system: 
User: Describe the theory of dark matter using zombies.
ChatGPT: The theory of dark matter is a concept in astrophysics and cosmology that proposes the existence of a form of matter that is invisible to us and does not interact with light or any other electromagnetic radiation. This means that it cannot be detected by our telescopes or other instruments that are designed to detect electromagnetic radiation.

One way to think about dark matter is to imagine a group of zombies moving through a city. The zombies are completely invisible to us, and we can't see them with our eyes or any other instruments. However, we can still infer their existence based on the way they affect their surroundings. For example, we might notice that the zombies are causing buildings to shake or objects to move in strange ways, even though we can't see them directly.

In the same way, scientists infer the existence of dark matter based on its gravitational effects on visible matter in the universe. For example, they can observe the way that galaxies rotate and use this information to calculate how much matter must be present to account for the gravitational forces they observe. When they do this, they find that there must be much more matter present than what we can see with our telescopes. This unseen matter is thought to be dark matter.

Overall, the theory of dark matter proposes the existence of a type of matter that is invisible to us, but that has a significant impact on the universe and the way it behaves. It is a crucial part of our current understanding of the universe and continues to be a topic of intense research in astrophysics and cosmology.