Astrophysical bounds on photons escaping into extra dimensions

Area of Science:

• Theoretical physics
• Particle physics
• Cosmology

Background:

• Extra-dimensional models with warped metrics propose gravity can localize photons on a brane.
• A key feature is the potential for photons to escape into extra dimensions.
• This phenomenon motivates precision ortho-positronium decay experiments.

Purpose of the Study:

• To investigate the implications of photons escaping into extra dimensions within a specific theoretical framework.
• To explore the metastability of photons in plasma under these conditions.
• To derive new constraints on extra-dimensional models.

Main Methods:

• Analysis of extra-dimensional models with a warped metric and a single brane.
• Theoretical investigation of photon behavior in plasma within this framework.
• Derivation of model parameter bounds based on astrophysical phenomena.

Main Results:

• Photons in plasma are predicted to be metastable in these extra-dimensional models.
• This metastability has significant implications for astrophysical cooling processes.
• New bounds derived for the model parameter far exceed the reach of current ortho-positronium experiments.

Conclusions:

• The metastability of photons in plasma provides a powerful new avenue for constraining extra-dimensional theories.
• Astrophysical observations offer significantly stronger bounds than dedicated particle physics experiments.
• These findings highlight the importance of considering astrophysical implications for fundamental physics models.