All Galaxies Including Our Own Are Embedded Within A Vast Sphere Of Black Holes Which Are About 30 Times The Mass Of The Sun
Dark matter is something that is massively regarded as an exotic particle and is more like an obscure substance made out of most of the material universe. Another fascinating rather captivating theory suggests that the dark matter is made up of black holes which were configured when the universe first came into its existence. This view is called primordial black holes. NASA's Goddard Space Flight Center in Greenbelt, Maryland’s scientist explained how the mere interpretation of the phenomenon mentioned above corresponds to the knowledge of cosmic infrared and X-Ray background glows. He also suggested how this will exhibit the reason behind the unanticipated discovery of high masses of black hole mergers last year.
"This study is an effort to bring together a broad set of ideas and observations to test how well they fit, and the fit is surprisingly good," said Alexander Kashlinsky, an astrophysicist at NASA Goddard. "If this is correct, then all galaxies, including our own, are embedded within a vast sphere of black holes each about 30 times the sun's mass."
A team of astronomers was led by Kashlinsky back in 2005 using NASA's Spitzer Space Telescope. The team’s agenda was to figure out the effect on a part of the sky of the background glow of infrared light. In the end the researchers were able to conclude that the glow had undue patchiness and the reason behind this excessive patchiness was likely to be the aggregate light of the primary sources that illuminated the universe 13 billion years ago. Recent studies and the ones that followed this research led by Kashlinsky also showed similar patterns hence confirming that cosmic infrared background (CIB) exhibited unexpected rather disproportionate structures in some parts of the sky.
One of the most unresolved issues in the field of astrophysics is the nature of dark matter. Although scientists have been favoring models that show dark matter as an exotic massive particle, they still haven’t been able to show enough evidence to show the existence of these “so called” particles. NASA has been investigating this issue under its Alpha Magnetic Spectrometer and Fermi Gamma-ray Space Telescope missions.
"These studies are providing increasingly sensitive results, slowly shrinking the box of parameters where dark matter particles can hide," Kashlinsky said. "The failure to find them has led to renewed interest in studying how well primordial black holes -- black holes formed in the universe's first fraction of a second -- could work as dark matter."
There have been several ways proposed by physicists in which, the rapidly expanding universe would be able to produce primordial black holes, in a matter of thousandths of a second right after the Big Bang. The older the universe the larger the black holes can be and because the creation time lasts only a thousandth of a second, physicists believe that these primordial black holes would exhibit a narrow range of masses.
An event happened on September 14 which marked the first ever detection of gravitational waves and the first ever detection of black holes by scientists. In the event a pair of merging black holes around 1.3 billion light years away were captured by the Laser Interferometer Gravitational-Wave Observatory (LIGO) facilities in Hanford, Washington and Livingston Louisiana. The signal that was provided gave LIGO scientists some very unexpectedly large and surprisingly similar information. The values that the scientists received showed that individual black holes has masses of about 29 and 36 times the mass of the sun, plus minus four solar masses.
"Depending on the mechanism at work, primordial black holes could have properties very similar to what LIGO detected," Kashlinsky explained. "If we assume this is the case, that LIGO caught a merger of black holes formed in the early universe, we can look at the consequences this has on our understanding of how the cosmos ultimately evolved."
Kashlinsky showed that if the black holes play their role of dark matter then this process occurs much more rapidly and easily produces the CIB in Spitzer data, even if only a small number of the minihaloes eventually produce stars. As the hot gas falls onto the minihaloes, some of it would also be captured by the black holes that they constitute of. Matter falling towards black holes heats up and produces X-rays and these along with infrared light from the first stars account for the agreement between the patchiness of the CIB and the Cosmic X-ray background (CXB). Sometimes some primordial black holes pass close enough that they become gravitationally pulled into binary systems.
"Future LIGO observing runs will tell us much more about the universe's population of black holes, and it won't be long before we'll know if the scenario I outline is either supported or ruled out," Kashlinsky said.
The NASA team led by Kashlinksy is situated in Goddard and is participating in the European Space Agency’s Euclid mission which will launch in 2020. The project called LIBRAE will allow the observatory to investigate the source of populations in the CIB and with high precision allow them to determine which portion of those were produced by black holes.