TU-GUT-SYSY v3 – Final Form One Principle, Zero Parameters: Spacetime exists only where electromagnetic vacuum entanglement entropy can still increase

This 9-page paper is the definitive and final version of the TU-GUT-SYSY programme developed by Simon Soliman (independent researcher, Rome). Starting from the single ontological statement “Spacetime exists only where and while the entanglement entropy of the electromagnetic vacuum can still increase,” the entire reasoning chain is presented exactly as it emerged, step by step: laboratory superconductors (measurable weight reduction when S = S_max locally) “This is the revised version (v3.1, 5 December 2025) – Section 3 now contains the explicit derivation of ρ_DM = 0.300 GeV/cm³ from vacuum EM entanglement entropy.” galactic dark-matter density ρ_DM = 0.300 GeV/cm³ derived from magnetic coherence (zero tuning) astrophysical black holes as regions of globally saturated entanglement (no interior spacetime, no singularity, T_Hawking = 0 exactly) late-time cosmic acceleration from nearly uniform residual entanglement (dark energy) cosmic plasma as the directly observable macroscopic laboratory of the process All major gravitational and cosmological phenomena are quantitatively reproduced with exactly zero free parameters and no additional fields. Previous versions: v1 → https://doi.org/10.5281/zenodo.17794324 v2 → https://doi.org/10.5281/zenodo.17795466 Independent work – no affiliation, no funding Contact: [e-mail] Explain ρ_DM derivation Compare to ΛCDM model