3 papers
gr-qc2026
On a cosmological Oppenheimer-Snyder model: matching McVittie and FLRW spacetimes
Brien C. Nolan
We consider the necessary and sufficient conditions for the smooth matching of an expanding McVittie spacetime and a spatially flat Friedmann-Lema\^ıtre-Robertson-Walker (FLRW) sp…
gr-qc2026
Calculation of a regularized Teukolsky Green function in Schwarzschild spacetime
David Q. Aruquipa, Marc Casals, Brien C. Nolan
We obtain exact expressions for various factors involved in the Hadamard form of the retarded Green function for the (Bardeen-Press-)Teukolsky equation on Schwarzschild spacetime.…
gr-qc2025
Can you fall into a McVittie black hole? Will you survive?
Brien C. Nolan
Yes and maybe. In contrast to the fluid particles of this perfect fluid spacetime which follow non-geodesic world-lines and escape to infinity, we prove that freely-falling test pa…