Physicist explains Large Hadron Collider discoveries | Lisa Randall and Lex Fridman

TL;DR

The Milky Way galaxy has a flat disc shape, while dark matter tends to be distributed spherically, although there may be some flat disc components.

Transcript

can you just clarify just fascinating uh the shape of things so the shape of the Milky Ways of the observable stuff is mostly flat and then you said Dark Matter tends to be spherical but a subset of that might be a flat disc so you want to hear about the shape of things yeah yes please so structure formed early on and now our structure that we live... Read More

Key Insights

• 🫥 The Milky Way galaxy consists of a visible flat disc, while dark matter is spherically distributed.
• 🕶️ Dark matter does not collapse due to its inability to radiate like ordinary matter.
• 🥏 Some evidence suggests the presence of disc-shaped components within dark matter.
• 🕶️ There is still uncertainty about the composition and nature of dark matter.
• 🕶️ Various particles, such as axions, are proposed as potential candidates for dark matter.
• 🫥 Detection of dark matter is primarily based on its gravitational effects on visible matter.
• 🤞 The Large Hadron Collider (LHC) was initially hoped to discover dark matter, but other detection methods, such as underground detectors, are being pursued.
• 💄 The discovery of the Higgs boson at the LHC was a significant achievement, but also a cautionary tale about making assumptions before finding experimental evidence.

Questions & Answers

Q: What is the shape of the visible portion of the Milky Way galaxy?

The visible portion of the Milky Way galaxy has a flat disc shape, where stars and light are concentrated.

Q: How is dark matter distributed in the Milky Way?

Dark matter is believed to be spherically distributed in the Milky Way, with a large amount present throughout, but not necessarily within the disc.

Q: Can dark matter collapse like ordinary matter?

Dark matter does not collapse because it lacks the ability to radiate like ordinary matter, which causes it to maintain its shape, attributed to conservation of angular momentum.

Q: Are there any components of dark matter that exhibit a disc shape?

There is some evidence of certain densities of dark matter exhibiting a disc shape, although this is not yet proven and is still a subject of research.

Summary & Key Takeaways

• The visible portion of the Milky Way galaxy is mostly flat, consisting of stars and light within a disc-shaped structure.

• Dark matter, on the other hand, is believed to be spherically distributed, although there is evidence of some flat disc components.

• Dark matter does not collapse due to its inability to radiate like ordinary matter, which is attributed to conservation of angular momentum.