Beyond Einstein's General Relativity

Abstract

Modern astrophysical and cosmological models are plagued with two severe theoretical difficulties, namely, the dark energy and the dark matter problems. Relative to the former, high-precision observational data have confirmed with startling evidence that the Universe is undergoing a phase of accelerated expansion. This phase, one of the most important and challenging current problems in cosmology, represents a new imbalance in the governing gravitational equations. Several candidates, responsible for this expansion, have been proposed in the literature, in particular, dark energy models and modified gravity, amongst others. Outstanding questions are related to the nature of this so-called "dark energy" that is driving the acceleration of the universe, and whether it is due to the vacuum energy or a dynamical field. On the other hand, the late-time cosmic acceleration may be due to modifications of General Relativity, which introduce new degrees of freedom to the gravitational sector itself. We analyze some of the modified theories of gravity that address these intriguing and exciting problems facing modern physics, and explore the foundations of gravitation theory, essential for the construction of modified theories of gravity.

16 pages. Proceedings based on a plenary talk delivered at the Spanish Relativity Meeting 2014 (ERE-2014). V2: references added, typos corrected. V3: reference added

References in corpus (37)

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• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Dynamics of dark energy
• f(R) Theories Of Gravity
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• f(R) theories
• 4D Gravity on a Brane in 5D Minkowski Space
• Extended Theories of Gravity
• Quintessence, Cosmic Coincidence, and the Cosmological Constant
• Black Holes: Complementarity or Firewalls?
• Cool horizons for entangled black holes
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• Cosmology and fundamental physics with the Euclid satellite
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• Brane-world gravity
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• f(R,L_m) gravity
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Cited by in corpus (8)

• A Generalization to the Rastall Theory and Cosmic Eras
• Static traversable wormholes in Lyra manifold
• Dynamical reconstruction of the $\Lambda$CDM model in scalar-tensor $f(R,T)$ gravity
• Curvature-matter couplings in modified gravity: from linear models to conformally invariant theories
• Null Fluid collapse in Rastall theory of gravity
• Thermodynamic analysis of gravitational field equations in Lyra manifold
• Thermodynamical study of FRW universe in Quasi-Topological Theory
• Tracing Signatures of Modified Gravity in Redshift-Space Galaxy Bispectrum Multipoles: Prospects for Euclid