5 ms·

But our universe adheres to AdS constraints. As far as we know. When you reach the information density limit in AdS, in our universe you get a black hole.

undersuit 3y ago
A theory used to establish the scene in https://en.wikipedia.org/wiki/Vacuum_Diagrams https://en.wikipedia.org/wiki/Vacuum_Diagrams
- snarkconjecture 3y ago
  The AdS/CFT correspondence was published slightly after that collection. Are you saying Baxter scooped Maldacena?
  - queuebert 3y ago
    While that correspondence proof is relatively new, AdS as a theory is quite old.
    - snarkconjecture 3y ago
      The great-grandparent comment was talking about an "information density limit" and black holes in our universe, so I assumed the referenced sci-fi collection had something to do with holography. I don't know of any particular emphasis on AdS in that context before 1997. Elaborate? Obviously you can stick GR in AdS, but AFAIK nothing about that would've seemed interesting with regards to holography before Maldacena, let alone plausibly providing inspiration to a fiction author. To be less roundabout than my previous comment: I think Baxter may have been inspired by the holographic principle in general, but I doubt AdS crossed his mind at all when he was writing these stories in the 80s and early 90s. (EDIT: or maybe Baxter was thinking about AdS but not about holography. I haven't read his work.)
      - undersuit 3y ago
        Vacuum Diagrams is a collection of short stories Stephen Baxter has written well before 1997, but the published collection in 1997 included new intertwining narrative stories about an AI named EVE to bind them together. EVE is an AI in a black hole? On the edge of one? Stephen Baxter is known for sch-fi so hard it'll cut you. He may have just accidentally come up with similar concepts during the same year.
codethief 3y ago
> But our universe adheres to AdS constraints. As far as we know. No, as far as we know, it doesn't since the cosmological constant is slightly positive, so the universe would best be described by de Sitter spacetime, not anti-de Sitter. https://en.m.wikipedia.org/wiki/Anti-de_Sitter_space https://en.m.wikipedia.org/wiki/Anti-de_Sitter_space
empath-nirvana 3y ago
Our universe is definitely not an ADS. Think of the spaces in ADS/CFT as mathematical spaces, not physical spaces. It lets you take a model constructed in one space, translate it into another space, perform some calculations there that might be simpler and then translate them back.

undersuit 3y ago

A theory used to establish the scene in https://en.wikipedia.org/wiki/Vacuum_Diagrams https://en.wikipedia.org/wiki/Vacuum_Diagrams

snarkconjecture 3y ago
The AdS/CFT correspondence was published slightly after that collection. Are you saying Baxter scooped Maldacena?
- queuebert 3y ago
  While that correspondence proof is relatively new, AdS as a theory is quite old.
  - snarkconjecture 3y ago
    The great-grandparent comment was talking about an "information density limit" and black holes in our universe, so I assumed the referenced sci-fi collection had something to do with holography. I don't know of any particular emphasis on AdS in that context before 1997. Elaborate? Obviously you can stick GR in AdS, but AFAIK nothing about that would've seemed interesting with regards to holography before Maldacena, let alone plausibly providing inspiration to a fiction author. To be less roundabout than my previous comment: I think Baxter may have been inspired by the holographic principle in general, but I doubt AdS crossed his mind at all when he was writing these stories in the 80s and early 90s. (EDIT: or maybe Baxter was thinking about AdS but not about holography. I haven't read his work.)
    - undersuit 3y ago
      Vacuum Diagrams is a collection of short stories Stephen Baxter has written well before 1997, but the published collection in 1997 included new intertwining narrative stories about an AI named EVE to bind them together. EVE is an AI in a black hole? On the edge of one? Stephen Baxter is known for sch-fi so hard it'll cut you. He may have just accidentally come up with similar concepts during the same year.

codethief 3y ago

> But our universe adheres to AdS constraints. As far as we know. No, as far as we know, it doesn't since the cosmological constant is slightly positive, so the universe would best be described by de Sitter spacetime, not anti-de Sitter. https://en.m.wikipedia.org/wiki/Anti-de_Sitter_space https://en.m.wikipedia.org/wiki/Anti-de_Sitter_space

empath-nirvana 3y ago

Our universe is definitely not an ADS. Think of the spaces in ADS/CFT as mathematical spaces, not physical spaces. It lets you take a model constructed in one space, translate it into another space, perform some calculations there that might be simpler and then translate them back.