1.4k citations
- Texas A&M UniversityUS282 papers
- Academy of AthensGR204 papers
- European Organization for Nuclear ResearchCH141 papers
- Institute of Theoretical PhysicsCN77 papers
- Chinese Academy of SciencesCN75 papers
- King's College LondonGB60 papers
- Mitchell InstituteUS50 papers
- University of MinnesotaUS41 papers
- Sam Houston State UniversityUS27 papers
- Kavli Institute for Theoretical SciencesCN26 papers
- University of OxfordGB25 papers
- Rice UniversityUS21 papers
Showing astro-ph.HEShow all
2 papers · 1 filter
astro-ph.HE2010★ 16 cited
Comments on Ultra-High-Energy Photons and D-Foam models
John Ellis, Nick E. Mavromatos, Dimitri V. Nanopoulos
We revisit the constraints that the non-observation of ultra-high-energy photons due to the GZK cutoff can impose on models of Lorentz violation in photon propagation, following re…
astro-ph.HE2009★ 61 cited
Probing a Possible Vacuum Refractive Index with Gamma-Ray Telescopes
John Ellis, N. E. Mavromatos, D. V. Nanopoulos
We have used a stringy model of quantum space-time foam to suggest that the vacuum may exhibit a non-trivial refractive index depending linearly on gamma-ray energy: eta -1 ~ E_gam…