  Swimming in low-Reynolds-number fluids requires the breaking of time-reversal
symmetry and centrosymmetry. Microswimmers, often with asymmetric shapes,
exhibit nonreciprocal motions or exploit nonequilibrium processes to propel.
The role of surrounding fluids has also attracted attention because
viscoelastic, non-Newtonian, and anisotropic properties of fluids matter in
propulsion efficiency and navigation. Here we experimentally demonstrate that
anisotropic fluids, nematic liquid crystals (NLC), can make a pulsating
spherical bubble swim despite its centrosymmetric shape and time-symmetric
motion. The NLC breaks the centrosymmetry by a deformed nematic director field
with a topological defect accompanying the bubble. The nematodynamics renders
the nonreciprocity in the pulsation-induced fluid flow. We also report the
speed enhancement by confinement and the propulsion of another symmetry-broken
bubble dressed by a bent disclination. Our experiments and theory elucidate
another possible mechanism of moving bodies in complex fluids by spatiotemporal
symmetry breaking.
