Something new under the sun

[Ziggurat]

I just find it hard to comprehend how more than one person can believe this nonsense.

So do I. But it's an observational fact that the world is full of lunatics, and the internet doesn't filter them out, it collects them.

We also had an argument about the many worlds interpretation of QM, if I recall. Actually you said something interesting there which I'm still thinking about (although of course you were still wrong ).

Well, as long as I was interesting, I don't mind being wrong.

 

[iantresman]

So which is it Zeuzzz? Is it gravity or is it your EM-plasma gnomes that are dominating the large scale structure of the universe?

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The largest coherent structure in the Solar System, is the heliospheric current sheet; electromagnetism dominates. A galactic analog would be somewhat bigger; electromagnetism dominates.

M87's plasma jet extends some 5000 light-years (Ref). It looks pretty structured and pretty large scale to me; electromagnetism dominates.

That's not to say that gravity is insignificant.

 

[Ziggurat]

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The largest coherent structure in the Solar System, is the heliospheric current sheet; electromagnetism dominates. A galactic analog would be somewhat bigger; electromagnetism dominates.

Largest by what measure? Size? Perhaps. Mass? Not a chance. In terms of mass, Jupiter dominates the solar system outside the sun itself. And its primary interaction is very much dominated by gravity. Likewise, the primary force on the sun, which itself makes up most of the mass of the solar system, is also gravity.

 

[Reality Check]

The largest coherent structure in the Solar System, is the heliospheric current sheet; electromagnetism dominates. A galactic analog would be somewhat bigger; electromagnetism dominates.

M87's plasma jet extends some 5000 light-years (Ref). It looks pretty structured and pretty large scale to me; electromagnetism dominates.

That's not to say that gravity is insignificant.

iantresman, The M87 plasma link is great! I especially like the explanation

An energetic jet from the core of giant elliptical galaxy M87 stretches outward for 5,000 light-years. This monstrous jet appears in the panels above to be a knotted and irregular structure, detected across the spectrum, from x-ray to optical to radio wavelengths. In all these bands, the observed emission is likely created as high energy electrons spiral along magnetic field lines, so called synchrotron radiation. But what powers this cosmic blowtorch? Ultimately, the jet is thought to be produced as matter near the center of M87 swirls toward a spinning, supermassive black hole. Strong electromagnetic forces are generated and eject material away from the black hole along the axis of rotation in a narrow jet. Galaxy M87 is about 50 million light-years away and reigns as the large central elliptical galaxy in the Virgo cluster.

(emphasis added)

You are right - electromagnetic forces dominate here. But these forces are not spread along the 5,000 light-years of the jet. They are situated at the supermassive black hole, probably concentrated within a few light-years or even less. The pictures are great proof that supermassive black holes exist.

 

[sol invictus]

M87's plasma jet extends some 5000 light-years (Ref). It looks pretty structured and pretty large scale to me; electromagnetism dominates.

Really?

So why can't photons or charged particles (or anything else) escape from that black hole?

 

[MattusMaximus]

We also had an argument about the many worlds interpretation of QM, if I recall. Actually you said something interesting there which I'm still thinking about (although of course you were still wrong ).

Cool, I'd love to be in on that discussion. The many-worlds interpretation of QM is something that I've been attempting to grapple with for some time, and I'd love to hear other (informed) thoughts on the matter.

Do I smell another thread?

 

[MattusMaximus]

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The largest coherent structure in the Solar System, is the heliospheric current sheet; electromagnetism dominates. A galactic analog would be somewhat bigger; electromagnetism dominates.

M87's plasma jet extends some 5000 light-years (Ref). It looks pretty structured and pretty large scale to me; electromagnetism dominates.

That's not to say that gravity is insignificant.

Ahem, when cosmologists say "large scale structure of the universe," they're generally talking in terms of billions of light years. 5000 light years is a wee bit smaller than that...

 

[iantresman]

The largest coherent structure in the Solar System, is the heliospheric current sheet; electromagnetism dominates

Largest by what measure? Size? Perhaps. Mass? Not a chance. In terms of mass, Jupiter dominates the solar system outside the sun itself. And its primary interaction is very much dominated by gravity. Likewise, the primary force on the sun, which itself makes up most of the mass of the solar system, is also gravity.

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Indeed, the heliospheric current sheet is clearly not have the largest structure by mass, and clearly the primary force on Jupiter and Sun are gravity. But the primary force on the Solar Wind is electromagnetic, overcoming Solar gravity with ease. The Sun flares, city power stations get knocked off line.

 

[iantresman]

iantresman, The M87 plasma link is great! I especially like the explanation

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I like the bit (emphasis added)

Strong electromagnetic forces are generated and eject material away from the black hole along the axis of rotation in a narrow jet. Galaxy M87 is about 50 million light-years away and reigns as the large central elliptical galaxy in the Virgo cluster.:

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You are right - electromagnetic forces dominate here. But these forces are not spread along the 5,000 light-years of the jet. They are situated at the supermassive black hole, probably concentrated within a few light-years or even less. The pictures are great proof that supermassive black holes exist.

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I disagree with you here. The jet is collimated due to magnetic fields, and has many characteristics of particle beams. Along the jet, it's electromagnetic forces all the way.

 

[Reality Check]

iantresman, We may have to agree to disagree about whether electromagnetic forces "dominate". There is a jet and the magnetic fields in it that cause the observed radiation could be collimating it. The papers that I can find offer are mixed, e.g.

from 'Doppler boosting, superluminal motion, and the kinematics of AGN jets' by Kellermann, K.I., et. al. published in Astrophysics and Space Science 311 (1-3), pp. 231-239 (2007)
"Sometimes, different features in a given jet appear to follow the same curved path but there is evidence for ballistic trajectories as well."

Gravity is the principal actor at the black hole since it is the cause of the jets. I agree that electromagnetic forces dominate in the jet beacuse it is a plasma and plasma are electromagnetic in nature. But plasmas are neutral overall and so gravity dominates outside the jet.

 

[Dancing David]

David why do you insist on demonstrating that you haven't even tried to understand what plasmoids are made of or what forces form them?

Why don't you demonstrate how a plasmoid can maintain against gravitational collapse?

You aren't doing that, now are you ? But I am sure your political shilling for the powers that be pays the bills, so such appeals to emotion and evasions put food on your table.

They do not however answer the question:

What will keep the plasmoid from undergoing gravitational collapse?
What force will keep it from contracting under the 'force of gravity'?

 

[Zeuzzz]

They do not however answer the question:

What will keep the plasmoid from undergoing gravitational collapse?

I presume that we are referring to a filamentary plasmoid? and why they do not collapse?

Plasmas display filamentary structures everywhere, from microscopic to galactic size. This structure derives from the fact that plasma, because of its free electrons, is a good conductor of electricity, far exceeding the conducting properties of metals such as copper or gold. Wherever charged particles flow in a neutralizing medium, such as free electrons in a background of ions, the charged particle flow or current produces a ring of magnetic field around the current, pinching the current into filamentary strands of conducting currents.

What force will keep it from contracting under the 'force of gravity'?

I would think the charge on the plasmoid could play a role in determining the maximum compression it can sustain, although this alone would certainly not stop the initiation of the collapse, it would put a limit on the ultimate size. If the gravitational force is compressing the plasma to a certain size, as this happens the repulsive force of the similar charges inside the plasma will increase with time, until the compressive force of gravity equals the repulsive force of the ions, leading to a state of equilibrium. The charge on the resulting object will be the same as the net charge previously on the diffuse cloud, but in a much denser state, with the like ions packed closely together. And voila! a gravity ionized star.


Speculations aside, I think that the main forces stopping gravitational collapse in large filamentary structures are the forces that arrise from plasma, and the E and B fields produced by the flow of particles. There are also many secondary effects that arrise from the EM fields, pinch effects (Bennett Pinch, Z-pinch, the force-free configuration, diocotron instability, CIV, etc) magnetic effects (Motion Induced Εlectric Fields, Faraday Disk Dynamo, Biot-Savart force, Faraday's Law, Unipolar inductors, etc) electrical effects (Birkeland currents, Thermoelectric Effect, Double layers, Magnetic Mirror Effect, Electrostatics, Particle Acceleration, etc) All these effects arrise from the EM fields when in certain conditions, and can have a considerable effect. I would say that the most important forces result from Double layers and Z-pinch effects, and also crucially important is the Biot-Savart force (sometimes just called Savart force), which can be worked out as a function of the spacing between helical current filaments, and usually produces rotational motion. I'm no Plasma Cosmologist, theres probably other forces and plasma based effects i have left out.

 

[Reality Check]

Zeuzzz, BeAChooser thinks the object detected at the center of the Milky Way is a "galactic sized plasmoid" (be aware that he waffles along about all sorts of plasma cosmology/electric universe pseudo-science).

Can plasmoids with a width of less than 100 AU have masses of the order of million(s) of solar masses?

The black hole at the center of the Milky Way has a lower limit of 400,000 solar masses and is likely to be 3.7 million solar masses (packed into a width of less than 45 AU). The M87 black hole has a mass of 3 billion solar masses.
In my original post I used the older mass for the Sagittarius A* black hole and misstated the maximum width as 1 AU.

 

[technoextreme]

EM forces are known to exist in space. They are unbelieveably stronger than gravity. Pick up a metal object with a magnet, and you have just demonstrated that a small EM attraction is able to overcome the gravitational attraction caused by the entire mass of the earth.

What about black holes though? There is nothing that can escape a black hole including electromagnetic fields (IE light).
EDIT: Bloody dam hell someone all ready asked that question.

 

[Zeuzzz]

Zeuzzz, BeAChooser thinks the object detected at the center of the Milky Way is a "galactic sized plasmoid" (be aware that he waffles along about all sorts of plasma cosmology/electric universe pseudo-science).

Can plasmoids have masses of the order of million(s) of solar masses?

What do you think a black hole is made of then?

 

[BeAChooser]

Can plasmoids with a width of less than 100 AU have masses of the order of million(s) of solar masses?

Can a plasmoid with a width less than 1 AU have a mass of 40,000 suns? Apparently, given the uncertainties, the data might be consistent with that.

The black hole at the center of the Milky Way has a lower limit of 400,000 solar masses and is likely to be 3.7 million solar masses (packed into a width of less than 45 AU).

http://www.nrao.edu/pr/2004/sagastar/ "The precision of these observations allows the scientists to say that a mass of at least 40,000 Suns has to reside in a space corresponding to the size of the Earth's orbit."

By the way, the theoretically predicted size of a black of 2.6 million sun mass is apparently 7.7 million km ... a small fraction of an AU, not tens of AU.

 

[Reality Check]

Can a plasmoid with a width less than 1 AU have a mass of 40,000 suns? Apparently, given the uncertainties, the data might be consistent with that.

BeAChooser - you may want to choose to read my later post:

The black hole at the center of the Milky Way has a lower limit of 400,000 solar masses and is likely to be 3.7 million solar masses (packed into a width of less than 45 AU). The M87 black hole has a mass of 3 billion solar masses.

Any kind of mass (solid, liquid, gas or plasma) weighing 400,000 solar masses packed into a 45 AU wide sphere is a black hole. This includes your hypothetical plasmoid.

By the way, the theoretically predicted size of a black of 2.6 million sun mass is apparently 7.7 million km ... a small fraction of an AU, not tens of AU.

Yes the PR report does state the calculated size of a black hole that is "nearly four million times more massive than the Sun". There is an entry on Wikipedia abut this black hole (Sagittarius A*) but I know you hate Wikipedia so here is the citation the entry used to the UCLA Galactic Center Group.

 

[Zeuzzz]

Einstein never belived in black holes, and wrote two papers in which he argued against their existence. And now people have gone off using his theory to 'prove' that black holes must exist, even though the very person who invented GR did not believe they could exist.

"Since the mathematicians have invaded the theory of relativity, I do not understand it myself anymore." Quoted in P A Schilpp, Albert Einstein

For example, when a star collpases under its own gravity to a single point, the very concept of a point is a mathematical abstraction. In other words, a point is a purely mathematical object. No-one has ever observed a point, and no-one will, because nature does not make points.

All the arguments for the black hole are theoretical, based solely upon the erroneous Hilbert solution and the meaningless Kruskal-Szekeres extension on it. One is therefore lead to wonder what it is that astronomers actually “see” when they claim that they have found yet another black hole here or there. Besides the purely mathematical errors that mitigate the black hole, there are also considerable physical arguments against it, in addition to the fact that no event horizon has ever been detected.

What does a material point mean? What meaning can there possibly be in the notion of a material object without any spatial extension? The term material point (or pointmass) is an oxymoron. Yet the black hole singularity is supposed to have mass and no extension. Moreover, there is not a single shred of experimental evidence to even remotely suggest that Nature makes material points. Even the electron has spatial extent, according to experiment, and to quantum theory. A “point” is an abstraction, not a physical object. In other words, a point is a purely mathematical object. Points and physical objects are mutually exclusive by definition. No one has ever observed a point, and no one ever will because it is unobservable, not being physical. Therefore, Nature does not make material points. Consequently, the theoretical singularity of the black hole cannot be a point-mass.

The problem with some aspects of black holes as they are currently described comes from mathematicians treating mathematical objects as real physical things, and propose these things as fact before any sort of observational evidence for their existance is collected.

 

[sol invictus]

Einstein never belived in black holes, and wrote two papers in which he argued against their existence.

He also made an extremely important contribution to quantum mechanics (for which he won the Nobel, not relativity) and yet in his later years couldn't accept the theory it gave birth to. Strangely, even though he wouldn't have believed in it, my computer seems to be working just fine.

How strange! Could it possibly be that Einstein was.... wrong??

And now people have gone off using his theory to 'prove' that black holes must exist, even though the very person who invented GR did not believe they could exist.

You have a very strange view of physics. To you, apparently, it matters to the validity of a theory what people think and thought about it. To the rest of us, there's a real world, and there are some theories, and some theories are good at describing the world and some are bad. It doesn't make the slightest difference what anyone thinks.

Anyway, you've finally answered the question - you don't believe in general relativity, then.

No-one has ever observed a point, and no-one will, because nature does not make points.

And just how the **** do you know that?

The problem with some aspects of black holes as they are currently described comes from mathematicians treating mathematical objects as real physical things, and propose these things as fact before any sort of observational evidence for their existance is collected.

The problem here is that (again) you don't have the slightest clue what you're talking about. GR is a mathematical theory. I know you don't understand math very well, but those of us that do can use it do find out what GR predicts.

 

[Zeuzzz]

No-one has ever observed a point, and no-one will, because nature does not make points.

And just how the **** do you know that?

Because I know the difference between a mathematical construct and something that actually exists. The same conceptual issue you had understanding that field lines do not actually exist, they are mathematical tools to represent the process occuring, not the actual process itself. The same for points, or singularities, they have never been observed and are useful mathematical tools only.

A point has no volume, area or length, making it a zero dimensional object.

I mainly just dont like the idea of black holes, something that you can't see or detect, how can you disprove something you cant directly detect?

What is a 'point' made of then? how do you test for it?