Day 140: Special Relativity

We whiteboarded our last photon model of light questions, and the best part of today was the questions. That seems to be my new theme; their questions are so well-crafted and incisive that they should be celebrated. What are the different ways we can define intensity? Why can't an electron just absorb some of the energy of a photon?

And then we moved to special relativity, and the questions kept coming: How is this related to time travel? How much energy would it take to accelerate me to close to the speed of light? What does it mean that "that astronaut" traveled 0.5 seconds into the future?

Now they want to study a lot more special relativity.