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Accepted · first revision · record

Title: Infrared phase of SU(2) gauge theory with two adjoint Weyl fermions
Plain: A close relative of QCD, with matter particles of a different type, has several candidate behaviors at long distances. Which one it chooses is unknown.
Precise: 4D $\mathrm{SU}(2)$ gauge theory with two massless Weyl fermions in the adjoint representation (equivalently one adjoint Dirac fermion) has $\mathrm{SU}(2)_{R}$ flavor and $Z_{8}$ discrete chiral symmetry. Determine its deep-infrared phase among the candidates: confinement with $\mathrm{SU}(2)_{R} \to \mathrm{U}(1)$ breaking (a $\mathrm{CP}^{1}$ sigma model), confinement with massless composite fermions, or an interacting CFT (Cordova and Dumitrescu 2018; Anber and Poppitz 2018).
Settled by: Lattice simulation of SU(2) with one adjoint Dirac fermion at small mass and large volume, measuring the spectrum, chiral condensate and mass anomalous dimension.
Kind: well-posed
Answer type: classification
References: (empty)
Literature status: contested
Status note: Lattice studies (2014-2024) report near-conformal spectra with a large mass anomalous dimension, not conclusive between the candidates.
Posed since: (empty)