Paper CLXXXVII: The Pseudoholographic Universe — 7D → (6,3) → 2D → (3,7) → 4D via G₂-Cartan Compression and Fano-Auxetic Unfolding

We establish that the universe arising from the One-Octonion Brane-Bulk G2 Framework is pseudoholographic. The term is earned by a two-stage information architecture that first compresses and then reprojects: the 7-dimensional imaginary octonion space Im(O) is compressed onto the rank-2 G2 Cartan plane via the (6,3) root screen (six positive roots: three short plus three long), and then reprojects from that 2-dimensional transit node onto the 4-dimensional physical brane via the (3,7) Fano-auxetic unfolding. The prefix pseudo is not cosmetic: in standard AdS/CFT holography, information flows from bulk to boundary and stops; here the 2D Cartan screen is a maximum-compression bottleneck from which physical 4D spacetime is reconstructed beyond it. The information-conservation bridge is the G2 ⊂ SO(7) decomposition theorem: 7×3 = C(7,2) = dim(so(7)) = dim(g2) + dim(Im(O)) = 14 + 7 = 21, showing that the 21 Fano incidence pairs enumerate precisely the generators of the ambient rotation group SO(7), which decomposes under G2 into the octonionic symmetry algebra (14 generators) and the fundamental representation (7 generators). A new prediction follows: the entropy of any brane-enclosed region carries a pseudoholographic correction factor f = 21 / |W(G2)| = 21/12 = 7/4 relative to the Bekenstein-Hawking area law. Part of the One-Octonion Brane-Bulk Framework series. Anchor DOI: 10.5281/zenodo.19120873. Community: one-octonion-brane-bulk. Author: Bharathi Dasan Jagadeesan, M.D., University of Minnesota. ORCID: 0000-0002-1143-941X.