- 2
Numbers are expectation values. Each counts the mines expected in the 8 neighbouring cells: ⟨n⟩ = Σ P(mine)·phase.
- ½
Superposed mine (|10⟩+|01⟩)/√2: one mine spread over two nearby cells, so it adds ½ to the numbers around each. A ½ in a number means a superposition is next to it.
- 〰
Entangled pair (|00⟩+|11⟩)/√2: two cells a short distance apart that are both mines or both safe. Reveal one safely and its partner opens too (spooky action).
- −
Anti-mine with phase |−⟩: it explodes all the same but counts −1. A shown 0 means the mines around cancel out. Only a blank cell is truly empty.
- 👁
Measure collapses a cell's superposition without revealing it. The numbers around it become whole again, so you can deduce as usual. Measuring a classical cell uses up the measurement.
- ⛏
Revealing an unmeasured quantum cell measures it the hard way: a 50/50 gamble.
- ✓
To win, reveal every safe cell. Every superposition must have collapsed by then.