Solution to the Galaxy Rotation Problem, without Dark Matter

Basically yes; entirely no. I have to trust the math, because I can not do it. If the math is in error, that would be the reason for a counter argument. The math is good I’m sure, so I scim past the equations that I am not capable of solving.

I do understand it does not address what I am proposing. It is another notion entirely. Most Interesting to me is that it shows there is no consideration, or comparison of the effects that Gravity Time Dilation will show between the Schwarzschild radius vs. 5000 ly 10,000 ly/ 25,000 ly/ 50,000 ly, etc. even at this level of mathematical modeling.

I am currently learning, outlining and gathering observable data, to be able to show a comparative analysis of this effect at several locations radially throughout Andromeda. I am gathering the needed parameters, but there are many things to consider, before even starting the calculations. First and foremost, Gravity Time Dilation ‘can’ account for Redshifts anywhere between Zero and 3.00, or 300,000 Km/s. This would be clear at the event horizon of a Supermassive Black Hole, such as is theorized currently within the galactic cores of spiral Galaxies. From that point outward the Time Dilatation will dilute, but as too how fast, and how far the effects need to be considered is the question. One consideration is of course the initial mass estimated within the event horizon. The initial density is the biggest factor when considering the maximum value for Time Dilation of a single object orbiting nearby (nearby might be within 5 ly’s). Due to the Gravitational Time Dilation equation, the density of the core has the largest impact, because it is radius, over mass. The closer we are to the center of an orbited object vs. its mass, the more exponential the effect. This is reduced by an inverse square, simply meaning that as we travel twice the radius, the effects quarter, exactly as any other Gravity field equation. We need a best estimate of the surface radius so we can use an initial mass, then we can do the calculations outward from there at several benchmarks. Andromeda’s Black Hole is currently estimated at 4.3 Million Solar Masses. We could actually use the Gravity Time Dilation equation to determine the radius of this Black Hole, by finding at what radius this mass can keep at the speed of light.

The effects of this will drop of rather rapidly as we travel outward from the galactic core, but another estimate would need to be made of the ‘new’ total mass contained within the radius of any object’s orbit that we observe. The overall mass within that sphere becomes the new mass that should be used to deduce the total effects of Time Dilation from light emitted from a particular object. Though our initial mass 4.3 million Solar Masses, and not the density, will determine the overall ‘reach’ of the Black Hole’s Gravitational Time Dilatation/Redshift for a particular object, the successively added masses within each specimen’s orbit will increase at each benchmark radially.

For instance, another radius we might consider while calculating for a single orbiting object would be that of the galactic bulge, roughly 5,000 ly. The total mass within that orbital sphere would be around 1.67 Billion Solar masses. This is the new Mass to Calculate from that radius, and so on. Even some of the mass located outside that particular orbital sphere, would add to the equation, but not to show what is needed to prove what I am trying to show here. It will be close enough without adding this to the complexity initially at least.

 

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Thanks to Gabana, he posted this in the regular forum. Good find. http://arxiv.org/pdf/1005.2826.pdf This begins to address my exact question.

 

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You mean you want someone to mathematically formalise an idea you have?

Unless it is an extremely high level idea it is not going to work like that because the details are guided by the mathematical structure of any formulation, you cannot really decide apriori what the implications of an idea are. This is why people like Farsight have such a flawed approach, they assume their conclusions follow from their starting assumptions and someone else can just fill in the maths. Unfortunately they have no justification for thinking their conclusions follow from their assumptions.

If you have enough mathematical capability to follow the arxiv papers posted by Alex and yourself then you've got enough under your belt to be getting on with things. The papers are by no means 'advanced' on the scale of general relativity but still involve many common mathematical methods (solving Poisson's equation for instance) used in cosmology and physics in general.

Yes, an outright dismissal of the idea of modifying gravity would be a mistaken approach. However, there has been significant exploration of various modifications and they all have issues equal to or greater than dark matter. If someone has to introduce a new kind of matter to make your modified gravity model fit just to avoid accepting dark matter than something has gone wrong in their thinking (like conspiracy nuts who assert magical technology to fake the Moon landings in 1969, technology more complicated than the technology needed to go to the Moon!).

Modifications to gravity models is not something which should be dismissed but once a reasonable amount of exploration has been done then it shouldn't be given undue weight.

Fair enough, asking for someone to walk you through a particular standard result or explanation so you can understand it is fine, a much more worthy reason to ask for the disproof than attempting to shift the burden of proof.

There's nothing wrong with people trying to see if there's reason to modify gravity. If no one had bothered to accurately measure the behaviour of Mercury we'd never have noticed there's a mismatch with Newtonian gravity. That's being guided by the evidence when a non-insignificant fraction of dark matter detractors (mostly internet hacks) have an agenda, ie "I dislike the concept therefore I'll always push alternatives!", to do the reverse, to guide the evidence.

Fair enough, I have plenty of time for people who want to go through mainstream stuff to understand it. Whether you then go on to not agree with it is irrelevant, taking the time to understand it first is intellectually honest.

So is there some specific mathematics or physical model related thing you're wondering about? You implied you followed the papers you and Alex posted. Did you? And if you didn't is there some part of it you're particularly confused by? Or do you want a less technical summary of what it is they are trying to do?

 

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If you look at gravity, there are two affects going on. The first can be defined by relativity and the space-time well. The second aspect is connected to gravity induced pressures which can alter the physical phases of matter.

The second aspect has less to do with space-time and relativity, and more to do with actual changes in distances and orientations between atoms. For example, iron is a solid in the earth's core at temperatures it would be a gas on the surface. The solid iron of the core could be simulated on the surface with mechanical pressure and high temperature, even within the lower space-time contraction at the surface. It is not dependent on relativity as it is on pressure regardless of source. Gravity just so happens to be a major source of pressure.

What pressure and phase changes do is lower the entropy of matter. If we pressurize gaseous water vapor via gravity to form liquid water, the entropy changes by - 108.951 J mol-1 K-1 (100 °C). What this all means is gravity induced pressure lowers the entropy within the universe, even though the entropy of the universe has to increase. The need to net increase the entropy, results in connected secondary affects such as rotations and differentiations. The rotation and differentiation of stars has to offset the loss of entropy due to gravity. The rotation profile of our galaxy tells us the entropy profile induced by gravity induced pressures.

 

Or un-formalize it, yes. Either this will help make my hypothesis better, or disprove it altogether.

To determine whether an idea is “extremely high level” or not? I suppose we could say, the higher the expertise required for putting an idea to rest, the higher the level, agreed?

As for as the implications are concerned, if what I propose is true; the conclusions reach far beyond Andromeda. I’m certain you and I both understand this. This is not by my design, or assumption, but is the logical end of what I am asking we take a look at. This is also why it should be important to us, but why continue if this very first step has no value or truth. Math is one way at the truth, but not the only way. It has to agree with any scientifically valid truth, but only as a partner. Math can only describe reality, or agree with it. It is not the only basis for finding solutions.

I am not looking for advanced General Relativity math, unless you consider the Time Dilation Equation advanced. It is advanced to me, and that is why, as previously stated, I am seeking a math partner. I understand that the papers do not address my hypothesis, only a brief mention that they both agree on dismissing Special Relativity as it concerns Kinematic Time Dilation. Neither the anti-dark matter, nor the pro-dark matter publications wish to address frames of reference or alternate observers because the relative observations have no bearing on their conclusions. Neither of these two ideas will be affected by Special relative observations, or math; nor will mine for that matter. The speeds are too far away from the speed of light for this to affect any conclusions using this math. Does it matter at some point? Yes, but all discussions regarding this modeling of the galaxies, disregards SR every time it states, “in non-rotating bodies”. That is because we have found, while trying to solve UTC, we realized that the effects of the rotation, do have a greater affect at the Equatorial regions. However, as in Earth as example, the equatorial regions are swollen due to centrifugal forces, they are then, therefore, farther from the center of mass enough that SR and GR equate themselves, rendering either as benign. So we speak of non-rotating bodies, because it is acceptable for the big questions, and large modeling.

Agreed, that would be entertaining to add a new kind of matter to disprove a new kind of matter. Dark matter is old I suppose, but Dark matter by a different name would be fun, no? Though I don’t understand how Dark Matter is in any way superior to a modification of gravity that acts differently over time, or scale. This Gravity Modification over time or scale can be mathematically described, equally as well as Dark Matter couldn’t it? How many trillions of dollars are we planning on spending seeking additional proof of something that simply works mathematically? To me they are quite equal, though one has far less funding.

Agreed.

That is the goal.

Agreed. But this could also be said; “ ie "I dislike the (alternatives) therefore I'll always push (the concept)!"”

Excellent, I will either become a more ardent supporter of the current model, or a more enthusiastic detractor; in time.

I wouldn’t mind a basic layman’s description of what the pro-Dark Matter counter argument is saying, or what the anti-Dark Matter original work is trying to prove, in your words, but I don’t think either of these applies directly to my original OP. The most important find for me is the last paper posted by the new member. What is says to me is that my ideas are mathematically possible. It does not go near far enough as to say, here is why it is true, or here are further examples or questions that may be resolved by this. It only proves mathematically that Gravitational Time Dilation can solve the Galaxy Rotation problem, not that it does. It is not so bold, but I do appreciate their work no doubt.

http://arxiv.org/pdf/1005.2826.pdf

 

It is seldom someone writes from the depths of their being as Scott has done here. I really do hope AN and PRenner work along with you on your path of discovery.

 

Most readers, I figure, do not follow a link provided in most of our posts here. I personally care more about the responses and discussions so I frequently ignore the links and read on. I might follow a link, if I have doubts about what is claimed, or if the source document appears valuable to the discussion.

That being the case, here two excerpts from my favorite astrophysics publication, which have some relevance to this thread, and my opening remarks.

“At this stage, either we suppose that the previous calculus is correct or not. In this
paper, we postulate that the Newton’s dynamics are correct. We also know that the
restrictions on variations in the gravitational constant are strict [11]. Nevertheless, we
want to provide a solution for the problem of the motion of stars in galaxies without
using the assumption of the dark matter.”

This is an honest approach I think. The intentions are stated clearly within the text and agree with my original hypothesis.

“The Newton’s theory is only an approximation of relativity. Something happens in
relativity which is not taken into account: this is the gravitational time dilation. We
mean the gravitational time dilation due to the changing gravitational field, not the
relativistic time dilatation due to the velocity of the stars which is not significant.”

I have not “assumed” that such an "obvious" solution has not been taken into account, but as yet, have found it NOT in use. We find this group asserting that GTD has NOT been “taken into account.” The publishers and their peers have found the same as I. Evidence for (GTD) being used in the current model is simply not there. I find no trace; nor did these fellas. If you have any record please share. If you have any counter arguments to this publication, please share.

I am dropping one sentence from my initial abstract, so here is the new final statement.

Hypothesis:

Gravitational Time Dilation, described by General Relativity, sufficiently solves the galaxy rotation problem, without the need for dark matter. Time speeds up progressively from the galactic core outward, as predicted in GR, giving the appearance of higher radial velocity. By keeping Kepler’s Law and applying Gravitational Time Dilation no Dark Matter is needed, and no alternative, or progressive, gravity interprtation is needed.

 

From your paper:

From the conclusions:

Perhaps direct evidence is at hand: http://www.space.com/19845-dark-matter-found-nasa-experiment.html

This is from the particle physicists, not the astronomers.

 

I've been reading the reports on this too AlexG. We'll have to see what the hype is huh? Sounds interesting. Here's an article from just yesterday.

http://news.yahoo.com/higgs-boson-particle-may-spell-doom-universe-152236961.html

 

Scott, I ran into this article on arxiv, titled "The Real Problem with MOND".

http://arxiv.org/pdf/1112.1320v1.pdf

Of particular interest is the graph on page 5,

(same graph, clipped from a different source)

View attachment 6105

FIG. 1: The power spectrum of matter. Red points with error bars are the data from the Sloan
Digital Sky Survey [9]; heavy black curve is the CDM model, which assumes standard general
relativity and contains 6 times more dark matter than ordinary baryons. The dashed blue curve is
a “No Dark Matter” model in which all matter consists of baryons (with density equal to 20% of
the critical density), and the baryons and a cosmological constant combine to form a flat Universe
with the critical density. This model predicts that inhomogenities on all scales are less than unity
(horizontal black line), so the Universe never went nonlinear, and no structure could have formed.
TeVeS (solid blue curve) solves the no structure problem by modifying gravity to enhance the
perturbations (amplitude enhancement shown by arrows). While the amplitude can now exceed
unity, the spectrum has pronounced Baryon Acoustic Oscillations, in violent disagreement with
the data.

 

You didn’t just run “into this article on arxiv”. It was destiny . We’ll let that expand into the philosophy department, but nonetheless, nice find and thanks for posting it.

So far I gather from this that MOND can not solve the Galaxy Rotation problem without Dark Matter, or another type of matter in its place, as AlphaNumeric alluded to a few posts ago. Is that correct? That is; though MOND can explain some questions in our current model, it inadequately solves the Galaxy Rotation Problem (GRP?) and the CMB. I did ask Robittybob1 if his math can address the Galaxy Problem, but I would rather know, especially since your discovery here, if MOND most accurately describes what it is that he is doing within his work.

From your paper,

“Gravitational potentials in the cosmos are deeper than expected from observed visible objects,
a phenomenon usually attributed to dark matter, presumably in the form of a new fundamental
particle. Until such a particle is observed, the jury remains out on dark matter, and modified gravity models must be considered.”

I wish, for my own personal agenda, that this team would have said, “Until such a particle is observed, the jury remains out on dark matter, and (Alternative) models must be considered.”

 

Scott if there is any connection between "my work"and this flat galaxy rotation speeds it would have to work something like the following, (but even to me it would seem such an unusual solution that I'm reluctant to say it). But I'll try and remember it is just the earliest of all propositions.
Every star in a galaxy has its own gravitational relationship to the central galactic mass (predominantly within the central black hole).
Each "gravitational relationship" is determined by the amount of gravitational radiation it has lost and how much of the gravitational potential has been paid back. Like the Gravitational Constant (G) between two objects A and B can be different than between A and C or B and C, so the missing mass is entirely in the black hole, with the entire mass and G of the black hole still holding the outer stars but a reduced G for the inner stars.
"The Mystery of Dark Matter (Chapter 2/4): 39 Billion Missing Suns."
http://www.youtube.com/watch?feature=player_detailpage&v=OzrxXxkdN1w

With this scenario there would not be the need for dark matter, but the matter required is in the black hole but is hidden because G is lowered toward the inner stars but still maintained toward the outer stars.

 

This isn't as silly as it first seemed for it simply means that G varies with and in proportion to the distance out from the center of the Galaxy. Full strength in the outer portions and lesser the further in. This then allows the speeds of the stars to remain at near constant speed, as we were seeing with the binary.

 

If we wish understand how to solve the Galaxy Rotation Problem as Emmanuel Moulay has done here: http://arxiv.org/pdf/1005.2826.pdf then let’s review why this works.

From WIKI, “While gravitational redshift refers to what is seen, gravitational time dilation refers to what is deduced to be "really" happening once observational effects are taken into account.”

Though Gravitational Time Dilation (GTD), and Gravitational Redshift (GRS) use the same math, If we are to understand what is happening on the ground, or “Really” happening with the galaxies, we have to understand how our observations are being made in the first place.

We measure the (local) proper motion of the stars orbiting the central mass of a galaxy by using Doppler Shift, after we have first removed the overall redshift caused by the proper motion of the galaxy in relationship to Earth. This works best for galaxies that are tilted away from us, or more of an edge view, looking across the galaxy. On opposite sides of the galaxy, one will skew red and the other, blue.

If our perspective is directly over top the galaxy it will be a more perfect circular shape and we cannot use Doppler Shift to infer any radial velocity because Doppler Shift measurements only apply to objects moving toward or away from us. We can only use geometry and distance traveled over long periods of time to deduce the orbital rotation period of stars in this category. It takes approximately 2.25 Million years for the sun to orbit the central Milky Way, so you see we have very little data provided by simply ‘watching’ stars orbit in a galaxy. We have very little time at this scale. Even the fastest stars found orbiting Andromeda will take 100 Years to orbit the central Black Hole at 2.2 Million Miles per Hour. At this rate, we will be very slow at physically tracking, mapping and observing the relationship between how stars near the core behave differently compared to the stars in the far outer regions of Andromeda.

If we could compare our Doppler Shift calculations readily with pure geometry and distance over time, our observations will agree with our current findings. Both will agree that the expected orbital velocities near the outer regions are moving too fast compared to our expected orbital calculations near the center.

Both our physical geometric method, and our Doppler Shift method need to be adjusted for the predicted effects of Gravitational Time Dilation/ Gravitational Redshift, which will vary from each relative region from the center of the galaxy outward. This part of the Redshift, or Blue shift respectively, needs to be eliminated from observations as the effects are increased proportionally from each region light is being emitted. Once we have done this properly, the predicted Keplerian orbital relationship is restored, and there is no additional, Nonbaryonic, mass needed to solve the variability in rotation.

The Galaxy Rotation Problem is then, not an indicator of missing mass, but is a physical expression of the Baryronic mass within each particular region of the galaxy. Proper Time then, is nearest the most proper frame far away from any Gravitational influence. Though all local time work within their proper frames mathematically, if we are to observe from a remote location (as in Earth toward Andromeda) the Gravitational Time Dilation will be observed and is measurable from one Gravitational Region to another. This is the main difference between Special Relativity and General Relativity, within the Equivalence Principal. All Observers agree with the time change. The most proper Keplerian orbits then will be most correct, as observed by us, as we view the most outer regions of an observed Galaxy.

While viewing the centermost stars, time slows most shifting the escaping emitted light from these stars toward the Redder end of the spectrum. This is due to the slowing effect of the time and the actual orbital velocity being changed, but not the speed of the light being emitted. In order for each region to have its own proper time the wavelength of the light has to shift to accommodate this. To view the outermost stars, time speeds up most, so the light will be emitted from these regions as less red, or more toward the blue end of the spectrum. The Galaxy Rotation Problem, or paradox, is not a problem at all then. It is simply an artifact, and more observed proof, of General Relativity.

Interesting facts,
ANDROMEDA: “Spectroscopic studies have provided detailed measurements of the rotational velocity of M31 at various radii from the core. In the vicinity of the core, the rotational velocity climbs to a peak of 225 kilometres per second (140 mi/s) at a radius of 1,300 light-years (82,000,000 AU), then descends to a minimum at 7,000 light-years (440,000,000 AU) where the rotation velocity may be as low as 50 kilometres per second (31 mi/s). Thereafter the velocity steadily climbs again out to a radius of 33,000 light-years (2.1×109 AU), where it reaches a peak of 250 kilometres per second (160 mi/s). The velocities slowly decline beyond that distance, dropping to around 200 kilometres per second (120 mi/s) at 80,000 light-years (5.1×109 AU). These velocity measurements imply a concentrated mass of about 6×109 M☉ in the nucleus. The total mass of the galaxy increases linearly out to 45,000 light-years (2.8×109 AU), then more slowly beyond that radius.”

 

That's the last sentence in the wiki article, which, as far as I can tell, says that gravitational redshift is caused by gravitational time dilation, and furthermore, gravitational redshift is accounted for. (according to the wiki article on redshift)

This certainly hasn't been established.

I'm really curious about what the particle physicists come up with.

 

It is not accounted for in most of our observations I would say.

I am as well, but it reminds me of the discovery of life on Mars hype. We were waiting to hear what life had been found and what we ended up with was the possible fossilized remains of what might be biological bacteria; or not

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Though I appreciate that the extra excitement from the main stream media coverage, getting others to be interested in such things, I’m apprehensive about how profound the findings will be.

I found this cool kind of simplified breakdown of gravitational lensing, and shearing. It's worth a moment, and I'm sure you'll appreciate it. The discussion that follows is also rewarding. I'm only partially throught that part.

http://scienceblogs.com/startswithabang/2011/04/20/how-gravitational-lensing-show/

 

I read that paper http://arxiv.org/pdf/1005.2826.pdf. I just can't believe there is that much time dilation in the Milky Way Galaxy. So we are living in a Gravitational Time Dilation Zone! For we are part of that Galaxy. What effect does that have when it comes to us looking at the rest of the Universe?

 

Actually I meant it the other way around, ie the high level discussion doesn't burrow down into the details, it is just throwing ideas/concepts around in an arm wavy manner, though I can see why that might not be how many people interpret the phrase.

Mathematics is a way of formalising logical arguments, since it is the study of logic based constructs. If you want to do science then you have to work with logic and rationality when considering the consistency of ideas and experiment or the implications of an idea.

Science is based upon reason and evidence. Maths cannot provide the latter, observations of reality do, but it is pretty much equivalent to the former. If you make logical deductions then you can write them formally using mathematics. If you're considering consistencies then you're doing logic and can write it mathematically. Without logic and reason you have no science and mathematics is the formalisation of logical procedural thought.

Without at least some familiarity with mathematics you're going to struggle to really get anywhere even if you have a 'maths partner'. It's easy to spit out random ideas which are logically inconsistent or whose formal definition and derivation is highly non-trivial. If you do not have some familiarity with logic and mathematics then you are going to be unable to temper any imagination you have with rationality. Likewise for physics, if you're going to start making suppositions about reality then it is important you're vaguely informed in regards to it.

Both of issues are why people like Farsight get laughed off forums. He has no experimental data to hand and has no personal experience doing or analysing experiments so he has no information pertaining to the physical phenomena he asserts things about. It's like me asserting I know what your shoe size is, given I've never met you and you've never told me it would be daft for me to make claims about it. Then none of his claims have any formalisation so he has no idea if his conclusions follow from his premise. It's easy to assert implications of postulates but unless you actually derive them you're on thin ice. Hence why tempering imagination with some mathematical experience is useful, even if the mathematics you know doesn't end up in your work.

To give an example consider the following 'theory' : Postulate A : All men are green. Postulate B : Amy is female. Postulate C : Dave is male. Conclusion : Amy is orange. Of course the problems with this are immediate, the conclusion does not follow from the postulates. It isn't inconsistent with the postulates either but that is another issue. Since it isn't inconsistent we therefore have it as another postulate, not a conclusion. When someone's conclusion is another postulate they don't have a model, they have a list of personal opinions.

If someone didn't understand even basic logic or how to combine the postulates they might not realise the conclusion is flawed. Changing this model to include a load of buzzwords wouldn't help matters either. Pretty much every internet physics hack falls into this trap, their conclusions are actually more postulates.

The deformation of the Earth due to rotation has been included in experiments testing relativistic predictions. High precision mapping of gravitational and electromagnetic anomalies due to crust variation, mineral composition and topography has been done by both military groups (to improve their weapon guidance methods) and private sector groups (oil prospecting, it discovered the crater of the asteroid which killed the dinosaurs!). Heck, we've even done it for the Moon.

This is why it is important people familiarise themselves with the mainstream take on things before they try to argue against it. If you don't know what experiments have been done by who looking for what when and the resultant models then you don't know what you're arguing against. The best way to see the problems with a model is to learn it in great detail. I've said it a number of times on the forum but I'm certain I know more problems with mainstream physics than any pseudo-science peddler.

'Dark matter' is such a wide label that pretty much anything new will fall under that heading because if it were not dark (ie it interacted with photons) we'd have observed it visually long ago.

The existence of new particles is not only not an issue but is expected. It would be the height of hubris to think we've exhausted the universe's selection of particles. We're able to do experiments up to \(10^{12}\) electron volts of energy, the Planck scale (where quantum gravity can no longer be ignored) is \(10^{15}\) times higher than that. We've only been scratching the surface of the universe for a few hundred years, finding new stuff is expected (which is why people like Sylwester who claim he's explained everything is so laughable). Modifying gravity less so because we've already seen the ability GR has to model so many phenomena, if it had a significant modification it would have to be rather clunky in its action. It isn't like going from Newtonian to relativistic, where the latter basically turns into the former at low velocity, it would be a more convoluted modification.

Trillions? Not quite. The LHC cost 10 billion and the James Webb telescope about 7 billion. Compare that to the planned cost of the F35 fighter program, 400 billion, or the estimates cost of the nuclear arms race since 1945, which is about 10 trillion. Besides, the money isn't just about getting some readings about some new particles, it is also about the spin off technology. The technology which is used by the LHC didn't exist when the LHC was first proposed. A significant amount of the budget went on paying for research into things like large scale refrigeration techniques, the behaviour of superfluids, large scale design and manufacture of superconductors, high precision electromagnetic field generators and sensors, new ways of data collection (ATLAS pumps out 1000 terabytes of data a second!), data management, data transmission and data processing via distributed computing and supercomputing clusters. These filter down into more consumer level products. It's similar to how DARPA gets 3 billion dollars a year and puts a lot of it into blue sky research or quite tenuous future technologies, the applications are generally more diverse than people initially imagine.

As for why we do these experiments in the first place.. simply having two models which predict the same for a particular phenomenon isn't enough, you need to understand whether they are both valid elsewhere since they will undoubtedly disagree about something (otherwise they are just the same idea written in different ways). Newtonian gravity worked for 250 years but people kept testing it until it failed and that led to relativity. Electromagnetism worked for 50 years until it was broken and scientists ended up developing quantum mechanics. If someone had said in 1900 "Maxwell's electromagnetism explains how magnets work, don't bother doing any more experiments" we'd never had got Planck's work which led onto quantum mechanics which led to electronics which led to computers. In 1900 people thought the electron was of no practical use, now models of its dynamics form the basis of our entire civilisation thank to electronics and electricity.

Can you be more specific, is there something from say the Wikipedia page on dark matter you don't get?

 

The author makes an assumption then jumps to conclusions without a heck of a lot of thorough reasoning. The paper doesn't convince me but I'm a bit green on the topic as yet to really see the faults in it.
Did it totally convince you Scott?

 

I have thought this should be considered since what I think has been shown (predicted) by GR is universally true, and should be applied. The most proper Time Frame would be near Zero Gravity. I would revise one of my previous statements where I said our most accurate observations would be farthest away from the central mass of a galaxy. In retrospect, the best observations would be 25,000 LY from the core, which would be a close match to our own proper time, i.e. the same Dilation (divergence) from proper time, without adjusting for our own region of gravitationally bound mechanics. This would be true, unless we first were able to establish a consistent figure from the most proper time, to our own, to then apply said figure to all of our observations outside of our local galaxy.