We show that Kirchhoff ’s law of conservation holds for non-commutative graph flows if and only if the graph is planar. We generalize the theory of (Euclidean) lattices to infinite dimension and consider the ring of algebraic integers as such a lattice.

As of 1 June, Serge Fehr has been appointed as Professor Quantum information theory at the Leiden Mathematical Institute (MI). Fehr is employed by Centrum Wiskunde & Informatica (CWI) and as of his appointment works one day a week at the MI. Fehr’s research is focused on quantum cryptology and will…

On 12 May, GTGC Deputy Coordinator Valentina Carraro presented her work during the symposium “EU Crises: Rethinking European integration theories” at Maastricht University. The symposium was organised as part of the farewell event for the retirement of Prof. Tannelie Blom.

Ice, the solid state of water, plays an important role on our planet as well as the entire universe.Despite the fact that an individual water molecule has a very simple structure, its chemical bonding in the solid phase can be surprisingly complex.

Measurements on a superconducting material show an abrupt transition between a normal metal and a 'strange' metal. The really strange thing, however, is that this abruptness disappears when the temperature falls. 'We don't have any theoretical machinery for this', says theoretical physicist Jan Zaanen,…

This thesis studies the geometry of representation varieties and character stacks. These are spaces parametrizing the representations of a finitely generated group, typically the fundamental group of a compact manifold, into an algebraic group G.

Promotor: W.Th.F. den Hollander, Co-promotor: F.R. Nardi

Leiden students often prefer complicated theory and a difficult test to experiments. Yet associate professor Paul Logman believes students learn a lot from practical teaching. He challenges his students to come up with their research questions themselves. The Leiden Institute of Physics (LION) is at…

This thesis consists of three chapters, the first two of which concern division points of elements of the multiplicative group of a number field.

In this thesis, classes of strongly interacting quantum field theories, have been studied.

This thesis consists of three chapters. Each chapter is on a different subject. However, all three chapters address issues that arise in counting arithmetically interesting objects.

In September 2021, ACPA PhD Candidate Gabriel Paiuk will premiere a new work titled Sound Theory (The Clouds) as part of the 2021 Gaudeamus Muziekweek Festival. The performance will take place on September 10th, 20:30 at the De Helling (Utrecht, NL).

Conspiracy theories are of all times, and the government should never dismiss them as a fantasy of fools. Certainly not now, when it turned out that authorities made a conspiracy themselves with a journalist threatened with murder. Which proves that the truth is always more insane than you could have…

Dividing Worlds: Tsunamis, Seawalls, and Ontological Politics in Northeast Japan

DNA carries various forms of information. Out of these forms of information the most well-known is classical genetic information.

When professor Frank Israel graduated at Leiden Observatory some forty years ago, little did he know that one of his theories would be making headlines in 2018 - in the form of a 3D animation on the Internet, no less.

Leiden Professor of Number Theory Manjul Bhargava has been awarded a Fields Medal, widely regarded as the Nobel Prize for Maths. Bhargava is a professor in Princeton, and since 2010 has also been the holder of the Stieltjes chair in Leiden.

On Tuesday 15 September 2015, Bart de Smit has been appointed as professor of Algebra and Number Theory at the Mathematical Institute of Leiden University.

‘I got into Nature last year, I was nominated for a faculty teaching award and my kids don’t care. But if your simulations get on The Big Bang Theory then that’s something!’ says Huib van Langevelde.

As of 1 June, Floske Spieksma has been appointed Professor at the Mathematical Institute in Leiden. Her field of study is Stochastic Decision-Making. Within this field, researchers develop mathematical techniques to analyse and improve processes within organisations. ‘As a professor, I hope to safeguard…

LCD screens use liquid crystals which have a high degree of order, even though they form a fluid. A new theory maps out the interplay between order, temperature and symmetry. Publication in Physical Review X.

CFP: Two-day PhD/ Research MA masterclass Feminist Theory with and around the work of Prof. dr. Lynne Huffer organised by the OZSW in cooperation with NOG

Estudio arqueológico de la primera ciudad española en la Tierra Firme de América: Santa María de la Antigua del Darién

Climate change is made up, the secret services murdered Pim Fortuyn and JFK, and the moon landing was a fake show. Conspiracy theories are of all times, providing sensation and entertainment, but also unrest and fear. The corona pandemic is new fuel for conspiracy theorists who set fire to 5G masts,…

This thesis explores Breaking of Ensemble Equivalence (BEE) in random graph models by examining the spectral properties of adjacency matrices. The goal is to identify spectral characteristics that differentiate random graph ensembles, enhancing the understanding of complex network structures and beh…

What can Robotics and AI bring to archaeological theory and practice? In return, how can archaeology contribute to the developments in robotics and AI research? Colleagues tackled these questions at an event organised by the Faculty of Archaeology and sponsored by SAILS.

Following a special donation, the Stichting Pro Juventute foundation is facilitating a new special chair in Educational Theory and Law. Through the chair, Pro Juventute hopes to realise optimum child protection from a coherent legal and educational perspective.

In this article, Jasmijn Boeken, explores in which ways the defining characteristics of the different zones can be found in the digital sphere.

The starting point for this research project is the notion that the human brain is susceptible to all kinds of fallacies and biases that affect our perceptions and influence our reasoning outside of our conscious awareness. Indeed, most people think they are merely observing facts and that they process…

Below you will find a collection of books, other than those in the BLRN book series, to which members of BLRN have contributed.

Ten years after its introduction, the controversial idea of Erik Verlinde on gravity is still a hotly debated topic, and is still surrounded by a cloud of scepticism. Scepticism in which the media have played a major role, theoretical physicst Koenraad Schalm says in an article by NWO. ‘The media simply…

What is the origin of educational ideas, e.g., the idea that intervention in infancy has long-lasting effects on development.

The goal of this book is to place architectural studies, in which people’s interactions with each other and material resources are key, at the crossing of both landscape studies and material culture studies, where it belongs.

Among Leiden’s Firsts was Hajjah Maria Ulfah Soebadio Sastrosatomo. In 1933, she was the first Indonesian woman student to earn a law degree.

‘What I find most alluring about soil life is that you can steer it,’ researcher Martijn Bezemer of the Institute Biology Leiden (IBL) reveals. ‘You can ask: What do you want? And then I can transform the soil into something you need. At least, that is what we thought.’