Report on One common gravitational scaling relation for LT/ET galaxies and galaxy clustersby Frank PohlmannIn the quoted paper, the author, starting from the claim that in the low-field-strength limit thegravitational scaling relation is common to LT/ET galaxies and clusters, builds up a theoreticalframework (based on 5 postulates) which leads to a functional form for the acceleration-fieldstrength relation (reported in Eq. 4, 5). Moreover, a value for the critical field strength g 0 , inagreement with that of MOND, is re-obtained.To me, the paper contains a series of issues.In the paper, the author claims “we are not aiming to provide a modified,,,,,gravity theory”.However, from the treatment used, gravity (even in the weak field) seems to be an emergentphenomenon, similar to “entropic gravity” or “Verlinde’s proposal”. As is known, there is noconsensus on this way of thinking of gravity. In the submitted paper, gravity is described as a PPPprocess, acceleration comes from shot noise, and a microscopic mass scale arise in gravitation.Protons, electrons, and neutrons are the microscopic gravitational charges.As the author writes “we will sketch a derivation of eq. 4 and 5, ….on physical insight, rather thandetailed calculations”. Physical insight is very important in physics, but if one can add a complete,mathematical description of the claims it is certainly better.Moreover, apart from the non-standard way of describing gravity, which nobody can assure iscorrect, the results are based on 4 (+1) postulates Gravitational field is in a coherent state Gravity is strictly attractive at all scales in the weak field limit the acceleration of test objects equals the root of the field fluctuation relation (7) for the interaction cross sectionAs an example, concerning the second assumption, it is known, that on cosmological scales gravityis repulsive. A fifth postulate is added, the CSP.In summary, the results obtained are based on too many assumptions whose validity is based onlyon the ability to re-obtain a formula resembling MOND’s. I am not so sure this is enough to provethat the author’s idea is correct.The author, in the introduction, implicitly reaches the conclusion that if RAR is valid for spiralgalaxies, and ET, then it should be a genuine physical law (“If the RAR….”). Finally, he claims thatthere is a common scaling law (a dyn ) in the weak-field limit, to galaxies and clusters.Several papers have been written on the RAR not being a physical (some cited by the author).Grudic et al (2020) (MNRAS Volume 496, Issue 1, Pages L127–L132,) concludes that the acceleration scalein MOND, present in RAR, is an emergent phenomenon. Similar conclusions are reached byRodrigues et al. (2018, Nature Astronomy, 2, 668), together with a paper the author is citing (Chan& Del Popolo 2020). In this last paper, it is shown that the RAR is not universal and scaleindependent.It is not valid for clusters.The only point in favour of the submitted paper is that despite the many assumptions (postulates) itreproduces somehow a RAR-like expression. Unfortunately, the author claims that the quotedrelation is valid for galaxies and clusters, against several previous studies (I did not cite all papers
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