009 Interference Maze
SimulatorSteer a coin through splitters by flipping the sign of a path. Paths with the same sign add, opposite signs cancel.
Simulator running in your browser. Real hardware: coming soon (planned provider: IBM Quantum).
What's happening?
A puzzle game about quantum interference: switch on Shift the spin to make paths cancel or add, and steer a simulated coin to Heads or Tails through a maze of splitters. Simulator only.
You will learn: Interference: how amplitudes with signs add and cancel.
The circuit
Each splitter is a Spin the coin step (the Hadamard gate). Each switch is an optional Shift the spin step (the Z gate), which leaves the Heads path alone and flips the sign of the Tails path. The whole maze is the circuit H, (Z), H, (Z), H, ... on one qubit. The two lines in the picture are the two ways the coin can be, Heads and Tails. This is a teaching picture: the coin is not secretly taking one line.
What you are seeing
Bright dots are likely paths. Cyan means a positive sign and pink means a negative sign. At each splitter a path splits into two, and the new Heads or Tails amplitude is the sum of two contributions. If the two contributions have the same sign they grow, and if they have opposite signs they cancel to nothing. With only splitters and shifts the coin always ends as a sure Heads or a sure Tails when there is an even number of splitters, which makes the puzzles solvable. Read Quantum Interference Explained With Three Gates for the arithmetic of the two splitter case.
Honest notes
- It is not a model of light in a real interferometer, although the maths is the same kind. Real devices need careful alignment.
- Looking at the coin between splitters picks one path, so the later cancelling would not happen. The Lab does not allow looking mid-maze for that reason.
Run on real hardware: coming soon. The planned provider is IBM Quantum. It is not connected yet. Every result on this page comes from a simulator running in your browser, not from a quantum computer.
How it works: the simulator keeps the exact quantum state of the qubits as a list of complex numbers, applies each gate to it, and draws random samples from the resulting probabilities. The random numbers are ordinary pseudo random numbers from your browser, and a real device would add noise. No QNT, wallet or account is needed.
Sources
This is an educational simulator, not financial advice. QUANTUM (QNT) is an independent community token on Solana and does not perform quantum computation.