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Dec 24, 2017 · The first dark matter problem is that most gravitating matter is dark. Most of the inferred mass that appears to be responsible for the observed gravitational dynamics of large scale structures like galaxies and clusters of galaxies cannot be seen (i.e. is dark). That is, we can't detect it through visible light or any other electromagnetic waves.
May 9, 2018 · That is because dark matter carries five times the mass of ordinary matter and, furthermore, does not directly interact with light. ... would like to understand, at a more fundamental level, what ...
- Lisa Randall
- 2018
Aug 28, 2006 · It is tempting to try to combine the explanations for dark matter and dark energy, but there are great differences between the two. Dark matter pulls and dark energy pushes. That is, dark matter ...
- Matter Or Gravity?
- Comparative Testing
- Young and Old Galaxies
- Dark Matter For The Win?
So far, dark matter has never been observed directly—hence the name. What astronomers observe in the night sky are the consequences of matter that is potentially present: bending of starlight, stars that move faster than expected, and even effects on the motion of entire galaxies. Without a doubt all of these effects are caused by gravity, but the ...
Brouwer and her colleagues selected over 259,000 isolated galaxies, for which they were able to measure the so-called 'Radial Acceleration Relation' (RAR). This RAR compares the amount of gravity expected based on the visible matter in the galaxy, to the amount of gravity that is actually present—in other words: the result shows how much 'extra' gr...
Thus it seems that, at least one dark matter model does appear to work. However, the alternative models of gravity also predict the measured RAR. A standoff, it seems—so how do we find out which model is correct? Margot Brouwer, who led the research team, continues: "Based on our tests, our original conclusion was that the two alternative gravity m...
If it turns out that extra gas cannot explain the difference between the two types of galaxies, then the results of the measurements are easier to understand in terms of dark matter particles than in terms of alternative models of gravity. But even then, the matter is not settled yet. While the measured differences are hard to explain using MOND, E...
- Science X
Jan 28, 2022 · Dark matter is completely invisible. It emits no light or energy and thus cannot be detected by conventional sensors and detectors. The key to its elusive nature must lie in its composition ...
Nov 20, 2020 · The evolution of the universe is a tale of two fluids: dark matter, which doesn't interact with light, and ordinary matter, which does. The big bang left ripples in the dark matter, which under its own gravity began to coalesce into the denser spots. Ordinary matter—then, a hot soup of free-flying protons and electrons—also began to fall ...
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5 days ago · dark matter, a component of the universe whose presence is discerned from its gravitational attraction rather than its luminosity. Dark matter makes up 30.1 percent of the matter -energy composition of the universe; the rest is dark energy (69.4 percent) and “ordinary” visible matter (0.5 percent). Originally known as the “missing mass ...
