Some repetitive mistakes and misconceptions about DM, MOND, TeVeS, and cosmology

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SUMMARY

The discussion centers on the validity of Modified Newtonian Dynamics (MOND) in predicting cosmic phenomena, particularly the cosmic background radiation. A 2011 Physical Review Letters article highlights MOND's accurate prediction of the first-to-second peak amplitude ratio (A1:2 = 2.4) compared to the falsified LCDM-1999 prediction (A1:2 = 1.8). Despite claims of MOND's irrelevance, it continues to receive attention in top journals and has demonstrated empirical success unmatched by LCDM. The conversation also clarifies that TeVeS is not a generalization of MOND but a specific relativistic attempt, emphasizing that MOND remains a viable model in cosmology.

PREREQUISITES
  • Understanding of Modified Newtonian Dynamics (MOND)
  • Familiarity with cosmic background radiation and its significance
  • Knowledge of the LCDM model and its predictions
  • Basic concepts of relativistic physics and TeVeS theory
NEXT STEPS
  • Research the implications of MOND on cosmic background radiation predictions
  • Study the differences between MOND and LCDM models in cosmology
  • Examine the role of TeVeS in the context of MOND and its limitations
  • Investigate recent empirical tests of MOND against dark matter theories
USEFUL FOR

Astronomers, cosmologists, and physics students interested in alternative theories of gravity and their implications for cosmic phenomena.

juanrga
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First MOND was the first to predict the cosmic background radiation, as repeated in this recent article (2011)

http://prl.aps.org/abstract/PRL/v106/i12/e121303

in its page 121303-3:
A simple model motivated by MOND provided the only successful a priori prediction of the first-to-second peak amplitude ratio of the acoustic peaks of the cosmic background radiation: A1:2 = 2.4 predicted [21] vs 2.34 ± 0.09 measured [22].

Whereas the LCDM-1999 prediction was falsified (A1:2 = 1.8). Only after the WMAP data was known (A1:2 = 2.34 ± 0.09), the LCDM model was amended, to posteriori, to fit the available data.

Second, contrary to unfounded claims that MOND is dead, Physical Review Letters considers MOND serious enough to publish this very recent paper

http://prl.aps.org/abstract/PRL/v106/i12/e121303

and to Select it for a Viewpoint in Physics. And Science and Nature news consider this paper serious enough to launch news

http://news.sciencemag.org/sciencenow/2011/02/more-evidence-against-dark-matte.html?ref=ra

http://blogs.nature.com/news/2011/02/post_73.html

Maybe it is all because MOND has done another prediction, which has been brilliantly confirmed once again, whereas the LCDM model fails once again. See figure 2 in the PRL article and also the caption of the figure:
PRL-article said:
The data are well removed from the expectation of the standard cosmology (upper line), but follow the prediction of MOND (lower line) with no fitting whatsoever.
As reported in Science news (link above)
Jerry Sellwood said:
The real strength of Stacy's paper is that it points to something that can't be explained in cold dark matter, irrespective of whether MOND is right.

Third, TeVeS is not the relativistic generalisation of MOND but only a particular attempt to obtain a relativistic MOND. A violation of TeVeS does not imply a violation of MOND as some pretend...

In despite of repetitive misconceptions and mistakes MOND continues to work as well as it has been doinf in hundred of tests during decades. And in despite of so many premature claims that it «was abandoned» or «is dead». MOND continues to be highlighted in top-journals and in science news thanks to its empirical success, never rivaled by LCDM.
 
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juanrga said:
Whereas the LCDM-1999 prediction was falsified (A1:2 = 1.8). Only after the WMAP data was known (A1:2 = 2.34 ± 0.09), the LCDM model was amended, to posteriori, to fit the available data.

Presumably, where he says the 'LCDM model was amended' he means that the best fit parameter estimates were amended. This isn't changing a model...

But, we have more data now than 12 years ago. Can MOND model the CMB power spectrum, with its value of a_0 fitted to the galaxy rotation curves, without including dark matter?

Second, contrary to unfounded claims that MOND is dead, Physical Review Letters considers MOND serious enough to publish this very recent paper

http://prl.aps.org/abstract/PRL/v106/i12/e121303

Presumably your post is aimed at me. I don't think I said that MOND was dead, just that I didn't know many people who still take it seriously.

Maybe it is all because MOND has done another prediction, which has been brilliantly confirmed once again, whereas the LCDM model fails once again.

Are you taking commission for these comments? Show me how MOND fits the full WMAP CMB spectrum, and how it models, e.g., the Bullet cluster without CDM, and then we can talk about MOND confirming predictions where LCDM fails.
Given that you have attempted to reopen a locked thread, with essentially no new content (i.e. you never attempted to answer Chalnoth in the original thread), this is done.
 
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