GW170817 and the unified propagation speed

In August 2017, LIGO and Virgo detected the merger of two neutron stars, GW170817. The Fermi telescope recorded a gamma-ray burst from the same event 1.74 seconds later. After about 1.3 × 10⁸ light-years, the arrival times limit any speed difference to about 4.2 × 10⁻¹⁶ of the speed of light.

General Relativity accommodates this by building equal speeds into its structure. The paper argues that it gives no mechanical reason why two different kinds of interaction should share one limiting speed.

RSI supplies that reason. The speed of any wave in the Eternal Consonance is fixed by c = √(Ξ/μ), the field's tension divided by its linear density. These do not vary with frequency, so a massive, slow gravitational ripple and a tiny, fast light wave must travel at the same speed, just as every wave on an ideal string travels at the same speed whatever its pitch. Ordinary materials like glass are different, but the vacuum shows no such spread: high- and low-energy gamma rays from distant gamma-ray bursts, such as GRB 090510, arrive together to high precision. They cannot disagree, because they move through the same substance. The theory treats this result as confirming its central premise: gravity and electromagnetism are excitations of a single medium.