Ever since it was discovered that the rotational dynamics of spiral galaxies were inconsistent with the observed mass of those galaxies, it has been postulated that missing mass or dark matter was responsible.
With fellow staff-member Kent Ford, astronomer Vera Rubin announced at a 1975 meeting of the American Astronomical Society the discovery that most stars in spiral galaxies orbit at roughly the same speed, that this observation implied that galaxy masses grow approximately linearly with radius well beyond the location of most of the stars (the galactic bulge). Following that announcement, Rubin presented her results in an influential 1980 paper.
Although Rubin’s observations and subsequent explanation(s) was (were) initially met with skepticism, they have persisted through the intervening decades as an open question. Add to this the discovery of Dark Energy, that at cosmologically significant distances, the expansion of the universe is accelerating, a phenomenon inconsistent with Hubble’s expansion law. In fact the 2011 Nobel Prize in Physics was awarded to an Australian and two Americans for their groundbreaking observations of Type Ia supernovae at cosmological distances in this regard.
Our current, widely recognized model of the Universe, LambdaCDM, tells us nothing about the nature of dark matter and dark energy. We only know about them because of the gravitational effects they have on observable matter.
Enter astrophysicist and Post-Doctoral Research Associate Dr. Jamie Farnes of Oxford University’s Department of Engineering Science. Published in the latest edition of Astronomy and Astrophysics, Dr. Farnes proposes, in essence, that Dark Energy and Dark Matter are two sides of the same coin, that a fluid of negative mass is responsible for the heretofore inexplicable, enigmatic and mysterious behavior of spiral galaxies, observational anomalies of galaxy clusters and the large-scale expansion of the universe.
There is a another phenomenon that was once thought to behave as the result of an ubiquitous “invisible fluid“, a fluid that was pervasive, undetectable, unobservable but yet seemingly manifest everywhere, something much like what is described by Oxford’s Dr. Farnes: light. It was postulated that this “invisible fluid” did not interact with anything and was undetectable but yet the idea persisted.
Any freshman physics or astronomy student is familiar with the famous Michelson-Morley experiment and the cohesive set of equations known today as Maxwell’s equations. The brilliant Scottish Physicist James Clerk Maxwell brought together four seemingly disparate principles of Electromagnetic Theory and demonstrated unequivocally that light is the propagation of an electromagic wave with its speed a constant of nature.
The Michelson-Morley experiment measured the speed of light in all directions and, to within the precision available at the time, determined that its speed is invariant, forever dispelling the idea of a pervasive Aether. The speed of light would play a central role in Einstein’s 1905 publication of his Special Theory Relativity, published less than twenty years after Michelson and Morley’s 1887 experiment and 43 years after Maxwell’s 1862 publication.
Prior to Maxwell and Michelson and Morley, it was believed that a pervasive and invisible Aether was the medium of transmission for light, a holdover and seemingly necessary aspect to any theory that described it since any wave, based on the classic idea of a wave, required a medium.
There are many fundamental contradictions and inconsistencies in this latest attempt to explain “dark matter” and “dark energy”, not the least of which is “matter creation“, a postulate inherent in the “Steady State” theory of the late Fred Hoyle and others, a model inconsistent with the Big Bang. Furthermore, any theory that includes notions of a “fluid” on cosmic scales has to be overly scrutinized. Moreover and perhaps the strongest reservation is that answers to such important questions cannot be answered by a single study or publication.
Keplerian Rotation Curves
Galactic rotation curves can be explained without using Dark Matter by a high school physics student. That many models and illustrations continue to use Keplerian arguments to suggest that Dark Matter must exist because the rotation curves don’t follow Keplerian rotation curves is manifestly disingenuous as well as scientifically and academically dishonest (see the “Expected from the visible disk” curve in the featured image above). Galactic rotation curves could never be Keplerian because a galaxy is not a point mass – we’re making these measurements from within the galaxy when designing and postulating these models! Gravitational sources are modeled as point masses with their orbits and trajectories reliably and predictably modeled as Keplerian precisely because they are considered point masses! A galaxy is an extended mass whose gravitational effect has to be continuously integrated with increasing distance from the center. Keplerian orbits when discussed in a galaxy-scale context could only be valid for objects orbiting a galaxy at a distance where the galaxy could be considered a point mass.
It’s also instructive to point out that many great physicists of recent notoriety such as Richard Feynman never once mentioned Dark Matter. When one considers some of the proposals for Dark Matter research and grant funding as it persists today, this phenomenon could be construed, perhaps, as attempts to leverage the ignorance of funding agencies or sources to continue endless research with increasingly ridiculous proposals. The Oxford study discussed in this article not withstanding, some of the proposals of late have gone from the ridiculous to the absurd and could be considered scandalous at this point. Any credible professional scientist who supports any of them should take a long, hard look at what he or she is endorsing.
The theoretical rotation curves for the Milky Way galaxy are illustrated here. The rotational velocity of the sun at the 8 Kpc point (blue curve) is consistent with observation with he pseudo-Keplerian curve featured in orange. The blue curve is modeled as an
“integrated mass” as described above. Additionally, the blue curve is consistent with the rotation velocities of points exterior to the sun in the Milky Way and of all major galaxies such as M-33, illustrated above. Note the convergence of the two curves at the edge of the galaxy, an expected outcome of this model.
Sorry, but the Oxford study falls short and thus, we still have no plausible explanation for the anomalous rotations of spiral galaxies and the large-scale expansion and behavior of the Universe. A possible explanation that has persisted since 1983 is MOND (Modified Newtonian Dynamics – a modification of Newton’s Laws of Motion and his Gravity Law at great distances) and WIMPs (Weakly Interactive Massive Particles) but that’s it.
It may well be that we will never fully understand the true nature of dark matter or dark energy much in the same way that fleas, exploring the huge body of an elephant, have no idea of the true shape and nature of the animal. Although dark matter and dark energy are known unknowns, in the sense that we know they exist and can observe their effects, we may forever be limited to that scope because of the universe’s unknown unknowns.
Our brains have served us well, having evolved in a 3-dimensional world in accordance with natural pressures and our ability to learn, to communicate and to build languages and societies for the greater good of the many. To survive and to prosper as a species on the plains of Africa, ultimately to become the dominant species on the planet is one thing but to plumb the depths of space and time in a 4-dimensional universe is quite another. Nature hides her secrets well but she is not perverse so yes, we have to still keep looking.
Related article: Dark Matter – Chasing A Ghost That Doesn’t Exist. Please note, since the pursuit of science is, at its heart, a search for the truth, I will continue to write and comment on this topic.
Read more about Dr. Farnes work at: https://phys.org/news/2018-12-universe-theory-percent-cosmos.html
Imagination is more important than knowledge
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