Milky Way’s central black hole could be a ball of dark matter

Like most galaxies, the Milky Way is thought to host a supermassive black hole in its center – but perhaps its dark heart is made of different stuff. A new study proposes that it could instead be a dense core of dark matter, made up of hypothetical particles called “darkinos.”

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Interesting, ta.

>hypothetical particles called “darkinos.”

Sounds vaguely racist.

Bubblecar said:

Interesting, ta.

>hypothetical particles called “darkinos.”

Sounds vaguely racist.

so what then are black holes?

roughbarked said:

Bubblecar said:

Interesting, ta.

>hypothetical particles called “darkinos.”

Sounds vaguely racist.

so what then are black holes?

Agujero negro

dv said:

roughbarked said:

Bubblecar said:

Interesting, ta.

>hypothetical particles called “darkinos.”

Sounds vaguely racist.

so what then are black holes?

Agujero negro

:)

Nah,

From the very beginning, there have been people who don’t believe in black holes, it’s become something of a religious cult to deny the existence of singularities.

But electrons are singularities, so wake up.

mollwollfumble said:

Nah,

From the very beginning, there have been people who don’t believe in black holes, it’s become something of a religious cult to deny the existence of singularities.

But electrons are singularities, so wake up.

Really? Tell me more.

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

In physics, there is a speculative hypothesis that if there were a black hole with the same mass, charge and angular momentum as an electron, it would share other properties of the electron. Most notably, Brandon Carter showed in 1968 that the magnetic moment of such an object would match that of an electron. This is interesting because calculations ignoring special relativity and treating the electron as a small rotating sphere of charge give a magnetic moment that is off by roughly a factor of 2, the so-called gyromagnetic ratio.

However, Carter’s calculations also show that a would-be black hole with these parameters would be ‘super-extremal’. Thus, unlike a true black hole, this object would display a naked singularity, meaning a singularity in spacetime not hidden behind an event horizon. It would also give rise to closed timelike curves.

Standard quantum electrodynamics (QED), currently the most comprehensive theory of particles, treats the electron as a point particle. There is no evidence that the electron is a black hole (or naked singularity). Furthermore, since the electron is quantum mechanical in nature, any description purely in terms of general relativity is inadequate. Hence, the existence of a black hole electron remains strictly hypothetical

transition said:

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

In physics, there is a speculative hypothesis that if there were a black hole with the same mass, charge and angular momentum as an electron, it would share other properties of the electron. Most notably, Brandon Carter showed in 1968 that the magnetic moment of such an object would match that of an electron. This is interesting because calculations ignoring special relativity and treating the electron as a small rotating sphere of charge give a magnetic moment that is off by roughly a factor of 2, the so-called gyromagnetic ratio.

However, Carter’s calculations also show that a would-be black hole with these parameters would be ‘super-extremal’. Thus, unlike a true black hole, this object would display a naked singularity, meaning a singularity in spacetime not hidden behind an event horizon. It would also give rise to closed timelike curves.

Standard quantum electrodynamics (QED), currently the most comprehensive theory of particles, treats the electron as a point particle. There is no evidence that the electron is a black hole (or naked singularity). Furthermore, since the electron is quantum mechanical in nature, any description purely in terms of general relativity is inadequate. Hence, the existence of a black hole electron remains strictly hypothetical

Thank you transition. That’s more than I wanted to say. Yes, a “naked singularity” fits the bill.

An electron has the properties of mass, charge and spin, and is a point-like particle.
A black hole has the properties of mass, charge and spin, and is a point-like particle.
An electron has a classical radius, but obects can approach closer than the classical radius (hence like a naked singularity), its radius in quantum mechanics is exactly zero. Finite mass in zero radius makes a black hole, doesn’t it.

A gravitational singularity, spacetime singularity or simply singularity is a location in spacetime where the density and gravitational field of a celestial body is predicted to become infinite by general relativity in a way that does not depend on the coordinate system. The quantities used to measure gravitational field strength are the scalar invariant curvatures of spacetime, which includes a measure of the density of matter. Since such quantities become infinite at the singularity point, the laws of normal spacetime break down.

wiki

mollwollfumble said:

Nah,

From the very beginning, there have been people who don’t believe in black holes, it’s become something of a religious cult to deny the existence of singularities.

But electrons are singularities, so wake up.

Sigh

What makes you think electrons are singularities?

And black holes can exist without singularities.

The Rev Dodgson said:

mollwollfumble said:

Nah,

From the very beginning, there have been people who don’t believe in black holes, it’s become something of a religious cult to deny the existence of singularities.

But electrons are singularities, so wake up.

Sigh

What makes you think electrons are singularities?

And black holes can exist without singularities.

I mean it makes GR a lot simpler if fundamental particles are taken to be pointlike…

mollwollfumble said:

transition said:

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

In physics, there is a speculative hypothesis that if there were a black hole with the same mass, charge and angular momentum as an electron, it would share other properties of the electron. Most notably, Brandon Carter showed in 1968 that the magnetic moment of such an object would match that of an electron. This is interesting because calculations ignoring special relativity and treating the electron as a small rotating sphere of charge give a magnetic moment that is off by roughly a factor of 2, the so-called gyromagnetic ratio.

However, Carter’s calculations also show that a would-be black hole with these parameters would be ‘super-extremal’. Thus, unlike a true black hole, this object would display a naked singularity, meaning a singularity in spacetime not hidden behind an event horizon. It would also give rise to closed timelike curves.

Standard quantum electrodynamics (QED), currently the most comprehensive theory of particles, treats the electron as a point particle. There is no evidence that the electron is a black hole (or naked singularity). Furthermore, since the electron is quantum mechanical in nature, any description purely in terms of general relativity is inadequate. Hence, the existence of a black hole electron remains strictly hypothetical

Thank you transition. That’s more than I wanted to say. Yes, a “naked singularity” fits the bill.

An electron has the properties of mass, charge and spin, and is a point-like particle.
A black hole has the properties of mass, charge and spin, and is a point-like particle.
An electron has a classical radius, but obects can approach closer than the classical radius (hence like a naked singularity), its radius in quantum mechanics is exactly zero. Finite mass in zero radius makes a black hole, doesn’t it.

Just because the mathematical simplified model of an electron in one or more theories treats the electron as a point, it doesn’t mean an electron is a point.

dv said:

The Rev Dodgson said:

mollwollfumble said:

Nah,

From the very beginning, there have been people who don’t believe in black holes, it’s become something of a religious cult to deny the existence of singularities.

But electrons are singularities, so wake up.

Sigh

What makes you think electrons are singularities?

And black holes can exist without singularities.

I mean it makes GR a lot simpler if fundamental particles are taken to be pointlike…

Assuming singularities makes lots of things simpler, but in every case where we can actually check whether there is a singularity or not, there isn’t.

The Rev Dodgson said:

dv said:

The Rev Dodgson said:

Sigh

What makes you think electrons are singularities?

And black holes can exist without singularities.

I mean it makes GR a lot simpler if fundamental particles are taken to be pointlike…

Assuming singularities makes lots of things simpler, but in every case where we can actually check whether there is a singularity or not, there isn’t.

Yes …

Though in fairness it would be pretty hard to prove something was really a singularity even if it were one. All you could do is continually revise down the minimum scale at which the assumption fails.

There are some things we will never know.

But your key point is apt, black holes don’t require singularities.

dv said:

Though in fairness it would be pretty hard to prove something was really a singularity even if it were one. All you could do is continually revise down the minimum scale at which the assumption fails.

There are some things we will never know.

But your key point is apt, black holes don’t require singularities.

“ it would be pretty hard to prove something was really a singularity even if it were one” is indisputable.

The Rev Dodgson said:

dv said:

Though in fairness it would be pretty hard to prove something was really a singularity even if it were one. All you could do is continually revise down the minimum scale at which the assumption fails.

There are some things we will never know.

But your key point is apt, black holes don’t require singularities.

“ it would be pretty hard to prove something was really a singularity even if it were one” is indisputable.

I won’t dispute it.

Ian said:

The Rev Dodgson said:

dv said:

Though in fairness it would be pretty hard to prove something was really a singularity even if it were one. All you could do is continually revise down the minimum scale at which the assumption fails.

There are some things we will never know.

But your key point is apt, black holes don’t require singularities.

“ it would be pretty hard to prove something was really a singularity even if it were one” is indisputable.

I won’t dispute it.

Glad to here it :)

I probably should have put an “I agree that” on the front, to make it clear that I was just agreeing with what dv said.

Latest picture of the centre of the Milky Way, combining X-ray and radio.

Without annotation.

In X-ray left and radio right.