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Can all cosmological observations be accurately interpreted with a unique geometry?
Pierre Fleury1, Hélène Dupuy, Jean-Philippe Uzan
1Institut d'Astrophysique de Paris, UMR-7095 du CNRS, Université Pierre et Marie Curie, 98 bis boulevard Arago, 75014 Paris, France and Sorbonne Universités, Institut Lagrange de Paris, 98 bis boulevard Arago, 75014 Paris, France.
Physical Review Letters
|September 17, 2013
Summary
Cosmological tensions arise from different measurements of the universe. Using an inhomogeneous Swiss-cheese model reconciles Hubble diagram data with Planck results, suggesting a new interpretation of cosmological observations.
Area of Science:
- Cosmology
- General Relativity
- Astrophysics
Background:
- Current cosmological models face a tension between measurements from the cosmic microwave background (CMB) and baryonic acoustic oscillations (BAO) versus the Hubble diagram.
- These discrepancies suggest potential issues with interpreting cosmological observations across different scales.
Purpose of the Study:
- To investigate the accuracy of using only the perturbed Friedmann-Lemaître geometry for all cosmological observations.
- To explore an alternative model for reconciling the Hubble diagram with Planck results without new physics.
Main Methods:
- Analysis of Planck satellite data and Hubble diagram observations.
- Application of an inhomogeneous "Swiss-cheese" cosmological model.
- Comparison of inferred cosmological parameters (Ω(m0), H(0)) between models.
Main Results:
- The standard Friedmann-Lemaître geometry may not be sufficient for interpreting all cosmological data.
- An inhomogeneous Swiss-cheese model successfully reconciles the Hubble diagram's inferred Ω(m0) with Planck results.
- This reconciliation is achieved without invoking new physics or violating the Copernican principle.
Conclusions:
- The interpretation of cosmological observations might need to account for scale-dependent effects.
- Inhomogeneous models offer a potential solution to the current cosmological tensions.
- The Copernican principle remains valid within this revised framework.
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