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THE COSMOLOGICAL SPACETIME [PDF]
International Journal of Modern Physics D, 2009 We present here the transformations required to recast the Robertson–Walker metric and Friedmann–Robertson–Walker equations in terms of observer-dependent coordinates for several commonly assumed cosmologies. The overriding motivation is the derivation of explicit expressions for the radius Rh of our cosmic horizon in terms of measurable quantities ...
Melia, Fulvio, Abdelqader, Majd
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Physical Review D, 1995 An exploratory study of the cosmology of moduli in string theory. Moduli are argued to be natural inflaton fields and lead to a robust inflationary cosmology in which inflation takes place at the top of domain walls. The amplitude of microwave background fluctuations constrains the dynamics responsible for inflation to take place at a higher scale than
Banks, T. +4 more
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DECOHERENCE IN QUANTUM COSMOLOGY AND THE COSMOLOGICAL CONSTANT [PDF]
Modern Physics Letters A, 2013 We discuss a spacetime having the topology of S3×ℝ but with a different smoothness structure. The initial state of the cosmos in our model is identified with a wildly embedded 3-sphere (or a fractal space). In previous work we showed that a wild embedding is obtained by a quantization of a usual (or tame) embedding.
Asselmeyer-Maluga, T., Krol, J.
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Evolution of cosmological horizons of wormhole cosmology [PDF]
International Journal of Modern Physics D, 2020 Recently, we solved Einstein’s field equations to obtain the exact solution of the cosmological model with the Morris–Thorne-type wormhole. We found the apparent horizons and analyzed their geometric natures, including the causal structures. We also derived the Hawking temperature near the apparent cosmological horizon.
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Precision cosmology, Accuracy cosmology and Statistical cosmology [PDF]
Proceedings of the International Astronomical Union, 2014 AbstractThe avalanche of data over the past 10-20 years has propelled cosmology into the “precision era”. The next challenge cosmology has to meet is to enter the era of accuracy. Because of the intrinsic nature of studying the Cosmos and the sheer amount of data available now and coming soon, the only way to meet this challenge is by developing ...
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COSMOLOGICAL PERTURBATIONS IN RENORMALIZATION GROUP DERIVED COSMOLOGIES [PDF]
International Journal of Modern Physics D, 2004 A linear cosmological perturbation theory of an almost homogeneous and isotropic perfect fluid Universe with dynamically evolving Newton constant G and cosmological constant Λ is presented. A gauge invariant formalism is developed by means of the covariant approach, and the acoustic propagation equations governing the evolution of the comoving ...
Bonanno, A., Reuter, M.
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The Existence and Effect of Dark Energy Redshift on Cosmological Age
Advances in Astronomy, 2020 A derivation of Cosmological Age explicitly constrained by Cosmic Microwave Background Radiation (CMBR) is presented, demonstrating that the correct value of Cosmological Age is equal to the Hubble Age. It is shown that utilizing “z = 0” for Cosmological
Riccardo C. Storti
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Hearing gravity from the cosmos: GWTC-2 probes general relativity at cosmological scales
Physics Letters B, 2021 Gravitational-wave (GW) catalogs are rapidly increasing in number, allowing for statistical analyses of the population of compact binaries. Nonetheless, GW inference of cosmology has typically relied on additional electromagnetic counterparts or galaxy ...
Jose María Ezquiaga
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Cosmological quasiparticles and the cosmological collider
Physical Review D31 pages, 11 ...
Jay Hubisz +3 more
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