  We compute the low-lying spectrum of 4D SU(2) Yang-Mills in a finite volume
using quantum simulations. In contrast to small-volume lattice truncations of
the Hilbert space, we employ toroidal dimensional reduction to the
``femtouniverse" matrix quantum mechanics model. In this limit the theory is
equivalent to the quantum mechanics of three interacting particles moving
inside a 3-ball with certain boundary conditions. We use the variational
quantum eigensolver and quantum subspace expansion techniques to compute the
string tension to glueball mass ratio near the small/large-volume transition
point, finding qualitatively good agreement with large volume Euclidean lattice
simulations.
