DailyDirt: Where Has All The Matter Gone?

from the urls-we-dig-up dept

There are vast amounts of stuff that no one knows anything about. Everything in the universe that we can see -- that reflects light or glows on it own because it's hot -- only amounts to about 5% of the known mass of the universe. So... what's going on with the other 95% of "stuff" that's out there? Maybe there are exotic particles we haven't discovered yet that are everywhere, but we just don't know it. Physicists call this stuff "dark matter" and "dark energy" -- and there could be a whole "dark sector" of dark matter doing things that we just can't see. But we're getting some hints for some of the stuff we can't see by observing and measuring the outcomes of rare astronomical events -- and by creating simulations of what possible undiscovered particles might do to the formation of galaxies and other distant space objects. Here are just a few projects that might explain how the universe works someday. After you've finished checking out those links, take a look at our Daily Deals for cool gadgets and other awesome stuff.

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  • identicon
    Lawrence D’Oliveiro, 23 Mar 2016 @ 5:27pm

    Religionists Seeking Vindication From Science

    Some believers in the Genesis accounts* of creation try to point to the Big Bang theory as some kind of backing for their belief.

    The trouble is, the theory is having real trouble producing just one Big Bang. The cosmic background radiation is too smooth, given the time available for temperature differences to propagate across space. To fix this, theoreticians have come up with “cosmic inflation”, which kicked in and massively expanded the size of the Universe, thereby smoothing it out.

    But having turned on the inflation field, you then need to invent another mechanism to turn it off. Otherwise, if it continues to act, you get, not one Big Bang, but an infinite series of Bangs, continually spawning off an infinite number of Universes. Trouble is, there is no experimental evidence for the existence of such a mechanism.

    Another possibility is that the Universe looks smooth because the Bangs are cyclic: after some period of time, the expansion reverses, everything comes together in a Big Crunch, after which the Universe is reborn in a new Big Bang.

    If you want to be religious about it, obvious parallels can be drawn with Hindu/Buddhist ideas of reincarnation. Because it isn’t just Christians who get to have the fun...

    *That’s “accounts”, as in two different accounts, that don’t actually agree with one another.

    reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 23 Mar 2016 @ 7:50pm

    lowly layman question. do we think we can see the entire universe, dark matter excepted? do we think we know what's past the last you are leaving the universe sign?

    reply to this | link to this | view in chronology ]

    • icon
      Bri (profile), 23 Mar 2016 @ 9:57pm

      Re:

      Nope! Astronomer here! The extent to what we can see is called the observable universe. That is a distance of 46 billion lightyears away. This has to do with the fact that our universe is expanding, so if a particle emits light, how far could it travel before the universe is expanding so fast light can never reach a further point? We assume that everything past the horizon is the same as here, but we have no way of knowing that since our understanding of the universe is limited by the speed of light. We can't get any information past that horizon. It could be different, but our understanding of fundamental physics tells us that location in the universe doesn't make you special, so there is no reason for it to be different.

      This question is giving me flash backs to my preliminary exam when this question was asked and we had to calculate a bunch of distances based on the age of the universe. Don't remember if I did too well on that question...

      reply to this | link to this | view in chronology ]

      • icon
        JoeCool (profile), 24 Mar 2016 @ 1:41pm

        Re: Re:

        A little high on that value. The current record (according to NASA) is 13.2 billion ly, and if it pans out, an observation that is being validated would push that to 13.7 billion ly. According to NASA, the current estimate of the age of the universe is 13.73 billion years with an uncertainty of 120 million years.

        reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 23 Mar 2016 @ 8:18pm

    Theory and Practice

    Based on prevalent theory, certain groups have come up with the idea that the matter seen is only a small part of the total mass. The rest is essentially non-observable. All tests to date have not given credence to the idea of dark matter or dark energy. These are theoretical additions to force the prevalent theories into agreement with observation.

    Cosmic background radiation levels are actually not very smooth at all. From the expected calculated amount (for which there have been a number of different values since the various theories have been promulgated), there is a large percentage variation as measured across the sky. Even though these variations are actually quite small absolutely, they vary significantly from the various smoothness predictions from theory.

    The base assumption that the universe is a charge neutral environment and hence gravity is the overriding base control force is physically not testable in any area of the universe other than in close proximity to our planet.

    Even the measurement of solar winds indicates that charge variation occurs within our own solar system. How these charge flows outwork in the larger galactic and intergalactic environment is a question that won't be answered as long as the basic assumption above is unquestioned.

    Science is not about being politically correct but about actually investigating the environment and doing/developing repeatable tests and experiments. Waiting on extremely rare events to test a hypothesis, leaves open the position that, if those events do not occur often enough for repeatability, the model being developed is more than likely unsupportable.

    The current Big Bang models being used leave more questions unanswered than answered. From an engineering perspective, the development of the results that are from Einstein's General and Special Relativity models are also obtainable from classical models. Even the effect of electron tunnelling is explainable without recourse to quantum mechanics, it is explainable using classical electromagnetic models.

    There is so much to learn about our universe, that closing our minds to alternate viable models just because they may oppose our strongly held beliefs of how the universe is, is an indictment of our abilities.

    reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 23 Mar 2016 @ 10:16pm

    What cracks me up

    One group - there's too much matter, because galaxies are spinning faster than they should
    Second group - there's not enough matter, because universe expansion is accelerating

    reply to this | link to this | view in chronology ]

    • identicon
      Lawrence D’Oliveiro, 23 Mar 2016 @ 10:47pm

      Re: there's not enough matter, because universe expansion is accelerating

      A mere insufficiency of mass cannot cause the expansion to accelerate.

      Gravity is always attractive, remember.

      reply to this | link to this | view in chronology ]

      • identicon
        Anonymous Coward, 23 Mar 2016 @ 11:58pm

        Re: Re: there's not enough matter, because universe expansion is accelerating

        Gravity is always attractive, remember.
        But why?

        I have seen one somewhat reasonable answer to this specific question and it involves gravity being an effect of the dipole nature found within atoms. The model even gives a resultant magnitude of about the same magnitude. Yet, when asked about this model, the only response from a theoretical physicist was that it was a load of rubbish. No attendant explanation as to why, just out of hand dismissal. Go figure. The paper itself was, as far as I know, peer reviewed.

        reply to this | link to this | view in chronology ]

      • identicon
        Anonymous Coward, 24 Mar 2016 @ 1:03am

        Re: Re: there's not enough matter, because universe expansion is accelerating

        Gravity is always attractive, remember.
        But why?

        I have seen one somewhat reasonable answer to this specific question and it involves gravity being an effect of the dipole nature found within atoms. The model even gives a resultant magnitude of about the same magnitude. Yet, when asked about this model, the only response from a theoretical physicist was that it was a load of rubbish. No attendant explanation as to why, just out of hand dismissal. Go figure. The paper itself was, as far as I know, peer reviewed. I find such actions amongst those who are supposed to be logical, systematic investigators as being incompatible with their field of endeavour.

        reply to this | link to this | view in chronology ]

      • identicon
        Anonymous Coward, 24 Mar 2016 @ 6:38am

        Re: Re: there's not enough matter, because universe expansion is accelerating

        Is gravity linear over vast distances?

        Does gravity continue to "obey" the inverse square law no matter what the distance between objects?

        reply to this | link to this | view in chronology ]

        • icon
          John Fenderson (profile), 24 Mar 2016 @ 6:57am

          Re: Re: Re: there's not enough matter, because universe expansion is accelerating

          Gravity does not appear to be a "force" like light, radio waves, etc. Rather, it appears to be an effect of geometry. As such it does not "transmit" over distance at all.

          (Although debate continues over whether there is a particle associated with gravity, like there is with electromagnetism, our current observations seem to support the Einsteinian view of gravity.)

          reply to this | link to this | view in chronology ]

          • identicon
            Anonymous Coward, 24 Mar 2016 @ 12:24pm

            Re: Re: Re: Re: there's not enough matter, because universe expansion is accelerating

            Gravity does conform to the inverse square law over solar system type distances, whether it applies over galactic, and larger, distances is still being debated.

            Does not matter what word you use to label it, the gravitational effect over limited distances is well understood and modeled. Evidence of this is our ability to navigate the solar system. Recent observations have added to speculation about the existence of gravity waves, very interesting stuff and many implications.

            reply to this | link to this | view in chronology ]

          • identicon
            Anonymous Coward, 24 Mar 2016 @ 4:44pm

            Re: Re: Re: Re: there's not enough matter, because universe expansion is accelerating

            Gravity does not appear to be a "force" like light, radio waves, etc. Rather, it appears to be an effect of geometry. As such it does not "transmit" over distance at all.
            What does it means to be "force" like? A definition of "force" is
            an influence on a body or system, producing or tending to produce a change in movement or in shape or other effects.
            gravity is all of this. Where it appears to differ from some other forces is that we have observed only attractive versions of it.

            Being "an effect of geometry" is no more an explanation than any other mathematical formulation. That is simply a model that is proposed to describe its working.

            Too often, people use mathematics as the sine qua non for what is, instead of mathematics being a tool for investigation. I know of a number of "geometrical" models for some physical attributes of the universe that "work" but are not the reason for the attribute. It is a simplifying methodology to get some workable results.

            The Einstein view of gravity is a non-classical view and for what it is worth, has been used with some success. However, there are views that are based on classical mechanics that give the same general results. All this means is that the various models are approximately in agreement with experimental results. This approximate agreement does not in any way confirm the "truth" of any of these models. These models are, in effect, methods for trying to understand and for trying to "get things done".

            When science diverts into "truth", it becomes metaphysical and religious in form. It becomes the very thing that many find objectionable about metaphysics and religion.

            Science is a very useful tool when looking at the "how", the "when" and the "where". It is not so useful when looking for the "why".

            The "why" looks into the "cause" of causes, the beginnings are always problematic because they are non-repeatable events.

            reply to this | link to this | view in chronology ]

            • identicon
              Lawrence D’Oliveiro, 24 Mar 2016 @ 5:39pm

              Re: When science diverts into "truth", it becomes metaphysical and religious in form.

              Is that the “truth”?

              reply to this | link to this | view in chronology ]

              • identicon
                Anonymous Coward, 24 Mar 2016 @ 7:41pm

                Re: Re: When science diverts into "truth", it becomes metaphysical and religious in form.

                Ahh, a metaphysical question.

                reply to this | link to this | view in chronology ]

              • identicon
                Anonymous Coward, 24 Mar 2016 @ 8:41pm

                Re: Re: When science diverts into "truth", it becomes metaphysical and religious in form.

                Sarcasm aside, I find your lack of understanding of science and its limits to be an interesting statement on the quality of the education we give our people.

                Let me ask you a quite simple question that you should be able to answer with complete certainty. What "truths" has science proven?

                reply to this | link to this | view in chronology ]

                • identicon
                  Lawrence D’Oliveiro, 24 Mar 2016 @ 8:42pm

                  Re: Sarcasm aside

                  No sarcasm. It was a simple question. Can’t you answer it?

                  reply to this | link to this | view in chronology ]

                  • identicon
                    Anonymous Coward, 25 Mar 2016 @ 5:02am

                    Re: Re: Sarcasm aside

                    I have to laugh at your attempt of avoiding the bullet. It is you who declared
                    Science is all about taking the models to the limits and beyond. How else do you find out what the truth is?
                    so my question was to you to demonstrate this. When you can so answer in any meaningful discussion, then you may gain some kudos, otherwise all you demonstrate is that you are ignorant of the topic at hand.

                    See my response to your other comment below.

                    reply to this | link to this | view in chronology ]

                    • identicon
                      Anonymous Coward, 25 Mar 2016 @ 5:46am

                      Re: Re: Re: Sarcasm aside

                      I thought the pompous ass approach to scientific discussion was abandoned long ago ... must have been wishful thinking.

                      Science does not attempt to declare truth, it attempts to understand and model the world around us - thus providing a way to predict what will happen under given conditions.

                      If you are in pursuit of "the truth" then possibly science is not your best choice for a career.

                      reply to this | link to this | view in chronology ]

                      • identicon
                        Lawrence D’Oliveiro, 25 Mar 2016 @ 1:43pm

                        Re: pompous ass approach

                        Friendly tip: when you start resorting to personal attacks, that’s an admission you’ve run out of rational things to say.

                        reply to this | link to this | view in chronology ]

                        • identicon
                          Anonymous Coward, 25 Mar 2016 @ 6:34pm

                          Re: Re: pompous ass approach

                          Oh wow - thanks for the heads up.

                          btw, the other guy was a pompous ass ... you - I'm not sure about yet.

                          reply to this | link to this | view in chronology ]

                        • identicon
                          Anonymous Coward, 25 Mar 2016 @ 11:16pm

                          Re: Re: pompous ass approach

                          Friendly tip, heckling is also an admission that you have nothing rational to say. Particularly, when you are given opportunity to clarify your position in a logical, rational way.

                          reply to this | link to this | view in chronology ]

                      • identicon
                        Anonymous Coward, 25 Mar 2016 @ 11:13pm

                        Re: Re: Re: Re: Sarcasm aside

                        It is interesting that when Ld'O is asked a question, he, either cannot answer or simply tries to deflect by witless heckling.

                        Science does not attempt to declare truth, it attempts to understand and model the world around us - thus providing a way to predict what will happen under given conditions.
                        This is the very point that L d'O disagrees with. He has communicated that science is about finding the "truth". He does not seem to understand the point above.
                        If you are in pursuit of "the truth" then possibly science is not your best choice for a career.
                        One of the points I have attempted (and up to this point obviously failed at) to help him understand.

                        reply to this | link to this | view in chronology ]

  • identicon
    star lord, 24 Mar 2016 @ 6:24am

    no crunch and why

    ok take water about 5% put 95 % oil n a bag, shake it up, now take sad bag and hold it up and empty it....the universe expands , and something is pulling us all to the edges of the universe...well its what lies out sde the universe folks , cant prove t ever but thats whats going on....NOW you could even take away the oil and still happens thus n a weird way i dont need "dark matter" to make this work.

    think of a dimension as a bag around a bag. around another bag and in the outer bag s all the oil/water....pink prick it and gravity will at first look to fill the void and then pull to the edges....

    have fun im sure someone can get more techy on it but ts now looking more and more like prolly im right

    reply to this | link to this | view in chronology ]

  • identicon
    mpc755, 24 Mar 2016 @ 1:55pm

    Dark matter is displaced by matter

    Dark matter is not a clump of stuff that travels with the matter. Dark matter fills the space unoccupied by particles of matter and is displaced by the particles of matter which exist in it and move through it. Dark matter strongly interacts with matter. Dark matter is displaced by matter.

    [0903.3802] The Milky Way's dark matter halo appears to be lopsided

    "the emerging picture of the dark matter halo of the Milky Way is dominantly lopsided in nature."

    The Milky Way's halo is not a clump of dark matter traveling along with the Milky Way. The Milky Way's halo is lopsided due to the matter in the Milky Way moving through and displacing the dark matter, analogous to a submarine moving through and displacing the water.

    What physicists mistake for the density of the dark matter is actually the state of displacement of the dark matter. Physicists think they are determining the density of the dark matter by how much it and the matter curve spacetime. What they fail to realize is the state of displacement of the dark matter is curved spacetime.

    reply to this | link to this | view in chronology ]

    • identicon
      Anonymous Coward, 24 Mar 2016 @ 5:07pm

      Re: Dark matter is displaced by matter

      Assumption 1. Dark matter exists. It is a "theoretical" artifice required for specific models of the universe to match observable effects in the universe. Since it is a "theoretical" artifice, there is no requirement for the universe to fulfil the wishes of those proposing the model.

      Assumption 2. Model is reality. Since all models are simplifications to explain reality, there is no requirement for the universe to fulfil the wishes of those proposing the model.

      Engineering teaches you the limits of models and not to take any model beyond those limits. Theoretical physicists don't seem to have learned that lesson and often appear to take their mathematical models into the realms of fancy without stopping to think that maybe their mathematical models are no longer applicable. See the bun fights between the various groups of string and non-string theorists as a modern example.

      They have gotten so caught up in their mathematical theory and the correctness of their mathematics that they have forgotten why they came up with their mathematical models in the first place.

      They need to have some chill pills, slow down, have a beer, eats some pretzels and play on the swing with their children, nephews and nieces. They need to smell the roses and cow dung that fertilises them. They need to take time out and see reality for what it is.

      reply to this | link to this | view in chronology ]

      • identicon
        Lawrence D’Oliveiro, 24 Mar 2016 @ 5:40pm

        Re: Engineering teaches you the limits of models and not to take any model beyond those limits.

        Science is all about taking the models to the limits and beyond. How else do you find out what the truth is?

        reply to this | link to this | view in chronology ]

        • identicon
          Anonymous Coward, 24 Mar 2016 @ 5:57pm

          Re: Re: Engineering teaches you the limits of models and not to take any model beyond those limits.

          This is true.

          A potential problem with this can occur when one becomes so convinced of the theory's efficacy that contradictory data is ignored or written off as inconsequential. Huge arguments can even erupt.

          Confirmation bias is alive and well, even scientists trained to be impartial fall victim.

          reply to this | link to this | view in chronology ]

        • identicon
          Anonymous Coward, 24 Mar 2016 @ 8:19pm

          Re: Re: Engineering teaches you the limits of models and not to take any model beyond those limits.

          Science is all about taking the models to the limits and beyond. How else do you find out what the truth is?
          Scientism lives.

          Science is nothing of the sort. Science is about developing testable models (of which theories are one kind of model) that give insight into the universe about us. The models so developed can and should give additional predictions for which we can test. It deals with experimental facts (repeatability is one requirement). A model is not proven "true", at most, it can be proven "false".

          If a model fails to give any testable predictions then we must ask the question, is it a valid science model? If the model gives predictions that are found to not quite match the experimental evidence, do we tweak the model or do we look for another model that gives better predictions. Or do we do both and make the appropriate comparisons between them.

          If we take a model to or beyond it limits, we are now using in in a situation where it no longer gives valid answers or predictions. This is stupidity. The sensible behaviour is to develop a new model appropriate for the situation at hand.

          I don't use DC models for AC circuits. Nor do I use low frequency models for high frequency circuits. I don't use dam construction models to construct aircraft.

          The models applicable for a situation may use similar mathematical methodologies, but the models are different.

          Let me ask you a question about "truth". Does "eternity" exist? Why does the universe exist? Where does "evil" come from? Does "evil" even exist? What is "evil"?

          These are not questions that science has a hope of answering. These are metaphysical/religious questions.

          The problem that has arisen is the "belief" that science can answer all questions. By the very definition of science, there are questions outside of its domain. Questions it cannot answer because they are not about things that can be tested.

          Keep in mind that famous insult, "he is not even wrong", and recognise that science has its limits.

          Science is fun, it is interesting and can be exciting and insightful into understanding the physical universe about us.

          reply to this | link to this | view in chronology ]

          • identicon
            Lawrence D’Oliveiro, 24 Mar 2016 @ 8:43pm

            Re: A model is not proven "true", at most, it can be proven "false".

            So that is your model of science? Can you prove it is “true”?

            reply to this | link to this | view in chronology ]

            • identicon
              Anonymous Coward, 25 Mar 2016 @ 5:46am

              Re: Re: A model is not proven "true", at most, it can be proven "false".

              I don't have to prove it "true". This is the very essence of science, models that produce predictions or outcomes for which experiments can be developed in which we can test the model to determine if the model is false. If the model is false, then so be it. I can change my model. Even if the model is false in specific circumstances, that model can still be useful in other circumstances.

              You, on the gripping hand, believe that your models are "true", it behooves you to therefore demonstrate that "truth", if you think you arguments are of any merit. The ball is actually in your court. Nothing you have said has demonstrated any hint of being worthwhile considering.

              You are one of those who want others to prove their views true so that you don't have to prove your views true. Instead of actually demonstrating that their views are false, you take the feeble-minded way of politicians. By this, you think you have one-upmanship. All it demonstrates is your lack of coherent, logical cogitation.

              You regularly demonstrate a lack of awareness of the difference between metaphysics and science. You also regularly demonstrate a lack of understanding of what science is.

              Do you understand the concept of piecewise linearisation? What is the function of this process? Under what circumstances can it be used? Under what circumstances can it not be used? Why have I asked these questions? Well, you may ask. I'll let you try and think your way past that. If you can actually work out a reasonable reason why, you might well be on your way to understanding what science is.

              One last note: no matter how much evidence you have for a particular model in science, there are no guarantees that the specific model is "true". All you can say is that we have no negative evidence as yet. If you want "truth", go study religion and metaphysics.

              reply to this | link to this | view in chronology ]

              • identicon
                Lawrence D’Oliveiro, 25 Mar 2016 @ 1:44pm

                Re: I don't have to prove it "true".

                Then how do I know what you are saying is “true”? What gives you the special right to spout claims without having to back them up?

                reply to this | link to this | view in chronology ]

                • identicon
                  Anonymous Coward, 25 Mar 2016 @ 6:37pm

                  Re: Re: I don't have to prove it "true".

                  Ummm - nothing is "true".

                  And until you understand this, you will be tormented to your wits end.

                  reply to this | link to this | view in chronology ]

                  • icon
                    JoeCool (profile), 25 Mar 2016 @ 10:50pm

                    Re: Re: Re: I don't have to prove it "true".

                    It's clear Lawrence (let's call him Larry) isn't an scientist or engineer. Science is about determining if a model of a process is consistent over a range of values. So as you say, nothing is "true", it's consistent with experimental data over a range. "Truth" is left to philosophers and poets. It has no place in science and engineering.

                    reply to this | link to this | view in chronology ]

                  • identicon
                    Lawrence D’Oliveiro, 27 Mar 2016 @ 1:09am

                    Re: Ummm - nothing is "true".

                    Is that “true”?

                    reply to this | link to this | view in chronology ]

      • identicon
        mpc755, 24 Mar 2016 @ 8:49pm

        Re: Re: Dark matter is displaced by matter

        'Empty' space has mass which is displaced by matter. I am going to use the term dark matter to describe this mass.

        Dark matter is displaced by matter.

        Dark matter displaced by matter pushing back and exerting pressure toward matter is gravity.

        reply to this | link to this | view in chronology ]


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