Infinite realities
Brain storming head space.
Book; The Long Earth by Terry Pratchett and Stephan Baxter
Premise; a little box, a Stepper, (powered by a potato) can step the maker one world to the east or west. And continue to do so. (bare iron does not step). Each new world is almost identical, except there are no humans. With each step, the variations increase and different evolutionaryand situational conditions are given. (new life, similar life, new plants, variations in climate, different cataclysms, etc.)
some naturally step and not get sick, (nausea from stepping with a box), some have learned of wormholes that will step thousands of steps,some people cannot step at all. One reality, the Earth was not there. It had been taken out by a meteor. It is called, The Gap.
Book: the Death Gate Cycle by Margarett Weis and Tracy Hickman
Seven different connected realities, each a different combination of the major elements, is being threatened by powerful mages and Sentinels looking for something specific. It is a kind of race to get through Gates in a survivalist prison world setting.
two main characters are opposing "mages" with different styles of magic. One alters the immediate environment to accomplish his needs, the other modifies the environment In General to create the possibilities of what he needs.
the part of that story that intrigues me is that there is a prison room where the second mage had eliminated all possibilities of escape, so there was nothing to manipulate to escape.
Book: A brief illustrated History of Time, Stephan Hawking
Time travels in two cones that are attached at their tips. That point is Now, he open ends are Past and Future. Every single thing that could have affected you is in the past cone, it widens the further away it is because that represents the totality of things that have affected this Now. Every thing that you can possibly affect or have an affect on lies in the future cone. Anything too far away will never affect the Now, and it then is outside the cones. You will never even know it exists. Everything you can perceive is now in your past cone.
Now, instead of infinite realities being just endless left and right, what if every single event produced varying probabilities of alternate realities? intersection with others, making a decision, collisions.
This is where it gets tricky. to see this type of infinity, imagine one life line, at every point, there are an infinite lines of probability shooting off in all directions. And each one of those lines has its own points and lines of probability shooting off.
The first line is now a really fuzzy line, the second set are now everywhere. Now add in not just you, but Everyone interacting and making points and lines and probabilities.
There are realities where everything is EXACTLY the same right up until This moment, his Now. Now you make a decision. So, which are we in now?
Ever notice when something seems off? You swear you put something someplace and now it's not there? Do you ever remember something a certain way but others don't? Suddenly, something that used to be hard is a piece of cake now and you don't know why?
I don't think you are in that reality anymore. You have Stepped.