What is the “cosmic calendar”? What are some important scales in the universe? Why is it so hard to judge “importance” of events?
What are galaxy clusters made of, besides galaxies? How can we use them to understand dark matter? And how can we make pretend ones on a computer?
What is “information” in physics? Why do we think it’s preserved, and what happens to information when it falls into a black hole? Why is this a problem?
How do cosmic voids form? What do they teach us about dark energy? What did the early universe look like? What does all this have to do with cupcakes?
What’s the difference between the universe and the multiverse? How can cosmic inflation make bubble universes? Do those universes get different physics? If I travel far enough away, will I meet…myself?