This repository contains the official implementation for the paper:
Machine Unlearning in the Era of Quantum Machine Learning: An Empirical Study
We present the first comprehensive empirical study of machine unlearning (MU) in hybrid quantum-classical neural networks. While MU has been extensively explored in classical deep learning, its behavior within variational quantum circuits (VQCs) and quantum-augmented architectures remains largely unexplored.
In this work, we:
- Adapt a broad suite of machine unlearning methods to quantum settings, including:
- gradient-based methods
- distillation-based methods
- regularization-based methods
- certified unlearning techniques
- Propose two novel unlearning strategies specifically tailored for hybrid quantum–classical models.
- Evaluate unlearning under both subset removal and full-class deletion scenarios.
Experiments are conducted on Iris, MNIST, and Fashion-MNIST datasets using hybrid quantum-classical neural networks. Results show that quantum models can support effective unlearning, but outcomes depend strongly on:
- circuit depth
- entanglement structure
- task complexity
Shallow VQCs exhibit high intrinsic stability with limited memorization, while deeper hybrid models reveal stronger trade-offs between utility, forgetting strength, and alignment with oracle retraining. Across settings, methods such as EU-k, LCA, and Certified Unlearning provide the most consistent balance across metrics.
This repository is intended to serve as a baseline and benchmark for future research in quantum machine unlearning.