A joint analysis of lattice simulation data points to the emergence of quarkyonic matter, an intermediate state between confined hadrons and quasi-free quarks. The duality of this regime imposes a robust constraint on the behaviour of the distribution functions, and the reviewed results are consistent with that prediction.

The work first reviews quarkyonic matter from the standpoint of the distribution functions and then examines recent lattice data for two-color QCD in (1+1) and (3+1) dimensions at finite baryon number density, as well as QCD in (3+1) dimensions at finite isospin density. Added to these is the equation of state inferred from astrophysical observations.

Taken together, these results reveal a picture consistent with the emergence of quarkyonic matter in lattice simulations, according to the authors. The interpretation, however, is not yet a direct test of the dual state.

A more direct test would come from future lattice calculations of baryon- and gauge-invariant quark momentum distributions at high density. Those results would allow a more precise check of the proposed interpretation.