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GPB hopefully to end DM nonsense!

  1. Apr 20, 2004 #1
    Hi there dudes.
    Assuming those NASA dudes can find a way to lauch GPB while there's a light breeze in the air... http://einstein.stanford.edu/ .....
    In 16 months time GR could be dead. All the GR trumpeteres around the world who have spent their whole lives whacking anti GR dudes, and believing fanatically in the existance of dark matter (?) and dark energy (????) , will be squashed and the flood gates will be open for the rabid foaming-at-the mouth alternate theory believers to stampede through physics bellowing " WE TOLD YOU SO!!" .
    The grim reality is that it's main use will be another excuse for the string theorists to have there research grants increased. Bah.

    Me, despite what I said to FZ+, I like to believe that GPB WILL get a result which differs from GR prediction. I just can`t condone daft Dark matter , let alone dark energy. The modern concepts of DM/DE, whose current understanding relies heavily on GR, will vanish with GR.

    Dark matter was invented to comprehend galaxy dynamics when observations didn`t corelate with GR. The most central non-corelation is the galactic rotation anomaly. With just obesevational mass, galaxys should not be able to hold themselves together via gravity, the stars they are composed of should just fly out into outer space. Also, galaxy differential spin is very awkward to explain.

    Dark matter was ceratinly the most intuitive response to the incompatable observations. However, time and practice has shown that rigid following of DM leads to bizzare, unbelievable, imcompatible and unobserved physics.

    Young astro physics dudes are warming to MOND, an alternative to GR and dark matter. Skeptics are quick to whack MOND with the argument that it has no theoretic framework. But this is hardly fair. MOND believe is tolerated amongst observational physicists, simply because it gives the best predictions, while DM gives rubbish predictions. Despite this, until very recently, the DM believers have always been the ones who call the shots in astro-physics and have crushed any big movement in the theorectical physics towards explaining MOND. Thus DM theorectical dudes have cut themselves off from the rest of physics, effectively creating and living in their own self-made land of delusion!

    Oh well. Thats why I hope GPB will give anti-GR results, because that will speed up the demise of the dark matter/energy nonsense.

    Based on this hope, I predict that GPB will find that space time warping is higher than expected! Galaxys hold themselves together because the stars in them aren`t traveling through space-time as fast as we thought.
     
    Last edited: Apr 20, 2004
  2. jcsd
  3. Apr 20, 2004 #2
    Dark matter was actually introduced because galaxies rotate differently to what would be suggested by both GR and Newtons law of gravity. A point mass in a galatic potential follows a Keplerian motion so GR is nothing to do with it specifically (although GR does predict it so does just about every other modern theory of gravity).

    The idea DM is not at all absurd. Consider this, we know there is at least x amount of mass in a galaxy because of what light we can see given off by it but we know due to the galaxies rotation that there must be y amount of mass which is greater than x. y-x is the amount of dark matter in the galaxy, this could be something as simple as mass with so little energy that no light is given off, for example we know there are masses of low eneregy hydrogen in galaxies its not too far fetched to believe there will be some that gives off almost no radiation so is unseeable and therefore dark matter.

    Now dark energy is something completely different and is I believe something to do with the cosmological constant. It is a completely different idea to dark matter and really they should have been given different names to differentiate how hugely different as concepts they are (though they're both heavily involved in big bang theory and the fate of the universe and do have opposing effects on the galaxy one is a simple result of our inability to see everything while the other is a result of a scientists possible mistake that we can't really decide on one way or the other).

    Basically the conundrum is that for DM to be nonsense we'd have to see every piece of matter in a particular galaxy which is impractical I'm sure you'll agree. There are other forms of dark matter being considered like Neutrinos which are fully open to your scorn (although they've gone a long way to proving neutrinos exist over the past few years) but there must be some DM out there.
     
  4. Apr 20, 2004 #3

    Nereid

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    Hey meemoe_uk, how about adding your own predictions as to what the results from GPB will be, in the thread that I began for just that purpose?

    To add just one thing to gmorgan's reply: lots of observations attest to the existance of dark matter, not just galaxy rotation curves! For example, weak gravitational lensing in Abell clusters (and others); hydrostatic equilibrium considerations re the IGM (inter-galactic medium), from X-ray observations of rich clusters; application of the virial theorem to motions of galaxies in clusters (and globulars associated with large spirals and ellipticals).
     
  5. Apr 21, 2004 #4
    I can`t easily find that thread, Nereid. The more I look into it, the more I'm convinced that 'space warping' due to moving mass is much higher than GR predicts.

    For those who think I mean all dark matter....
    I mean the modern synthesis of DM,GR and DE.

    There is plenty of dark matter around in the form of cold objects and black holes, and I'm sure there are observations which attest to their existance. But I don`t think DM account for all the strange obsevations; again the best example is galaxy rotation. DM explanation for that is plain daft.
     
  6. Apr 21, 2004 #5

    Nereid

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    Here's that thread.

    Which particular 'strange observations' (other than galaxy rotation)?

    Also, I'm not sure I understand when you say "... 'space warping' due to moving mass is much higher than GR predicts" (apart from what GPB is set out to observe); IIRC, there is at least one set of observations of frame dragging reported, and although the "error bars" are fairly big, the result was entirely consistent with what GR predicts. I'll see if I can find the papers if you're interested.

    There's surely a great deal still to learn about DM, not least its composition! For example, is it axions, SUSY particles of some kind, wimpzillas, ....? Without any significant constraints from observation (other than some cluster density profiles, bulk mass, and implications from CMBR observations), the theoreticians are having a marvellous time! :eek:

    Why do you say that a DM explanation for galaxy rotation curves 'is plain daft'? Personally, I find it interesting that the amount of DM in galaxies is consistently estimated from two independent sets of observations - galaxy rotation curves and weak gravitational lensing (this paper may be more readable).
     
  7. Apr 22, 2004 #6
    Nereid,

    I hear that galaxys are flying around the universe in strange ways. Their kinematics have been very awkward to interpret with DM theorys.

    Space warping - you should check out the GPB website for exactly how and why there is an issue with moving mass. - best click on - ' story of GPB ' under 'news and media'

    Where you say theorectians are having a great time, is where they are living in the world of delusion; conjecturing all sorts of mad matter.

    It's not so much the amount of DM predicted in galaxys by DMtheory, it's the distribution which is too daft to believe. As for two papers which beautifully and 'unexpectedly' converge on the same prediction - Ha! DM dudes have had plenty of time to rig and fine tune their theorys to match subsets of observations. Whatever predictions the papers make, I expect they will fail if they are based around DM.

    nereid, ultimately I won`t be able to answer all your questions because I'm a layman!
    Try this website...
    http://www.astro.umd.edu/~ssm/mond/
    this guys website is better than me in terms of DM whacking.
     
  8. Apr 22, 2004 #7
    Yahoo! GPB was launched april 20th 2004. death to DM!
     
  9. Apr 22, 2004 #8
    If gravitons are in some way compressed as they move through the magnetic field lines of a galaxy this would increase their energy and make gravity stronger over long distances than expected.
     
  10. Apr 23, 2004 #9
    Gravity Probe B
    NASA launched the Gravity Probe B spacecraft to test two as-yet untested predictions of Einstein’s general theory of relativity. It will test for the effect of frame dragging – space dragged around by the Earth’s rotation – and geodetic precession.
    The experiment uses four small, incredibly precise gyroscopes to help detect the small relativistic effects around the Earth. The frame dragging effect will cause a small force to push the gyroscope’s spin axis out of alignment, as it orbits the Earth. And the much larger geodetic effect – warping of space–time – will also affect the gyroscope’s spin, but in a direction that is perpendicular to that of the frame dragging; and so the effects can be measured separately.

    With regard to the ether.
    It seems plausible that large bodies of spinning matter could drag space around. The movement of the ether around a body could stretch the ether – making it wider along the equatorial plane and flatter on the poles. These effects are likely to be extremely small around the Earth but could mimic the dark matter gravitational effect.

    Without looking into the fine detail, I don’t know if results that support GR will affect an ether equivalent. Einstein took nearly a decade to develop GR.
    Would an ether theory take the same time to develop and produce similar or better results? I don’t know.
     
  11. Apr 23, 2004 #10

    russ_watters

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    GR has been studied, developed, refined, supported for the better part of a century. Where have ether theories been all this time?

    It sounds like you are preparing an excuse...
     
  12. Apr 23, 2004 #11

    TeV

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    Russ,everything is ok as long as he pushes his ether theory in TD subforum without abusing SR@GR subforum.There are still some ether theory related posts in the latter and my kind regards to PF admins is to shift them here.

    TeV
     
  13. Apr 23, 2004 #12

    Nereid

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    Did you read Milgrom's article in Scientific American a year or so ago? MOND is certainly a very interesting idea, but as Milgrom himself is clear to point out, it's not an alternative to GR. Oh, and MOND has considerable difficulty with at least one large class of astronomical observations, so why chose MOND and do away with some lines of evidence for DM (but not all)?

    Plenty of work to do to better characterise DM; maybe galaxy collisions, like this one observed by the HST might play a role in that program? Did you know there's a serious proposal to build something called a dark matter telescope?
     
  14. Apr 24, 2004 #13
    No. Didn't Einstein spend the later part of his life trying to develop a unification theory and he never fully dismissed the existence of the ether.
    See this 10 page PDF by Galina Granek:
    http://redshift.vif.com/JournalFiles/V08NO3PDF/V08N3GRF.PDF

    My message is not whether an ether model could match or better GR predictions, but how long would it take to develop a model.

    Time spent on this would not be wasted.
     
    Last edited: Apr 25, 2004
  15. Apr 27, 2004 #14
    I've been reading about GPB and it in itself is amazing. Optical contacting sounds like BS but it's real. An amazing piece of equipment.

    I hope it all works and we get some interesting results.
     
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