We start from the following famous variation of Twenty Questions Problem when one needs to find one of 106 objects by asking an oracle the minimal possible number of questions of the following type "if the given object belongs to some subset", but the oracle may sometimes lie, see [1,2]. And what if not one, but many elements should be "guessed"? A question-answer model is important here and there are many of them. These discrete problems turned out to be very close to the following continuous problem, known as compressed sensing [3,4], namely, to find an unknown sparse vector in n-dimensional Euclidean space by the minimal number of linear measurements which aren’t exact. In these lectures, we show how finite fields, via error-correcting codes, help solve these and many other problems that arise in practice.
Outline:
Lecture 1. The Renyi-Ulam game or how to find an object among a million in just 25 questions, if one answer can be wrong
Lecture 2. On various modifications of the Renyi-Ulam game
Lecture 3. Finding counterfeit coins on accurate scales with a harmful oracle
Lecture 4. Time for finite fields and error correcting codes -simplex and Hamming codes
Lecture 5. Polynomials over finite fields and Reed-Muller and BCH codes
Lecture 6. Non-overlapping convex polytopes with Boolean cube vertices and multimedia digital fingerprinting
Lecture 7. How to find sparse vector support using imprecise linear measurements
Lecture 8. Connections with Big Mathematics