Here are the details of the experiment with the helium atom(s):

Trustcott’s experiment involved creating a Bose-Einstein Condensate of around a hundred helium atoms. He conducted the experiment first with this condensate, but says the possibility that atoms were influencing each other made it important to repeat after ejecting all but one. The atom was passed through a “grate” made by two laser beams that can scatter an atom in a similar manner to a solid grating that can scatter light. These have been shown to cause atoms to either pass through one arm, like a particle, or both, like a wave.

A random number generator was then used to determine whether a second grating would appear further along the atom’s path. Crucially, the number was only generated after the atom had passed the first grate.

The second grating, when applied, caused an interference pattern in the measurement of the atom further along the path. Without the second grating, the atom had no such pattern.

In the bizarre world of quantum mechanics, events rippling back in time may not seem that much stranger than things like “spooky action at a distance” or even something being a wave and a particle at the same time. However, Truscott said, “this experiment can’t prove that that is the wrong interpretation, but it seems wrong, and given what we know from elsewhere, it is much more likely that only when we measure the atoms do their observable properties come into reality.”

These seemingly unusual properties have even lead theoretical physicists to pose models where the present effects the past.  Trippy!

We hope you enjoyed the details of this bizarre experiment.

thanks to iflscience.com for the great info