Dark matter Definition and 919 Threads

Does the path of light from distant galaxies curve according to with or without dark matter and energy?

Space is filled with gravitons moving in every direction. These gravitons push masses together and cause "attraction". When gravitons approach a spiral galaxy parallel to its plane, they get pushed together and concentrated by the magnetic field lines of the galaxy. As they double their...

Greetings, When I was still in college, a professor commented that it was possible that gravity was not a force. He based this on the observation that gravity didn’t seem to have opposite charges. The force of electricity has positive and negative. Gravity does not seem to have such...

I have read that the Dark-Energy may be a consequence of Pressure from outside of the Universe. The presence of a spin zero field (higgs-field) seems to make this idea really interesting. Negative pressure was postulated by Poincaire, Dirac. Accordingt to the author, negative...

This paper: http://www.edpsciences.org/papers/aa/pdf/press-releases/aa0959.pdf ...press release: http://www.eso.org/outreach/press-rel/pr-2004/pr-08-04.html suggests that the kinematic heating (statistical dispersion of velocities in the perpendicular plane to the galactic plane) of...

i don't understand how dark matter acts upon the rotation of a galaxy. galaxy rotation doesn't work the same way that solar system rotation does in that it's not a simple gradient of further planets rotate slower, right? nor is it further planets rotate faster, like a vinyl record...i take it...

Dark matter?? What's that?

http://physicsweb.org/article/news/8/2/4 6 February 2004 Many astronomers believe that the universe is dominated by cold 'dark matter' and 'dark energy' - a view that has been confirmed by recent measurements on the cosmic background radiation. Now, however, a group of astrophysicists in...

I am not sure what forum category this should go in, but since Cahill's paper (see abstract and link below) claims to be the first evidence for discrete space, which of course supports LQG, this may be the appropriate location. I searched the Physics Forum for Cahill and got zero hits. His...

SDSS observations, supported by Subaru and Keck, confirmed that a massive cluster of galaxies is the gravitational lens for a quadruple-quasar image, the widest pair being separated by >14" (arc seconds). In addition, "[d]iscovering one such wide gravitational lens out of over 30,000 SDSS...

What I've heard is that galaxies are spinning weirdly. They are spinning on the outer regions too fast. Also that the velocity of the outer stuff is 10 times greater than the gravitational force of our galaxy itself. So we say that there is this dark matter that we can't see at any wave lengths...

After recently seeing Brian Greene's "Elegant Universe," I was struck by an idea - maybe not an original idea, but an idea nonetheless. If gravity is a weak force because it is not stuck to the "brane" of this universe, then gravity from our universe can influence others and vice versa from...

Scientific American, March 2003 - "dark Matter" The Search for Dark Matter" Scientific American March, 2003 Page 52: "For 70 years, astronomers have steadily gathered circumstantial evidence for the existence of dark matter, and nearly everyone accepts that it is real. But...

I went to a cosmology seminar recently. It was mostly for fun, but if you complete a take home exam you get a tiny bit of college credit for it. Things were going along fine until I ran across the last two questions: How was Dark Matter just discovered and when did this happen? What...

Knotty Jets, the Tell Tales for Early Dark Matter and Spiral Galaxy formation. It is proposed that the new paradigm for Black Holes with a nuclear particle content, see http://home.planet.nl/~vuyk0022/ , lead to a 2 stage semi-cold Black Hole evaporating Big Bang see...

Joe Silk, who is world class, is one of the co-authors of this preprint http://arxiv.org/astro-ph/0309686 "MeV Dark Matter: Has It Been Detected?" the paper is dated 1 October of this year. A sharp line of gammaray from near Milkyway center has been observed at 511 keV energy. A...

Greetings ! I wonder if we really need to pursue just the dark matter direction to explain why galaxies turn the way they do and the whole cosmology part about the form of Universal space-time. Has there been an attempt to explain the motion of galaxies by adding another Universal law...

People have "invented" it out of a need to explain large scale motions in the Universe, but is it really there? Might there be other explanations? Here's an interesting page about it. http://www.astro.ucla.edu/~agm/darkmtr.html You can get more by putting "dark matter" into Google or...

So, it seems that Dark Matter now takes up most of space. What does that mean? What exactly is Dark Matter and why did we miss it before? How will change astronomy? Educate me on this please.:smile: Thanks.