This year’s Crafoord Laureates in astronomy and mathematics have brought us new knowledge about phenomena that cannot be perceived by the human eye. Douglas Gough, Jørgen Christensen-Dalsgaard and Conny Aerts have developed methods that reveal the secrets inside the Sun and stars. Claire Voisin has specialised in algebraic geometry that can be used to describe shapes which are impossible to visualise.

## The Crafoord Prize in Astronomy

The Crafoord Prize in Astronomy 2024 is awarded to **Douglas Gough**, University of Cambridge, UK, **Jørgen Christensen-Dalsgaard**, Aarhus University, Denmark, and **Conny Aerts**, KU Leuven, Belgium

Seismologists learn about the interior of the Earth by studying how it shakes during earthquakes. The three laureates have discovered that similar methods can also be used in astronomy. The interior of the Sun and stars can be investigated by studying movements on their surfaces, caused by internal oscillations that are similar to soundwaves. This is called asteroseismology.

When Douglas Gough started his theoretical work, he focused on the Sun and soon had the assistance of his doctoral student, Jørgen Christensen-Dalsgaard. He and hundreds of other researchers established a network called the GONG telescopes. This resulted in entirely new discoveries, such as how the interior of the Sun rotates differently to its outer layer.

Conny Aerts used the same method to learn more about distant stars. Thanks to this new technology, researchers are now able to measure the radius of stars and the composition of their interiors and to give them a more precise age.

“Twinkle, twinkle, little star, / how I wonder WHAT you are!” is the text of a well-known nursery rhyme. Small changes that we perceive in a star’s brightness are also due to the oscillations in its interior.

“By establishing an entirely new field of research, which studies the way that stars ‘twinkle’, the laureates have given us the ability to answer the nursery rhyme’s question. We can learn more about the stars’ structure and rotation, as well as about the history of the Milky Way,” says Bengt Gustafsson, Professor Emeritus of Theoretical Astrophysics at Uppsala University, and a member of the prize committee.

### FACTS about the laureates

**Douglas Gough** is Professor Emeritus of Theoretical Astrophysics in the University of Cambridge, UK. He was born on 8 February 1941 in Stourport, Worcestershire, UK, and received his PhD in 1966 from the University of Cambridge.

Douglas Gough, University of Cambridge

**Jørgen Christensen-Dalsgaard** is Professor Emeritus in Astrophysics at Aarhus University, Denmark. He was born on 6 October 1950 in Kolding, Denmark, and received his PhD in 1978 from the University of Cambridge, UK.

Jørgen Christensen-Dalsgaard, Aarhus Universitet

**Conny Aerts** is Professor of Astrophysics at KU Leuven, Belgium, and Professor of Asteroseismology at Radboud University Nijmegen, the Netherlands. She was born on 26 January 1966, in Brasschaat, Belgium, and received her PhD in 1993 from KU Leuven.

### Contact expert

**Bengt Gustafsson**, Professor Emeritus of Theoretical Astrophysics, Uppsala University

bengt.gustafsson@physics.uu.se

+46 73 058 87 34

## The Crafoord Prize in Mathematics

The Crafoord Prize in Mathematics 2024 is awarded to **Claire Voisin**, Institut de Mathématiques de Jussieu, France

Algebraic geometry deals with geometric shapes and structures that can be described as solutions to algebraic equations. Unlike the elementary geometry studied at school, these shapes are often impossible to visualise, and algebraic geometry has developed into one of modern mathematics most theoretically demanding areas.

Claire Voisin has provided important and highly acclaimed contributions in this field, through both counterexamples and strongly positive results for some of the most famous unsolved problems. One such example is the Kodaira problem, about which geometric shapes of higher dimensions that can be described by equations.

Throughout her career, she has also been the leading researcher on the Hodge conjecture, one of the seven Millennium Problems. Recently, she has developed a spectacular method for determining whether geometric shapes are rational, which means they are among the simplest ones. She is also leading in the field of hyperkähler geometry.

Claire Voisin was very surprised when she received the news she was to be awarded such a prestigious prize as the Crafoord Prize.

“If you look at the persons who have got it before me in my field, and in mathematics in general, being part of this group of people is extraordinary!”, she says.

### FACTS about the laureate

**Claire Voisin** is Senior researcher (exceptional class) at the Centre national de la recherche scientifique, CNRS, and works at Institut de Mathématiques de Jussieu, Sorbonne University, Paris. She was born on 4 March 1962 in Saint-Leu-la-Fôret, and received her PhD in 1986 from University of Orsay, Paris.

### Contact expert

**David Rydh**, Professor of Mathematics, KTH Royal Institute of Technology

dary@math.kth.se

+46 73 974 06 35

## FACTS about the prize

The Crafoord Prize is awarded by the Royal Swedish Academy of Sciences and the Crafoord Foundation in Lund, Sweden. The Academy is responsible for deciding the laureates. The disciplines, which change every year, are mathematics and astronomy, geosciences, biosciences, and polyarthritis.

The Crafoord Prize in Mathematics and Astronomy was first awarded in 1982 and Claire Voisin is the first woman to receive the Prize in Mathematics. Previous astronomy laureates include Andrea Ghez and Reinhard Genzel (2012), who have since been rewarded with the Nobel Prize in Physics (2020).

This year’s laureate in mathematics receives six million Swedish kronor. In astronomy the prize amount of six million Swedish kronor is to be shared equally between the laureates. The prize will be awarded at the Crafoord Days in Lund and Stockholm, 13–16 May.

## Press photos

## Press contact

**Eva Nevelius**, Press Secretary at the Royal Swedish Academy of Sciences

eva.nevelius@kva.se

+46 70 878 67 63