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Superfluidity is a remarkable macroscopic quantum phenomenon that was discovered in 1938 in liquid helium below 2.17 K by Kapitza, Allen and Misener. London was the first person to make the connection with the theory of BoseEinstein condensation (BEC) and degenerate Bose gases developed by Einstein in 1924, and BEC is now understood to be an important ingredient of superfluidity. One of the features of a superfluid is that it exhibits frictionless flow below a certain "critical" velocity, and this is well understood at the level of meanfield theory. However, the inclusion of quantum fluctuations gives rise to a puzzle that has a connection to the Casimir force between two dielectrics in a vacuum. Calculations suggest that the scattering of quantum fluctuations lead to a nonzero drag force at any velocity. Here I will discuss our recent work on calculating the drag force on an obstacle moving through a 1D Bose condensate. Host: David Roberts 