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Updated: May 29, 2026
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
First observational tests of eternal inflation
Stephen M Feeney1, Matthew C Johnson, Daniel J Mortlock
1Department of Physics and Astronomy, University College London, United Kingdom. stephen.feeney.09@ucl.ac.uk
Physical Review Letters
|September 10, 2011
Summary
This study searched for evidence of bubble universe collisions in cosmic microwave background data. Current data do not support the eternal inflation theory
Area of Science:
- Cosmology
- Multiverse Theory
- Cosmic Microwave Background Radiation
Background:
- Eternal inflation theory posits our Universe is one bubble in a multiverse.
- Observational evidence for bubble collisions is currently lacking.
Purpose of the Study:
- To conduct the first observational tests of the eternal inflation scenario.
- To search for signatures of bubble universe collisions in cosmic microwave background (CMB) data.
Main Methods:
- Analysis of cosmic microwave background data from the WMAP satellite.
- Searched for specific cosmological signatures indicative of bubble collisions.
Main Results:
- WMAP 7-year data do not support augmenting the standard cosmological model with bubble collisions.
- Constrained the average number of detectable bubble collisions on the full sky to N(s) < 1.6 at 68% confidence level.
Conclusions:
- The current observational data do not provide evidence for bubble collisions.
- Future data from the Planck satellite may offer more definitive tests of the bubble-collision hypothesis.
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