What's your favorite thing about the natural world? There are lots of things to choose from. The profound tension between natural selection and biological diversity. The fact that no matter how fast you're going, you'll never catch up with a beam of light. The way snowflakes form.
My favorite? It's hard to say, but most days it's the concept of curved spacetime. Those two words, curved spacetime, contain within them some of the strangest and most beautiful ideas in nature: the bewildering truth that the earth is traveling on a straight line around the sun, the fact that clocks run at very slightly different rates at different elevations, and the observation that you can never actually see something fall into a black hole — instead, you watch it turn ever more red until it fades away forever.
It is also the most beautiful mathematical theory ever built, but I respect the fact that not everyone understands that.
Now here's what I really want to write about: your favorite things, whatever they are. Maybe it's a weird flower. Maybe it's a cool experiment you did in high school. Maybe it's Wick rotation (though I doubt it). Leave your thoughts in the comments below, and if you're okay talking to me, let me know how to contact you. I really can't wait to hear all about it.