Does the external field effect prove MOND over dark matter?

In summary, MOND, or Modified Newtonian Dynamics, is a theory proposed as an alternative to the existence of dark matter. It suggests that the observed discrepancies in galactic rotation curves can be explained by modifying the laws of gravity, rather than the presence of unseen matter. The external field effect, which refers to the observed change in the rotation curves of galaxies when influenced by a nearby massive object, is seen as evidence for MOND over dark matter. Other observations such as the radial acceleration relation, the Tully-Fisher relation, and the distribution of matter in galaxy clusters also support MOND over dark matter. However, the external field effect has been criticized for being unreliable and there is currently no consensus among scientists on whether MOND or dark
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paper on external field effec
this paper,

Testing the Strong Equivalence Principle: Detection of the External Field Effect in Rotationally Supported Galaxies

Kyu-Hyun Chae1

, Federico Lelli2, Harry Desmond3, Stacy S. McGaugh4, Pengfei Li4, and James M. Schombert5 Published 2020 November 20 claims a 4 sigma detection, and that dark matter cannot reproduce this.

i understand this is only 153 galaxies and not 153 million galaxies, but if the results hold up, does this mean MOND?
 
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1. What is MOND and how does it differ from dark matter?

MOND, or Modified Newtonian Dynamics, is a theory that proposes a modification to Newton's laws of gravity to explain the observed rotation curves of galaxies without the need for dark matter. It suggests that instead of a constant acceleration, the force of gravity decreases at large distances. This is in contrast to the theory of dark matter, which proposes the existence of invisible matter that provides the extra gravitational pull needed to explain the rotation curves.

2. How does the external field effect support MOND over dark matter?

The external field effect refers to the observation that the dynamics of a system can be affected by an external gravitational field. In MOND, this effect is explained by the modification of Newton's laws, while in dark matter, it is explained by the gravitational pull of unseen matter. The external field effect has been observed in several systems, such as galaxy clusters, and is consistent with the predictions of MOND, providing evidence for this theory over dark matter.

3. What evidence exists for the existence of dark matter?

There is strong evidence for the existence of dark matter from a variety of sources, including the rotation curves of galaxies, the gravitational lensing of light, and the cosmic microwave background radiation. These observations cannot be explained by MOND alone and require the presence of additional matter that does not interact with light, hence the term "dark" matter.

4. How does the external field effect impact our understanding of gravity?

The external field effect challenges our current understanding of gravity, as it suggests that the laws of gravity may need to be modified at large distances. This could have significant implications for our understanding of the universe and its evolution. However, further research and observations are needed to fully understand the implications of this effect on our understanding of gravity.

5. What are the potential implications of MOND being proven over dark matter?

If MOND is proven to be the correct theory to explain the observed phenomena, it would have significant implications for our understanding of the universe. It would require a re-evaluation of our current theories and models, and could potentially lead to new discoveries and insights into the nature of gravity and the universe as a whole.

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