How does a shadow really develop? What is the science behind it?
No I was not asking about the Jungian shadow. I did not know what the Jungian shadow is, but I looked it up. I like it. It will be a good term to remember while wriitng. It will help develop a sudden surprise in the character when they realize something about themself that was hidden from their eyes. Of course everyone else reading or the characters in the story might know the surprise, the hidden information the blind character does not see or recognize about themself.
Simply put because an object obstructs the path light travels. Light does not bend and travels in straight lines so it cannot bend around the object to light the area. Shadow is simply the absence of light.
I have noticed, you asked questions about writing and literature, perhaps you are asking about the Jungian shadow?
Well I thought about it, and I think there is no science. The sun is behind something & in front of it is shade. Nothing more.