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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Using the Earth as a polarized electron source to search for long-range spin-spin interactions
Larry Hunter1, Joel Gordon, Stephen Peck
1Physics Department, Amherst College, Amherst, MA 01002, USA. lrhunter@amherst.edu
Science (New York, N.Y.)
|February 23, 2013
Summary
This study uses Earth
Area of Science:
- Particle Physics
- Geophysics
- Astrophysics
Background:
- Standard Model extensions predict long-range spin-spin interactions.
- Earth's geomagnetic field induces electron polarization within the planet.
- Deep-Earth geophysics and geochemistry data are crucial.
Purpose of the Study:
- Investigate predicted long-range spin-spin interactions.
- Utilize Earth as a polarized spin source.
- Establish bounds on new physics beyond the Standard Model.
Main Methods:
- Map Earth's induced electron polarization using geophysical data.
- Conduct laboratory experiments with spin-polarized electrons and nucleons.
- Analyze interactions between geoelectrons and laboratory spins.
Main Results:
- Comprehensive map of Earth's electron polarization created.
- Bounds established on torsion gravity.
- Constraints placed on long-range spin-spin forces from new bosons or unparticles.
Conclusions:
- Earth can serve as a unique polarized spin source for fundamental physics.
- Experimental results constrain theories beyond the Standard Model.
- Torsion gravity and new force carriers are limited by this approach.
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