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Updated: May 18, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Clustering fossils from the early universe
Donghui Jeong1, Marc Kamionkowski
1Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21210, USA.
Physical Review Letters
|September 26, 2012
Summary
This study introduces methods to detect imprints from primordial scalar, vector, and tensor fields in galaxy surveys. These methods can reveal new physics beyond the standard inflationary model.
Area of Science:
- Cosmology
- Astrophysics
- Particle Physics
Background:
- Inflationary theories predict new scalar, vector, or tensor fields.
- These fields can influence the generation of primordial density perturbations.
Purpose of the Study:
- Develop methods to search galaxy or 21-cm surveys for imprints of primordial fields.
- Investigate the impact of these fields on statistical isotropy and correlation functions.
Main Methods:
- Analyze departures from statistical isotropy in two-point correlation functions.
- Examine nontrivial four-point correlation functions (trispectra) in Fourier space.
- Decompose observed signals into scalar, vector, and tensor components.
Main Results:
- Derived optimal estimators for scalar, vector, and tensor components.
- Quantified the dependence of detection sensitivity on galaxy survey parameters.
- Presented new probes for parity-violating early-Universe physics.
Conclusions:
- Galaxy and 21-cm surveys can be used to search for new primordial fields.
- The framework allows for the decomposition and identification of different field types.
- This research opens avenues for exploring early Universe physics and parity violation.
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