How light moves, and where the wave form comes from: the full derivation

A photon is the smallest piece of light; this page follows one photon.
The textbook wave form ψ = A·ei(kx − ωt), I = |Σψ|², and its intensity pattern come out of the VMS math and patterns below:
λ = S₀/Ad, k = 2π/λ = 2πAd/S₀, and ψ is the sum over routes Σ √weight·e2πiS/S₀, weight the product of the route’s shares (drawn in red over the counted shape, grey).

The textbook wave form has no ħ. It takes the wavelength as given. VMS gives the wavelength:
one step ℓ = S₀/Ad, the distance in which the display action grows by one S₀ (one full turn of what the textbook calls the phase), is the wavelength λ.
That is where ħ lives: S₀ = ∮Ad ds, the n = 1 loop’s own volume, locked to ħ at the electron. (Compare de Broglie’s pλ = h = 2πS₀: the display action ∫Ad ds stands where ∮p·dl stands, and 2πAd where p stands.)

The small figure is the high school drawing: one photon from A to E through three caustics B, C, D, three sizes, one rule. Each numbered circle is exploded below as a zoom (1 to 3 drawn in depth, 4 and 5 enlarged), and each number is a step of the derivation further down. The derivation is the framework’s own math, in order; step 5 ends at the textbook wave form. Nothing on this page is assumed about waves: the wave form is the last line, not the first.

A note on the mathematics. The derivations on the advanced pages draw on two bodies of work that are rigorous and long established but not widely taught: the classification of singularities of smooth maps (Arnold, Gusein-Zade and Varchenko, Singularities of Differentiable Maps, Vol. I, Birkhäuser, 1985) and the asymptotics of wave fields near caustics (Kravtsov and Orlov, Caustics, Catastrophes and Wave Fields, Springer, 2nd ed., 1998). Both have a strong pedigree; both are the province of a small specialist community. For scale, and as background only: SpringerLink records about 1,100 citations of the first book in forty years and about 110 of the second in thirty, and the field’s own international workshops on singularities draw a few dozen participants. The number of people who work with this mathematics is at most in the hundreds, not the thousands.

small photonBCDAEmedium photonBCDAEbig photonBCDAE12345

The zooms (panels 1 to 5)

1the photon: a front, its display area, one steprone step ℓ = λthe frontthe volume hiddenover one stepthe front Σ (A1) advances at c (A2) andhides the patch behind it, the display areaAd = πr² (an area, m²)over one step it has hidden the volumeS = Ad·ℓ = S₀ (a volume, m³)S₀ = ∮Ad ds is the n = 1 loop’s own volume,locked to ħ at the electron.λ = S₀/Ad (volume over area)the wavelength is the display area, inverted.Bigger patch, shorter step.
2the caustic: two fronts of bent space crosstwo fronts of bent spacethe sheet where J = 0the routebent space arriving from two directions:the two fronts cross, and where theycross they form a caustic.rays x = X(q,t), J = det(∂X/∂q)the caustic: the sheet where J = 0the sheet leans: expansion-driven causticsselect a preferred plane (A3); the genericlocal caustic analysed here is the fold(Arnold; the Math Appendix’s case);near it the field is Airy.the photon meets a fold: a tight region,for a time.
3one route in, optional routes outone route inoptional routes outthe pass: the tight regionevery route from one basin to the nextmust cross the ridge; the pass is theforced bottleneck (Closure Math Primer).The tight region is where the photonmeets the fold.a tilted exit costs extra display actionΔS = πr²·ΔLopen while ΔS ≲ S₀ (one S₀ of extra action);amplitude e−ΔS/S₀, share e−2ΔS/S₀normalised at the caustic.big photon: 3 routes, 11 / 78 / 11.same fold, small photon: 7 routes; medium: 5.The patch decides.
4the final distribution at EE27 routes: 3 options at B × 3 at C × 3 at D.each stick is one route; its length isweight = shareB·shareC·shareDits height is where the route ends,yE from the three tiltsgrey: every route counted,P(y) = Σ weight·δ(y − yE)(smoothed half a tilt step)where the photon can end up:a probability of paths.Nothing here is a wave.
5the wave form: the same routes, added as amplitudesthe same 27 routes, each with its display actionψ(y) = Σ √weight · e2πiS/S₀I(y) = |ψ(y)|²S = Ad·Lroute: one S₀ of extra routeis one full turn of the textbook’s phasered: the fringes of the textbook patterngrey: its envelope, the count from 4on a straight stretche2πiS/S₀ = eikx, k = 2πAd/S₀ = 2π/λcarried at c: kx − ωt, ω = kceach term is a textbook plane wave;the sum is the textbook superposition;each term and the sum solve □ψ = 0the wave form is the last line, not the first.

The derivation, step by step (the numbers are the circles in the figure)

1. The photon

A photon is an advancing front that hides a patch of space as it goes. The patch is the display area (an area, m²); what it has hidden along its route is the display action (a volume, m³). Everything about the photon follows from these two.

Ad = πr²   (display area: the orthogonal cross-section the front hides; m²)
S = ∫ Ad ds   (display action along a route: the volume hidden; only ratios of S carry meaning)
S₀ = ∮ Ad ds   (the n = 1 loop’s own volume, m³; the one scale, locked to ħ at the electron)
S/S₀   (closure ∮p·dl = 2πnS₀: one loop, one S₀ of display action, one full turn; the angle the textbook calls the phase)
λ = S₀/Ad   (one step: the length over which the front hides one S₀)

On a straight route the display area is constant, so S = Ad·x and the display action grows evenly with distance:

S/S₀ = (2πAd/S₀)·x = kx,   k = 2πAd/S₀ = 2π/λ,   λ = S₀/Ad   (compare pλ = h = 2πS₀: 2πAd stands where p stands, under the same SI lock that maps S₀ to ħ)

This is already the angle the textbook calls the phase. The wavelength is not given; it is the display area, inverted (a volume over an area). Bigger patch, shorter step.

2. The caustic

Space bent from two directions: two fronts of bent space cross, and while they cross the lattice the photon rides is squeezed. How much the lattice is stretched or squeezed is the Jacobian J of the ray map (its local area transport); a caustic is where J = 0 (Mathematical Bridge Math Appendix, Caustic Formation and Ray Mapping). A caustic environment mandates optionality in the available paths (Mathematical Bridge, Open Path to Photon Sector). Expansion-driven caustics select a preferred plane in the surrounding space (Mathematical Bridge, Electromagnetism; axiom A3), and the generic local caustic analysed here is the fold (Arnold), the case the Math Appendix works through. The photon meets a fold: a tight region, for a time.

Leaving the fold on a route tilted by θ instead of straight on costs extra length over the next stretch L, and extra length costs extra display action:

ΔL = L(1/cosθ − 1) ≈ Lθ²/2     ΔS = Ad·ΔL = πr²·ΔL

A tilted route is an option while its extra action is within the one scale (this page’s reading of the mandated optionality, with S₀ the one scale: a competing route is open while its extra action is within one S₀; the Closure Math Primer carries the optional-path and action-gap ΔS/S₀ picture):

option if ΔS = πr²·ΔLS₀   ⇔   θ² ≲ 2λ/L

That window is the Fresnel-zone construction of optics written in routes (extra path counted against the one scale), with the window’s edge at one S₀ of extra display action (one wavelength of extra route: the first two Fresnel zones). It closes as 1/r²: a bigger display area has fewer ways out of the same caustic.

3. The optional paths

Each option carries a share. The framework weights admissible routes exponentially in their action (Particle Mechanics Math Appendix: the admissible-route ensemble W[r] ∝ e−βS[r]; decays from action gaps, amplitude e−ΔS/S₀·A₀ and probability e−2ΔS/S₀); carried over to one photon at one caustic:

amplitudei ∝ e−ΔSi/S    sharei = e−2ΔSi/S / Σj e−2ΔSj/S    (shares at one caustic add to 100%)

In the drawing the width of each option is its share. The cleanest route is the fattest; the outermost survivor sits at the window edge. Small photon 4/11/22/27/22/11/4, medium 6/24/40/24/6, big 11/78/11.

4. The final distribution: a probability of paths

A route from A to E is one option at B, one at C, one at D. Its weight is the product of its three shares, and where it ends is set by the three tilts over the three stretches:

weight(i,j,k) = shareB(i)·shareC(j)·shareD(k)
yE(i,j,k) = LBC·tan(θi) + LCD·tan(θi+θj) + LDE·tan(θi+θj+θk)
P(y) = Σroutes weight · δ(yyE)    (the grey shape: every route counted)

P(y) is where the photon can end up: a probability of paths. Nothing here is a wave.

5. The wave form

Now add the same routes as amplitudes instead of counting them. Each route carries its display action as an angle, 2πS/S₀; its amplitude is e−ΔS/S₀ at each caustic, the square root of its share, so that routes added without their angles reproduce the count:

ψ(y) = Σroutes √weight · e2πiSroute/S,   Sroute = Ad·Lroute     I(y) = |ψ(y)|²

On any straight stretch the amplitude factor is e2πiS/S₀ = eikx with k = 2πAd/S₀. The count 2πS/S₀ is set where the front is launched and carried with it at c (A2), so the count found at x at time t is the one launched at t − x/c: k(x − ct) = kx − ωt with ω = kc. Each term of the sum is a textbook plane wave; the sum is the textbook superposition; I = |Σψ|² is the textbook intensity.

ψ = Σ A·ei(kxωt),   k = 2πAd/S₀,   λ = S₀/Ad,   ω = kc

Check against the wave equation: every term ei(kx − ωt) with ω = kc satisfies ∂ttψ − c²∂xxψ = 0, and so does their sum, so the route sum built here is a solution of □ψ = 0. The framework reaches the same equation the other way round, by linearising the front’s surface action about a straight path (Mathematical Bridge, Open Path to Photon Sector; Math Appendix, Perturbation Analysis: ∂ttu − c²Δu = 0). Near a fold the stationary-phase integral takes the uniform Airy form u ≈ 𝒜·Ai(αξ), α > 0, ξ the signed distance to the caustic, oscillatory on the lit side (Math Appendix, Caustic Formation and Ray Mapping).

ψ = 0    (the route sum satisfies it; the linearised front derives it)     near a fold ψ → 𝒜·Ai(αξ)

Inside the window the routes differ by up to one S₀ of display action, so |ψ|² carries the fringes of the textbook pattern and P(y) is their envelope: the red curve inside the grey shape. In ordinary space, with many caustics of many strengths and continuous options, the routes’ display actions are uncorrelated; averaged over many such routes, the added intensity approaches the counted envelope. Fringes stay where one regular caustic sets all the display actions the same way. The wave form is the last line of this page, not the first: it emerged from the display area and the caustics, and ħ entered once, as the one scale S₀.

What is derived, what is carried over, what is chosen

LineStatusWhere it stands
Ad = πr², S = ∫Ad ds, S₀ = ∮Ad ds (m³), S₀ = ħ at the electronpublishedMathematical Bridge; Math Appendix, Objects and Units and the electron anchor.
2πS/S₀ is the textbook’s phase (one S₀ of display action is one full turn); λ = S₀/Ad; k = 2πAd/S₀reading of two published linesMath Appendix p. 3: S₀ = ∮Ad ds, the loop’s own display action; p. 27: ∮p·dl = 2πnS₀ with the n = 1 loop identified as 2πS₀ = 2πħ. Read together: the n = 1 loop is one S₀ of display action and one full turn of the textbook’s phase. The compressed training notes carry φ = S/S₀ with closure Sloop/S₀ = 2πn, which would make one S₀ one radian; that is not what the published Appendix says, and this page follows the Appendix. The fringes in the red curve and λ (rather than λ/2π) depend on this reading.
J = 0 at a caustic; caustics mandate optionality; fold, Airy near it; □u = 0 from the linearised frontpublishedMathematical Bridge, Open Path to Photon Sector; Math Appendix, Caustic Formation and Ray Mapping, Perturbation Analysis.
option if ΔS ≲ S₀ (window edge at exactly one S₀)this page’s readingThe Bridge mandates optionality and S₀ is the only scale; the Appendix uses |ΔS|/S₀ as its dimensionless tolerance. The hard edge at one S₀ is where the drawn route set is cut; the exponential share already makes routes beyond it small.
amplitude e−ΔS/S₀, share e−2ΔS/S₀ at one causticcarried overParticle Mechanics Math Appendix, Decays and Widths from Action Gaps (a decay rule) and the admissible-route ensemble (β unspecified); applied here to one photon at one caustic, with β = 2/S₀ for the share (1/S₀ for the amplitude).
weight = product of three shares; yE from the tilts; P(y); ψ = Σ√weight·e2πiS/S₀; I = |ψ|²computedArithmetic on the lines above; the figure is this computation.
ei(kx − ωt) with ω = kc; the route sum solves □ψ = 0derived hereThe count carried at c (A2) gives k(x − ct); each such term and their sum satisfy the wave equation, the same one the Bridge derives from the linearised front.
three caustic positions, seven tilts 3.5° apart, sizes 1 : 1.5 : 3, S₀ at the small photon’s outermost option, which option is taken, independent shares at B, C, D (no memory between pinches), half-tilt-step smoothing, the zoom drawingschosenSee “Chosen for the drawing”.

Chosen for the drawing, not from the framework. Three pinches at 22%, 50% and 70% of the way from A to E (uneven on purpose to show random caustics).
Seven candidate tilts 3.5° apart. The three sizes 1 : 1.5 : 3, chosen so that each photon’s outermost surviving route sits right at the window edge (ΔS grows as (r·tilt)², and r times the last tilt is 3 in every row). S₀ placed at the small photon’s outermost option. Which option the photon takes at each pinch (middle, one up, middle; the same in every row). The shares at B, C and D are multiplied as independent choices: no memory carried from one pinch to the next.
The route counts 7, 5, 3 are relative to that S₀ placement; the r² scaling between them is the framework’s.
The red curve and grey shape are smoothed by half a tilt step, because the drawn routes are 3.5° apart while real routes are continuous.
The zooms are drawings of the same objects, not new claims: the tube in 1 is the volume hidden over one step; the slab in 2 is the pinch figure in depth with the J = 0 sheet drawn in; the pass in 3 is the Primer’s bottleneck picture standing in for the fold, with the big photon’s three exits; 4 and 5 are the big photon’s E column enlarged.

Sources (vms-institute.org/theory). Proposed Mathematical Bridge for the Standard Model and General Relativity: Display Area to Display Action (Ad = πr², S = ∫Ad ds, ratios only), Open Path to Photon Sector (caustics mandate optionality; linearisation gives □ψ = 0), Electromagnetism (expansion-driven caustics select a preferred plane). Mathematical Bridge Math Appendix: Objects and Units (S₀ = ∮Ad ds, units m³; SI lock S₀ = ħ), Perturbation Analysis (□u = 0), Caustic Formation and Ray Mapping (x = X(q,t), J = 0, stationary phase, Airy), the electron anchor (∮p·dl = 2πnS₀, pλ = 2πS₀). Particle Mechanics Math Appendix: Conserved Charge and Families from Admissibility (route weights ∝ e−βS), Decays and Widths from Action Gaps (amplitude e−ΔS/S₀, probability e−2ΔS/S₀). VMS Closure Math Primer (optional paths, forced bottleneck, action gap ΔS/S₀, integer winding on a closed loop). Generator: gen_one_light_proofs3d_v5.py.