The HOTW-paper explicitly discusses that FDM does fit "core aspects" of dwarf galaxies (search the article for this keyword). That's the point.(adsbygoogle = window.adsbygoogle || []).push({});

The trouble with MOND is that while it is an equation that gives an excellent fit for a class of phenomena in a small range, it is completely inconsistent if promoted to a fundamental law of nature. As such it breaks relativity, conservation laws (besides giving ridiculous predictions outside that small range, as highlighted in Dodelson's "The real problem with MOND" ). If faced with this problem, people usually point out that MOND may be embedded into Bekenstein's tensor-vector-scalar gravity theory. But as the name suggests, "tensor-vector-scalar gravity" is standard gravity with... extra fields added, which must be argued to be otherwise unobserved. So it's just another kind of "dark stuff" theory, after all.

A good historical analogue of the MOND formula is the Rydberg formula. At the time when it was proposed, it was the best formula in fitting certain atomic spectra while existing physical theory could not explain any of this. Still, the Rydberg formula is not a fundamental law of nature, instead it is an effect of a more fundamental theory, even if that fundamental theory was discovered only much later.

While it may be fun to speculate that for the MOND formula that more fundamental theory is a de Sitter version of AdS/CFT, this argument is almost as hand-wavy as the argument for LQC from LQG. As long as there is no argument with a minimum of mathematical decency, something living up to the standards of 20th century theoretical physics, we can have endless speculation, but no conclusion.

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# I Implications of validating loop quantum cosmology

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