Not all problems are easy to solve, but with enough bright minds, you make progress step by step. ‘The kind of problems I am interested in have been occupying mathematicians for over two millennia,’ says theoretical mathematician David Lilienfeldt. In September, he started at the Mathematical Institute…

PhD defence

Organisation

Finance

In 2021 a record number of researchers obtained a PhD at Leiden University. Despite the coronavirus pandemic, the number of PhDs conferred was 448, one more than the previous record year of 2018.

Where to study ’politics’? According to the QS World University Rankings, Leiden University is a good choice. In the 2021 edition, Leiden and The Hague retain their position in the top 25 of the most esteemed institutes worldwide. Within the Netherlands, we again claim the first position.

A cap on the number of international students at the five broad-based Randstad universities will have a drastic effect on the Dutch economy. The gross domestic product (GDP) is expected to decline by approximately 4 to 5 billion euros. Regions, businesses and society as a whole will feel the consequ…

‘Microscopy is by far the least understood, most inefficiently operated, and the most abused of all laboratory instruments,’ reads the quote on the office wall of microscopy unit supporters Joost Willemse en Gerda Lamers. It describes exactly why the two developed the microscopy course for starting…

To protect sensitive data, such as personal details or confidential business information, the university uses so-called sensitivity labels in Microsoft 365. On this page, you can learn what sensitivity labels are and how to use them.

Does gravity work the same when you look at the largest scales in our universe? That’s what Leiden physicist Alessandra Silvestri will study with a 2 million euro ERC Consolidator grant. ‘We assume that it does, but we don’t actually know.’

Ten Leiden researchers have been awarded a Veni grant by the Dutch Research Council (NWO). The grant, of up to 280,000 euros, will enable them to elaborate their ideas over a period of three years.

The 50th Top 450 entry has now been published. In the run-up to the university’s 450th anniversary, we are compiling our Top 450. What is your favourite?

The number of students enrolled at Leiden University remained stable this year. As at other Dutch universities, the growth in recent years seems to have levelled off. Leiden University is also following the national trend in terms of intake at the bachelor’s and master’s levels. The number of international…

The number of books by U.S. authors released in China has drastically decreased in recent years. Assistant professor Svetlana Kharchenkova wrote an article about this for the Diplomat.

What a result! The Higher Education BioBlitz recorded 3,155 species, smashing our target of 2,500. Thanks to your efforts, Leiden University made an impressive eight ‘very rare’ finds. A result that gives hope for our biodiversity.

Explosions at people’s homes, gangland killings and online threats: if you follow the news, it may seem as though threat levels in the Netherlands are rising. But is that really true? Researchers from Leiden University investigated this and have presented their results in the Dreigingsmonitor (Threat…

As of 1 October, David Holmes has been appointed full professor of Pure Mathematics at the Mathematical Institute (MI). His work lies at the intersection of algebra, geometry and number theory.

On Tuesday 30 September 2025, PhD candidate Kathleen Brown will defend her dissertation 'Deception, Risk, and Evasion: The Politics of Sovereign Debt in Emerging Markets' in Leiden’s Academy Building. Her research sheds light on the hidden world of sovereign debt politics, revealing how governments…

Speaking with your manager more often, focusing explicitly on well-being and giving more recognition and rewards for teamwork and team performance: the annual Performance & Development (P&D) interview will have a new format and also a new name. With the acronym GROW (Gesprekken over Resultaat, Ontwikkeling…

During the award ceremony of the Christiaan Huygens Prize on 16 October, mathematician Rosa Schwarz received an honourable mention. Schwarz, former PhD candidate of the Mathematical Institute, received the mention for her dissertation ‘Logarithmic approach to the double ramification cycle’.

Many people have fled to the Netherlands since the outbreak of war in Ukraine, including students. But even before this war, students with refugee backgrounds were eager to study at Leiden University. How does the University help young people from various backgrounds find their way around the Dutch…

PhD candidate Ludwig Hoffmann will spend two years at Harvard University in the US thanks to a Rubicon grant he won on April 11. Using theoretical models he studies biological tissues, for example during morphogenesis. This is the process that causes tissue or organisms to develop their shape. ‘This…

Two Leiden researchers have been awarded a Consolidator Grant by the European Research Council (ERC). This grant of up to 2 million euros will enable them to continue and develop their research.

On January 16, 2022, our respected and beloved colleague Prof. dr. Bas Edixhoven passed away after a short period of serious illness.

ICT, Security

In the ‘Imaginary’ exhibition, its curators show how society is made up of mathematics. From algorithms that save lives to ones that generate art. The exhibition is from 2 June to 25 July at Oude UB in Leiden.

With a healthy dose of logic and creativity, mathematics student Lance Bakker shows how computers can prove complex mathematics. His method proves intricate formulas without calculating every intermediate step. It earned him a nomination for the Leiden Science Young Talent Award 2025.

'It gave our team a big boost to hear that our work was valuable,' says medical chemist Elmer Maurits about the moment they won the Venture Challenge. With their company Iprotics, they want to develop a drug that can better treat patients with autoimmune diseases and blood cancers. 25,000 euros of prize…

The brightness peak of the ring around M87's supermassive black hole has shifted 30 degrees counterclockwise in a year. This is shown by new images released by the Event Horizon Telescope consortium.

Lecture, This Time for Africa! series

Floreat et crescat. Flourish and grow. That was what was wished for the Mathematical Institute at its opening. Now, the institute proudly celebrates its 70th anniversary. Time to reflect on how it all began. And importantly, how is it doing now?

University lecturer Tazuko van Berkel is one of this year's laureates of the Ammodo Science Award. The award includes a sum of 350,000 euros that she can use as she wishes to explore new avenues in basic scientific research.

The Faculty Council is the main consultation and advisory body within the Faculty of Archaeology. Three students and three staff members together represent the Faculty community, advising the board, as well as taking the initiative to put things on the agenda. We speak with council member, and bachelor's…

As of 1 November, Jan Vonk has been appointed full professor of Mathematics at the Mathematical Institute (MI). The institute is delighted with Jan’s appointment, as is he. ‘At the MI we combine the abstract with the concrete like no other.’

Five mathematics students from Leiden University and their coach stood out this summer in Bulgaria at the IMC: the International Mathematics Competition for university students. Lance, Ryan, Casper, Mads and Lars tackled tough maths problems and also made the most of the Bulgarian sunshine.

Sustainable biotechnology, new insights into genome evolution and combining forces in mathematics. The NWO has awarded grants to these three innovative Leiden research projects in the ENW-M Open Competition.

Board members Annetje Ottow and Hester Bijl recently visited the Leiden University Centre for Linguistics (LUCL, Faculty of Humanities) and the Mathematical Institute (MI, Faculty of Science). This was the start of a series of visits to institutes at our university. The focus is on talking to researchers…

It was already the most cited publication ever written at our faculty, but now a new milestone has been reached. Last month, a paper by emeritus professor Jan Reedijk and his co-authors surpassed 10,000 citations — and the count keeps rising.

Six researchers from Leiden University have received an ERC starting grant. This grant of on average 1.5m euros will enable the researchers to launch their own project, form their own research team and develop their best ideas.

No less than four Leiden research teams have been awarded a grant by NWO. On 27 July NWO honoured 21 applications in the Open Competition ENW-XL. NWO awards the grants to consortia in the exact and natural sciences who are doing unconnected fundamental research that is 'driven by curiosity'.

Sara Petrollino, a university lecturer in linguistics, strongly believes that language influences the way we see the world. An NWO Open Competition (XS) grant will enable her to test this hypothesis among the Ethiopian Hamar people. ‘The idea that everyone thinks in geometric shapes is culturally de…

Lecture