Can we see a singularity, the most extreme object in the universe?

April 20, 2017
A black hole (on the left) and a naked singularity (on the right). The dashed line represents the event horizon of the black hole, which is absent in the case of a naked singularity, and the arrows represent the direction in which light rays travel. In the case of the black hole, because of the presence of an event horizon, all light rays inside it necessarily end up at the singularity. However, light rays may escape from the vicinity of a naked singularity to a far away observer rendering it visible. Credit: Sudip Bhattacharyya, Pankaj Joshi

A team of scientists at the Tata Institute of Fundamental Research (TIFR), Mumbai, India, have found new ways to detect a bare or naked singularity, the most extreme object in the universe.

When the fuel of a very massive star is spent, it collapses due to its own gravitational pull and eventually becomes a very small region of arbitrarily high matter density, that is a 'Singularity', where the usual laws of physics may breakdown. If this singularity is hidden within an event horizon, which is an invisible closed surface from which nothing, not even light, can escape, then we call this a black hole. In such a case, we cannot see the singularity and we do not need to bother about its effects. But what if the event horizon does not form? In fact, Einstein's theory of general relativity does predict such a possibility when massive stars collapse at the end of their life-cycles. In this case, we are left with the tantalizing option of observing a naked singularity.

An important question then is, how to observationally distinguish a naked singularity from a black hole. Einstein's theory predicts an interesting effect: the fabric of spacetime in the vicinity of any rotating object gets 'twisted' due to this rotation. This effect causes a spin and makes orbits of particles around these astrophysical objects precess. The TIFR team has recently argued that the rate at which a gyroscope precesses (the precession frequency), when placed around a rotating black hole or a naked singularity, could be used to identify this rotating object. Here is a simple way to describe their results. If an astronaut records a gyroscope's precession frequency at two fixed points close to the rotating object, then two possibilities can be seen: (1) the precession frequency of the gyroscope changes by an arbitrarily large amount, that is, there is a wild change in the behaviour of the gyroscope; and (2) the precession frequency changes by a small amount, in a regular well-behaved manner. For the case (1), the rotating object is a black hole, while for the case (2), it is a naked singularity.

The TIFR team, namely, Dr. Chandrachur Chakraborty, Mr. Prashant Kocherlakota, Prof. Sudip Bhattacharyya and Prof. Pankaj Joshi, in collaboration with a Polish team comprising Dr. Mandar Patil and Prof. Andrzej Krolak, has in fact shown that the precession frequency of a gyroscope orbiting a black hole or a naked singularity is sensitive to the presence of an event horizon. A gyroscope circling and approaching the of a black hole from any direction behaves increasingly 'wildly,' that is, it precesses increasingly faster, without a bound. But, in the case of a naked singularity, the precession frequency becomes arbitrarily large only in the equatorial plane, but being regular in all other planes.

The TIFR team has also found that the precession of orbits of matter falling into a rotating black hole or a naked singularity can be used to distinguish these exotic objects. This is because the orbital plane precession frequency increases as the matter approaches a rotating black hole, but this can decrease and even become zero for a rotating naked singularity. This finding could be used to distinguish a naked from a black hole in reality, because the frequencies could be measured in X-ray wavelengths, as the infalling matter radiates X-rays.

Explore further: How fast do black holes spin?

More information: Chandrachur Chakraborty et al, Spin precession in a black hole and naked singularity spacetimes, Physical Review D (2017). DOI: 10.1103/PhysRevD.95.044006

Chandrachur Chakraborty et al. Distinguishing Kerr naked singularities and black holes using the spin precession of a test gyro in strong gravitational fields, Physical Review D (2017). DOI: 10.1103/PhysRevD.95.084024

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RealityCheck
3 / 5 (8) Apr 20, 2017
Note how deeply inculcated has been the UN-REAL, methaphysical, extrapolated-maths NOTION that real objects can undergo 'infinite collapse to singularity' states having no dimensional volume or internal structure (ie, dimensionless point or ring-line of dimensionless points).

It is now obvious that any 'exercise' which relies on such unreal assumptions is doomed to nonsensical conclusions.

Only an analysis treating collapsed objects as REAL, having density/extent parameters and internal/surface structure/properties and effects, can ever get close to understanding the reality of what exists in BH objects (and what may become of such in certain circumstances due to future ambient conditions in the external universal process which produced them in the first place).

The herd-mentality 'peer review' process has 'passed' UN-real, Metaphysical, Big Bang (and other abstract/mathematical model 'myths'); 'graduated' whole generations in the art of myth-based 'thinking/exercises'.
Dingbone
3 / 5 (2) Apr 20, 2017
A gyroscope circling and approaching the event horizon of a black hole from any direction behaves increasingly 'wildly,' that is, it precesses increasingly faster, without a bound
It could be a nice explanation of mechanism of periodical bursts of black holes. It requires to exclude all other possible sources of variable black hole brightness (accretion), i.e. it may be observed only inside mature galaxies, where black holes already consumed available matter in its neighborhood (like the Milky Way).

If the singularity would be naked it would evaporate fast into radiation and we would see it quite clearly like bright object (quasar). IMO the black hole jets can be just the places with weakened event horizons. If they don't allow to see physical surface of black holes directly, they still allow lightweight particles (dark matter, neutrinos) to escape through it.
Dingbone
3 / 5 (2) Apr 20, 2017
Normally the radiation of black hole indicates, that it grows by accretion. The observation of naked singularity would serve as an indicia, that the black hole can evaporate from "inside out" instead. If we want to prove this mechanism, we should focus to changes of black hole brightness in microwave or deep infrared portion of spectrum or with neutrino flux without visible changes of brightness (which just follow an accretion).

There are also indirect options, how to spot such a bursts, because the jets of escaping neutrinos would interact with microwave background into traces of X-rays, which would be detected outside the black hole at distance in the galactic halo. IMO Planck X-ray spaceprobe could detect the traces of such jets around MilkyWay already. Such a traces could be formed also by accretion - so that they cannot serve as a conclusive evidence of black hole "flashing" by itself.
Benni
1.8 / 5 (4) Apr 20, 2017
Dr. Mandar Patil and Prof. Andrzej Krolak, has in fact shown that the precession frequency of a gyroscope orbiting a black hole or a naked singularity is sensitive to the presence of an event horizon. A gyroscope circling and approaching the event horizon of a black hole from any direction behaves increasingly 'wildly,' that is, it precesses increasingly faster


Why is it that this is the first news we hear about these two putting a gyroscope in orbit around a BH? I would have thought the voyage of this probe to place this gyroscope in proximity to a BH would have made major headlines. Where was this BH located ?
cantdrive85
3 / 5 (6) Apr 20, 2017
Where was this BH located?

Only in the fanciful imagings of the pseudoscientific maths "wizards".
cantdrive85
3.4 / 5 (5) Apr 20, 2017
it collapses due to its own gravitational pull and eventually becomes a very small region of arbitrarily high matter density, that is a 'Singularity', where the usual laws of physics may breakdown.

LOL! An abomination of physics and reality.
Seeker2
3 / 5 (2) Apr 22, 2017
Our title:

"Can we see a singularity, the most extreme object in the universe?"

Well I don't think there is anything there to see. There was at one time, but its energy density has been returned to the dark energy. This happens when the dark energy density exceeds the energy density required to create the particle. The particle essentially dissolves. Then there is no gradient in the dark energy and hence no gravity. Working on it.
nikola_milovic_378
1 / 5 (1) Apr 22, 2017
This is evidence that science, until today, did not understand the structure of the universe. It was a miracle that no one science does not attempt to explore the true causes of the matter, a practice for decades to find the "God particle", but none of them does not believe in the existence of God. Well, when they formed in such a form that they can explore, even that which God alone can form.
A black hole is "graves" material, where the material is transformed up in ether, from which it is derived. This can be considered a naked singularity. And the other part, a star, dying, it is part of a series of processes of forming substance, when this is of the star, the dissolution of the same, form a cloud of the heavenly bodies from the gas obtained after the "death" of these stars (neutron star). Could scientists to move this through research organization of the universe and will be on the right path If you do not know, we can solve together !!!!

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