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Dark Matter

  1. Nov 26, 2009 #1
    Ok,so im a bit of a noob so go easy on me!
    i was having a chat recently with my uncle (whos an astro physicist here in the UK) and although he didnt really give me the time of day becuause hes a busy guy,he said that my idea wasnt too far fetched but to come back to him when its got a bit more substance.
    so im asking you guys to help me get the substance,because i plainly just dont know enough yet to formulate the idea properly myself,or see any glaring holes in it.

    its a vague idea (and im under no illusion that its correct,i would just like to explore the idea)

    Ok so i was thinking about the background foam of the vacuum (i know worded badly) and thought about time dialation as well. if time is going slower closer to a gravitating body (or group of bodies) then do the particles that come in and out of existence in the vacuum last slightly longer when closer to the mass of the galaxy, esentially what im asking is could the dark matter be accounted for with the mass of all those virtual particles. or at least from our inertial frame do the virtual particles seem last longer? kinda like renormalisation but for galaxies? but the extra mass shown by the flat roation curve is due to virtual particles contributing their mass for a longer time (or the same time,but slower from out perspective)?

    i know its a badly worded questions but if you can descipher what im saying please show me where ive gone wrong or what the problems are with this idea!
    Last edited: Nov 26, 2009
  2. jcsd
  3. Nov 26, 2009 #2


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    It's a funny idea, not bad.
    I see two main issues, aside from how virtual particles contribute to gravity:
    1 - the particles would not only last longer, they would also be created more rarely. Their density should be the same
    2 - even if (1) were irrelevant, the density variations would be much less than the overall density. With such a density, the universe would have recollapsed long ago.
  4. Nov 26, 2009 #3
    why would they be created more rarely? (is it because if time was going slower,the spacing between each particle being created would also be larger? sort of balancing itself out)

    so if the virtual particles were contributing as much mass as would be required to explain the phenomenon,it would lead to a closed universe?
  5. Nov 26, 2009 #4


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    Yes, kind of seeing the same thing in slowmo.
    Terminally closed by now.
  6. Nov 26, 2009 #5
    Do virtual particles contribute at all then,they must make up some part of the matter that contributes to Omega?
  7. Nov 27, 2009 #6
    If you took virtual particles into account, omega would be roughly speaking 10^120, which is quickly ruled out by experiment. :-)
  8. Nov 27, 2009 #7
    Side note, if you're really interested about this stuff you should consider formal education. I'm in a similar situation as you. I have all these great ideas and theories but since I lack the proper education, I have more questions than anything. If you think about it, much of the physics we know today took lifetimes to accomplish. We have the capability to learn so many lifetimes worth of information, it allows us to advance at an accelerated rate. Modern physics is so complex that if you really want to make a contribution you have to go to grad school.
  9. Nov 27, 2009 #8
    I'm going to start studying physics when the next academic year starts,sept 2010,hopefully,for the moment though im watching as many lectures as i can find to get my head around the conceptual stuff,and most of my spare time im putting into maths so that i hit the ground running when i start the course.

    I am getting a little frustrated with the maths though,the lack of a clear starting point to lead me into the physics is my main problem,comprehension isnt going badly though,ive bought a few books to help,but considering im not in full time education,time is a bit thin on the ground and progress can be slow (although the more i work,the more im finding i get AHA moments and it all starts to fall into place)

    are you going to be studying it too then?
  10. Nov 27, 2009 #9
    Yes. I'm undergrad right now, but I plan on going to grad school for physics too. For some reason, education is structured in such a way that math and physics aren't really taught hand in hand. I'm learning all this seemingly pointless calculus but I've realized that it's all building towards the more advanced applicable ideas. I'm trying to learn as much as I can on the side, but I'm a little overwhelmed by the sheer amount of information.
  11. Nov 28, 2009 #10
    quite,there is an astonishing amount of information to tackle!have you seen the TTC lectures?they arent the best but they do cover a huge array of topics,which is nice to just dip into every now and again.berkeleys Physics 10 and astro 10 lectures are out there on the net aswell if you havnt seen them yet. as are the MIT lectures,but they are heavily based in maths,whereas the others are mostly conceptual. im kinda surprised that as an undergraduate you get the same amount of time to learn all the information as someone in a much simpler course, 1095 days isnt much time to get a firm grip on the subject as far as im concerned,maybe im just a little slow though.

    one thing im a little concerned with is the huge array of other topics that i have to cover in the same time,it seems that taking up physics requires you to essential do a physics,maths,computation,programming,philosophy aswell as have a flair for teaching and communication,among other things,im not sure how to fit it all in! any tips?
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