From primordial black holes new clues to dark matter

black hole
This computer-simulated image shows a supermassive black hole at the core of a galaxy. The black region in the center represents the black hole's event horizon, where no light can escape the massive object's gravitational grip. The black hole's powerful gravity distorts space around it like a funhouse mirror. Light from background stars is stretched and smeared as the stars skim by the black hole. Credit: NASA, ESA, and D. Coe, J. Anderson, and R. van der Marel (STScI)

Primordial black holes (PBHs) are objects that formed just fractions of a second after the Big Bang, considered by many researchers among the principal candidates in explaining the nature of dark matter, above all following direct observations of gravitational waves by the VIRGO and LIGO detectors in 2016. "We have tested a scenario in which dark matter is composed of non-stellar black holes, formed in the primordial universe," says Riccardo Murgia, lead author of the study recently published in Physical Review Letters. The research was carried out together with his colleagues Giulio Scelfo and Matteo Viel of SISSA—International School for Advanced Studies and INFN—Istituto Nazionale di Fisica Nucleare (Trieste division) and Alvise Raccanelli of CERN.

"Primordial black holes remain hypothetical objects for the moment, but they are envisaged in some models of the primordial universe," says Raccanelli of CERN. "Initially proposed by Stephen Hawking in 1971, they have come back to the fore in recent years as possible candidates for explaining . It is believed that dark matter accounts for approximately 80 percent of all matter present in the universe, so to explain even just a small part of it would be a major achievement. Looking for evidence of the existence of PBHs, or excluding their existence, also provides us with information of considerable relevance on the physics of the ."

Cosmic Forests and Spider Webs

In this work, the scientists concentrated on the abundance of PBHs that are 50 times more massive than the sun. In short, the researchers have tried to better describe several parameters linked to their presence (specifically mass and abundance) by analyzing the interaction of the light emitted from extremely distant quasars with the cosmic web, a network of filaments composed of gas and dark matter present throughout the universe.

Within this dense weave, the scholars have concentrated on the so-called Lyman-alpha forest, the interactions of photons with the hydrogen of cosmic filaments, which presents characteristics closely linked to the fundamental nature of dark matter.

Between Supercomputers and Telescopes

Simulations carried out using the Ulysses supercomputer of SISSA and ICTP have been able to reproduce the interactions between photons and hydrogen. The models have been compared with real interactions detected by the Keck telescope in Hawaii. The researchers were then able to trace several properties of primordial black holes to understand the effects of their presence.

"We used a computer to simulate the distribution of neutral hydrogen on sub-galactic scales, which manifests itself in the form of absorption lines in the spectra of distant sources," says Murgia. "Comparing the results of our simulations with the data observed, it is possible to establish limits on the mass and abundance of and determine whether and to what extent such candidates constitute dark matter."

The results of the study seem to disadvantage the case that all dark matter is composed of a certain type of primordial black hole (those with a mass greater than 50 times that of the sun) but they do not totally exclude that they could constitute a fraction of it.

"We have developed a new way to easily and efficiently explore alternative scenarios of the standard cosmological model, according to which dark matter would instead be composed of weakly interacting massive particles (WIMPs)."

These results, important for the construction of new theoretical models and for the development of new hypotheses about the nature of dark matter, offer much more precise indications for tracing the intricate path to understanding one of the largest mysteries of the cosmos.


Explore further

Is dark matter made of primordial black holes?

More information: Riccardo Murgia et al. Lyman- α Forest Constraints on Primordial Black Holes as Dark Matter, Physical Review Letters (2019). DOI: 10.1103/PhysRevLett.123.071102
Journal information: Physical Review Letters

Citation: From primordial black holes new clues to dark matter (2019, September 17) retrieved 18 October 2019 from https://phys.org/news/2019-09-primordial-black-holes-clues-dark.html
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Sep 17, 2019
Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.

The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.

Sep 17, 2019
Dang, now they have gone full pop science, writing the article for reaction by non scientists rather than reporting actual science research.
Should work, but I get my unicorn news from you tube, where science dares not tread.

Clicks are money and money pays the wages. Look for more of this as time goes by.

Waiting for this to be tied into the rotating electric universe filled with supersolid mystery objects made of plasma dancing on the head of a pin.

Sep 17, 2019
ah ethe, you forgot ti include that as there is not enough time for space?
thereintoforth, there is no space for the last rime
"somebody" keeps forgetting to wind the clockwork orange!

no wonder drunken hooligan deities keep tripping over plasmaspastic accretion disks & falling into the Black Holes!

ooh! a bright flash thereaway...
musta been a big one!

Sep 18, 2019
The press release is a bit fuzzy on the physics of the standard cosmological model, since WIMPs are just the elementary particles that are sneaking into the constraints of weakly weak-EM interaction at most. Purely gravitationally acting particles are also allowed.

Dark matter is a supersolid

they have gone full pop science


No, a gas is not a solid, and this was published in peer review - so it is rather that comment that is pop science balderdash.

Both blocked for repeated inane trolling.

Sep 18, 2019
gosh torbjorn
your word choice of "inane"?
i'd opinionate that "mundane"would be a more accurate description

Sep 21, 2019
There are no black holes. No dark matter. And time is not a dimension. Accept simple facts then build theories.
Oh, and there is no gravity too, only entropy costs.

Sep 23, 2019
There are no black holes. No dark matter. And time is not a dimension. Accept simple facts then build theories.
Oh, and there is no gravity too, only entropy costs.


Okay directly to ignore, got it!

Sep 23, 2019
gosh torbjorn
your word choice of "inane"?
i'd opinionate that "mundane"would be a more accurate description

Watcha talkin' 'bout Willis?
In your case, it's obvious he missed that crucial "s" in inane.

BTW. Next time try --- not enough time for space odyssey.

Oct 16, 2019
Almost there - It is not that dark matter is made up of black holes, but rather that black holes are made up of dark matter. This consideration is better understood by thinking of gravity a bit differently. Where the universe's total energy is broken down to as 68% dark energy, 27% mass-energy via dark matter, and 5% mass-energy via ordinary matter. In which case, as black holes are significantly more energy dense than ordinary matter, it would be more logical that black holes would be a product of dark matter. If we assume that dark energy, being the largest distribution of total energy, represents the foundation for space-time and provides for a net zero inclusion of matter as a whole, or 100% of the total universal energy. Another way of looking at this relationship is that dark matter insulates the ordinary matter from being torn apart within their dark energy medium. The greater the negative mass density, the greater the space-time displacement (or warping).

Oct 16, 2019
Thinking of gravity as the force involved in the paired creation of matter, as a whole, it then follows that this complementary dark matter is representative of the gravitational force that binds ordinary matter. Consequently, dark matter is what engenders the force of gravity through the displacement, or warping, of space-time. Subsequently when this complementary relationship is severed, ordinary matter is disintegrated and discarded out back into the cosmos, leaving dark matter to remain as a displacement in space-time. This is what happens when matter, as a whole, is separated upon the event horizon of a black hole.

Whereupon the black hole is not infinitely dense, but rather it is a degree of negative mass density. The greater the negative mass density, the greater the space-time displacement (or warping). Currently there is no known calculation as to what degree of negative mass density displacement is considered to much or too little.

Oct 16, 2019
Subsequently upon this hypothesis then one can expect that there is a required transition to separate ordinary matter from its complementary dark matter. It starts first with the disintegration of matter, as a whole, as it interacts with the black hole's event horizon. As ordinary matter is 'squeezed', for lack of a better description, upon its own gravitational acceleration toward the black hole, liken to the spaghettification effect, its structure is contorted and distorted to allow for its disintegration via transmutation. The transmutation provides for a massive release of photons due to the alpha and beta decay of its atomic structure. This 'squeezing' effect causes the extraction of the complementary dark matter from the whole matter, allowing for the ordinary matter to be reduced to its smallest constituent components. The dark matter is then absorbed into the black hole, as the remnants of ordinary matter are discarded and radiated out at high velocity back into the cosmos.

Oct 16, 2019
Therefore, while we think of ordinary matter as separate of dark matter, it turns out that they are part and parcel of our existence in the universe. In this case, dark matter is the manifestation of the gravitational force that imbibes within and without ordinary matter. Without dark matter, ordinary matter would disintegrate within the universal medium of dark energy. Consequently, it is dark matter that engenders the force of gravity that allows ordinary matter to bind together. As this complementary displacement insulates the newly created ordinary matter (positive mass density) in an envelope of dark matter (negative mass density), the balance of the continuum is retained in a zero sum manifestation of total energy.
If you're interested in exploring this as hypothesis in the grander scheme of the universe, you can review the book, 'The Evolutioning of Creation: Volume 2', or even in the reimagined ramifications of these concepts in the sci-fi novel, 'Shadow-Forge Revelations'.

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