## CPT Violation Observed at Fermilab?

Tommaso Dorigo posted on his blog about a new paper1 from the CDF collaboration at Fermilab. The CDF team report an analysis of Tevatron data which indicates a mass difference between the top quark and the anti-top quark. If this data is born out by further observations and analysis, this would indicate a violation of CPT symmetry, which in turn implies a violation of Lorentz Invariance2. This would require re-thinking certain assumptions about the Standard Model, especially with respect to proofs of the spin-statistics theorem, as well as to special and general relativity3. It should be pointed out that this is not the first experimental result to imply such violations4.

1. CDF Collaboration, “Measurement of the mass difference between $t$ and $\bar{t}$ quarks”, submitted to Phys. Rev. Lett. arXiv:1103.2782v1 [hep-ex]
2. Greenberg, O.W. (2002). “CPT Violation Implies Violation of Lorentz Invariance”. Physical Review Letters 89: 231602. doi:10.1103/PhysRevLett.89.231602arXiv:hep-ph/0201258.
3. Background information on Lorentz and CPT Violation
4. Devasia, S. (2010). “Lorentz violation in high-energy ions”. The European Physical Journal C – Particles and Fields 69 (3-4): 343–346. doi:10.1140/epjc/s10052-010-1437-9