Section 1 of 7

Basic Concepts

A shuffle can scramble positions while leaving a count untouched.

The course opens with Miraskill, a trick in which a deck the spectator shuffles still keeps a promise. The two lectures that follow set up the language for everything after: what a shuffle does to positions, identities and faces, and how to ask what cannot change.

Lectures
01–03
Running time
About one hour
Formats
One performance, two mathematics lectures

Lectures in this section

Performance lecture, with a trick to play Mathematics lecture

  1. Lecture 1, performance: Miraskill: order hidden inside a shuffled deck

    Deal a shuffled deck in pairs. The red–red pile and the black–black pile always tie.
    Play Miraskill
  2. Lecture 2, mathematics: What a shuffle actually does

    Distinguish identity, position and orientation, and compute cuts, reversals, deals, riffles and compositions on a labeled packet.
  3. Lecture 3, mathematics: The magician’s question: what cannot change?

    Formulate an invariant with an initial condition and legal moves, and distinguish proof, testing and counterexamples.