It is as much as I can see, hear, and feel around me at any time. Anything else is purely theoretical, and as such does not exist until I witness it cross the boundary of my universe.

My universe is probably a hemisphere about 200m in diameter, as that is about as far as I can see and about as far as I can hear, anything beyond that is like a backdrop, painting, or white noise.

People enter my universe and leave at will, I think a good model for this interaction would be individual hemishperes coliding into eachother and overlapping. Things in my universe are consitent because I expect them to be, and because the others in my universe expect them to be.

If I could take my universe to a place where it was not being shared, then I could witness it free from outside intervention. I have often thought this is why religious figures wandered off into the dessert for 40 days/nights. There they were free from outside influence and from unwanted expectations.

Time does not exist in my universe, the past and the future are nonexistent. Only change and rate of change exist. Changes to my environment happen progressively and cannot be forced to make big jumps, thus they can be measured. However my changes are not altering with respect to a universal tick, rather to their own individual rate of change.

The biggest motivational factor in my universe is controlled anger. Anger gets things done, it is a positive thing rather than a negative thing. Its direct opposite is complacency and lack of interest. Anger is action, complacency is laziness. This is in terms of thought as well as bodily movement.

Basically my universe is the sum of all of my experiences, some consistency from others universes I have interacted with, plus my reasoning ability