Extreme phenomena in our universe, from the infinitely small to the infinitely large

On the evening of 29 September 2022 RSC Belgium welcomed back, once again, Professor Vincent Lemaitre from Universite Catholique de Louvain to discuss the latest thinking in high energy and astrophysics in a talk on ‘Key experiments probing extreme phenomena in the universe from very small to very large scale structures’. His talk was our first in-person talk since the COVID pandemic and was hosted at the British School of Brussels. This event was also the prize giving ceremony for our Chemistry Challenge 2022 for school students.

Scientific knowledge is forged through observation of nature and the development of scientific theories. The latter must not only explain observations, but they must also make predictions that can be verified by experiments! By construction, and contrary to beliefs, scientific theories are therefore falsifiable by possible observations not predicted or understood by theories. Present theories are therefore doomed to be replaced by new ones, more complete and more efficient. The key element for the development of new theories is therefore our ability to observe nature in its smallest corners and extreme conditions - at different spatial and temporal scales, and at different levels of structural complexity.

In the talk, Prof Lemaitre took us through three recent experiments in physics that allow us to observe (or reproduce the conditions of) extreme phenomena in our universe, from the infinitely small to the infinitely large.

They were:

• The CMS experiment at the LHC (Particle Physics and the discovery of the Higgs boson)
• The LIGO/VIRGO experiments (General Relativity and the discovery of gravitational wave), and
• The ICECUBE/KM3NeT experiments (Physics of Astroparticles and the first observation of Blazers – a form of supermassive black hole - with neutrinos).

After presenting the main result(s) obtained by these significant projects, Vincent briefly discussed some future experimental projects in each of these research fields.

The talk was followed by a networking reception where the discussion continued.

We had hoped to combine the live 'in-person' event with a webinar version but a few technical hitches prevented this and we also were unable to record a video version of the event. Our apologies for this.