TY - JOUR AU - Stephen Eckel AU - Avinash Kumar AU - Theodore Jacobson AU - Ian Spielman AU - Gretchen Campbell C2 - Physical Review X DA - 2018-04-19 DO - https://doi.org/10.1103/PhysRevX.8.021021 LA - en M1 - 8 PB - Physical Review X PY - 2018 TI - A supersonically expanding Bose-Einstein condensate: an expanding universe in the lab ER -