Dark matter hiding in stars may cause observable oscillations

September 18, 2015 by Lisa Zyga feature
This sequence shows snapshots of a star’s density when two dark matter cores collide, where the x-axis is the plane of collision (only half the space is shown, but the remaining space can be obtained by symmetry). Although the final configuration is more compact and massive than the original, the star does not collapse into a black hole because it ejects some of its mass, slowing down its growth so that it remains stable. Credit: Brito, et al. ©2015 American Physical Society

(Phys.org)—Dark matter has never been seen directly, but scientists know that something massive is out there due to its gravitational effects on visible matter. One explanation for how such a large amount of mass appears to be right in front of our eyes yet completely invisible by conventional means is that the dark matter is hiding in the centers of stars.

In a new study, physicists have investigated the possibility that large amounts of hidden mass inside might be composed of extremely lightweight hypothetical particles called axions, which are a primary dark matter candidate. The scientists, Richard Brito at the University of Lisbon in Portugal; Vitor Cardoso at the University of Lisbon and the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, Canada; and Hirotada Okawa at Kyoto University and Waseda University, both in Japan, have published their paper on dark matter in stars in a recent issue of Physical Review Letters.

"Our work studies how dark matter piles up inside stars if the dark matter is composed of massive bosonic particles (axions are an example of such particles)," Brito told Phys.org. "Our results show that dark matter accretion by stars does not lead to gravitational collapse; instead it may give rise to characteristic vibrations in stars."

The researchers theoretically showed that, if numerous axions were to pile up inside normal stars, then the dark matter core would oscillate. The oscillating core would in turn cause the star's fluid to oscillate in tune with it at a specific frequency related to the star's mass, or at multiples of this frequency. For a typical axion mass, the oscillating stars would emit microwave radiation and might have observable effects.

"What oscillates is the fluid density and its pressure, but it's probably correct as well to say that the entire star is oscillating," Brito explained. "These are like sound waves propagating through the fluid, with a very specific frequency. Oscillations of this kind could, for example, lead to variations in the luminosity or in the temperature of the star, and these are quantities that we can measure directly.

"In fact, there is already a whole branch of physics called asteroseismology, which studies the internal structure of stars by observing their oscillation modes. This is very much like the way scientists study the internal structure of the Earth by looking at seismic waves. It is possible that the oscillations of a star driven by a dark matter core could also be observed using similar methods. Given the very specific frequencies at which these stars would vibrate, this could be a smoking gun for the presence of dark matter. Asteroseismology is still in its infancy but it will, almost certainly, become a very precise way of observing stars in the future."

In previous research on dark matter stars, it has often been assumed that stars accreting dark matter will continue to grow until they become so dense that they collapse into black holes. However, in the new study the physicists' simulations showed that these stars actually appear to be stable and do not become black holes. Their stability arises from a self-regulatory mechanism called "gravitational cooling" in which the stars eject mass to slow down and stop their growth before they approach the critical Chandrasekhar limit, the point at which they collapse into black holes.

As the scientists explain, the finding that dark matter stars are stable makes a surprising contribution to the research in this area.

"Although it was known for some time that dark matter can be accreted by stars and form dark matter cores at their center, those studies were all phenomenological," Brito said. "In addition, basically all these studies suggested that, if enough dark matter is accreted by a star, it will eventually trigger and a black hole would form, eventually eating all the star.

"We set about checking these claims, using a rigorous fully relativistic framework, i.e., solving the full Einstein's equations. This is important if we want to understand how the dark matter core behaves for large densities. Well, it turns out that our results show that black hole formation can, in principle, be avoided by ejecting excessive mass: the dark matter core starts 'repelling' itself when it is too massive and compact, and is unable to grow past a certain threshold. This is, as far as we know, something that was ignored in previous works.

"The above results are quite generic. Because any self-gravitating massive bosonic field can form compact structures, any such putative dark matter component would lead to the kind of effects we discuss in our paper. In this sense it proposes another way to search for these kinds of particles that can be complementary to observations coming from cosmology, for example. Given the lack of information that we have about the nature of dark matter, we think that it might be worth the effort to further develop this subject."

The scientists hope that the results here may help guide future research by suggesting where to look for dark matter and what methods to use to detect it.

"We don't know much about dark matter," Brito said. "The only thing we do know is that all kinds of matter (be it regular matter or dark, invisible matter) fall in the same way in gravitational fields. This is Einstein's equivalence principle in action. Thus, dark matter also falls in the usual way. It seems therefore appropriate to look for effects of dark matter in regions where gravity is strong, like neutron stars, , etc. We are now trying to understand how dark matter behaves generically in regions of strong gravity.

"At this precise moment, we are working on a long version of this letter. We want to understand in depth how the core grows for different kind of scenarios, and how viscosity in the star's material affects the development of the accretion process."

Explore further: Dark matter guides growth of supermassive black holes

More information: Richard Brito, Vitor Cardoso, and Hirotada Okawa. "Accretion of dark matter by stars." Physical Review Letters. DOI: 10.1103/PhysRevLett.115.111301, Also at arXiv:1508.04773 [gr-qc]

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abecedarian
5 / 5 (5) Sep 18, 2015
If dark matter were such a substantial component of stars, wouldn't the affect on observable stellar mass cause gravitational effects on surrounding bodies that differ from what's observed?
Mike_Massen
2.5 / 5 (8) Sep 18, 2015
abecedarian asked
If dark matter were such a substantial component of stars, wouldn't the affect on observable stellar mass cause gravitational effects on surrounding bodies that differ from what's observed?
That would depend upon its relative gravitational distribution function

ie. Although there's evidence at personal local scales of imperative gravitational forces offer, their predictability & utility eg. re satellites, probes, planetary motions then given what we observe re the so called galactice "rotation curves" there need not be expectation so called dark matter(DM) has to conform to such coalescence behavior as to be substantive

Eg. It might be that DM has some inherent repulsion property but only at local scales which isnt evident at all on larger scales so it is almost always dispersed. This could have a wavelike aspect such as peaks & troughs but, on astronomical scale.

Fact gravitation works so well at our solar scale suggests issue isn't simple
jalmy
2.8 / 5 (16) Sep 18, 2015
Sorry DM believers. Time for monkey to grasp at another straw. Stick a monkey in a room with thousands of cards with random answers and ask it questions. This is DM science.
Doug_Huffman
5 / 5 (5) Sep 18, 2015
Substantial stellar DM should confound the well understood nuclear physics, even falsify it.
plasmasrevenge
2.1 / 5 (13) Sep 18, 2015
What we see is that gravity is insufficient to cause the observed motions. The speculation that there is some added matter which is causing those anomalous motions is an added step of logic. The reporting on this subject combines this observation and speculation into one single logical unit, in order to save the scientific framework.

The public need not adopt the scientific community's bias towards saving the scientific framework, and in fact should realize that this bias can undermine the scientific community's ability to solve these exact problems.

This current dark matter speculation seeks to add yet another speculation on top of those which already exist. Yet, proposing that DM can exist in stars does nothing at all to resolve the existing anomalous observations, so why bother?

The public should take a very strong stance against the addition of more speculations which fail to solve the original problem.
Hyperfuzzy
2 / 5 (4) Sep 18, 2015
maybe the protons and electrons have no mass, only charge. maybe the idea of mass is only an approximation of the superimposed field from the particles; hence, G is not a constant. juz say'n

maybe we are wrong! maybe there is no invisible "dark" stuff, maybe there are no ghosts. maybe, maybe is not the best theory, maybe we are a planet of fools
Scroofinator
1.8 / 5 (5) Sep 18, 2015
maybe the protons and electrons have no mass, only charge. maybe the idea of mass is only an approximation of the superimposed field from the particles


That's my take too. There is no mass, only energy.
druc iulian
2.3 / 5 (6) Sep 18, 2015
Another simulation. Maybe some facts some times?
plasmasrevenge
2 / 5 (8) Sep 18, 2015
Re: "Fact gravitation works so well at our solar scale suggests issue isn't simple"

What this suggests is that gravity might only dominate at our small scale, and only when there are no transient electrical events to supersede it. When Einstein proposed Relativity, space was widely assumed to be an empty vacuum. When we sent the first rockets up, some 40 years later (!), we encountered copious amounts of high-energy charged particles. Einstein was not even alive for that discovery, which occurred in 1959. He died in 55.

Theorists have never actually altered the textbooks in any significant way to reflect that discovery.

If gravity was just a localized force, dominant at only particular scales, it would not be an extraordinary claim. That's pretty much what the Van der Waals force is, as well.
Zzzzzzzz
3.1 / 5 (15) Sep 18, 2015
Exploration of possibilities, no matter how foolish sounding to some, is required to reach the point of understanding. Ridicule has its place I suppose, but it is very quickly overdone.
plasmasrevenge
2 / 5 (8) Sep 18, 2015
It also pays attention to watch what is coming. Herschel's observation of "ubiquitous filamentation" (ESA's term) at all scales of astronomical observation has been very widely ignored, even though it is very clear at this point that whatever is inducing that filamentation is also a fundamental mechanism for the formation of stars.

This dismissal will come to haunt advocates of the textbook theories. They are pretending like they can continue on, business-as-usual, without engaging the implications of that observation.

But, this story has only just begun, for the James Webb telescope is tuned to observe the very same phenomenon. The problems for the conventional textbook theories has honestly just begun. A person could look at the Hubble images and safely ignore the filaments, but that won't be the case with these newer images.
Scroofinator
1 / 5 (1) Sep 18, 2015
What this suggests is that gravity might only dominate at our small scale

Rather, it only dominates within it's range of complete influence i.e the heliosphere for our sun. We have only conducted experiments within our "box" so it wouldn't be surprising if GR needs updating outside these limits.

Brings to mind the gas cloud G2's close encounter with SagA*. It was expected to be consumed (at least partially) by the SMBH, but orbited around it with only slight deformation.
http://phys.org/n...ter.html
The guess as to why GR was unable to accurately predict the cloud's movement is because there some "hidden" large mass at the center of the cloud.

My argument is that since this did not occur in a 'solar sphere' but rather a 'black hole sphere' the physics are slightly different, hence the cloud's unexpected transit.
Protoplasmix
3.9 / 5 (7) Sep 18, 2015
What we see is that gravity is insufficient to cause the observed motions. The speculation that there is some added matter which is causing those anomalous motions is an added step of logic. The reporting on this subject combines this observation and speculation into one single logical unit, in order to save the scientific framework.
—plasmasrevenge

Dude, you've neglected to mention the many gravitational lensing observations. Kindly return to your drawing board, or whatever it is you use for your calculations.
The public should take a very strong stance against the addition of more speculations which fail to solve the original problem.
We'll take a strong stance against any pseudoscience, thanks.
baudrunner
1.8 / 5 (5) Sep 18, 2015
"Fluid" behavior in stars? That's just like saying the sun is a giant gas ball, which is silly. Never mind that gravity is so strong in a star that those oscillations that they are looking for will have originated about ten million years ago. DM is just bad theory, based on bad math. Scientists think they know too much.
flag
1 / 5 (1) Sep 18, 2015
https://www.acade...etectors
The gravitational force attracting the matter, causing concentration of the matter in a small space and leaving much space with low matter concentration: dark matter and energy. There is an asymmetry between the mass of the electric charges, for example proton and electron, can understood by the asymmetrical Planck Distribution Law. This temperature dependent energy distribution is asymmetric around the maximum intensity, where the annihilation of matter and antimatter is a high probability event.
carlo_piantini
1.5 / 5 (11) Sep 18, 2015
Sometimes, I'd really love to do an AMA with astrophysicists, and glean more about their reasoning. Honestly - I'm a student, and while I'm very, very strongly interesting in test alternative electromagnetic hypothesis about, say, the structure of the solar system, I'm also interested in learning the textbook theory. It seems particularly bizarre to me that the plasma within the Sun, at least from this description, seems to be behaving as an electrostatic oscillator, and yet astrophysicist are trying to describe the behavior of the plasma in terms of a gravitational component which is not only completely hypothetical and unobservable, but not even supported by experimentation. The CAST experiment has spent the last twelve years failing to detect any kind of axions from the Sun: http://home.web.c...or=mauve
carlo_piantini
1 / 5 (8) Sep 18, 2015
@plasmasrevenge: Honestly, there are serious historical scientific choices which need to be re-evaluated, despite the idea that they may come at the cost of the present paradigm. The presence of the entire heliosphere, and it's implications, still really haven't been considered. Before Newton's idea of gravitation rose to dominance, the best idea of the mechanism that drove the solar system was Descartes' theory of vortices, i.e., the Sun sat at the center of an enormous vortex of "imperceptible matter", within which sit the planets, and which drives their rotations and revolutions. As it turns out, that theory was argued against by Newton, who proposed gravitation as an answer. In fact, in France, for a long time Descartes' view was still held in favor even after Newton published his heuristic for gravitation.
carlo_piantini
1 / 5 (7) Sep 18, 2015
Still, Newton's theory is predicated on the physical axioms that space exists as a vacuum; there is no matter occupying the space, and there is certainly nothing flowing through it. As a matter of fact, this idea was one of theoretical barriers that impeded our correct understanding of the aurora, which belonged to Birkeland. Still, we know now that not only was Newton's theory of the solar vacuum incorrect, but in fact, we also know that Descartes' theory of the solar vortex is correct - it exists as the Parker Spiral of the heliosphere, and it stretches well past Pluto. I think it would be incredible if electrical engineers/plasma physicists took up Birkeland's example, approximated the heliospheric current sheet in a terrella/sollellus experiment, and attempted to see whether the terrella's revolve/rotate.
mytwocts
4.3 / 5 (12) Sep 18, 2015
"Fluid" behavior in stars? That's just like saying the sun is a giant gas ball, which is silly. Never mind that gravity is so strong in a star that those oscillations that they are looking for will have originated about ten million years ago. DM is just bad theory, based on bad math. Scientists think they know too much.

They know more than you, so much is clear from your post.
The article is here: http://arxiv.org/...08.04773
carlo_piantini
1 / 5 (8) Sep 18, 2015
Man, I've gotta seriously laugh at the rating bias on this site sometimes. Recount the historical development of Descartes theory, and Newton's opposition to it in favor of gravitation? 1-Star for you. Point out that Descrates' physical premise was undeniably right, and Newton's was undeniably wrong? 1-Star. Mention that a scientific experiment has spent over a decade making failed attempts to detect axions from the Sun, with a provided link? 1-Star.

But yeah, there's no bias happening on this site at all...
dogbert
3.9 / 5 (7) Sep 18, 2015
The longer dark matter remains undiscovered, the more frantically everyone keeps looking for it. I suppose there is still a lot of grant money to anyone who works on dark matter.

Everything works just fine in our solar system without any dark matter requirements, yet everywhere else in the universe, dark matter is supposed to dominate mass. What more is necessary to show that dark matter simply does not make sense?
Scroofinator
1 / 5 (1) Sep 18, 2015
in fact, we also know that Descartes' theory of the solar vortex is correct - it exists as the Parker Spiral of the heliosphere


It makes sense, we are just following in the wake of Sol. It's like water right behind a speeding boat compared to that of the surface around it, the waves directly behind the boat are traveling with much more force. Waves are just a 2D representation of the funnel like flow of time/energy in 3D. The thing with three dimensions is that the planets don't ride the wave, it just speeds them up or slows them down.

Which takes me back to my point: why should the laws of physics be the same inside as they are to out? There's less energy away from large bodies so by definition there's less mass.

there's no bias happening on this site at all

Ya there's a bunch of closed minded people riding around in a 100 year old car, who cares. Einstein himself was still searching for the answer, so why we think we know it all confuses the shit out of me...
Mimath224
3 / 5 (1) Sep 18, 2015
I'm not 'up' on Axions but if they were produced by the BB wouldn't strong mag fields in/on our own Sun produce some notable effect? I read that there is an axion-photon conversion relationship (x or gamma?) so is there is a particular photon frequency that might be a signature? I'm a little confused about other articles that also suggest that axions weakly interact with electrons so I don't quite understand how they are produced in a star's core. Perhaps someone here might help...genuine questions. Thanks
qitana
1 / 5 (1) Sep 18, 2015
Dark matter is matter that is conceiled by aliens. It's normal matter but the aliens are so advanced that they have the technology to conceil it from outsiders. That's why there is none in our solar system. They don't want to make it too obvious.

I'm just joking.
viko_mx
1.1 / 5 (10) Sep 19, 2015
Modern cosmology - the fertile environment for all speculators. This steady trend is making mockery with science. Where are the old hones fruitful scientists? Where are we going? To new dark age?
jljenkins
3.2 / 5 (15) Sep 19, 2015
Man, I've gotta seriously laugh at the rating bias on this site sometimes. Recount the historical development of Descartes theory, and Newton's opposition to it in favor of gravitation? 1-Star for you. Point out that Descrates' physical premise was undeniably right, and Newton's was undeniably wrong? 1-Star. Mention that a scientific experiment has spent over a decade making failed attempts to detect axions from the Sun, with a provided link? 1-Star.

But yeah, there's no bias happening on this site at all...


The one star votes are just our friendly way of telling you to go to hell. You're an irritating git.
jim_xanara
2.8 / 5 (9) Sep 19, 2015
Dark matter is matter that is conceiled by aliens. It's normal matter but the aliens are so advanced that they have the technology to conceil it from outsiders. That's why there is none in our solar system. They don't want to make it too obvious.

I'm just joking.

Good you added that. The statement doesn't sound 1/2 as absurd as what CP says in seriousness. You're way ahead of benni/returners, zephir/docile, antigoracle, cantdrive85, JVK, viko_mx and ryggesogn, as far as making any coherent sense goes!!!
jim_xanara
2.5 / 5 (11) Sep 19, 2015
Don't forget bschott and ren82. They're stupid even for that lot.
mytwocts
4.3 / 5 (6) Sep 19, 2015

But yeah, there's no bias happening on this site at all...

People just don't agree with you. That is not the same as bias.
mytwocts
4.1 / 5 (10) Sep 19, 2015
The longer dark matter remains undiscovered, the more frantically everyone keeps looking for it.

If DM had already been discovered there would be no need to look for it. Can you follow?
I suppose there is still a lot of grant money to anyone who works on dark matter.

Yeah, work on DM and get rich. Obviously you have never been a postdoc.
docile
Sep 19, 2015
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docile
Sep 19, 2015
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docile
Sep 19, 2015
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docile
Sep 19, 2015
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docile
Sep 19, 2015
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viko_mx
1 / 5 (4) Sep 19, 2015
@mytwocts

There is no place in true scientific cites for anomimous professional emotional voters that have no conection with reality and science respectively. It seems that people like you are relying on the consensus but from human history we no that the truth can not obtained by consensus. The consesus only show the beleave system of the majority in one society. But they usualy are wrong.
docile
Sep 19, 2015
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mytwocts
4.5 / 5 (8) Sep 19, 2015
@mytwocts

There is no place in true scientific cites for anomimous professional emotional voters that have no conection with reality and science respectively.

Exactly my point, which you are copying (again).
So what are you doing here?
docile
Sep 19, 2015
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mytwocts
4.2 / 5 (5) Sep 19, 2015
But why the common particles cannot evaporate in the same way

"evaporate" here means emit elementary particles. A proton or an electron cannot do that.
their diameter is very small and for such a case the theory predicts massive evaporation.

Only if one considers a proton or an electron to be a black hole, which is not at all an accepted POV.

As the result, common particles will evaporate well before they can reach the black hole - but not because of dark matter, but due to Hawking mechanism taken into account consequentially.

Not a valid conclusion because the assumption is incorrect.
Alternatively we may think, that these particles will get ripped with strong gravity field due to spaghettization - again, no dark matter is needed for explanation, why the black hole cannot grow anymore.

Ripped into what ? Protons and electrons are elementary particles.
docile
Sep 19, 2015
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docile
Sep 19, 2015
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mytwocts
4.5 / 5 (8) Sep 19, 2015
Actually all temporal effects and phenomena also violate the 4D space-time concept - because in this space-time is otherwise static.

Self-contradictory nonsense.
What are you smoking ?
docile
Sep 19, 2015
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docile
Sep 19, 2015
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docile
Sep 19, 2015
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docile
Sep 19, 2015
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Benni
2.5 / 5 (8) Sep 19, 2015
Dark matter is matter that is conceiled by aliens. It's normal matter but the aliens are so advanced that they have the technology to conceil it from outsiders. That's why there is none in our solar system. They don't want to make it too obvious.

The statement doesn't sound 1/2 as absurd as what CP says in seriousness. You're way ahead of benni/returners, zephir/docile, antigoracle, cantdrive85, JVK, viko_mx and ryggesogn, as far as making any coherent sense goes!!!


Obviously it is unbeknownst to you that Einstein in GR derived the exact calculations for gravitational lensing based solely on the visible mass of the Sun as starlight passes its peripheral disk. Einstein was smart enough to do this 20 years prior to Zwicky proposing DM.

It isn't unscientific reasoning to challenge the existence of something when hypotheses for the existence of DM is so obviously contrived that the DM Enthusiasts continually need to reconstruct their theories for locating it.
docile
Sep 19, 2015
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mytwocts
4.6 / 5 (9) Sep 19, 2015
Tell us more about your close friend Einstein and GR. Does GR involve DE?
No one knows so much about this subject as you!
Fortunately you post regular updates on phys.org.
Einstein foresaw DM theory already in 1916 and decided not to go along.
Just like you, Benni.
Benni
2.5 / 5 (8) Sep 19, 2015
The fact that Einstein derived the calculations for gravitational lensing 20 years prior to Zwickey proposing an envelope of DM creating extra-galactic forces of gravity keeping Spiral galaxies from flying apart should be a clue that Zwickey was on the wrong track right at the start.

Zwickey's concept of for DM sourced gravity inspired present day contrivances that 75-90% of the Universe is missing even though all the gravity within our solar system is solely accounted by its Visible Mass. DM Enthusiasts populating this site won't stand for such scientific reasoning, so they start right in with their name calling & profanity routines for which they are challenged to scientifically prove the existence of & are unable to do it because they fail miserably in their comprehension of Einstein's GR, if in fact any of them have even bothered to study anything in it.

Hey jim_x, I have studied GR & never come across the name calling routines & profanity you use on others..

docile
Sep 19, 2015
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Benni
1.9 / 5 (9) Sep 19, 2015
Tell us more about your close friend Einstein and GR. Does GR involve DE?
No one knows so much about this subject as you!
Fortunately you post regular updates on phys.org.
Einstein foresaw DM theory already in 1916 and decided not to go along.
Just like you, Benni.


.......then I can only conclude that Einstein was not only a lot smarter than Zwickey, but also yourself.
docile
Sep 19, 2015
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docile
Sep 19, 2015
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carlo_piantini
1 / 5 (3) Sep 19, 2015
@jljenkins: Well, at least you're trying to be friendly. Gotta respect that I suppose...

@mytwocnts: It's not something you can have an opinion over, it stands of a fact of empirical observation - Newton was wrong about space being a vacuum, and Descartes was correct about the existence of the Parker Spiral. Just as well, he also managed to predict the existence of the magnetosphere, some ~300 years before either were detected by satellites: http://plato.stan...physics/
carlo_piantini
1 / 5 (4) Sep 19, 2015
Unless anyone one here wants to sit and argue about what is universally recognized as fact, i.e., that space is not a vacuum, then I'm not sure what the debate is about here. Newton's entire physical picture of the solar system was wrong: (a) he asserts that that space within the solar system between bodies is a vacuum - it absolute is not (b) he asserts that electricity and magnetism have no place in deriving celestial mechanics, and that gravitation is the only force at play - again, he was wrong. He describes all of this in "The Principia".

Meanwhile, the magnetosphere of the Earth exists, the Parker Spiral/heliospheric current sheet exists, and the Sun as a massive body of "primary matter" i.e. plasma at the center, driving the rotation of the sheet, also exists. Descartes predicted all of them in "The World" and "Principles of Philosophy". None of that is opinion, it's history and it's empirical fact.
carlo_piantini
1 / 5 (3) Sep 19, 2015
My suggestion to study the implications of that experimentally is just that - a suggestion, driven by natural curiosity at the fact that regardless of how well Newton's mathematics work, his physical picture of space is completely wrong, and Descartes was startlingly correct, which anyone can learn by picking up his freaking books and reading for themselves. Unless Descartes has *also* become a crank, in your opinion...
docile
Sep 19, 2015
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carlo_piantini
1 / 5 (4) Sep 19, 2015
I proposed a scientific experiment - build a vacuum chamber big enough to house multiple terrellas. Allow the terrellas to rotate on their axis, and to revolve around a central sollellus that acts either as anode or cathode. Birkeland had success with cathode, Childs has had very successful results with an anode. Fill the chamber with hydrogen. Begin to rotate the sollellus so that the magnetic field, which extends to the barrier of the chamber, also rotates, and begins to drag the hydrogen in the chamber with it, the exact same way the Parker Spiral is generated by the Sun's magnetic field in the heliospheric current sheet. And then, see if any kind of rotation or revolution happens with the terrellas. Do they rotate? Do they revolve? I have no idea, but I think it would be extremely interesting to find out. It worked wonders for Birkeland.
docile
Sep 19, 2015
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docile
Sep 19, 2015
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cracker_mon
1.8 / 5 (5) Sep 19, 2015
There is no dark matter. What is perceived as dark matter is simply gravitational energy, which actually needs no mass to exist. Gravitational energy focuses through planets,stars, etc: and gives the impression of emanating from those sources but in reality is a force that is simply there. It surrounds everything. That is the simple explanation without all the big words.
swordsman
3 / 5 (2) Sep 19, 2015
Judging from the above comments, everything is clear about Dark Matter now.
docile
Sep 19, 2015
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docile
Sep 19, 2015
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docile
Sep 19, 2015
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zz5555
3 / 5 (4) Sep 19, 2015
There is no dark matter. What is perceived as dark matter is simply gravitational energy, which actually needs no mass to exist. Gravitational energy focuses through planets,stars, etc: and gives the impression of emanating from those sources but in reality is a force that is simply there. It surrounds everything. That is the simple explanation without all the big words.

I don't claim to know much about dark matter, so imagine my surprise when I clicked on this article and found that the dark matter (and gravity) is just the Force! Go Jedi!
DanV
1 / 5 (4) Sep 19, 2015
Wrong. There is said dark matter is always falling, but dark matter isn't always falling!!! It has the power to expand space !! Look at the spave around gallaxies: There dark matter expands space to stabilize the galaxy's gravitational behaviour when the dark matter-massdensity becomes 1/4 of the Newton-massdensity for visible light. Seperate research is held about this phenomenon.
sandler
1 / 5 (1) Sep 20, 2015
Does hiding dark matter follows 80-20 rule (for density) inside these stars..? Where as normal matter (mostly hydrogen) follows 20-80 rule thus taking up more space for less mass..
https://en.wikipe...rinciple
mytwocts
5 / 5 (5) Sep 20, 2015
Unless anyone one here wants to sit and argue about what is universally recognized as fact, i.e., that space is not a vacuum,

So Newton was wrong and space is not a vacuum. You repeatedly claimed to be a student. I do not believe that to be a fact. Any university teaching such material should immediately lose its funding and status.
mytwocts
4.4 / 5 (7) Sep 20, 2015
@Docile
Everything you write is nonsense.
The sheer volume of it is your only weapon.
mytwocts
3.4 / 5 (5) Sep 20, 2015
@CP
" magnetic field ... also rotates"
Magnetic fields do not rotate.
mytwocts
4.3 / 5 (6) Sep 20, 2015
Tell us more about your close friend Einstein and GR. Does GR involve DE?
No one knows so much about this subject as you!
Fortunately you post regular updates on phys.org.
Einstein foresaw DM theory already in 1916 and decided not to go along.
Just like you, Benni.


.......then I can only conclude that Einstein was not only a lot smarter than Zwickey, but also yourself.

First learn to spell the names of the great scientist you compare yourself with.
You sloppy narcissist!
In order to know who is the smartest between Einstein, Zwicky and me, you would have to be as smart as you think you are, but you are not.
docile
Sep 20, 2015
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Noumenon
3.7 / 5 (3) Sep 20, 2015
the stars eject mass to slow down and stop their growth before they approach the critical Chandrasekhar limit, the point at which they collapse into black holes.


This is what I do to.
Noumenon
3.7 / 5 (3) Sep 20, 2015
@CP
" magnetic field ... also rotates"
Magnetic fields do not rotate.


The magnetic field vector component of circular polarized electromagnetism does.

I'm being a smart-ass to show it depends on the circumstances. I'm not agreeing with cp, but pointing out that you have spliced and parsed his words in such a manner that it appears to exclude those conditions.
TopCat22
1 / 5 (3) Sep 20, 2015
Dark Matter is what the Fabric of Space is made of. Dark Energy is the Energy of Time. Both are here in our universe but in such a way that we cannot put our fingers on them and out of reach of instruments made of mater to measure energy.

Everything else exists in this Space-Time membrane environment made of these other things.

The units are likely subject to the same E=Mc2 type values however with some other constant.. DE=DMc2 and at a much smaller scale... where a neutrino may be the size of a basketball or even the size of the sun
Benni
2.7 / 5 (7) Sep 20, 2015
Tell us more about your close friend Einstein and GR. Does GR involve DE?
No one knows so much about this subject as you!
Fortunately you post regular updates on phys.org.
Einstein foresaw DM theory already in 1916 and decided not to go along.
Just like you, Benni.


.....then I can only conclude that Einstein was not only a lot smarter than Zwickey, but also yourself.

First learn to spell the names of the great scientist you compare yourself with.
You sloppy narcissist!
In order to know who is the smartest between Einstein, Zwicky and me, you would have to be as smart as you think you are, but you are not.


.....and still no science, just the usual name calling & vulgarity amply indicative of your comprehension of science.

Here's an idea for you, drill down into some of those Partial DEs in Einstein's GR & let us know what you've come up with, that would be some real science about which all of us could have some interesting discussions.
Noumenon
4.2 / 5 (5) Sep 20, 2015
Dark Matter is what the Fabric of Space is made of. Dark Energy is the Energy of Time. Both are here in our universe but in such a way that we cannot put our fingers on them and out of reach of instruments made of mater to measure energy.


Your ball-of-string in the shed needs a little help; It has been proposed that DE (not DM) is proportional to the space-time metric which is compatible with general relativity as an added term, the cosmological constant. It is true that DM does not give off electromagnetism so is out of reach of instruments that make use of it,.... however it must have mass and so must be gravitational. This opens the door to instruments that are based on those conditions.

Benni
2.7 / 5 (7) Sep 20, 2015
,.... however it must have mass and so must be gravitational. This opens the door to instruments that are based on those conditions.


Odd isn't it, how NASA navigates spacecraft all over the solar from Mercury & all the way to Pluto & beyond using the Inverse Square Law of Newtonian Gravity.

Just think, if NASA had calculated the Pluto flyby to account for 75-90% more gravity to account for "missing mass", just how well do you think that flyby would have worked?

DM Enthusiasts simply do not comprehend the "gravity" of the problems they create with the "missing mass" hypotheses. It is a massive comprehension problem whereby they fail to comprehend that "local physics" of the Universe is the same physics that governs the "distant physics" of the Universe. Entropy of the Universe is the same in our galaxy as in one 10Gyrs away.
Noumenon
3.9 / 5 (7) Sep 20, 2015
Just think, if NASA had calculated the Pluto flyby to account for 75-90% more gravity to account for "missing mass", just how well do you think that flyby would have worked?


It appears that you don't comprehend the shear difference in volumetric scale between our solar system space and that surrounding galaxies and galaxy clusters for which DM was proposed.

It could very well be that the issue is one of theory for the same reason of scale. However, it would be foolish to jump to this conclusion without first ruling out the presence of DM,... after all, GR did correctly predict the perihelion of mercury while Newtons did not [not suggesting that GR is needed for DM]
carlo_piantini
3 / 5 (2) Sep 20, 2015
So Newton was wrong and space is not a vacuum...Any university teaching such material should immediately lose its funding and status.

Are you suggesting that any university that teaches its students about the heliosphere, or the solar wind, or the plasma that is ejected into interstellar space via CMEs or solar flares, should lose its funding and status? You're talking about every university in the world, dude. Interstellar space is *not* a vacuum, it is very much filled with plasma. I'm not sure what you're talking about...

Magnetic fields do not rotate.

https://en.wikipe...nt_sheet
"The shape of the current sheet results from the influence of the Sun's rotating magnetic field on the plasma in the interplanetary medium (Solar Wind).[4] A small electrical current flows within the sheet, about 10−10 A/m². The thickness of the current sheet is about 10,000 km near the orbit of the Earth."
carlo_piantini
3.7 / 5 (3) Sep 20, 2015
Also, rotating magnetic fields are an extremely common and critical piece of the world's electrical infrastructure. They're used by every alternating current motor and generator in the world. The phenomena was discovered and engineered by Nikola Tesla in 1882 (allegedly), subsequently discovered by Ferraris in '85, and then patented by Tesla in '88. Supposedly, Tesla discovered the concept while watching the Sun set, ironically enough.

https://en.wikipe...ic_field
Benni
2.5 / 5 (8) Sep 20, 2015
Just think, if NASA had calculated the Pluto flyby to account for 75-90% more gravity to account for "missing mass", just how well do you think that flyby would have worked?


It appears that you don't comprehend the shear difference in volumetric scale between our solar system space and that surrounding galaxies and galaxy clusters for which DM was proposed.


Why do you imagine this makes a difference? The challenge for DM Enthusiasts must be to prove there are different physics at work at many different areas of the Universe than what is proven to be the case within our solar system. Can you do this?

It could very well be that the issue is one of theory for the same reason of scale
????

However, it would be foolish to jump to this conclusion without first ruling out the presence of DM
Better called putting the cart before the horse. Why not just throw in additional fudge factors just to be sure every unanticipated unknown is covered?


Noumenon
4 / 5 (8) Sep 20, 2015
The challenge for DM Enthusiasts must be to prove there are different physics at work at many different areas of the Universe than what is proven to be the case within our solar system. Can you do this?


Actually the opposite is the case. The premise of the proposition of DM is that the physics is assumed to be the same.

Why do you imagine [difference in volumetric scale between our solar system space and that surrounding galaxies] makes a difference?

Because of the density of DM in the solar system.

nevermark
3.9 / 5 (7) Sep 20, 2015
What is perceived as dark matter is simply gravitational energy [...] That is the simple explanation without all the big words.


Wow, a "simple" explanation without "big words", equations, data, verifiable predictions, or any other science.

In the meantime, scientists continue trying out a wide variety of explanations in pursuit of understanding measurable effects (for 70 years) that don't yet have a verifiable explanation. And getting criticized for their search by the ignorati.
Benni
2.2 / 5 (10) Sep 20, 2015
The challenge for DM Enthusiasts must be to prove there are different physics at work at many different areas of the Universe than what is proven to be the case within our solar system. Can you do this?


Actually the opposite is the case. The premise of the proposition of DM is that the physics is assumed to be the same.
So, according to this hypothesis, NASA scientists are calculating gravity wrong when they send spacecraft to all points of our solar system. By default NASA scientists are miscalculating solar system gravity by an amount of 75 to 90% divided by 10 to 25%. This must be the case if "the physics is assumed to be the same".

Why do you imagine difference in volumetric scale between our solar system space and that surrounding galaxies makes a difference?

Because of the density of DM in the solar system.
.....and that is what? With 75-90% of the solar system missing based on measured gravitational fields NASA is unable to account for?
Noumenon
4.2 / 5 (10) Sep 20, 2015
I see my link did not work. Here, it is again. The density of DM obviously must be negligible in the solar system,... which is but a speck in comparison to an entire galaxy. Why are you assuming that DM is homogeneous in the universes?
Benni
2.5 / 5 (8) Sep 20, 2015
I see my link did not work. http://arxiv.org/...06.5534, it is again. The density of DM obviously must be negligible in the solar system


Of course it's obviously negligible in the solar system, in fact the number they use is so pathetically low that it falls well inside any statistical margin of error no matter how tight you make it. It's the reason NASA uses the Inverse Square Law applied to Newtonian Gravity when sending spacecraft all around the solar system.

Why are you assuming that DM is homogeneous in the universes?


You mean there's some reason I shouldn't? If there is, how would you know that? Are you suggesting the exact opposite of the author regarding the article under discussion that DM is found only in envelopes around Spiral Galaxies?

The author of this article suggests DM is also found inside our Sun, quite contrary to what Zwickey proposed for holding Spiral Galaxies together. Now we need it to hold our Sun together?

docile
Sep 20, 2015
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docile
Sep 20, 2015
This comment has been removed by a moderator.
docile
Sep 20, 2015
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Benni
2 / 5 (4) Sep 20, 2015
Ok docile......so let's get this whole thing about our Sun & DM boiled down to a number to which the Einstein Field Equations can be applied. What percent of the Sun do you propose is made up of DM?
docile
Sep 20, 2015
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Benni
2.6 / 5 (5) Sep 20, 2015
The dark matter works in exactly the opposite way, which the EFE's are expecting. The EFE's are based on equivalence principle, whereas the DM violates the equivalence principle heavily. It's lensing is significantly higher, than its gravitational attraction to normal matter (which is distance dependent in addition). And the dark matter is repulsive by itself, i.e. it has negative charge of gravity and imaginary mass by itself. Lets say, that the dark matter contributes with 90% to gravitational lensing of solar core, but its inertial mass accounts only to 7 - 10% to solar core inertia and 60 - 70% to its rotational momentum. When the scientists are saying, that the dark matter is five times heavier than the visible matter inside the universe, they just mean with it its gravitational lensing - no less, no more.


What I understand from all the above is that you wouldn't answer a simple question. Again, what % of the Sun's mass do you claim is DM?
docile
Sep 20, 2015
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Benni
2.6 / 5 (5) Sep 21, 2015
Which mass do you mean?
Repeating it again, DM "mass".

normal matter the mass can be defined/measured with gravitational lensing, gravitational attraction/acceleration,
For sure the visible matter of the Sun creates gravitational lensing, Einstein in GR did the exact calculation for that based on the content of visible matter of the Sun.

At the case of dark matter all these quantities differ each other
You could only know this if you've isolated some DM to quantify or you wouldn't be able to determine that there are quantities of DM which differ from one another . When & how did you do this?

In addition, the Sun core contains dark matter of different kind than its perimeter
There's more than one kind of DM? Describe the atomic structures of these different kinds of DM that you know so much about.

These quantities are distance dependent
How did you measure this distance?
liquidspacetime
1 / 5 (1) Sep 21, 2015
What physics mistakes for the density of the dark matter is actually the state of displacement of the dark matter.

Particles of matter move through and displace the dark matter, including 'particles' as large as galaxies and galaxy clusters.

'The Milky Way's dark matter halo appears to be lopsided'
http://arxiv.org/abs/0903.3802

"the emerging picture of the dark matter halo of the Milky Way is dominantly lopsided in nature."

The Milky Way's halo is lopsided due to the matter in the Milky Way moving through and displacing the dark matter, analogous to a submarine moving through and displacing the water.

The Milky Way's halo is the state of displacement of the dark matter.

The Milky Way moves through and curves spacetime.

The Milky Way's halo is curved spacetime.

The state of displacement of the dark matter is curved spacetime.

The state of displacement of the dark matter *is* gravity.
EnsignFlandry
not rated yet Sep 21, 2015
Dark Matter is what the Fabric of Space is made of. Dark Energy is the Energy of Time. Both are here in our universe but in such a way that we cannot put our fingers on them and out of reach of instruments made of mater to measure energy.

Everything else exists in this Space-Time membrane environment made of these other things.

The units are likely subject to the same E=Mc2 type values however with some other constant.. DE=DMc2 and at a much smaller scale... where a neutrino may be the size of a basketball or even the size of the sun


Glad that is cleared up.
baudrunner
not rated yet Sep 22, 2015
Dark Matter? In stars, where the only matter there is so sub-nuclear and plastic that it doesn't even constitute matter as we define it yet? So - "Dark Plasma", maybe? Really. Readers should be reminded that the existence of some kind of DM, or DE, was inferred from observing gravitational behavior between galaxies and galactic clusters at great distances. Additional theories just grew and sprouted from that.

Three possible contributors to the DM illusion:
1. The behavior of quark pairs is such that the attractive force between them increases with the distance between them. It is probably so for bodies in space and the gravitational potential between them.
2. Helium is the second most abundant element in the Universe. It is so inert that it does not contribute to the propagation of photonic waves. Hence, it is dark matter, isn't it?
3. Over large distances, photonic waves red shift, even when emanated from a static luminescent body which isn't accelerating.

DM
balslev
1 / 5 (1) Sep 22, 2015
Since the Big Bang according to FinalTheories took place in an existing closed Euclidean Universe, the "old" matter in the neighbourhood of the Big Bang will act as accumulation points for the generation of new stars. This entails that there will be a form for dark matter in the centre of the stars.
charlimopps
3 / 5 (4) Sep 23, 2015
Man, I've gotta seriously laugh at the rating bias on this site sometimes. Recount the historical development of Descartes theory, and Newton's opposition to it in favor of gravitation? 1-Star for you. Point out that Descrates' physical premise was undeniably right, and Newton's was undeniably wrong? 1-Star. Mention that a scientific experiment has spent over a decade making failed attempts to detect axions from the Sun, with a provided link? 1-Star.

But yeah, there's no bias happening on this site at all...


We're biased against obvious pseudoscience. Sorry man... stop being wrong and you'll get more upvotes.
Scroofinator
not rated yet Sep 24, 2015
We're biased against obvious pseudoscience. Sorry man... stop being wrong and you'll get more upvotes.

There is no physical evidence of DM/DE, and the science is not even remotely sound so how do you KNOW that he's wrong. That's more cranktastic then questioning the current theories. Essentially we're commenting on a pseudoscience article, so check that hypocrisy.
docile
Sep 25, 2015
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