Qunity: A Unified Language for Quantum and Classical Computing
Abstract
We introduce Qunity, a new quantum programming language designed to treat quantum computing as a natural generalization of classical computing. Qunity presents a unified syntax where familiar programming constructs can have both quantum and classical effects. For example, one can use sum types to implement the direct sum of linear operators, exception-handling syntax to implement projective measurements, and aliasing to induce entanglement. Further, Qunity takes advantage of the overlooked BQP subroutine theorem, allowing one to construct reversible subroutines from irreversible quantum algorithms through the uncomputation of "garbage" outputs. Unlike existing languages that enable quantum aspects with separate add-ons (like a classical language with quantum gates bolted on), Qunity provides a unified syntax and a novel denotational semantics that guarantees that programs are quantum mechanically valid. We present Qunity's syntax, type system, and denotational semantics, showing how it can cleanly express several quantum algorithms. We also detail how Qunity can be compiled into a low-level qubit circuit language like OpenQASM, proving the realizability of our design.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 09, 2023
- Source ID
- 10.1145/3571225
Entities
People
- Finn Voichick
- Liyi Li
- Michael Hicks
- Robert Rand
Organizations
- Air Force Office of Scientific Research
- National Science Foundation
- Office of Advanced Scientific Computing Research
- University of Chicago
- University of Maryland