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.

The European Space Agency (ESA) has approved the proposal for gravitational wave detector LISA. The launch for the space detector is planned in 2034. ‘A dream that comes true,’ says astronomer Elena Maria Rossi.

What is the connection between materials with weak and strong gravitational interactions?

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.

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

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.

Promotor: K. Kuijken, Co-Promotor: H. Hoekstra

Promotor: Prof.dr. S. Portegies Zwart

Of all the mass in our Universe, 80% is thought to consist of a hypothetical and invisible substance called dark matter (DM).

In this thesis we study bistable reaction-diffusion equations on lattice domains.

Our research primarily focuses on the early universe and its origins in theories that go beyond the Standard Model of particle physics.

In astronomy, the interpration of observations and measurements plays a crucial role: we rely purely and fundamentally on the information that reaches us as observers. And 80% of all matter in the universe is undetectable directly.

In this thesis we study the landscape of gravitational models which modify GR by introducing an additional scalar degree of freedom (d.o.f.) to source Cosmic Acceleration.

This thesis is dedicated to the exploration of the primordial dark ages: unknown physics during the earliest stages of the Universe’s expansion that have not yet been directly probed by observations. Cosmic inflation is a burst of exponential expansion of space after the “Big Bang”.

We are cosmologists, in other words we use physics to study the Universe, how it started and evolved into the structure that we observe around us.

What happens to electrical waves that have to cross gaps in insulation material around nerves in the human body

Promotor: Koen Kuijken Co-promotor: Henk Hoekstra

Promotor: Prof.dr. H. J. A. Röttgering, Co-Promotor: Dr. M. Haverkorn

The elementary excitations of magnets are called spin waves, and their corresponding quasi-particles are known as magnons. The rapidly growing field of Magnonics aims at using them as information carriers in a new generation of electronic devices, (almost) free of electric currents.

The focus of the dissertation

Leiden has a strong tradition in theoretical physics, thoroughly linked with experimental disciplines.

It's one of the big cosmology debates: the universe is expanding, but how fast exactly? Two available measurements yield different results. Leiden physicist David Harvey adapted an independent third measurement method, using the light warping properties of galaxies predicted by Einstein. He published…

‘I could hardly believe my ears when I heard that we had been awarded the Gravitation grant,’ says Berna Güroğlu, professor of the Neuroscience of Social Relations. This grant is awarded by the state, via NWO, to pioneering scientific top research. In terms of grants, this really is something special,…

For centuries, astronomers have studied the universe by collecting light signals. Since 2015, the confirmation of an important prediction of Einstein allows us to explore the universe in a new way: through gravitational wave radiation. Astronomy PhD candidate Valeriya Korol proposes to use these gravitational…

Three major research projects involving Leiden scientists have been awarded a grant from NWO’s Gravitation Programme. The projects are on innovation processes, organs-on-chips and quantum software.

The 2017 Nobel Prize in Physics has been awarded to Rainer Weiss, Barry Barish and Kip Thorne for their work on the measurement of gravitational waves. Thorne was Lorentz Professor in 2009 in Leiden. Physicist Jan Willem van Holten explains why this is such an important discovery. ‘A new branch of astrophysics…

Leiden University is involved in five new NWO Gravitation projects. Two relate to mental disorder and the remaining three to a healthy lifestyle, the combination of human and artificial intelligence, and the special relationship between plants and microbes.

Galaxy intrinsic alignments induce a major astrophysical contamination to weak gravitational lensing measurements and need to be modelled and mitigated when extracting cosmological information from such measurements.

Vibrating carbon monoxide molecules adsorbed at the surface of a salt crystal stop moving after a few milliseconds. Scientists now discovered this is dominantly due to the emission of electromagnetic waves. The role of the chemical bond at the surface thereby appears to be less important than previously…

By comparing the archaeological evidence at Sedgeford and other sites located on both English and Continental coastal zones, what evidence is there for a shared maritime culture between these North Sea communities? Also if evidence is found, can we reveal to some extent a separate coastal identity to…

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…

The project Hybrid Intelligence receives 19 million euros from the Gravitation programme of the Dutch Research Council (NWO). The consortium consists of six Dutch universities and combines human and artificial intelligence, aiming to amplify human intelligence instead of replacing it. Leiden professors…

How can young people grow up successfully and contribute to the present and future society? The consortium that is researching this will receive 22 million euros within the scope of the Gravitation programme.

The project MiCRop receives 20.3 million euros from the Gravitation programme of the Dutch Research Council (NWO). MiCRop will unravel the microbial community around crops. This knowledge will help to develop more sustainable crops that require fewer fertilizers and pesticides. Leiden professors Jos…

Gravitation programme grant Co-applicants Bernet Elzinga en Andrea Evers are two of the captains of the six teams, all led by main applicant Anita Jansen, Maastricht University.

Of the 17 Rubicon grants that NWO recently awarded, three have gone to researchers at Leiden University. They can spend a longer period of time doing research at an institute abroad.

Over 1600 astronomers and space scientists will gather online from 29 June until 3 July for the annual meeting of the European Astronomical Society (EAS). The virtual meeting will also host NAC 2020, from 1 July until 3 July: the 75th Conference of the Royal Netherlands Astronomy Society (NAC).

This dissertation is an experimental study of laser-generated, atmospheric pressure, transient toroidal helium plasmas.

Lecture, Studium Generale

Electrical signals travel like a wave through our neural pathways. The mathematical models for these movements could not yet properly describe all the biological properties of the nerves. PhD student Willem Schouten-Straatman changed this by improving the existing models. ‘I hope that one day we will…

Galaxies form and live inside dark matter haloes. As a consequence, they are exposed to the tidal fields generated by the surrounding matter distribution: this imprints a preferential direction to the galaxy shapes, which leads to a coherent alignment on physically close galaxies, called intrinsic a…

In this thesis, the research focuses on the properties of dark matter and dark matter haloes and how they connect with the galaxies we can observe in the Universe.

Professor Frank den Hollander has been awarded a 10-year grant through the NWO Gravitation program, jointly with colleagues from the University of Amsterdam, the Center for Mathematics and Computer Science in Amsterdam, and the Technical University of Eindhoven.

Bright explosions appear all over the radio and gravitational-wave sky. This dynamic side of the universe which has just been discovered, can be mapped by self-learning machines. The National Science Agenda granted 5 million euro’s to CORTEX, the Center for Optimal, Real-Time Machine Studies of the…

Leading scientists in the field of the ethics and philosophy of technology are currently revising time-honoured key philosophical concepts such as autonomy, justice and responsibility, as these concepts are being challenged as a result of new technological developments. They receive 17.9 million euros…

Professor Renata Kallosh (Stanford University), one of the world’s leading theoretical physicists, will be this summer’s Lorentz Professor at the Leiden institute for theoretical physics. Her main areas of interest are cosmology and string theory. She studied physics in Moscow, where she also obtained…

Three major cosmology-focused missions are planned for the next decade: the Euclid space telescope, the Vera C. Rubin Observatory in Chile, and the Nancy Grace Roman Space Telescope.

In this thesis, we study travelling waves in stochastic reaction-diffusion equations. We extend techniques from the deterministic theory for travelling waves to apply to the stochastic version, which allows us to compute the stochastic wave speed and shape, and draw conclusions on the stability of the…