Understanding when physicists and astronomers explain to us what the universe is and how it works is not always easy. Some people have been talking to us about dark matter for a long time. They did it Through speculation and mathematicsBut without showing us anything. This could have changed thanks to the Fermi Gamma Ray Space Telescope.
This telescope would have provided direct evidence of dark matter, allowing this invisible matter to be “seen” for the first time. Those quotes have their meaning Because dark matter cannot be seen. That is, it cannot be observed directly because the molecules that make it up do not interact with the electromagnetic force, which means that it does not absorb, reflect, or emit light.
So its name indicates that it is considered as such It does not emit any type of electromagnetic radiation (Like light). Scientists have recorded its effects on observable matter, but they have not been able to observe it directly.
Dark and secret, but abundant
Astrophysicists estimate that ordinary (visible) matter represents only 4% of the universe, compared to approximately 26% will be dark matter. However, this “glue” of the universe is one of the greatest mysteries of modern physics. Nor can scientists decipher its nature.
Its existence was achieved in 1933 by Swiss astronomer Fritz Zwicky. He noticed that galaxies move through space faster than would be expected given their mass. He’s done the math. So Infer the existence of an invisible structureDark matter, which holds galaxies together. Without this matter, galaxies would disintegrate due to their rotation, because the gravity generated by visible matter would not be sufficient.
After Zwicky Other observations indicate that it may exist Of dark matter in the universe. Starting from the rotation speed of the aforementioned galaxies to the gravitational lensing of objects by galaxy clusters, through to the temperature distribution of hot gas in galaxies, galaxy clusters and nebulae.
Hawking: Dark matter in black holes
Physicists believe that during the Big Bang the first stars and galaxies were formed thanks to dark matter. In those early stages of the universe, This material served as a “scaffold.” So that ordinary matter can be put together.
Stephen Hawking has his theory too. In 1974, he proposed to Bernard Carr That black holes were not dark wellsBut it is possible that it emitted some form of quantum radiation. The two physicists proposed the existence of primordial black holes (after the Big Bang) that represent all the dark matter in the universe.
that Dark matter can hide in black holes It was the main theme of Hawking’s work. The study of black holes has led to increased interest in dark matter and dark energy. The interaction between these elements could provide clues about the structure of the universe and its future evolution.
What is dark matter made of?
The composition of dark matter is unknown. There are many theories and speculations. They can consist of exotic subatomic particles, ordinary heavy neutrinos, astronomical objects such as dwarf stars or astronomical objects (collectively called MACHOs), or clouds of non-luminous gas.
It is also possible that dark matter is composed of… Macromolecules interact weakly (weakfor its abbreviation in English). They are heavier than protons, but they interact little with matter. But there is no certainty.
View of the Fermi telescope
The Fermi Gamma Ray Space Telescope was launched into orbit on June 11, 2008 from a Delta 2 rocket, launched from Cape Canaveral (USA). It was designed for Studying the sources of gamma rays in the universe In order to detail a map for them. It is a large area telescope (‘Large area telescope‘) Its name is in honor of the Italian physicist Enrico Fermi.
The mission is funded by NASA, the US Department of Energy (DOE) and funding agencies from France, Germany, Italy, Japan and Sweden. With Fermi, an international team of more than 150 scientists works Mapping the entire sky in search of astrophysical phenomena Such as active galactic nuclei, pulsars, or supernova remnants.
The telescope follows a Low circular orbit (550 km altitude) with a duration of 95 minutes. Thanks to its capabilities, Fermi provides a huge amount of data from the universe, which is available to the scientific community. This is what a team led by astrophysicists from the University of Tokyo did.
Does dark matter emit gamma rays?
They studied the latest data from Fermi, focusing on regions where dark matter should be concentrated, such as the center of our galaxy. Now they could confirm the result: No Detection of specific gamma rays It was predicted by the annihilation of theoretical dark matter particles.
They claim to have discovered a specific type of gamma ray, which will be… As a result of the annihilation of theoretical dark matter particles. They explain this in a study conducted by the University of Tokyo that they publish Journal of Cosmology and Astroparticle Physics.
“We detected gamma rays with a photon energy of 20 GeV (or 20 billion electron volts, which is a very large amount of energy) extending in a halo-like structure toward the center of the Milky Way. It is very similar to the expected shape of a dark matter haloProfessor Tomonori Totani, from the Department of Astronomy at the University of Tokyo, says.
These gamma-ray measurements cannot be easily explained by other more common astronomical phenomena or by gamma-ray emissions. Therefore, Al-Totani believes that this data constitutes strength An indication of the emission of gamma rays from dark matterwhat has been researched for many years.
Now is the time to confirm it
If the result is confirmed, so be it “One of the great discoveries in the history of science,” As researcher from the Autonomous University of Madrid and the NASA Fermi-LAT collaboration Miguel Angel Sánchez Conde told Efe.
“Unfortunately, despite it being a serious undertaking.” It contains great uncertaintiesHe told the science resource platform Science Media Center that it is impossible to confirm that this is the first time dark matter has been seen.
Professor at the Complutense University of Madrid, Juan Abel Barrio, questions the quality of the article and puts it to rest Trust in the researchers who are part of the Fermi collaboration“We have not yet found any statistically significant evidence that gamma rays are coming from dark matter,” said Ivey.