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An Excursion Into the Attouniverse and Beyond

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An Excursion Into the Attouniverse and Beyond An Excursion into the Attouniverse and Beyond Andrzej J. Buras (Technical University Munich, TUM-IAS) Schrödinger Gastprofessur Vienna, 19.10.2010 Vienna1010 1 Overture Vienna1010 2 A very important year for the humanity ! Vienna1010 3 1676 : The Discovery of the Microuniverse (Animalcula) (The Empire of Bacteria) 10-6m Antoni van Leeuwenhoek *24.10.1632 <27.08.1723 (Magnification ~500 Microscopes by ~300) Vienna1010 4 Microbe Hunters Antoni van Leeuwenhoek Lazzaro Spallanzani *24.10.1632 <27.08.1723 *12.01.1729 <12.02.1799 L. Pasteur Robert Koch Vienna1010 5 *27.12.1822 <28.09.1895 *11.12.1843 <27.05.1910 An Excursion towards the Very Short Distance Scales: 1676 - 2020 Microuniverse 10-6m Bacteriology Microbiology Nanouniverse 10-9m Nanoscience Nuclear Physics Femtouniverse 10-15m Low Energy Elementary Particle Physics Attouniverse 10-18m High Energy Particle Physics (present) High Energy Proton-Proton 5·10-20m Collisions at the LHC Frontiers of Elementary High Precision Measurements Particle Physics in 2010´s of Rare Processes (Europe, 10-22m Japan, USA) Vienna1010 6 The Technology for the Microuniverse Robert Koch *11.12.1843 <27.05.1910 Vienna1010 7 Technology to go beyond the Attouniverse Methodology Vienna1010 8 LargeLarge HadronHadron ColliderCollider atat CERNCERN Glion Colloquium / June 2009 9 Vienna1010 9 How small is really 10-18m ? Vienna1010 10 How small is really 10-18m ? 109m Earth 3 light seconds Moon 0.4 · 109m Vienna1010 11 How small is really 10-18m ? 109m Earth 3 light seconds Moon 0.4 · 109m 1018m 105 light years Vienna1010 12 How small is really 10-18m ? 109m Earth 3 light seconds Moon 0.4 · 109m 1018m 105 light years Earth Beta Ceti (Deneb Kaitos 92 light years in the constellation Cetus) Vienna1010 13 Vienna1010 14 Vienna1010 15 Kepler Searching for new Planetary Systems and New Lifes March 2009 NASA Vienna1010 16 Most important Message from this Talk Antoni van Leeuwenhook discovered in 1676 Das Reich des mikroskopisch Kleinen (Animalcula) Elementary Particle Physicists expect to discover New Animalcula in the coming years with the help of LHC and High Precision Experiments Vienna1010 17 Next 57 min st 1 : Introducing the Attouniverse (33 min) Movement nd 2 : Expectations for New Animalcula Movement (10 min) 3rd : First Messages from New Animalcula Movement (7 min) th 4 : Final Messages (TUM, IAS, EC) (7 min) Movement Vienna1010 18 1st Movement Introducing the Attouniverse Vienna1010 19 How to explore the Attouniverse ? Heisenberg’s h ΔΔx ⋅≥ p h Uncertainty : 2 h = Distance Momentum 2π Principle Interval Interval h=Planck’s constant Use h == c1 : Speed of light In order to explore: Femtouniverse : E ≈ 200 MeV ≈ mπ Emc=+2224 E = p2 c mc Attouniverse : E ≈ 200 GeV ≈ mtop 10-19m E ≈ 2000 GeV = 2 TeV E=+ m E = p2 m2 MeV = 106eV GeV = 109eV ()ppm=≈>>0 22 for p2 (proton mass) Vienna1010 20 What do we know about the Attouniverse ? Vienna1010 21 Periodic Table of Elementary Particles (Fermions : Spin ½) Families Charge 1 νe νμ ντ 0 Neutrinos Charged 2 - μ- τ- -1 e Leptons 3 u u u c c c t t t 2/3 Quarks 4 d d d s s s b b b -1/3 u = up d = down 6 c = charm Generations 1 2 3 Flavours s = strange t = top b = bottom Vienna1010 22 Fmν ,I Masses of Elementary Particles G J mu , 9 G J Families in units of GeV = 10 eV H M K -9 1 νe (≈0) νμ (≈0) ντ (≈0) < 10 2 e- (5·10-4) μ- (0.105) τ- (1.78) Very hierarchical structure 3 u (3·10-3) c (1.3) t (170) 4 d (6·10-3) s (0.110) b (4.5) Particles in a given family distinguished only by the mass! Vienna1010 23 Interactions between Elementary Particles Mediated by Gauge Bosons (Spin 1) Photon Charge = 0 (QED) (massless) ± W W-Boson Charge = ±1 Electroweak Weak Interactions Interactions (massive) Z0 Z-Boson Charge = 0 80 GeV 91 GeV 8G Ga-Gluons Charge = 0 (QCD) Strong Interactions (a = 1,...8) (massless) Confinement of But carry new “Charge” - Colour Quarks at “Large” (10-15m) scales Vienna1010 24 Feynman Diagrams at Work time - - - e e e νe b t γ W+ W+ e- e- u d u d e- e- t t ti tj Z0 Z0 Gluon νμ νμ u u uk ul Vienna1010 25 The Great Master at Work Richard Feynman Phys. Rev. Bd 76 (1949) 769 Vienna1010 26 More Complicated Feynman Diagrams s d s b s d s b Penguin : Family Z0 γ G H − ν ν μ + μ d d μ + μ − s b s ν Box other + Diagrams box diagrams b s d ν s ν s G Z H Tree s KK s s Diagrams d d d ν b b s s Z´ b b Vienna1010 27 ++ Kus+ = b g K →π νν π + = cudh Penguin Box Still another Penguin Vienna1010 28 Penguin Diagram Vienna1010 29 Penguin Diagram Vienna1010 30 Feynman Diagrams Vienna1010 31 Feynman Diagrams Richard Feynman Vienna1010 32 W d s G Richard Feynman Vienna1010 33 Strength of Interactions ee u u 1 γ α ≈ gluon αQCD ≈ 01() QED 137 e e Sommerfeld‘s d d Strong Interactions Structure Structure Constant Constant dd du uu n p d u α weak 1 W+ −5 ∼ 2 ∼ GF ≅ 110⋅ - at M 2 e low W GeV W- Energies ν e- Fermi Constant e bEGeV≤ 1 g νe At low energies Weak − α weak≈ 4α QED Interactions are weak npe→ νe because of the large mass Weak Structure of W± (similarly for Z0) Constant Vienna1010 34 Gauge Theories: Basic Relativistic Quantum Field Theories with Framework elementary Forces following from Gauge Symmetries Quantum Quantum Quantum Electrodynamics Flavourdynamics Chromodynamics (QED) (QFD) (QCD) Symmetry: Symmetry: U(1)Q Symmetry: SU(3)C SU(2)L⊗ U(1)Y Theory of Unified theory of Theory of electromagnetic weak and electromagnetic strong interactions interactions interactions (also basic for Nuclear Physics) Mediated by Mediated by weak gauge bosons Mediated by ± 0 Photon (g) Photon (g), W Z 8 Gluons (mg= 0) (mg= 0) (80 GeV) (91 GeV) (mG= 0) Vienna1010 35 More Messages from the Attouniverse At very high energies (E ≈ MW, MZ, mt ) 22 supressions 11 /,/ MM WZ not important Weak Interactions as strong as electromagnetic ones. At super high energies (E ≈ 1016 GeV) All interactions could αQCD have the same strength (Grand Unification of Forces) αWeak In a Quantum Field Theory αQED structure constants are E energy dependent Vienna1010 36 Asymptotic Freedom in QCD Bethke hep-ex/0606035 Gross Politzer (1973) Wilczek Nobel Prize 2004 Vienna1010 37 Hierarchical Structure of Quark Flavour-Changing Interactions Cabibbo-Kobayashi-Maskawa matrix Nobel qi qj Prize Vud Vus Vub 2008 = gV W± Weak ij Vcd Vcs Vcb 2 gWeak α = Vtd Vts Vtb Weak 4π (would be a unit matrix for mi=0) Complex Phases (β,γ) u c t -iγ ≈ 1 ≈ 0.2 0.004e responsible for d s b violation of CP Symmetry ≈ -0.2 ≈ 1 0.04 1 2 3 β ≈ 23o 0.008e-iβ -0.04 ≈ 1 Matter – Antimatter γ ≈ 70o Symmetry Vienna1010 38 CKM (Nobel Prize 2008) Dirac Medal (2010) N. Cabibbo M. Kobayashi T. Maskawa (1935-2010) Vienna1010 39 Crucial Question What is the Origin of Particle Masses and the Reason for their Hierarchy and Hierarchy of their Flavour-Changing Interactions ? Explored in the Research Area C of our Universe Cluster Vienna1010 40 But the SU(2)L⊗ U(1)Y Symmetry of the Standard Model implies that W±, Z0, quarks and leptons all should have masses 0 ! Total disaster ! Vienna1010 41 Higgs Mechanism Early 1960´Æ Now Add a system of scalar particles H that causes spontaneous breakdown Breakdown only in vacuum! SU(2)L ⊗ U(1)Y Æ U(1)QED Not in LSM ± 0 Interactions of H with W , Z Many properties of TH remain give MZW0 ≠ 00, M± ≠ while mγ = 0 Interactions of H with quarks and leptons Parametrization of quark and lepton mq ≠≠01 VCKM mass and of ml ≠≠01 VPMNS flavour-changing interactions possible Vienna1010 42 The only Higgs found : Peter Higgs his mass (LEP) mH > 114 GeV but in SM at most 190 GeV Vienna1010 43 Standard Model of Strong and Electroweak Interactions Low Energy Effective Quantum Field Theory based on (< 200 GeV) spontaneously SU(3) ⊗ SU(2) ⊗ U(1) SU(3) ⊗ U(1) C L Y brokenÆ C QED which describes low energy phenomena in terms of 28 Parameters that have to be determined from experiment. The agreement of the Standard Model with the existing experimental data is very impressive Vienna1010 44 But there are Questions ! Where is the Higgs ? How can Higgs mass be protected from becoming How could we reduce the 19 MPlanck ≈ 10 GeV ? number of free parameters ? What is the origin of What is the origin of mass spectrum of different generations ? Quarks and Leptons ? (Why only 3 ?) Are there only How could one unify all 3 + 1 Dimensions ? forces including Gravity ? Matter-Antimatter Dark Matter ? Asymmetry ? Vienna1010 45 Hierarchy (Naturalness) Problem (Quadratic divergences in Higgs mass) 22 mH ~ Λ cut-off through radiative effects Disaster for Λcut-off >> 1 TeV Λcut-off ª ΛPlanck Must fine tune parameters to 34 decimal places to keep mH ~ few 100´s GeV or postulate New Physics at scales 0 (1 TeV) = 103GeV which would remove these divergences ~ 10-19m Vienna1010 46 We need New Physics (new particles and forces) in order to answer all these questions and solve all existing problems ! New Animalcula Vienna1010 47 Complementary Methods to Search for New Physics Direct : Searches Limited by the available Energy Indirect : Quantum Fluctuations Searches (Limited by precision) Vienna1010 48 Direct Search: Production of New Heavy Particles Light Particles proton Complicated proton but calculable process ELHC = 14 TeV Heavy Particle For a Heavy Particle with mass M we need c = 1 at least Epp = M if single produced (t) Epp = 2M if pair produced (tt) Vienna1010 49 Indirect Search: Precision Measurement of Decays of Mesons and Leptons ++ B →τ ντ b ν B+ τ + 2 W Standard g2 Br B++→=τν A W Model diτ SM 2 gW gW M W τ+ u A, B – parameters of a given theory mB ≈ 5 GeV b B+ ντ Contribution ++ + Brdi B → τντ H of a new 2 charged Heavy g2 g2 gH gH =+A W B H τ+ Particle 2 2 u M W MH Signal of a Δ=Br B++ →τν − Br B ++ → τν ≠0 didiττSM new particle Vienna1010 50 Still Large Room for New Physics Standard Model Exp Upper Bound ABCPb s g ≈ 004.
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