Results 41 to 50 of about 6,695,532 (296)
Cosmology of the Jackiw–Teitelboim Model [PDF]
General Relativity and Gravitation, 2002 We investigate the cosmology of the two-dimensional Jackiw-Teitelboim model. Since the matter coupling is not defined uniquely, we consider two possible choices. The dilaton field plays an important role in the discussion of the properties of the solutions. In particular, the possibility of universes having a finite initial size emerges.
CADONI, MARIANO, MIGNEMI, SALVATORE
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The topology of general cosmological models*
Classical and Quantum Gravity, 2022 Abstract Is the Universe finite or infinite, and what shape does it have? These fundamental questions, of which relatively little is known, are typically studied within the context of the standard model of cosmology where the Universe is assumed to be homogeneous and isotropic.
Gregory J Galloway +2 more
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Primordial black holes in non-linear perturbation theory [PDF]
, 2009 PhDThe thesis begins with a study of the origin of non-linear cosmological fluctuations. In particular, a class of models of multiple field inflation are considered, with specific reference to those cases in which the non-Gaussian correlation functions
Hidalgo-Cuellar, Juan Carlos
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Neutrinos in Cosmological Models [PDF]
Progress of Theoretical Physics, 1980 Observations show that the Universe is very nearly homogeneous and isotropic on a large scale. It follows, that on a large scale, the Universe may be approximately described by one of the Robertson-Walker models. These models have the property o£ possessing exact spatial homogeneity and isotropy about each event.
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ANALOGUE MODELS FOR FRW COSMOLOGIES [PDF]
International Journal of Modern Physics D, 2003 It is by now well known that various condensed matter systems may be used to mimic many of the kinematic aspects of general relativity, and in particular of curved-spacetime quantum field theory. In this essay we will take a look at what would be needed to mimic a cosmological spacetime — to be precise a spatially flat FRW cosmology — in one of these ...
CARLOS BARCELO +2 more
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A Bias-free Cosmological Analysis with Quasars Alleviating H 0 Tension
The Astrophysical Journal Supplement Series, 2023 Cosmological models and their parameters are widely debated because of theoretical and observational mismatches of the standard cosmological model, especially the current discrepancy between the value of the Hubble constant, H _0 , obtained by Type Ia ...
Aleksander Łukasz Lenart +4 more
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Cosmological Model with Ω M -Dependent Cosmological Constant [PDF]
General Relativity and Gravitation, 2003 10 ...
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Rip Cosmology via Inhomogeneous Fluid
Galaxies, 2013 The conditions for the appearance of the Little Rip, Pseudo Rip and Quasi Rip universes in the terms of the parameters in the equation of state of some dark fluid are investigated. Several examples of the Rip cosmologies are investigated.
Alexander V. Timoshkin +2 more
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Local Solvent Ordering Drives Supramolecular Chirality Inversion
Advanced Science, EarlyView.Local solvent organization is shown to govern supramolecular chirality by selecting distinct chiral assembly pathways. A subtle change in water‐DMSO composition reverses the helical sense of a chiral perylene bisimide, while heating induces an irreversible thermal inversion to a more stable enantiomorph.
Triza Pal +4 more
wiley +1 more source