This whole idea of moving into different universes is merely a way of controlling your dreams on the grandest scale imaginable.
Instead of making an elf appear outside of your door, you make it so that a land of elf men and women exist.
Instead of teleporting to a room in Harry Potter's house, your creating the entire universe of Harry Potter (using JK Rowling's books as your guides in that creation).
Think of it this way.
Normally when you lucid dream your in "sandbox" mode. You control everything imaginable, and your God.
Sandbox mode is great for awhile, but eventually your going to get bored. Your going to want to enjoy content that you can't just think up on your own.
Thats where this method of control comes in. Instead of being god, you consentually give up your powers.
Its like a video game -- you could always just cheat in video games (use dream control), but you don't. You don't cheat because rules are what make things interesting.
When you lucid dream and enter another universe, your exiting sandbox mode and entering into an actual full fledged video game.
Yes, your sandbox powers still totally exist, but you make a conscious decision not to use them.
The "video game" you enter is a world that someone else has created already.
The "laws" of this universe are the laws that the writer/moviemaker/gamecreator/you has set for the world that he/she/you created.
You become a traveler, and temporarily stop using your powers.
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Again, the separate universes are merely sets of rules that the creator of said universe has put in place. When you enter a portal to any given universe, what your actually doing is consciously accepting that the given ruleset will be the only rule/laws that can effect you when in said universe.
This allows for many things that have only been touched on so far:
- DVrs creating universes for others to explore
- Visiting ancient cultures and actually experiencing them in a very real way
- Playing out full movies
- Having ongoing stories in your LDs -- your halfway through a movie and your REM period ends; two days later you re-enter that same scenario and finish up
- The ability for writers to jump through a portal to a "random" world. The next day they would just have to document what happened - the subconscious would do all the work. (ongoing LD stories would help here)
- etc etc
Endless possibilities.
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Remember though, for any of this to work you have to realize that all the "laws" about lucid dreaming you've heard are wrong.
The only laws are the ones that you truly believe are laws, which is why this technique works at all.