Results 1 to 10 of about 60,199 (278)

Unravelling cosmological perturbations [PDF]

Physics Letters B, 2018
We explain in detail the quantum-to-classical transition for the cosmological perturbations using only the standard rules of quantum mechanics: the Schrödinger equation and Born's rule applied to a subsystem. We show that the conditioned, i.e. intrinsic,
Timothy J. Hollowood
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Cosmological perturbations [PDF]

Physics Reports, 2009
We review the study of inhomogeneous perturbations about a homogeneous and isotropic background cosmology. We adopt a coordinate based approach, but give geometrical interpretations of metric perturbations in terms of the expansion, shear and curvature ...
Malik, Karim A., Wands, David
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Intrinsic Entropy of Squeezed Quantum Fields and Nonequilibrium Quantum Dynamics of Cosmological Perturbations [PDF]

Entropy, 2021
Density contrasts in the universe are governed by scalar cosmological perturbations which, when expressed in terms of gauge-invariant variables, contain a classical component from scalar metric perturbations and a quantum component from inflaton field ...
Jen-Tsung Hsiang, Bei-Lok Hu
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Brane World Cosmological Perturbations [PDF]

Physical Review D, 2004
We consider a brane world and its gravitational linear perturbations. We present a general solution of the perturbations in the bulk and find the complete perturbed junction conditions for generic brane dynamics. We also prove that (spin 2) gravitational
Adenauer G. Casali, Bin Wang, Bin Wang, Bin Wang, Bin Wang, Bin Wang, C. Csáki, C. Csáki, C. Lanczos, C. Lanczos, D.J. Chung, D.J. Chung, D.S. Goldwirth, David Langlois, Dmitry S. Gorbunov, E. Abdalla, E. Abdalla, E. Witten, Elcio Abdalla, F. Quevedo, G. Darmois, G.F. Giudice, H. Ishihara, Hideo Kodama, K. Koyama, K. Koyama, L. Randall, L. Randall, M. Gasperini, N. Deruelle, P. Binetruy, P. Horava, R. Caldwell, R. Easther, Roy Maartens, Shin’ichi Nojiri, Shin’ichi Nojiri, T. Hiramatsu, W. Israel, W. Israel   +39 more
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Cosmological Perturbations [PDF]

, 2002
The aim of these lecture notes is to familiarize graduate students and beginning postgraduates with the basic ideas of linear cosmological perturbation theory and of structure formation scenarios.
Tsagas, Christos G.
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Cosmological Backreaction from Perturbations [PDF]

Journal of Cosmology and Astroparticle Physics, 2007
We reformulate the averaged Einstein equations in a form suitable for use with Newtonian gauge linear perturbation theory and track the size of the modifications to standard Robertson-Walker evolution on the largest scales as a function of redshift for ...
Alnes H, Behrend J, Behrend J Nachtmann O, Biswas T Mansouri R Notari A, Brouzakis N, Buchert T, Buchert T, Buchert T, Doran M, Ellis G F R, Enqvist K, Enqvist K, Futamase T, Georg Robbers, Geshnizjani G, Gourgoulhon E, Hossain G M, Iain A Brown, Ishak M Richardson J Whittington D Garred D, Ishibashi A, Juliane Behrend, Khosravi S Kourkchi E Mansouri R, Kolb E W Matarrese S Notari A Riotto A, Langlois D, Langlois D, Larena J Buchert T, Larena J Buchert T Alimi J-M, Li N Schwarz D J, Li N Schwarz D J, Linder E V, Lu T H-C, Lyth D H, Marra V Kolb E W Matarrese S Riotto A, Martineau P Brandenberger R, Mattsson T Ronkainen M, McClure M L Hellaby C, Parry M F, Rasanen S, Rasanen S, Rasanen S, Riess A G, Vanderveld R A Flanagan E E Wasserman I, Wald R M, Wiltshire D L, Wiltshire D L, York J W, Zalaletdinov R   +46 more
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Hamiltonian Cosmological Perturbation Theory [PDF]

Physics Letters B, 2005
The Hamiltonian approach to cosmological perturbations in general relativity in finite space-time is developed, where a cosmological scale factor is identified with spatial averaging the metric determinant logarithm.
A.F. Zakharov, Arnowitt, B.M. Barbashov, Bajan, Bardeen, Behnke, Blaschke, Dirac, Dirac, Esposito-Farese, Fock, Kuchar, Lifshitz, Mukhanov, Pawlowski, Perlmutter, Riess, Riess, V.A. Zinchuk, V.N. Pervushin, Weinberg, York, Zelmanov, Zelmanov   +23 more
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The MESS of cosmological perturbations

Physics Letters B, 2018
We introduce two new effective quantities for the study of comoving curvature perturbations ζ: the space dependent effective sound speed (SESS) and the momentum dependent effective sound speed (MESS).
Antonio Enea Romano, Sergio A. Vallejo Peña   +1 more
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Magnetized cosmological perturbations [PDF]

Physical Review D, 2000
A large-scale cosmic magnetic field affects not only the growth of density perturbations, but also rotational instabilities and anisotropic deformation in the density distribution.
A. Davis, A. Davis, A. Kosowsky, A.D. Challinor, A.D. Dolgov, A.M. Wolfe, B. Ratra, C.G. Tsagas, C.G. Tsagas, Christos G. Tsagas, D. Grasso, D.D. Harari, D.T. Son, E. Battaner, E. Kim, E.A. Calzetta, E.R. Harrison, E.S. Scannapieco, G.F.R. Ellis, G.F.R. Ellis, G.F.R. Ellis, H. Kodama, I. Wasserman, J. Adams, J.D. Barrow, J.D. Barrow, K. Enqvist, K. Jedamzik, K. Subramanian, K. Subramanian, M. Abramowitz, M. Bruni, M. Gasperini, M.S. Turner, P.P. Kronberg, P.P. Kronberg, R. Durrer, R. Maartens, R. Maartens, R. Maartens, R. Maartens, R. Maartens, R.M. Kulsrud, Roy Maartens, S.W. Hawking, T. Padmanabhan, T. Vachaspati, T.V. Ruzmaikina, V.F. Mukhanov, Ya. B. Zeldovich   +49 more
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Brane cosmological perturbations [PDF]

Physical Review D, 2000
We address the question of cosmological perturbations in the context of brane cosmology, where our Universe is a three-brane where matter is confined, whereas gravity lives in a higher dimensional spacetime. The equations governing the bulk perturbations
A. Ishibashi, A. Lukas, C. Charmousis, C. Csaki, C. Csáki, D. Ida, David Langlois, E. Flanagan, E.J. Squires, G.W. Gibbons, H. Kodama, H. Kodama, H. Stoica, H.A. Chamblin, H.B. Kim, I. Antoniadis, J. Lesgourgues, J.M. Bardeen, J.M. Cline, L. Randall, M. Gogberashvili, M. Gogberashvili, M. Visser, N. Arkani-Hamed, N. Arkani-Hamed, N. Deruelle, N. Kaloper, P. Binétruy, P. Binétruy, P. Kanti, P. Kraus, R. Maartens, R. Maartens, R.M. Wald, S. Mukohyama, T. Nihei, T. Shiromizu, V.A. Rubakov, V.F. Mukhanov, W. Israel   +39 more
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