Space Density Theory: A Unified Scalar Field Framework for Dark Matter, Dark Energy, and the Hubble Tension

Space Density Theory: A Unified Scalar Field Framework. Full technical paper covering: rotation curve fits for 172 SPARC galaxies (81.4% pass rate vs MOND's 78.5%, same free parameters per galaxy); derivation of MOND acceleration scale as SDT phase transition critical point; RAR scatter 0.116 dex vs MOND 0.117 dex; Hubble tension reduction from 3.7 to 0.5 sigma; N-body validation with time-dependent memory term (analytic M_eq=0.806 confirmed by simulation at 0.80); 6 author-run simulation figures; 12 falsifiable predictions; three-category Section 12 (resolved/testable/open). Corrected from v2: SPARC pass rate updated from 87% to 81.4% following definitive rerun.