W(x, p)

She's been in superposition since 2023.

A live phase-space experiment exploring coherence, interference and the moment observation becomes reality.

Enter the chamber See the physics

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Initialising chamber
3210−1−2
−3−2−10
−3−2−10123
|ψ⟩
W(x, p)
Drag to rotate
Unobserved / coherent
06Components
0.984Purity
−0.312Negativity
30:00Observation window
View live telemetry
01

The experiment

Not an animation of a cat state — an actual one. Change it here and the chamber above changes with it.

Wigner W(x,p)

96 × 96 grid
Hover the plot to read the distribution—
Components N = 6
Separation α 3.20
Decoherence κ 0.020
01 / STATE

A real cat state

An equal superposition of N coherent states on a ring in phase space. The lobes you see are the components; the ripples between them are interference, and they only exist because the cross terms are kept.

|ψ⟩ = 𝒩 · S(r) · Σₖ |α e^(i(2πk/N + φ))⟩
02 / EVIDENCE

Wigner negativity

Push κ up and watch the fringes die while the lobes survive. That is decoherence: the parts stay, the betweenness goes. Negativity falls to zero and the state becomes an ordinary mixture.

∫W<0 |W| d²β  →  1/π for a two-lobe cat
03 / COLLAPSE

Measurement, honestly

Observing draws one sample from the marginal P(x) — the real distribution, not a coin flip over two labels. Repeat it and the histogram converges to the curve it came from.

x ~ P(x) = ∫ W(x,p) dp
02

Field notes

Why this cat, and why 2023.

A cat dissolving into particles
Subject
SchrödingerStatus
Unresolved
I tried liking our cat, but the feeling wasn't reciprocated. Not even slightly. One day she disappeared. To this day, we don't know if our cat (Schrödinger), is alive or dead. Elon Musk · 17 Sep 2023 · x.com

A cat named Schrödinger walked off and never resolved. It is the only Schrödinger's cat anyone has had to actually live with — an unresolved state with a name, a food bowl, and a household that stopped waiting.

  • 1935Schrödinger publishes the cat — as an argument against taking superposition literally.
  • 1996Monroe, Meekhof, King & Wineland build the first real cat state from a single trapped ion.
  • 2018"We have a big dog called Gatsby, a little dog called Marvin the Martian & a cat named Schrödinger."
  • 2023She disappears. State unresolved.
  • 2026Oxford builds cat states whose components are themselves non-classical. Sixfold symmetry, Wigner negativity confirmed.
03

Methodology

What is computed and what is drawn. The line between them is the whole point.

Computed from the state

  • Wigner function — 96×96 grid (72² on phones), closed-form coherent-state overlaps, cross terms kept.
  • Negativity, purity, fidelity — numerical integrals over that grid. A two-component cat returns 0.3175; the textbook value is 1/π = 0.318.
  • Photon statistics — ⟨n⟩, parity and P(n) from the Fock amplitudes.
  • Decoherence — coherences damped by the photon-loss form, so distant branches lose their fringes first.
  • Observation — a Born-rule sample from P(x), logged and histogrammed.

Illustrative

  • The cat — a generated 3D mesh rendered as a hologram: wireframe, Fresnel shell, particles sampled from its surface.
  • Its copies — placed by the same α, φ, N and κ that drive the physics, but they are a picture of the state, not the state.
  • Breathing, head and tail motion — procedural. The model has no rig.
  • The chamber and these backdrops — grids, scan plane, rings and generated imagery are scene dressing.
The paper

Generating Arbitrary Superpositions of Nonclassical Quantum Harmonic Oscillator States

S. Saner, O. Băzăvan, D. J. Webb, G. Araneda, D. M. Lucas, C. J. Ballance, R. Srinivas — Phys. Rev. X 16, 021049 (2026). A single trapped strontium ion, a mid-circuit measurement, and a superposition sculpted into a shape nobody had made before. “This approach gave us a tool to sculpt the quantum superposition into almost any shape.”

Study logRead it

Open the box.

Sculpt the state, watch the fringes, and decide when to look. Or take one measurement right here — a real sample from the distribution above.

Single measurement
Nothing has been observed yet
The state is coherent. Looking will end that.
Every result is drawn from P(x) = ∫W dp
Enter the chamber Source on GitHub