to measurement errors. The result was consistent with the speed of light; see Faster-than-light neutrino anomaly. In 2010, MINOS reported differences between the disappearance (and thus the masses) of neutrinos and antineutrinos at the 2.3 sigma level. This would violate CPT symmetry and Lorentz symmetry. However, in 2011 MINOS updated their antineutrino results; after evaluating additional data, they reported that the difference is not as great as initially thought. In 2012, they published a paper in which they reported that the difference is now removed. In 2007, the MAGIC Collaboration published a paper, in which they claimed a possible energy dependence of the speed of photons from the galaxy Markarian 501. They admitted, that also a possible energy-dependent emission effect could have cause this result as well. However, the MAGIC result was superseded by the substantially more precise measurements of the Fermi-LAT group, which couldn't find any effect even beyond the Planck energy. For details, see section Dispersion. In 1997, Nodland & Ralston claimed to have found a rotation of the polarization plane of light coming from distant radio galaxies. This would indicate an anisotropy of space. This attracted some interest in the media. However, some criticisms immediately appeared, which disputed the interpretation of the data, and who alluded to errors in the publication. More recent studies have not found any evidence for this effect (see section on Birefringence). See also Tests of special relativity Phenomenological quantum gravity References External links Kostelecký: Background information on Lorentz and CPT violation Roberts, Schleif (2006); Relativity FAQ: What is the experimental basis of special relativity? Physics experiments Tests of special relativity