[Spoilers follow]
I herewith give the solution to last week’s puzzle: mystery diagram #1 represents “uranium”, and mystery diagram #2 represents “harpsichord”.
I suspect, however, that even with the solution in hand, it might take a few minutes to see what the question is…
[Visit here to hear the music…]
Many Worlds Theory 
I won’t even begin to contemplate the second, but how on earth is the first Uranium? Be gentle, I’m not a physicist…
[SPOILER ALERT] Go to your computer keyboard and type the word “uranium” or type the word “harpsichord”. Now look at the diagrams and ponder.
Ahhhhhh, ohhhhhhh….. Well done!
Having typed it and wondering about Google search results for some time … I finally got it 🙂
Well played!