Robertson 1934 in every basis ▸

NRS³ — every box has its star

On the box dx × dy × dz each axis carries the pair transport T and position P. At the maximal current state of the cube, the product of the maximal current states of the axes, their fluctuations open the angle θNRS(d): zero only with 2 or 3 sites, never zero from 4 on. The quantum lives on boxes with 4 or more sites on every axis; an axis with 2 or 3 sites is marked in red. It runs on its own: every 5 s a new random box, 4 to 25 sites per axis, with transport moving Ψ and the view turning. Change the box and the star deforms. Drag either panel to turn both.

The box: Ψ on every site

size |Ψ|² · colour phase

The star of the box

δT and δP of each axis

The band of the quantum

At the maximal current state of the cube every axis with 4 or more sites opens between θNRS(4) and arccos(1/C∞), never on the ceiling: the shape changes from box to box, the band does not. ○ θNRS(d) at the maximal current state of the cube · ● θ at Ψ(t). The page runs on its own: every 5 s a new random box, 4 to 25 sites per axis, with transport on. Ψ(t) starts at the quantum and leaves it; the band stays. Press Tour to stop on a box, Transport to pause.

The octahedron of the quantum (D25, D37e)

drag to turn · dashed: d → ∞

Each axis with d sites carries the excess over saturation δ(d) = CNava(d) − 1, zero only with 2 or 3 sites (D25). Put a vertex at ±δ on every axis: the octahedron of the box. The regular 4 × 4 × 4 gives the smallest, δ(4) ≈ 0.00848 on every axis; no box reaches the dashed one of d → ∞, δ∞ = C∞ − 1 ≈ 0.13572 on every axis. Its volume is (4/3)·𝒱, with 𝒱 = δ(dx) δ(dy) δ(dz) the volumetric quantum and δ(4)³ ≤ 𝒱 < δ∞³ (D37e).

δ on x, y, z–
𝒱 = δxδyδz–
𝒱 / δ(4)³ (floor = 1)–
𝒱 / δ∞³ (ceiling = 1, never)–

Speed and the quantum (D44)

|v(t)| against θ(t), one panel per axis

The speed of an axis is v = ((d − 1)/2)·⟨K⟩, K = i[T, P] (D38). Minimum uncertainty (θ = 0) is possible only up to v*(d); on the band Ϙ(d) = (v*(d), 1] every state has a forced defect, and at the cone v = 1 the angle is exactly the quantum θNRS(d). Press Transport: Ψ(t) starts at the quantum and leaves it as it slows down.

Exact in Lean: v*(4) = 3(√5 − 1)/4 (D23f, D23g, D43); the band is empty for 2 or 3 sites and non-empty from 4 on (D44); θ = θNRS(d) at v = 1 (D48). Numerical: v*(d) for d ≥ 5 and the dotted envelope (the smallest angle at each speed). The horizontal scale is stretched above v = 0.9.

family (D37i)–
orbit under axis permutations–
signed permutations keeping every angle–
the quantum–
axissitesθ(t)θNRS(d) at t = 0 CNava = 1/cos θNRSσTσP(t)⟨P⟩(t)

Exact in Lean (repository nava-robertson-schrodinger): the angle is angleG = arccos(‖⟨δT, δP⟩‖ / (σT σP)), the same formula as here, with cos θNRS(d) = 1/CNava(d) and θNRS(d) = 0 ⇔ d ∈ {2, 3} (D37b); the band θNRS(4) ≤ θNRS(d) < arccos(1/C∞), C∞ = √(π²/3 − 2), holds at the maximal current state of the cube and at its 48 images under turns and reflections (angleNRS_spectrum_bounds, D48; octahedral_symmetry, D37h), not at Ψ(t) under transport (angleAxis at any state); at the maximal current state of the cube each axis has its own angle and the axes commute (D37, D37h); the three families, orbits of 1, 3, 6 boxes and 48, 16, 8 angle-keeping symmetries, and the quantum is never erased from 4 sites on (D37i); transport spreads at most one site per step (D37f). The numbers on this page are computed in your browser from the same matrices (T = path adjacency / ρd, P = centred position); the star is drawn schematically, one axis per direction, with the true angles and lengths; the hull is its convex envelope.