- #1
Loren Booda
- 3,125
- 4
Can and do they exist primarily separate from ordinary matter, and how might they be detected (e. g., gravitational lensing, Newtonian mechanics)?
Loren Booda said:Can and do they exist primarily separate from ordinary matter, and how might they be detected (e. g., gravitational lensing, Newtonian mechanics)?
SpaceTiger said:As for planets, they are dark matter, whatever they're composed of, because they don't emit enough light for us to see them beyond the solar system. If there were 10^17 Earth's floating around inside of our galaxy, we wouldn't necessarily know about it. We have good reasons to think, however, that normal planets can't be the dominant form of dark matter.
ohwilleke said:The term "dark matter" is usually used as a term of art to mean non-bayronic matter that is not visible which accounts for phenomena not explained by GR and visible matter and "ordinary" matter which is not visible.
SpaceTiger said:I realize that people often speak that way, but it's poor terminology and technically incorrect. If they mean that, they should say WIMPs or non-baryonic dark matter (depending on which they mean).
Because it is non-baryonic!selfAdjoint said:BTW how is "non-baryonic dark matter" better than "dark matter"?
selfAdjoint said:And what if they don't want to specify either one?
BTW how is "non-baryonic dark matter" better than "dark matter"?
Dark matter is a type of matter that does not emit or interact with electromagnetic radiation, making it invisible to telescopes and other instruments used to study the universe. Its existence is inferred from its gravitational effects on visible matter, such as galaxies, stars, and planetoids.
It is estimated that dark matter makes up about 27% of the total mass-energy of the universe. This is significantly more than the amount of visible matter, which makes up only about 5% of the universe.
While dark matter cannot be directly observed, it is believed to make up the majority of the mass in galaxies, including stars and planetoids. However, because it does not interact with light, it is impossible to detect these objects using traditional methods.
Dark matter and regular matter have very different properties. Regular matter, which makes up everything we can see and interact with, is composed of atoms and subatomic particles such as protons, neutrons, and electrons. Dark matter, on the other hand, is thought to be made up of different types of particles that do not interact with light.
Scientists are constantly studying and researching dark matter to better understand its properties and role in the universe. Some current research includes using advanced telescopes and detectors to try to directly detect dark matter particles, studying the effects of dark matter on the formation and evolution of galaxies, and exploring alternative theories to explain the existence of dark matter.