Having hard time finding Dark matter

Discussion in 'Physics & Math' started by timojin, Mar 25, 2017.

  1. Xelasnave.1947 Valued Senior Member

    Messages:
    3,293
    I think I read that so I dont claim it as my term.
    I do think we could replace "dark" with "unknown" which may make critics happy.
    Alex
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Michael 345 Valued Senior Member

    Messages:
    3,674
    As are my 3 ideas

    Please Register or Log in to view the hidden image!

     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. The God Valued Senior Member

    Messages:
    3,546
    No, DM is not a fudge factor, since it is observation based. If DM is not there then we have to re visit our theories. We have to insert something which can account for observations in a similar way as DM does.
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Michael 345 Valued Senior Member

    Messages:
    3,674
    Shakespeare?

    A rose?

    Please Register or Log in to view the hidden image!



    Please Register or Log in to view the hidden image!

     
  8. Q-reeus Valued Senior Member

    Messages:
    2,605
    How would a less descriptive 'unknown matter' be preferable to 'dark matter' which, assuming it is matter, exactly fits it's non-interacting, except through gravity, behaviour?
     
  9. Xelasnave.1947 Valued Senior Member

    Messages:
    3,293
    First it is preferrable because I thought of calling it such however if you need more....
    I dont really care but I dont find "dark" offerring the implication of non interacting.
    How about "non-interacting unknown matter" or "nium".
    Or "non-interacting, except by gravity unknown matter" giving us a new word "niebgum".
    Alex
     
  10. timojin Valued Senior Member

    Messages:
    3,252

    By looking on a earth gravity map one should see on high elevation there should less gravitational force and at sea level should be highest gravity force if DM have some to do with gravity ? but it is not so , if anything is the oposite
     
  11. Q-reeus Valued Senior Member

    Messages:
    2,605
    Niebgum. Reads more like a new brand of chewing gum. Fortified with extract from the exotic Nieb plant? Hope the flavour is just as refreshing as spearmint.

    Please Register or Log in to view the hidden image!

     
  12. Q-reeus Valued Senior Member

    Messages:
    2,605
    Have you made any attempt to do a quantitative calculation? Checked the assumed average density of DM on a galactic scale, and figured if that extremely low density would have any perceptible influence on a terrestrial scale? I think if it were in the right ball-park to show up, searches would have long ago been undertaken and any effect published to make headline news.
     
  13. Michael 345 Valued Senior Member

    Messages:
    3,674
    How about

    "Something which makes up most of our Universe which we can't see except it seems to act by possible gravity so we suspect it should be matter MATTER"

    To long?

    Calling Humpty Dumpty

    Its Dark Matter

    Please Register or Log in to view the hidden image!

     
  14. DaveC426913 Valued Senior Member

    Messages:
    7,227
    A century ago, we saw dark blotches on photo-sensitive film that we couldn't explain. How could the film be affected right through solid opaque materials?

    X-rays had not been discovered. We did not have the technology to isolate the phenomenon we were seeing.

    Because some scientists had the discipline to follow the observations instead of their preconceptions, we eventually built detectors - and X-rays were dragged out of mystery and into science.

    Our technology and understanding of cosmological phenomena is still quite young.
     
    Last edited: Apr 2, 2017
  15. Q-reeus Valued Senior Member

    Messages:
    2,605
  16. timojin Valued Senior Member

    Messages:
    3,252
    Let me say if the DM would be a subatomic particle it should be dispersed through the galaxy because is such a large percentage of total matter. If the DM would be laying on our earth in layers at the sea level the density should be the highest but according to the gravity map Indian ocean shows the lowest gravity on the earth. So how can we equate this to the so called lensing effect. ?
     
    Last edited: Apr 2, 2017
  17. Q-reeus Valued Senior Member

    Messages:
    2,605
    So you were not aware that the 'dark' part of dark matter implies any constituent particles are extremely low interacting with ordinary matter or radiation. All those underground detectors are based on just that assumption - DM passes right through the earth as though it wasn't even there. Except for vary rare interactions with an atomic nucleus that triggers a decay event. So far no independently corroborated evidence of even that. As an assumed low interacting gas it has a strong tendency to stay dispersed, and the balance between such pressure and gravity plays out on a large scale.

    The upshot is DM is fapp a very dilute 'gas' that clumps only on the scale of galaxies and galaxy clusters/super clusters. Hence the lensing you refer to involves DM distributions on those scales. Certainly not on a planet sized or even solar system scale. Of course if DM is not even matter but something else, it will change the details but not the evidence for gravitational clumping on those large scales.
     
  18. DaveC426913 Valued Senior Member

    Messages:
    7,227
    You really need to understand the Dark Matter does not interact with normal matter in that way. It does not pile up on the ground.

    Ah. Q-reeus covered that.
     
  19. timojin Valued Senior Member

    Messages:
    3,252
    So it is magic, and we ( science ) does not know what it is . So why use such term ?
     
  20. DaveC426913 Valued Senior Member

    Messages:
    7,227
    I have no idea why you would say that.

    So, you see choices as binary in science? We fully understand something OR it's magic?
     
  21. DaveC426913 Valued Senior Member

    Messages:
    7,227
    Tim, don't you think it requires just a tad more knowledge about some thing before passing judgment?

    You have not read up on DM at all (as evidenced by your description of how it interacts), yet you're already comfortable deciding that it's nonsense. Do you not acknowledge that your conclusion may be just a skooch premature?
     
  22. timojin Valued Senior Member

    Messages:
    3,252
    Sorry , I am wrong in my judgment.
     
    spidergoat likes this.
  23. martillo Registered Senior Member

    Messages:
    877
    Even if the alternative idea implies Einstein's theory being flawed? I don't think so.
    Agreeing with karenmasker, better to not waste time to just being called a crackpot. Better to just wait for better times...
     
    Last edited: Apr 5, 2017

Share This Page