English
Related papers

Related papers: Newtonian Fractional-Dimension Gravity and Galaxie…

200 papers

We resume our analysis of Newtonian Fractional-Dimension Gravity (NFDG), an alternative gravitational model that does not require the dark matter (DM) paradigm. We add three more galaxies (NGC 6946, NGC 3198, NGC 2841) to the catalog of…

General Relativity and Quantum Cosmology · Physics 2025-11-27 Gabriele U. Varieschi

We expand our analysis of Newtonian Fractional-Dimension Gravity (NFDG), an extension of the classical laws of Newtonian gravity to lower dimensional spaces, including those with fractional (i.e., non-integer) dimension. We apply our model…

General Relativity and Quantum Cosmology · Physics 2022-11-08 Gabriele U. Varieschi

This paper continues previous work on a novel alternative model of gravity, based on the theory of fractional-dimension spaces applied to Newton's law of gravitation. In particular, our Newtonian Fractional-Dimension Gravity is now applied…

General Relativity and Quantum Cosmology · Physics 2021-02-15 Gabriele U. Varieschi

This paper introduces a possible alternative model of gravity based on the theory of fractional-dimension spaces and its applications to Newtonian gravity. In particular, Gauss's law for gravity as well as other fundamental classical laws…

General Relativity and Quantum Cosmology · Physics 2021-02-09 Gabriele U. Varieschi

We continue our analysis of Newtonian Fractional-Dimension Gravity, an extension of the standard laws of Newtonian gravity to lower dimensional spaces including those with fractional (i.e., non-integer) dimension. We apply our model to…

General Relativity and Quantum Cosmology · Physics 2021-02-24 Gabriele U. Varieschi

This paper presents a relativistic version of Newtonian Fractional-Dimension Gravity (NFDG), an alternative gravitational model recently introduced and based on the theory of fractional-dimension spaces. This extended version - Relativistic…

General Relativity and Quantum Cosmology · Physics 2021-10-26 Gabriele U. Varieschi

Recent observations of ultra-dwarf galaxy NGC1052-DF2 started an interesting discussion between dark matter hypothesis and modified gravity theories. Reported low velocity dispersion (< 10.5 km/s at 90% confidence level) derived from the…

General Relativity and Quantum Cosmology · Physics 2019-12-10 Tousif Islam , Koushik Dutta

The Ultra-Diffuse galaxy NGC1052-DF2 has recently been under intense scrutiny because from its kinematics it has revealed to be "extremely deficient" in dark matter, if not lacking it at all. This claim has raised many questions and…

General Relativity and Quantum Cosmology · Physics 2022-11-09 Enrico Laudato , Vincenzo Salzano

Recent observations of anomalous line-of-sight velocity dispersions of two ultra-diffuse galaxies (UDGs) provide a stringent test for modified gravity theories. While NGC 1052-DF2 exhibits an extremely low dispersion value ($\sigma \sim…

General Relativity and Quantum Cosmology · Physics 2020-08-04 Tousif Islam

We model the velocity dispersion of the ultra-diffuse galaxy NGC 1052-DF2 using Newtonian gravity and modified gravity (MOG). The velocity dispersion predicted by MOG is higher than the Newtonian gravity prediction, but it is fully…

General Relativity and Quantum Cosmology · Physics 2018-11-08 J. W. Moffat , V. T. Toth

The kinematics of the ultra-diffuse galaxy (UDG) 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…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-06 Esha Bhatia , Sayan Chakrabarti , Sovan Chakraborty

[abridged] We explore the possibility that the dark matter (DM) component in galaxies may originate fractional gravity. In such a framework, the standard law of inertia continues to hold, but the gravitational potential associated to a…

Astrophysics of Galaxies · Physics 2023-06-07 Francesco Benetti , Andrea Lapi , Giovanni Gandolfi , Paolo Salucci , Luigi Danese

Recently we put forward a framework where the dark matter (DM) component within virialized halos is subject to a non-local interaction originated by fractional gravity (FG) effects. In previous works we demonstrated that such a framework…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-08 F. Benetti , A. Lapi , G. Gandolfi , M. Adil Butt , Y. Boumechta , B. S. Haridasu , C. Baccigalupi

The line of sight velocity dispersion of the ultra-diffuse galaxies (UDGs) NGC1052-DF2 and NGC1052-DF4 have been reasonably explained only with the baryonic matter, without requiring any dark matter contribution. The comparable ratio…

General Relativity and Quantum Cosmology · Physics 2023-09-19 Esha Bhatia , Sayan Chakrabarti , Sovan Chakraborty

The emergence of the Ultra-Diffuse Galaxies in recent years has posed a severe challenge to the galaxy formation models as well as the Extended Theories of Gravity. The existence of both dark matter lacking and dark matter dominated systems…

General Relativity and Quantum Cosmology · Physics 2024-07-26 Filippo Bouchè , Salvatore Capozziello , Ciro De Simone , Vincenzo Salzano

Recently van Dokkum et al. (2018b) reported that the galaxy NGC 1052-DF2 (DF2) lacks dark matter if located at $20$ Mpc from Earth. In contrast, DF2 is a dark-matter-dominated dwarf galaxy with a normal globular cluster population if it has…

Astrophysics of Galaxies · Physics 2022-03-09 Moritz Haslbauer , Indranil Banik , Pavel Kroupa , Konstantin Grishunin

AGC 114905 is a dwarf gas-rich ultra-diffuse galaxy seemingly in tension with the cold dark matter (CDM) model. Specifically, the galaxy appears to have an extremely low-density halo and a high baryon fraction, while CDM predicts dwarfs to…

Astrophysics of Galaxies · Physics 2024-09-25 Pavel E. Mancera Piña , Giulia Golini , Ignacio Trujillo , Mireia Montes

In a series of recent papers we put forward a ``fractional gravity'' framework striking an intermediate course between a modified gravity theory and an exotic dark matter (DM) scenario, which envisages the DM component in virialized halos…

General Relativity and Quantum Cosmology · Physics 2024-07-25 Francesco Benetti , Andrea Lapi , Giovanni Gandolfi , Stefano Liberati

Ultra-Diffuse galaxies are gravitational systems with quite varied properties. On one hand we have cases like DF2 and DF4, both observed by the Dragonfly Array Telescope, claimed to be highly-deficient in dark matter. On the other hand, we…

General Relativity and Quantum Cosmology · Physics 2023-05-31 Enrico Laudato , Vincenzo Salzano

The recent observation of the ultra-diffuse galaxy NGC 1052-DF2 shows a galaxy may lack dark matter. Usually dark matter is much more abundant than stellar in galaxy environment. This dark matter to baryon mass ratio is generally larger…

Astrophysics of Galaxies · Physics 2020-05-06 Ran Huo
‹ Prev 1 2 3 10 Next ›