# Could information in a boundary be modified once encoded in holographic principle?

There are models of universes where holographic principle has a different correspondence (there is absolutely no reason to assume that this would hold true for all possible universes. You could have a universe there the amount of information in a volume is proportional to the the square of the surface area, or perhaps there is not general correlation at all)

For those models of universes where holographic principle does not even exist (there is not general correlation at all), could we modify that model and make them have a holographic correspondence but keeping all of its original properties?

Also, could the encoded information be modified in the boundary so even if the bulk was a universe that would fit in holography the boundary would be a universe that would be not compatible with holography?

• "There are models of universes where holographic principle has a different correspondence" What models are you talking about? What even motivates these strange, vague, and barely comprehensible questions? It's like asking if you can change the number of sides in a triangle. Maybe yes, maybe no, but it's not really a triangle any more if you do that. – Mitchell Porter Nov 5 '18 at 21:36
• @Sue K Dccia What do you mean by 'holography principle does not exist'? For me such kind of duality is a general rule, the only problem is that maybe the correspondence is not always something like a holography(low dim boundary encodes the high dim bulk) for different systems. Maybe we should just call it a duality instead of holography. – XXDD Nov 8 '18 at 15:06
• @MitchellPorter For example: Consider that string theory is true. Consider that holographic principle applies in our universe. The universe in the boundary would be a copy of our universe. Could there be any theoretical way of changing that information already encoded in the boundary, so the universe there would stop being a copy of our universe and could be transformed into a universe where, for example, string theory wouldn't be right? – user198758 Nov 12 '18 at 11:14
• @MitchellPorter and what do you want to say with the example of the triangle? Couldn't information in the boundary be changed but keeping holographic principle basis? And when you say "maybe no" is it becaise there could be some cases where information encoded in the boundary could not be modified? If yes, in what cases information could not be modified? – user198758 Nov 12 '18 at 11:14
• If you change the number of sides in a triangle, it's not a triangle any more. Similarly, if you change just one member of a holographic dual pair, you don't have a holographic duality any more. The elements of a holographic duality are two dual descriptions of the same thing. There isn't a "copy of our universe" "in the boundary". The boundary description is of the same universe, but with fewer dimensions explicit, compared to the bulk description... – Mitchell Porter Nov 12 '18 at 11:22