Light Dark Matter
The project ”Light Dark Matter” aims to approach the still unsolved question on the nature of the ubiquitous, yet unknown dark matter. The most popular hypothesis the last decades has been that dark matter is made of particles with masses in the range of one proton mass to thousands of proton masses, so relatively heavy for being elementary particles. While efforts in Stockholm and elsewhere are intensive to find these type of particles, it is time to start open for the possibility that the current paradigm might be too narrow. With this in mind, the project, lead by Torsten Åkesson at Lund University, with Jan Conrad at Fysikum being co-applicant will address a particular window for new particle candidates, namely that of “light dark matter” i.e. particles below about one proton mass. One part of the project is focused on participation in the “Light Dark Matter eXperiment”, LDMX, an experiment aiming at producing and detecting “Light dark matter” at a particle accelerator. The initial phase will be an experiment at the Stanford Linear Accelerator Center in the US. This experiment will be the most sensitive experiment to many of the proposed ligh dark matter particle candidates. Other parts of the project, led by Jan Conrad and colleagues at Chalmers Technical University, focus on possibilities to detect these particles from the Cosmos and combining different detection mechanisms, which will be necessary to proof that new particles produced at accelerators are really the dark matter. The project will receive a grant of SEK 26,000,000 over five years.

Gravity Meets Light
The project “Gravity Meets Light” focuses on the study of mergers of compact objects where both gravitational waves and ordinary light is produced. In 2017, GW180817, a merger of two neutron stars was detected by gravitational wave interferometers and by a multitude of telescopes throughout the electromagnetic spectrum for the first time. This “multi-messenger” event, ranked as the Science breakthrough of year 2017, provided us with important new insights in physics, e.g., evidence for the cosmic origin of heavy elements like gold and key clues on the nature of short gamma-ray bursts. Furthermore, GW170817 demonstrated the power of these “standard sirens” to measure cosmological distances. The project “Gravity Meets Light” aims to turning mergers of compact objects into a precious tool for precision cosmology. This effort is led by Hiranya Peiris and Ariel Goobar at Fysikum. The development of the methods to extract accurate distance measurements from populations of standard sirens could help shed light on some of the most intriguing puzzles in our understanding of our Universe, and possibly arbitrate in the tension between current state-of-the-art distance ladder and cosmological measurements of the Hubble constant. If the difference persists, it may be a sign of new physics. In the five-year project, which was awarded SEK 33.5 million from the Knut and Alice Wallenberg Foundation, several different research areas in the Oskar Klein Centre are linked together to study different aspects and effects of mergers involving neutron stars.
Dynamic Quantum Matter
Quantum technology, which is predicted to overtake today's silicon-based electronics, has enormous potential. However quantum matter is notoriously difficult to study, partly because many microscopic properties of quantum matter have a complex intrinsic dynamics. The project "Dynamic Quantum Matter", led by Alexander Balatsky at Nordita (hosted by SU) in collaboration with Emil Bergholtz at Fysikum and other theorists in Uppsala and KTH, aims at developing new phenomenology and methods for understanding these dynamic processes focusing on the intricate interplay between interactions, disorder, dissipation and external drives. In addition, there will be the possibility to test these theoretical models in the laser laboratory of Stefano Bonetti, also at Fysikum. Here, some of the materials that theory will deem to be promising, will be investigated by means of intense, ultrafast laser fields with wavelength from the near-infrared to the terahertz region. Most of the experiments will be performed at cryogenic temperatures where the "randomness" caused by high temperature, can be greatly reduced. The project receives a grant of SEK 28,000,000 over five years.
The Knut and Alice Wallenberg Foundation grants are awarded every year to research projects that are deemed to have the potential to lead to future scientific breakthroughs. In 2019, the foundation awarded SEK 640 million to 20 research projects. Four of these grants, totaling just over SEK 132 million, go to Stockholm University.