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New infra-red enhancements in 4-derivative gravity
Alberto Salvio1, Alessandro Strumia1,2, Hardi Veermäe1,3
11Theoretical Physics Department, CERN, Geneva, Switzerland.
The European Physical Journal. C, Particles and Fields
|April 2, 2019
Summary
Four-derivative gravity offers renormalizable quantum gravity with a ghost particle. This study reveals a new
Area of Science:
- Quantum Gravity
- Theoretical Physics
- Particle Physics
Background:
- Renormalizable quantum gravity theories are sought after.
- Four-derivative gravity is a candidate but introduces a ghost particle.
- Understanding the physical implications of this ghost is crucial.
Purpose of the Study:
- To investigate the physical consequences of the ghost particle in four-derivative gravity.
- To compute tree-level scatterings mediated by the ghost.
- To analyze the behavior of super-Planckian scatterings.
Main Methods:
- Tree-level scattering amplitude calculations.
- Analysis of infrared behavior in scattering processes.
- Investigation of energy degradation through radiation.
Main Results:
- A novel power-like infrared enhancement, termed 'ghostrahlung', was identified in ghost-mediated scatterings.
- Super-Planckian scatterings are downgraded to Planckian energies.
- Energy is carried away by radiated gravitons and ghost particles.
Conclusions:
- The ghost particle in four-derivative gravity has observable effects on particle scattering.
- Ghostrahlung represents a unique feature of four-derivative theories.
- The theory provides a mechanism for energy dissipation in high-energy scattering events.
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