Technical Note XLI
From point to density — the wave-mass profile is the enclosed mass of an exponential kernel
The enclosed wave-mass profile used throughout the galactic model, \( M_{wave}(
1. The question
BeeTheory derives Newton’s law from a single particle’s wave function: the (T_2) term of the Laplacian gives the (-1/r) potential, validated on the planets to twelve decimals. For an extended source — a galaxy — the visible matter is a continuous density ( rho_{vis}(mathbf{r}’) ), not a point. The natural extension treats each volume element \( dm’ = \rho_{vis}(\mathbf{r}’)\,dV’ \) as an elementary source carrying its own wave halo, and superposes them.
The question this note answers precisely: what wave density does a single source project, and does its spherical enclosed mass reproduce the profile already in use?
2. The exponential kernel
Let a point source of visible mass \(M\) project a spherically symmetric wave density of range \(\ell\):
The normalization is fixed by requiring the total projected wave mass to be ( lambda M ):
3. The enclosed mass — closed form
Integrating this density inside a sphere of radius \(r\), with \(x = r/\ell\):
The integral \( \int_0^r s^2 e^{-s/\ell}ds = 2\ell^3 – \ell^3\,e^{-x}\,(x^2 + 2x + 2) \) gives, after simplification:
This is exactly the profile used in the 3-parameter model. The factor \( (1 + x + x^2/2) \) is not chosen — it is the order-2 Taylor partial sum of \( e^{x} \) that the \( s^2 \) volume measure necessarily produces.
4. Numerical verification
The closed form was checked against direct numerical integration, and the total mass against the conservation requirement:
| r / ℓ | Numerical ∫ | Closed form | Error |
|---|---|---|---|
| 0.5 | 0.01438768 | 0.01438768 | 2.6×10⁻¹⁷ |
| 1.0 | 0.08030140 | 0.08030140 | 4.2×10⁻¹⁷ |
| 3.0 | 0.57680992 | 0.57680992 | 1.1×10⁻¹⁶ |
| 8.0 | 0.98624603 | 0.98624603 | 0.0 |
| ∞ | 1.00000000 | λ (= 1) | conserved |
5. From one source to a density: the convolution
If every visible element projects this same kernel, the total wave density at a point \( \mathbf{r} \) is the convolution of the visible density by \(K\):
As a consistency check, convolving a near-point source (a narrow Gaussian of width \( \varepsilon = 0.05\,\ell \)) reproduces the spherical enclosed mass to better than 1%, the residual vanishing as \( \varepsilon \to 0 \):
| r / ℓ | Convolution (3D) | Closed form | Rel. error |
|---|---|---|---|
| 0.5 | 0.014294 | 0.014388 | 0.7% |
| 1.0 | 0.080072 | 0.080301 | 0.3% |
| 3.0 | 0.576530 | 0.576810 | 0.0% |
| 5.0 | 0.875243 | 0.875348 | 0.0% |
6. Why this matters
The galactic model is no longer “a baryonic term plus an empirical wave term. The wave term has a single, transparent origin — an exponential kernel of range ℓ, applied to the visible density exactly as a sphere is the sum of its atoms. This converts a postulate into a derived consequence, and isolates the only remaining freedom.
Three consequences follow:
- The profile is forced, not fitted. Given an exponential kernel, the \([1-(1+x+x^2/2)e^{-x}]\) shape is the unique enclosed-mass law. No degree of freedom hides in it.
- The same logic spans scales. Point → sphere (Cavendish) → continuous density (galaxy) is now one operation — a convolution — whose spherical limit returns the verified planetary case. The point-to-density step is mathematically closed.
- The freedom is reduced to ℓ. Everything is now carried by the kernel range \( \ell \). In the spherical/point limit \( \ell \) is universal. The model writes \( \ell = c\,R_d + \ell_{floor} \) with \( c = 0.16 \) nearly negligible — which raises the sharp, testable question of whether a single universal range \( \ell_{floor} \) suffices, collapsing the model from three parameters to two.
This note establishes the kernel and its spherical limit. It does not yet show that convolving a realistic disk density (Freeman profile + extended gas) with a single universal ( ell_{floor} ) reproduces observed rotation curves. That disk calculation — and the cluster-scale test — are the next steps and are not settled here.
BeeTheory.com — From point to density: the exponential kernel · Initial generation: 21 May 2026 with Claude.ai · © Technoplane S.A.S. 2026