Results 41 to 50 of about 70,487 (262)
added references; made some clarifications; 8 ...
Dimitrijevic, Ivan +3 more
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The P-V phase transition of the FRW universe
We define thermodynamic pressure P by work density W as the conjugate quantity of thermodynamic volume V from field equation. We derive the equations of state P=P(V, T) for the Friedmann–Robertson–Walker (FRW) universe in Einstein gravity and a modified ...
Shi-Bei Kong +4 more
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GRAVITY FROM A MODIFIED COMMUTATOR [PDF]
We show that a suitably chosen position-momentum commutator can elegantly describe many features of gravity, including the IR/UV correspondence and dimensional reduction ("holography"). Using the most simplistic example based on dimensional analysis of black holes, we construct a commutator which qualitatively exhibits these novel properties of ...
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Chaos in a Magnetized Modified Gravity Schwarzschild Spacetime
Based on the scalar–tensor–vector modified gravitational theory, a modified gravity Schwarzschild black hole solution has been given in the existing literature.
Daqi Yang +5 more
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Cosmological tests of modified gravity [PDF]
82 pages, 28 figures. This review is partly based on arXiv:1304.0601, arXiv:1305.0279 and arXiv:1503.06673.
openaire +5 more sources
Swampland and screened modified gravity [PDF]
We consider the implications of the swampland conjectures on scalar-tensor theories defined in the Einstein frame in which the scalar interaction is screened. We show that chameleon models are not in the swampland provided the coupling to matter is larger than unity and the mass of the scalar field is much larger than the Hubble rate.
Brax, P., van de Bruck, C., Davis, A.-C.
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Charged gravastars in modified gravity [PDF]
In this paper, we investigate the effects of electromagnetic field on the isotropic spherical gravastar models in metric $f(R,T)$ gravity. For this purpose, we have explored singularity-free exact models of relativistic spheres with a specific equation of state.
Yousaf, Z. +3 more
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Maxwell-modified metric affine gravity
We present a gauge formulation of the special affine algebra extended to include an antisymmetric tensorial generator belonging to the tensor representation of the special linear group.
Oktay Cebecioğlu, Salih Kibaroğlu
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Matter Instability in Theories with Modified Induced Gravity
Matter stability is a necessary condition to have a cosmologically viable model. Modified gravity in the spirit of f(R) theories suffers from matter instability in some subdomains of the model parameter space.
Kourosh Nozari, Faeze Kiani
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