Continuous optimization is never easy: the exact solution is always a luxury demand and the theory of it is not always analytical and elegant.

In this book Adam Fairclough chronicles the odyssey of black teachers in the South from emancipation in 1865 to integration one hundred years later.

Multiple stars, that is two or more stars composing a gravitationally bound system, are common in the universe.

The high velocity tail of the total velocity distribution of stars provides essential insight into fundamental properties of the Galaxy.

The Jeugdwerkgroep is a national astronomy association for young people who are interested in astronomy. The Leiden section organizes a monthly meeting in the Old Observatory Leiden.

Promotor: W. Jaffe, Co-promotor: K. Meisenheimer

The radio sky harbours both galactic and extragalactic sources of arcminute- to degree-scale emission of various physical origins. To discover extragalactic diffuse emission in the Cosmic Web beyond galaxy clusters, one must image low–surface brightness structures amidst a sea of brighter compact fore-…

Following the Big Bang, structure in the Universe started collapsing under the force of gravity. This resulted in the formation of the first stars, galaxies and clusters of galaxies.

Thermodynamics is one of the founding scientific pillars that has helped us better understand heat engines, biology, ecosystems, and even black holes. While it fundamentally describes large systems by examining the bulk behavior of their constituents, it is anchored in the statistical equivalence of…

Kaveh Lahabi's lab explores the exotic physics of quantum materials, whose underlying physics seems to have more in common with elementary particles and black holes, than ordinary metals and semiconductors.

Promotor: Prof.dr. J. Zaanen, A. Parnachev

This is the physics summer school of Leiden University. It is part of the Leiden Institute of Physics (LION). The summer school is intended for Bachelor (BSc) students in physics. It covers topics from quantum matter and optics, to biological & soft matter physics and cosmology and theoretical physics.…

Optimization tasks in practice have multifaceted challenges as they are often black box, subject to multiple equality and inequality constraints and expensive to evaluate.

In White Lies and Black Markets, Fatah-Black offers a new account of the colonization of Suriname—one of the major European plantation colonies on the Guiana Coast—in the period between 1650-1800.

How is Indian foreign policy made? This special issue of the journal India Review, edited by political scientists Nicolas Blarel (Leiden University) and Avinash Paliwal (SOAS University of London) features a number of interesting case studies that bridge the gap between Foreign Policy Analysis and India’s…

The thesis addresses the long-term dynamical evolution of hierarchical multiple systems.

Cultural Anthropology and Development Sociology at Leiden University studies the everyday practices of individuals and groups around the world in relation to the complex global challenges of diversity, sustainability, and digitalisation.

An Introduction and Field Guide, Second and Revised Edition (15 December 2014)

In the spirit of 'unity in diversity', our objective is to promote insight into and appreciation for the wonder that the same physical laws and mathematical concepts apply to the whole of nature, from the largest to the smallest energy and length scales. We strive for the application of abstract theoretical…

We explore the particle physics and quantum world at the time of the big bang.

During the bachelor’s programme Astronomy you will immerse yourself in questions about our universe. Questions such as: ‘what happens in a black hole?’ and ‘what is dark matter?’ In doing so you will learn to apply mathematics and physics to astronomical problems and you will work with computer simulations…

Uncertainty and noise are frequently-encountered obstacles in real-world applications of numerical optimization. The practice of optimization that deals with uncertainties and noise is commonly referred to as robust optimization.

This book is the first systematic analysis of the changes in the use of goods and services by households of Black South Africans since the early nineteenth century.

In their quest for materials that conduct electricity without resistance at moderate temperatures, scientists usually work on their chemical make-up. Now Leiden physicists have come up with a radically new approach: pinching holes in a periodic pattern. Publication in SciPost.

Leiden University's Citizen Science Lab supports and organizes initiatives where anyone can get started with scientific data and research. This is how we enrich research with insights from the community, make science accessible to all, and tackle important local issues together.

The design for the METIS instrument for the Extremely Large Telescope (ELT) is final. The European Southern Observatory (ESO) has given the green light for production of all parts of the instrument. It is the first ELT instrument, designed and to be built under Dutch leadership, to formally pass the…

The aim of the project is to contribute to the process of archive formation ongoing in Post-Apartheid South Africa through the inclusion of photographs that have been either unacknowledged or excised from the national canon.

If three or more objects move around each other, history cannot be reversed. That is the conclusion of an international team of researchers based on computer simulations of three black holes orbiting each other. The researchers, led by the Dutch astronomer Tjarda Boekholt, publish their findings in…

On 3 December the Europa Institute organised a debate about the figure of Black Pete. The central theme of the debate was the role which the law can play in deciding the future of Black Pete.

Anthropologist Rodrigo Ochigame studies how AI is changing the practice of scientific research. From astrophysics to mathematics to climate science, they find that the adoption of new AI models is raising questions about what counts as reliable scientific evidence.

On November 21, theoretical physicist Juan Maldacena gives the Ehrenfest Colloquium. Maldacena is known worldwide as the inventor of AdS/CFT correspondence, which might be key to a theory of quantum gravity. Maldacena is winner of the prestigious Dirac Prize and the Breakthrough Prize in Fundamental…

Rottgering

The Old Obervatory Leiden is one of the partners of the local learning ecosystem ‘Verwonder om de Hoek’, an educational platform from Leiden that lets school children and families wonder about the world of Nature, Science, Technology and Sustainability. On this page you will find the educational programmes…

Simulations of galaxies help researchers understand astronomical observations better. The EAGLE simulation, a large project in which Leiden astronomers play a leading role, shows the evolution of the Universe, from just after the Big Bang to the present day.

On this page you will find an overview of awards and prizes granted to our staff and students in 2024, as well as special appointments at Leiden University and other institutions.

The centre of our Galaxy is so dark and dense that it is almost impossible to observe what is inside. By catching the rare hypervelocity stars that are ejected from it, Elena Maria Rossi aims to unveil the mysterious environment around the supermassive black hole inside. But she’ll also be solving another…

All kinds of reasons have been put forward for why plants apparently fail to make maximum use of the available light. None of these reasons can explain why after two billion years of evolution they are not black, like industrial photovoltaic solar cells. Are we missing something?

Older children more frequently link Black Pete with a black person. Both younger and older children think positively about him. This is the conclusion of a study conducted by Judi Mesman, Professor of Diversity in Parenting and Development.

Media all around the world reported about it: the most detailed images yet seen of galaxies, shot by radio telescope LOFAR. The international team behind these amazing results were led by Leah Morabito at Durham University and included three talented Leiden astronomers.

Theoretical physicists Kevin Grosvenor and Sam Young have won Marie Curie grants for research projects at LION/Lorentz Institute.

By a stroke of luck, a team led by Dutch PhD student Martijn Oei has discovered a radio galaxy of at least 16 million lightyears long. The pair of plasma plumes is the largest structure made by a galaxy known thus far. The finding disproves some long-kept hypotheses about the growth of radio galaxie…

The ability to collect and interpret huge quantities of data has become indispensable to society and academia. Leiden University is a knowledge and expertise centre for data science that places the emphasis on interdisciplinary collaboration and innovation.

Astronomers want to understand the Universe, from the Big Bang to the present day, and what the future will hold. In Leiden they focus on two key questions: ‘How did stars and planets originate’ and ‘How were galaxies and black holes formed in the young Universe?’ A new generation of telescopes – just…

Astronomers from Leiden Observatory have developed a new method to find distant quasars and better distinguish them from other objects that look like them, using machine learning techniques. The research result has been accepted for publication in the journal Astronomy & Astrophysics. It is the last…

Over a seven year period an international team of scientists has mapped more than a quarter of the northern sky using the Low Frequency Array (LOFAR), a pan-European radio telescope. From Leiden, Astronomer Timothy Shimwell and Huub Röttgering, among others, are involved. It reveals an astonishingly…

Black Theatre, activist theatre by and for black South Africans, flourished under apartheid. However, according to Francis Rangoajane, the democratisation of South Africa has in no way diminished the importance of this art form. PhD defence 16 November.

Historian Karwan Fatah-Black researches the Dutch colonial past, and regularly joins in the public debate about this. He has been admitted to The Young Academy for his dedication to academia and society.

The worldwide protests following the police violence in the United States show how deep-rooted and wide-spread racism is across the world. As an academic institution doing research on law & society, the Van Vollenhoven Institute is very much aware of systemic racism and speaks out in support of these…