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Marginal evidence for cosmic acceleration from Type Ia supernovae
J T Nielsen1, A Guffanti2, S Sarkar1,3
1Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, Copenhagen 2100, Denmark.
Scientific Reports
|October 22, 2016
Summary
The standard model of cosmology assumes accelerating cosmic expansion. However, analysis of a larger Type Ia supernovae dataset suggests the universe's expansion rate may actually be constant.
Area of Science:
- Cosmology
- Astrophysics
- Observational Astronomy
Background:
- The standard model of cosmology posits that the universe's expansion is currently accelerating.
- This inference was originally based on observations of Type Ia supernovae.
- A larger dataset of supernovae is now available for re-evaluation.
Purpose of the Study:
- To rigorously test whether Type Ia supernovae data confirm cosmic acceleration.
- To re-examine the foundational assumptions of the standard cosmological model.
Main Methods:
- Utilizing an expanded database of Type Ia supernovae observations.
- Applying statistical tests to analyze supernova data.
- Accounting for empirical corrections to absolute magnitudes, including light curve variations and dust extinction.
Main Results:
- Despite the larger dataset, the supernova data remain consistent with a constant rate of cosmic expansion.
- The findings challenge the necessity of cosmic acceleration in the standard cosmological model.
Conclusions:
- The current expansion rate of the universe may not be accelerating.
- Further investigation is warranted to reconcile observational data with cosmological models.
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