π Space π Science and technology

Astrophysics: 3 recent discoveries that illuminate our vision of the universe

3 episodes

1

Higgs boson: “We have discovered the origin of matter in the Universe”
2

Crossing a wormhole: reality or science fiction?
3

Gravitational waves: a new era for astronomy

Épisode 1/3

Higgs boson: “We have discovered the origin of matter in the Universe”

Yves Sirois, Exceptional class CNRS research director at École Polytechnique (IP Paris)

On November 3rd, 2021

5 min reading time

Yves Sirois

Exceptional class CNRS research director at École Polytechnique (IP Paris)

Key takeaways

In 1964, theoretical physicists Robert Brout, François Englert and Peter Higgs proposed a mechanism called the 'Higgs field', which permeates the entire universe.
Like all fundamental fields, it is associated with a particle – in this case, the Higgs boson. The Higgs boson is the visible manifestation of the Higgs field, rather like a wave on the surface of the sea.
For many years, there was one major problem: no experiment had ever observed the Higgs boson to confirm this theory.
However, in 2012 the Higgs boson was finally discovered at the Large Hadron Collider (LHC), a particle accelerator located at CERN.
In doing so, particle physics researchers reproduced (in the laboratory) the physical conditions of the first moments of our Universe.

Épisode 2/3

Crossing a wormhole: reality or science fiction?

Isabelle Dumé, Science journalist

On November 3rd, 2021

4 min reading time

Guillaume Bossard

Lecturer in physics at École Polytechnique (IP Paris)

Key takeaways

Wormholes are a staple of science-fiction movies, allowing space travellers to move between two extremely distant points in the universe.
But, in theory, it is impossible to travel through a wormhole without invoking “exotic” effects such as time travel.
Moreover, if a wormhole connects two black holes – and black holes absorb everything in proximity – how then could you escape the force of gravity on the other side?
Nevertheless, recently two physicists, Maldacena and Qi, described a very simplified model of a crossable wormhole that also helps to solve the “Hawking information paradox”.

Épisode 3/3

Gravitational waves: a new era for astronomy

Isabelle Dumé, Science journalist

On November 3rd, 2021

4 min reading time

Paul Ramond

Post-doctoral Fellow in Astrophysics at Université Paris Dauphine-PSL

Key takeaways

Predicted by Albert Einstein in 1916, gravitational waves can only be produced by accelerating very massive objects (such as black holes) at close to the speed of light.
Gravitational waves from a “binary system”, or pair of black holes, were first observed in 2015, thanks to the LIGO observatory in the USA.
Since this first observation, about 50 more coalescence events have been detected, advancing many fields of research and the emergence of “gravitational astronomy”.
LIGO is a collaborative project involving more than 1,000 researchers and engineers in over 20 countries.
The next most promising future project is the European Laser Interferometer Space Antenna (LISA) observatory which should be operational in 2034.

Contributors

Yves Sirois

Exceptional class CNRS research director at École Polytechnique (IP Paris)

Trained in Montreal, Canada, and holding a PhD from McGill University, Yves Sirois was awarded a CNRS silver medal in 2014 and elected Fellow of the European Physical Society in 2019. He is a physicist on the CMS experiment at CERN and has been director of the Leprince-Ringuet Laboratory at Institut Polytechnique de Paris since January 2020.

Other contributions

Higgs boson: “We have discovered the origin of matter in the Universe”

Isabelle Dumé

Science journalist

Isabelle Dumé holds a PhD in physics. She collaborates with various scientific magazines and media, public and private institutions, and actors in higher education and research in France and worldwide.