Last year, the astronomical community achieved an absolute surprise. For the first time, the world has collectively looked at the real picture of the shadow of a black hole. It was a great achievement in terms of completion of many years of work, both human cooperation and technical skills.
And, like the best scientific breakthroughs, it opened up a whole new world of exploration. For a team led by astronomer Hector Olivers from Redwood University in the Netherlands and Goethe University in Germany, the quest was: How do we do it? I know M87 * A black hole?
“While the picture is consistent with our expectations of what the black hole will look like, it’s important to make sure that what we’re seeing really feels right to us,” Olivers told Science Alert.
“Similarly in black holes, boson stars are predicted by general relativity and are able to reach millions of solar masses and reach very high concentrations. They share these features with supermassive blackholes. Objects can actually be boson stars.
Thus, in a new study, Oliver and his team calculated how a boson star could look through our telescopes and how it differed from a direct image of a raised black hole.
Boson stars are one of the most amazing theoretical objects out there. These are not like conventional stars, they are the subject of a substance other than these. But where the stars are basically made up of particles called fermions – protons, neutrons, electrons, which make up a more significant part of our universe – boson stars were formed entirely by bosons.
These particles – including photons, gluons and the famous Higgs boson – do not follow physical laws like fermions.
Fermins are subject to the Pauli exclusion principle, which means you cannot have two identical particles occupying the same space. Bosons can, of course, be superposed; When they combine, they act like a large particle or matter wave. We know this because it was made in a laboratory, which we call the Bose-Einstein condensate.
In the case of boson stars, the particles can be enclosed in a space that can be described by individual values, or points on scales. Given the right type of boson in the right format, this ‘scalar field’ can be read in a relatively stable format.
This is theory, at least. Not that anyone has seen one in action. Bosons with the mass required to form such a structure should be left alone with the mass of a supermassive black hole, yet not spotted.
If we could identify any boson stars, we would effectively locate these elusive particles.
“In order to form a larger structure for SMBH examinees, boson masses need to be very small (less than 10).-17 Electronvolts), ”Olivers said.
“Spin-0 bosons with similar or smaller masses appear in different cosmic models and string theories and have been proposed as dark matter candidates under different names (Scalar Field Dark Matter, Ultra-Light Action, Fuzzy Dark Matter, Quantum Wave Dark Matter).” National hypotheses will be extremely difficult to identify, but observation of an object that looks like a boson star will indicate their existence. “
Boson stars do not fuse the nucleus and they cannot emit any radiation. They just want to disappear and sit in space. Much like a black hole.
Unlike black holes, boson stars will be transparent – they lack an absorbent surface that stops photons or they have no event horizon. Photons can escape boson stars, although their path may be slightly curved by gravity.
However, some boson stars may have a plasma rotating ring around them – much like a disk lining a black hole. And it looks pretty much the same, like a shiny donut with a dark zone inside.
Thus, Olivers and his team served simulations of the dynamics of these plasma rings and compared them to what we can expect from a black hole.
“The plasma configuration we use is not set up ‘by hand’ (under reasonable assumptions), but results from simulations of plasma dynamics. This allows plasma to evolve over time and form structures like nature,” Olivers explained.
“Thus we were able to relate the size of the dark region of the boson star image (which mimics the shadow of a black hole) to the radius where the plasma instability stops. And it allows us to predict its size for other boson wires that we did not emulate. “
They found that the shadow of a boson star would be significantly smaller than the shadow of a black hole of similar mass. Thus, the team rejects M ৮87 * * as a boson star – the mass of the object is inferred from the rotational velocity of the gas around it, and the shadow is so large that the mass can be produced by boson stars.
However, the team also considered the technical capabilities and limitations of the Event Horizon Telescope that provided the first image of that black hole; They deliberately set about visualizing their results because they thought the boson stars would be seen as illustrated by EHT.
This means that their results can be compared with future EHT observations to determine if what we are seeing is actually a supermassive black hole.
If it doesn’t, it will be a very big deal. This does not mean that supermassive black holes do not exist – the range of people for black holes is too wide for boson stars. This, however, would indicate that boson stars are real and could have a far-reaching effect instead, for everything from inflation in the early universe to the search for darkness.
“This would mean that cosmic structural fields exist and play an important role in shaping structures in the universe,” Oliver told Science Alert.
“The rise of supermassive black holes is still not very well understood, and if it turns out that at least some of the candidates are actually boson stars, we need to think about the different formation processes involved in the scalar case.”
The study was published in July Monthly Notice of the Royal Astronomical Society.