Dark Matter
A hypothetical form of matter that is thought to account for approximately 27% of the mass-energy content of the universe and does not emit or reflect any electromagnetic radiation, making it undetectable by conventional means.
Dark matter's existence is inferred from its gravitational effects on visible matter, radiation, and the large-scale structure of the universe. It is not 'dark' in the sense of being black, but rather 'dark' because it doesn't interact with light.
Word relationships
- Visible matter: Matter that interacts with light and can be directly observed.
Commonly confused with
- Dark Energy: Dark Matter is a form of matter that exerts gravitational pull, while Dark Energy is a hypothetical form of energy that exerts a repulsive force, causing the universe's accelerated expansion.
Collocations
- cold dark matter
- warm dark matter
- dark matter halo
- dark matter particles
Example sentences
- "The rotation curves of galaxies suggest the presence of a significant amount of invisible Dark Matter." Discussing cosmic composition.
- "Understanding the nature of Dark Matter is one of the biggest unsolved mysteries in modern physics and cosmology." Referring to a scientific mystery.
Memory hook
It's 'DARK' because we can't see it, but it's 'MATTER' because it has gravity. Invisible Gravity
When not to use
Do not use 'dark matter' to refer to ordinary invisible matter (like dust clouds) or simply 'missing' matter. It's a specific scientific concept for a new type of matter.
Fun facts
- Despite its name, dark matter is not made of black holes, dead stars, or gas clouds; it's thought to be composed of exotic, as-yet-undiscovered particles.
- Scientists are conducting experiments deep underground to try and directly detect dark matter particles colliding with ordinary matter.
Related words
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