Greetings

I've been meaning to ask this question of mine.
When someone casts a sigil 'spell' they basically send out energy into the universe. My question is HOW does the universe recognize the spell's aim and realize it into reality? What causes it to alter reality? How does this happen and by whose decree? Especially when your not actually even making a connection to a deity. Its kinda obscure dont you think?

I hope you can eludicate this doubt of mine.

Al.