More MOND

It appears to be a MOND autumn in the science glossies, as Science publishes a review on our favourite alternative physics theory and the status of MOND like extensions to general relativity

Earlier we we had a nice little discussion about a paper bu Gentile et al in Nature on galaxy surface densities, with but an oblique hint at MOdified Newtonian Dynamics.

Now Ferreira and Starkman have a Review in Science (326 p812 [sub]), also as "Einstein's Theory of Gravity and the Problem of Missing Mass" Ferreira and Starkman, arXiv.0911.1212.

It is a nice sensible review, discussing both why MOND is considered, and its flaws; including the apparent need for dark matter as well as MOND to account for the dynamics of clusters of galaxies - although low mass neutrinos may suffice for clusters.

A more interesting aspect of the paper is a qualitative discussion of the Tensor-Vector-Scalar (TeVeS) and Generalized Einstein-Aether (GEA) theories.
In particular, even with the additional free parameters, such theories to make falsifiable predictions distinct from ΛCDM dark matter cosmological models.
There is also a brief allusion to the beyond Einstein f(R) theories invoked primarily to explain dark energy.

The original simple MOND is not viable as a general theory of gravity, but MOND like extension of general relativity are potentially interesting, falsifiable alternatives, and future surveys will provide data that will incidentally test these non-standard theories.
Most, or all, will likely prove false.
That is how it is supposed to work.

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