I dreamed that some young men were working on a design for a city enclosed by a dome. They were working out what happens when a projectile such as an asteroid or an enemy rocket hits the dome, skirts along the surface, and then leaves the area without penetrating the dome. They needed a mathematical description of what happens. So I told them how to solve it. (technical details deleted). Funny thing is, when I woke up I realised my solution was correct! How is this possible? When asleep the conscious mind is not working, that’s why most dreams don’t make sense. And my understanding is that tthe subconscious mind can’t do math, it is animalistic. So how could I come up with the correct solution while sleeping?