The classic "we're not talking about the same thing" moment in theoretical physics! Left guy's thinking about hypercubes and tesseracts—mathematical structures with rigid geometry that extend beyond our 3D space. Right guy's just vibing with multiverse bubble theory and parallel universes containing alternate versions of reality.
It's like when two physics undergrads try to sound deep at 2AM after watching too many PBS Space Time videos. Neither actually understands the math behind extra dimensions, but they're both nodding enthusiastically anyway. String theorists are somewhere crying into their 11-dimensional equations.