logicalguess

The book is in MEAP at Manning: https://www.manning.com/books/building-quantum-software, with 5 chapters available right now. I want to spread the elementary approach, I didn't want the post to look like pushing for the book. There is also an additional repository (https://github.com/learnqc/code_plus) that has interactive UIs and an assistant (work in progress).

An implementation of a basic quantum computing simulator with a minimal introduction for developers. You can think of the introduction as a requirements document for the implementation, with no complex mathematical notation, or unnecessary high-level algebra. Developers who understand complex numbers, binary strings and some probabilities should feel at home.

An expanded version of the code is available here: https://github.com/learnqc/code/tree/main/src/hume. The introduction is also expanded in the first chapters of a book, but this write-up is supposed to be standalone and help developers understand what quantum computing is. It's simpler than most people think.

For those who are interested, there is a strong connection between FFT and quantum gates. Applying a gate to a target qubit in a quantum system follows the same computing pattern as one stage in FFT. Consequently, any quantum simulator contains an FFT implementation, and an efficient FFT implementation can be ported to a quantum simulator implementation.

To see how quantum gates work, take a look at Spinoza: https://github.com/QuState/spinoza, a sister project for PhastFT, and Hume, a simpler, but lower performing, Python version: https://github.com/learnqc/code/tree/main/src/hume.