'Nothing' in the context of existence is not relative, it is absolute nothing, not even nothing in existence!
We live in space-time where space and time are integrated. We observe motion and change based on changes in space coordinated with time. This is what allows cause and affect, since the vector of time is to the future. Cause is now and the affect is in the future. This is easier to see when connected space also shows changes with time; allows us to infer cause and affect.
But if space and time were not connected, then the rules of cause and affect can change. For example, say I am playing chess and are about to make a move. I am touching the bishop but I pause. Before I move, I think it through and look to the future; imagination, to see all the potential affects from this initial cause; my move. I notice I will be trapped six moves down the line. I saw the future, so now I change the present; use a different move with a better ending. Which is the cause and which is the affect?
The answer has to do with observational reference. An outside person cannot read my mind, nor am I narrating my thought train so my opponent can hear. The outsiders will see me about to move, pause and then move. Then the game goes on; cause and affect. But in my imagination the initial cause; original move, led to a cascade of affects, that showed me that this would not be a good move. That realization; new cause, then led to the affect of me changing my mind; new move This affect is then assumed to be the cause of my opponents move, by third parties.
The imagination, where space-time is not limiting, cannot be seen under the microscope since it involves movements of data which have no physical nature. Yet this movement of data can still impact material cause and affect in ways that may not be obvious in the third person. Faith cannot be seen like a plant, other than by body language, yet it often sees the future and adjusts the present to meet the future on time.
In the case of a realm, where space and time are not connected; informational realty, the universe can appear from a glimpse in the future and an adjustment in the present. It is like the author who writes the happy ending first and now they can do whatever they wish everywhere else in the book, since in the end they all live happily ever after.
2-D thought is based on cause and affect, but 3-D thought involves cause, affect, cause and affect, cause and affect. This is where the imagination comes in; space and time separated added to space-time connected. If space and time were separated we would be in a realm of maximum complexity or maximum entropy. This maximum complexity allows not only the laws of nature, but all the potential of the imagination. If we lower the complexity to just the laws of nature the entropy will lower and give off energy; let there be light. The second law by increasing the entropy of the universe gradually returns space-time back to the realm of disconnected space and time. The second law connects the two realms; material with informational.