Phase diagram of SU(2) with 2 flavors of dynamical adjoint quarks

We report on numerical simulations of SU(2) lattice gauge theory with two flavors of light dynamical quarks in the adjoint of the gauge group. The dynamics of this theory is thought to be very different from QCD—the theory exhibiting conformal or near conformal behavior in the infrared. We make a high resolution survey of the phase diagram of this model in the plane of the bare coupling and quark mass on lattices of size 8³ × 16. Our simulations reveal a line of first order phase transitions extending from β = 0 to β = β_c ~ 2.0. For β > β_c the phase boundary is no longer first order but continues as the locus of minimum meson mass. For β > β_c we observe the pion and rho masses along the phase boundary to be light, independent of bare coupling and approximately degenerate. We discuss possible interpretations of these observations and corresponding continuum limits.