Georgi–Jarlskog mass relation explained

In grand unified theories of the SU(5) or SO(10) type, there is a mass relation predicted between the electron and the down quark, the muon and the strange quark and the tau lepton and the bottom quark called the Georgi–Jarlskog mass relations. The relations were formulated by Howard Georgi and Cecilia Jarlskog.^[1]

At GUT scale, these are sometimes quoted as:

m _{e} ≈ (1)/(3) m _{d} m _{\mu} ≈ 3 m _{s} m _{\tau} ≈ m _{b}

In the same paper it is written that:

m _{d} ≈ (1)/(3) m _{d} m _{s} ≈ (1)/(3) m _{s} m _{b} ≈ (1)/(3) m _{b}

Meaning that:

m _{d} ≈ 9 m _{e} error = 5 \% m _{s} ≈ m _{\mu} error = 21 \% m _{b} ≈ 3 m _{\tau} error = 26 \%

Current values for Lepton and Quark masses

Symbol	Description	Renormalization scheme (point)	Value
me	Electron mass		0.511 MeV
mu	Up quark mass	μ = 2 GeV	1.9 MeV
md	Down quark mass	μ = 2 GeV	4.4 MeV
ms	Strange quark mass	μ = 2 GeV	87 MeV
mμ	Muon mass		105.7 MeV
mc	Charm quark mass	μ = mc	1.32 GeV
mτ	Tau mass		1.78 GeV
mb	Bottom quark mass	μ = mb	4.24 GeV
mt	Top quark mass	On-shell scheme	172.7 GeV

Notes and References

1. Georgi . H. . Jarlskog . C. . 10.1016/0370-2693(79)90842-6 . A new lepton-quark mass relation in a unified theory . 1979 . . 86 . 3–4 . 297–300 . 1979PhLB...86..297G .