An international team of researchers, including physicists from the University of St Andrews, Scotland, "brought back to life" the previously "debunked" theory of gravity, arguing that the movement of stars inside a dwarf galaxy is slower if such a galaxy is located next to a massive galaxy.
In their study, the team, led by Pavel Kroupa, a professor at the University of Bonn, Germany, and Charles University in Prague, Czech Republic, critically analyzed a study previously published in the journal Nature that claims to have found evidence of the failure of a modified Newtonian dynamics (modified Newtonian dynamics, MOND). According to this early study, the MOND theory may not be true because the motion of stars inside the dwarf galaxy NGC1052-DF2, a small galaxy of roughly 200 million stars, was too slow compared to calculations based on this theory of gravity.
MOND theory is an alternative to Einstein's General Theory of Relativity and allows you to describe the motion and interaction of astronomical objects on a large scale without involving the concept of dark matter and dark energy, "adding" additional gravity in places where gravity is relatively weak. Where gravity is relatively strong, for example in the solar system, the parameters of the equations of the MOND theory are close to those for traditional Newtonian dynamics.
In their new analysis, Kroupa and his team show that the scientific work they criticized did not take into account the gravitational effects of massive objects in the vicinity of the dwarf galaxy under consideration on the movement of stars within it. In other words, if a dwarf galaxy is located close to a massive galaxy - which is exactly the case in this case - then the movement of stars in it will occur more slowly, the researchers show.
In conclusion, Kroupa said: “Theories of MOND have already been predicted 'death' many times, and relevant studies have been published even in highly respected journals. However, so far none of these claims have stood up to well-founded scrutiny.”
The work of Kroupa and his colleagues is also published in the journal Nature.
