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lpetrich
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I first thought of posting on cataloguing various Grand Unified Theory proposals, but that would be an enormous task, so I decided on something simpler: cataloguing proposed GUT gauge-symmetry groups.
The unbroken Standard-Model symmetry is SU(3)C * SU(2)L * U(1)Y
QCD:
SU(3)C -- color
Electroweak:
SU(2)L -- weak isospin
U(1)Y -- weak hypercharge
I'll consider gauge particles, Higgs particles, and elementary fermions (EF's), complete with right-handed neutrinos (RHN).
The GUT's:
SU(5) -- Georgi-Glashow
Gauge: 1, Higgs: 2, EF's: 3 (one of them is RHN)
SU(4)*SU(2)*SU(2) or SO(6)*SO(4) -- Pati-Salam
Gauge: 3, Higgs: 1, EF's: 2 (includes RHN)
SO(10)
Gauge: 1, Higgs: 1, EF's: 1 (includes RHN)
SO(10) can break into Georgi-Glashow or Pati-Salam
SU(3)*SU(3)*SU(3) -- trinification
Gauge: 3, EF's: 3 (includes RHN; one of them also can contain the Higgs)
E(6)
Gauge: 1, EF's: 1 (can also contain the Higgs)
E(6) can break into SO(10) or trinification
E(8)
Everything in the 248 fundamental / adjoint multiplet, including all three generations of EF's.
E(8) can break into E(6)*SU(3), SO(10)*SU(4), or SU(5)*SU(5)
SU(6)
Gauge: 1, EF's: 3 (includes RHN; can also contain the Higgs)
SU(6) can break into SU(5)
ETA: E(6) can break into SU(6)
Any others that anyone has proposed?
The unbroken Standard-Model symmetry is SU(3)C * SU(2)L * U(1)Y
QCD:
SU(3)C -- color
Electroweak:
SU(2)L -- weak isospin
U(1)Y -- weak hypercharge
I'll consider gauge particles, Higgs particles, and elementary fermions (EF's), complete with right-handed neutrinos (RHN).
The GUT's:
SU(5) -- Georgi-Glashow
Gauge: 1, Higgs: 2, EF's: 3 (one of them is RHN)
SU(4)*SU(2)*SU(2) or SO(6)*SO(4) -- Pati-Salam
Gauge: 3, Higgs: 1, EF's: 2 (includes RHN)
SO(10)
Gauge: 1, Higgs: 1, EF's: 1 (includes RHN)
SO(10) can break into Georgi-Glashow or Pati-Salam
SU(3)*SU(3)*SU(3) -- trinification
Gauge: 3, EF's: 3 (includes RHN; one of them also can contain the Higgs)
E(6)
Gauge: 1, EF's: 1 (can also contain the Higgs)
E(6) can break into SO(10) or trinification
E(8)
Everything in the 248 fundamental / adjoint multiplet, including all three generations of EF's.
E(8) can break into E(6)*SU(3), SO(10)*SU(4), or SU(5)*SU(5)
SU(6)
Gauge: 1, EF's: 3 (includes RHN; can also contain the Higgs)
SU(6) can break into SU(5)
ETA: E(6) can break into SU(6)
Any others that anyone has proposed?
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