Time to overhaul Newton's theory of gravitation? Galaxy cluster models cast doubt on dark matter

For almost 75 years, astronomers have believed that the Universe has a large amount of unseen or ‘dark’ matter, thought to make up about five-sixths of the matter in the cosmos. With the conventional theory of gravitation, based on Newton’s ideas and refined by Einstein 92 years ago, dark matter helps to explain the motion of galaxies, and clusters of galaxies, on the largest scales.

Now two Canadian researchers at the Perimeter Institute for Theoretical Physics suggest that the motion of galaxies in a distant cluster is more easily explained by a Modified Gravity (MOG) theory than by the presence of dark matter.

Graduate student Joel Brownstein and his supervisor Professor John Moffat of the University of Waterloo present their results in a paper in the 21 November edition of Monthly Notices of the Royal Astronomical Society.

The two scientists analysed images of the ‘Bullet Cluster’ of galaxies made using the Hubble Space Telescope, Chandra X-ray and Spitzer infrared observatories and the Magellan telescope in Chile. The Bullet Cluster consists of two merging clusters of galaxies and lies at a distance of over 3 billion light years in the direction of the southern constellation of Carina.

This arsenal of instrumentation gave them maps of the 150 million degree hot gas between the galaxies and show the effect of gravitational lensing, where the gravity of an intervening object – here the Bullet Cluster - deflects the path of light emitted by a more distant galaxy.

Previous studies suggested that the Bullet Cluster clearly demonstrates the presence of dark matter. But when Brownstein and Moffat compared the observed gravitational lensing and distribution of gas with that predicted using MOG theory, they found no evidence for this. In other words, it is more natural to explain the appearance of this cluster using a revised theory of gravitation than by including dark matter.

MOG theory emerges from a generalization of relativity that eluded even Einstein, has been developed by Moffat for nearly thirty years and is now yielding astronomical and cosmological results. The theory has been used to successfully explain the movement of stars in over 100 galaxies and the motion of galaxies in more than 100 clusters. MOG theory may also explain the apparent anomalous deceleration of the Pioneer 10 and 11 space probes, launched in the early 1970s and now more than 12000 million km from the Sun.

The two physicists are enthusiastic about their findings. Brownstein comments, ‘Using Modified Gravity (MOG) theory, the ‘normal’ matter in the Bullet Cluster is enough to account for the observed gravitational lensing effect. In time, better observations will lead to higher resolution pictures of the systems we are studying. Continuing the search for and then analysing other merging clusters of galaxies will help us decide whether dark matter or MOG theory offers the best explanation for the large scale structure of the Universe.’

Professor Moffat adds, ‘If the multi-billion dollar laboratory experiments now underway succeed in directly detecting dark matter, then I will be happy to see Einsteinian and Newtonian gravity retained. However, if dark matter is not detected and we have to conclude that it does not exist, then Einstein and Newtonian gravity must be modified to fit the extensive amount of astronomical and cosmological data, such as the bullet cluster, that cannot otherwise be explained.’

Source: Royal Astronomical Society

Explore further

Dark matter and exoplanet discoveries win Nobel Physics Prize

Citation: Time to overhaul Newton's theory of gravitation? Galaxy cluster models cast doubt on dark matter (2007, October 31) retrieved 24 October 2019 from https://phys.org/news/2007-10-overhaul-newton-theory-gravitation-galaxy.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Oct 31, 2007
Modified gravity is a non-starter, but I applaud the out-of-the-box thinking.

Electric forces, which are billions of times stronger than gravity, are at work with respect to large scale galactic structure. I am happy to see others questioning dark matter. I am fairly certain that dark matter will be a point of embarrassment in years to come.

Regarding the Pioneer 10 and 11 anomalies, lets not forget similar anomalies affecting the Galileo and Ulysses probes. This 'mystery' has been explained for years by the Plasma Cosmology/Electric Universe camp.


Oct 31, 2007
While they are at they need to add

Einstein E=MC^2

How many times have you heard the expression light has a speed limit or as matter reached the speed of light it attains infinite mass or there is nothing faster than the speed of light.

This is knowledge we have presently and I am sure that future knowledge by scientist will look at Einstein as a cave dweller.

Some theories should have a shelf life before spoiling.

Oct 31, 2007
Finally some sane and rational scientists out there that are willing to look at other explanations besides dark matter!!! Now if we can just get some other camps of scientists - that are stuck in thinking that is way to outdated in relation to the cosmos - will they take a look at the extremophile data and finally concede that the "goldilocks zone" is a silly requirement for life...

Oct 31, 2007
Could someone summarize the MOG theory and how it differs from the original? The article danced around a definition.

Oct 31, 2007
You can find some articles by John Moffat here:

Oct 31, 2007
An expanding cosmos having a centre of mass provides a simple explanation of the Pioneer effect—see http://www.creati...iew/5181

Oct 31, 2007
holoman, do we look at Newton and Galileo as cave dwellers? No-one (rational and informed) is going to look at Einstein so negatively, even if Relativity is superseded, that doesn't mean Einstein was stupid - hell, it doesn't even have to mean that Einstein was wrong.

"How many times have you heard the expression light has a speed limit or as matter reached the speed of light it attains infinite mass or there is nothing faster than the speed of light"

Mostly I hear it from cranks trying to disprove it. You do realise that 2/3 of the statements you made in that sentence are *not the result of Relativity, and are not the consensus amongst physicists.

Light has a speed limit - yes, that is one of the basis of Relativity.
Matter approaches infinite mass as it approaches light speed - not really, this is a misunderstanding of what mass is (and the phrase 'relativistic mass' has been, as far as I know at least, largely dropped by physicists).
Nothing can move faster than light - not a theoretical impossibility in Relativity.

If you are going to say something as naive as suggesting that future scientists will look at Einstein as a cavedweller, then at the very least you shouldn't be misunderstanding and misstating his theory.

Oct 31, 2007
This comment has been removed by a moderator.

Nov 01, 2007

You need to start thinking outside the box.

Nov 01, 2007
and you need to understand whats inside the box before you start trying to think outside it.

Simple fact is, Einstein was not a cavedweller - and I'm pretty sure every worthwhile physicist on Earth will agree with me on that.

Do me a favour - do a search on the internet for all the people who have called Einstein stupid or something to that effect. Then come back, and post the results: (a) how many were scientists, and (b) how many were cranks, and (c) how many were 13 year old kids who've studied it for about 15 minutes.

(if you don't want to bother, here are the correct answers...)
(a) 0%
(b) 50%
(c) 50%
- so which are you?

Nov 02, 2007
Fred, no one is arguing that Einstein has not made a significant contribution to the understanding of the universe. What holoman is suggesting is that future developments will drawf Einstein's contributions and make them pale in comparison. In the future, the limited understanding and insight he provided may seem archaic and childish to what we know and how it works.

Nov 02, 2007
This thread is starting to sound like a Geico commericial - what's wrong with living in caves?

Are there no physicist cavemen?

Just trying to take a lighter note;-) I personally have deep respect for both Newton's and Einstein's contributions... but I think most scientists would probably also concede that we don't have the whole picture yet about how the cosmos or the forces that govern it really work. Thus, there is nothing wrong with exploring other ideas, even if they contradict the work of amazing minds of the past.

Nov 03, 2007
earls, seriously read the comment again...

{a} While they are at they need to add Einstein E=MC^2

{b} How many times have you heard the expression light has a speed limit or as matter reached the speed of light it attains infinite mass or there is nothing faster than the speed of light.
{c} Some theories should have a shelf life before spoiling.

so lets see...
(a) we should get rid of E=mc^2, suggested as if we should do it now - like there is some problem with it (the problem being obviously so clear that it doesn't need explaining)

(b) a statement which is 2/3's is a flawed representation of Relativity... future scientists won't dismiss our current knowledge of these facts, because they aren't currently knowledge

(c) suggesting that Relativity is a spoilt theory - which coupled with "cavedweller" really just about sums up the very negative tone (towards Einstein and Relativity) of the comment

as pretty as your interpretation of holoman's comment was--and I'm sure it is somewhat correct--it just doesn't match up somehow.

To sum up, I'm suggesting that holoman was suggesting a little bit more than what you are suggesting he was suggesting. But honestly, even if I've got my interpretation wrong - i actually couldn't care less. My main purpose was to point out that 2/3's of that middle statement was a flawed representation of Relativity (and while I'm here, I'll also point out that there is absolutely no good reason to overhaul E=mc^2), and I've done that.

Jun 04, 2008
There is now mounting evidence that the only observable light bending effects on rays of light have been virtually those effects that are due to an indirect, not a direct interaction between the light rays and the gravitation. An indirect interaction involving optical refraction and a direct interaction involving a theoretical space-time model between rays of light and gravitation would conceivably involve indistinguishable observational effects. The thin plasma atmosphere of the sun represents such an indirect interaction between the gravitational field of the sun and the rays of light from the stars. There is now convincing observational evidence from Astrophysics that a direct interaction between light and gravitation is yet to be observed and that the concept of microlensing may be a failed attempt to explain the lack of observation of macrolensing. The events taking place at the site of Sagittarius A* presents convincing observational evidence that a space-time model involving a direct interaction between rays of light and gravitation simply does not take place. A lack of observational evidence of optical lensing on the light from the stellar objects rapidly moving about Sagittarius A*, is clearly revealed in the time resolved images collected since 1992. Moreover, it is clearly apparent from the Astrophysics of the rapidly moving stellar objects moving about Sagittarius A* that there can be no optical refracting media in the vicinity of the galactic core, which is believed to be a super massive black hole.

For details see: http://www.extinc...ings.htm

A paper on this subject has been published in the renown refereed journal Astronomische Nachrichten, "Time resolved images from the center of the Galaxy appear to counter General Relativity", Dowdye, Jr., E.H., Astronomische Nachrichten, 328, Issue 2, 2007,pp 186 -191

Sep 19, 2008
So explain the lensing due to Abell 2218 with your theory, EHDowdye:


May 03, 2009
On Energy, Mass, Gravity, Galaxies Clusters, AND Life
A Commonsensible Recapitulation

The onset of big-bang's inflation started gravity, followed by formation of galactic clusters that behave "classically" as Newtonian bodies while continuously reconverting their shares of pre-inflation masses back to energy, and of endless intertwined evolutions WITHIN the clusters in attempts to resist this reconversion.

A. "Heavyweight galaxies in the young universe", at

New observations of full-grown galaxies in the young universe may force astrophysicists to revise their leading theory of galaxy formation, at least as it applies to regions where galaxies congregate into clusters.

B. Some brief notes in "Light On Dark Matter?", at


- "Galaxy Clusters Evolved By Dispersion, Not By Conglomeration"
- Introduction of E=Total[m(1 D)]
- "Dark Energy And Matter And The Emperor's New Clothes"
- "Evolutionary Cosmology: Ordained Or Random"
- "%u201CMovie%u201D Of Microwave Pulse Transitioning From Quantum To Classical Physics"
- "Broken Symmetry" Is Physics' Term Of Biology's "Evolution"
- "A Glimpse Of Forces-Matter-Life Unified Theory"

C. Commonsensible conception of gravity

1. According to the standard model, which describes all the forces in nature except gravity, all elementary particles were born massless. Interactions with the proposed Higgs field would slow down some of the particles and endow them with mass. Finding the Higgs %u2014 or proving it does not exist %u2014 has therefore become one of the most important quests in particle physics.

However, for a commonsensible primitive mind with a commonsensible universe represented by
E=Total[m(1 D)], this conceptual equation describes gravity. It does not explain gravity. It describes it. It applies to the whole universe and to every and all specific cases, regardless of size.

2. Thus gravity is simply another face of the total cosmic energy. Thus gravity is THE cosmic parent of phenomena such as black holes and life. It is the display of THE all-pervasive-embracive strained space texture, laid down by the expanding galactic clusters, also noticed within the galactic clusters in the energy backlashes into various constructs of temporary constrained energy packages.

3. "Extrapolation of the expansion of the universe backwards in time to the early hot dense "Big Bang" phase, using general relativity, yields an infinite density and temperature at a finite time in the past. At age 10^-35 seconds the Universe begins with a cataclysm that generates space and time, as well as all the matter and energy the Universe will ever hold."

At D=0, E was = m and both E and m were, together, all the energy and matter the Universe will ever hold. Since the onset of the cataclysm, E remains constant and m diminishes as D increases.
The increase of D is the inflation, followed by expansion, of what became the galactic clusters.

At 10^-35 seconds, D in E=Total[m(1 D)] was already a fraction of a second above zero. This is when gravity started. This is what started gravity. At this instance starts the space texture, starts the straining of the space texture, and starts the "space texture memory", gravity, that may eventually overcome expansion and initiate re-impansion back to singularity.

D. Commonsensible conception of the forces other than gravity

The forces other than gravity are, commonsensibly, forces involved in conjunction with evolution within the galactic clusters:


The farthest we go in reductionism in Everything, including in Life, we shall still end up with wholism, until we arrive at energy. Energy is the base element of everything and of all in the universe. At the beginning was the energy singularity, at the end will be near zero mass and an infinite dispersion of the beginning energy, and in-between, the universe undergoes continuous evolution consisting of myriad energy-to-energy and energy-to-mass-to-energy transformations.

The universe, and everything in it, are continuously evolving, and all the evolutions are intertwined.

E. PS to "On Cosmic Energy And Mass Evolutions"

As mass is just another face of energy it is commonsensible to regard not only life, but mass in general, as a format of temporarily constrained energy.

It therefore ensues that whereas the expanding cosmic constructs, the galaxies clusters, are - overall - continuously converting "their" original pre-inflation mass back to energy, the overall evolution WITHIN them, within the clusters, is in the opposite direction, temporarily constrained
energy packages such as black holes and biospheres and other energy-storing mass-formats are precariuosly forming and "doing best" to survive as long as "possible"...

F. From "Strings Link the Ultracold with the Superhot"


"Perfect liquids suggest theory%u2019s math mirrors something real.

When the universe was very young, and still superhot from the aftermath of the Big Bang, plasma should have been the only state of matter around. And that%u2019s what scientists at Brookhaven expected to see when they smashed gold ions together at 99.99 percent of the speed of light using a machine called RHIC (for Relativistic Heavy Ion Collider). RHIC physicists thought the ion collisions would melt the gold%u2019s protons and neutrons into a hot plasma of quarks and gluons at a temperature of a trillion kelvins, replicating conditions similar to those a microsecond after the birth of the universe. But instead of a gaslike plasma, the physicists reported in 2005, RHIC served up a hot quark soup, behaving more like a liquid than a plasma or gas."

G. The expectation of Brookhaven scientists was a bit unrealistic

The "aftermath of the Big Bang" lasted much less than 10^-35 seconds. This is evidenced by the fact that "Gravity Is THE Manifestation Of The Onset Of Cosmic Inflation Cataclysm":


With all respect due to the scientists at Brookhaven it is unrealistic to expect that they can recreate the state of pre big-bang energy-mass singularity. Commonsense is still the best scientific approach.

H. PS To "Gravity Limits Link Ultracold And Superhot": Our Inability To Create Singularity

a. From "Strings Link the Ultracold with the Superhot"

A new truth always has to contend with many difficulties,%u201D the German physicist Max Planck said decades ago. %u201CIf it were not so, it would have been discovered much sooner.%u201D

b. IMO gravity is attempted reversal of inflation

To me, a simple uninformed one, E=mc^2 is a derived formula, whereas E=Total[m(1 D)] is a commonsensical descriptive concept.

I intuitively regard both the ultracold and superhot liquids as being in a confined space and "striving but unable" to overcome D, to render D=0.

I also intuitively regard our accelerated collisions smashups as attempted "reverse inflations" in the sense that Newton's law of universal gravitation seems to me as "reverse inflation".

Dov Henis
(Comments From The 22nd Century)
Life's Manifest
EVOLUTION Beyond Darwin 200

Jun 05, 2009
Posted (1 plus D)
prints out here as (1 D).

Should be (1 plus D)

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more