Les plus anciens amas de matière noire observés dans l’Univers ne sont pas comme prévu !

La carte des fluctuations du rayonnement fossile déduite des observations de Planck. © ESA

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[EN VIDÉO] The secrets of the Planck mission
The Planck satellite is a formidable time machine, capable of revealing several secrets about the origin, structure and composition of the universe. Cosmologists and astrophysicists have used it to map the temperature and polarization fluctuations of the oldest light in the world, that of fossil radiation, in the celestial vault, with unparalleled precision. This video produced by the HFI-Planck consortium, the Canopée communication agency and with the help of Jean Mouette, from the IAP (Paris Astrophysics Institute), explains what this mission consists of.

It took twenty years to prove the existence of neutrinos and about forty for the Brout–Englert–Higgs boson. How long will it take to prove the existence of particles of black matter or on the contrary demonstrate its non-existence?

Remember that the neutrino had been postulated by Born in 1900 in Vienna to a doctor and professor father…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/8/ 9/6 /8965347e36_50142150_pauli-1000.jpg” data-url=”https://news.google.com/science/personalities/physics-wolfgang-pauli-924/” data-more=”Read more”>wolfgang pauli maintain the law of conservation of energy in certain nuclear decays that appeared to violate it. More il avait fallu pour cela admettre that the energy that semblait fires dans le néant était fait emportée par une particule sans masse, sans electric charge et interagissant si peu avec la matière à basse énergie qu’elle pouvait traverser 300 Terre sans s’ stop. We now know that there are in fact three types of neutrinos and that they have masses, albeit very small ones.

Dark matter particles are just as spooky, but paradoxically we need them to explain the existence of galaxies and structures that bring them together in the form of clusters containing from a few hundred to a few thousand galaxies very approximately. It is under the effect of his field of gravitation that ordinary matter collapsed faster than it should have on its own. We know for various reasons that these dark matter particles do not resemble those we know on Earth and that they are produced in particular in collisions of protons at the LHC, although they are being tracked there.

However, although dark matter is one of the pillars of Standard cosmological modelmight not exist and the observations it reports might also be explained by modifying the equations Isaac Newton’s Celestial Mechanics observed that the sum of the forces acting on an object is proportional to its mass and its rate of acceleration. This eminent scientist gave his name to the unit of value of the international system: 1 N is the force necessary to give an object of 1 kg an acceleration of 1 m / s² “Data-url =” https: // news .Google. com/science/definitions/physics-newton-360/” data-more=”Read definition”>newton. One wonders today if the first discoveries of galaxies that seem very primitive by the telescope James-Webb, because observed as they were more than 13 billion years ago, they are not exactly a start of a refutation of the dark matter theory and a confirmation of Mond’s theory.

For 13.8 billion years, the Universe has continued to evolve. Contrary to what our eyes tell us when we look at the sky, what makes it up is far from static. Physicists have observations at different ages of the Universe and carry out simulations in which they reproduce its formation and its evolution. It would seem that dark matter has played an important role from the beginning of the Universe to the formation of the large structures that are observed today. © CEA Research

A new surprise in this sense can be pointing to the tip of your nose and the respiratory system
In humans, the nose is the only part of the respiratory system…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/a/e/7/ae7b9928e8_71945_nose.jpg ” data-url=”https://news.google.com/health/definitions/human-body-nose-14731/” data-more=”Read More”>nose in an article published in Physical Review Letters by an international team of researchers led by members of Nagoya University in Japan. These are some results obtained with the Japanese Subaru telescope, in Hawaii, within the framework of the research campaign of the Subaru Hyper Suprime – Camera Poll (HSC), in combination with other observations obtained by the Planck Satellite of The European Space Agency is Europe’s gateway to space. Its mission is to shape European space capability development activities and make…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/0/9/f/ 09f0b05e28_50034401_logo -esa-fs .jpg” data-url=”https://news.google.com/sciences/definitions/universe-esa-2466/” data-more=”Read more”>THIS in the form of his famous map of cosmic radiation, the oldest light in the The history of the universe begins about 13.7 billion years ago in an extremely dense and hot soup. The laws of physics like us…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/1/5/5/1557798396_80921_universe.jpg” data-url= “https : //news.google.com/sciences/definitions/astronomy-universe-15239/” data-more=”Read more”>Universe observable, emitted about 380,000 after the big Bang in a few thousand years.

Dark matter that distorts the images of galaxies

Let us also remember what the astrophysicist and cosmologist Laurence Perotto, a member of the Planck collaboration, had explained to Futura in the file that he had allowed us to write where he explained the nature of fossil radiation and the analyzes that she and her colleagues had planned to make of this radiation in search of fundamental clues to the cosmology and theoretical physics: The effect of gravitational lens allows to reconstruct the integrated gravitational potential of the surface of the latest Matter Sciences
The action of spreading to achieve a uniform state; result of this action. In the case of light, the reflection, in all directions, of…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/4/6/8/4686984e83_50034253_reflexion -fuse- en.jpg” data-url=”https://news.google.com/sciences/definitions/physics-diffusion-1020/” data-more=”Read more”>diffusion until today. It is an interesting probe of the structures of the Universe. Thus, if we succeed in this reconstruction, Planck would become an autonomous experiment sensitive to the entire evolution of the Universe, from the primordial universe of the time of the last diffusion to us.

The surface of the last scattering is that of a fictitious sphere surrounding any observer in the cosmos observable and showing you the regions from which the The name photon comes from the Greek and means “light”. In fact, the photon transmits the electromagnetic interaction, light being an example of an electromagnetic wave.” data-url=”https://news.google.com/sciences/definitions/physics-photon-3500/” data- more= “Read definition”>photons fossil radiation when the observable Universe became transparent because its density became so low that photons from that time could then travel without colliding with charged particles that would scatter them over great distances.

The evoked gravitational lensing effect, in this case the so-called weak lensing effect or even gravitational shear, is an effect of deflection of light rays by a gravitational field that leads to the deformation of the initial image of a galaxy by a large mass interposed between this galaxy and an observer. We can deduce from the warp the mass of the body that produces it, so measuring gravitational lensing makes it possible to probe mass distributions in the observable cosmos, including masses of dark matter that itself does not radiate.

In a vacuum, light usually travels in a straight line. But in a space warped by a massive celestial body, such as a galaxy, this trajectory is deflected! Thus, a light source located behind a galaxy has an apparent position different from its real position: this is the phenomenon of gravitational mirage. This video originates from the web documentary “ the odyssey of light (http://www.odysseedelalumiere.fr/comp…) and has been integrated into the web documentary ” Embark with the dark matter (lamatierenoire.fr). © CEA-Animea

This effect has been used to estimate the presence and changes in the distribution of dark matter up to about 8 to 10 billion years ago. As Laurence Perotto also explained to us, the weak gravitational lensing effects produced by galaxy cluster and the galaxies in the foreground of the last scattering surface contaminate the study of the fossil radiation and it is necessary to somehow subtract this noise from the signal to return to the primitive state of the fossil radiation. This makes it possible, in particular, to trace the mythical b-mode primitive polarization of fossil radiation. Enhancement of these modes would convincingly demonstrate the existence of a vertiginous inflationary phase of the expansion of space during the Big Bang.

Dark matter clumps that have been structured since the Big Bang

But, as the cosmologist had commented in the extract of her file that we have provided, the measurement of the weak gravitational lensing effect could in theory inform us about the presence and the variable characteristics in time and space of the dark matter from the appearance of the first galaxies until today using fossil radiation.

The Japanese-led team managed to make just such observations beyond 8 billion years by measuring the effects of the galaxies detected with the HSC on the Planck background radiation measurements. We hadn’t gone further before because the galaxies, whose images were distorted by gravitation, were too faint to make valid measurements.

But now researchers can go back some 12 billion years in the observable cosmos.

Surprisingly, although yet to be confirmed, the size characteristics of dark matter concentrations between 8 and 12 billion years ago do not seem to follow the predictions of the Standard cosmological modeldark matter density fluctuations during this period appear weaker than expected.

Yuichi Harikaneone of the authors of the discovery and professor of theCosmic Ray Research Institute of the University of Tokyo, does not hesitate to explain: ” Our conclusion is still uncertain. But if true, that would suggest that the entire model is flawed as you go back in time. It’s exciting because if the result holds after reducing uncertainties, it could suggest an improvement in the model that could provide the nature of dark matter itself. »

With this goal in mind, cosmologists still need to increase the volume and the precision of the available data, which they will soon be able to do with the launch of the Vera C. Rubin Observatory, previously called the Observatory OHSA.

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