it's sci fi, but we haven't ruled out that human brains can't acquire knowledge at rates orders of magnitudes faster than current learning methods. Big advances in neuroscience and linguistics could make this possible.
Right now, the limits on our bandwidth is language and our sensory inputs. It's not completely ridiculous to think we could encode certain kinds of knowledge in more compact forms, and transmit them via an artificial sensory process that has higher higher bandwidth that audio/visual language based learning...