Department of Mathematics and Computer Science

Speaker: Frederik Nathan (University of Copenhagen).Abstract: The current main paradigm for quantum computing — active quantum error correction (AEC) with overhead qubits — faces two challenges: Realizing long-lived logical qubits at reasonable resource cost, and achieving universal fault-tolerant quantum gates. At the root of these challenges lie two no-go theorems: The Braviy-Terhal theorems, which forbids passively-stabilized, or self-correcting, qubits in <4 dimensions, and the Eastin-Knill theorem which dictates that fault-tolerant non-Clifford gates must be generated with costly magic distillation or cultivation routines. Together, these theorems imply that even simple quantum information processing operations require continuous readout, data processing, and feedback control of very large numbers of overhead qubits. Here I illustrate how the no-go-theorems above are not as far-reaching as one could fear, but can be circumvented via an alternative paradigm for quantum computing currently gaining experimental maturity: bosonic codes (BC), which redundantly encodes a qubit in the infinite-dimensional Fock state of a single continuous variable. In particular, I will demonstrate how tuning the impedance of a simple driven-dissipative superconducting resonator to a “magic” value given by a constant of nature can lead to a self-correcting Gottesman-Kitaev-Preskill qubit that supports exponentially-robust Clifford and non-Clifford gates [1,2]. [1] FN, L. O’Brien, K. Noh, M.H. Matheny, A.L. Grimsmo, L. Jiang, G. RefaelPRX Quantum 6 (3), 030352 (2025)[2] L. O'Brien, G. Refael, FN arXiv:2507.19713 (2025)

How do universities build a strong ERC (European Research Culture) culture - and why is it important?

Speaker: Ralph Kaufmann (Purdue University).Abstract: Quantum phase transitions are a key part of the quantum landscape. These appear in mathematical systems and real materials. They are potentially useful for quantum computing and quantum sensing. In joint work with Mohamad Mousa and Birgit Kaufmann-Wehefritz, we showed that any abstract phase diagram of Chern insulators can be achieved in a continuum model. Furthermore, we gave sequences of higher Chern models built on tight-binding models exhibiting an infinite sequence of Chern numbers. In newer developments these constructions also will shed light on MPS and materials with symmetries. We also conjecture that they will be useful for quantum error correction.

Speaker: Birgit Kaufmann (Purdue University).Abstract: Quantum annealers represent an interesting approach to quantum computing, which make use of the adiabatic theorem to efficiently find the ground state of a physically realizable Hamiltonian. Such devices are currently commercially available and have been most successfully applied to several combinatorial and discrete optimization problems. However, the application of quantum annealers to problems in chemistry remains a relatively sparse area of research due to the difficulty in mapping molecular systems to the Ising Hamiltonian representing the architecture of the DWave quantum computer. In this talk, we review two different methods for finding the ground state of molecular Hamiltonians using Ising-model-based quantum annealers. In addition, we compare the relative effectiveness of each method by calculating the binding energies, bond lengths, and bond angles of the H3+ and H2O molecules and mapping their potential energy curves. We also assess the resource requirements of each method by determining the number of qubits and computation time required to simulate each molecule using various parameter values. While each of these methods is capable of accurately predicting the ground state properties of small molecules, we find that they are still outperformed by modern classical algorithms and that the scaling of the resource requirements remains a challenge.

With Einstein's theory of general relativity as our onset, we will in this talk explore the two most dramatic chapters in cosmic history: the birth of the Universe and its possible ultimate fate. We will look at what modern cosmology reveals about the earliest moments after the Big Bang, and discuss the leading scenarios for how the Universe may evolve in the far future.Come joins us with your peers for an interesting talk from Sofie Marie Koksbang, Associate Professor of Cosmology at CP3 Origins. She was recieved the Research Communication Award, because she time and time again draws the cosmos close to her audience and turns the vast universe into fascinating stories.The event is held at the IMADA Forskertorv.You can read more in the Facebook group IMADA-students.

Speaker: Boris Kjær (​University of Copenhagen)Abstract:TBA

Maiken Westen Holm Svendsen defends her PhD thesis at a public lecture: “Mod en mere sammenhængende evalueringskultur i matematikfaget på HTX – STEM-forløb mellem læring, kompetence og viden”.The chairman of the assessment committee, Associate Professor Gitte Miller Balslev, will act as chairman at the defence.The PhD defence takes place in IMADA Conference Room (Ø18-509-2).All are welcome.

The Cake Club is a new and cozy initiative that meets four times each semester with free coffee, cake, and great company.So whether you study AI, Applied Mathematics, Computer Science, Mathematics, or Mathematics-Economics, you are invited.Remember to bring your fellow students (lecturers are also welcome).The club meetings are held at the IMADA Forskertorv.You can read more in the Facebook group IMADA-students.

Speaker: Sara Maggio (​University of Bonn)Abstract: TBA

The Cake Club is a new and cozy initiative that meets four times each semester with free coffee, cake, and great company.So if you study Data Science, you are invited.Remember to bring your fellow students (lecturers are also welcome).The club meetings are held at the IMADA Forskertorv.You can read more in the Facebook group IMADA-students.

In this event we will look at how teaching can help spark students’ individual learning awareness and build engagement to help foster a strong learning community between our students.

In this event we will look at how teaching can help spark students’ individual learning awareness and build engagement to help foster a strong learning community between our students.

The Cake Club is a new and cozy initiative that meets four times each semester with free coffee, cake, and great company.So whether you study AI, Applied Mathematics, Computer Science, Mathematics, or Mathematics-Economics, you are invited.Remember to bring your fellow students (lecturers are also welcome).The club meetings are held at the IMADA Forskertorv.You can read more in the Facebook group IMADA-students.

The Cake Club is a new and cozy initiative that meets four times each semester with free coffee, cake, and great company.So if you study Data Science, you are invited.Remember to bring your fellow students (lecturers are also welcome).The club meetings are held at the IMADA Forskertorv.You can read more in the Facebook group IMADA-students.

SDU and NAFA invite you to a webinar where PhD Sizwe Nxasana presents his research on how to support teachers in unlearning old habits and adopting new, more student-centered teaching methods – and on identifying which forms of professional development actually work to make this happen. This presentation offers a unique insight into how project-based learning (PBL) is being adopted and developed in a South African context.At NiSE webinars, Danish science education researchers meet to further develop the science education knowledge ecology.It is about ensuring that everyone both receives knowledge and contributes knowledge and experiences within the pedagogical and scientific work of science education.The NiSE webinars are organized by the STEM Education Research Center – FNUG and the Center of Excellence in Science Education/Naturfagsakademiet (CESE/NAFA). NiSE is the name of the network: Network in STEM Education.This webinar is the second in a series of three during the autumn semester of 2025.Everyone is welcome.