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CMBR - a possible alternative explanation?

  1. Mar 28, 2007 #1
    How can we be sure that the Cosmic Microwave Backgound Radiation is a relic of the big bang and not a reflected echo of the sun's solar wind after it's interaction with the heliopause?

    I ask this because I read an article some years ago which indicated that one of the voyagers had detected a radio signal which had a 'signature' identical to a solar event which passed it sometime earlier. THis 'echo' was then positively identified as an echo of that earlier solar activity.

    How can it be proven that that CMBR is extrasolar apart from taking measurements outside the solar system ?.
     
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  3. Mar 28, 2007 #2

    Wallace

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    How would this explanation lead to an isotropic signature to within 10^-5 ? How would it explain the observed power spectrum of the anisotropies that are seen? The cosmic origin explains these, so this idea would need to do better at both these points to be a reasonable explanation.
     
  4. Mar 28, 2007 #3

    marcus

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    I agree with Wallace and also point to the temperature of the CMBR.

    the wavelength mix is an almost perfect fit to a blackbody curve---in other words it is identical to the radiation from a very cold body at temp of about 2.75 kelvin.

    1. I can't think of any way the solar wind, which is pretty hot, could produce blackbody radiation of temperature 2.75 kelvin---and nothing else---and have it be essentially the same from all directions.

    wind=hot, Cmb=very very cold, liquid helium temperature

    But I could be missing something! If there is a sound physical mechanism, I'd love to see it explained.
    ==================

    2. the CMB was not a complete surprise. In the Forties some guys predicted radiation of about that temperature----I think they said 5 kelvin, as a rough guess. because hydrogen plasma would have combined to neutral hydrogen and gone transparent---they had it figured out---and the universe would then have expanded enough to bring the temperature of the plasma radiation down to a few kelvin.
    They had it figured out in the Forties already, or 1950 maybe. I think George Gamow was involved in that.

    Later other people predicted (on the same cosmological grounds) that we'd see blackbody radiation with that temperature----a few kelvin.

    and then it was seen.

    there was no other prediction on the books that we'd see around 3 kelvin blackbody from some other (non-cosmological) source like some solarwind mechanism.

    3. the mechanism is extremely simple and straightforward---the plasma cools, becomes transparent---so the radiation (at about 3000 kelvin) is released---and the subsequent expansion is just enough to bring it down to 2.75 kelvin.

    all the numbers click into place.

    I'd sayalternative explanations, if they exist at all, are likely either to not be serious science or to be Rube Goldberg
    ==============

    for that reason I, for one, would be delighted and fascinated if you could find a URL link to a peer-reviewed professional article proposing an alternative mechanism for how radiation just like observed could arise!

    bring in a link if you can. Love to see established ideas challenged by competent people:smile:
     
    Last edited: Mar 28, 2007
  5. Mar 28, 2007 #4

    Chronos

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    The perfect black body spectrum of the CMBR rules out stars as the source of CMB photons. No amount of scattering or diffusion can alter that conclusion by science as we know it.
     
  6. Mar 29, 2007 #5
    Whoaa there chaps, I asked a simple question, What I got seems to be a suggestion that either I do not believe in the big bang or that I feel CMBR IS caused by something else, neither is true. As sure as radiation hits a body and can be reflected at a lower energy - there are plenty of examples of this - UV light in a disco can reflect off certain materials and produce visible light. The effects and process's that occur [or may occur] at the heliopause are to la large extent unknown, however the CMBR appears I simply feel it would be wise to rule out any other possibility - as to it's temperature and distribution, coincidences DO happen. Good science is not only about linking phenomina but also discounting other causes. Anyway thanks for your help it gives me a place to start - I'm new to cosmology but not new to science. Incidentally I have not seen this written elsewhere, it's my question, the big bang is a hell of a thing to grasp, I'd just like to have some confidence in it. I like to question and probe what I'm told, whrn I was at school there was no plate techtonics, there was life [and canal]on Mars, and the universe was steady state.
     
    Last edited: Mar 29, 2007
  7. Mar 29, 2007 #6

    Garth

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    Well Welcome to these Forums BrainDwarf!

    Keep asking questions in order to understand.

    An open mind and and readiness to intelligently question the accepted norm is always healthy in science, but you have a mountain to climb if you want to provide an alternative explanation to the standard one for the CMB

    Garth
     
    Last edited: Mar 29, 2007
  8. Mar 29, 2007 #7
    But the big bang theory can't survive without these fudge factors.

    www.cosmologystatement.org:
    The big bang today relies on a growing number of hypothetical entities, things that we have never observed-- inflation, dark matter and dark energy are the most prominent examples. Without them, there would be a fatal contradiction between the observations made by astronomers and the predictions of the big bang theory. In no other field of physics would this continual recourse to new hypothetical objects be accepted as a way of bridging the gap between theory and observation. It would, at the least, raise serious questions about the validity of the underlying theory.

    But the big bang theory can't survive without these fudge factors. Without the hypothetical inflation field, the big bang does not predict the smooth, isotropic cosmic background radiation that is observed, because there would be no way for parts of the universe that are now more than a few degrees away in the sky to come to the same temperature and thus emit the same amount of microwave radiation.
     
  9. Mar 29, 2007 #8

    marcus

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    Cosmopot the second paragraph is flat-out false.

    what you have is an open letter to the New Scientist where the name at the top of the list of original signers is HALTON ARP.

    And the key paragraph, paragraph two, is simply wrong.

    I agree we should support research into promising alternatives and we DO. A paper just came out yesterday with a very interesting alternative. It was by people receiving support in the usual ways. J. Magueijo and P. Singh.

    Personally I think that more alternative approaches to certain theoretical problems should be supported---particularly alternatives to string theory which is something of a fad or craze at least in the US. Overemphasis on one approach can stifle creative people.

    But there is quite a bit of support nevertheless. I think Halton Arp, for some reason, thinks that he deserves more than he gets and has somehow gotten himself excluded from the mainstream so that he is beyond the pale. But that really is a separate issue.
     
  10. Mar 29, 2007 #9

    marcus

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    Here is the 2004 open letter in full, which Cosmopot quoted the first couple of paragraphs

    ===quote from Arp and friends "open letter" in New Scientist===
    New Scientist, May 22, 2004)

    The big bang today relies on a growing number of hypothetical entities, things that we have never observed-- inflation, dark matter and dark energy are the most prominent examples. Without them, there would be a fatal contradiction between the observations made by astronomers and the predictions of the big bang theory. In no other field of physics would this continual recourse to new hypothetical objects be accepted as a way of bridging the gap between theory and observation. It would, at the least, raise serious questions about the validity of the underlying theory.

    But the big bang theory can't survive without these fudge factors. Without the hypothetical inflation field, the big bang does not predict the smooth, isotropic cosmic background radiation that is observed, because there would be no way for parts of the universe that are now more than a few degrees away in the sky to come to the same temperature and thus emit the same amount of microwave radiation.

    Without some kind of dark matter, unlike any that we have observed on Earth despite 20 years of experiments, big-bang theory makes contradictory predictions for the density of matter in the universe. Inflation requires a density 20 times larger than that implied by big bang nucleosynthesis, the theory's explanation of the origin of the light elements. And without dark energy, the theory predicts that the universe is only about 8 billion years old, which is billions of years younger than the age of many stars in our galaxy.

    What is more, the big bang theory can boast of no quantitative predictions that have subsequently been validated by observation. The successes claimed by the theory's supporters consist of its ability to retrospectively fit observations with a steadily increasing array of adjustable parameters, just as the old Earth-centered cosmology of Ptolemy needed layer upon layer of epicycles.

    Yet the big bang is not the only framework available for understanding the history of the universe. Plasma cosmology and the steady-state model both hypothesize an evolving universe without beginning or end. These and other alternative approaches can also explain the basic phenomena of the cosmos, including the abundances of light elements, the generation of large-scale structure, the cosmic background radiation, and how the redshift of far-away galaxies increases with distance. They have even predicted new phenomena that were subsequently observed, something the big bang has failed to do.

    Supporters of the big bang theory may retort that these theories do not explain every cosmological observation. But that is scarcely surprising, as their development has been severely hampered by a complete lack of funding. Indeed, such questions and alternatives cannot even now be freely discussed and examined. An open exchange of ideas is lacking in most mainstream conferences. Whereas Richard Feynman could say that "science is the culture of doubt", in cosmology today doubt and dissent are not tolerated, and young scientists learn to remain silent if they have something negative to say about the standard big bang model. Those who doubt the big bang fear that saying so will cost them their funding.

    Even observations are now interpreted through this biased filter, judged right or wrong depending on whether or not they support the big bang. So discordant data on red shifts, lithium and helium abundances, and galaxy distribution, among other topics, are ignored or ridiculed. This reflects a growing dogmatic mindset that is alien to the spirit of free scientific inquiry.

    Today, virtually all financial and experimental resources in cosmology are devoted to big bang studies. Funding comes from only a few sources, and all the peer-review committees that control them are dominated by supporters of the big bang. As a result, the dominance of the big bang within the field has become self-sustaining, irrespective of the scientific validity of the theory.

    Giving support only to projects within the big bang framework undermines a fundamental element of the scientific method -- the constant testing of theory against observation. Such a restriction makes unbiased discussion and research impossible. To redress this, we urge those agencies that fund work in cosmology to set aside a significant fraction of their funding for investigations into alternative theories and observational contradictions of the big bang. To avoid bias, the peer review committee that allocates such funds could be composed of astronomers and physicists from outside the field of cosmology.

    Allocating funding to investigations into the big bang's validity, and its alternatives, would allow the scientific process to determine our most accurate model of the history of the universe.
    ==endquote==

    The red paragraph is false.
    It is false because inflation is not the only way to arrive at thermal equilibrium---same temp in different parts of sky.

    One way to see this is simply to read Magueijo and Singh paper

    (but this has been clear at least since Bojowald's work of 2001).

    Here is M&S paper
    (I will go get a link to it so you can read if you want)
     
  11. Mar 29, 2007 #10

    marcus

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    Hi, I'm back, here is the Magueijo Singh paper
    http://arxiv.org/abs/astro-ph/0703566
    Thermal fluctuations in loop cosmology
    Joao Magueijo, Parampreet Singh
    10 pages


    "Quantum gravitational effects in loop quantum cosmology lead to a resolution of the initial singularity and have the potential to solve the horizon problem and generate a quasi scale-invariant spectrum of density fluctuations. We consider loop modifications to the behavior of the inverse scale factor below a critical scale in closed models and assume a purely thermal origin for the fluctuations. We show that the no-go results for scale invariance in classical thermal models can be evaded even if we just consider modifications to the background (zeroth order) gravitational dynamics. Since a complete and systematic treatment of the perturbed Einstein equations in loop cosmology is still lacking, we simply parameterize their expected modifications. These change quantitatively, but not qualitatively, our conclusions. We thus urge the community to more fully work out this complex aspect of loop cosmology, since the full picture would not only fix the free parameters of the theory, but also provide a model for a non-inflationary, thermal origin for the structures of the Universe."

    If you want the whole 10-page paper all you need to do is go to that page and click on PDF.
     
    Last edited: Mar 29, 2007
  12. Mar 29, 2007 #11
    That appears to be the Emporer's clothes of an explanation. In 50 years of working in classical physics I have never yet seen a phenonemum that could not be explained in simple lay terms. That paper is complete and utter garbage. Compare it for example with papers by Stephen Hawking - all of which are understandable with a good education and sometimes a second read).
     
    Last edited: Mar 29, 2007
  13. Mar 29, 2007 #12

    marcus

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    :biggrin:

    as far as garbage goes, I don't know which Stephen Hawking papers you mean.
    here is a list
    http://arxiv.org/find/grp_physics/1/au:+Hawking/0/1/0/all/0/1

    He hasnt been writing too much for the past 5 years. here are the last three

    1. hep-th/0602091 [abs, ps, pdf, other] :
    Title: Populating the Landscape: A Top Down Approach
    Authors: S.W. Hawking, Thomas Hertog
    Comments: 22 pages, 1 figure
    Journal-ref: Phys.Rev. D73 (2006) 123527

    2. hep-th/0507171 [abs, ps, pdf, other] :
    Title: Information Loss in Black Holes
    Authors: S. W. Hawking
    Journal-ref: Phys.Rev. D72 (2005) 084013

    3. astro-ph/0305562 [abs, pdf] :
    Title: Cosmology from the Top Down
    Authors: Stephen Hawking
    Comments: Talk presented at Davis Inflation Meeting, 2003
    ==================

    My guess is that the Magueijo Singh will have at least as much impact as his "Information Loss in BH" which left a lot of people skeptical.
    But we can't tell the future and that is just my hunch.

    About LAYMAN'S LANGUAGE. how do you know that what Magueijo Singh have to say could NOT be put in terms understandable to an intelligent general reader?
     
  14. Mar 29, 2007 #13

    marcus

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    Magueijo Singh did not INVENT the idea that QG effects can solve the horizon problem (that's the fact of same CMB temp in all directions, inflation invented to solve but turns out not needed).

    This has been know for some time by people doing QG. The cosmological singularity is resolved by being replaced by a bounce and the stuff before bounce had all the time in the world to come to thermal equilibrium!

    This has been implicit in LQC (loop quantum cosmology) work ever since 2001.

    So Magueijo Singh are simply POINTING OUT SOMETHING ALREADY KNOWN in that sentence. They take it a step further in their paper and address the structure problem.

    So it is not important to my point what you call the M-S paper. My point stands regardless of what you think about M-S. I am saying that the second paragraph of Arp's letter is factually wrong.

    He says standard mainstream cosmology COULDNT SURVIVE WITHOUT AN INFLATON. And I am telling you very plainly that it could survive without an inflaton

    Nothing said about mainstream cosmology being right or wrong. you still have to doubt. you still have to test---and test again!

    My point is simply that Arp is not telling the truth in the second paragraph, which I colored red up there.
     
  15. Mar 29, 2007 #14
    I have consistent answer for astrophysics.

    If you agree with the principles:
    a) No solid spacetime. Space and time are given with measurments by physical proccesses (usally waves) which are static with respect to the reference frame;
    b) We accept only real inertial reference frames which generally are limited and are freely-falling frames by the assumption that the local massive mass did not exist;
    c) The reference frame is flat and should be called virtual one because of the above assumption;
    Then I have solved consistently all astronomic problems involving gravity:

    Here are my alternatives: astro-ph/0510535, 0510536, 0512614v3, 0604084, 0605213, 0512614. I am lazy guy and did not find some beautiful ideas from all over the world before I deposited those papers. I had faith to nonlinear dynamics before I came to America. I wanted to identify fractal evidence on galaxy images. L Nottale`s fractal Relativity was my bible. Instead, I got a simple symmetry principle on galaxy patterns and the patterns can be fitted by simple mathematical formulas. Surely, I need to run the program on super-computers to confirm the results. Instead, I submitted my prelimitary result to ApJ, MNRAS. The referees were very positive of my results and asked further physical meaning if possible. Well, I did not know physics politics. Surprisingly I found the physical meaning and naively reported it to the referees that the meaning is against curved spacetime assumption. OK, you must know my following story. The refereees no longer had contacts to me by means of editors. I realized that daring something against the bible, General Relativity, is very dangerous!!

    Human nature is not afread of authority if one feels that truth is by one`s side. I tried to quantize gravity. I am amazed that the quantization is so simple (astro-ph/0604084), while the huge figures like Hawking, Astekar, Lee Smolin, John Baez, etc. are looking for quantum gravity very hard!!! Further, I proposed a model of the universe (astro-ph/0605213). I am amazed that the model can not be simpler yet it can explain most important observations. `Accelerating universe` is very simply explained and the merits of some kind of `big bang` are still there on flat and infinite universe. More importantly, those beautiful theories are combined consistantly as the results of my simple model. Firstly, Joao Magueijo et all`s varying speed of light is my result. Secondly, 90yrs of resisting report of absolute reference frame of the universe is my result. Thirdly, non-universal time and no-time are the relative of my theory. My theory does need improvement but I am confident it stands for truth.
     
  16. Mar 29, 2007 #15

    marcus

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    I admire your courage and your dedication to following your own idea even if you get "burned at the stake" for being a heretic.
    It seems you have developed an idea that involves a preferred reference frame. I do not encourage you, but I respect people willing to go off the beaten track when they actually write technical papers and put them on arxiv and try to get them peer-review published. It shows
    the person's strong independent character.

    So to me it seems significant that you have posted your (possibly crazy) ideas on arxiv.

    and therefore I think we should put the links so people can quickly get these papers if they are curious. OK with you?

    http://arxiv.org/astro-ph/0510535

    http://arxiv.org/astro-ph/0510536

    http://arxiv.org/astro-ph/0512614

    http://arxiv.org/abs/astro-ph/0512614v3

    http://arxiv.org/astro-ph/0604084

    http://arxiv.org/astro-ph/0605213

    http://arxiv.org/astro-ph/0512614
     
    Last edited: Mar 29, 2007
  17. Mar 29, 2007 #16
    It is not crazy at all. The pardigm is felling as you can see:
    http://www.physorg.com/news93793516.html
    Science needs to progress. You can not make your living by resisting against truth and sleeping over your old stuff which needs to be corrected.

    Science needs experiments. We wait for GPB data release and wait for future Planck Mission. Because scientists use tax money they can not cheat common people.
     
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