NON-SINGULAR RADIATION COSMOLOGICAL MODELS
نویسندگان
چکیده
منابع مشابه
On non-singular inhomogeneous cosmological models
In this talk we would like to review recent results on non-singular cosmological models. It has been recently shown that among stiff perfect fluid inhomogeneous spacetimes the absence of singularities is more common than it was expected in the literature. We would like to generalize these results and apply them to other matter sources.
متن کاملPerturbative analysis of non-singular cosmological model
A stability analysis is made for a non-singular pre-big-bang like cosmological model based on 1-loop corrected string effective action. Its homogeneous and isotropic solution realizes non-singular transition from de Sitter universe to Friedmann-like universe, via super inflation phase. We are interested in whether the non-singular nature of the solution would be stable or not in more general in...
متن کاملUniqueness of the non-singular family and characterisation of cosmological models
We prove that for an orthogonal spacetime metric separable in space and time in comoving coordinates, the requirements of perfect fluid and non-singularity single out the unique family of singularity free cosmological models. Further homogeneous models could only be Bianchi I or FLRW while inhomogeneous ones can be with or without a singularity. PACS Numbers: 04.20Jb, 98.80Dr. 1 E-mail address:...
متن کاملNon-Singular Black Holes, the Cosmological Constant and Asymptotic Safety
Quantum gravitational effects in black hole spacetimes with a cosmological constant Λ are considered. The effective quantum spacetimes for the black holes are constructed by taking into account the renormalization group improvement of classical solutions obtained in the framework of Unimodular Gravity (a theory which is identical to General Relativity at a classical level). This allows us to av...
متن کاملCosmological Models Separable in Non-comoving Coordinates
We study new separable orthogonally transitive abelian G2 on S2 models with two mutually orthogonal integrable Killing vector fields. For this purpose we consider separability of the metric functions in a coordinate system in which the velocity vector field of the perfect fluid does not take its canonical form, providing thereby solutions which are non-separable in comoving coordinates in gener...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Modern Physics Letters A
سال: 2004
ISSN: 0217-7323,1793-6632
DOI: 10.1142/s0217732304013404