# Astrophysical Searches for Quantum Gravity Signals

### APA

Granot, J. (2012). Astrophysical Searches for Quantum Gravity Signals . Perimeter Institute. https://pirsa.org/12100058

### MLA

Granot, Jonathan. Astrophysical Searches for Quantum Gravity Signals . Perimeter Institute, Oct. 24, 2012, https://pirsa.org/12100058

### BibTex

@misc{ pirsa_PIRSA:12100058, doi = {10.48660/12100058}, url = {https://pirsa.org/12100058}, author = {Granot, Jonathan}, keywords = {Quantum Gravity}, language = {en}, title = {Astrophysical Searches for Quantum Gravity Signals }, publisher = {Perimeter Institute}, year = {2012}, month = {oct}, note = {PIRSA:12100058 see, \url{https://pirsa.org}} }

University of Hertfordshire

**Collection**

Talk Type

**Subject**

Abstract

Some recent searches for quantum gravity signatures using
observations of distant astrophysical sources will be discussed, focusing on
the search for Lorentz invariance violation (LIV) in the form of a dependence
of the photon propagation speed on its energy. Fermi gamma-ray space telescope
observations of ~8 keV to ~30 GeV photons from a short (< 1 s) gamma-ray
burst (GRB 090510) at a cosmological distance (z = 0.903), enabled for the
first time to put a direct time of flight limit on a possible linear variation of
the speed of light with photon energy that is beyond the Planck scale.
Parameterizing
|v/c-1| = E/E_{QG} our most conservative limits are
E_{QG}/E_{Planck}
> 1.2, while less conservative limits are up to 1-2
orders of
magnitude stricter. Other types of astrophysical searches
for LIV will be briefly outlined, along with some prospects for the future.