Results 61 to 70 of about 32,545 (270)

Conditions for spontaneous homogenization of the Universe [PDF]

, 2010
The present-day Universe appears to be homogeneous on very large scales. Yet when the casual structure of the early Universe is considered, it becomes apparent that the early Universe must have been highly inhomogeneous.
A. Krasiński, A. Linde, A.A. Coley, A.D. Linde, A.G. Riess, C.B. Collins, C.W. Misner, D.J. Eisenstein, D.J. McManus, D.S. Goldwirth, D.S. Goldwirth, D.S. Goldwirth, E. Calzetta, G. Hinshaw, G.F.R. Ellis, H. Elst van, J. Ehlers, J. Plebański, J. Silk, K. Bolejko, K.T. Inoue, K.T. Inoue, Krzysztof Bolejko, M.J. Rees, P. Szekeres, R.M. Wald, S. Perlmutter, S.R. Roy, S.W. Hawking, V. Mukhanov, W.B. Bonnor, W.B. Bonnor, W.R. Stoeger, William R. Stoeger   +33 more
core   +1 more source

Measuring Hubble' constant in our inhomogeneous Universe [PDF]

Monthly Notices of the Royal Astronomical Society, 1996
20 pages (58K), 8 Postscript figures (111K compressed); Submitted to MNRAS. Postscript source available at http://astro.queensu.ca/~dursi/preprints/
Shi, Xiangdong, Widrow, Lawrence M., Dursi, L. Jonathan   +2 more
openaire   +2 more sources

Defect Analysis of the β– to γ–Ga2O3 Phase Transition

Advanced Functional Materials, EarlyView.
The role of defects at all the relevant stages of the β$\beta$‐ to γ$\gamma$‐Ga2O3 polymorph transition is investigated using a multi method approach. The positron annihilation spectroscopy based results show that the defect density decreases after the transition, and that changes in defect configuration within the γ phase occur with increasing ...
Umutcan Bektas, Maciej O. Liedke, Huan Liu, Fabian Ganss, Maik Butterling, Nico Klingner, René Hübner, Ilja Makkonen, Andreas Wagner, Gregor Hlawacek   +9 more
wiley   +1 more source

Signature of f(R) gravity via Lemaître–Tolman–Bondi inhomogeneous perturbations

European Physical Journal C: Particles and Fields
We analyze inhomogeneous cosmological models in the local Universe, described by the Lemaître–Tolman–Bondi (LTB) metric and developed using linear perturbation theory on a homogeneous and isotropic Universe background. Focusing on the different evolution
Tiziano Schiavone, Giovanni Montani
doaj   +1 more source

Formation and Clustering of Primordial Black Holes in Brans-Dicke Theory

Universe, 2020
The formation of primordial black holes in the early universe in the Brans-Dicke scalar-tensor theory of gravity is investigated. Corrections to the threshold value of density perturbations are found.
Victor Berezin, Vyacheslav Dokuchaev, Yury Eroshenko, Alexey Smirnov   +3 more
doaj   +1 more source

Screening vs. gevolution: In chase of a perfect cosmological simulation code

Physics Letters B, 2022
We compare two competing relativistic approaches to the N-body simulation of the Universe large-scale structure. To this end, employing the corresponding alternative computer codes (“gevolution” and “screening”), we conduct a series of cosmological ...
Maxim Eingorn, A. Emrah Yükselci, Alexander Zhuk   +2 more
doaj   +1 more source

Transition between phantom and non-phantom phases with time dependent cosmological constant and Cardy-Verlinde formula

, 2011
We investigate the transition phenomenon of the universe between a phantom and a non-phantom phases. Particular attention is devoted to the case in which the cosmological constant depends on time and is proportional to the square of the Hubble parameter.
Bunch T. S., Carroll S. M., Chen X., Danielsson U. H., Fabris J. C., Filippenko A., Houndjo S., Nojiri S., Ogushi S., Perlmutter S., Petkou A. C., Riess A., S. J. M. Houndjo, Sahni V., Setare M. R., Verlinde E.   +15 more
core   +1 more source

On the Stability of the Einstein Static Universe [PDF]

, 2003
We show using covariant techniques that the Einstein static universe containing a perfect fluid is always neutrally stable against small inhomogeneous vector and tensor perturbations and neutrally stable against adiabatic scalar density inhomogeneities ...
Barrow J D, Barrow J D, Bruni M, Burd A B, Challinor A D, Christos G Tsagas, Dunsby P K S, Eddington A S, Ellis G F R, George F R Ellis, Gibbons G W, Harrison E R, John D Barrow, Landau L, Lifshitz E M, Lukash V, Lukash V, Moschella U, Roy Maartens   +18 more
core   +2 more sources

Photoswitching Conduction in Framework Materials

Advanced Functional Materials, EarlyView.
This mini‐review summarizes recent advances in state‐of‐the‐art proton and electron conduction in framework materials that can be remotely and reversibly switched on and off by light. It discusses the various photoswitching conduction mechanisms and the strategies employed to enhance photoswitched conductivity.
Helmy Pacheco Hernandez, Stefan Hecht, Wolfgang Wenzel, Lars Heinke, Mariana Kozlowska   +4 more
wiley   +1 more source

Viscous attenuation of gravitational waves propagating through an inhomogeneous background

European Physical Journal C: Particles and Fields, 2023
We consider the propagation of gravitational waves in the late-time Universe in the presence of matter distribution inhomogeneities, and we also consider the cosmic fluid to be viscous.
Shashank Shekhar Pandey, Arnab Sarkar, Amna Ali, Archan S. Majumdar   +3 more
doaj   +1 more source