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Published on: November 15, 2013
Big Bang Nucleosynthesis Limits and Relic Gravitational-Wave Detection Prospects.
Tina Kahniashvili1,2,3, Emma Clarke1, Jonathan Stepp1
1McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Primordial magnetic fields and turbulent motions may generate stronger gravitational waves than previously thought. This study revisits Big Bang Nucleosynthesis limits, suggesting new detection possibilities for these cosmic signals.
Area of Science:
- Cosmology
- Astrophysics
- Particle Physics
Background:
- Big Bang Nucleosynthesis (BBN) provides constraints on physics beyond the Standard Model.
- Primordial magnetic fields and turbulent motions are hypothesized relics from the early universe.
- Previous BBN limits did not fully account for the decay of turbulent sources.
Purpose of the Study:
- To re-evaluate Big Bang Nucleosynthesis (BBN) constraints on primordial magnetic fields and turbulent motions.
- To investigate the impact of decaying turbulent sources on these constraints.
- To assess the detectability of resulting gravitational wave signals.
Main Methods:
- Theoretical analysis of turbulent decay between generation and BBN.
- Recalculation of BBN constraints incorporating decaying turbulence.
- Estimation of gravitational wave signals from electroweak and quantum chromodynamics energy scales.
Main Results:
- Decaying turbulent sources lead to larger estimates for the gravitational wave signal.
- Updated BBN limits are derived for primordial magnetic fields and turbulence.
- Detection prospects are re-evaluated for various gravitational wave sources.
Conclusions:
- The gravitational wave signal from early universe phenomena may be stronger than previously estimated.
- Space-based interferometers and pulsar timing arrays offer potential detection avenues.
- Further investigation into primordial magnetic fields and turbulence is warranted.
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