Related Experiment Videos
Cosmological constraints on bulk neutrinos
Kevork N Abazajian1, George M Fuller, Mitesh Patel
1Department of Physics, University of California, San Diego, La Jolla, California 92093-0319, USA. aba@fna1.gov
Physical Review Letters
|March 14, 2003
Summary
Models with extra space-like dimensions impact cosmology if the largest dimension exceeds 1 femtometer. These models provide stronger constraints on new physics than current laboratory or graviton overproduction limits.
Area of Science:
- Cosmology
- Particle Physics
- Theoretical Physics
Background:
- Neutrinos are fundamental particles that interact weakly.
- Extra space-like dimensions are a theoretical concept in some physics models.
- The size of extra dimensions can influence cosmological observations.
Purpose of the Study:
- To investigate the cosmological effects of neutrinos in extra space-like dimensions.
- To determine constraints on the size of extra dimensions based on cosmological data.
Main Methods:
- Analyzing effects on cosmic microwave background anisotropies.
- Examining impacts on big bang nucleosynthesis and light element photoproduction.
- Considering diffuse photon backgrounds and structure formation.
Main Results:
- Significant cosmological effects arise if the largest extra dimension size (R) is greater than approximately 1 femtometer.
- Constraints derived from cosmological effects can be more stringent than existing limits.
- These include constraints from bulk graviton overproduction and laboratory experiments.
Conclusions:
- Models with large extra dimensions (R > 1 fm) inhabited by neutrinos have observable cosmological consequences.
- Cosmological observations provide powerful constraints on theories with extra dimensions.
- These constraints can surpass those from other methods, offering new avenues for physics beyond the Standard Model.