prompter: What is the current understanding of dark matter and dark energy in astrophysics?

assistant: Dark matter and dark energy are currently two of the most mysterious and least understood phenomena in astrophysics. Dark matter is thought to make up about 85% of the total matter in the universe, but it does not interact with light or other forms of electromagnetic radiation, making it invisible to telescopes. Scientists have inferred its presence by observing its gravitational effects on the motions of galaxies and galaxy clusters.

Dark energy, on the other hand, is thought to make up about 70% of the total energy in the universe and is responsible for the accelerating expansion of the universe. Scientists have inferred its presence by observing the large-scale structure of the universe and the cosmic microwave background radiation.

Currently, the leading theoretical explanation for dark matter is that it is composed of weakly interacting massive particles (WIMPs), while the leading explanation for dark energy is that it is a cosmological constant, a term first proposed by Einstein to explain the static nature of the universe.

Despite these explanations, the true nature of dark matter and dark energy remains unknown and is a subject of ongoing research in astrophysics.

prompter: What are some alternative theories to explain dark matter and dark energy?

prompter: What are the ways that scientists are trying to prove or disprove what dark matter and dark energy are?

prompter: Is dark matter dense? Could you explain its density by comparing it to something ordinary that I would be familiar with?

assistant: Dark matter and dark energy are two of the biggest mysteries in astrophysics. Dark matter is believed to make up about 27% of the universe and is invisible, meaning it does not interact with light or other forms of electromagnetic radiation. This makes it difficult to detect directly, but its presence can be inferred from its gravitational effects on visible matter. Dark energy, on the other hand, is thought to make up about 68% of the universe and is responsible for the observed acceleration of the universe's expansion. Despite much study, both dark matter and dark energy remain poorly understood and their exact nature is still unknown.

assistant: Dark matter is the phenomenon that allows the galaxies to spin as fast as they do. Dark energy is the phenomenon that allows the universe to expand. We don't know what either are but we see the effects and were given names.

prompter: I always think that dark matter/energy is just an excuse to make current theories fit with observations, but I know physicians are smarter than that, why is it such a wide spread idea then?

prompter: How can matter be a phenomenon and how can it cause spin?

assistant: Dark matter is referred to a phenomenon because it has not been directly observed. Instead, we have observed what appears to be the gravitational effects of something we cannot perceive using light.

Dark matter does not cause spin. Rather, dark matter is necessary to explain why the stars at the edges of galaxies move as quickly as they do. Because gravity decreases with distance stars further away from the center of a galaxy should be moving more slowly. However the stars at the edges of galaxies move at similar speeds to ones closer to the center. The most likely seeming explanation is that there is additional matter near the edges of the galaxy we are not perceiving.

assistant: Dark mater does not cause things to spin. Scientist observed that stars go faster than they should be. To account for that the scientist came up with dark matter. We can't see it but do to the stars in the galaxies going to fast something is holding them in place. Let me know if I need to explain something else.

prompter: what is the cosmological constant ?