Results 51 to 60 of about 1,881,508 (108)
Quantum Gravity: Motivations and Alternatives [PDF]
The mutual conceptual incompatibility between General Relativity and Quantum Mechanics / Quantum Field Theory is generally seen as the most essential motivation for the development of a theory of Quantum Gravity.
Hedrich, Reiner
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Philosophers of physics and physicists have long been intrigued by the analogies and disanalogies between gravitational theories and (Yang-Mills-type) gauge theories.
Teh, Nicholas
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Consistent modified gravity: dark energy, acceleration and the absence of cosmic doomsday
We discuss modified gravity which includes negative and positive powers of curvature and provides gravitational dark energy. It is shown that in GR plus a term containing a negative power of curvature, cosmic speed-up may be achieved while the effective ...
Abdalla, MCB +2 more
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Observational tests of modified gravity
Modified gravity theories have richer observational consequences for large-scale structure than conventional dark energy models, in that different observables are not described by a single growth factor even in the linear regime. We examine the relationships between perturbations in the metric potentials, density and velocity fields, and discuss ...
Jain, Bhuvnesh, Zhang, Pengjie
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COSMIC ACCELERATION AND MODIFIED GRAVITY
I briefly discuss some attempts to construct a consistent modification to general relativity (GR) that might explain the observed late-time acceleration of the Universe and provide an alternative to dark energy. I describe the issues facing extensions to GR, illustrate these with a specific example, and discuss the resulting observational and ...
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Cosmological hints of modified gravity?
The recent measurements of Cosmic Microwave Background temperature and polarization anisotropies made by the Planck satellite have provided impressive confirmation of the $Λ$CDM cosmological model. However interesting hints of slight deviations from $Λ$CDM have been found, including a $95 \%$ c.l. preference for a "modified gravity" structure formation
DI VALENTINO, ELEONORA +2 more
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A viable model for modified gravity [PDF]
We propose a model for modified gravity that meets the conditions of viability. The model has stable constant curvature solution and for an special case contains flat space time solution. The model also leads to matter stability under small perturbations of scalar curvature.
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Review of Emergent Gravity [PDF]
openThe idea that gravity may not be a fundamental interaction but rather an emergent phenomenon has gained increasing attention in recent decades. Building on the thermodynamical properties of spacetime horizons, various approaches suggest that Einstein’
GERVANI, LORENZO
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GOCE data evidence underplating beneath the Paraná basin
The Paraná basin in the stable South American Platform accumulated a thick sediment layer during the Paleozoic, with more than 3500 m thickness. In Early Cretaceous the same area experienced a flood basalt volcanism which produced a LIP-(Large Igneous ...
MARIANI, PATRIZIA +2 more
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Stellar oscillations in modified gravity [PDF]
Starting from the equations of modified gravity hydrodynamics, we derive the equ tions of motion governing linear, adiabatic, radial perturbations of stars in scalar-tensor theories. There are two new features: first, the eigenvalue equation for the period of stellar oscillations is modified such that the eigenfrequencies are always larger than ...
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