Let A be a commutative algebraic group over a field K, and let G be a finitely generated subgroup of the K-rational points of A. The purpose of this thesis is to study the degrees of the Kummer extensions relative to A,K and G.

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.

Predicting the collective behaviour of systems, like a large group of people electing one of the parties, is no easy task. But there’s a theory that scientists have been using for decades to do just that: the theory of Gibbs measures. Last week, mathematician Mirmukhsin Makhmudov earned his PhD for…

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.

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

This article presents two related arguments. First, the limits of doctrinal analysis cut deeper than many EU lawyers realise. Most would probably accept that legal doctrine does not determine every legal dispute, but lawyers studying EU institutional balance often still assume that it can be deduced…

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

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…

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.

The aromatic infrared bands (AIBs) seen throughout the interstellar medium (ISM) are generally thought to be carried by polycyclic aromatic hydrocarbons (PAHs) and their nitrogen analogues (PANHs).

À La Découverte de la Hollande dans les années 1760-1770 : Pierre Famin, Emmanuel de Croÿ-Solre, François-César Le Tellier, Jean-Marie Roland de la Platière, Gabriel-François Coyer. Textes réunis et présentés par Madeleine van Strien-Chardonneau, Paris, Société française d’étude du dix-huitième siècle,…

Mass, time, space, and complexity — physicists in Leiden are launching eight new research projects tackling some of the most fundamental themes in quantum mechanics. Their goal: to push the limits of current quantum theories.

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).

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.

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…

Knowledge and culture subproject 3:

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.

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…

‘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.

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

Promotor: P. Stevenhagen, Co-promotor: R.M. van Luijk

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…

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,…

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.

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.

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

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

This dissertation provides a formal description of the relationship between diatopic/diachronic micro-variation and phonologization through analysis of the phonetic/phonological properties of unstressed vowel reduction and vowel insertion in two Northern Italian dialects.

Promotor: Prof.dr. P. Stevenhagen, Jan-Hendrik Evertse, Co-promotor: Pascal Autissier

Exploring the application of game-theoretic frameworks to quantum physics, this study creates novel AI training methods for the precise control of quantum systems.

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 dissertation shows that dialogical logic constitutes a powerful and flexible general framework for the development and study of various logical formalisms and combinations thereof.

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.

This dissertation provides crucial but as yet missing empirical data on the tone accent opposition in the so-called

Organic molecules in interstellar space are important as they influence the structure of galaxies and star formations. Studying catalytic processes in space allows us to understand how molecular species are formed and chemically evolved in the interstellar medium and solar system objects.

Promotor: W.Th.F. den Hollander Co-Promotor: F.M. Spieksma

How can innovation help or hinder public procurement processes?