What dark matter actually is remains a mystery but it was first conceptualised in 1977 by scientists who suggested that the substance, which is thought to make up 85 percent of all matter in the universe, is responsible for all of the unseen matter in space.
Its existence would go towards explaining why galaxies rotate and why they stick together, rather than stars flying off in all directions.
Now a team of Russian researchers have added more intrigue to one of the most curious cases in the history of the universe, by saying dark matter could yield ‘dark stars’ and ‘shadow civilisations’ which are completely invisible to us.
With the current understanding of dark matter, it could be possible for the substance to clump together, the team state in a paper published in the journal Physical Review Letters.
And this is where it gets tricky.
Dark matter could also be made up of a plethora of particles which just do not interact with matter and particles in our known universe.
This would mean an entire universe could be invisible to us and residing within our universe too.
The researchers theorise that ‘Bose’ stars could exist in the darkness surrounding galaxies.
Physicist Dmitry Levkov from the Institute for Nuclear Research of the Russian Academy of Sciences said: “In our work, we simulated the motion of a quantum gas of light, gravitationally interacting dark matter particles.”
To test this, the researchers wanted to understand how a dark matter Bose-Einstein condensate could form.
Put simply, a Bose-Einstein condensate, in matter we understand IE not dark matter, is a state of matter consisting of gas and particles which are cooled to almost absolute zero (-273.15°C). The researchers wanted to understand if this could be achieved in dark matter.
In theory, a dark matter Bose-Einstein condensate could form under the intense gravitational pull of gravity and condense into superfluids.
Dr Levkov said: “We started from a viralised state with maximal mixing, which is kind of opposite to the Bose-Einstein condensate.
“After a very long period, 100,000 times longer than the time needed for a particle to cross the simulation volume, the particles spontaneously formed a condensate, which immediately shaped itself into a spherical droplet, a Bose star, under the effect of gravity.
“The next obvious step is to predict the number of the Bose stars in the Universe and calculate their mass in models with light dark matter.”
And if these Bose stars do exist, it could open up a whole possibility of what else could reside in dark matter, including the possibility of shadow beings.
Theoretical physicists Lisa Randall states: “It seems very odd to assume that all of dark matter is composed of only one type of particle.
“An unbiased scientist shouldn’t assume that dark matter isn’t as interesting as ordinary matter and necessarily lacks a diversity of matter similar to our own.
“An invisible civilisation could be living right under your nose.
“Dark objects or dark life could be very close—but if the dark stuff’s net mass isn’t very big, we wouldn’t have any way to know.
“Even with the most current technology, or any technology that we can currently imagine, only some very specialised possibilities might be testable.
“‘Shadow life,’ exciting as that would be, won’t necessarily have any visible consequences that we would notice, making it a tantalising possibility but one immune to observations. In fairness, dark life is a tall order.“