based on : based on :
• PRDPRD8484, 051701 (2011) (arXiv:1103.1234), 051701 (2011) (arXiv:1103.1234)
w/ K. Kojima w/ K. Kojima (Kyushu) (Kyushu) & K. Takenaga & K. Takenaga (Kumamoto Health Science)(Kumamoto Health Science)
• PRDPRD8484, 115016 (2011) (arXiv:1106.3229), 115016 (2011) (arXiv:1106.3229)
Toshifumi Yamashita
MISC, Kyoto Sangyo U.
Aichi Medical U. 愛知医科大学 2012/3/14 @Kobe
2012/3/14 @Kobe
grand gauge-Higgs unification grand gauge-Higgs unification
& doublet-triplet splitting
& doublet-triplet splitting
GUT-breaking via
Hosotani mechanism
Outline
PRD84, 051701 (2011) w/ Kojima & Takenaga
• proposed this possibility:
grand gauge-Higgs unification
PRD84, 115016 (2011)
• SUSY version : testable Doublet-Triplet splitting We may get a hint of the GUT-breaking @LHC.
light adjoint
Plan
• Outline Outline
• quick review quick review
- DT splitting- DT splitting
- Hosotani mechanism- Hosotani mechanism
• grand GHU & DT splitting grand GHU & DT splitting
• low energy predictions low energy predictions
• summary summary
• unifications of forces and of matter
• charge quantization
• stabilization of the weak scale
• gauge coupling unification (GCU)
SUSY GUTs
Higgs?
Proton decay?
fascinating extension of SM
DT Splitting problem
SUSY SU(5) model
Fine-tuning of 1014!!
Solutions
DW mechanism SO(10) :• Sliding Singlet mechanism
• Missing partner mechanism
• Dimopoulos-Wilczek (DW) mechanism
• GIFT mechanism (Higgs as pNG)
• orbifold GUT, etc.
missing VEV
DT Splitting problem
Hosotani mechanism
• at first :
applied to GUT breaking (A5 : adjoint) in models w/o chiral fermions
Y. Kawamura (2000-)
• after orbifold breaking :
mainly applied to the EW breaking
• chiral fermion
• fundamental repr.
GUT breaking in models w/ chiral fermion?
K.Kojima & K.Takenaga & T.Y.
symmetry breaking by a continuous Wilson loop
VEV of zero-mode of A5
Y. Hosotani (1983)
gauge-Higgs unification
Hosotani mechanism
difficulty
• orbifold action projects out adjoint scalars
K.Kojima & K.Takenaga & T.Y.
• this difficulty is shared w/ heterotic string - well studied, classified w/ Kac-Moody level
- ``diagonal embedding” method
Why can’t we use this in our pheno. models?
grand gauge-Higgs unification
due to the opposite orbifold BCs.
e.g. Ito et.al. ( T.Y.) PRD(2011), JHEP(2011)flux cmpt?
Cf. Kobayashi’s talk
Plan
• Outline Outline
• quick review quick review
- DT splitting- DT splitting
- Hosotani mechanism- Hosotani mechanism
• grand GHU & DT splitting grand GHU & DT splitting
• low energy predictions low energy predictions
• summary summary
grand gauge-Higgs unification grand gauge-Higgs unification
diagonal embedding
K.R.Dienes & J.March-Russel (1996)K.Kojima & K.Takenaga & T.Y.
ex)
•
latticized picturesimilar to S1 model
chiral fermions
has a zero-mode.
This provides a way to “introduce”
chiral fermions in S
1models!!
grand gauge-Higgs unification grand gauge-Higgs unification
SU(5) example
SU(5) GSM on a local minimum where
(inversely) missing VEV
K.Kojima & K.Takenaga & T.Y.
T.Y. PRD (2011)
w/ appropriate bulk fermions
DT Splitting
T.Y. PRD (2011)
5 :
grand GHU & DT splitting grand GHU & DT splitting
basis transformation
(broken) gauge transformation w/
• BCs around are modified:
symmetry breaking by BCs,
as in the orbifold breaking
“DT splitting”
“anti-periodic” 5 scalar massless doublet
ex)
@ tree level
SUSY
T.Y. PRD (2011)
grand GHU & DT splitting grand GHU & DT splitting
basis transformation
(broken) gauge transformation w/
• BCs around are modified:
ex)
“DT splitting
“anti-periodic” 5 chiral massless doublet SUSY
5 :
symmetry breaking by BCs,
as in the orbifold breaking
grand GHU & DT splitting grand GHU & DT splitting
matter content
bulk fields
• similar to S1 model : vector-like
• couple to PW : SU(5) incomplete multiplets
boundary fields
• essentially 4D fields : chiral
• not couple to PW : SU(5) full multiplets Hu & Hd
chiral matter
Plan
• Outline Outline
• quick review quick review
- DT splitting- DT splitting
- Hosotani mechanism- Hosotani mechanism
• grand GHU & DT splitting grand GHU & DT splitting
• low energy predictions low energy predictions
• summary summary
low energy predictions low energy predictions
light adjoint chiral multiplets
• A5 is massless @tree level,
and acquires a mass of O(mSB) via loop.
Its superpartners can have masses of O(mSB).
We may observe .
gauge coupling unification
• The adjoint matters : recovered w/
to remain perturbative
T.Y. PRD (2011)
low energy predictions low energy predictions
recovery of GCU
ex) additional matters for :
5 10 (in the bulk)
T.Y. PRD (2011)
- MSSM
- MSSM + adj
- MSSM + adj + add
phenomenology of adjoints
low energy predictions low energy predictions
• SU(3) is no longer asymptotically free, and remains strong @high energy squarks & octet become rather heavy.
• colorless fields may be produced @LHC.
• these may contribute to the higgs mass.
(SUSY) triplet/(doublet)/singlet Higgs model.
e.g.
NMSSM-like and/or through loop
M.Kakizaki, S.Kanemura, H.Tanigucji & T.Y.
: now working
Prelim y inar
heavier higgs
• a (local) vacuum : SU(5) GSM
summary
Hosotani-breaking of GUT symmetry
PRD84, 051701 (2011) w/ K.Kojima & K.Takenaga
• proposed this possibility, grand gauge-Higgs unification.
PRD84, 115016 (2011)
• SUSY version : DT splitting realized naturally
• general prediction : light adjoint chiral w/
may be tested @LHC
e.g. direct production of a weak triplet, heavy squarks & higgs