Year milestone 1962
Dark energy is the far more dominant force of the two, accounting for roughly 68 percent of the universe’s total mass and energy
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| Dark energy is the far more dominant force of the two, accounting for roughly 68 percent of the universe’s total mass and energy.
Dark matter makes up 27 percent. And the rest – a measly 5 percent is all the regular matter we see and interact with every day. The velocity of rotation for spiral galaxies depends on the amount of mass contained in them, But the outer arms of the Milky Way are rotating much too fast to be consistent with the amount of matter that we know exists in them. Such fast rotation is possible only when there is more mass, and that extra mass is believed to come from dark matter. Dark matter is a hypothetical form of matter. The majority of dark matter is thought to be composed of some as-yet-undiscovered subatomic particles. The name dark matter refers to the fact that it does not appear to interact with observable electromagnetic radiation, such as light. It is thus invisible (or ‘dark’) to the entire electromagnetic spectrum, making it extremely difficult to detect. Dark matter interacts with the rest of the universe only through its gravity (that’s how we know it exists). The material is considered to be a ‘matter’ since it has gravitational attraction and it is ‘dark’ because it does not seem to interact with light (or any part of the electromagnetic spectrum). Are Black Holes Dark Matter?Black holes could be considered as a dark matter for the reasons mentioned below: Almost collision-less. They are stable (if sufficiently massive) They have non-relativistic velocities. They formed very early in the history of the universe. In March 2016, 3 groups of researchers proposed that Black Holes had a primordial origin. Results from 2 groups are consistent with the scenario that almost all dark matter is made of primordial black holes. 3rd group concluded that black holes contributed to only less than 1% of total dark matter. Download 2.63 Mb. Share with your friends:
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