1. Searches for New Physics Motivations Examples Searches so far Setting scene for LHC 1/12

2. Status of the Standard Model Perfect agreement with all confirmed accelerator data Consistency with precision electroweak data (LEP et al) only if there is a Higgs boson Agreement seems to require a relatively light Higgs boson weighing < ~ 200 GeV Raises many unanswered questions: mass? flavour? unification?

3. New Electroweak Physics? Limit new contributions to vacuum polarization due, e.g., to new fermions Check energy-dependence of radiative corrections

4. Searches for New Gauge Bosons Limits on W’, Z’ from Tevatron

5. Accelerator Evidence for New Physics? The anomalous (?) anomalous magnetic moment of the muon Disagrees with the SM @ 3.3  level if use e + e - annihilation data But no discrepancy if use  decay data Jury still out

6. Open Questions beyond the Standard Model What is the origin of particle masses? due to a Higgs boson? + other physics? solution at energy < 1 TeV (1000 GeV) Why so many types of matter particles? matter-antimatter difference? Unification of the fundamental forces? at very high energy ~ 10 16 GeV? probe directly via baryon decay, neutrino physics, indirectly via masses, couplings Quantum theory of gravity? (super)string theory: extra space-time dimensions? LHC

7. At what Energy is the New Physics? A lot accessible directly to the LHC Some accessible only indirectly: Astrophysics and cosmology? Dark matter Origin of mass

8. Some particles have mass, some do not +10-1 W + Z 0 W - Mass 80.419 91.188 80.419 0 photon Mass 0 Wheredothemasses come from? Newton: Weight proportional to Mass Einstein: Energy related to Mass Neither explained origin of Mass Are masses due to Higgs boson? (yet another particle)

9. Higgs Searches What to look for in the SM: No luck at LEP: Nor at the Tevatron … … so far!

10. Progress in the Higgs Search @ Tevatron Many measurements of other SM processes Factor > 10 before SM Higgs sensitivity

11. Theorists getting Cold Feet Composite Higgs model? fermion masses? precision electroweak data? Interpretation of EW data? consistency of measurements? Discard some? Higgs + higher-dimensional operators? corridors to higher Higgs masses? Little Higgs models? extra `Top’, gauge bosons, `Higgses’ Higgsless models? strong WW scattering, extra D? Kraml et al: hep-ph/0608079

12. Elementary Higgs or Composite? Higgs field: ≠ 0 Quantum loop problems Fermion-antifermion condensate Just like QCD, BCS superconductivity Top-antitop condensate? needed m t > 200 GeV New technicolour force? consistency with precision electroweak data? Cut-off Λ ~ 1 TeV with Supersymmetry? Cutoff Λ = 10 TeV

13. Searches for Technicolour

14. What is Supersymmetry (Susy)? The last undiscovered symmetry? Could unify matter and force particles Links fermions and bosons Relates particles of different spins 0 - ½ - 1 - 3/2 - 2 Higgs - Electron - Photon - Gravitino - Graviton Helps fix masses, unify fundamental forces

15. Other Reasons to like Susy It enables the gauge couplings to unify It predicts m H < 150 GeV JE, Nanopoulos, Olive + Santoso: hep-ph/0509331 As suggested by EW data Erler: 2006

16. Astronomers say that most of the matter in the Universe is invisible Dark Matter Lightest Supersymmetric particles ? We shall look for them with the LHC

17. Constraints on Supersymmetry Absence of sparticles at LEP, Tevatron selectron, chargino > 100 GeV squarks, gluino > 250 GeV Indirect constraints Higgs > 114 GeV, b → s γ Density of dark matter lightest sparticle χ: WMAP: 0.094 < Ω χ h 2 < 0.124 3.3 σ effect in g μ – 2?

18. Classic Supersymmetric Signature Missing transverse energy carried away by dark matter particles

19. Limits on Sparticles

20. Current Constraints on CMSSM WMAP constraint on relic density Excluded because stau LSP Excluded by b  s gamma Excluded (?) by latest g - 2 Focus-point region at large m 0 Assuming the lightest sparticle is a neutralino JE + Olive + Santoso + Spanos

21. Sparticles may not be very light Full Model samples Detectable @ LHC Provide Dark Matter Detectable Directly Lightest visible sparticle → ← Second lightest visible sparticle JE + Olive + Santoso + Spanos

22. Strategies for Detecting Supersymmetric Dark Matter Annihilation in galactic halo χ – χ  antiprotons, positrons, …? Annihilation in galactic centre χ – χ  γ + …? Annihilation in core of Sun or Earth χ – χ  ν + …  μ + … Scattering on nucleus in laboratory χ + A  χ + A

23. Search for Supersymmetric Dark Matter Limits on scattering of dark matter vs Predictions in some susy models

24. Open Questions beyond the Standard Model What is the origin of particle masses? due to a Higgs boson? + other physics? solution at energy < 1 TeV (1000 GeV) Why so many types of matter particles? matter-antimatter difference? Unification of the fundamental forces? at very high energy ~ 10 16 GeV? probe directly via baryon decay, neutrino physics, indirectly via masses, couplings Quantum theory of gravity? (super)string theory: extra space-time dimensions?

25. New Physics Constraints from B Mesons Good consistency with CKM predictions Start to constrain BSM, e.g., supersymmetry

26. Searches for ‘Axions’ Solve strong CP problem Constraints from astrophysics Laboratory searches begin to bite Variants also considered

27. Search for CPT Violation Probes with neutral kaons Look for mass, lifetime differences Quantum gravity might yield decoherence? would violate CPT

28. Open Questions beyond the Standard Model What is the origin of particle masses? due to a Higgs boson? + other physics? solution at energy < 1 TeV (1000 GeV) Why so many types of matter particles? matter-antimatter difference? Unification of the fundamental forces? at very high energy ~ 10 16 GeV? probe directly via baryon decay, neutrino physics, indirectly via masses, couplings Quantum theory of gravity? (super)string theory: extra space-time dimensions?

29. Searches for Baryon Decay Compilation of limits on different decay modes

30. New Gravitational Physics? Indirect evidence for gravitational waves Limits on deviations from Einstein/Newton

31. String Theory Candidate for reconciling gravity with quantum mechanics Point-like particles → extended objects Simplest possibility: lengths of string Quantum consistency fixes # dimensions: Bosonic string: 26, superstring: 10 Must compactify extra dimensions, scale ~ 1/m P ? Or larger? Any way to test it?

32. How large could extra Dimensions be? 1/TeV? could break supersymmetry, electroweak micron? can rewrite hierarchy problem Infinite? warped compactifications Look for black holes, Kaluza-Klein excitations @ colliders?

33. And if gravity becomes strong at the TeV scale … Black Hole Production at LHC? Multiple jets, leptons from Hawking radiation

34. … but sometimes not Sometimes New Particles appear as they were expected … SEARCH FOR GLUONS IN e+ e- ANNIHILATION. John R. EllisJohn R. Ellis, Mary K. Gaillard, Graham G. Ross.Mary K. GaillardGraham G. Ross CERN-TH-2161, Apr 1976, Nucl.Phys.B111:253,1976

35. Haiku by Matsuo Basho In a way, it was quite fun not to see Mount Fuji in foggy rain –Interesting for theorists –But the politicians would rather we found something