The Universe as a Projection: The Holographic Principle, Dimension, and the Observer

This article proposes a generalisation of the holographic principle beyond its original formulation as a property of black holes and quantum gravity. The core thesis is that hypothetically, any n-dimensional surface can be regarded as a screen (projection) for events in (n+1)-dimensional space, and that the perceived dimensionality of the Universe depends on the cognitive structure of the observer. We humans are "constructed" to perceive a three-dimensional world, and therefore see the Universe as 3D. Other forms of consciousness (or other forms of matter from the 7FM model) may be "tuned" to 4D, 5D, and beyond — but this is, presumably, the same Universe, in the same place. The concept unites three independent lines of thought: the holographic principle ('t Hooft, Susskind), Donald Hoffman's interface theory, and the Infinite-Dimensional Multiverse Model (IDM) with its principle of choosing the description level G. The accompanying comparative article demonstrates that Hoffman's approach and the author's do not oppose but complement each other, describing the interface of perception and the geometry of the multiverse as two levels of one reality. The article also shows that the proposed concept is consistent with contemporary research in holography, quantum information, and cognitive science, including work on observer-dependence of holographic screens (Bousso et al., 2016) and on the role of the observer in holographic maps (Reinking et al., 2025). Verification parameters (IPA, ΔX, K_XY, T) are proposed, and consequences for physics, cognitive science, philosophy, and technology are discussed. The article is conceptual in nature, addressed to physicists, philosophers, cognitive scientists, and methodologists of science, and is open to critique and further development.