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Comment by zmgsabst | Hacker News Reader

Are these “frozen” quasar anyons?

Nobody has ever addressed my question about how the braiding you’d expect to form in a quasar would unwind — and if it doesn’t, we should expect to find most structures along “cooled, inflated” braiding. Which we seem to.

> Explained in a colloquial manner, the extended objects (loop, string, or membrane, etc.) can be potentially anyonic in 3+1 and higher spacetime dimensions in the long-range entangled systems.

https://en.wikipedia.org/wiki/Anyon

In particular, the “loops” would be magnetic field lines from the singularity to the disc (and back), which would become tangled via swirls within the disc as it spiraled inwards. While each piece would be small, the total braid would be quite large — due to number of particles and chaotic nature of the disc.

I know a single anyon doesn’t weigh much - but is there an estimate of “anyonic mass” to the galaxy, stores as tangles?

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> Nobody has ever addressed my question

Ok, I will try. I have to admit I do not fully understand what you are asking.

As noted in the link at the top, it is reasonable to speculate that these filaments are related to the activity of the galactic centre supermassive black hole. However, we do not have a quasar in our galaxy, and it is hard to imagine (consistent with evidence from this and similar galaxies at various cosmological redshifts) that the Milky Way possessed an active galactic centre which subsequently was quenched. Indeed, part of the mystery here is that there is a quite weak magnetic field permeating the galactic centre, and little outward cosmic ray pressure.

The spectral index (more details at https://arxiv.org/abs/2201.10552 §3.1, "nonthermal radio filaments that have broad spectral index distribution as well as the steepest spectral index that can readily be discerned at high latitudes", cf https://en.wikipedia.org/wiki/Spectral_index although neither link is especially friendly to non-experts) is entirely consistent with synchrotron radiation, which does not require any exotic particles at the filamentary sources of the radio emissions. As discussed in §3.2 of the arxiv preprint, all we need is highly accelerated electrons. The mechanism for accelerating the electrons is unknown, but there are several explanations available that do not require exotic particles. §4.3 discusses several plausible alternatives.

I'm no expert on anyons but I do know how Wilczek described them when he first proposed them, and Keilmann's observations of his humour, and I struggle to see what problems introducing anyons might reasonably solve at these bulk scales. Additionally, I do not see how anyonic behaviour -- rather than straightforward magnetobremsstrahlung -- could be relevant, much less a better description, at the warm temperatures in the environments of these filaments and galactic centre molecular clouds.

Unfortunately, I don't understand your second last paragraph at all.

Wait, how do we get the Fermi bubbles without a period of active galactic centre? Or do you mean that there's been no large scale jets from our SMBH?

"Quasar" goes to luminosity, and our galaxy could never have been as luminous as any quasar we know of without some mechanism to totally block fast (matter) outflows and another to block the quenching of star formation from the negative feedback of a highly luminous galactic centre.

Our central black hole is very quiet (as opposed to active), at least a dozen orders of magnitude below the Eddington luminosity in X-rays. Quasars are at (or a very large percentage of) the Eddington luminosity, almost certainly for at least Gyr durations.

The Fermi bubbles are interesting, but around luminous AGNs (at all redshifts) we tend to find extended outflows in ionized ("hibals") and molecular gasses, and afaik we don't see anything like that associated with those gammas. AFAIR there is also a missing ~ 1250 angstrom restframe peak and an associated relativistic wind's redshift (0.1-0.2 c or 30-60 Mm/s) leading to line driving. About a decade ago there was a fair amount of discussion about the Fermi bubbles as evidence of a (not so high) luminosity AGN jet, but it seemed to require contrivances to drop in a sufficiently massive molecular cloud (~ 10^5 solar masses around 10^7 years ago, but don't quote me, not my speciality, and I was already convinced about the present << quasar luminosity (and no trace of tremendous variability or eruptive phase up to considerably more than a few percent of the Eddington luminosity) and by the stellar population).

I appreciate the reply, but I think we’re slightly talking past each other in that you’re discussing anyons as a source of the emissions from the structure, while I’m saying that the emissions are from a classical source aligned to an anyon — the overall structure the radiant gases you’re describing are attracted to, and source of filament shape. That the emissions match synchrotron radiation doesn’t distinguish, in that we’d expect electrons flowing along/around a loop excitation to emit precisely that, right?

I would say that galactic anyons solve a problem:

The toroidal knotting you’d expect around some kind of active black hole would produce effects we see, and connects them via the same mechanism —

1. Why galaxies have weird filament structures everywhere — gas is settling into loop excitations around the black hole;

2. Which is also why the galaxy seems unusually bound, because pulling it apart places additional strain in many, many anyons we can’t see or readily interact with (due to scale);

3. While also explaining the same features at a higher scale, eg galactic clusters or why so many things like Great Attractor look like the intersection of a toroidal knot.

My last paragraph is that it’s my understanding some tiny amount of energy goes into being the anyon, and hence it has mass. So the “braiding” of any system would contribute a (small?) mass to it — and I wanted to see the calculation.

I assume I’m off on a wild chase, but I want to see where the math fails for my own education.

I'm afraid I'm not much more clued-in now about what you're thinking. I'll try my best.

> ... "braiding" of any system would contribute a (small?) mass to it -- and I wanted to see the calculation

My best guess is that you are thinking that the (far from active) black hole in the central parsec of our galaxy is somehow lifting mass out of itself and into the wider galaxy, and so will briefly discuss that.

A reasonable first step towards the theoretical footing behind that is Murata & Soda 2006, in Phys. Rev. D. https://journals.aps.org/prd/abstract/10.1103/PhysRevD.74.04..., "Hawking radiation from rotating black holes and gravitational anomalies" (also at https://arxiv.org/abs/hep-th/0606069v2) where the scalar field (also seen in Hawking 1978) is literally a form of "anyon" field. I don't see how the use of the name "anyon" helps, however, and the outward flux is going to be small -- even very very small compared to the ordinary thermal collisions of gas and dust in the galaxy centre, let alone the stars there.

I think that means you're on course for an extension to the Standard Model of Particle Physics to add in some electromagnetically-non-interacting species that decays at some distance into electromagnetically-interacting ones, along the lines of various dark matter decay models, especially those designed to produce "feedback" in spite of quiet galactic centres. I don't think this is likely to bear fruit, but cf. this blog on DM->tau decay: http://honorsfellows.blogs.wm.edu/2011/06/12/decaying-dark-m...

> I assume I'm off on a wild chase, but I want to see where the math fails for my own education.

I'm afraid I can't join you on your chase, wild or not, but I think that the mathematics of black holes is reasonably accessible and easy enough to find in a variety of textbooks. Coupling an anyon field to it is an exercise in quantum field theory on curved spacetime (as in Murata & Soda) or perhaps a second-quantization of an electrovac solution based on Kerr-Newman. I'm really struggling to see how -- given the high temperatures and high particle numbers involved -- anything is to be gained by looking at the truly microscopic behaviour of the stress-energy tensor, even in the very near region of the horizon. I'm also struggling to see how such effects relating to our central black hole are not totally washed out by processes in the bulge or in the thin disc. Our central black hole is not only far from active, it is also quite small compared to the black holes we find in other galaxies, especially Seyferts and recently discovered high-redshift (z ~ 7.6) QSOs. There is also a lot of dust and gas along our line of sight to the galactic centre, and between these filamentary structures and the galactic centre. (A number of these filaments are much closer to known radio-bright supernova remnants, as detailed in the study, but don't seem very different from those far from known SNRs.) There is also no evidence for beyond-the-standard-model(-of-particle-physics) physics in the discovery of these filaments. I don't mind being asked to think about BTSM, but these filaments are a very poor justification for that.

Finally, the only knotting I expect around a quasar or microquasar are bright spots in the plasma of jets consistent with small-angle radiation, and it's hard to think of a better explanation than proper motion of the source. We see this in stellar-mass X-Ray binaries (especially nearby microquasars), for example. The absence in extragalactic quasars supports this idea, since the proper motion of those sources will necessarily be lower than galactic ones by a couple orders of magnitude.

> I want to see where the math fails for my own education

If you care to write down some math now, I promise to at least have a look at it and see if I can aim you at some additional resources which may be more helpful still.

I’m asking for resources on the toroidal knotting of the large scale EM around black holes, both nearby in the immediate accretion disk and from the perspective of the galaxy as a whole.

Those knots are (supermacro) anyons, because they’re tangles in a field that form particle-like excitations, though in this case loop like excitations. And what we’re seeing as weird patterns is gas dancing around those loop excitations within the galaxy, eg emitting synchrotron radiation as they do.

That would be one explanation of why we find so many filaments perpendicular to the galactic plane.

> I'm really struggling to see how -- given the high temperatures and high particle numbers involved -- anything is to be gained by looking at the truly microscopic behaviour of the stress-energy tensor, even in the very near region of the horizon.

For the same reason that braiding tells us something about the behavior of plasma globes — the topology doesn’t just “go away”, and we need to account for where the tangle went. It either fell into the black hole or it’s still here. For the same reason plasma globe filaments only collapse at topological defects.

The precise reason that I think that we can’t ignore the braiding term is that we’re forming an entanglement structure between all of those particles — and while it’s a jumbled mess, that’s precisely why we can’t ignore its contribution to mass and galactic binding.

I also would point out that this doesn’t require any extensions to the standard model — I’m just saying something that happens small also happens big: that braiding is a fact of the wave equation.

> I’m just saying something that happens small also happens big: that braiding is a fact of the wave equation

There are multiple sources in the galaxy, so on purely a Gauss Law analysis I am pretty sure you are barking up the wrong tree.

Additionally,

> [the] Great Attractor look[s] like the intersection of a toroidal knot

What? Please explain.

> the galaxy seems unusually bound

Discovered features of our galaxy is about the best evidence for Copernicanism that we have. Up to the limit of current observation, there is nothing at all physically special about the Milky Way for any practical purposes.

We would therefore expect to find filamentary structures in other spiral galaxies in our sky, and be surprised (which is great for theorists) if they were not there when we look.

What do you mean by pulling our galaxy apart? What's the mechanism?

Here is where you should write down the maths you are hoping someone will check, and here is where you get to satisfy your complaint that nobody has ever answered you seriously before.

In particular, and please forgive me that I can't think of a politer way of putting it, I think you need to demonstrate that you have any idea at all about what you are talking about in your numbered paragraphs in this reply-comment's parent.

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