Looks like it is, from the paper:

Popper is named after Karl Poppper, whose idea of falsification [53] inspired our approach, as it did Shapiro’s MIS approach [61]. In fact, one can view our approach as Popper’s idea of falsification, where a failure is a refutation/falsification. In other words, in our approach, a learner deduces what hypotheses cannot be true and prunes them from the hypothesis space, leaving only hypotheses not yet refuted.

Grok is old programmer slang for ‘understanding.’ It’s a shame Elon has subverted such a great piece of linguistic history