General relativity predicts that the curvature of spacetime induces spin rotation in parallel transported particles. We unfold Unruh’s analogue gravitational image and consider quantized vortices embedded in a two-dimensional superfluid Bose-Einstein condensate. We show that such vortices behave dynamically like charged particles with spin in the gravitational field. The presence of vortex spins in superfluids complements Onsager’s predictions about the quantization of circulation and suggests potential quantum technological applications of rotating superfluids.
