Table of Contents
What does MOND stand for?
Modified Newtonian dynamics
Modified Newtonian dynamics (MOND) is a hypothesis that proposes a modification of Newton’s law of universal gravitation to account for observed properties of galaxies.
Can MOND explain the bullet cluster?
A famous example is the Bullet Cluster, which consists of two such colliding clusters. Observations suggest that dark matter follows the stars in these events, which have a lower total mass than the gas cloud. MOND cannot explain why that is.
When was MOND?
1983
A counter explanation introduced by the Israeli physicist Mordehai Milgrom in 1983, the MOdified Newtonian Dynamics (MOND) theory, says this gravitational pull exists because the rules of gravity are slightly altered.
Does Mond explain gravitational lensing?
Modified Newtonian dynamics (MOND) is an alternative theory of gravity that aims to explain large-scale dynamics without recourse to any form of dark matter. However, the theory is incomplete, lacking a relativistic counterpart, and so makes no definite predictions about gravitational lensing.
Is MOND dead?
MOND is a controversial alternative to general relativity, the prevailing Einstein-inspired understanding of the phenomenon of gravity, that requires dark matter to exist, but this has never been proved. MOND does not require dark matter. The now debunked study claimed MOND was dead.
Are there galaxies with no dark matter?
In 2018, a team led by Yale University astronomer Pieter van Dokkum found that a galaxy called NGC 1052-DF2, some 60 million light-years away from Earth, appears to contain no dark matter.
How many galaxies are there in a bullet cluster?
two
The Bullet Cluster (1E 0657-56) consists of two colliding clusters of galaxies. Strictly speaking, the name Bullet Cluster refers to the smaller subcluster, moving away from the larger one….
| Bullet Cluster | |
|---|---|
| Constellation(s) | Carina |
| Right ascension | 06h 58m 37.9s |
| Declination | −55° 57′ 0″ |
| Number of galaxies | ~40 |
Is Mond relativistic?
Here I briefly review MOND as well as its implementation as a nonrelativistic modified gravity theory, AQUAL. Gravitational lensing and cosmology call for a relativistic gravity theory different from general relativity if dark matter is to be avoided.