← Search

Chengchang Liu

9 accepted papers

2026

Second-Order Bilevel Optimization with Accelerated Convergence Rates

ICML 2026poster

This paper studies second-order methods for nonconvex-strongly-convex bilevel optimization. We propose a novel fully second-order bilevel approximation method (FSBA) that achieves an iteration complexity of $\tilde{\mathcal{O}}(\epsilon^{-1.5})$ for finding the $(\epsilon, \mathcal{O}(\sqrt{\epsilon…

Cited by 0Source ↗Scholar ↗
2025

Quantum Speedups for Minimax Optimization and Beyond

NeurIPS 2025poster

This paper investigates convex-concave minimax optimization problems where only the function value access is allowed. We introduce a class of Hessian-aware quantum zeroth-order methods that can find the $\epsilon$-saddle point within $\tilde{\mathcal{O}}(d^{2/3}\epsilon^{-2/3})$ function value oracl…

Cited by 1Source ↗Scholar ↗
2024

Communication Efficient Distributed Newton Method over Unreliable Networks

AAAI 2024technical

Distributed optimization in resource constrained devices demands both communication efficiency and fast convergence rates. Newton-type methods are getting preferable due to their superior convergence rates compared to the first-order methods. In this paper, we study a new problem in regard to the se…

Cited by 3Source ↗PDF ↗Scholar ↗
2024

Quantum Algorithm for Online Exp-concave Optimization

ICML 2024poster

We explore whether quantum advantages can be found for the zeroth-order feedback online exp-concave optimization problem, which is also known as bandit exp-concave optimization with multi-point feedback. We present quantum online quasi-Newton methods to tackle the problem and show that there exists…

Cited by 5Source ↗PDF ↗Scholar ↗
2024

Quantum Algorithms for Non-smooth Non-convex Optimization

NeurIPS 2024poster

This paper considers the problem for finding the $(\delta,\epsilon)$-Goldstein stationary point of Lipschitz continuous objective, which is a rich function class to cover a great number of important applications. We construct a novel zeroth-order quantum estimator for the gradient of the smoothed…

Cited by 5Source ↗PDF ↗Scholar ↗