Dark matter actually derives its name not from its color but from the mystery that surrounds it. Astrophysicists still don't know much about this mass that makes up the bulk of the universe. But now experts start to realize that they understand it even less than they thought. This mysterious matter seems to be even more complex than expected.
Despite the fact that dark matter makes the main ingredient of the universe, at up approximately 80% of its mass, scientists know surprisingly very little about it. They were never been able to even seen it. The existence of the dark matter in the universe is only hypothesized based on observations of its effects on gravity.
"We are confident that it's there, that has mass and that it tugs on itself and on other things via gravity," According to James Bullock, a professor of physics and astronomy at the University of California, astrophysicists are confident that the dark matter is out there, that it has a mass that "tugs on itself and on other things via gravity".
Bullock added in his interview for Quanta Magazine that much of the ignorance of modern physics on dark matter topics comes from the fact that the scientific studies of the universe depend on the observation of light. For example, a distant planet can be only observed when they pass between their host star and the observer.
When studying dark matter, scientists confront with the challenge that this special type of matter neither absorbs nor reflects light. That makes it exponentially more difficult to be observed. Astrophysicists have come with some hypothesizes to explain dark matter.
According to Bullock, they had to create some first-guess models that suggest the dark matter is composed of particles that don't really "interact with much of anything". Another hypothesis is that if dark matter is complex than that means that 80% of the universe is also complex.
With advances in science and technology, researchers are beginning to probe these dark sectors of the universe that are primarily located in the centers of galaxies. The main topic of interest for astrophysicists is to observe dark matter's effects on gravity and then compare their observations with computer models to evaluate which hypothesis best fit the existing universe. However, the problem is that neither hypothesis on a dark matter entirely matches the observations.
The scientists have thought at first that they are interpreting the data wrong, according to Bullock. But now the question comes down to find out whether galaxy formations eject somehow dark matter or the modern physics need to change its theory of dark matter altogether.