Another gravity based explanation of dark matter phenomena taking an approach somewhat similar to that of Deur who is cited at endnote 11. Milgrom (the author of MOND) is cited at endnotes 23, 24, and 25.
We derive the first analytical formula for the density of "Dark Matter" (DM) at all length scales, thus also for the rotation curves of stars in galaxies, for the baryonic Tully-Fisher relation and for planetary systems, from Einstein's equations (EE) and classical approximations, in agreement with observations.
DM is defined in Part I as the energy of the coherent gravitational field of the universe, represented by the additional equivalent ordinary matter (OM), needed at all length scales, to explain classically, with inclusion of the OM, the observed coherent gravitational field.
Our derivation uses both EE and the Newtonian approximation of EE in Part I, to describe semi-classically in Part II the advection of DM, created at the level of the universe, into galaxies and clusters thereof. This advection happens proportional with their own classically generated gravitational field g, due to self-interaction of the gravitational field.
It is based on the universal formula rD=lgg'g' for the density rD of DM advected into medium and lower scale structures of the observable universe, where l is a universal constant fixed by the Tully-Fisher relations. Here g' is the gravitational field of the universe; g' is in main part its own source, as implied in Part I from EE.
We start from a simple electromagnetic analogy that helps to make the paper generally accessible. This paper allows for the first time the exact calculation of DM in galactic halos and at all levels in the universe, based on EE and Newtonian approximations, in agreement with observations.
Peter H. Handel, Klara E. Splett, "Calculation of Dark Matter as a Feature of Space-Time" arXiv:2503.09804 (March 12, 2025) (published in Foundations of Physics (2023) 53:86) https://doi.org/10.1007/s10701-023-00705-x
4 comments:
isn't that Geon which is not stable ?
The lead author has a theory of "quantum 1/f noise" which he has been pushing for 50 years(!), and which they say is somehow at the root of this paper, although they also say their gravitational theory is independent of that origin.
arXiv:2503.11585 [pdf, other] astro-ph.CO gr-qc
Gravitational Redshift from Galaxy Clusters -- a Relativistic Approach
Authors: Enea Di Dio, Sveva Castello, Camille Bonvin
Abstract: The light that we receive from clusters of galaxies is redshifted by the presence of the clusters' gravitational potential. This effect, known as gravitational redshift, is an early prediction of Einstein occurring in any metric theory of gravity. As a direct consequence, the central galaxy, located near the bottom of the gravitational potential, is observed to be more redshifted than the cluster members. In 2011, a first detection of this redshift difference on cluster scales was achieved and compared with theoretical predictions for gravitational redshift in various theories of gravity. However, the interpretation of this result has been challenged by several later studies, which emphasised the possible influence of additional kinematic effects on the observed signal from stacked clusters. In this work, we present the first derivation of all such effects within a relativistic framework, accurate to third order in the weak-field approximation. This framework allows us to correctly capture the hierarchy of terms at the scale of clusters, while accounting for all relativistic effects. We compare our result with previous literature and show that some terms were not properly included, leading to an overestimation of the kinematic contamination. △ Less
arXiv:2503.11174 [pdf, ps, other] gr-qc astro-ph.CO hep-th
Connecting Relativistic MOND Theories with Mimetic Gravity
Authors: Guillem Domènech, Alexander Ganz
Abstract: We find a connection between relativistic Modified Newtonian Dynamics (MOND) theories and (scalar) mimetic gravity. We first demonstrate that any relativistic MOND model featuring a unit-timelike vector field, such as TeVeS or Aether-scalar-tensor theory, can be embedded within a conformal/disformal-invariant framework. Gauge fixing the conformal/disformal symmetry amounts to imposing a constraint on the norm of the vector, the scalar field or the cross contraction. Notably, we find that these constraints can be interchanged as long as the vector and scalar fields remain timelike. This means that relativistic MOND theories may be recasted as a mimetic gravity theory. Lastly, by constructing the fundamental building blocks of a conformal-invariant scalar-vector-tensor theory, we establish a new framework for developing relativistic MOND theories. This perspective offers deeper insight into how non-invertible disformal transformations and conformal/disformal symmetries serve as fundamental principles in constructing viable alternatives to dark matter. △ Less
Submitted 14 March, 2025; originally announced March 2025.
Comments: 17 pages
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