A severe challenge to the modified Newtonian dynamics phenomenology in our galaxy

Man Ho CHAN, Ka Chung LAW

Research output: Contribution to journalArticlespeer-review

Abstract

Modified Newtonian dynamics (MOND) is one of the most popular alternative theories of dark matter to explain the missing mass problem in galaxies. Although it remains controversial regarding MOND as a fundamental theory, MOND phenomenology has been shown to widely apply in different galaxies, which poses challenges to the standard Lambda cold dark matter model. In this article, we derive analytically the galactic rotation curve gradient in the MOND framework and present a rigorous analysis to examine the MOND phenomenology in our Galaxy. By assuming a benchmark baryonic disk density profile and two popular families of MOND interpolating functions, we show for the first time that the recent discovery of the declining Galactic rotation curve in the outer region (R ≈ 17–23 kpc) can almost rule out the MOND phenomenology at more than 5σ. This strongly supports some of the previous studies claiming that MOND is neither a fundamental theory nor a universal description of galactic properties. Copyright © 2023 The Author(s). Published by the American Astronomical Society.
Original languageEnglish
Article number24
JournalThe Astrophysical Journal
Volume957
Issue number1
Early online dateOct 2023
DOIs
Publication statusPublished - Nov 2023

Citation

Chan, M. H., & Law, K. C. (2023). A severe challenge to the modified Newtonian dynamics phenomenology in our galaxy. The Astrophysical Journal, 957(1), Article 24. https://doi.org/10.3847/1538-4357/acf8c0

Fingerprint

Dive into the research topics of 'A severe challenge to the modified Newtonian dynamics phenomenology in our galaxy'. Together they form a unique fingerprint.