A particle of dark matter can be the size of a human cell

A particle of dark matter can be the size of a human cell

New research shows that dark matter can be made of particles, each of which weighs almost as much as human cells and have enough density to become a miniature black hole.

While dark matter is believed to be five sixths of all matter in the universe, scientists still do not know what this strange substance is made of. True to its name, dark matter is not visible - it does not emit, reflects or even blocks light. As a result, dark matter can now be studied only due to its gravitational effects on ordinary matter. And her nature is currently one of the biggest secrets in science.

The authors of a new scientific study said that if dark matter consists of such supermassive particles, then astronomers could detect their signs in the afterglow of the Big Bang.

Previous dark matter studies have largely eliminated all known conventional materials as candidates for those that make up this mysterious material. The gravitational effects attributed to dark matter include the orbital motions of galaxies: the total mass of visible matter in the galaxy, such as stars and gas clouds, cannot explain the motions of the galaxy, so an additional, invisible mass must be present. Scientists still adhere to the opinion that this missing mass consists of a new kind of particles that interact very weakly with ordinary matter. These new particles will exist outside the standard model of particle physics, which is the best current description of the subatomic world. Some dark matter models suggest that this cosmic substance consists of weakly interacting massive particles, or weakly interacting massive particles (WIMP), which are thought to be about 100 times the mass of a proton. This is indicated by study co-author McCullen Sandora, a cosmologist from the University of Southern Denmark. Nevertheless, despite numerous searches, the researchers did not finally find any UHF, leaving open the possibility that dark matter particles could consist of some significant other substance.

Now Sandora and his colleagues are studying the upper limit of the mass of dark matter - that is, they are trying to find out how massive the individual particles could be, based on what scientists know about them. In this new model, known as Planck's interacting dark matter, each of the weakly interacting particles weighs about 1019 or 10 billion billion times more than a proton, or “about as heavy as a particle can be before it turns into a miniature black hole “, Said Sandora to Space.com.

A particle with 1019 proton masses weighs about 1 microgram. For comparison, studies show that a typical human cell weighs about 3.5 μg.

The genesis of the idea of ​​these supermassive particles “began with a feeling of depression, which, it seems, accompanies all efforts to produce or detect UHF and yet does not bring any encouraging clues,” said Sandora. “We still can’t rule out the UHRO script.” But every year there are more and more suspicions that we are not able to notice them. In fact, so far there have been no definitive hints that there is any new physics outside the Standard Model at any available energy scale, so we had to think about the final limit of this scenario. ” This illustration, taken from computer modeling, shows a swarm of dark matter clots around our Milky Way Galaxy.

Sandora and his colleagues considered their guess a little more than curiosity, since the hypothetical mass character of the particles means that there is no way for any particle collider on Earth to produce it and prove (or disprove) such an existence.

But now, researchers have suggested that, if such particles exist, then signs of their existence can be detected in the cosmic microwave background radiation. This is the afterglow of the Big Bang, which created the universe about 13, 8 billion years ago.

Currently, the prevailing view in cosmology is that in the moments after the Big Bang, the Universe has grown to gigantic proportions. This huge growth spurt, called inflation, would smooth out the cosmos, explaining why it now looks mostly the same in all directions.

Studies show that after the end of inflation, the remaining energy heated the newborn universe during an era called “reheating”. Sandora and his colleagues suggest that the extreme temperatures generated by reheating could produce a large number of supermassive particles. This is enough to explain the gravitational effects of dark matter that are currently occurring in the Universe.

However, for this model to work, the heat during reheating would have to be significantly higher than what is generally assumed in universal models. A hotter reheat would, in turn, leave a signature in the relic radiation that the next generation of relic experiments can detect. “All this will happen over the next few years. We hope this will happen in the next decade and nothing more, ”said Sandora. If dark matter consists of these super-heavy particles, such a discovery would not only shed light on the nature of most of the matter in the Universe, but would also give a complete picture of the nature of inflation and how it began and stopped. These are things that, according to scientists, are still very uncertain.

For example, if dark matter consists of these extra-heavy particles, which show that inflation occurred at very high energy, this in turn means that it was able to produce not only temperature fluctuations in the early Universe, but also in its space and time in the form of gravitational waves, ”said Sandora. “Secondly, this suggests that the energy of inflation had to disintegrate into matter extremely quickly, because if it took more time, the Universe cooled to a point where it would not be able to produce any Planck interacting dark matter particles in general” .

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