Physical Review D, vol.105, no.8, 2022 (SCI-Expanded)
We present the results of a conformal bootstrap study of the presumed unitary IR fixed point of quantum electrodynamics in three dimensions (QED3) coupled to Nf=4 two-component Dirac fermions. Specifically, we study the four-point correlators of the SU(4) adjoint fermion bilinear r and the monopole of lowest topological charge M1/2. Most notably, the scaling dimensions of the fermion bilinear r and the monopole M1/2 are found to be constrained into a closed island with a combination of spectrum assumptions inspired by the 1/Nf perturbative results as well as a novel interval positivity constraint on the next-lowest-charge monopole M1. Bounds in this island on the SU(4) and topological U(1)t conserved current central charges cJ, cJt, as well as on the stress tensor central charge cT, are comfortably consistent with the perturbative results. Together with the scaling dimensions, this suggests that a part of estimates from the 1/Nf expansion - even at Nf=4 - provide a self-consistent solution to the bootstrap crossing equations, despite some of our assumptions not being strictly justified.