  We study, for the first time, the Casimir effect in non-Abelian gauge theory
using first-principle numerical simulations. Working in two spatial dimensions
at zero temperature we find that closely spaced perfect chromoelectric
conductors attract each other with a small anomalous scaling dimension. At
large separation between the conductors, the attraction is exponentially
suppressed by a new massive quantity, the Casimir mass, which is surprisingly
different from the lowest glueball mass. The apparent emergence of the new
massive scale may be a result of the backreaction of the vacuum to the presence
of the plates as sufficiently close chromoelectric conductors induce, in a
space between them, a smooth crossover transition to a color deconfinement
phase.
