I am trying to craft a story around the idea that, when we dream, we actually access another indeterminable plane of existence, a kind of repository into which the dreams and thoughts of all living things are poured and shared across different minds, within which many other abstract ideas and concepts can also be found...
...accessing this plane is not unlike astral projection, and lucid dreaming can allow you to travel across this plane rather than being a casual observer of it; mastering this ability allows you to influence it in dynamic ways that most dreamers can't, able to do everything from appear in other people's dreams to communicate with them, access other people's memories, witness abstract concepts and interpret what they truly mean, make and/or decipher prophecies, even discover the dreams and thoughts of people long dead that have outlived them in this place...
...as you can see, there are a lot of different ideas being tied together here, suggesting dreaming is capable of much more than what we believe it to be. I'm even playing with the ideas of, say, accessing genetic memory this way, or extrapolating future events by looking at past memories and events to make educated guesses...things that one might not even necessarily associate with dreams at first, but still things I think figure into it in natural, meaningful ways.
So I guess my main question is:
Is there a precedent for this? Do ideas like this exist already in science, or mythology, folklore, literature, pop-culture, etc.? This, of course, kind of skirting around obvious but circumstantial parallels (stuff like INCEPTION and NIGHTMARE ON ELM STREET, etc.)
I would like to create an extensive mythology for this - "place" - based on ideas that already exist and have some sort of traceable history found in fact, cultural or otherwise, so that it lends an air of legitimacy to it, instead of seemingly made up wholesale.
If anyone happens to know how to answer this question and build on it in a meaningful way, please discuss: it would be greatly appreciated.