Institut for Matematik og Datalogi

Speaker: ​Kasper Green Larsen (Aarhus University).Abstract: Achieving a provable exponential quantum speedup for an important machine learning task has been a central research goal since the seminal HHL quantum algorithm for solving linear systems and the subsequent quantum recommender systems algorithm by Kerenidis and Prakash. These algorithms were initially believed to be strong candidates for exponential speedups, but a lower bound ruling out similar classical improvements remained absent. In breakthrough work by Tang, it was demonstrated that this lack of progress in classical lower bounds was for good reasons. Concretely, she gave a classical counterpart of the quantum recommender systems algorithm, reducing the quantum advantage to a mere polynomial. Her approach is quite general and was named quantum-inspired classical algorithms. Since then, almost all the initially exponential quantum machine learning speedups have been reduced to polynomial via new quantum-inspired classical algorithms. From the current state-of-affairs, it is unclear whether we can hope for exponential quantum speedups for any natural machine learning task. In this work, we present the first such provable exponential separation between quantum and quantum-inspired classical algorithms. We prove the separation for the basic problem of solving a linear system when the input matrix is well-conditioned and has sparse rows and columns.

Speaker: ​Gerard Valentí-Rojas (Atom Computing).Abstract: Since Kitaev's seminal introduction of the toric code, the search for more efficient quantum error-correcting (QEC) codes has been a central challenge in the quest for fault-tolerant quantum computation. Beyond protecting quantum information from noise, practical QEC codes must also admit efficient real-time decoding and support low space-time volume implementation of logical operations.These requirements have driven the development of increasingly sophisticated code families. In this talk, I will survey a selection of CSS quantum low-density parity-check (qLDPC) codes that can be viewed as natural extensions of the toric code paradigm. By highlighting the underlying ideas that connect these constructions, I will illustrate how many seemingly complex qLDPC codes emerge from relatively simple modifications of the toric-code framework.I will also present recent experimental results obtained at Atom Computing using neutral atoms in optical-tweezer arrays and discuss current perspectives on the implementation of logical gates in these codes.

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Speaker: ​Edison Carrera (CEA).Abstract: Rydberg-atom arrays provide a programmable platform for engineering long-range interacting spin systems and generating metrologically useful entangled states. In this talk, I will present a quantum optimal-control approach for preparing spin-squeezed states in ring arrays with van der Waals Ising interactions. Starting from an initially unentangled state, gradient-based optimization is used to design tailored pulse sequences that drive the system toward strongly correlated states with a prescribed squeezing direction. Compared with the uncontrolled dynamics, the optimized protocols yield substantially enhanced spin squeezing and remain robust as the system size increases.A notable feature is that control pulses optimized on small arrays can be transferred to significantly larger systems without re-optimization, suggesting a scalable route to entangled-state preparation in programmable Rydberg platforms. I will conclude with a brief outlook on related questions of controllability and state-preparation complexity in neutral-atom systems.

The Masterclass is mainly aimed for master students, advanced bachelor students and PhD students interested in quantum computing from any related fields.

The Masterclass is mainly aimed for master students, advanced bachelor students and PhD students interested in quantum computing from any related fields.

Speaker: Raphael Senghaas (​Heidelberg University).Abstract: TBA

The Niels Bohr Quantum Summer School is a national initiative under the Danish National Quantum Strategy, bringing together Danish and international PhD students for an intensive two-week programme in quantum science and technology. This year’s edition focuses specifically on Quantum Algorithms and Quantum Software, discussing the quantum computational model, quantum algorithm design, and quantum software compilation and optimization, including the principles from quantum mathematics and computer science that underpin these topics.

SDU Sønderborg 21 August 2026 - A forum for researchers, health professionals and employees in companies to meet

SDU Sønderborg 21 August 2026 - A forum for researchers, health professionals and employees in companies to meet

Mathematics continues to shape the technologies, economies, and discoveries of tomorrow. This conference brings together leading minds to explore how applied mathematics drives innovation, connects fields, and creates real-world impact.

Mathematics continues to shape the technologies, economies, and discoveries of tomorrow. This conference brings together leading minds to explore how applied mathematics drives innovation, connects fields, and creates real-world impact.

In this presentation, I will present my methods for activating teaching, which I have implemented both in an existing course I took over from a colleague, and in a new course that I have built myself from scratch.

Et udvidet FNUG forskningsseminar med gæsteforskere.

På dette forskningsseminar præsenterer forskere og studerende fra FNUG nyt fra deres aktuelle forskning. Inden da er der frokost på sammenskudsbasis

Poster Session og oplæg