Infinite Space-time into finite region, Penrose diagrams explained

[@sebastiandierks7919]

Thank you, nicely done for a very complicated topic! I liked especiallly the nice graphics on screen. Maybe to offer some constructive criticism, I think there were some minor errors in the script for the voice over, like "i and z axes" instead of y and z, Kruskal and Sean (Carroll) were pronounced funnily, and "tan function" instead of inverse tangent (was correct on screen though). All in all very good though, as I said.

[@quantverse1294]

Thank you, Sebastian, for your kind feedback. We will definitely work on getting the voice-over accurate in the next videos :)

[@lauriestanton2201]

Why is light moving at specifically 45°? Is this only for the purposes of the Penrose Diagram?

[@lauriestanton2201]

I got it, because lines on the graph are showing movement through space AND time, and since light travels at the lightday interval. If it traveled faster, its line would be at greater an angle. Anything moving slower is at an angle less than 45°.

[@quantverse1294]

@@lauriestanton2201 You are right.

[@quantverse1294]

Please comment your opinion on this video.

[@RTort]

Really cool.

[@michael-jamesb.weaver9775]

Background music is too distracting.

[@RaviPatel-iq3ce]

I don’t understand this thing with infinite space and time. How is space infinite if we can map and predict the boundaries. How is time infinite when it had a beginning. If you take this into account, how can you traverse the Penrose diagram?

[@quantverse1294]

Time and space is infinite in flat Minkowski space-time. In expanding universe, time would have a beginning. Penrose diagram for a Minkowski or expanding universe is different.

[@RaviPatel-iq3ce]

@@quantverse1294 but we don’t live in an infinite universe.

[@quantverse1294]

@@RaviPatel-iq3ce@RaviPatel-iq3ce Penrose diagrams handle both finite and infinite universes. It is just a conformal mapping, which is a mathematical function. There are Penrose diagrams for the finite universe as well; the idea is the same.