition which arises due to
a competition between vector and chiral-scalar channel and which is of second
order as well. Due to the problem of competing channels, our results rely
crucially on the RG technique of dynamical bosonization. For the critical
flavor number, we find Nfc ~ 5.1 with an estimated systematic error of
approximately one flavor.
