Black hole soft hair, the edge of the universe, and closed timelike curves
timandersen.substack.com
In this week’s newsletter I’m bringing together a few ideas that are interesting me: stereographic projection (and conformal mappings in general), boundaries, supertranslation symmetries, and closed timelike curves. Mostly I’ve been thinking about asymptotically flat spacetime, that concept that as you go further away from a massive object, such as a black hole, spacetime becomes more flat. Flat spacetime is much easier to understand and work with than curved spacetime because it has symmetries. Curved spacetime near a black hole, on the other hand, has few symmetries, not easy to grasp.
Black hole soft hair, the edge of the universe, and closed timelike curves
Black hole soft hair, the edge of the…
Black hole soft hair, the edge of the universe, and closed timelike curves
In this week’s newsletter I’m bringing together a few ideas that are interesting me: stereographic projection (and conformal mappings in general), boundaries, supertranslation symmetries, and closed timelike curves. Mostly I’ve been thinking about asymptotically flat spacetime, that concept that as you go further away from a massive object, such as a black hole, spacetime becomes more flat. Flat spacetime is much easier to understand and work with than curved spacetime because it has symmetries. Curved spacetime near a black hole, on the other hand, has few symmetries, not easy to grasp.