Near-Optimal Quantum Lower Bounds for Convex Optimization via Fourier Rank
- URL: http://arxiv.org/abs/2609.09035v1
- Date: Tue, 08 Sep 2026 17:01:51 GMT
- Title: Near-Optimal Quantum Lower Bounds for Convex Optimization via Fourier Rank
- Abstract summary: We show that any algorithm that, for every unit linear objective, returns an exactly feasible point with additive objective error $(n-2)$ requires $!left(fracnlog n,loglog nright)$ membership queries.<n>The same lower bound can be shown to hold if the returned point is only required to be approximately feasible, within $(n-2)$ distance from the feasible set.
- Score: 3.5601262095726987
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We establish a near-linear quantum query lower bound for high-accuracy convex optimization over an explicit family of $n$-dimensional ellipsoids. We focus on linear optimization with an explicitly given objective, where the feasible set is accessed through a membership oracle. We show that any algorithm that, for every unit linear objective, returns an exactly feasible point with additive objective error $Θ(n^{-2})$ requires $Ω\!\left(\frac{n}{\log n\,\log\log n}\right)$ membership queries. The same lower bound can be shown to hold if the returned point is only required to be approximately feasible, within $Θ(n^{-2})$ distance from the feasible set. This resolves, up to logarithmic factors, an open question posed by Chakrabarti, Childs, Li, and Wu~(\textit{Quantum}, 2020) and by van Apeldoorn, Gilyén, Gribling, and de Wolf~(\textit{Quantum}, 2020). Coupled with the upper bounds in these papers, the query complexity of high-accuracy convex optimization is characterized tightly up to logarithmic factors. The proof is built around a lower bound for determinant computation that is derived via a novel polynomial method based on Fourier-rank. In the continuous matrix phase-query model, computing the determinant of a real $n\times n$ matrix requires at least $n/2$ matrix-vector product queries. The construction also yields an $Ω(n)$ phase-query lower bound for estimating the minimum eigenvalue of a real symmetric $n\times n$ matrix to additive accuracy $Θ(n^{-2})$. These results extend the determinant and minimum-eigenvalue lower bounds of Childs, Hung, and Li~(ICALP 2021) from finite fields to the real-valued setting. Based on the same constructions, we also prove a near-optimal gradient-query lower bound for constant-accuracy optimization of smooth and strongly convex functions.
Related papers
- Quantum Speedups for Stochastic Optimization with Heavy-Tailed Noise [49.730496294398726]
We develop a novel quantum mean estimator for heavy-tailed random variables.<n>We derive stronger lower bounds for tail index>4/3$, showing that a nontrivial dependence on a dimension is unavoidable.<n>For a convex objective function, we propose a quantum projected gradient descent method.
arXiv Detail & Related papers (2026-07-28T09:29:37Z) - Hardness of High-Dimensional Linear Classification [58.29089693778071]
We establish new exponential in dimension lower bounds for the Maximum Halfspace Discrepancy problem.<n>Both are fundamental problems in computational geometry and machine learning in their exact and approximate forms.
arXiv Detail & Related papers (2026-03-19T15:53:41Z) - Quantum Algorithms for Projection-Free Sparse Convex Optimization [32.34794896079469]
For the vector domain, we propose two quantum algorithms for sparse constraints that find a $varepsilon$-optimal solution with the query complexity of $O(sqrtd/varepsilon)$.<n>For the matrix domain, we propose two quantum algorithms for nuclear norm constraints that improve the time complexity to $tildeO(rd/varepsilon2)$ and $tildeO(sqrtrd/varepsilon3)$.
arXiv Detail & Related papers (2025-07-11T12:43:58Z) - Quantum Algorithms for Non-smooth Non-convex Optimization [30.576546266390714]
This paper considers the problem for finding the $(,epsilon)$-Goldstein stationary point of Lipschitz continuous objective.
We construct a zeroth-order quantum estimator for the surrogate oracle function.
arXiv Detail & Related papers (2024-10-21T16:52:26Z) - A quantum central path algorithm for linear optimization [5.450016817940232]
We propose a novel quantum algorithm for solving linear optimization problems by quantum-mechanical simulation of the central path.
This approach yields an algorithm for solving linear optimization problems involving $m$ constraints and $n$ variables to $varepsilon$-optimality.
In the standard gate model (i.e., without access to quantum RAM), our algorithm can obtain highly-precise solutions to LO problems using at most $$mathcalO left( sqrtm + n textsfnnz (A) fracR_1
arXiv Detail & Related papers (2023-11-07T13:26:20Z) - An Algorithm with Optimal Dimension-Dependence for Zero-Order Nonsmooth Nonconvex Stochastic Optimization [37.300102993926046]
We study the complexity of producing neither smooth nor convex points of Lipschitz objectives which are possibly using only zero-order evaluations.
Our analysis is based on a simple yet powerful.
Goldstein-subdifferential set, which allows recent advancements in.
nonsmooth non optimization.
arXiv Detail & Related papers (2023-07-10T11:56:04Z) - ReSQueing Parallel and Private Stochastic Convex Optimization [59.53297063174519]
We introduce a new tool for BFG convex optimization (SCO): a Reweighted Query (ReSQue) estimator for the gradient of a function convolved with a (Gaussian) probability density.
We develop algorithms achieving state-of-the-art complexities for SCO in parallel and private settings.
arXiv Detail & Related papers (2023-01-01T18:51:29Z) - Optimal Query Complexities for Dynamic Trace Estimation [59.032228008383484]
We consider the problem of minimizing the number of matrix-vector queries needed for accurate trace estimation in the dynamic setting where our underlying matrix is changing slowly.
We provide a novel binary tree summation procedure that simultaneously estimates all $m$ traces up to $epsilon$ error with $delta$ failure probability.
Our lower bounds (1) give the first tight bounds for Hutchinson's estimator in the matrix-vector product model with Frobenius norm error even in the static setting, and (2) are the first unconditional lower bounds for dynamic trace estimation.
arXiv Detail & Related papers (2022-09-30T04:15:44Z) - Near-optimal fitting of ellipsoids to random points [68.12685213894112]
A basic problem of fitting an ellipsoid to random points has connections to low-rank matrix decompositions, independent component analysis, and principal component analysis.
We resolve this conjecture up to logarithmic factors by constructing a fitting ellipsoid for some $n = Omega(, d2/mathrmpolylog(d),)$.
Our proof demonstrates feasibility of the least squares construction of Saunderson et al. using a convenient decomposition of a certain non-standard random matrix.
arXiv Detail & Related papers (2022-08-19T18:00:34Z) - Best Policy Identification in Linear MDPs [70.57916977441262]
We investigate the problem of best identification in discounted linear Markov+Delta Decision in the fixed confidence setting under a generative model.
The lower bound as the solution of an intricate non- optimization program can be used as the starting point to devise such algorithms.
arXiv Detail & Related papers (2022-08-11T04:12:50Z) - Near-Optimal Lower Bounds For Convex Optimization For All Orders of
Smoothness [26.71898403195793]
We study the complexity of optimizing highly smooth convex functions.
For a positive integer $p$, we want to find an $epsilon$-approximate minimum of a convex function $f$.
We prove a new lower bound that matches this bound (up to log factors), and holds not only for randomized algorithms, but also for quantum algorithms.
arXiv Detail & Related papers (2021-12-02T10:51:43Z) - Finding Global Minima via Kernel Approximations [90.42048080064849]
We consider the global minimization of smooth functions based solely on function evaluations.
In this paper, we consider an approach that jointly models the function to approximate and finds a global minimum.
arXiv Detail & Related papers (2020-12-22T12:59:30Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.