What is Newman Penrose Formalism?

  • Thread starter Thread starter yicong2011
  • Start date Start date
  • Tags Tags
    Penrose
yicong2011
Messages
75
Reaction score
0
What is Newman Penrose Formalism?

Are there any easy-to-read references? I find their original work on N-P Formalism, but only find it is a bit difficult for me...

Thank you.
 
Physics news on Phys.org
The N-P Formalism is a formulation of Einstein's equations based on a null tetrad, mainly useful for discussing radiation problems. What makes it seem so complicated is that instead of index notation, they assign a different Greek letter to each one of the Ricci rotation coeficients.
 
Last edited by a moderator:
Thank you. But I do not find anything about NP Formalism in Ryder's Book...
 
yicong2011 said:
Thank you. But I do not find anything about NP Formalism in Ryder's Book...

Look in section 7.8 Rotating Black Holes: Kerr Solution.
 
OK, so this has bugged me for a while about the equivalence principle and the black hole information paradox. If black holes "evaporate" via Hawking radiation, then they cannot exist forever. So, from my external perspective, watching the person fall in, they slow down, freeze, and redshift to "nothing," but never cross the event horizon. Does the equivalence principle say my perspective is valid? If it does, is it possible that that person really never crossed the event horizon? The...
In this video I can see a person walking around lines of curvature on a sphere with an arrow strapped to his waist. His task is to keep the arrow pointed in the same direction How does he do this ? Does he use a reference point like the stars? (that only move very slowly) If that is how he keeps the arrow pointing in the same direction, is that equivalent to saying that he orients the arrow wrt the 3d space that the sphere is embedded in? So ,although one refers to intrinsic curvature...
So, to calculate a proper time of a worldline in SR using an inertial frame is quite easy. But I struggled a bit using a "rotating frame metric" and now I'm not sure whether I'll do it right. Couls someone point me in the right direction? "What have you tried?" Well, trying to help truly absolute layppl with some variation of a "Circular Twin Paradox" not using an inertial frame of reference for whatevere reason. I thought it would be a bit of a challenge so I made a derivation or...
Back
Top