Galaxy without any dark matter baffles astronomers

Discussion in 'Science' started by cerberus, Mar 29, 2018.

  1. cerberus

    cerberus Well-Known Member Past Donor

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  2. iamanonman

    iamanonman Well-Known Member

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    Who knows. If they end up being particles then we might one day being able to tame and utilize them like we did with the electron, photon, and other matter particles. But, yeah, if it just brings us one step closer to figuring out the ultimate fate of the universe then it's probably more like chewing gum for the brain. I still find it interesting either way.
     
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  3. drluggit

    drluggit Well-Known Member

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    Perhaps what really matters is the acknowledgment of just how much we, as a species, don't know, or understand. I think that provides an excellent plane though for future work.
     
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  4. waltky

    waltky Well-Known Member

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    Granny says, "Dat's right - an' ya ain't gonna see any either - `cause it's too dark to see...
    [​IMG]
    Astronomers find galaxy without any dark matter
    Fri, Mar 30, 2018 - Stupefied astronomers on Wednesday unveiled the first and only known galaxy without dark matter, the invisible and poorly understood substance thought to make up a quarter of the universe.
     
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  5. WillReadmore

    WillReadmore Well-Known Member

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    Our model of physics isn't good enough to explain our universe.
    https://home.cern/about/physics/standard-model

    I don't believe it's rational to stop at a point where our model of physics just doesn't answer the questions of physics that are so easy for us to ask today.

    Einstein trashed much of existing physics with his relativity theory - a revolution that had major ramifications for humans. And, it came at a time when physics had been cruising along without many seeing physics as being particularly interesting.

    We could well be headed toward a similar revelation.

    Would such a next step be as impactful as Einstein's?

    My wild guess is that it is pretty hard to judge that, coming from our current situation. But, it's totally insane to simply stop learning.
     
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  6. cerberus

    cerberus Well-Known Member Past Donor

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    (thinks) :roll: There's no hope for him, and yet he seems such a nice guy. I'll just have to write him off as one of my failures!
     
  7. DoctorWho

    DoctorWho Well-Known Member

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    You have had resounding success along those
    lines ! !
     
  8. cerberus

    cerberus Well-Known Member Past Donor

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    With all due modesty, I suspect a few readers of my thoughtful and thought-provoking posts have gone away to think about it all. :cool: Mebbe you should, too, because you're letting them fool you. :nod:
     
  9. fmw

    fmw Well-Known Member

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    Hanging your hat on a substance that cannot be detected or measured just tells me that cosmologists have some serious holes in their knowledge.
     
  10. WillReadmore

    WillReadmore Well-Known Member

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    I'm assuming it is dark matter that you are talking about here.

    So, I'll point out that dark matter can be measured through gravitational effects on matter that can be directly detected.
     
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  11. fmw

    fmw Well-Known Member

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    No. It isn't measured and certainly not detected. It is calculated because the calculation fills a hole in our knowledge. It is a mathematical construct designed to provide an explanation for something we don't understand. In other words things work as we think they do as long as we include dark matter in the equation. But things probably work in some other way that we don't yet understand. That's fine. Good science will likely work it all out in the future.
     
  12. WillReadmore

    WillReadmore Well-Known Member

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    By "measured" I mean that the amount of this factor can be measured by calculating the "hole" (as you put it) when observing the behavior of all directly detected matter.

    So, if our sun were somehow invisible, one could "measure" its mass by evaluating the behavior of the planets.
     
  13. fmw

    fmw Well-Known Member

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    But planets do not orbit dark matter. There is no interaction between dark matter and visible matter. Dark matter isn't matter. It is mathematics. It may exist or it may not. I'm on the may not side of the equation because it cannot be detected. It is a popular concept with cosmologists because it explains the way they think things work. If things work in some other manner, then it doesn't have to exist.
     
  14. WillReadmore

    WillReadmore Well-Known Member

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    There IS gravitational interaction, and that is measurable.

    I don't know why dark matter hasn't been found to aggregate by gravity into dense objects that would be able to maintain nearby satellites.

    That's an interesting point.

    You are more than free to propose some other explanation of how things work. But, I would suggest it is highly unlikely that the measurements made by astrophysicists have systematic error so large as to make dark matter merely a mistake.
     
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  15. fmw

    fmw Well-Known Member

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    I don't know how things work. Astronomical science doesn't either. It is fun that they are working on it. That is how we learn how things work.
     
  16. One Mind

    One Mind Well-Known Member Past Donor

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    If this is true, how is that different from the religious true believers believing in something which cannot be seen nor measured? The religious folks catch hell from the people who try to use science to negate God, which cannot be seen nor measured...yet if science does it, then it is fine? What am I missing here?
     
  17. fmw

    fmw Well-Known Member

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    Who said it is fine? Certainly not I. I just said I think science is wrong about dark matter. It is an opinion. I said nothing at all about religion. I'll leave that to you.
     
  18. WillReadmore

    WillReadmore Well-Known Member

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    You went farther than that. You said, "I don't know how things work. Astronomical science doesn't either." Earlier you said dark matter couldn't be measured.

    I'm ok with you doubting that dark matter exists - though it's a minority opinion.

    But, I'm not as impressed by your sweeping rejection of astrophysics.
     
  19. DoctorWho

    DoctorWho Well-Known Member

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    You can't hang your hat on a memory.

    Cosmetologists too,
    Sally Struthers is a disaster zone !
     
    Last edited: Apr 27, 2018
  20. eathen lord

    eathen lord Active Member

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  21. HereWeGoAgain

    HereWeGoAgain Banned

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    DM causes physical effects that CAN be measured.
     
  22. One Mind

    One Mind Well-Known Member Past Donor

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    What if something unknown was causing those effects that can be measured? For lest we forget, DM had to be conjured up, or otherwise so many equations and understanding were at risk. And so to keep from changing that, DM was conjured up, in order to make the equations valid.

    Just because an effect is measurable, does not in anyway confirm that dark matter, which cannot be seen, an invisible thing, actually exists. Now, it might require a totally new discovery, a change in paradigm, in order to get away from this concept of DM, and that is all that it is, given it cannot be discerned to exist using any instrument, that would show it to us.

    I think one of the problems of science is that acts as if everything is already known when it comes to the universe and our very limited understanding of it. Who was the UK physicist who said long ago ,that the field of physics was complete and all that was left was for us to get a better understanding of it? This was before QM of course. And so, classical newtonian physics was in his opinion, as a scientist, was everything and all that we would ever need to know.

    Nothing lies outside of it. And this seems to be the attitude we see today with some of those in science. Except of course they must now include QM and QP. Yet at one time, we thought we knew most of all of what our reality is.

    When it was discovered, using physics, that there was not enough matter in the universe, or a galaxy to explain what was being observed in regards to galaxies, we came up with the idea of DM. For more matter was needed in order for the formation of galaxies to be coherent, and possible, and yet we could not see any such additional matter which was needed.

    And so, it must be there, and it is invisible! And we believe that only matter residing in space, and it distorting space/time, will give us gravity, whether we can actually see it or not. But what if that isn't actually a fact? But just an assumption?

    What if in the future we discover that we really didn't actually understand gravity at all? That DM does not exist, except as a concept that allows the equations to work out? And that the gravity needed in order to form and keep intact a galaxy, does not come from some invisible DM?

    Of course this would bring another paradigm shift within science, as we continue the work in trying to understand this universe and how it actually works. Which has happened in science before, and will more than likely happen again.

    So, a belief in DM is nothing more than that, a belief. Based upon nothing more than an assumption, but granted, it is a decent assumption and coherent with current physics. And we surely didn't want to say that the physics, the equations, the understanding to date is wrong. So, much easier to just create a new concept, of matter that is invisible to current instruments, and then say it just has to exist. Because if not, then our understanding and equations has flaws. And is just wrong.
     
  23. HereWeGoAgain

    HereWeGoAgain Banned

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    There is a force consistent with a unknown mass acting according to the known laws of physics, that we call Dark Matter.

    That isn't conjecture. It is a fact. Scientists are currently trying to study and explain what we observe to be true.

    If there was a force wildly inconsistent with the laws of physics, it might suggest a flaw in physics. But that isn't the case. We can observe how dark matter effects many bodies and see that it is consistent with the known laws.
     
    Last edited: May 12, 2018
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