The kinematics of the ultradiffuse galaxy NGC1052-DF44 is primarily influenced by the presence of dark matter (DM). In this paper, we conduct a contrasting kinematic study of DF44 within the alternative modified gravity framework. In comparison to the Navarro-Frenk-White DM profile, we test three alternative gravity models viz Milgromian dynamics (MOND), characterized by a known acceleration scale, a generic $f(R)$ model, assuming an expansion of the Ricci scalar, and a quantum gravity-inspired renormalization group correction to general relativity (RGGR), which involves the running of the gravitational coupling parameter $G$ with the Universe’s energy scale. For each gravity model, we evaluate the velocity dispersion (VD) of the galaxy beyond the conventional radial isotropic assumption and extend to two anisotropy scenarios, i.e., constant and Osipkov-Merritt. Our results show that all three gravity models can provide consistent fits to the observed VD of DF44; however, only MOND and RGGR remain competitive with the Navarro-Frenk-White profile. Interestingly, the constant anisotropy scenario in all the models is also found to be competitive with the complete isotropic assumption.

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• Alternative gravity theories
• Astrophysical studies of gravity
• Gravitation