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Thread: Where is the "Dark Matter" in the Milky Way?

  1. #1 Where is the "Dark Matter" in the Milky Way? 
    Moderator Moderator Dishmaster's Avatar
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    A new study sheds serious doubts on the current understanding of gravitational phenomena caused by the hypothetical "Dark Matter". Thorough measurements obviously demonstrate that the movements of stars in the local solar neighbourhood in the Milky Way up to a radius of 4 kpc (half way to the Galacatic Centre) can be explained without any Dark Matter. However, the current paradigm explains the rotation curve of the Milky Way and other galaxies by the presence of the spherically symmetric halo of Dark Matter.

    See on-line article:
    ESO - eso1217 - Serious Blow to Dark Matter Theories?


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    Maybe it has special shape, that's the only alternative they proposed.


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    Quote Originally Posted by Dishmaster View Post
    A new study sheds serious doubts on the current understanding of gravitational phenomena caused by the hypothetical "Dark Matter". Thorough measurements obviously demonstrate that the movements of stars in the local solar neighbourhood in the Milky Way up to a radius of 4 kpc (half way to the Galacatic Centre) can be explained without any Dark Matter. However, the current paradigm explains the rotation curve of the Milky Way and other galaxies by the presence of the spherically symmetric halo of Dark Matter.

    See on-line article:
    ESO - eso1217 - Serious Blow to Dark Matter Theories?
    A spatial shape to it that does not include our solar system is one idea, another is that this study could be mistaken and that dark matter will be found locally, or dark matter exists but does not behave as we expect it to, or maybe dark matter is not matter at all but instead a motive aether that is the source of all gravity and extended lensing, or that Newtonian gravity and GR are not relevant at this scale so another model of gravity such as MOND needs to step to the plate and dark matter does not exist, or ??
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    Quote Originally Posted by forrest noble View Post
    A spatial shape to it that does not include our solar system is one idea, ...
    Yes, I know, but I find it difficult to believe for mainly two reasons.

    1) As far as I remember, one of the reasons Dark Matter was postulated were galaxy formation models that showed that a 1D spherical distribution of matter (a halo) is needed to keep the spiral structures stable. If this is not true anymore, then this is more an argument against Dark Matter than for it.

    2) A fluid, i.e. a matter that only interacts by gravitation and maybe collisions, should quickly attain a distribution that is governed by equilibrium of gravitational and centrifugal forces. Anything else than a spheroid would be hard to explain in my view. One would have to investigate how much gravitational drag/viscosity forces may play a role here. We know that active galaxies have strong winds that deplete them of their gas. Maybe, if the gravitational drag is strong enough, Dark Matter might be lost during such events.

    But indeed, it is no secret that I would not be surprised, if it turned out that a modification of the gravitational laws as we know them must be taken into account. It is a pity that those possibilities have such a weak lobby compared to the Dark Matter hypothesis.
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    I was wondering what a 1D halo would look like (a line?). Did you mean a 3D torus? In any case, from what I recall, a sphere extending past the luminous matter (disk or ellipse) is what is theorized.

    A thought from my head. The prevailing hypothesis is that the Milky Way is created by the merger of many smaller galaxies, in which the smaller galaxies normal matter is ripped apart and "eaten" or absorbed. There's very good evidence for this. That interaction ruled not only by gravity, but collisional interactions of the gas included in the galaxies.

    However, it would take much longer for the dark matter spheroids to smoothly merge, since there are no collisional effects to "quickly" remove the momentum from the dark matter. (See the Bullet Cluster). Therefore it would take much longer for that merger to take place, so one would expect DM to not be homogenous. While the overall effect might be that of a "perfect" sphere, on smaller scales it might be quite lumpy within a specific galaxy for tens of billions of years post merger.

    MW
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    If I have this right, the survey was looking for changes in velocity of 400 stars over time?
    They found that the velocities are more constant than expected.
    I have seen a few similar coments coming from planet hunting efforts, using gravitaional methods. (long term correction seem small)

    If we are in a moderately low surface brightness galaxy and we can detect any dark matter this is a big deal.
    Unless, it is another faster than light *********.


    From the notes at the bottom of the article:
    Theories predict that the average amount of dark matter in the Sun’s part of the galaxy should be in the range 0.4-1.0 kilograms of dark matter in a volume the size of the Earth. The new measurements find 0.00±0.07 kilograms of dark matter in a volume the size of the Earth.
    It looks like they are finding nothing extra effecting the motion of these 400 stars, no indications of MOND either.

    If I have the numbers right, then these stars have paths 5 - 8 times straighter than expected.

    My guess would be the assumption that gallaxies rotate nicely is wrong, and they are all growing.
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    They chose exclusively 400 red giant stars for their survey. Perhaps the obvious question is that they may have discovered something about the mass of these stars that we did not previously know? It took decades to confirm evidence of the neutrino. Hopefully, the Large Hadron Collider will discover some DM (or not).
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    Quote Originally Posted by Dishmaster View Post
    Quote Originally Posted by forrest noble View Post
    A spatial shape to it that does not include our solar system is one idea, ...
    Yes, I know, but I find it difficult to believe for mainly two reasons.
    1) As far as I remember, one of the reasons Dark Matter was postulated were galaxy formation models that showed that a 1D spherical distribution of matter (a halo) is needed to keep the spiral structures stable. If this is not true anymore, then this is more an argument against Dark Matter than for it.
    Yes, but those now considering an Amercan football shape to our galaxy's dark matter, must believe this idea is possible.

    2) .......We know that active galaxies have strong winds that deplete them of their gas. Maybe, if the gravitational drag is strong enough, Dark Matter might be lost during such events.
    This part of your analysis in 2) would be an argument in favor of the possibility of dark matter, right? If it were preceded by a statement such as "only in the very unlikely possibility...." or similar wording, would it be an argument of doubt concerning the existence of dark matter.

    But indeed, it is no secret that I would not be surprised, if it turned out that a modification of the gravitational laws as we know them must be taken into account. It is a pity that those possibilities have such a weak lobby compared to the Dark Matter hypothesis.
    Alternative models in all aspects of science represent a "weak lobby," mainly because the number of theorists that support them are few. Also, there is no generally known mathematical alternative model of gravity that seems to be able to presently answer all the questions concerning all venues of gravitational influences. Milgram's MOND does well in spiral galaxy predictions but requires ad hoc variables in other venues that seemingly is like adding dark matter to the standard equations.
    //
    Last edited by forrest noble; April 23rd, 2012 at 01:12 PM.
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    MeteorWayne,

    Concerning Dishmaster quote:

    I was wondering what a 1D halo would look like (a line?). Did you mean a 3D torus?
    What I think Dishmaster meant is one dimensional in the verbal sense rather than in the mathematical sense, his meaning being a generally spherical halo.
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    If neutrinos have non-zero mass (whatever mass is ) and if theres a lot of them widely distributed in the galaxy, could their mass have no observable effect in a local context but have an effect on a large galactic scale? Could you have unseen massive clouds of neutrinos spinning around black holes?
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    PetTastic said that the gravity measurement is totally normal (totally normal around our sun)... so no dark matter and no gravity theory possible around our sun. So, probably the idea that the dark matter (or something) clumping near the black hole instead is better? (I dunno)
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    Quote Originally Posted by msafwan View Post
    PetTastic said that the gravity measurement is totally normal (totally normal around our sun)... so no dark matter and no gravity theory possible around our sun.
    Dark matter is not needed for gravitational predictions in our solar system in that Newtonian gravity works very well, and GR works even better. Any overall gravity model would need to calculate like GR in the solar system having close-to-zero variation from Newtonian gravity, then it must justify larger variables at the galactic scale, and then justify different variables again at the scale of galaxy clusters and super-clusters. Another gravity model might be able do this without the inclusion of dark matter or adding ad hoc variables at the cluster scale like MOND, but none have been able to do this successfully so far. We have separate equations that when combined can calculate in all venues (like Newton, GR, MOND, etc.), but they cannot all be put together in a single justifiable model without dark matter or dark-matter-like variables.

    So, probably the idea that the dark matter (or something) clumping near the black hole instead is better? (I dunno)
    Whether we use Newtonian gravity or GR, we need to extend a dark matter halo out many times greater than the diameter of the galaxy for calculations to come out close concerning the stellar orbital velocities being observed.
    //
    Last edited by forrest noble; April 24th, 2012 at 11:17 AM.
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    How come we can't see dark matter in its part? why it need the whole galaxy/cluster to prove dark matter exist? Can it possibilty not fundamental entity but instead an emergent behaviour of complex interaction between star system? (I dunno, maybe rotational, radiation flux, radiation pressure, stuff, stuff, magnetic or something? maybe it explain why dark matter couldn't be observed individually? like "the sum is greater than the part" <- emergent behaviour)
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    Quote Originally Posted by msafwan View Post
    How come we can't see dark matter in its part? why it need the whole galaxy/cluster to prove dark matter exist? Can it possibilty not fundamental entity but instead an emergent behaviour of complex interaction between star system? (I dunno, maybe rotational, radiation flux, radiation pressure, stuff, stuff, magnetic or something? maybe it explain why dark matter couldn't be observed individually? like "the sum is greater than the part" <- emergent behaviour)
    We cannot observe dark matter anywhere, just the inference of it based upon unseen gravitational influences. We are fairly certain something is there, but even to call it matter would be an assumption that only additional matter can influence light and other matter to the extent that we have observed.
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    I thinnk this "dark matter" should be found i sub Quark level where where have only scarse understanding of the mechanisms, even the understanding of Higgs Field may also reside there.

    The Quantum Entanglement to my understanding can't be explained by ordinary Quantum Mechanics, and to my unscientific understanding be related to a supplementary "force" a bit similar to gravity and magnetism.
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    Does cosmologist always just look at problem from the fundamentals (quark/string/higgs field)? What if dark matter arise from complex interaction, nothing to do with fundamental physics? for example: look at Pioneer anomaly: it wasn't any fancy fundamental theory of gravity that explain it but a complex interaction between power source decay, electronic placement, power system degradation and the spacecraft orientation that matter... very complex stuff & took computer simulation to replicate (and yet can easily be mistaken for proof of modified theory of gravity).

    And look at a simple lever... it is physic but there's no link to particle physic at all... the lever work because of its shape, geometry, material rigidity, and distance from fulcrum... not the tiniest physics (quark/string/field) whatsoever...

    And also look at high temperature superconductivity... it has nothing do to with particle physic at all, what it takes is just a perfect atomic arrangement and *voila* superconductivity... miracles!
    Last edited by msafwan; April 24th, 2012 at 12:11 AM.
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    How does this effect MOND?
    Is 13k lightyears below the disk far enough for MOND to show up?

    The rotation curves of galaxies already deviate strongly from predicted at 15 to 20k lightyear out from the centre, so my guess is MOND should be detectable.

    You can't have lumpy MOND

    Any thoughts?
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    Good point. Dark matter IS lumpy (again, see the Bullet cluster), whatever the heck it is.
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    Quote Originally Posted by HexHammer View Post
    I think this "dark matter" should be found in sub Quark level where we have only scarce understanding of the mechanisms, even the understanding of Higgs Field may also reside there.
    Yes, this has been one of the considered answers. Once we go down to the quantum level concerning particles/ particulates size not only may individual particles not singularly be detectable, but as a whole it might behave more like fluid than clouds of particulates and might rightfully be called an aether.

    The Quantum Entanglement to my understanding can't be explained by ordinary Quantum Mechanics, and to my unscientific understanding be related to a supplementary "force" a bit similar to gravity and magnetism.
    I also think you are on the right tract thinking that gravity and magnetism are not really understood today at a fundamental level, and realizing that Quantum Entanglement is a phenomena that is also not understood. With such a quantum-scale particulate field (which might bring back the aether idea) all of modern physics might be more easily understood and explained because then there would be an omnipresent medium and background of particulates comprising the ZPF that could conceivably mechanically and simply explain phenomena such as gravity, magnetism, the cause of mass, quantum entanglement, the double slit experiment, etc.

    Your idea might be valid but that would make dark matter even more difficult to find. It might be like searching for the aether all over again.
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    Quote Originally Posted by PetTastic View Post
    How does this effect MOND?
    Is 13k lightyears below the disk far enough for MOND to show up?

    The rotation curves of galaxies already deviate strongly from predicted at 15 to 20k lightyear out from the centre, so my guess is MOND should be detectable.

    You can't have lumpy MOND
    Any thoughts?
    You are correct. Milgram's MOND is simply a mathematical model like Newton's or GR. None propose dark matter or lumpiness. MOND was formulated to eliminate the need for dark matter in the first place. You could add dark matter to MOND and make better predictions at the galactic and super-galactic scales. But this would defeat the purpose of MOND in the first place.

    Many now believe in the lumpiness of dark matter and that it is not evenly distributed in all galaxies, clusters, etc. nor can its distribution by accurately predicted prior to observations. Many predictions might seem like quantum mechanics in that there are different possibilities beforehand concerning what might be observed.
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    Quote Originally Posted by forrest noble View Post
    Your idea might be valid but that would make dark matter even more difficult to find. It might be like searching for the aether all over again.
    While we'r at it, I havn't been able to find much data about Magnetars and it's contribution on keeping the galaxy together, any who can conjour up a good article?

    As I understand it, Magnetars might be 1 of the most contributing factors of being "galaxy mortar".
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    Your understanding is incorrect. They contribute nothing to keeping galaxies together. They are just neutron stars with strong magnetic fields. Since gravity is what holds a galaxy together, they add nothing special other than their mass, just like any other star.
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    Quote Originally Posted by MeteorWayne View Post
    Your understanding is incorrect. They contribute nothing to keeping galaxies together. They are just neutron stars with strong magnetic fields. Since gravity is what holds a galaxy together, they add nothing special other than their mass, just like any other star.
    That's strange, in various stars there are metals which should be fairly magnetic, also in various nebulae where the metal has been scatterd it should be sensetive to magnetism.

    Besides, I don't understand your statement can contradict the search for "Dark Matter", because gravity in various Galaxy models isn't sufficient to keep it together, and would disperse with current understanding of gravity.
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    There appears to be much you do not understand grasshopper.
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    Quote Originally Posted by HexHammer View Post
    That's strange, in various stars there are metals which should be fairly magnetic, also in various nebulae where the metal has been scatterd it should be sensetive to magnetism.
    there's only 3 metals that are magnetic at room temperature : iron, nickel and cobalt
    and guess what ? none of them are magnetic at elevated temperatures, like the ones existing in stars
    hence any magnetism involved in neutron stars can't be due to metals (who don't exist in a neutron star anyway)
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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    Quote Originally Posted by marnixR View Post
    Quote Originally Posted by HexHammer View Post
    That's strange, in various stars there are metals which should be fairly magnetic, also in various nebulae where the metal has been scatterd it should be sensetive to magnetism.
    there's only 3 metals that are magnetic at room temperature : iron, nickel and cobalt
    and guess what ? none of them are magnetic at elevated temperatures, like the ones existing in stars
    hence any magnetism involved in neutron stars can't be due to metals (who don't exist in a neutron star anyway)
    The plasma makes a magnetic field in stars? Or whatever it is.

    Magnetars are a variant of neutron stars, oridnary neutrons stars are to my understanding not magnetic like a magnetar.
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    Ordinary neutron stars (made mostly of neutrons, BTW, so it's not a plasma) have weak magnetic fields. Magnatars have strong magnetic fields. They are rare, with only a few dozen known. In the observable Universe.
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    Quote Originally Posted by MeteorWayne View Post
    Ordinary neutron stars (made mostly of neutrons, BTW, so it's not a plasma) have weak magnetic fields. Magnatars have strong magnetic fields. They are rare, with only a few dozen known. In the observable Universe.
    I'm talkinga bout 2 things here.

    - ordinary suns which plasma to my understanding should generate magnetism, thus a magnetism field.

    - Magnetar, a variant of Neutron stars.

    So the question is, how much will these magnetic fields from respectivly suns and magnetars affect eachother?
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    Not at all. Stars are not close enough to each other (except in extremely rare circumstances) for the strength of their fields to be measurable from each other. Before you ask, we don't detect magnatar's magnetic fields by measuring the field strength directly here on good ol' earth.
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    When is the next survey of this type due?

    There is Gaia launching next year, that is monitoring star motions over a five years.
    There must be lots of data available from planet hunters looking for gravitational wobbles.
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    Dark matter bashing seems to be becoming quite popular.

    This one claims to kill it off at the near galatic cluster scale.
    More doubt cast on dark matter theories | TG Daily
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    Quote Originally Posted by PetTastic View Post
    Dark matter bashing seems to be becoming quite popular.

    This one claims to kill it off at the near galatic cluster scale.
    More doubt cast on dark matter theories | TG Daily
    A slightly more detailed description of this work here: Newly Discovered Satellite Galaxies: Another Blow Against Dark Matter?
    ei incumbit probatio qui dicit, non qui negat
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    Do the Milky Way
    Our model appears to rule out the presence of dark matter in the universe, threatening a central pillar of current cosmological theory. We see this as the beginning of a paradigm shift, one that will ultimately lead us to a new understanding of the universe we inhabit.
    Strong wording for a Royal Astronomical Society page
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    I don't understand... how does this mega structure explain why our galaxy rotate faster than it should be (without flying apart)??
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    Quote Originally Posted by HexHammer View Post
    Quote Originally Posted by forrest noble View Post
    Your idea might be valid but that would make dark matter even more difficult to find. It might be like searching for the aether all over again.
    While we'r at it, I havn't been able to find much data about Magnetars and it's contribution on keeping the galaxy together, any who can conjour up a good article?

    As I understand it, Magnetars might be 1 of the most contributing factors of being "galaxy mortar".
    There are a couple of cosmological models that do propose that electricity (charged particle currents) and/or magnetism contribute to the form/ appearance of galaxies in general. One model is called Plasma Cosmology, and another similar version is called the Electric Universe. To my knowledge none of these models, however, propose that Magnetars contribute much to the general appearance of galaxies since Magnetars are rare and distances between stars are so great.
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    Quote Originally Posted by msafwan View Post
    I don't understand... how does this mega structure explain why our galaxy rotate faster than it should be (without flying apart)??
    I don't think it explains anything.

    It just does not fit the current dark matter models.
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    Quote Originally Posted by forrest noble View Post
    There are a couple of cosmological models that do propose that electricity (charged particle currents) and/or magnetism contribute to the form/ appearance of galaxies in general. One model is called Plasma Cosmology, and another similar version is called the Electric Universe. To my knowledge none of these models, however, propose that Magnetars contribute much to the general appearance of galaxies since Magnetars are rare and distances between stars are so great.
    Personally I think modern science grossly underestimate Magnetars, as we all should know that magnetism is far far stronger that gravity.
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    Quote Originally Posted by MeteorWayne View Post
    A thought from my head. The prevailing hypothesis is that the Milky Way is created by the merger of many smaller galaxies, in which the smaller galaxies normal matter is ripped apart and "eaten" or absorbed. There's very good evidence for this. That interaction ruled not only by gravity, but collisional interactions of the gas included in the galaxies.

    However, it would take much longer for the dark matter spheroids to smoothly merge, since there are no collisional effects to "quickly" remove the momentum from the dark matter. (See the Bullet Cluster). Therefore it would take much longer for that merger to take place, so one would expect DM to not be homogenous. While the overall effect might be that of a "perfect" sphere, on smaller scales it might be quite lumpy within a specific galaxy for tens of billions of years post merger.

    MW
    I would tend to agree with you that something like this could be closer to the heart of the problem.

    We have observational evidence of gravitational lensing, a prediction of general relativity. We see multiple and often distorted images of a background galaxy, around a gravitational source that lies (presumably) directly between us and that background galaxy.

    We also have observational evidence, from this gravitational lensing, that if general relativity is correct, there is more matter in clusters of galaxies than the matter we can see. So either general relativity is wrong, or there is more matter in those clusters of galaxies than we can see. Hence the need for "dark matter", whatever that term turns out to represent.

    We also have observational evidence in places like the Bullet Cluster and MACS J0025.4-1222, that these "extra" effects of gravitational lensing do not necessarily stay with the concentrations of matter when they collide - the dark matter is somewhat separated from the normal matter.

    If there is no dark matter, whatever it is, then an alternative theory of gravity is going to have to come up with a way to explain how gravitational lensing seems to show a gravitational effect that can apparently be separated from normal matter.
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    Quote Originally Posted by HexHammer View Post
    Quote Originally Posted by forrest noble View Post
    There are a couple of cosmological models that do propose that electricity (charged particle currents) and/or magnetism contribute to the form/ appearance of galaxies in general. One model is called Plasma Cosmology, and another similar version is called the Electric Universe. To my knowledge none of these models, however, propose that Magnetars contribute much to the general appearance of galaxies since Magnetars are rare and distances between stars are so great.
    Personally I think modern science grossly underestimate Magnetars, as we all should know that magnetism is far far stronger that gravity.
    So modern science underestimates the improtance of something you don't understand yourself?
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    Quote Originally Posted by HexHammer View Post
    Personally I think modern science grossly underestimate Magnetars, as we all should know that magnetism is far far stronger that gravity.
    So who told you about magnetism? Scientists.
    Who told you about gravity? Scientists.
    Who told you about magnetars? Scientists.

    If you think they have got things so wrong, maybe magnetism isn't "far far stronger than gravity".
    If you think they have got things so wrong, maybe magnetars don't exist.

    Are you just picking and choosing which bits of science you want to be right based on a whim?
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    Why can't dark-matter only exist in galaxies but not in solar system and not in universe's mega-structure and also not in anywhere else except in galaxies? If you say dark matter is everywhere then someone will says that the mega-structure doesn't need dark matter (a downer) and "no dark matter detected around our solar system" (another downer), but if someone says dark matter exist in a galaxies (as a property of a galaxy) then the halo effect from bullet cluster collision prove that this is true (positive). -Is dark matter need to be everywhere at all (is a requirement?)???

    Isn't this a major discovery discovering that dark matter maybe a special property of a galaxy??
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    1. Observation evidence for dark matter
    1) Galactic rotation curves
    2) Galaxy clusters and gravitational lensing
    3) WMAP
    4) Bullet cluster
    5) Structure formation

    2. In the Galaxy, No evidence for dark matter
    1) At the Earth : non-observation(Xenon100, CDMS-II...)

    2) At the solar system : non-observation

    3) At the center of galaxies : no evidence
    Greedy Supermassive Black Holes Dislike Dark Matter
    http://www.universetoday.com/13091
    Astronomers Find Black Holes Do Not Absorb Dark Matter
    http://www.universetoday.com/60422

    4) At the galactic plane : no evidence
    "No evidence for a dark matter disk within 4 kpc from the galactic plane"
    http://arxiv.org/abs/1011.1289v1.pdf

    5) At the galactic halo : no evidence
    Globular Cluster problem
    "Evidence Against Dark Matter Halos Surrounding the Globular Clusters MGC1 and NGC 2419"
    http://arxiv.org/abs/1010.5783

    3. Negative energy(mass) hypothesis
    It is simply explained.
    Dark matter which has negative mass is clustered around galaxy. And centripetal force effect exist in the galaxy from dark matter halo out of the galaxy.



    [ Centripetal force effect in the galaxy from dark matter(negative mass) halo out of the galaxy ]

    ** Computer Simulation **
    http://www.youtube.com/watch?feature=player_detailpage&v=SRUqQM2FfNU#t=81 1s
    please see to 13m 34s

    If the negative mass is disposed at the outline, the test mass vibrates, and a kind of restoring force (This corresponds to the centripetal force when considering rotation of the galaxy) exists.

    This suggests that the halo, dark matter (negative mass) of the external Galaxy could get additional effects of centripetal force to the inner Galaxy.
    According to “The motions of negative mass and positive mass,” that we have examined above, when the absolute value of positive mass is bigger than that of negative mass, there exists the attractive effect between positive mass and negative mass, so the negative mass becomes clustered around the massive positive mass.
    Currently, negative mass is distributed usually around outside the galaxy, the clustering phenomenon (or Gravitational Lensing effect) of negative mass (dark matter) occurs in galaxy or at the level of cluster of galaxies.

    The explanations above provide explanations about very strange characteristics related to those of dark matter. Dark matter that is consisted of negative mass usually spreads outside the galaxy, so it is observed that it becomes clustered around galaxy or clusters of galaxies that are consisted of positive mass. On the other hand, since it barely exists inside the galaxy, it doesn’t show becoming clustered around Earth, or any objects in the solar system and galaxy, and yet, we can know that it still generates the effect of additional centripetal force on objects within the galaxy.

    1. Computer simulation1. Dark energy - Accelerating expansion of universe due to negative mass
    Dark energy - Accelerating expansion of distant galaxy due to negative mass -1 - YouTube

    2. Computer simulation2. Inflation, decelerating expansion and accelerating expansion with pair creation of negative mass and positive mass
    Inflation, accelerating expansion with pair creation of negative and positive mass -2 - YouTube


    3. Paper: The change of Gravitational Potential Energy and Dark Energy in the Zero Energy Universe.
    viXra.org e-Print archive, viXra:1110.0019, The Change of Gravitational Potential Energy and Dark Energy in the Zero Energy Universe
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    Ups double post! ><
    Last edited by HexHammer; April 26th, 2012 at 12:02 AM.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by HexHammer View Post
    Personally I think modern science grossly underestimate Magnetars, as we all should know that magnetism is far far stronger that gravity.
    So who told you about magnetism? Scientists.
    Who told you about gravity? Scientists.
    Who told you about magnetars? Scientists.

    If you think they have got things so wrong, maybe magnetism isn't "far far stronger than gravity".
    If you think they have got things so wrong, maybe magnetars don't exist.

    Are you just picking and choosing which bits of science you want to be right based on a whim?
    Surely you are jesting!

    Even a non scientists would know that, just take an ordinary fridge magnet and attaract some iron, then that tiny magnet will counter the entire Eearth's gravity.

    Simple!

    27:29 "billions and billions times stronger" Einstein's Dream - The Elegant Universe - PBS NOVA - YouTube
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    Quote Originally Posted by HexHammer View Post
    Even a non scientists would know that, just take an ordinary fridge magnet and attaract some iron, then that tiny magnet will counter the entire Eearth's gravity.

    Simple!
    Try that at a distance of more than a few inches or cm and gravity wins.
    Even the powerful pulling force of magnets used to lift cars in junk yards can't be even detected at the distance of a few yards.
    There is no detectable effect when flying a metal plane over the north pole.

    In space magnetic fields are purely a pushing force. Firing material away from the surface of stars at thousands of km/s.
    I believe in nothing, but trust gravity to hold me down and the electromagnetic force to stop me falling through
    Physics is the search for the best model not the truth, as only mythical beings know that.
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    Quote Originally Posted by PetTastic View Post
    Quote Originally Posted by HexHammer View Post
    Even a non scientists would know that, just take an ordinary fridge magnet and attaract some iron, then that tiny magnet will counter the entire Eearth's gravity.

    Simple!
    Try that at a distance of more than a few inches or cm and gravity wins.
    Even the powerful pulling force of magnets used to lift cars in junk yards can't be even detected at the distance of a few yards.
    There is no detectable effect when flying a metal plane over the north pole.

    In space magnetic fields are purely a pushing force. Firing material away from the surface of stars at thousands of km/s.
    Because magnetism has curved lines and gravity may have straight radiant lines?
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    Quote Originally Posted by HexHammer View Post
    Quote Originally Posted by PetTastic View Post
    Quote Originally Posted by HexHammer View Post
    Even a non scientists would know that, just take an ordinary fridge magnet and attaract some iron, then that tiny magnet will counter the entire Eearth's gravity.

    Simple!
    Try that at a distance of more than a few inches or cm and gravity wins.
    Even the powerful pulling force of magnets used to lift cars in junk yards can't be even detected at the distance of a few yards.
    There is no detectable effect when flying a metal plane over the north pole.

    In space magnetic fields are purely a pushing force. Firing material away from the surface of stars at thousands of km/s.
    Because magnetism has curved lines and gravity may have straight radiant lines?
    If magnetic fields have any significant effect on solid objects in space why have all the iron asteroids not been pulled out of the asteroid belt leaving the rocky ones behind?
    I suggest you read up on magnetism on Wikipedia.
    I believe in nothing, but trust gravity to hold me down and the electromagnetic force to stop me falling through
    Physics is the search for the best model not the truth, as only mythical beings know that.
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    Quote Originally Posted by HexHammer View Post
    Even a non scientists would know that, just take an ordinary fridge magnet and attaract some iron, then that tiny magnet will counter the entire Eearth's gravity.
    Ah, so you are not basing your understanding of the universe on science? Got it.

    By that "logic" ... even a non-scientist knows that if you have a weight on the end of a rope, you can swing it around so it orbits your body. Therefore there must be a rope between the earth and the moon.
    ei incumbit probatio qui dicit, non qui negat
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    Quote Originally Posted by PetTastic View Post
    If magnetic fields have any significant effect on solid objects in space why have all the iron asteroids not been pulled out of the asteroid belt leaving the rocky ones behind?
    I suggest you read up on magnetism on Wikipedia.
    Probaly due to the Meissner Effect and probaly others too.
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    Quote Originally Posted by Strange View Post
    Ah, so you are not basing your understanding of the universe on science? Got it.

    By that "logic" ... even a non-scientist knows that if you have a weight on the end of a rope, you can swing it around so it orbits your body. Therefore there must be a rope between the earth and the moon.
    Now you are jumping to conclusions, it's words from a professor, nor do I see any faults in what I have said previously.
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    Quote Originally Posted by HexHammer View Post
    Now you are jumping to conclusions, it's words from a professor, nor do I see any faults in what I have said previously.
    The objective measurements and tested theories of science have determined that, on large scales, the dominant force in the universe is gravity. saying "ooh look, fridge magnet" doesn't really do much to challenge that.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by HexHammer View Post
    Now you are jumping to conclusions, it's words from a professor, nor do I see any faults in what I have said previously.
    The objective measurements and tested theories of science have determined that, on large scales, the dominant force in the universe is gravity. saying "ooh look, fridge magnet" doesn't really do much to challenge that.
    Oh wait what? That's why we'r looking for "Dark Matter", no that is just canceld by you.
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    Quote Originally Posted by HexHammer View Post
    Oh wait what? That's why we'r looking for "Dark Matter", no that is just canceld by you.
    Well, we are looking for [an explanation of] dark matter based on observation and measurement (you know, that "science" stuff).

    But I don't quite see the logic of your statement. Are you suggesting that the effects attributed to dark matter are in fact caused by some form of "dark magnetism"; i.e. there are powerful magnetic fields that are undetectable but strong enough to change the orbits of galaxies and cause gravitational lensing?
    ei incumbit probatio qui dicit, non qui negat
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by HexHammer View Post
    Oh wait what? That's why we'r looking for "Dark Matter", no that is just canceld by you.
    Well, we are looking for [an explanation of] dark matter based on observation and measurement (you know, that "science" stuff).

    But I don't quite see the logic of your statement. Are you suggesting that the effects attributed to dark matter are in fact caused by some form of "dark magnetism"; i.e. there are powerful magnetic fields that are undetectable but strong enough to change the orbits of galaxies and cause gravitational lensing?
    We have theorized "Dark Matter" because our current understanding of gravity and galaxies doesn't suffice. Our galaxy models disperse because there isn't enough gravity to keep it together.

    It puzzles and amazes me how you can jump to such farfeched conclusion that magnetism can alter the orbit of a galaxy and cause gravitational lensing, which I havn't talked about at all.

    Lensing can be cause by plasma, or by "cold weather effects" (can't remember the correct term) that sailors will experience by the poles distorting the apperance of their surroundings, a famous example was a nearby ship responding to Titanic's SOS call, was when the aiding ship looked at Titanic they would observe a ship that didn't look like Titanic at all, so they disregarded the SOS. This optical weather effect was little known at that time, and the captain of the aiding ship was trialed and found guilty of not aiding Titanic.

    I'm tired of your relentless trolling, and will just put you on ignore.
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    Quote Originally Posted by HexHammer View Post
    We have theorized "Dark Matter" because our current understanding of gravity and galaxies doesn't suffice.
    Well, one possible explanation is a modification of our understanding of the way gravity behaves.

    Our galaxy models disperse because there isn't enough gravity to keep it together.
    I'm not sure what you mean by that. It is not something I am aware of. Do you have any more information?

    It puzzles and amazes me how you can jump to such farfeched conclusion that magnetism can alter the orbit of a galaxy and cause gravitational lensing, which I havn't talked about at all.
    Well, you did say that the importance of magnetism and magnetars had been ignored. and then you brought up dark matter. Naturally, I assumed you were making a connection.

    Lensing can be cause by plasma, or by "cold weather effects" (can't remember the correct term) that sailors will experience by the poles distorting the apperance of their surroundings, a famous example was a nearby ship responding to Titanic's SOS call, was when the aiding ship looked at Titanic they would observe a ship that didn't look like Titanic at all, so they disregarded the SOS. This optical weather effect was little known at that time, and the captain of the aiding ship was trialed and found guilty of not aiding Titanic.
    Plasma, we would detect (it wouldn't be "dark"). Cold weather effects in space? Hmm...

    I'm tired of your relentless trolling, and will just put you on ignore.
    Well, if you think pointing out that uninformed speculation isn't as useful as a scientific approach is "trolling", then maybe you are better shutting yourself off in your cosy world and refusing to learn. Good luck.
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    HexHammer,

    .....Our galaxy models disperse because there isn't enough gravity to keep it together.
    I surmise from this that you are making reference to the MOND gravity model whereby most interpret it as gravity being stronger since the interpretation is that the force of gravity dissipates in the disk at a rate of 1/R instead of 1/R2 as in Newtonian gravity? If this was your meaning then you might consider that this is only one perspective of the differences between the formulas. The actual mechanics of gravity could instead be quite different as suggested by Strange, his quote below.

    ....one possible explanation is a modification of our understanding of the way gravity behaves.
    In Newtonian gravity almost all the mass being considered is at the center of the solar system within the sun, so we consider the primary force of gravity originating from the center of the solar system, in both logic and formulation. The same assumption is made with the MOND formulation concerning the source of gravity being the center of the galaxy. But in the disc of a galaxy there could be more matter on the outside of our location as there is on the inside. This is what is assumed with the dark matter hypothesis -- that most matter lies outside our orbit. We also assume that gravity is either a pulling force as in Newtonian gravity, or in GR that it is an inward movement of a body following the path of warped space surrounding matter. If none of these perspectives are correct concerning the force of gravity, then the mechanics of gravity could work quite differently than our current understanding of it.

    When Newton was asked why matter possesses the gravitational force, Newton replied that he did not propose hypothesis. When Einstein was asked why matter warps space he gave a similar answer. Students and scientists have been taught that the "why" questions belong in the domain of philosophy or religion. It could be that all of our theories, understandings, and related formulations in physics that cannot correctly answer the major "why" questions, may be incomplete or wrong, respectively resulting in their eventual incorporation or replacement.
    Last edited by forrest noble; April 26th, 2012 at 02:23 PM.
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    Dark matter and dark energy are reckoned to make up 80 % of matter in the universe because though we cannot detect it we can see the gravitational effects.


    First, no one can doubt the comparative strength of magnetic fields as presented in the table below. Gravity strength:1; electromagnetic strength 1,000,000,000,000,000,000,000,000,000,000,000,000. I think gravity is “slightly” outnumbered.

    Second, the range is infinite for both forces.

    Third, the interaction of objects is equivalent in the force equations for gravity and magnetism the only difference being that magnetism repels as well as attracts (charge dependant).




    Interaction

    Current theory

    Mediators

    Relative strength[1]

    Long-distance behavior

    Range (m)
    Strong Quantum chromodynamics
    (QCD)
    gluons 1038 (see discussion below) 10−15
    Electromagnetic Quantum electrodynamics
    (QED)
    photons 1036
    Weak Electroweak Theory W and Z bosons 1025 10−18
    Gravitation General Relativity
    (GR)
    gravitons (hypothetical) 1



    Source: http://en.wikipedia.org/wiki/Fundamental_interaction

    To ignore a force so massive in cosmic calculations is just wrong.

    So, at a distance and considering the forces are equivalent in range and behavior, how can you tell them apart?

    Where are the gravimetriscopes or electromagnetiscopes that allow us to view the forces we are theorizing through mathematical equations? Not invented as of yet?

    The effect of electromagnetic forces on charged particles is fact and not theory. We use this principle everyday. Where is the equivalent in gravity?

    Every chemical reaction is electrical in nature; every nerve pulse from your fingers to the retina in your eye is due to electricity and electron flow. Every cell phone, every computer, all matter is electric. The forces that bind atoms together are electric. It is only on the cosmic scale we neglect this force.

    When was the last time a gravimetric wave damaged anything on earth? Is there any historical basis for believing this has ever happened? Can you see the effects of gravity except as a weak force holding objects on the surface of the earth?

    Compare this to the effects of a coronal mass ejection of charged particles (plasma). Search the term Carrington effect.

    I am not discounting the current theories as worthless as they have been able to accurately describe many events, adding electro-magnetic effects would help explain many things. Maybe even dark matter.
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    jetstove,

    What is stronger, the force of magnetism or the force of gravity (rhetorical)? There is more than one way to look at it. For instance if you replaced our moon with a Magnetar (magnetic stellar remnant) of .1 solar mass, maybe within a few days the magnetic strips on your drivers license and credit cards would be wiped out. But maybe in the same period of time but no more than a few weeks, we would move toward the Magnetar via gravity and be crushed and absorbed by it. What is stronger magnetism or gravity (rhetorical) ? It depends upon your perspective

    Current theory has it that gravity is not a force, proposed by Einstein as caused by the warping of space -- whether right or wrong. On the chart that you posted, it is incorrect to have GR on the same line as hypothetical gravitons since they are proposals from two different theories. Gravitons are a hypothetical proposal of quantum field theory.

    Plasma Cosmology asserts that magnetic influences in a galaxy via plasma currents (a flow of charged particles likened to an electrical current) could influence the original location of stars within a galaxy or somehow effect orbital mechanics of the galaxy as long ago proposed by Hannes Alfven. Very few if any mainstream scientists would agree in the possibility that magnetic/ electric influences could control the motions of an entire galaxy after it was already formed. Plasma Cosmology proponents believe such forces affected the original form of the galaxy but believe these forces become a minor player as galaxies age.

    On the other hand, some "Electric Universe (EU)" proponents, another electromagnetic cosmology, do believe such electromagnetic forces within galaxies have more influence on stellar locations and their orbital velocities than gravity does. Such proposals, however, lack in logical mechanisms based upon observation, and equations with numerical predictive capabilities. Functioning equations are considered the hallmark of a good theory.
    Last edited by forrest noble; April 27th, 2012 at 11:45 AM.
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    Quote Originally Posted by jetstove View Post
    First, no one can doubt the comparative strength of magnetic fields as presented in the table below. Gravity strength:1; electromagnetic strength 1,000,000,000,000,000,000,000,000,000,000,000,000. I think gravity is “slightly” outnumbered.
    I doubt it. Did you miss the bit where it says "gravitons (hypothetical)"? Without gravitons, the coupling constant has no meaning.

    I also doubt its relevance. Try and pick up a feather with a magnet. You can't. And yet it will fall to Earth just as fast as a ton of lead. (Which you also can't pick up with a magnet.)

    Second, the range is infinite for both forces.
    So what. Magnetic force falls of with an inverse cube law; whereas gravity falls of with a square law. Bazinga.

    Third, the interaction of objects is equivalent in the force equations for gravity and magnetism the only difference being that magnetism repels as well as attracts (charge dependant).
    And the fact that gravity affects all forms of mass and energy and magnetism ... doesn't.

    To ignore a force so massive in cosmic calculations is just wrong.
    (a) It isn't massive.
    (b) It hasn't been ignored (why would it be). It has been taken into account and found to be insignificant. Unless you can cite some scientific research that shows otherwise? (And I do mean scientific research - nothing from "electric universe", "plasma cosmology", or similar crackpot websites please).

    Where are the gravimetriscopes or electromagnetiscopes that allow us to view the forces we are theorizing through mathematical equations? Not invented as of yet?

    The effect of electromagnetic forces on charged particles is fact and not theory. We use this principle everyday. Where is the equivalent in gravity?
    Are you trying to say that we cannot measure gravity? There is a very sophisticated piece of equipment you may have in your own home that will allow you to do this: w e i g h i n g s c a l e s.

    Every chemical reaction is electrical in nature; every nerve pulse from your fingers to the retina in your eye is due to electricity and electron flow. Every cell phone, every computer, all matter is electric. The forces that bind atoms together are electric.
    Relevance? Or is your straw man that people deny the existence of electricity?

    It is only on the cosmic scale we neglect this force.
    It isn't neglected.

    adding electro-magnetic effects would help explain many things. Maybe even dark matter.
    Do you think cosmologists and physicists are so stupid that might not think of this? Do you think there is some sort of conspiracy to hide the truth?

    Perhaps you could show the experimental data and the calculations that support this idea?
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by jetstove View Post
    First, no one can doubt the comparative strength of magnetic fields as presented in the table below. Gravity strength:1; electromagnetic strength 1,000,000,000,000,000,000,000,000,000,000,000,000. I think gravity is “slightly” outnumbered.
    I doubt it. Did you miss the bit where it says "gravitons (hypothetical)"? Without gravitons, the coupling constant has no meaning.
    Hypotheticals are situations, statements or questions about something imaginary rather than something real. Hypotheticals - Wikipedia, the free encyclopedia

    Quote Originally Posted by Strange View Post
    I also doubt its relevance. Try and pick up a feather with a magnet. You can't. And yet it will fall to Earth just as fast as a ton of lead. (Which you also can't pick up with a magnet.)
    I can pick up a feather with a comb I have used on my hair; against the force of gravity. I can place lead and gold leaf in a leyden jar and watch them separate through the addition of electricity.

    Second, the range is infinite for both forces.
    Quote Originally Posted by Strange View Post
    So what. Magnetic force falls of with an inverse cube law; whereas gravity falls of with a square law. Bazinga.

    Coulomb's law explains the scale between two electric charges. The scale of electrostatic force follows the function below.


    source Coulomb's law - Simple English Wikipedia, the free encyclopedia







    source: Newton's law of universal gravitation - Wikipedia, the free encyclopedia


    Third, the interaction of objects is equivalent in the force equations for gravity and magnetism the only difference being that magnetism repels as well as attracts (charge dependant).
    Quote Originally Posted by Strange View Post
    And the fact that gravity affects all forms of mass and energy and magnetism ... doesn't.

    Sorry electromagnetism please. All substances are capable of holding or carrying a charge. Keep your fingers out of light sockets please.

    To ignore a force so massive in cosmic calculations is just wrong.
    Quote Originally Posted by Strange View Post
    (a) It isn't massive.
    (b) It hasn't been ignored (why would it be). It has been taken into account and found to be insignificant. Unless you can cite some scientific research that shows otherwise? (And I do mean scientific research - nothing from "electric universe", "plasma cosmology", or similar crackpot websites please).

    (a) 10^ 36 is comparatively massive. Count the zeros
    (b) I didn't realize that Einstein had used electromagnetics in his theory of general relativity Please show me the equations. I need a citation.

    Where are the gravimetriscopes or electromagnetiscopes that allow us to view the forces we are theorizing through mathematical equations? Not invented as of yet?


    The effect of electromagnetic forces on charged particles is fact and not theory. We use this principle everyday. Where is the equivalent in gravity?[/QUOTE]

    Quote Originally Posted by Strange View Post
    Are you trying to say that we cannot measure gravity? There is a very sophisticated piece of equipment you may have in your own home that will allow you to do this: w e i g h i n g s c a l e s.
    Gravimetric devices are used all the time on the earth. They are used for geological research (gravitational anomalies) and survey. Where are the ones that are used to measure the gravitational forces from other stars and galaxys? You know, like radio telescopes?

    Every chemical reaction is electrical in nature; every nerve pulse from your fingers to the retina in your eye is due to electricity and electron flow. Every cell phone, every computer, all matter is electric. The forces that bind atoms together are electric.
    Quote Originally Posted by Strange View Post
    Relevance? Or is your straw man that people deny the existence of electricity?
    Electromagnetism (you mean) and it's effects on a cosmic scale? Yes.


    adding electro-magnetic effects would help explain many things. Maybe even dark matter.
    Quote Originally Posted by Strange View Post
    Do you think cosmologists and physicists are so stupid that might not think of this? Do you think there is some sort of conspiracy to hide the truth?

    Perhaps you could show the experimental data and the calculations that support this idea?
    Do some work yourself and hunt down your own links showing that electromagnetism is insignificant.

    As for conspiracies? Read post 18 at this link and the embedded links.

    Vigorous Weeding needed !?

    If you are reading this exchange please go back and read my initial post as it has not been entirely quoted.

    By the way, Strange, Is your avatar a fractal, a cauliflower, or magnetic flux lines displayed in a ferro-magnetic liquid? I really can't tell.
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    Could it be that we have actually mistaken white holes for supernovas and these white holes are providing the excess gravity previously theoretically attributed to dark matter?
    “The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.”

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    Quote Originally Posted by Chrisgorlitz View Post
    Could it be that we have actually mistaken white holes for supernovas and these white holes are providing the excess gravity previously theoretically attributed to dark matter?
    Supernovas represent a brief instant in time and were the basis for the Dark Energy hypothesis and are unrelated to gravitational influences. Some think white holes can be long lasting like black holes. For the possiblility of short duration white holes, as you said some believe in the possibility. The dark matter hypotheses, on the other hand, originated from the fact that spiral galaxies' orbital velocities concerning their stars, do not follow Newtonian or Einsteinian formulations based upon what was observed. For this reason extra mass was needed for a possible explanation, hence the dark matter hypothesis.
    Last edited by forrest noble; April 28th, 2012 at 04:26 PM.
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    I think you guys are ignoring the results of the survey.

    It looked at the movement of 400 hundred stars and found only normal gravity acting on normal matter.

    Inside the test volume, it found no mysterious forces that needed explaining.

    Inside this volume it found nothing holding the galaxy together

    If this result is not an error and is repeated by future surveys then the galaxy must be flying apart.

    If the survey had found the effects of dark matter, then you could claim, "No it is not dark matter, it is ........"
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    PetTastic,

    ....If this result is not an error and is repeated by future surveys then the galaxy must be flying apart. If the survey had found the effects of dark matter, then.....
    Our galaxy might be expanding but not flying apart. I think their findings will be confirmed and wouldn't have believed it if they would have claimed they found dark matter. There have been many previous claims concerning finding dark matter. Maybe a better idea might be the one Strange mentioned in his posting #55

    ....one possible explanation is a modification of our understanding of the way gravity behaves.
    Last edited by forrest noble; April 27th, 2012 at 11:10 AM.
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    Quote Originally Posted by forrest noble View Post
    PetTastic,

    ....If this result is not an error and is repeated by future surveys then the galaxy must be flying apart. If the survey had found the effects of dark matter, then.....
    Our galaxy might be expanding but not flying apart. I think their findings will be confirmed and wouldn't have believed it if they would have claimed they found dark matter. There have be many such previous claims. Maybe a better idea might be the one Strange mentioned in his posting #55

    ....one possible explanation is a modification of our understanding of the way gravity behaves.
    Ok flying apart was an exaggeration, more like spiraling out at about 15 degrees from the tangent, 30 to 60 km/s sec radial.

    The survey goes out 13k lightyears away from the disk, but does not seem to find anything keeping the disk as thin as it is.
    I think this causes big problems with theories on how galaxies form.

    Elsewhere I saw the suggestion that cold dark matter absorbed the energy of galaxy collisions to become some form of hot dark matter, that would be harder to detect at the small scale.
    This preserves explanations for WMAP data and the formation of the first galaxies.
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    This news from February says that dark matter existed primarily outside our galaxy, it skirt our galaxy, and is detected by gravitational lensing: Missing dark matter located: Intergalactic space is filled with dark matter .
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    BBC-What on Earth Is Wrong with Gravity BL 02 - YouTube 3:10 moon is about 10m out of place
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    Quote Originally Posted by HexHammer View Post

    Yes, old Newtonian gravity is only an approximation, but general relativity works!
    I believe in nothing, but trust gravity to hold me down and the electromagnetic force to stop me falling through
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    Quote Originally Posted by msafwan View Post
    This news from February says that dark matter existed primarily outside our galaxy, it skirt our galaxy, and is detected by gravitational lensing: Missing dark matter located: Intergalactic space is filled with dark matter .
    I only scanned the paper
    [1105.3005] Matter Distribution around Galaxies
    But, it looks like they are assuming dark matter insde the galaxy to calculate the amount outside?
    Their graphs have a very high mass density inside the galaxy.
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    PetTastic,

    Ok flying apart was an exaggeration, more like spiraling out at about 15 degrees from the tangent, 30 to 60 km/s sec radial.

    The survey goes out 13k lightyears away from the disk, but does not seem to find anything keeping the disk as thin as it is.
    I think this causes big problems with theories on how galaxies form.
    I also agree that some spiral galaxies may lose a certain portion of their outer stars by galactic expansion over billions of years. I think the survey conclusions not only "causes big problems with theories on how galaxies form," but also might be an indication of a total misunderstanding of gravity mechanics in all venues. Just because in some venues gravity formulations can make consistently accurate predictions does not mean that the verbal explanations of the theory are valid, or that it can make accurate predicts in all venues and circumstances.

    Elsewhere I saw the suggestion that cold dark matter absorbed the energy of galaxy collisions to become some form of hot dark matter, that would be harder to detect at the small scale.........
    Since we have not identified/ discovered CDM, it would still be a big leap if we found a heat signature which was thought to be related to galaxy collisions and then asserted that this was an indication/ evidence for CDM to start with.

    This preserves explanations for WMAP data and the formation of the first galaxies.
    Our understanding of galaxy creation may also be wrong if we do not understand the basis of gravity mechanics without dark matter.

    The non-existence of Cold Dark Matter i(CDM) would be a big problem for the standard model. The underpinnings of the entire theory is based upon the mathematics of GR and its related cosmological equations. Without GR and dark matter, I think there would be very little left to support the BB model and I would expect its gradual replacement if/ when theorists start considering other models of gravity and cosmology. Your quote from the Royal Astronomical Society below, I believe, is a prime example and harbinger of theoretical changes that may be expected in the not too distant future if such observations are consistently confirmed.

    “...Our model appears to rule out the presence of dark matter in the universe, threatening a central pillar of current cosmological theory. We see this as the beginning of a paradigm shift, one that will ultimately lead us to a new understanding of the universe we inhabit.”

    http://www.ras.org.uk/news-and-press...or-dark-matter
    Last edited by forrest noble; April 28th, 2012 at 07:11 AM.
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    Quote Originally Posted by forrest noble View Post
    Quote Originally Posted by Chrisgorlitz View Post
    Could it be that we have actually mistaken white holes for supernovas and these white holes are providing the excess gravity previously theoretically attributed to dark matter?
    Supernovas represent a brief instant in time and were the basis for the Dark Energy hypothesis and are unrelated to gravitational influences. White holes theoretically are long lasting like black holes. The dark matter hypotheses, on the other hand, originated from the fact that spiral galaxies' orbital velocities concerning their stars, do not follow Newtonian or Einsteinian formulations and extra mass was needed for a possible explanation, hence dark matter.
    Isn't it true that in 2006 what at the time was believed to be a supernova has since been speculated to be a mass ejection from whitehole lasting just over 3 minutes, also if this actually proves to be correct then there could be whiteholes opening and closing, throughout the galaxy, spewing in extra mass.
    “The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.”

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    No. What are you attempting to refer to? (White Holes do not exist)
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    Chrisgorlitz,

    ......Isn't it true that in 2006 what at the time was believed to be a supernova has since been speculated to be a mass ejection from whitehole lasting just over 3 minutes, also if this actually proves to be correct then there could be whiteholes opening and closing, throughout the galaxy, spewing in extra mass.
    White Hole Theory is considered to be one possibility of Einstein's field equations. Some famous theorists such as Hawking, Penrose and many others have speculated concerning the possibility of white holes. Most theorist's today, however, believe there has been no observational evidence to support the consideration of a white hole's existence.

    Similar to white hole theory, very massive ejections from galactic sized black holes, with or without the accompaniment of vast EM radiation, has been a proposal by Halton Arp for more than 40 years. His theories assert that this is the source of many or most Quasars. He has stated, however, that he thinks these theoretical ejections if they are someday considered to be coming from white holes (black holes temporarily ejecting copious light/matter) , are probably unrelated to the theoretical physics of Einstein's Field Equations.

    http://en.wikipedia.org/wiki/White_hole
    Last edited by forrest noble; May 21st, 2012 at 04:30 PM.
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    Quote Originally Posted by MeteorWayne View Post
    No. What are you attempting to refer to? (White Holes do not exist)
    I was refering to the GRB 060614 gamma burst, may not have got the duration entirely accurate, some sources state it was actually 102 seconds.
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    Quote Originally Posted by SpeedFreek View Post
    Quote Originally Posted by MeteorWayne View Post
    A thought from my head. The prevailing hypothesis is that the Milky Way is created by the merger of many smaller galaxies, in which the smaller galaxies normal matter is ripped apart and "eaten" or absorbed. There's very good evidence for this. That interaction ruled not only by gravity, but collisional interactions of the gas included in the galaxies.

    However, it would take much longer for the dark matter spheroids to smoothly merge, since there are no collisional effects to "quickly" remove the momentum from the dark matter. (See the Bullet Cluster). Therefore it would take much longer for that merger to take place, so one would expect DM to not be homogenous. While the overall effect might be that of a "perfect" sphere, on smaller scales it might be quite lumpy within a specific galaxy for tens of billions of years post merger.

    MW
    I would tend to agree with you that something like this could be closer to the heart of the problem.

    We have observational evidence of gravitational lensing, a prediction of general relativity. We see multiple and often distorted images of a background galaxy, around a gravitational source that lies (presumably) directly between us and that background galaxy.

    We also have observational evidence, from this gravitational lensing, that if general relativity is correct, there is more matter in clusters of galaxies than the matter we can see. So either general relativity is wrong, or there is more matter in those clusters of galaxies than we can see. Hence the need for "dark matter", whatever that term turns out to represent.

    We also have observational evidence in places like the Bullet Cluster and MACS J0025.4-1222, that these "extra" effects of gravitational lensing do not necessarily stay with the concentrations of matter when they collide - the dark matter is somewhat separated from the normal matter.

    If there is no dark matter, whatever it is, then an alternative theory of gravity is going to have to come up with a way to explain how gravitational lensing seems to show a gravitational effect that can apparently be separated from normal matter.
    There would seem to be a strong limit on how close a lump of dark matter could be to us, and not be detected.
    The survey was a 13K light year cone of about 15 degrees.
    On average one star in the survey would be about 4.5K lightyears closer to any double density lump of DM than another.

    One possibility is we have the distances between galaxies too small, and normal mass/gravity is bending light by only a small angle.
    Then maybe you can explain the extra matter in colliding clusters as conventional DM penetrating gas clouds, but gas colliding to form visible stars?
    Last edited by PetTastic; April 30th, 2012 at 06:10 AM. Reason: Fixed last line
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    This might be of interest: Researchers Bring Dark Matter Back
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    Quote Originally Posted by Strange View Post
    This might be of interest: Researchers Bring Dark Matter Back
    Interesting story, I just wonder what sort of containment you would even need to actually hold dark matter, I mean we don't even know if there is different types with differing masses.
    Or how it would react with nomal matter, is inert, reactive or explosive even? I would think the whole proposition of collecting it must be pretty risky at best.
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    Since Dark Matter (Whatever It Is) only interacts with regular matter through gravity, and then only weakly, there's really no way to contain it.
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    The Dark matter hypothesis is deeply entrenched in the BB model and is just now beginning to experience observational contradictions. If dark matter does not exist then GR would be wrong in both its gravitational and lensing equations and predictions since it cannot even come close to explaining many observations at the galactic scale without injectiing vast quantities of dark matter into the equations.

    Alternative gravitational models might explain motions in spiral galaxies without dark matter but fail at both larger and smaller scales. Unless all venues are explainable by another theory of gravity, the dark matter hypothesis will seemingly continue to be used to support General Relativity and the BB model, even in the face of mounting observational contradictions.
    Last edited by forrest noble; May 21st, 2012 at 05:32 PM.
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    I guess you didn't read the article in post #76...
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    Quote Originally Posted by MeteorWayne View Post
    I guess you didn't read the article in post #76...
    I sure did. That was the reason for my posting -- the point being that they cannot readily accept fault with the dark matter hypothesis since it would leave too big of a hole in present theory.
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    But it didn't agree with your notion, so it must be the one that's wrong? It contridicted the earlier paper.

    Which one is right? I don't know, they will duke it out on the field of science, so we shall see. That's how it's done.
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    .....they will duke it out on the field of science, so we shall see. That's how it's done.
    Yep, that's how it's done And may the better model win
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    Quote Originally Posted by forrest noble View Post
    the point being that they cannot readily accept fault with the dark matter hypothesis since it would leave too big of a hole in present theory.
    That is the silliest thing I have read in a long time.

    They think they found a flaw in the previous paper so they reported that. That is what responsible scientists do. That is why science works. And it works both ways: people point out errors in papers which explain dark matter as well as those which argue it might not be there.

    Or maybe you think they didn't find a fault in the previous paper, they are just pretending because they cannot accept there might be something wrong with their pet theory?

    The good news is, it gives us more data for determining how much dark matter there is.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by forrest noble View Post
    the point being that they cannot readily accept fault with the dark matter hypothesis since it would leave too big of a hole in present theory.
    That is the silliest thing I have read in a long time.

    They think they found a flaw in the previous paper so they reported that. That is what responsible scientists do. That is why science works. And it works both ways: people point out errors in papers which explain dark matter as well as those which argue it might not be there.

    Or maybe you think they didn't find a fault in the previous paper, they are just pretending because they cannot accept there might be something wrong with their pet theory?

    The good news is, it gives us more data for determining how much dark matter there is.

    In such matters you may be a wee bit naive. This study by a team of astronomers and scientists, was one of the most damaging so far to the dark matter hypothesis. Two researchers reviewing their data and came to a different conclusion.

    As I pointed out, the dark matter hypothesis is now an essential part of the standard model. Without it the model seemingly will not survive. Therefore there is great motivation to find errors in anything that might contradict GR or the BB model. There is nothing wrong with two researchers criticizing the original study and coming to a different conclusion; that is science. If this did not happen I think it would have been more of a surprise. But the original study was not the most damaging study to the dark matter hypothesis.

    The study below I believe was the most damaging concerning Milky Way companions and contradictions of the dark matter hypothesis.

    Do the Milky Way

    Their conclusion seems astounding to me considering how conservative the Royal Astronomical Society usually is.

    This was their concluding statement:

    "Our model appears to rule out the presence of dark matter in galaxies, threatening a central pillar of current cosmological theory. We see this as the beginning of a paradigm shift, one that will ultimately lead us to a new understanding of the universe we inhabit.”
    The key words here I think are "a new understanding," with the meaning that replacement theories may be needed.

    Of course all should expect that this study too will be analyzed with a fine-toothed comb, and some of those doing such studies will also come to different conclusions. This is the natural process of science, but to a greater extent when a standard model is under attack.

    I am not against the idea of dark matter, instead I think it exists in the form of a quantum-length particulate aether, but not in the form of matter.
    Last edited by forrest noble; March 28th, 2013 at 08:44 PM.
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    could dark matter be remnants of fusioned particles with mass being its only property?
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    Quote Originally Posted by curious mind View Post
    could dark matter be remnants of fusioned particles with mass being its only property?
    Electrons are theorized to be point particles so I do not see why dark matter could not likewise be conceived to be a point particle, with mass being its primary property. Since they still do not know what it really is, or even if it really exists as matter, leaves many theoretical doors still wide open.
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    well, if a streaming universe is wrong, it has to be a something with mass not carrying any information but only mass, recognized by/through effects that matter with mass holding information does.
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    Quote Originally Posted by curious mind View Post
    could dark matter be remnants of fusioned particles with mass being its only property?
    Not sure what you mean by "fusioned particles"?

    It can't, as far as we know, be any "normal" particles because they nearly all interact via the electromagnetic force and (in some cases) other forces. Which dark matter appears not to. The only particle we know that seems to have this property is the neutrino, but they appear to be too light and too fast moving to explain dark matter.
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    Hopefully, we will know a little more on the subject in the next few hours.
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    On the outside, most of the inside is filled with caramel.
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    Quote Originally Posted by shlunka View Post
    On the outside, most of the inside is filled with caramel.
    as funny as this sounds, that's what i'm thinking. inside the galaxies the white (visible) matter formed. it's like active and passive matter.
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