HIDDeN Outreach

Articles & Interviews

27/09/2024

How symmetries, or lack thereof, shape the universe around

The second most important concept in physics is symmetry. The most important one is how to break them. Symmetries are the guiding principles for building theories. For instance, all astrophysical objects are spherical. This means that gravity has no favourite direction in space; left-right or up-down is the same for gravity. Hence, when we study gravity, we consider it to have rotational symmetry, where all points on a sphere are equally attracted. Similarly, this happens for other forces! Electromagnetism exhibits conservation of charge: all processes in nature preserve that the electric charge at the beginning is the same as at the end, and whatever happens in the middle will not change this fact. So, all the theories that physicists come up with need to take this experimental observation into account.

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29/11/2023

Gravitational Waves: Origin, current progress and future prospects

Predicted long time ago by the Einstein theory of General Relativity, gravitational waves constitute today one the most promising field of modern physics. Only produced by the most violent events of the universe, like mergers of black holes or neutron stars, they have shed light on the intrinsic properties of those objects. Furthermore, the gravitational waves have the potential to reveal the first instant of the universe, dark matter or again dark energy. For these reasons, they have opened a totally new window on our way to observe and understand the universe. In line with that, tremendous efforts are currently spent in order to build efficient telescopes or other gravitational wave detectors. In this article, we recall the main properties of gravitational waves, as proposed initially by Albert Einstein, we then present the recent signals of gravitational waves observed in the currently running experiments. Finally, the futur prospects are discussed.

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25/10/2023

Was our Universe boiling?

Billions of years ago, the Universe we are living in might have looked very different than it does today. In fact there are hints in recent data that the Universe went through a very chaotic and disruptive time. The Universe might have been boiling. But to understand where this hypothesis comes from and how scientists believe they can observe the effects of this boiling we need to take a step back and tell the story of Penzian and Wilson.

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