Motivations and Intro Model Building Some phenomenology Summary Composite GUTs: model building and expectations at the LHC M. Frigerio J. Serra A. Varagnolo based on 1103.2997 [hep-ph], JHEP 1106:029,2011 Supersymmetry 2011, Fermilab Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building Some phenomenology Summary Composite GUTs: model building and facing the LHC M. Frigerio J. Serra A. Varagnolo based on 1103.2997 [hep-ph], JHEP 1106:029,2011 Supersymmetry 2011, Fermilab Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building Some phenomenology Summary Outline Motivations and Intro 1 SUSY & the ALTERNATIVES Some tools Model Building 2 The idea, and real life Our pNGBs, our Exotics and the EWPTs Some phenomenology 3 Some doubts Some hope Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Outline Motivations and Intro 1 SUSY & the ALTERNATIVES Some tools Model Building 2 The idea, and real life Our pNGBs, our Exotics and the EWPTs Some phenomenology 3 Some doubts Some hope Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Motivations for CompoGUTs Unification and its many appealing virtues charge quantization gauge quantum numbers of fermions chiral anomalies cancellation relative low energy values of SM gauge couplings and more (DM stability, masses of ν s,...) solution to the Hierarchy Problem (orthogonal to SUSY) predict properties of lightest states coming from the new Strong Sector: partners of Higgs and top accept the LHC challenge Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary SUSY Why we love SUSY: Solution to the Hierarchy Problem Improves Unification (with full perturbativity up to M GUT ) Rich Pheno: new states predicted (Dark Matter?) Of course, we do have some complaints/doubts: need for extra symmetry to avoid, e.g., p-decay (R-parity) parameter space for simplest models of SUSY shrinking nature has shown us other ways (QCD, SC) All in all, not unwise to consider alternatives Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary ALTERNATIVES The big thing : Solve the HP. Many candidates: Technicolour, Higgsless, Extra Dimensions, . . . Composite Higgs. Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary ALTERNATIVES The big thing : Solve the HP. Many candidates: Technicolour, Higgsless, Extra Dimensions, . . . Composite Higgs. Focus on CH scenario: Solution to HP → move to the little HP (Fine Tuning!) ?? Unification ?? not perturbative! ?? New states ?? Huge model dependence + some of them we cannot control (heavy resonances) ← the price of having a Low E effective description Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary ALTERNATIVES The big thing : Solve the HP. Many candidates: Technicolour, Higgsless, Extra Dimensions, . . . Composite Higgs. Focus on CH scenario: Solution to HP → move to the little HP (Fine Tuning!) ?? Unification ?? not perturbative! ?? New states ?? Huge model dependence + some of them we cannot control (heavy resonances) ← the price of having a Low E effective description One step at a time. Why can’t we tell if our model unifies? Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Do you know your beta functions? Or: how to check if Unification occurs MSSM: Good Unif (@ 1-loop) SM: Unif fails SM MSSM 1 1 Α � Μ � Α � Μ � 60 60 50 50 40 40 30 30 20 20 10 17 Μ � GeV � 10 17 Μ � GeV � 10 5 10 8 10 11 10 14 10 5 10 8 10 11 10 14 Higher Orders: NO help Higher Orders: a bit worse Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Do you know your beta functions? Or: how to check if Unification occurs MSSM: Good Unif (@ 1-loop) SM: Unif fails SM MSSM 1 1 Α � Μ � Α � Μ � 60 60 50 50 40 40 30 30 20 20 10 17 Μ � GeV � 10 17 Μ � GeV � 10 5 10 8 10 11 10 14 10 5 10 8 10 11 10 14 Higher Orders: NO help Higher Orders: a bit worse What about Composite Higgs (+ top)? Can we calculate? Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Do you know your beta functions? Or: how to check if Unification occurs MSSM: Good Unif (@ 1-loop) MSSM 1 Α � Μ � Compositeness vs Unif 60 50 40 i i 30 20 Leading order UNKNOWN 10 17 Μ � GeV � 10 5 10 8 10 11 10 14 Higher Orders: a bit worse What about Composite Higgs (+ top)? Can we calculate? Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Do you know your beta functions? Or: how to check if Unification occurs Compositeness vs Unif Our ignorance is partial � 1 + b comp = b elem d � i i i i , d ln µ α i 2 π 2 π elementary contribution is KNOWN Leading order UNKNOWN Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Do you know your beta functions? Or: how to check if Unification occurs Compositeness vs Unif Our ignorance is partial � 1 + b comp = b elem � d i i i i , d ln µ α i 2 π 2 π elementary contribution is KNOWN Leading order UNKNOWN Notice: the differential running determines unification 1 . 1 provided no Landau pole is hit Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Do you know your beta functions? Or: how to check if Unification occurs Compositeness vs Unif Our ignorance is partial � 1 + b comp = b elem � d i i i i , d ln µ α i 2 π 2 π elementary contribution is KNOWN Leading order UNKNOWN Notice: the differential running determines unification 1 . A good measure: R ≡ ( b 1 − b 2 ) / ( b 2 − b 3 ) . Numerically, we have: R exp = 1 . 395 ± 0 . 015 vs R th SM ≃ 1 . 9 vs R th MSSM = 1 . 4 vs ?? 1 provided no Landau pole is hit Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building SUSY & the ALTERNATIVES Some phenomenology Some tools Summary Composite Higgs New Strong Dynamics triggers G / K global symm breaking, NGBs π s.t. π ⊃ H , with σ -model scale f @ Low E: L = L G SM composite + L G SM elementary + L G → K mixing The mixing term will generate (CW) a V eff ( π ) � = 0. Fine Tun- ing measure: ξ = v 2 / f 2 . Resonances @ scale m ρ ∼ few TeV , inter-compo coupling: g ρ = m ρ / f , g elem ≤ g ρ ≤ 4 π Composite Top A closer look: L G SM mixing = λ ψ L ψ L O ψ L + λ ψ R ψ R O ψ R + g i A i µ J µ Yukawa: y ψ ≃ λ ψ L λ ψ R / g ρ → top mostly/totally composite. Must choose t R , otherwise big troubles a with Zb ¯ b v 2 / f 2 → Better impose Custodial Symmetry ˆ Also: T ≃ ( SU ( 2 ) L × SU ( 2 ) R ) on the whole Strong Sector a Can cure this by extending CS with LR parity. Check r-h coupling! Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building The idea, and real life Some phenomenology Our pNGBs, our Exotics and the EWPTs Summary Outline Motivations and Intro 1 SUSY & the ALTERNATIVES Some tools Model Building 2 The idea, and real life Our pNGBs, our Exotics and the EWPTs Some phenomenology 3 Some doubts Some hope Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building The idea, and real life Some phenomenology Our pNGBs, our Exotics and the EWPTs Summary A way out G / K → Composite stuff (i.e. Higgs, top, heavy resonances) Agashe, Contino, Sundrum (2005) realized that if G SM ⊂ G simple ⇒ contribution of strong sector to b i s above compositeness scale becomes universal! ( b compo → b compo ) i Then b i − b j = b elem − b elem and we can compute! (modulo i j small corrections from Low E region, if K is not simple) Equivalently: we subtract the contributions of composite modes to the differential running, i.e. R ( SM ) → R ( SM \ { Composite stuff } ) We are thus in a position to investigate Composite Unification. Alvise Varagnolo Compo GUTs
Motivations and Intro Model Building The idea, and real life Some phenomenology Our pNGBs, our Exotics and the EWPTs Summary A way out G / K → Composite stuff (i.e. Higgs, top, heavy resonances) Agashe, Contino, Sundrum (2005) realized that if G SM ⊂ G simple ⇒ contribution of strong sector to b i s above compositeness scale becomes universal! ( b compo → b compo ) i Then b i − b j = b elem − b elem and we can compute! (modulo i j small corrections from Low E region, if K is not simple) Equivalently: we subtract the contributions of composite modes to the differential running, i.e. R ( SM ) → R ( SM \ { Composite stuff } ) We are thus in a position to investigate Composite Unification. But careful: b compo < 10, or you hit a Landau pole before M GUT ! Alvise Varagnolo Compo GUTs
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