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Published byLoreen Shelton Modified over 9 years ago
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Unification Hints The Standard Model: Partial Unification
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Matter Sector “chiral” Family Symmetry? Neutral Up Down Family Symmetry?
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Standard Model parameters Cabibbo, Kobayashi, Maskawa
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} } ? ? ? e e Grand Unification
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-u c ucuc ud ucuc ud u d ecec } } dcdc dcdc dc e e Grand Unification LH states SU(2) doublets {
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-u c ucuc ud ucuc ud u d ecec } } dcdc dcdc dc e e Grand Unification -t c tctc tb tctc tb tb cc bcbc bcbc bcbc -u c ucuc ud ucuc ud u d ecec ucuc ud ucuc ud u d ecec dcdc dcdc dcdc e e -c cc cs c cs cs cc scsc scsc scsc Generations (?)
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-u c ucuc ud ucuc ud u d ecec dcdc dcdc dc e e Grand Unification } : New lepto-quark gauge interactions } u u dcdc e+e+
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Neutrino Mass <H><H> <H><H> Grand Unification +5
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-u c ucuc ud ucuc ud u d ecec } } dcdc dcdc dc e e Gauge Couplings +
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Precision Measuremets 30 60 50 40 20 10 0 Log 10 [Energy Scale (GeV)] 357911131517 1 -1 2 -1 3 -1 Either: No Grand Unification or: more particles... Either: No Grand Unification or: more particles...
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Supersymmetry threshold Log 10 [Energy Scale (GeV)] 357911131517 1 -1 2 -1 3 -1 TeV scale supersymmetry
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String theory World sheet } String tension OpenClosed
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String Structure : 1 st string revolution Ghost free condition : D=10 Fermionic (+SUSY) E8 SO(32) Type I Type IIA Type IIB String excitations : J m2 Compactification D=10 D=4 +(D=6) compactified – radius R Kaluza Klein & winding modes Gauge structure : restricted by anomaly cancellation Green Schwarz +chiral structure for q, l ; multiplet structure determined by topology of manifold : Calabi Yau - 3 generation examples known Supersymmetry (c.f. D=26 Bosonic) †
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String Structure : 2nd string revolution E8 SO(32) Type I Type IIA Type IIB D=11 supergravity M String dualities D-branes Submanifold on which open strings start or end
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String phenomenology How can we distinguish them?
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Supersymmetry threshold Log 10 [Energy Scale (GeV)] 357911131517 1 -1 2 -1 3 -1 TeV scale supersymmetry
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I GGR, D.Ghilencea SUSY gauge coupling unification
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I Unification Hints × 3,2,1 E 10 -60 TeV M Pl anck Gravitational coupling 1/r 2+n 1/r p Gauge coupling ? Unification at a TeV?
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Warped Unification RS1 TeV Brane All scales up to Planck scale present - logarithmic running of gauge couplings! Randall, Schwarz Sundrum, Delgardo,... Choi, Kim, Kim × D=5
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I Updated fit : E 10 -60 MPMP 3,2,1 G N (Q) Q 2 Unification with gravity? SUSY coupling unification
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} } Gauge unification - Heterotic String
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String Threshold Effects (WCHS) N=2 KK modesWinding modes Dixon, Kaplunovsky, Louis
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Threshold sensitivity To preserve insensitivity to heavy thresholds (no power law sensitivity) need Ghilencea,GGR
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Weakly coupled heterotic strings with Wilson line breaking Discrete group Physical states : e.g.
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Reduction in X,Y boson contribution - equivalent to reduction in unification scale. } (14)
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N=3, n=1N=7, n=1N=7, n=2N=7, n=3 3.64 (4.12)3.68 (4.43)3.71 (3.78))4.81 (6.75) -0.25 (-0.27)-0.25 (-0.28)-0.25 (-0.25)-0.30 (-0.36) 2.81 (3.10)2.84 (3.29)2.86 (2.90)3.50 (4.61) 0.49 (0.54)0.50 (0.57)0.50 (0.51)0.60 (0.73) Quantitative effect of Wilson lines : No Higgs KK modes Higgs KK modes 2D1D or 2D (matter KK modes degenerate) GGR
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String profile from gauge unification WCHS + Wilson line
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