Interactive quantum mechanics tools

Every tool is free, needs no account, and works on a phone. They are built around the ideas a first course loses people on, and each one shows a number changing rather than only the rule it obeys. Together they run in order: what a state is, what measuring does to it, how to change it, and how to draw all of that as a diagram.

States and measurement

What a qubit actually is, and what happens the moment you look at one.

• First-year universitySuperposition and the Bloch sphereTwo angles, one point on a sphere. See which of them a measurement can actually detect.→
• First-year universityMeasurement and the Born ruleTurn the detector, run a thousand shots, and watch probability come out of amplitude.→

Gates and entanglement

Changing a state without measuring it, and what two qubits can do that one cannot.

• First-year universityQuantum gates and interferenceStack gates on a qubit and watch +0,5 and −0,5 cancel to nothing.→
• First-year universityEntanglement and the Bell testTurn two detectors and watch the CHSH value climb past the classical limit of 2.→

Diagrams and protocols

The picture-based approach from Picturing Quantum Processes, and the protocol it explains best.

• First-year university and upZX-calculus spidersFuse four nodes into one and watch the matrix refuse to move.→
• First-year university and upQuantum teleportation, two waysThe same protocol as a circuit and as a bent wire pulled straight.→

Lecturers, use these freely

You are welcome to project these in a lecture, put them in a problem set, or link to them from a course page. No account, no ads, nothing to install. A link back is appreciated but never required.