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Weird 'gravitational molecules' could orbit black holes like electrons swirling around atoms

This computer simulation shows supermassive black holes only 40 orbits from merging.
This computer simulation shows supermassive black holes only 40 orbits from merging.
(Image: © NASA's Goddard Space Flight Center)

Black holes are notable for many things, especially their simplicity. They're just … holes. That are "black." This simplicity allows us to draw surprising parallels between black holes and other branches of physics. For example, a team of researchers has shown that a special kind of particle can exist around a pair of black holes in a similar way as an electron can exist around a pair of hydrogen atoms — the first example of a "gravitational molecule." This strange object may give us hints to the identity of dark matter and the ultimate nature of space-time.

Ploughing the field

To understand how the new research, which was published in September to the preprint database arXiv, explains the existence of a gravitational molecule, we first need to explore one of the most fundamental –- and yet sadly almost never talked about –- aspects of modern physics: the field.

Related: The 12 strangest objects in the universe

A field is a mathematical tool that tells you what you might expect to find as you travel from place to place in the universe. For example, if you've ever seen a TV weather report of temperatures in your local area, you're looking at a viewer-friendly representation of a field: As you travel around your town or state, you'll know what kind of temperatures you're likely to find, and where (and whether you need to bring a jacket).

This kind of field is known as a "scalar" field, because "scalar" is the fancy mathematical way of saying "just a single number." There are other kinds of fields out there in physics-land, like "vector" fields and "tensor" fields, which provide more than one number for every location in space-time. (For example, if you see a map of wind speed and direction splashed on your screen, you're looking at a vector field.) But for the purposes of this research paper, we only need to know about the scalar kind.

The atomic power couple

In the heydays of the mid-20th century, physicists took the concept of the field — which had been around for centuries at that point, and was absolutely old-hat to the mathematicians — and went to town with it.

They realized that fields aren't just handy mathematical gimmicks — they actually describe something super-fundamental about the inner workings of reality. They discovered, basically, that everything in the universe is really a field.

Related: The 11 most beautiful mathematical equations

Take the humble electron. We know from quantum mechanics that it's pretty tough to pin down exactly where an electron is at any given moment . When quantum mechanics first emerged, this was a pretty nasty mess to understand and untangle, until the field came along.

In modern physics, we represent the electron as a field — a mathematical object that tells us where we're likely to spot the electron the next time we look. This field reacts to the world around it — say, because of the electric influence of a nearby atomic nucleus — and modifies itself to change where we ought to see the electron.

The end result is that electrons can appear only in certain regions around an atomic nucleus, giving rise to the entire field of chemistry (I'm simplifying a bit, but you get my point). 

Black hole buddies

And now the black hole part. In atomic physics, you can completely describe an elementary particle (like an electron) in terms of three numbers: its mass, its spin and its electric charge. And in gravitational physics, you can completely describe a black hole in terms of three numbers: its mass, its spin and its electron charge.

Coincidence? The jury's out on that one, but for the time being we can exploit that similarity to better understand black holes.

In the jargon-filled language of particle physics that we just explored, you can describe an atom as a tiny nucleus surrounded by the electron field. That electron field responds to the presence of the nucleus, and allows the electron to appear only in certain regions. The same is true for electrons around two nuclei, for example in a diatomic molecule like hydrogen (H2.)

You can describe the environment of a black hole similarly. Imagine the tiny singularity at a black heart somewhat akin to the nucleus of an atom, while the surrounding environment — a generic scalar field — is similar to the one that describes a subatomic particle. That scalar field responds to the presence of the black hole, and allows its corresponding particle to appear only in certain regions. And just as in diatomic molecules, you can also describe scalar fields around two black holes, like in a binary black hole system.

The authors of the study found that scalar fields can indeed exist around binary black holes. What's more, they can form themselves into certain patterns that resemble how electron fields arrange themselves in molecules. So, the behavior of scalar fields in that scenario mimics how electrons behave in diatomic molecules, hence the moniker "gravitational molecules."

Why the interest in scalar fields? Well for one, we don't understand the nature of dark matter or dark energy, and it's possible both dark energy and dark matter could be made up of one or more scalar fields), just like electrons are made up of the electron field.

If dark matter is indeed composed of some sort of scalar field, then this result means that dark matter would exist in a very strange state around binary black holes — the mysterious dark particles would have to exist in very specific orbits, just like electrons do in atoms. But binary black holes don't last forever; they emit gravitational radiation and eventually collide and coalesce into a single black hole. These dark matter scalar fields would affect any gravitational waves emitted during such collisions, because they would filter, deflect and reshape any waves passing through regions of increased dark matter density. This means we might be able to detect this kind of dark matter with enough sensitivity in existing gravitational wave detectors.

In short: We soon might be able to confirm the existence of gravitational molecules, and through that open a window into the hidden dark sector of our cosmos.

Originally published on Live Science.

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  • rod
    The arXiv paper cited, https://arxiv.org/pdf/2010.00008.pdf, has 4 references to DM, ultra light DM. Recent searches for ultra light DM came up short in the local area, https://phys.org/news/2020-11-advanced-atomic-clock-dark-detector.html
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  • Stephen J. Bauer
    Every closer to my theoretical concept for an alternative perspective of the universe. A little known team of researchers has shown that a special kind of "particle" can exist around a pair of black holes , and they introduce it as the first example of a "gravitational molecule." What's more, these proposed "gravitational molecules" can form themselves into certain patterns that resemble how electron fields arrange themselves in molecules. The authors of this study want to demonstrate that evidence to support "scalar fields" may indeed exist around binary black holes in a behavior similar of scalar fields in that scenario mimics how electrons behave in diatomic molecules. Furthermore, it is this team of researchers belief that these gravitational molecules respond within the presence of the black hole, allowing its corresponding particle to appear only in certain regions or orbits - as understood of "scalar fields." And just as in diatomic molecules, they intend to describe "scalar fields" around two black holes, like in a binary black hole system.

    Subsequently this strange process may give us hints to the identity of dark matter and the ultimate nature of space-time. If dark matter is indeed composed of some sort of scalar field, then this result means that dark matter would exist in a very strange state around binary black holes — the mysterious dark particles would have to exist in very specific orbits, just like electrons do in atoms. But binary black holes don't last forever; they emit gravitational radiation and eventually collide and coalesce into a single black hole. These dark matter scalar fields would affect any gravitational waves emitted during such collisions, because they would filter, deflect and reshape any waves passing through regions of increased dark matter density. This means we might be able to detect this kind of dark matter with enough sensitivity in existing gravitational wave detectors. In short: We soon might be able to confirm the existence of gravitational molecules, and through that open a window into the hidden dark sector of our cosmos.

    Why do I see this as promising? It has been the subject of my research that dark matter is this gravitational potential, and that the creation of matter as a whole is ultimately the inducement of a complementary displacement, or warping, in the dark energy medium of the space-time fabric. And within this warping, there is yet another perturbation in the whole matter created; a dual relationship of newly created positive density matter in an envelopment of negative density matter. The complementary displacement insulates the newly created positive density matter in an envelopment of negative density matter. This envelope of negative density matter, known as dark matter, then infiltrates the spaces in matter, providing it with the ability to interact, bond, and evolve.

    For me it is not all surprising that both the concepts of dark matter and gravity defy all attempts to be identified as a particle, because I see them as one and the same. The only way that a black hole could work is by thinking about gravity a bit differently. In fact, one actually has to re-imagine the universe from its perspective make up. Considering the current notion the standard model of cosmology, the current measurements decompose the total energy of the observable universe with approximately 68% dark energy, 27% mass–energy via dark matter, and 5% mass-energy via ordinary matter. In which case, as black holes are significantly more energy dense than ordinary matter, it would then make more sense that black holes are a product of dark matter rather than condensed ordinary matter. This requires that we rethink these internal relationships for total energy.

    If I apply the concepts this proposed theory for "gravitational molecules" I can surmise that a graviton is meant to be the smaller constituent part of such gravitational molecules. The basic problem with such research is trying to identify dark matter as a particle. It is the same problem that physicists have had with trying to identify gravity as a particle, but not without trying. In theories of quantum gravity, the graviton is the hypothetical quantum of gravity, an elementary particle that mediates the force of gravity. There is no complete quantum field theory of gravitons due to an outstanding mathematical problem with re-normalization in general relativity.

    Like the hypothetical graviton, dark matter density mirrors that of ordinary matter density; in effect, negative mass density and positive mass density. And even though ordinary matter (positive mass density) reveals its coherency in particle form upon detection, dark matter (negative mass density) does not. In which case it would then follow that dark matter can be accumulated, separate of ordinary matter. It would therefore also follow that the gravitational force is more representative of negative density mass than positive density mass. Therefore it would not be a great leap of imagination to view the notion of black holes as made up only of dark matter.

    Example: Upon this hypothesis then, one can expect that there is a require transition to separate ordinary matter from its complementary dark matter upon the event horizon of a black hole. It starts first with the disintegration of matter, as a whole, as it interacts with the event horizon of the black hole. As the positive density mass is 'squeezed' upon its own gravitational acceleration toward the black hole, liken to the spaghettification effect, its matter changes to allow for its disintegration via transmutation and the massive release of photons due to alpha decay and beta decay. This is the effect wherein positive density mass is collected within the event horizon, into a plasma, increasing its photon density. This 'squeezing' effect is like extracting out the dark matter from the whole matter, allowing for the ordinary matter to be reduced to its smallest constituent components. The dark matter is then absorbed into the black hole, and the remnants of ordinary matter are discarded and radiated out at high velocity back into the cosmos; to start, once again, to reintegrate into the universe via bonding and evolving.

    If you're interested in exploring this concept more, please review the alternative theories presented in the book, 'The Evolutioning of Creation: Volume 2', or even the ramifications of these concepts in the sci-fi fantasy adventure, 'Shadow-Forge Revelations'.
    https://www.space.com/black-holes-gravitational-molecules-evidence
    Reply
  • rod
    Post #3 presents some interesting info on DM. Other reports like this, 'Searching for axion dark matter conversion signals in the magnetic fields around neutron stars', https://phys.org/news/2020-11-axion-dark-conversion-magnetic-fields.html, and the paper at 'Green Bank and Effelsberg Radio Telescope Searches for Axion Dark Matter Conversion in Neutron Star Magnetospheres', https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.171301, “ABSTRACT Axion dark matter (DM) may convert to radio-frequency electromagnetic radiation in the strong magnetic fields around neutron stars. The radio signature of such a process would be an ultranarrow spectral peak at a frequency determined by the mass of the axion particle..."

    My observation. The NASA ADS Abstract is 'Green Bank and Effelsberg Radio Telescope Searches for Axion Dark Matter Conversion in Neutron Star Magnetospheres', https://ui.adsabs.harvard.edu/abs/2020PhRvL.125q1301F/abstract, October 2020. arXiv paper attached. The arXiv paper shows the reported distance for the two neutron stars studied, "We take RX J0806.4−4123 and RX J0720.4−3125 to be at distances of 250 pc and 360 pc from Earth, respectively ."

    So far, searches for various DM particles or DM candidates continue to come up short in the detection efforts. As the paper abstract begins, "Axion dark matter (DM) may convert to radio-frequency electromagnetic radiation in the strong magnetic fields around neutron stars. The radio signature of such a process would be an ultranarrow spectral peak at a frequency determined by the mass of the axion particle."

    This study using the two neutron stars cited did not find the axions. The paper has 18 references to 'dark matter', 139 references to 'axion', 13 references to 'axions', and 1 reference to 'wimp' DM searches.]
    Reply