Λ Ground Mode of the Cosmic Boundary
Λ Ground Mode of the Cosmic Boundary
Einstein introduced Λ in 1917 to hold the universe static. When Hubble proved expansion, he removed it, calling it his “biggest blunder.” A century later, standard cosmology revived Λ as dark energy. This note completes the arc: there is no dark energy nor mysterious force. Λ is set by the ground‑mode eigenvalue of the cosmic boundary; the geometry of the universe itself driving expansion. Einstein was right the first time, for reasons then unknown. The Möbius surface selects half‑integer modes; the lowest yields Λtop = 2/R², where R is the curvature radius of S³. The observationally inferred Λobs differs by a factor of 3/2, obtained through Gauss–Codazzi embedding under totally geodesic embedding and isotropy; the surface‑to‑eigenvalue identification is motivated from three directions.