Baryon and lepton numbers: where do we stand? by Ch. Smith (LPSC)

Thursday 24 Jan 2013, 11:00 → 12:00 Europe/Paris

Amphi (LPSC)

One of the most puzzling questions in particle physics concerns the status of the baryon (B) and lepton (L) quantum numbers. On the theoretical side, they are not expected to be conserved in Nature. Most New Physics scenarios naturally lead to their non-conservation and some amount of violation is actually needed to explain the baryon asymmetry of the Universe. On the experimental side, however, low-energy constraints such as those on proton decay are so stringent that it is generally believed no B and L violation will ever be seen in laboratories. In the present talk, we will first review the status of B and L: historical developments, current experimental results, and theoretical expectations. Then, we will explain how low-energy constraints on their non-conservation can be circumvented, and show that striking signals are within reach of the LHC. So, with dedicated studies and more data, the LHC offers us a fantastic opportunity to finally unravel the true status of the B and L quantum numbers in Nature.