dark matter

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newtonian

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borman - HI!<br /><br />I'm glad you are still posting at SDC - your posts always are a challenge to understand and respond to - and very enlightening also.<br /><br />And I lack the time to respond properly until Friday at the earliest.<br /><br />However, it sounds so simple (i.e. your idea) - how could we miss it!<br /><br />Like icing on a jet!<br /><br />So much simpler than my way outside the box suggestion that there are actually gravity bonds which hold objects (probes, etc.) in a set course, but which when broken allow attractive forces to add influence previously stopped by the gravitational bonds.<br /><br />BTW - my mind still gets boggled by the acceleration causing slowing!
 
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the_masked_squiggy

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Hey, you wrote those articles yourself!<br /><br />Good way to explain theories without taking up boatloads of space though.
 
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harmonicaman

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Please don't mix "Dark Matter" and "Dark Energy" theories in the same topic; it gives me a really bad headache and aggravates my ulcer! <br /><br />These are two totally unrelated concepts; only the names happen to bear an unfortunate and regrettable similarity... <img src="/images/icons/mad.gif" /><br /><br />In my opinion; the Dark Energy crowd usurped the "Dark" title for their own theory because it sounded sexy (and the word "Darth" would have been a bit 'over the top'). The "Dark Matter" geeks came up with it first; they win!<br /><br />That being said; "Dark Energy" theory is no longer considered the wacko pseudo-scientific psychobabble it was a few years ago where discussions of its relevance were relegated to the wall space above the urinals; but it still has a <i>very long way to go </i> before becoming accepted as mainstream scientific thought.<br /><br />"Dark Matter" theory, OTOH, is simply another way of saying; <i>"You know, there's gots to be lots of stuff in the universe that we just can't see!"</i><b> - Well, DUH!</b>
 
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Saiph

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right, the debate on dark matter isn't whether or not it exists but:<br /><br />How much of it is there?<br /><br />Where is it, and how is it distributed?<br /><br />And what is it made of?<br /><br />The last one gets a lot of attention. Some is undeniably regular matter that just isn't putting out light (planets, non-hydrogen components of cold gas clouds, etc). Unfortunately our best estimates of this material can't account for all that is required to match up with other observations.<br /><br />I.e. our estimates of how much dust exists in a galaxy cannot explain the orbits of the stars. If we put enough dust in there to make up the difference, we have an extreme amount (and would disagree with other, often more reliable observations).<br /><br />All our estimates for regular matter are constrained to certain ranges. Unfortunately, they don't all total up to be enough, and so we have "unknown" dark matter over which people debate it's composition (MACHOS, WIMPS, etc). <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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jatslo

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(9.109 3826(16) x 10 <sup>-31</sup> kg; 1/1836.15267261(85) amu; 0.510998918(44) MeV/c <sup>2</sup>) <sup>1-Bazillion</sup>
 
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Saiph

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problem with that: the electrical charge will quickly attract other matter, and the biggest problem is dark matter within galaxies, where the level of isolation isn't even hypothetically large enough. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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hayagreeva

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Description: BOOK ANNOUNCEMENT:SEARCH BEYOND DARK MATTER-Vision series-I IMPORTANT NOTES VISION DEVELOPMENT SERIES ARE IN PHASES COVERING “COSMOS YOGA SERIES- I ~10^3 LY - Tamasoma Jyothirgamyam ..BEYOND DARK MATTER BY VIDYARDHI NANDURI TXU 1-282-571 JUNE 2005 Copy rights USA The first stage of the THREE-TIER UNIVERSE is explained in this part of the Vision series-I that helps to identify SEARCH BEYOND DARK MATTER. In Philosophy, this mode of search is known as TAMASOMA JYOTHIRGAMAYA. In simplistic terminology, it is LEAD KINDLY LIGHT over DARK MATTER in order that more LIGHT or high-intense mode LIGHT destroys the DARKNESS OF THE MINDS attached to either MATERIAL MODE or as STREAMLINED THINKING. As dark mode MATTER is segregated from the LIGHT MODE KNOWLEDGE ROUTE , the higher DIMENSIONAL VISION to THE UNIVERSE must become SELF-EVIDENT. The thinking of the MINDS may be in Dark-Matter or Matter as it exists in the UNIVERSE. The material mode is a DOWN-LINK THROUGH NATURE while the VISION DEVELOPMENT should help SEARCH BEYOND DARK MATTER with a DIRECTION for LINKS towards DYNAMIC FUNCTION OF THE UNIVERSE A few related questions arise: TO SCIENTISTS- SEARCH, INTERPRET,REFLECT DATA and see ALIGNMENT TO PHILOSOPHERS: SURRENDER, BALANCE RECEPTION, DIVINE GRACE for PERCEPTION. Alignment of BODY, MIND, CONSCIOUSNESS are desirable qualifying principles. UNITY: The Scientific essence becomes SELF-EVIDENT to decipher KNOWLEDGE through COSMOLOGY AND VEDAS. The SCIENCE OF PHILOSOPHY AND PHILOSOPHY OF SCIENCE may find many merging routes through VISION DEVELOPMENT series. SEARCH ROUTES: Search BEYOND CHAOS, Search beyond DARK Matter, Search beyond BLACK_HOLE Psychology and Search beyond Mind-set modes The COSMOS YOGA searches for ORDERLINESS as NATURE PROVIDES LINKS and COSMOS DATA provides SIGNATURES. MAY COSMIC DIVINE LORD OF SEVEN HILLS GUIDE THE INTELLECT AND CONSCIOUSNESS FOR WELFARE OF HUMANITY This search is part of COSMOLOGY FOR WORLD PEACE NOTES: Pages 77 Drawings and
 
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dragon04

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Interesting article. However, something just occurred to me while reading it. As I am no physicist, I can only make a crude attempt at explaining my notion in an understandable manner.<br /><br />Imagine two black holes separated by distance <i><font color="yellow">n</font>/i>.<br /><br />In 3 dimesnsions, their gravity wells are depicted as curved cones, whose cross sections diminish rather rapidly towards the singularity.<br /><br />So when we see two black holes "merging", <i><font color="yellow">n</font>/i> reduces to zero at the event horizons, but the singularities are ostensibly some non zero <i><font color="yellow">n</font>/i> apart.<br /><br />Now, let's further jump forward to the completion of the merger of the event horizon "regions". One cone "mouth" and two discrete singularities.<br /><br />Do the singularities continue to merge or do we reach some kind of equilibrium or "focal point" where the system stabilizes?<br /><br />Or conversely, do the singularities merge first and draw the surface regions together from the "bottom up" like zipping up your trousers?<br /><br />Are BH's always oriented the same? Meaning what happens if two BH's have gravity wells that run in opposing diections?<br /><br />I'm "out there" on this, but is there anyone who could refute my hypotheses in terms I'd understand? I'm all up for a learning experience this afternnon. <img src="/images/icons/smile.gif" /> <br /><br /></i></i></i> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>
 
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vandivx

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<blockquote><font class="small">In reply to:</font><hr /><p>ViperGTSR3g: and how are you so sure that dark matter exists?<p><hr /></p></p></blockquote> well, the phenomena does exist, it is established fact. When it is understood though, it might turn up to be something different from matter that is causing the observed effects that are now ascribed to dark matter. But untill it is, the name dark matter is just as fine as any other even if it might turn up just funny gravitation. <br /><br />----------------------------------<br />I am itching to say something different though. I just started reading these forums and I find it weird in that this confirmed ranter can go on posting here, in capitals none the less, and even bump up half a year old threads which later might not matter here much as topics in science are good to discuss today as they were yesterday or year ago, still this one was bumped by unrelated rant.<br /><br />I have to say this is not the best forum I've ever posted on. People's signatures (or what you call it here) flow with text and many times I read signature not quite realizing right away, can't people at least put line above their signatures? That should really be handled by forum software which btw seems to be pretty poor, which brings me to still other complaint. <br /><br />Most people don't know how to quote or don't care and it makes for confusing reading. How come this forum doesn't have Quote button. Normally when it does and you use it, it even appends name of poster to the quote automatically. <br /><br />I mean, this is science forum and the talk here is about discoveries and all that and it is discussed on such poor outdated forum software. Weird. What next, some BB from early 1980s to discuss the latest cry in computer software and future of internet, how perverse LOL<br /><br />Don't take offense though, perhaps this is best forum there is among free forums (no idea if this one is free, just thinking it must be), anyway I don't know realities behind the <div class="Discussion_UserSignature"> </div>
 
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bonzelite

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<font color="yellow">well, the phenomena does exist, it is established fact.</font><br />yeah, right, charlie. the only established fact is that they don't know jack diddly bop, sunshine. <br /><font color="yellow">When it is understood though, it might turn up to be something different from matter that is causing the observed effects that are now ascribed to dark matter.</font><br />ok you have a moment of reason here...<br /><font color="yellow">But untill it is, the name dark matter is just as fine as any other even if it might turn up just funny gravitation. </font><br />....only to accept it and all that it implies as a PC term --as it assumes that "they're all right" about flat rotational velocities observed in galaxies. the minute you accept "dark matter" as a term, even as a stand-in for something quite unknown, you automatically accept it and it's basis for theory. and it's total crap. how about rethinking the entire premise behind the mechanics of the cosmos than to instead invite more and more garbage theories into more theories based on unknowns? ---theories that are sacred cows yet fraught with contradictions and ad hoc measures. <br /><br />pardon me while i throw up. <br /><br />you should go and think about what you're saying in the corner over there and come out a little later. no dinner for you. <br />
 
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vandivx

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<blockquote><font class="small">In reply to:</font><hr /><p>....only to accept it [dark matter term] and all that it implies as a PC term --as it assumes that "they're all right" about flat rotational velocities observed in galaxies. the minute you accept "dark matter" as a term, even as a stand-in for something quite unknown, you automatically accept it and it's basis for theory. and it's total crap. how about rethinking the entire premise behind the mechanics of the cosmos than to instead invite more and more garbage theories into more theories based on unknowns? ---theories that are sacred cows yet fraught with contradictions and ad hoc measures.<p><hr /></p></p></blockquote><br />well, why would you be 'rethinking the entire premise behind the mechanics of the cosmos' if apparently you don't accept experimental evidence that something is out of order out there to beging with (the evidence of those flat rotation curves and intergalactic motions etc)<br /><br />but perhaps I misunderstood what you tried to say in between the put downs you interlaced it with<br /><br />from how the establishment is getting to you I'd guess you have it all solved already but your theories are not getting acknowledment that you believe they deserve<br /><br />I know perhaps more than you do how 'inapropriate name' can deviously mislead entire field of scientists due to false premise being established (smuggled in) by it but it leaves me unphazed, I don't take it on my shoulders to enlighten the scientific community as whole and I am quite content to look from side at the decades of wasted efforts of multitude of scientists and millions mis-spent on red herring chase <br /><br />all that huge waste just works to make your 'truth' regarding the matter at hand all that sweeter if and when it gets recognized, finally recognized I mean ... because I believe truth will get recognized eventually, you just have to hope you live long enough in some cases LOL<br /><br />vanDivX <div class="Discussion_UserSignature"> </div>
 
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vipergtsr3g

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My take on dark matter is it doesnt exist at all. It is only believed to exist because we haven't taken into account that the farther back in time you go, the faster everything was moving if the big bang theory is correct...<br />think of an explosion. at first everything is flying out in all directions. however the fprce of gravity and air friction will slow all the particles down and make them eventually land on the ground. this is not much different in space, everything is tugging at each other with gravity slowing each other down, however, since the universe is so big now, by the time light reaches us from say an object 50 million light years from us, the object will appear to be travelling away form us really fast, but if we viewed it today it would be travelling much more slowly then the light we see would hint at. same thing when viewing something even farther away, like at the edge of our observable universe. lets say an object about 15.5 billion light years away looks like its travelling away from us at near the speed of light, if we could see it today it would be substantially slower since as time went by, it was being pulled back slower and slower by the stuff behind it. basically if you understood my explanation, the farther the things are, the farther back in time we are seeing them, which we all know is true, so that we will be seeing them closer and closer to the point of the big bang, meaning we will be seeing them closer and closer to their original speed after getting expelled from the big bang.<br /><br />I also hope that the discution here in this thread will be reasonabley spam free so that I will be the size of earth instead of the measely proton I am now.
 
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doubletruncation

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<font color="yellow">My take on dark matter is it doesnt exist at all...</font><br /><br />What you say regarding gravity tending to slow the expansion of the universe down is true. Matter does decelarate the universe, and this is an effect that is definitely built into the equations that model the expansion of the universe. You can, in fact, attempt to measure the average mass density of the universe by measuring the distance-redshift relation and seeing how the slope of that relation changes over redshift.<br /><br />Now there is evidence for "dark matter" that is largely independent of the expansion of the universe. One of the conceptually easiest ways to see why people talk about "dark matter" are galactic rotation curves. (See for example http://www-astronomy.mps.ohio-state.edu/~pogge/Ast162/Unit6/dark.html.) When you look at a galaxy you can measure the doppler shift of spectral features along the galaxy, at different distances from the center. The doppler shift tells you the average velocity towards or away from us of the material at that position in the galaxy. In a spiral galaxy the stars will tend to orbit the center of the galaxy, so in fact on one side of the galaxy the light will be blueshifted relative to the average radial velocity while on the other side the light will be redshifted. For a circular orbit, the orbital speed at radius R will be given by v ~ sqrt(G*M/R), where M is the mass enclosed within radius R. So, by measuring the speed v at different radial positions R you can get the total gravitational mass of the galaxy as a function of distance from the center. It's not quite as simple as that, but conceptually that's basically how it works. Now if you plot mass as a function of R you'll see that it falls off very slowly relative to the light, and the mass that you infer for the galaxy is many times larger than what people can accou <div class="Discussion_UserSignature"> </div>
 
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alokmohan

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Brown dwarfs are candidae for dark matter.There are many undetected brown dwarfs.Plane mos throws new light.
 
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jessez13

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In my opinion there are only two real positions to take on this issue. <br /><br />1 there is a large amount of exotic dark matter in the universe or <br /><br />2 We do not understand gravity on a universal scale or under extreme conditions. <br /><br />I am of the second camp who have been working on the problem. <br /><br />Even though I agree with the basics behind GR theory most people do not question that when GR theory is applied they use the classical<br />gravitational potential developed by Newton.<br /><br />There are several possible gravitional potentials that do not require exotic dark energy or even an event horizon when plugged into GR<br /><br />They also do not significantly change any predictions in the area where GR has been proven correct
 
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hayagreeva

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REF:The "braneworld universe" has five dimensions -- four spatial dimensions plus time -- compared with the four dimensions -- three spatial, plus time -- laid out in the General Theory of Relativity.<br /><br />COMMENTS: MILKY WAY GALAXY has more than Five dimensions- Scientists seem to have ignored reality.<br />See my projections in Books- SRISTI,STITHI, LAYA <br />and one needs to search beyond DARK MATTER.
 
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enigma10

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0.o<br /><br /> I'm so not going to ask what side of the green fields you're squatting on. <div class="Discussion_UserSignature"> <em>"<font color="#333399">An organism at war with itself is a doomed organism." - Carl Sagan</font></em> </div>
 
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tex_1224

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What role does Dark-matter have in the gravity of a galaxy? how much matter can we acount for in a galaxy, and how much of it is considered Dark-matter?<br /><br />Do the laws of physics change when considering dark matter?<br /><br />Do the particles of Dark-matter vibrate faster or slower than regular matter?<br /><br />this is off the topic, but I like to think of black holes as a sort of shredder. Like the ones the tree service guys have in the big orange truck. lol
 
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enigma10

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Outside of the global warming subject, i think the dark energy/matter discussions are the next largest scattered/displaced threads and would love to see columns for both subjects for only those subjects<br /><br /> <div class="Discussion_UserSignature"> <em>"<font color="#333399">An organism at war with itself is a doomed organism." - Carl Sagan</font></em> </div>
 
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