B-PHOT supports VUB's Einstein Telescope expo and public panel this April at Main Campus Etterbeek

Could Belgium soon be listening to the echoes of the Big Bang from deep underground? From 20 to 26 April 2026, the Vrije Universiteit Brussel (VUB) is bringing that question to the public with a week-long interactive exhibition and a free panel discussion dedicated to the Einstein Telescope, the next-generation gravitational wave observatory that may one day be built at the tri-border region of Belgium, the Netherlands, and Germany.

Running at the Braem Building on the VUB Main Campus Etterbeek, the free Einstein Telescope expo invites visitors of all ages to explore gravitational waves, the mysteries of the dark universe, and the extraordinary technologies being developed to detect them. Highlights include a Virtual Reality journey through the Einstein Telescope or a neutron star, an interactive simulation to find colliding black holes in real detector data, a look at what you would look like behind a black hole, and the chance to operate a mini Einstein Telescope interferometer yourself.

The expo is open on the following dates and times:

Entry is free, but visitors are asked to reserve a ticket so organisers can plan capacity.

On the evening of Tuesday 21 April, two VUB professors take the stage for a public panel discussion titled "Van oerknal tot Einsteintelescoop: een nieuwe manier om het heelal te verkennen" — or in English, "From the Big Bang to the Einstein Telescope: a new way to explore the universe."

Prof. Alexandre Sevrin (Physics and Astronomy, VUB) will explain what gravitational waves are and outline the scientific breakthroughs the Einstein Telescope could make possible. Prof. Hugo Thienpont, Director of Brussels Photonics B-PHOT, will discuss the immense technological challenges involved in building such an extraordinarily sensitive instrument, and the role Belgian researchers and companies are playing in meeting them. The conversation will be moderated by Kim Verhaeghe, science editor at Eos Wetenschap.

The event is organised by VUB, Eos science magazine, and ET Vlaanderen, and forms part of the Grijze Cellen ("Grey Cells") public science lecture series by Eos in partnership with FWO, the Research Foundation – Flanders. Admission is free.

On Sunday 26 April, students from the VUB SPIE and OPTICA Student Chapters — which together make up the B-PHOT Student Chapter — will present live demonstrations of light-based technologies. Visitors can discover how light powers LEDs, lasers, fibre optic internet, and sensors in self-driving cars, as well as perhaps more surprising applications: cancer treatment, food quality monitoring, and 3D-printed organs.

Please note: both the expo and the panel discussion are conducted in Dutch.

The Einstein Telescope is one of the 11 research infrastructure priorities identified by the European Strategy Forum on Research Infrastructures (ESFRI), and is often compared in scale and ambition to CERN. A final decision on its location is expected by the end of 2026.

B-PHOT's engineering team is internationally recognised for its expertise in complex optical systems — designing and fabricating advanced lenses and mirrors that can correct even the tiniest imperfections in a light beam. For the Einstein Telescope project, B-PHOT is currently polishing the ultra-sensitive mirrors for the Einstein Telescope Pathfinder, a prototype test facility in Maastricht, while also researching laser and optical cavity systems to deliver the purest possible light signal to the detector.

VUB is also involved through its High Energy Physics Research Centre (HEP), which contributes fundamental physics expertise from experiments including CMS at CERN, IceCube in Antarctica, and LOFAR, as well as through hydrogeological research into the stability and groundwater conditions of the tri-border candidate site.

For tickets and further information (in Dutch), visit the VUB event pages: