I just finished reading Leonard Susskind's book,"The Black Hole War". While I had heard of the idea of the universe being a holographic image, I had never before thought it was necessary to take it seriously enough to try to understand it. This book forced me to think about the concept and now I'm really confused.
My understanding, which I'm certain is wrong, is that there is a two-dimensional pixelated boundary that contains one pixel per square planck length that projects a three dimensional something that is our reality.
The book didn't make it clear where these boundaries are. Are they contained in each unit of Plank Space? Or is it the walls of the room I'm in, or the boundary of the Universe? And if the projections do come from the edge of the Universe, doesn't that mean I'm already dead?
The other immediate question is "If our reality is a projection, what gives it substance?"
There are a lot of other questions I have, but this is a good starting point.