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Dark Matter - Is Its Existence Grossly Exaggerated?

04/05/2006 06:08PM

Dark Matter - Is Its Existence Grossly Exaggerated?

Many Astrophysicists believe that most of the matter in the universe is dark -- that is it cannot be detected from the light which it emits (or fails to emit). By some accounts, 90% of the universe is made up of this mystereious Dark Matter. Its presence is inferred indirectly from the motions of astronomical objects - specifically stars, galaxies, galaxy clusters, and galaxy superclusters. However, there may be another possible explanation. Instead of the existence of unseen material, maybe our understanding of Gravity is incorrect. If that is the case, then current calculations for the amount of Dark Matter in the Universe are grossly exaggerated. New research has revealed that a simple "fine-tuning" of Einstein's theory of gravity could solve the Dark Matter mystery that has baffled Astrophysicists for three-quarters of a century.


I like this new theory.<br><br>If they plug it into the calculations of Voyager 1's path, can it explain it's unexplainable position?<br><br>I also wonder if we can use Voyager 1's position to fine tune the formula and get it to fit the rest of the universe...<br><br>Duane Deal
Duane:<br><br>You bring up a very good point.<br><br>What you are referring to is he "Pioneer Anomaly" (although I believe the Voyager spacecraft has also experienced a similar effect as it drifts out of the Solar System).<br><br>For those who don't know about it, the Pioneer 10 spacecraft was launched in 1972. Miraculously, NASA has been able to track it all this time and after 34 years it appears to be about a quarter of a million or so miles off track from its expected location in the outer Solar System.<br><br>What is causing it? Nobody knows, but an improved theory of gravity could help explain it. Hopefully scientists will get a chance to test this new gravitational theory against data from the Pioneer 10. We'll just have to wait and see. <br><br>Interestingly, NASA lost touch with the sister spacecraft Pioneer 11 in 1995. Up to that point it was also off track and experiencing a very similar deviation. And it exited the Solar System on the opposite side. <br><br>Guy Pirro<br><br>

  • hrkant [Harlan Kant]
  • 04/08/2006 08:06AM
First let me say I'm just an observational amateur astronomer that gets a kick out of the whole hobby, and part of it for me is reading science books for non-scientists. That said, I've read a lot of books and thought a lot about the current state of cosmology theory. I recommend to all a book by Barrow entitled "Constants of Nature" (2002) in which he explores in more detail some of these ideas. I believe we are just beginning to get a glimpse at the answers and that most of the accepted thinking about the formation and age of our universe will be undergoing radical changes for quite a while. So much of our theory seems built on such a web of flimsy assumptions that we may indeed be missing large pieces of the puzzle. I would like to be around a hundred years from now and see what the physicists are coming up with. Remember, just before Einstein's relativity theory, many physicists expressed the feeling that everything important had already been discovered and only fine tiuning of the theories remained. Do we really grasp the dual nature of matter and quantum mechanics in any meaningful way? Do all our current theories really do much more than fit our anthropic observations? I have always been highly suspicious of dark matter. There really is a whole new world to discover, and perhaps always will be. Our very existence limits our observational abilities and understanding of the universe. So keep an open mind, and sign me up for the time machine list. I wonder what the physicists and mathematical adept among us really think of this idea of gravity varying over large spaces, because it seems we basically ignore it over very small spaces, so why not. And what is time? If anyone knows, more power to them. Sorry about these ramblings, but I remain in my everlasting quandary. Beam me up Scotty, and kudos to Astromart for providing such a resource to the amateur community.
Many persons, even sometimes great scientists, get 'fixed ideas' that color everything that comes after, as they go on a crusade to prove their point, not stopping along the way to see whether or not maybe context can modify or vary the values they hold to be absolute. This happens in linguistics all the time. Order versus chaos. We have plenty of loud voices shouting their lungs out championing one or the other. The rest of us are left scratching our collective heads. 'Tastes Great!'; 'Less Filling!'<br>The real world often throws multiple variables at you simultaneously.<br><br>What is thought of as initial, or unitary, also colors theory. Think of electrical charge. Even today, notation reflects the idea that the electron retains a unit charge, calling quark charges multiples of a third. That's crazy! And nobody has a clue about mass assignment- Higgs not withstanding. Sure there are trends- quarks in the same series are heavier than the leptons, within those sets the higher charged unit heavier than the lower. Tauon units higher than muon higher than electron in series. Except for the up and down quark, where the values are inverted. How do you explain that?<br><br>Some theoreticians feel compelled to 'explain away' any loose ends which jeopardize their neat little models of reality. Unfortunately, as in the case of Ptolemy, you can to to town with epicycles or what-have-you to stay one step ahead of the naysayers, but then simplicity goes down the toilet.<br><br>As for universal expansion I'll say this again- this is only one possible interpretation. The other extreme is that matter is everywhere shrinking- yesterday's matter if bigger would have produced longer wavelengths. Or it could be a mixture of both spacetime expansion or massenergy shrinkage. How could you ever tell, in a world without absolute reference standards for comparison? Maybe if the notion is true then it has something to do with enthalpy and entropy in the universe generally? Current matter would produce higher frequency radiation than in the past, eventually leading to what? This might jibe with the 'Big Rip' idea of accelerating expansion.<br><br>All this would explain why life seems to grow more hectic by the day, too!<br><br>Jess Tauber

It's hard to revive an idea that has been disproved. Tired light has been disproved, (look-up: time dilation of high redshift supernova light curves).<br><br>However, when you have current theories that don't explain the current situation, it's time to "think different".<br><br>I agree that when you plop in mathematical equations just because they fit, you run the risk of making up your own theories that fit the situation. However, through such a process so many theories have been proven correct. How do you think Einstein came up with so many correct theories? Look at ? (Einstein's cosmological constant). He called it his biggest mistake and yet today we are going back to it and plugging it in to explain the observable universe.<br><br>Duane

OK after reading all these answers sounds like to me everyone who posted really needs a good healthy dose of College Chemistry and College Physics and I'm not talking about the High School variety but the courses you would take after you had mastered Calc 1 and II I have a question for you Herbert why are the masses on the periodic table related to the Carbon 12 nucleus you know the element Carbon 6 protons that assigns the element its atomic number and then the addition of 6 neutrons added to give us the atomic weight.<br><br>As far as electrical current is concerned you measure from a reference potential so if your ground is negative you treat the circuit as if electrons flow from Negative to positive. It only when you dealing with semiconductors ie transistors do you reverse the explanation which makes it easier to understand what is going on inside the crystal lattice. Its still electrons that are moving holes don't move..<br><br>As far as tired light is concerned, light has no mass that is why light can travel at the speed of light if light did have mass it would not travel at the speed of light. Light travel can be altered by a strong gravitational field because space is curved near a large mass and light will follow the shortest path or geodesic as some like to say. So I ask you this how in the blue blazes can light get tired. <br><br>Clear Skies<br>Dwight L Bogan