# B − L

> quantum number (difference between the baryon number and the lepton number), conserved in some grand unified theories even when baryon and lepton numbers are not separately conserved

**Wikidata**: [Q2567685](https://www.wikidata.org/wiki/Q2567685)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/B_−_L)  
**Source**: https://4ort.xyz/entity/b-l-q2567685


## References

1. Freebase Data Dumps. 2013