BNV

BNV typically refers to baryon number violation in particle physics. Baryon number is a quantum number assigned as +1 to baryons (such as protons and neutrons) and −1 to antibaryons. In the Standard Model, baryon number is conserved in perturbative interactions, so observable baryon-number violation is highly suppressed. However, non-perturbative effects related to electroweak processes can violate B+L (baryon plus lepton number) while preserving B−L, implying that baryon-number-violating phenomena could occur under certain conditions, such as at high energies or in the early universe.

In theories beyond the Standard Model, including Grand Unified Theories (GUTs) like SU(5) and SO(10), baryon-number-violating interactions arise more naturally. Such interactions can lead to rare processes including proton decay and neutron–antineutron oscillations. The detection of BNV would have profound implications for understanding the matter–antimatter asymmetry of the universe and the mechanisms of baryogenesis.

Experimental status remains one of non-observation. Proton-decay searches, especially in large detectors like Super-Kamiokande, have set stringent lower limits on the proton lifetime for various decay channels, often around 10^34 years. Searches for neutron–antineutron oscillations and other BNV processes have likewise produced strong constraints. Future experiments with larger detectors and higher intensities aim to improve sensitivity to potential BNV signals.

In summary, BNV denotes potential violations of baryon number that, if observed, would point to new physics beyond the Standard Model and offer key insights into the evolution of the universe.