The first direct detection of gravitational waves opened the possibility of mapping the Universe via this new and independent messenger.

One of the most important correlation functions in physics, especially in cosmology, is the energy density, which describes how much energy is present at each point in spacetime due to matter fields. A key contribution to the energy density of the primordial universe comes from gravitational waves (GWs),…

Video interview with Subodh Patil, the new assistant professor in Theoretical Cosmology, about the gravitational waves, hidden universes, music, and whether Dutch, Danish and German fit into one brain.

Leiden scientists and companies receive 1.37 million euros to develop technology for the Einstein Telescope. This underground telescope will measure gravitational waves and must therefore be extremely sensitive. To that end, the consortium conducts research on the damping of vibrations at temperatures…

The physical origin of the dozens of stellar-mass binaries, the mergers of which have been detected by the LIGO-Virgo-KAGRA collaboration via gravitational waves, is still unknown.

The ultimate goal of cosmologists is to find a cosmological model able to explain the current observational data.

At the largest scales, two ingredients dictate the distribution of matter in the Universe. The first is dark matter, acting as an invisible scaffolding held together by gravitational forces.

For centuries astronomers studied the Universe by collecting light. Nowadays, we are living in times of great technological advancements, which allow us to explore our Universe in a new way - though gravitational wave radiation.

The Dutch Black Holes Consortium receives 4.9 million euros from NWO for unravelling the mysteries of black holes and other mysteries of the universe. The Astronomy and Society group at Leiden Observatory is affiliated to use the leading research to introduce people of all ages and background, and children…