The first international laboratory of the two infinities is born

04/07/2021 at 08:00 CEST

Today the first international research laboratory is presented in Japan to simultaneously delve into the physics of the infinitely large and the infinitely small, known as the two infinities.

It is a collaboration between France and Japan to strengthen collaborations between both countries focused on the physics of the two extremes of the universe and develop new common areas of research.

The new scientific institution is called the International Laboratory for Astrophysics, Neutrinos and Cosmology Experiments (ILANCE), the first of its kind in the world.

Its creation responds to an imperative need for the development of scientific knowledge in a field as strategic as the knowledge of matter and energy.

As the French physicist Fran├žois explains, physics still has a lot to do. The current problem is that knowledge progresses asymptotically in the domain of the two extremes, the small and the large.

He adds that, in the current knowledge of the Universe, there are fantastic enigmas to be solved that require the approximation of the two infinities. ILANCE represents the first international step in that direction.

ILANCE will investigate in most areas of subatomic physics, such as Standard Model particle physics and beyond, neutrinos, astroparticles and cosmology, gravitational waves, nuclear structure, and quark plasma.

You will also delve into the frontier of astrophysics, addressing the main questions of cosmology, which are dark matter and energy, to understand the composition of the Universe and its evolution.

For the development of this fundamental research, ILANCE’s efforts will focus on five strategic disciplines for the physics of the two infinities.

Target: neutrinos

Target: neutrinosFirst, neutrinos, which may hold the key to the anomaly detected by XENON1T, the world’s most sensitive detector for the direct search for dark matter. That anomaly could alter the Standard Model.

Franco-Japanese collaboration in this field will focus on an unprecedented search for the diffuse supernova neutrino background (DSNB): it is a theoretical population of neutrinos (and antineutrinos) that cumulatively originate from all supernova events. that have occurred in the Universe.

The detection of diffuse supernova neutrinos allows us to investigate the history of star formation, a key factor in cosmology, nucleosynthesis and stellar evolution. Furthermore, it is vital to understand many aspects of the current universe.

For the development of this research, Japan will replace the current Super Kamiokande observatory (Super-Kamioka Neutrino Detection Experiment) with the new Hyper-Kamiokande neutrino observer, of an order of magnitude greater, in which 13 countries from three continents participate.

Hyper-Kamiokande will range from the study of the CP violation (which can explain why there is more matter than antimatter in the universe), to the decay of protons, atmospheric neutrinos and neutrinos of astronomical origin.

Related topic: A powerful extraterrestrial antineutrino detected at the south pole

The early universe

In this section, the Franco-Japanese collaboration intends to experimentally confirm the hypothesis of a sudden expansion of the Universe in its very early ages (cosmic inflation) and to better characterize the processes that originated them.

To do this, it will be supported by the LiteBIRD project, a new generation satellite mission that aims to detect the trace of the primordial gravitational wave in the cosmic microwave background (CMB) and test the main inflation models of the early universe.

The primitive universe brings together the oldest times in the history of the universe since the Big Bang, when stars, galaxies, clusters and planets had not yet formed.

Inflation signals that the universe underwent a period of rapid expansion an instant after its formation, and provides a compelling explanation for cosmological observations.

Vanucci explains that light atoms took 370,000 years to form after the Big Bang, and then matter was structured into galaxies and stars. Then the planets appeared, adding the heaviest elements produced within the stars. This entire process will be investigated at ILANCE.

Dark matter and energy

Dark matter and energy This is another strategic field of advanced knowledge: dark energy is a form of energy that accelerates the expansion of the universe, while dark matter, which corresponds to approximately 85% of the matter in the universe, does not emit electromagnetic radiation, therefore that we only know of its existence by the gravitational effects it exerts on visible matter.

A cosmological model known as Lambda-CDM explains the nature of these two components and has been successfully tested using supercomputers.

The Franco-Japanese collaboration will deepen this knowledge from the data offered by the Subaru telescope, the most important of the National Astronomical Observatory of Japan.

Installed in Hawaii, the Subaru telescope is a leader in the visible domain and is at the origin of many recent discoveries. For example, in 2019 it played a fundamental role in the detection of a group of protogalaxies made up of twelve galaxies located more than 13,000 million light years from Earth.

This discovery is considered a great find in order to expand the knowledge about the early era of the early universe, when the cosmos was only about 800 million years old.

Gravitational waves

Gravitational wavesGravitational waves are fluctuations generated in the curvature of space-time, which propagate as waves at the speed of light. These waves contract and stretch anything in their path.

The detection of gravitational waves constitutes a new and important validation of the theory of general relativity, which is why there are currently different gravitational wave observation projects, such as LIGO (United States) or Virgo (France and Italy), among others. .

To deepen this knowledge, ILANCE will rely on the Kamioka gravitational wave detector (KAGRA), belonging to the Cosmic Ray Research Institute (ICRR) of the University of Tokyo.

It is the first gravitational wave observatory in Asia, the first in the world to be built underground, and the first to have cryogenic mirrors used in its detector.

Particle Physics and Detectors

Particle Physics and DetectorsIn this chapter, ILANCE sets out to investigate the properties of the Higgs boson with the support of the ATLAS experiment, one of the seven particle detectors built on the Large Hadron Collider (LHC), and the International Linear Collider (ILC), an accelerator. linear electron-positron.

The Higgs boson, which required 20 years of research work, was first observed in 2012 at the LHC. It will likely be replaced by an even bigger throttle that could be installed in Japan.

A Nobel Prize at the helm

A Nobel Prize at the helmMichel Gonin, CNRS research director at the Leprince Ringuet Laboratory, is the director of ILANCE, and the deputy director is Takaaki Kajita, a Japanese physicist known for his experiments for the study and analysis of neutrinos in the Super-Kamiokande.

In 2015 he was awarded the Nobel Prize in Physics, together with Canadian physicist Arthur B. McDonald, for having discovered the weak, but not zero, mass of neutrinos.

For the architects of ILANCE, this launch means that we are at the dawn of very large projects that should answer crucial questions about the two infinities, the Universe and particle physics, as explained in a statement.

Top photo. Credit: ILANCE