theorem friction_from_vri (T χ σ_sq : ℝ) (hχ : 0 < χ) (hvri : σ_sq = T * χ) : σ_sq / χ = T := by rw [hvri, mul_div_cancel_right₀ T (ne_of_gt hχ)]
thesis/CESProofs/Dynamics/FluctuationResponse.lean:282
## Corollary 3b.2: Mode-Specific Friction Measurement