WebbIn metric formalism, the simplest four-dimensional action in f ( R ) gravity is: A = c 4 16 π G ∫ d 4 x - g f ( R ) + L matter. (1) where g is the determinant of the metric g μ ν , and L matter is the standard perfect fluid matter Lagrangian. Varying the action Equation ( 1) with respect to the metric tensor, we obtain the field equations ... Webb9 jan. 2012 · K. Hinterbichler, Theoretical aspects of massive gravity, arXiv:1105.3735 [ INSPIRE ]. D. Boulware and S. Deser, Can gravitation have a finite range?, Phys. Rev. D 6 (1972) 3368 [ INSPIRE ]. ADS Google Scholar C. de Rham, G. Gabadadze and A.J. Tolley, Resummation of massive gravity, Phys. Rev. Lett. 106 (2011) 231101 [ arXiv:1011.1232] …
Theoretical aspects of massive gravity - NASA/ADS
WebbWe describe the freedom of choosing a square root in massive gravity from algebraic point of view. This contribution is based on the talk given by one of us (AG) ... Hinterbichler, … Webb7 apr. 2024 · 13 April 2024 Astronomy Now. The original Event Horizon Telescope image of the supermassive black hole at the heart of galaxy M87 (left) was the first to capture the shadow of a black hole’s event horizon. Researchers have reconstructed that image using machine learning to sharpen details (right). cry syndrome
On semi-classical topologically massive gravity in three …
Webb1 apr. 2016 · We derive new constraints on massive gravity from unitarity and analyticity of scattering amplitudes. Our results apply to a general effective theory defined by Einstein gravity plus the leading soft diffeomorphism-breaking corrections. We calculate scattering amplitudes for all combinations of tensor, vector, and scalar polarizations. WebbAbstract: General relativity describes gravity in terms of an interacting massless spin-2 field—the graviton. This 100-year-old theory has been spectacularly successful in explaining observations. However, theoretical exploration and the cosmological constant problem motivate the study of alternative theories of gravity. Webb(AG) at the Geometric Foundations of Gravity conference in Tartu in August 2024. 1 Introduction As is well known [1, 2, 3], ghost-free models of massive gravity were … cry tab