Inhomogeneous cosmologies, the Copernican principle and the cosmic microwave background: More on the EGS theorem

Abstract

We discuss inhomogeneous cosmological models which satisfy the Copernican principle. We construct some inhomogeneous cosmological models starting from the ansatz that the all the observers in the models view an isotropic cosmic microwave background. We discuss multi-fluid models, and illustrate how more general inhomogeneous models may be derived, both in General Relativity and in scalar-tensor theories of gravity. Thus we illustrate that the cosmological principle, the assumption that the Universe we live in is spatially homogeneous, does not necessarily follow from the Copernican principle and the high isotropy of the cosmic microwave background.

17 pages; to appear in GRG

References in corpus (5)

• Cosmology and the Fate of Dilatation Symmetry
• Anisotropic cosmologies containing isotropic background radiation
• Shear-free rotating inflation
• The Cosmic Microwave Background and Scalar-Tensor Theories of Gravity
• An inhomogeneous fractal cosmological model

Cited by in corpus (13)

• f(R) Theories Of Gravity
• Relativistic cosmology and large-scale structure
• A general test of the Copernican Principle
• Accelerated expansion from structure formation
• Establishing homogeneity of the universe in the shadow of dark energy
• Light propagation in statistically homogeneous and isotropic dust universes
• Constraints on backreaction in dust universes
• Evaluating backreaction with the peak model of structure formation
• Gauss-Bonnet term corrections in scalar field cosmology
• A covariant treatment of cosmic parallax
• On the relation between the isotropy of the CMB and the geometry of the universe
• Scalar-multi-tensorial equivalence for higher order $f\left(R,{\nabla }_{\mu }R,{\nabla }_{{\mu }_1}{\nabla }_{{\mu }_2}R,...,{\nabla }_{{\mu }_1}...{\nabla }_{{\mu }_n}R\right)$ theories of gravity
• Dominant Energy Condition and dissipative fluids in general relativity