🦊 FOCS 2026 Workshop:
Validating quantum devices: from practice to theory
⏰ Date:
How can we characterize the behavior of a quantum device, or validate that it is performing according to specifications? This basic question is subtle for several reasons special to the quantum world: measurements of quantum systems only yield partial information and are generally destructive; full tomographic procedures require resources that grow exponentially with system size; and natural information-theoretically optimal protocols may rely on operations that cannot yet be implemented reliably in the laboratory. The challenge, therefore, is not only to design validation protocols with rigorous guarantees, but to make those guarantees compatible with experimental constraints.
The goal of this workshop is to bring the experimental priorities behind the certification and validation of quantum devices in conversation with recent progress on the theory side. The main theme will be the design of provably sound protocols under experimentally meaningful restrictions, such as local measurements, limited coherent control, imperfect state preparation and measurement, or access to only small parts of many-body systems. These topics are not only of practical relevance, but also give rise to deep theoretical questions with connections to many areas of interest to the wider FOCS community, including quantum information theory, property testing, learning theory, analysis of Boolean functions, and representation theory. Our hope is that the workshop will provide a broad audience with an accessible entry point to these questions, as well as uncover new open problems where theory can have an immediate impact on practice.
Organizers
Program: The workshop will take place at Warren Weaver Hall, 251 Mercer Street, Room 101.
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9:00–9:30: Robin Blume-Kohout (Sandia National Laboratories)
Bridging math and practice from both ends
Abstract: A community of researchers design practical protocols for assessing as-built quantum computing hardware. A community of researchers prove theorems about certification and validation of quantum devices. The overlap of these two communities is surprisingly small. I don’t think this can be easily changed, but bridges between the communities can nucleate positive change. I will try to do so from both ends — albeit from a perspective that is openly biased toward my own community (practical). First, beginning from the practical, I will try to explain some of our problems about which things might profitably be proved. Then, beginning from the math side, I will apologetically offer some meathead suggestions for making formal work more relevant and appealing to the practical crowd.
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9:35–10:05: Joseph Slote (University of Washington)
State certification with simple measurements
Abstract: When can complicated, global measurements be replaced by simple, few-qubit measurements and classical post-processing? Motivated by quantum device benchmarking, we explore this question through the fundamental task of state certification: testing whether a lab-prepared state is close to or far from a target state. We trace developments from the seminal work of Huang–Preskill–Soleimanifar to recent progress on robust protocols, with an emphasis on open questions and directions for future work.
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10:25–10:55: Sitan Chen (Harvard University)
Learning Hamiltonians under realistic constraints
Abstract: In this talk I will overview some recent results on learning Hamiltonians from time evolution under various real-world experimental constraints. In the first part I will consider the "probe tomography" setting, where in each experiment one can only control a small local subsystem, and show that generic symmetric Hamiltonians can be learned even under this restrictive access. In the second part I will consider the "uniform rotation" setting where in each experiment one starts with the all-zeros state, applies the same rotation to every qubit, time evolves, and measures every qubit in the same basis. We show that in this setting one can learn generic 2-local Hamiltonians on any interaction graph. This talk is based on https://arxiv.org/pdf/2510.08499 https://arxiv.org/abs/2610.06709
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11:00–11:30: Robert Huang (Oratomic and Caltech)
What Quantum Certification Enables
Abstract: In this talk, I will discuss how the mathematical tools of quantum state certification enable applications in sensing, learning, and optimization. I will focus on a recently discovered connection to metrology, where certification techniques yield near-optimal sensing protocols using only simple measurements. I will also cover applications to Hamiltonian learning and training neural quantum states and quantum circuits, and explore opportunities for further algorithmic connections.