What would the Sun sound like if we could hear it? Does any noise at all happen in the universe? What’s the biggest sound of all?
Why does the vacuum of spacetime have energy? How much energy does it have? What prevents us from using it to do anything useful?
How do we actually define voids? Are there regions within them that are truly empty? What would it be like to be inside one?
Part 2 of 2! What are the modern constants of nature? Is the universe fine-tuned for life? Does the multiverse or string theory explain the origins of the constants?
Part 1 of 2! How do fundamental constants appear in physics? Why are they so important? Why do we care where they come from?