# name
Buchdahl Limits Beyond General Relativity

# metadata.dc.description[].value
Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2025, Tutor: Pablo Bueno

# metadata.dc.description.abstract[].value
Buchdahl’s theorem in four dimensions establishes a universal bound on the degree
of compactness of a static star of radius R. The bound is saturated by constant-density stars
with infinite central pressure and in terms of the stars’ Schwarzschild radius reads R ≥ 9
8 rS. We show that the theorem holds for D-dimensional Einstein gravity and that the limit becomes R ≥ h
(D−1)2 4(D−2) i1/(D−3) rS. We show that the bound is modified when Einstein gravity is corrected by a
quadratic higher-curvature term of the Gauss-Bonnet type. In that case, the degree of compactness
can be significantly reduced with respect to the Einsteinian result.

# metadata.dc.title[].value
Buchdahl Limits Beyond General Relativity