>[!warning] >This content has not been peer reviewed. # RST Refractive Lensing — Solver (Disformal Extra Bending) This script implements the **Refraction Identity** to show that the **disformal term** produces the extra bending required for galaxy clusters — without dark matter. **Derivation:** [[RST Lensing (Disformal)]]. The physical metric for light is $\tilde{g}_{\mu\nu} = e^{2q}g_{\mu\nu} - (e^{2q} - e^{-2q})\, A_\mu A_\nu.$ The "bending boost" is the relational reciprocal of the update-speed drop with workload $q$. --- ## Calculation logic --- ## Logic 1. **Newtonian potential** $\phi_N \propto 1/r$. 2. **MONDian workload** $q \sim \sqrt{\phi_N \, a_0}$ (simplified weak-field). 3. **Bending boost** $1 + (q/\phi_N)$ from the disformal update-lag. 4. **Total deflection:** $\alpha_{\text{RST}} = \alpha_{\text{GR}} \times \text{boost}$. So RST lensing exceeds baryons-only lensing by the substrate's **bandwidth congestion** (Refraction Identity). Zero free parameters in the gravity sector.