Passing the Einstein Test: PPN Gamma = 1

validation
relativity
mathematics
Analytical confirmation that the acoustic metric reproduces General Relativity in the Solar System.
Author

Raúl Chiclano

Published

November 24, 2025

The Challenge

Any alternative theory of gravity faces a deadly filter: The Solar System Tests. General Relativity predicts that light bends around the sun by exactly \(1.75''\) arcseconds. Many scalar theories predict half that value (\(\gamma = 0\)).

We used symbolic calculus (SymPy) to derive the Post-Newtonian Parameter \(\gamma\) for the Dynamic Background acoustic metric.

The Result

The derivation (Simulation 08) yielded an exact match:

\[ \gamma = \frac{g_{rr}^{(1)}}{g_{00}^{(1)}} = 1 \]

This confirms that the fluid density gradients curve space and time in the exact proportion required by Einstein’s theory.

The MOND Regime

Furthermore, Simulation 09 revealed that the effective Lagrangian naturally contains non-linear terms (\(X^2\)) that mimic MOND behavior at low accelerations.

Crucially, Simulation 10 confirmed that these non-linear corrections are suppressed by 38 orders of magnitude in the Solar System, ensuring that local physics remains Newtonian/Einsteinian while galactic dynamics exhibit dark matter-like effects.

Status: Phase 2.1 Complete. The theory is safe at local scales.