Physicists coax superfluid to have ‘negative mass’

The matter flows against the pushing force.

Scientists reproduce conditions from early universe

Physicists have successfully reproduced a pattern resembling the cosmic microwave background radiation in an experiment which used ultracold cesium atoms in a vacuum chamber. This is the first experiment which recreates at least some of the conditions from the Big Bang. “This is the first time an experiment like this has simulated the evolution of structure in the early universe,”

First frictionless superfluid molecules created

Superfluidity is a weird property, by all standards. Basically it is a state of matter in which all the viscosity of a fluid vanishes; what happes is you take some atoms, and you chill them, and then chill them some more, until they get close to absolute zero (-273.15 degrees Celsius, the temperature below which nothing can exist). After this,