The existence of dark matter is without a doubt one of the biggest mysteries in Cosmology, and it’s the structure that makes up more than 80% of the Universe, besides ordinary matter distributed in all the 92 naturally occurring chemical elements. We know for sure that dark matter is a lot more abundant than the matter we encounter day by day, but we don’t know yet what exactly is it and how it came into existence. New research may have finally found a part of the answer in primordial black holes.
Primordial black holes might have created a part of the dark matter
Some astronomers believe that only less than a second after the Big Bang came into existence black holes 50 times bigger than our sun. Of course, it’s tough to capture a picture of a black hole. Therefore, astronomers believe such celestial objects existed at practically the moment of the Big Bang by studying the gravitational waves using the VIRGO and LIGO detectors three years ago, as Alvise Raccanelli from CERN tells us.
He added that there are not few astronomers who support the idea of primordial black holes being the source of at least a portion of the dark matter.
Riccardo Murgia was the lead author of the recent study of the hypotheses of primordial black holes being the source of dark matter, and together with his colleagues Giulio Scelfo and Matteo Viel of SISSA tried to uncover the truth.
Murgia said: “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. Comparing the results of our simulations with the data observed, it is possible to establish limits on the mass and abundance of primordial black holes and determine whether and to what extent such candidates constitute dark matter.”
Stephen Hawking was the first to launch the claim
Despite its well-known health condition, Stephen Hawking was irrefutably one of the smartest guys on the planet. Therefore you can’t ignore what he was saying. Almost half a century ago, back in 1971, he was the one that proposed the idea of “Big Bang Black Holes” being the source of the mysterious dark matter.
Of course, most of us would ask, “but how can a black hole form right after the Big Bang? Aren’t black holes by definition the final remnants of stars after they explode in a supernova?”. Well, in some cases, a black hole isn’t born as a result of a dying star. And if astronomers are claiming this and even Hawking did, it’s worth believing them.
Could dark matter be composed of planet-size particles?
One of the researchers involved in Murgia’s study said: “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).”
As outstanding as it sounds, this means that dark matter may be in the shape of planet-size particles. But aren’t particles very tiny and invisible for the naked eye, by definition? Well, we would be forced to modify the definition itself if the theory proves to be correct. Of course, it’s just a hypothesis, but who knows what huge surprises the Universe can provide to us? It has done nothing but providing enormous surprises for us humans ever since we first started to explore space.
Finally, the results of the study done by Riccardo Murgia and his colleagues seem to rule out the case of all dark matter being created by primordial black holes, but they seem to support the idea that a part of the observable dark matter is a result of black holes formed only less than a second after the Big Bang.