When Quantum Makes You Drunk

Published by César A. Rodríguez Rosario (03/17/2021)

Quantum Walks are a great way to get a feel for the power of quantum computing. They aren't too different from the (classical) random walk, where a drunk can randomly decide to go left or right.

Galton Board for the Classical Random Walk

However, in the case of the quantum drunk, it can go into a superposition of both left and right.

Quantum drunk goes into superpositions.

This leads to very different behavior, and even makes the quantum drunk better at some tasks than the classical drunk could ever be.

In this project, we show you the core steps for a quantum walk on a 4-node graph on the following network. 

Play with the code, see if you can:

  • Change the number steps to 2, 3, maybe 4, then 5... do you notice any patterns?
  • Can you change the initial state? How does it affect the walk?
  • Can you change how the coin is prepared? How does this affect the way the drunk stumbles?