Description

Imagine your given the task to write a numerical program on your computer, maybe a simple one like summing certain numbers or a bit more difficult to integrate a function. Now you know an algorithm and you'll start implementing it. Are you writing bit-operations?

No, most certainly not! You'll use fundamental arithmetic operations like * + - / ^ or even an existing library.

But in Quantum computing frameworks we're often restricted to really using low-level qubit operations, like the Pauli gates or the Hadamard gate. This makes writing elaborate algorithms very strenuous and you might find yourself re-implementing the same bits of code again and again.

To allow writing algorithms more quickly and to enable re-use of modular code blocks, we've started a library of useful circuits: Qiskit's circuit library. In this project, you'll add important circuits for basic arithmetic operations like addition or multiplication, including some tests to validate them.

Examples:

• Ripple-carry adder: https://arxiv.org/pdf/quant-ph/0410184.pdf
• QFT-based adder: https://arxiv.org/pdf/quant-ph/0008033.pdf
• Multiplication: https://arxiv.org/pdf/1411.5949.pdf
• and others!

Mentor/s

Julien Gacon (@Cryoris), Pre-Doc researcher at IBM Research Zurich, Qiskit Terra and Aqua core developer

Type of participant

You just need basic knowledge of Python and Qiskit circuits 🙂 Ideally you're familiar with some arithmetic circuits, such as the adder circuits.

Number of participants

2

Deliverable

Depending on how fast we move along there are different levels we can reach:

Level 1:

Basic arithmetic circuits (and tests) added to the circuit library:

• Adders
• Multipliers
• (opt) Tutorial

Level 2:

• Piecewise Polynomials

Level 3:

• Inverse square root
• Arcsine

Progress is tracked here: https://github.com/Cryoris/qiskit-terra/projects/2