Astronomy and Astrophysics – Astrophysics – High Energy Astrophysical Phenomena
Scientific paper
2009-03-02
J.Phys.Conf.Ser.174:012016,2009
Astronomy and Astrophysics
Astrophysics
High Energy Astrophysical Phenomena
34 pages latex, 12 eps figures incorporated, uses special macros. Based on invited plenary talk at DICE 2008 Conference (Casti
Scientific paper
10.1088/1742-6596/174/1/012016
There have been observations, first from the MAGIC Telescope (July 2005) and quite recently (September 2008) from the FERMI Satellite Telescope, on non-simultaneous arrival of high-energy photons from distant celestial sources. In each case, the highest energy photons were delayed, as compared to their lower-energy counterparts. Although the astrophysics at the source of these energetic photons is still not understood, and such non simultaneous arrival might be due to non simultaneous emission as a result of conventional physics effects, nevertheless, rather surprisingly, the observed time delays can also fit excellently some scenarios in quantum gravity, predicting Lorentz violating space-time "foam" backgrounds with a non-trivial subluminal vacuum refractive index suppressed linearly by a quantum gravity scale of the order of the reduced Planck mass. In this pedagogical talk, I discuss the MAGIC and FERMI findings in this context and I argue on a theoretical model of space-time foam in string/brane theory that can accommodate the findings of those experiments in agreement with all other stringent tests of Lorentz invariance. However, I stress the current ambiguities/uncertainties on the source mechanisms, which need to be resolved first before definite conclusions are reached regarding quantum gravity foam scenarios.
No associations
LandOfFree
High-Energy gamma-ray Astronomy and String Theory does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with High-Energy gamma-ray Astronomy and String Theory, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High-Energy gamma-ray Astronomy and String Theory will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-78272