Dark matter could be forging strange cold stars in deep space – and they may be responsible for a recent spate of ‘alien’ signals picked up on Earth.
The elusive material – which makes up 80 per cent of our universe but has never been observed – could be clumping together into ‘cold stars’, a study suggests.
These stars may be behind the mysterious ‘fast radio bursts’ detected by radio astronomers across the globe.
Currently, these strange signals have no known source, and some had suggested they were messages sent by extraterrestrials.
Dark matter could be forging strange cold stars in deep space – and they may be responsible for a recent spate of ‘alien’ signals picked up on Earth (stock image)
The research comes from a team of scientists at the Institute for Nuclear Research of the Russian Academy of Sciences in Moscow.
Their computer models simulated how dark matter may interact around the edges of dwarf galaxies – the smallest galaxies in the known universe.
‘In our work, we simulated the motion of a quantum gas of light, gravitationally interacting dark matter particles,’ said study lead author Dmitry Levkov.
The simulations showed that dark matter may clump together into cold, unseen ‘Bose stars’ within a galaxy’s halo – the ring of gas and dust around its outer edge.
Dark matter is a hypothetical substance said to make up roughly 27 per cent of the universe.
The enigmatic material is invisible because it does not reflect light, and has never been directly observed by scientists.
It is thought the material can clump together into something called a Bose-Einstein condensate.
Scientists suggest gas particles around dwarf galaxies mix to produce invisible ‘cold stars’. Pictured left is a simulation of the initial moment of this process, when the gas is mixed. Right shows the moment shortly after the formation of a Bose star. The colour indicates density: White-blue-green-yellow, from sparse to dense
WHAT IS DARK MATTER?
Dark matter is a hypothetical substance said to make up roughly 27 per cent of the universe.
The enigmatic material is invisible because it does not reflect light, and has never been directly observed by scientists.
Astronomers know it to be out there because of its gravitational effects on known matter.
The European Space Agency says: ‘Shine a torch in a completely dark room, and you will see only what the torch illuminates.
Dark matter is a hypothetical substance said to make up roughly 27 per cent of the universe. It is thought to be the gravitational ‘glue’ that holds the galaxies together (artist’s impression)
‘That does not mean that the room around you does not exist.
‘Similarly we know dark matter exists but have never observed it directly.’
The material is thought to be the gravitational ‘glue’ that holds the galaxies together.
Calculations show that many galaxies would be torn apart instead of rotating if they weren’t held together by a large amount of dark matter.
Just five per cent the observable universe consists of known matter such as atoms and subatomic particles.
When temperatures sit just above absolute zero, quantum particles lose the energy to mix and wobble, leaving behind a uniform dark ‘slush’.
Individual quantum particles become uniform and clouds of them are drawn together by gravity to form superfluids.
The new study suggests Bose-Einstein condensate forms in the halos of dark galaxies, and they could form in a timespan shorter than the lifetime of the universe.
If they exist, Bose stars may be responsible for mysterious signals known as Fast Radio Bursts that have baffled scientists for decades.
WHAT ARE FAST RADIO BURSTS AND WHY DO WE STUDY THEM?
Fast radio bursts, or FRBs, are radio emissions that appear temporarily and randomly, making them not only hard to find, but also hard to study.
The mystery stems from the fact it is not known what could produce such a short and sharp burst.
This has led some to speculate they could be anything from stars colliding to artificially created messages.
Scientists searching for fast radio bursts (FRBs) that some believe may be signals sent from aliens may be happening every second. The blue points in this artist’s impression of the filamentary structure of galaxies are signals from FRBs
The first FRB was spotted, or rather ‘heard’ by radio telescopes, back in 2001 but wasn’t discovered until 2007 when scientists were analysing archival data.
But it was so temporary and seemingly random that it took years for astronomers to agree it wasn’t a glitch in one of the telescope’s instruments.
Researchers from the Harvard-Smithsonian Center for Astrophysics point out that FRBs can be used to study the structure and evolution of the universe whether or not their origin is fully understood.
A large population of faraway FRBs could act as probes of material across gigantic distances.
This intervening material blurs the signal from the cosmic microwave background (CMB), the left over radiation from the Big Bang.
A careful study of this intervening material should give an improved understanding of basic cosmic constituents, such as the relative amounts of ordinary matter, dark matter and dark energy, which affect how rapidly the universe is expanding.
FRBs can also be used to trace what broke down the ‘fog’ of hydrogen atoms that pervaded the early universe into free electrons and protons, when temperatures cooled down after the Big Bang.
According to the scientists, dark mark can interact with electromagnetic fields and decay into radiophotons.
These then travel billions of miles where they are picked up by sensitive equipment on Earth.
‘This effect is vanishingly small, but inside the Bose star, it may be resonantly amplified, as in a laser, and could lead to giant radio bursts,’ they said.
For now, the team is looking for a way to detect and quantify these invisible stars.
‘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,’ Dr Levkov said.