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Max the Magnificent
In the book Reinventing Gravity (see the column above) the author points out ...
bogdanbmcc
The fact that an equation cranks out good predictions in the area we can test ...
Is this a map of dark matter or the "fools gold" equivalent?
Clive Maxfield
5/11/2012 6:09 PM EDT
Like Winnie the Pooh, I am a bear of simple brain, and many things confuse and confound me. One such topic is that of dark matter.
As I've mentioned before (see my Review of Reinventing Gravity by John Moffat), when Sir Isaac Newton presented his Theory of Universal Gravitation in 1687, everyone quickly came to the conclusion that "this was it" – a theory that truly described the way in which the universe worked.
After a while, however, they came to realize that the planet Mercury wasn't orbiting the Sun in quite the way it should. Since the folks of the time absolutely believed in the concept of Newtonian gravity, they looked for an explanation that would fit into this "world view." The solution they came up with was that there must be an undiscovered planet (which they called Vulcan) in orbit between the Sun and Mercury. Based on this proposal, many folks devoted huge amounts of effort and ingenuity trying to find this planet... that we now know does not exist.
It was more than two hundred years later, in 1916, that Albert Einstein published his theory of General Relativity, whose description of space-time curvature sorted out the problem of Mercury and appeared to provide all of the answers (gravity-wise).
For close to 100 years, General Relativity has been accepted by the majority of folks as fully describing gravity. But once again there's a problem. Astronomers have discovered that the stars at the edges of rotating galaxies are travelling much faster than they should be... so fast that they should fly off into space... but they don't.
In order to address this, astronomers and physicists came up with the concept of Dark Matter. The idea in a nutshell is that Dark Matter is something we can't "see" or "taste" or anything like that... except through its gravitational interactions. Am I the only one who finds this conclusion to be a tad dubious?
Thus it was that I was somewhat irked by a recent column in Discover Magazine, which was titled Largest Map of Dark Matter Across the Cosmos. The associated image (see below) came from the NASA Website (Click Here to see the original posting of this image and associated text).
A snippet from the article in Discover is as follows:
Later on, talking about a catalog of gravitational lensing that has been compiled over the last five years, the article goes on to say:
Now call me "Mr. Fuddy Duddy" is you wish, but I don’t find this argument ("Wherever there was a dark matter peak, there was a massive cluster of galaxies") to be particularly convincing. The thing is that gravitational lensing is also associated with the real mass constituting the galaxies.
Proponents of dark matter will counter that the dark matter is "wrapped around" galaxies. For myself, having read a lot of "stuff" from a lot of sources, I'm much more inclined to think that the answer lies in another direction, which is that the Einsteinian theory of gravity is incomplete, not the least that – thus far – we haven't managed to tie gravity into the other fundamental forces that manifest themselves at the quantum level.
I don’t know why, but I have a "gut feeling" that we are on the verge of making some really big discoveries that will dramatically change the way in which we view the universe. I cannot wait to see whatever developments come our way in the next 10 or 20 years. Watch this space...
If you found this article to be amusing and/or of interest, visit Programmable Logic Designline where – in addition to my blogs on all sorts of "stuff" (also check out my Max's Cool Beans blog) – you will find the latest and greatest design, technology, product, and news articles with regard to programmable logic devices of every flavor and size (FPGAs, CPLDs, CSSPs, PSoCs...).
Also, you can obtain a highlights update delivered directly to your inbox by signing up for my weekly newsletter – just Click Here to request this newsletter using the Manage Newsletters tab (if you aren't already a member you'll be asked to register, but it's free and painless so don't let that stop you [grin]).
As I've mentioned before (see my Review of Reinventing Gravity by John Moffat), when Sir Isaac Newton presented his Theory of Universal Gravitation in 1687, everyone quickly came to the conclusion that "this was it" – a theory that truly described the way in which the universe worked.
After a while, however, they came to realize that the planet Mercury wasn't orbiting the Sun in quite the way it should. Since the folks of the time absolutely believed in the concept of Newtonian gravity, they looked for an explanation that would fit into this "world view." The solution they came up with was that there must be an undiscovered planet (which they called Vulcan) in orbit between the Sun and Mercury. Based on this proposal, many folks devoted huge amounts of effort and ingenuity trying to find this planet... that we now know does not exist.
It was more than two hundred years later, in 1916, that Albert Einstein published his theory of General Relativity, whose description of space-time curvature sorted out the problem of Mercury and appeared to provide all of the answers (gravity-wise).
For close to 100 years, General Relativity has been accepted by the majority of folks as fully describing gravity. But once again there's a problem. Astronomers have discovered that the stars at the edges of rotating galaxies are travelling much faster than they should be... so fast that they should fly off into space... but they don't.
In order to address this, astronomers and physicists came up with the concept of Dark Matter. The idea in a nutshell is that Dark Matter is something we can't "see" or "taste" or anything like that... except through its gravitational interactions. Am I the only one who finds this conclusion to be a tad dubious?
Thus it was that I was somewhat irked by a recent column in Discover Magazine, which was titled Largest Map of Dark Matter Across the Cosmos. The associated image (see below) came from the NASA Website (Click Here to see the original posting of this image and associated text).
A snippet from the article in Discover is as follows:
Astronomers believe dark matter makes up a quarter of the universe, yet it does not absorb or emit light, and nobody has detected a particle of it. Fortunately, dark matter does reveal itself in a subtle way: As light approaches a clump of the mysterious stuff, it bends around it in a phenomenon known as gravitational lensing. The more massive the clump, the more the light bends.
Later on, talking about a catalog of gravitational lensing that has been compiled over the last five years, the article goes on to say:
Their map, which covers 100 times as much sky as previous surveys, reveals giant heaps of dark matter enveloping galaxies. "Whenever there was a dark matter peak, there was a massive cluster of galaxies." (The quote [I added the bold highlight] was from astrophysicist Catherine Heymans who is one of the principles on the project.)
Now call me "Mr. Fuddy Duddy" is you wish, but I don’t find this argument ("Wherever there was a dark matter peak, there was a massive cluster of galaxies") to be particularly convincing. The thing is that gravitational lensing is also associated with the real mass constituting the galaxies.
Proponents of dark matter will counter that the dark matter is "wrapped around" galaxies. For myself, having read a lot of "stuff" from a lot of sources, I'm much more inclined to think that the answer lies in another direction, which is that the Einsteinian theory of gravity is incomplete, not the least that – thus far – we haven't managed to tie gravity into the other fundamental forces that manifest themselves at the quantum level.
I don’t know why, but I have a "gut feeling" that we are on the verge of making some really big discoveries that will dramatically change the way in which we view the universe. I cannot wait to see whatever developments come our way in the next 10 or 20 years. Watch this space...
If you found this article to be amusing and/or of interest, visit Programmable Logic Designline where – in addition to my blogs on all sorts of "stuff" (also check out my Max's Cool Beans blog) – you will find the latest and greatest design, technology, product, and news articles with regard to programmable logic devices of every flavor and size (FPGAs, CPLDs, CSSPs, PSoCs...).
Also, you can obtain a highlights update delivered directly to your inbox by signing up for my weekly newsletter – just Click Here to request this newsletter using the Manage Newsletters tab (if you aren't already a member you'll be asked to register, but it's free and painless so don't let that stop you [grin]).
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Duane Benson
5/11/2012 6:38 PM EDT
Back in my college chemistry class, I became pretty good a dry labbing experiments. That had the dual benefits of allowing me to get the work turned in even if I didn't get into the lab that week, and of giving me a way to check my work when I did get into the lab.
Sometimes the experiment and the dry labbed value didn't quite match up. If that error was too large, the solution was to add in a fudge factor at an appropriate point in the calculations. I suspect that may essentially be what dark matter really is.
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drward
5/11/2012 6:48 PM EDT
Reminds me of the speculation surrounding the existence of an "ether" that would permeate space and was the medium of transmission for electromagnetic waves. It was abandoned when relativity came along but now the concept is being rethought...is Dark Matter and/or Dark Energy the new ether?
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Max the Magnificent
5/11/2012 6:51 PM EDT
There is so much interesting stuff coming out at the moment. Different ways of looking at space and time and gravity. There was an article a couple of months ago about this sort of thing, speculating that gravity might be affecting the red-shifts of far away galaxies and that time may "flow" differently in different parts of the universe, to the extent that -- essentially -- some parts of the universe may be "older "than others ... sort of thing...
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seaEE
5/11/2012 10:52 PM EDT
Who knows? Maybe we will be able to travel back in time and live with the dinosaurs like they did in the 1970's tv show, Land of the Lost.
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Max the Magnificent
5/12/2012 11:06 AM EDT
I don't think I ever saw this -- I'm not sure if it played in the UK (does anyone from the UK remember it?)
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David Brown
5/15/2012 5:21 AM EDT
There are plenty of possible explanations of dark matter. In particular, astronomers keep finding /real/ dark "things" out in space, such as brown dwarfs and lonely planets. These sorts of things are very hard to see, and have very little effect on their own. But in combination they could well provide the "missing" mass that can be detected by gravitational lensing but cannot be accounted for by visible stars.
A much more "ethereal" concept is dark energy. This is not really much more than Einstein's original "fudge factor" in relativity. Does it exist, or is it just a case of the current theory (relativity) being a little inaccurate, just like Newtonian gravity before it? Even more subtly - is there actually a difference between "real" dark energy and a fudge factor in an equation?
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Max the Magnificent
5/15/2012 11:38 AM EDT
There was an amazing article in the March 2012 issue of Discover magazine about the work of Scientist Julian Barbour and Physicist David Wiltshire.
The bottom line is that if they are right, cosmologists may expect supernovas to be closer than they appear, creating the ILLUSION that the expansion of the universe is speeding up...
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Bellhop
5/15/2012 3:56 PM EDT
Dr. Michio Kaku once said that you can solve these problems simply by adding dimensions. He says that eleven dimensions is what it takes to unify it all. Kaku is a co-inventor of string theory and is looking for the one equation that explains it all.
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Max the Magnificent
5/15/2012 3:59 PM EDT
I was met Dr Kaku a couple of years ago. As a gift I gave him a copy of my book "Bebop to the Boolean Boogie"
Now I come to think about it, I did warn him that I would be "asking questions later" ... I wonder if he's read it yet?
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Mike.Nemeth_#1
5/18/2012 2:24 PM EDT
drward: No, Dark Matter and Dark Energy is the new Phlogiston!
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Max the Magnificent
5/18/2012 2:27 PM EDT
I wouldn't say that to a physicist -- you might get your fingers burnt :-)
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jimwilliams57
5/18/2012 2:42 PM EDT
It all comes down to that fact that we don't know everything. Theories are just that, theories. If a theory can't be proven, then it's still just a theory. And until it is proven, I'll continue to think of it as just a theory.
I've always been skeptical of dark matter, string theory, and other attempts to make the universe fit the current equations. And that isn't likely to change within my lifetime.
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Stephen.Sywak
5/18/2012 2:47 PM EDT
max, you're not alone. I really dislike the ideas of "Dark Matter" and "Dark Energy." They feel like fudge factors made manifest. Or, worse: the place where God is allowed to creep back into what has, so far, been a wonderfully, purely, materialstic Universe.
One of the things I've been trying to get an answer to is this: do astrophysicists allow for the fact that when they look deeper and deeper into the universe, finding that wonderful, changing red shift of objects moving away from us at different speeds--faster speeds the further away they are, IIRC--do they allow for the fact that not only is that data coming from a far distant source, but a far OLDER source?
So, regardless of which direction you're looking out at, if you see light that is 14 billion years old, with some huge red shift in its spectrum (vs. the expected gaps, etc., that make the red shift mean what it means), of COURSE there's going to be a high velocity associated with it. It's as close to the BIG BANG as you can get. And if the universe is SLOWING, wouldn't you expect the early speeds to be high, and the current speeds to be lower?
Maybe there ARE answers to this question out there (links, please? Pretty please?) and I'm just too slow to realize it....
Steve Sywak
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przemek
5/18/2012 2:55 PM EDT
As a resident physicist, you gotta be careful knocking established theories like that. First, dark matter isn't even that strange, compared to dark energy, which according to its own theory comprises 90% of the mass of the Universe, and is so significant that it changes the entire geometry and dynamics of the Universe, by causing its expansion.
Secondly, those theories have been quite extensively peer reviewed. They may not be perfect, but they are the best explanation of the known facts. If the facts were explainable better by the actions of little green men, the Little Green Men theory would be the one to beat---it doesn't make sense to argue over philosophical merit if the math works out! People still argue about the philosophical underlying of quantum mechanics but the math is solid and we crank out practical results day in and day out.
Bottom line is, the only criterion is the theory's predictive powers. Ether theory didn't fail because ether was strange, but because it predicted a doppler shift in the speed of light, which failed to appear in the Michelson-Morley experiment.
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Sparky_Watt
5/18/2012 5:54 PM EDT
On the ether thing, I disagree. A quasi-newtonian interpretation of ether predicted that the interference fringes in the Michelson-Morley would move. The experiment therefore disproved that understanding of ether. However, Einstein did not provide an alternative! He simply showed that, if you use light to measure the universe (which we do, even the lengths of our rulers are established by electromagnetic phenomena), that the Michelson-Morley experiment would fail, because of the Lorenz-Fitzgerald contraction. I think you will find that if you re-interpret ether in that context that it is no longer contradictory. It got dropped not because it was invalid, but because it no longer contributed anything. In an Einsteinean context, Ether can't be measured. That doesn't mean it doesn't exist, just that it is operationally meaningless. A flowing medium for Electromagnetic forces may still be there. We just can't detect it because we are making our measurements using it. Like trying to measure the velocity of water using that same water as a reference. You always come up with zero. That doesn't mean the water isn't moving, it just isn't moving with respect to itself.
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Isleguard1
5/18/2012 3:21 PM EDT
I'm not an astrophysicist (and I don't play one on TV)..but... I have been following string theory for a while and this is my opinion on dark matter.
It seems to me that the multidimensional universes that vibrate (credit: Dr Kaku on TV) and when they touch you get an interaction between them (in short, the big bang). Now if you think of frequency/math analysis, when two frequencies interact, you get the sum and the difference between them. Think about these multidimensional universes as gigantic polynomials that interact.
When polynomials interact, the differences provide the first 4 dimension’s which we normally call length, width, height and time.
In my humble opinion, the upper level dimensions (5+) should be counted as the dark matter. This would account for possibly some mass that doesn't interact well with the lower 4 dimensions. Remember that some equations have missing terms in them (ax+bx^2+0x^3+dx^4... or 0ax+bx^2+cx^3...) which could also be the case.
As I said, this is my opinion only, I have no proof and about the only thing that I could back this up with is by comparing it to frequency analysis.
So this is how I look at the universe and try to understand it with my small mind.
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Frank Eory
5/18/2012 6:43 PM EDT
If it turns out that dark matter is "fool's gold" then so must dark energy be. If both are really just components of a fudge factor needed to make an incorrect cosmological theory fit our observations, then cosmology is in for an enormous upheaval when dark matter/energy is finally debunked.
The universe is said to be 74% dark energy and 22% dark matter, leaving only 4% for the matter & energy we actually can observe. 96% is one heck of a fudge factor!
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Max the Magnificent
5/19/2012 10:53 AM EDT
Obviously I am not an expert -- but I have a feeling that things are going to get stirred up very soon (in the next 10 years) re this topic ... I can;t wait to see how it all turns out...
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minorwork
5/18/2012 9:28 PM EDT
What instrument can look at a battery or capacitor and determine if it is charged or not charged? Mass should be only slightly different but at a distance in space how do you tell what potential energy is there? Dark energy.
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WKetel
5/19/2012 7:40 PM EDT
If one has selected the career of being an astronomer, and being well paid for it, one must deliver interesting reports from time to time, otherwise those large paychecks may cease. So discover a huge pile of almost undetectable stuff at a distance so great that nobody will ever be able to prove or disprove it within your lifetime. And if you are wrong, well, it seemed reasonable at the time. Just think what we might develop if all of these great minds did not waste every day investigating things that are too far away to matter.
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bogdanbmcc
5/25/2012 6:01 PM EDT
The fact that an equation cranks out good predictions in the area we can test does not mean that it will be doing it correctly elsewhere (err .. that is in the areas we cannot test at the moment ..). I do embedded software so I use extrapolated and interpolated equations a lot, they are good enough but I know better that they are not the "real" thing :-0
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Max the Magnificent
5/26/2012 11:41 AM EDT
In the book Reinventing Gravity (see the column above) the author points out that if there is Dark Matter around spiral galaxies then you might expect to find it around other shaped galaxies also ... but there are some that would behave differently if Dark Matter were present... so the fact that they behave the way they do says Dark Matter isn't present, which says ... well ... I think we will discover what it says real soon...
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