Paper 10 of the Holographic Cosmology Series. Derives wave function collapse from the holographic boundary's gravitational decoherence mechanism. Content restricted pending patent applications.
Attention: This version is preliminary and contains errors that will be corrected in subsequent publications. A mechanism is proposed for the collapse of the wave function as a topological restructuring of the holographic barrier—the surface separating realized (classical) and unrealized (superpositional) configurations. Collapse occurs when the information load of the superposition exceeds a threshold determined by the geometry of the barrier. The geometry is described by a series of information dimensions derived from the energy balance of the Universe: the smooth screen D_0 = 2; the information dimension of the barrier D_1 = 2 + Ω_b ≈ 2.049; the matter dimension D_m = 2 + Ω_m ≈ 2.31; the total dimension of rendered space D_3 = 2 + Ω_tot = 3. The dimensional balance formula 2 + Ω_b + Ω_c + Ω_Λ = 3 links the flatness of the Universe (Ω_tot = 1) to the integrality of the dimension of observed space. The theory yields two independent falsifiable predictions with no free parameters: the scalar spectral index n_s = 0.9754 ± 0.0010 (theoretical uncertainty) and the superlinear scaling of the decoherence rate of GHZ states Γ ∝ N^(1+α_1), α_1 ≡ Ω_b = 0.0493 ± 0.0020, accessible to testing on existing quantum processors. The work is positioned within the information-gravitational program (Jacobson 1995; Dorau–Much 2026) and reproduces the latter's result as the limiting case α_1 → 0. Recent experimental evidence for the exponential law of collapse (RCE 2026; non-local gravity 2025; XENONnT 2026) is shown to be consistent with the mechanism. The dynamical foundation of the mechanism (Lagrangian, topological transition weight) is given in the companion work. Keywords: measurement problem, collapse of the wave function, holographic principle, fractal dimension, spectral index, decoherence, GHZ states.
Gravitational decoherence and gravitational wave function collapse are presented as two related but conceptually distinct ideas. Gravitational decoherence measures the effect of gravitational perturbations on the evolution of quantum systems, in particular their progressive lack of coherence. Gravitational wave function collapse starts with the assumption that the Schr¨odinger equation is not entirely right, and must be supplemented with extra terms, which cause the (random) collapse of the wave function; the collapse is then linked to gravity. Some of the most popular models are reviewed, with an emphasis on their conceptual status, stage of development, and open questions.
A more detailed analysis of the measurement problem continues to support the position taken by Shimony and the author that collapse of the wave function takes place in an objective manner in the rhodopsin molecule of the retina. This casts further doubts on the theories involving a spontaneous localization collapse process or a no-collapse decoherence process taking place in the visual cortex in a subjective fashion. The possibility is then raised, as per Anandan, as to whether the solution of the measurement problem in quantum theory allows one to address the problem of quantizing gravitation.
We propose a double-slit photon interference experiment conducted across three gravitational conditions (1g, ~0g, 0.16g) to test whether gravitational field strength modulates wave function collapse behaviour. This proposal does not assume wave function collapse is ontologically real; it tests whether effective collapse behaviour—operationalised as interference fringe visibility and decoherence rate—varies with gravitational context. A secondary experiment introduces information accessibility as a variable, testing whether the causal availability of which-path information affects collapse statistics differently across gravitational conditions. Null results would place strong upper bounds on gravitationally induced collapse models, constraining Penrose-type theories. Positive results would provide the first direct experimental evidence for a gravitational component in quantum state reduction. Keywords: wave function collapse, quantum decoherence, gravity, Penrose objective reduction, measurement problem, double-slit experiment, microgravity
Starting from an idea of S. L. Adler [in Quantum Nonlocality and Reality: 50 Years of Bell's Theorem, edited by M. Bell and S. Gao (Cambridge University Press, Cambridge, England 2016)], we develop a novel model of gravity induced spontaneous wave function collapse. The collapse is driven by complex stochastic fluctuations of the spacetime metric. After deriving the fundamental equations, we prove the collapse and amplification mechanism, the two most important features of a consistent collapse model. Under reasonable simplifying assumptions, we constrain the strength $\ensuremath{\xi}$ of the complex metric fluctuations with available experimental data. We show that $\ensuremath{\xi}\ensuremath{\ge}{10}^{\ensuremath{-}26}$ in order for the model to guarantee classicality of macro-objects, and at the same time $\ensuremath{\xi}\ensuremath{\le}{10}^{\ensuremath{-}20}$ in order not to contradict experimental evidence. As a comparison, in the recent discovery of gravitational waves in the frequency range 35 to 250 Hz, the (real) metric fluctuations reach a peak of $\ensuremath{\xi}\ensuremath{\sim}{10}^{\ensuremath{-}21}$.