Afbeelding
Virgo gravitational wave detector. Credits Nikhef
Facilities and Research
According to Albert Einstein’s (1915) theory of relativity, space and time in the universe form a four-dimensional continuum that behaves like a medium in which vibrations known as gravitational waves can occur. The European Gravitational Observator is located near Pisa, in Italy, where the Virgo detector extends into the flat landscape.
Virgo is Europe’s largest gravitational-wave detector, with two three-kilometre long laser tunnels measuring subtle distortions in the distances between mirrors. Gravitational waves in the fabric of spacetime arise when extremely dense objects, such as black holes, move at extreme speeds during collisions. The resulting vibrations spread out like ripples on a pond. When they reach Earth, they briefly distort distances. Even in kilometre‑scale installations, these distortions are smaller than the diameter of an atomic nucleus—right at the limits of what can be measured.
In 2015, researchers from the two American LIGO detectors and Virgo discovered the first gravitational wave ever, originating from colliding black holes in the universe. The discovery was awarded a Nobel Prize.
Afbeelding
A mirror from the Virgo gravitational wave detector. Credits Nikhef
Collaboration
Nikhef is a full member of EGO/Virgo. The NWO institute makes a significant contribution to the technical development of the instrumentation and to the analysis of the measurements in the collaboration between LIGO, Virgo, and the Japanese KAGRA. Mechanical and opto‑electronic techniques to eliminate vibrations from the system have proven crucial. Nikhef technicians help design and build the equipment.
The Netherlands co‑governs EGO/Virgo through NWO institute Nikhef, together with France, Italy and Belgium. Virgo upgrades have been partly carried out through national and international roadmaps for scientific infrastructure. Virgo is one of the central projects within the Gravitational Waves research programme at Nikhef, spread across several Dutch universities and involving dozens of researchers.
More information
Would you like to find out more about EGO/Virgo, its research and on-site facilities? Then visit the VIRGO-website. You can find more information about the institute Nikhef on the Nikhef website.