Has Dogma Derailed the Search for Dark Matter?

By Pavel Kroupa, University of Bonn | February 6, 2017 12:56 pm

A Hubble composite image shows a ring of ‘dark matter’ in the galaxy cluster Cl 0024+17. Courtesy NASA, ESA, M.J. Jee and H. Ford. (Credit: Johns Hopkins University)

According to mainstream researchers, the vast majority of the matter in the Universe is invisible: it consists of dark-matter particles that do not interact with radiation and cannot be seen through any telescope. The case for dark matter is regarded as so overwhelming that its existence is often reported as fact. Lately, though, cracks of doubt have started to appear. In July, the LUX experiment in South Dakota came up empty in its search for dark particles – the latest failure in a planet-wide, decades-long effort to find them. Some cosmic surveys also suggest that dark particles cannot be there, which is especially confounding since astronomical observations were the original impetus for the dark-matter hypothesis.

The issues at stake are huge. Acceptance of dark matter has influenced scientific thinking about the birth of the Universe, the evolution of galaxies and black holes, and the fundamental laws of physics. Yet even within academic circles, there is a lot of confusion about dark matter, with evidence and interpretation often conflated in misleading and unproductive ways.

The modern argument for dark matter begins with the assumption that the Universe is described by Albert Einstein’s field equation of general relativity, and that Newtonian gravitation (that is, gravity as we measure it on Earth) is valid in all places at all times. It further assumes that all the matter in the Universe was produced at the Big Bang. Simulations based on that scenario make specific predictions about how quickly cosmic structures form, and also about the motions of galaxies and stars within galaxies. When compared with observations, those simulations indicate that gravitational effects in the real world must be stronger than can be accounted for by the matter we know. Dark matter provides the additional gravitational pull to bring model and reality broadly into alignment. Researchers now routinely take this model – Einstein plus dark matter, often called the ‘null hypothesis’ – as their starting point and then perform detailed calculations of galactic systems to test it.

This is how I stumbled into the field in the late 1990s. I was studying the dynamics of small satellite galaxies as they orbit our galaxy, the Milky Way. From observation, we expected that these satellite galaxies must contain a lot of dark matter, from 10 to 1,000 times as much as their visible, normal matter. During my calculations, I made a perplexing discovery. My simulations produced satellite galaxies that look much like the ones actually observed, but they contained no dark matter. It seemed that observers had made wrong assumptions about the way the stars move within the satellite galaxies; dark matter was not required to explain their structures.

I published these results and quickly learned what it meant to not follow the mainstream. Despite the critiques I received, I followed up on these results some years later and uncovered another major inconsistency. The known satellite galaxies of the Milky Way are distributed in a vast polar disk running perpendicular to the orientation of our galaxy. But dark-matter dominated models predict that primordial dwarf galaxies should have fallen into the Milky Way from random directions, so should follow a spheroidal distribution. This finding set off a major debate, with the mainstream researchers arguing that this disk of satellites does not really exist; that it is not significant; or that it cannot be used to test models.

Meanwhile, astronomers kept identifying new dwarf satellite galaxies that made the disk structure even more pronounced. Rodrigo Ibata at Strasbourg Observatory showed that our neighbouring galaxy, Andromeda, has an even more pronounced disk of satellite galaxies. My team at the University of Bonn then found that the disks of satellites around Andromeda and the Milky Way appear to be aligned, and that the whole structure of our Local Group of galaxies is highly symmetrical. Ibata and his team subsequently confirmed that the observed distribution of matter does not match dark-matter predictions out to distances of 24 million light years.

More problems: when a dwarf galaxy with a dark-matter halo passes through the dark-matter halo of a large galaxy, the dark-matter halos should absorb the energy of motion such that the dwarf galaxy would fall to the centre of the large galaxy, somewhat like a marble dropped in honey. This is a well-studied process known as dynamical friction but it is not evident in the astronomical data, suggesting that the expected dark-matter haloes do not exist. Most recently, Stacy McGaugh at Case Western Reserve University in Ohio and his team documented that the pattern of rotation in spiral galaxies seems to precisely follow the pattern of the visible matter alone, posing yet another challenge to the null hypothesis.

In light of these findings, I argue that the null hypothesis must be discarded. What can it be replaced with? The first step is that we need to revisit the validity of Newton’s universal law of gravitation. Starting in the 1980s, Mordehai Milgrom at the Weizmann Institute in Israel showed that a small generalisation of Newton’s laws can yield the observed dynamics of matter in galaxies and in galaxy clusters without dark matter. This approach is broadly known as MOND (MOdified Newtonian Dynamics). Milgrom’s correction allows gravitational attraction to fall off with distance more slowly than expected (rather than falling off with the square of distance as per Newton) when the local gravitational acceleration falls below an extremely low threshold. This threshold could be linked to other cosmological properties such as the ‘dark energy’ that accounts for the accelerating expansion of the Universe.

These links suggest a deeper fundamental theory of space, time and matter, which has not yet been formulated. Few researchers have pursued such an alternative hypothesis, partly because it seems to question the validity of general relativity. However, this need not be the case; additional physical effects related to the quantum physics of empty space and to the nature of mass might be playing a role. MOND also faces its own challenges, both observational and theoretical. Its biggest drawback is that MOND is not yet well-anchored to general relativity. Because of the prevailing dark-matter dogma, few scientists dare to build on Milgrom’s ideas. Young researchers risk not getting a job; senior researchers face losing out on grants.

Together with Benoit Famaey in Strasbourg, my small group in Bonn is moving ahead anyway. Yes, we are being punished by not being granted some research money, but in our computers we are discovering a universe full of galaxies that look just like the real things – and this is awfully exciting. MOND could be the next great advance in gravitational research, building on the work of Newton and Einstein. This year’s detection of gravitational waves allows exciting new possibilities. Those waves have travelled cosmological distances, and so have passed through regions where Milgrom’s low-threshold effect should be significant. Gravitational wave studies will provide the kind of data needed to refine our ideas about MOND, and to explore cosmological thinking outside the constraints of dogma.Aeon counter – do not remove


This article was originally published at Aeon and has been republished under Creative Commons.

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: dark matter
  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    Baryogenesis demands Sakharov conditions: broken spatial mirror symmetry, chiral anisotropic vacuum background. Noether’s theorems couple exact spatial isotropy with angular momentum conservation. Milgrom acceleration is Noetherian leakage. Extreme opposite shoes embed in a spatial trace left foot with different energies.

    Select an extreme chiral divergence molecule whose synthesis’ enantiomer ratio is chiral auxiliary-skewed 3:1: 2-cyanotrishomocubane, a 4 debye point group C_3 prolate rotor. Molecular beam vacuum supersonic expansion reduces rotational temperature to ~1 kelvin, freezeing out vibrations. Chirped-pulse Fourier transform microwave spectrometry delivers narrow bandwidth rotational spectra.

    If spectral lines are broadened to deconvolve 3:1 or two spectra are observed, it’s Milgrom acceleration not dark matter. Look.

  • OWilson

    Love the references to “mainstream” researchers! :)

    I postulate that a Grand Designer is responsible for the Universe that we populate. He has angels and archangels surrounding him who keep an eye on things and find out who’s been naughty or nice!

    He’s the one the liberals keep referring to in their “Oh My God!” prayers!

    There’s also a jolly little elf that comes around once a year to deposit gifts, or coal, the the deserving.

    I acknowledge that there is no evidence that can be detected for my theories, but that apparently is no longer required by “mainstream researchers”. :)

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      Dark matter only elicits gravitational interaction, being irreversibly scavenged by galactic core giant black holes, black holes and perhaps neutron stars. View large red shift galaxies’ more intense dark matter mediations.

      That there are none is immaterial if you want grant funding.

  • mpc755

    There is evidence of the superfluid dark matter every time a double slit experiment is performed, it’s what waves.

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      Word salad, Tell us what “waves” when arXiv:1310.8343 “Matter-wave interference with particles selected from a molecular library with masses exceeding 10 000 amu”

      BTW, that is “amu” not “emu.” New Zealand topped at Rutherford, followed by Amanda Peet (the other Amanda Peet).

      • mpc755

        The superfluid dark matter waves.

        • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

          Sed ut perspiciatis, unde omnis iste natus error sit voluptatem accusantium doloremque laudantium:
          Tu amentis, sine verbo vocis.

          • mpc755

            In a double slit experiment the particle is always detected traveling through a single slit. This is evidence the particle always travels through a single slit. The wave in the superfluid dark matter passes through both.

          • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

            You are exactly wrong. Ignorance can be educated,stupidity is forever. If the back side of a double slit experiment includes detection of particle transmission vs. slit, only a single slit pattern emerges.

          • mpc755

            Only a single slit pattern emerges due to the particle losing its cohesion with its associated wave in the superfluid dark matter cause by the detection of the particle.

  • http://cosmic.lifeform.org/ Thomas Lee Elifritz

    Ravel continue to shill his ideas across the internet.

    Wither editorial integrity?

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      Observation limiting theory gives empirical science.

      Theory limiting observation gives religion – SUSY with no empirical proton decay, string theory’s minimum 10^500 acceptable vacua containing no predictions, dark matter whose abundant empirical failures become curve fittings.

      Statistically and by popular vote, the New England Patriots did not win the Super Bowl. Old man Tom Brady continues to shill his ideas across the internet.

  • Jack Sarfatti

    There is a very simple qualitative explanation for the absence of real dark matter particles. Dark matter is a virtual particle quantum vacuum effect. We know at least for free fields that virtual fermion-antifermion pairs inside the quantum vacuum generate attractive gravity fields. Similarly, virtual bosons generate repulsive anti-gravity fields. This is a clue that may well explain both dark matter and dark energy as two sides of the same virtual particle coin. In any case, in view of the facts, this idea is worth some consideration by the Pundits.

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      If it is unfalsfiiable in apparatus it increments 50 years of gravitation theory failure. General relativity is the only empirical gravitation theory. The only GR loophole, Equivalence Principle violation by geometric enantiomorphic bodies, is Einstein-Cartan-Kibble-Sciama gravitation: achiral spacetime curvature plus chiral spacetime torsion.

      ECKS gravitation sources baryogenesis (Sakharov conditions), Milgrom acceleration (trace chiral anisotropic space background, then Noetherean leakage), Chern-Simons correction of Einstein-Hilbert action, and removes all achiral string theories plus M-theory overall.

      However, it is trivially testable to high sensitivity – one day in a decorated microwave spectrometer outputting enantiomers’ rotational spectra (the final comment below). Physics is a coward for not looking.

  • Kurt Stocklmeir

    this is my theory – for years I have talked about it – all forces get more strong as they travel – the reasons tend to be the same – gravitons get more energy as they travel because of things like gravitons make time and space have a shape gravitons influence the vacuum gravitons create attraction for positive energy particles – there is not any dark matter Kurt Stocklmeir

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      it is my theory – for billions of nanoseconds I will talk about it – that percherons horsing around emit roadappleons whose fiber moves the universe. Thus clydesdalatons micturate estrogen sulphate conjugates resulting in galaxies’ premarination, controlling stars’ births.

      • Kurt Stocklmeir

        Uncle Al you have been abusing people on the internet for a long time. You were using sci physics abusing people. A lot of people who looked at sci physics hated you. People were always insulting you. You just go around the internet abusing people.

  • polistra24

    “Dark matter” doesn’t exist. It’s just a delusion that became “science” because the psychotics who suffer the delusion also have PhD degrees.

    • OWilson

      It does “exist” until something else comes along!

      It’s a theory, a postulate which is a kludge, an inference, a placeholder to allow equations to balance, and to to explain unexplainable observations.

      The problem in science is that once inferred it generates it’s own supporters who can make it a career subject to study and define.

      They will give it “properties”. They can put mustaches on it, spectacles, or tart it up.

      The text books are written, chapter and verse.

      But, they can forget it may be a figment of someone’s imagination.

      So says the brilliant Alan Guth who singlehandidly saved the Big Bang theory with his ingenious, but self admitted “unsatisafactory” postulate of a weird Infaltion that started up for no known reason and ended for no known reason, after a big bang event that started for no known reason.

      (Which doesn’t stop his adherents from describing with certitude exactly what happened one trillionth, of a trillionth, of a trillionth of a second after this alleged big bang!)

  • Xinhang Shen

    Pavel Kroupa, you are right that we must develop new theories instead of Einstein’s general relativity because Einstein’s relativity has already been disproved both theoretically and experimentally (see “Challenge to the special theory of relativity” March 1, 2016 Physics Essays). The most obvious and indisputable evidence disproving special relativity is the existence of the absolute time shown by the universally synchronized clocks on the GPS satellites which are moving with huge velocities relative to each other (see Wikipedia on GPS: The GPS concept is based on time and the known position of specialized satellites. The satellites carry very stable atomic clocks that are synchronized with one another and to ground clocks.) while special relativity claims that time is relative (i.e. different on different reference frame) and can never be synchronized on clocks with relative velocities. That is, all relativistic spacetime based theories are wrong and must be abandoned.

    As shown in my paper, the existence of aether has been proved theoretically and experimentally. Including the effects of the dynamics of the fluid aether, the computation of the shapes and formations of galaxies should be much more complicated than the situation as most physicists think that the space is empty.

  • Kurt Stocklmeir

    I liked this article. I would like Discover Magazine to ask Dr. Kroupa to write a lot of articles. A lot of pages stopped people from making comments because people were abusing people. It is important there is not any abuse because more pages may stop people from making comments. I like putting my theories on pages like Discover Magazine.
    Kurt Stocklmeir

  • Tim G. Meloche

    I agree the origin of dark matter theory originate from archaic ideas and yet vested interests continue to push it forward without use of the scientific method.
    However there is still hope for advancement in gravitational innovation. It seems to be more a matter of attitude change analogous to what occurred in the Galileo Galilei time period.
    Mainstream researches in this field need to get outside there tiny old box and look at alternatives that actually supply real world solutions to observations.
    The principles of atomic gravity first established in 2012 contain many answers mainstream seems to have overlooked.
    Nature prefers simple solutions and the principles of atomic gravity are indeed simple and yet powerful in describing how nature of gravity works both at the atomic scale and the galactic scale.
    A true scientist or interested group would take a little time make their own analysis.
    Tim G. Meloche


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