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北京 , 2002. 5. 19.

http://pony2.ihep.ac.cn/~besr/ppt/hepintro.ppt. 迷人的高能物理. 1. 物质结构：宏观与微观. 2. 我们从高能物理知道什么？. 3. 北京谱仪上的研究工作. 2002 National Science Week. 中国科学院高能物理研究所 , 黄光顺. 北京 , 2002. 5. 19. 什么是高能物理？. 高能物理又称粒子物理，是研究物质的基本组元和它们之间相互作用规律的一门学科。 高能是指研究粒子物理需要高能加速器实验手段，能量一般大于 1 GeV ( 10 9 电子伏 ) 。

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北京 , 2002. 5. 19.

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  1. http://pony2.ihep.ac.cn/~besr/ppt/hepintro.ppt 迷人的高能物理 1. 物质结构：宏观与微观 2. 我们从高能物理知道什么？ 3. 北京谱仪上的研究工作 2002 National Science Week 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  2. 什么是高能物理？ • 高能物理又称粒子物理，是研究物质的基本组元和它们之间相互作用规律的一门学科。 • 高能是指研究粒子物理需要高能加速器实验手段，能量一般大于 1 GeV (10 9电子伏)。 • 高能物理研究的内容涉及到基本的物质结构及其相互作用规律，因而在人们认识世界和改造世界过程中起到很大作用。 • 她始终处于科学的前沿。 • 她总结出的“标准模型”是物理的基础。 • 她把人们的认识水平推进到 10 –19 米。 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  3. Large structures and Orders of Magnitude 地 球 10 7 m (10000000米) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  4. Sun(Eclipse) corona 10 9 m Sun ≈ 2x1030 kg ≈ 1057 (protons + neutrons) nucleons 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  5. Earth Orbit 10 11 m 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  6. Milky Way (银河系) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  7. Spiral Galaxy 100 000 light years = 10 21 m 10 11 stars 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  8. Spiral Galaxy 100 000 light years = 10 21 m 10 11 stars 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  9. Hubble Deep Field 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  10. A Foamy Universe (bubbles 200 Mly across) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  11. Summary of the largest structures 10 21 m 10 22 m 10 23 m 10 11 galaxies 10 22 stars 1080 nucleons 10 24 m 10 25 m 10 26 m 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  12. 客体尺度与观测手段 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  13. Our Universe Dominated by Matter and Gravity ** (1011 galaxies, 1022 stars) Described by General Relativity (or Newtonian Mechanics) ** This is far from the whole truth !! 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  14. Big Bang:宇宙的起源 15 billions = 1.5 x 10 12 years ago and since then ever expanding Where it all came from 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  15. Will the Expansion ever stop ? Inflation predicts a flat universe. This means that the Density of Matter and Energy equals the so called critical density Ordinary Matter can account for only up to 5% of the critical density Dark Matter Problems 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  16. Need a spherical halo of matter around the galaxy The First Dark Matter problem: these Galaxies should simply not exist ! So: is there invisible (dark) matter around the galaxy ? 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  17. measured speed 200km/s predicted distance from center 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  18. Gravitational lensing Distant galaxy 109 light years Foreground cluster 2x 109 light years Observer 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  19. Large amounts of invisible (dark) matter Can NOT be ordinary matter : - does not interact with light - does not interact with ordinary matter - does concentrate around galaxies and in galaxy clusters. What is it ??? If the answer is Super Symmetric Particles, How can we find it? LHC !! 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  20. The Second Dark Matter problem: The dark matter seems to make up only 30-50% of the critical density This may be linked with observations of a possible accelerating expansion of the universe at large distances. Study of type 1a Supernovae (1a Supernovae ≈ standard light sources) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  21. 1a Supernova: white dwarf accompanying star 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  22. Far away* supernovae seem to be too far away ! Very difficult observations, but if true could mean: Resurrection of Einstein’s Cosmological Constant, or “Qintessence” - one more possibility of Exotic Matter ???? Need more astronomical data Need more powerful accelerator for a better understanding of dark matter * for specialists - red shifts z ≈ 1 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  23. Matter What happened to the Anti Matter ? Anti Matter 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  24. 物质的组成单元 Electrons (10-18 m ) 电子 see Atom nucleus nucleon quark 原子 核子(质子,中子) 核子 夸克 10-10 m 10-14 m 10-15 m 10-18 m 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  25. 有“味道”和“颜色”的夸克 六味 三色 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  26. Ingredients of the Standard Model To explain all matter we needthree generationsof quarks We also havethree generationsof leptons. THE COMPLETE PICTURE: Quarks Leptons charges: 2/3 -1/3 0 -1 updown neelectron (e) charmstrange nmmuon (m) topbottomnttau (t) Two different sorts of Matter particles: -composite particles made up of quarks (called HADRONS) -non composite particles like electrons and neutrinos (LEPTONS) 粒子物理标准模型 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  27. “Fundamental” Matter Particles heavier Charge +2/3 t u c quarks (q) s b d -1/3 nm ne nt 0 leptons e m t -1 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  28. Stable (ordinary) matter: one up quark (charge +2/3) one down quark (charge -1/3) one electron (charge -1) leptons one neutrino (no charge, “no” mass) proton composite particles nucleons neutron But for what do we need the neutrino?? 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  29. Can not use light microscopes to study atoms !!! Quantum mechanics tells us that particles behave like waves and visa versa: electron l =h/p Use electron microscopes 为什么需要加速器？ 高能加速器是威力巨大的 ”电子显微镜“ 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  30. High Energy electron-proton scattering quark electron New Stuff fromE=Mc2 New, unstable particles, can NOT be explained as made up of up and down quarks only. 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  31. Einstein:E = Mc2 use units such that c =1 E (GeV or MeV) p (GeV/c or MeV/c) M (GeV/c2 or MeV/c2) Special Relativity: ( E2= (pc)2 + (M0c2)2 ) pc E Mproton = 0.931 GeV/c2 ≈ 1 GeV/c2 Melectron = 0.5 MeV/c2 ( Mtop = 170 GeV/c2 ) M0c2 proton diameter = length scale: 10-15 m = 1 fermi (femtometer) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  32. Creating New Matter with Accelerator Need two more generations of quarks 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  33. Practical Units U=1 eV = 1.6x10-19J (speed at positive plate 18 000 km/s) electron (energy U) 1 keV = 103 eV 1 MeV = 106 eV 1 GeV = 109 eV 1 TeV = 1012 eV BEPC = 3 GeV LEP = 209 GeV LHC = 14 TeV - + 1 Volt 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  34. 自然界中的四种相互作用 强作用 重力 弱作用 电磁作用 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  35. Forces of Nature name of field (wave)force carrier (particle) gravitational field graviton (?) electromagnetic field (a)g(photon) weak field Z0, W+, W- strong (color) field 8 gluons, g higgs field (*) h0, H0, H+, H-.. (*)Unifying the weak and the electromagnetic fields giving mass to the Z and the W’s - all other particles !!! (a) Electric and Magnetic Fields Unified by Maxwell (1864) Big Question: Can all Force Fields be unified ? (*) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  36. Higgs粒子存在吗？ How the forces work the Strong Field (gluons)couple toQuarks the Weak field (W’s and Z)couple toLeptons the Electromagnetic fieldcouple toCharge (classical: F = qE) the Gravitational fieldcouple toMass (Newton: F = mg) the Higgs field couple to Mass ! ! ! In fact the Higgs field is responsible for the mass ! Can detailed studies of large number of Higgs Particles give us the explanation why we have three families of quarks and leptons, and why they have such enormous mass differences ?? 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  37. Composite Matter Particles(hadrons) made out of quarks ( q ) and anti quarks ( q ) hadrons Baryons Mesons q q q q q Anti Baryons Hundreds of possible combinations orparticles q q q 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  38. Higgs Hunting with LEP (Total energy 206.6 GeV) (e- + e+) -----> (Z0 + H) -----> 4 jets two Higgs jets containing B-particles two Z jets H (115 GeV) e- e+ Z (91 GeV) 2.5 s effect for a Higgs Particle at 115 GeV 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  39. ALEPH DELPHI 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  40. How the forces vary with distance Classical electrostatics (Coulomb’s law): F =k (q1 q2)/r2 Classical gravitation (Newton): F =g(M1 M2)/r2 In a quantum field theory the “constants” k and g will vary with energy (Vacuum Polarization) Is it possible that all the forces of Nature have the same strength at a certain (very high) energy? 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  41. The “strength” of the strong force (running of the Coupling “Constant” aS) 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  42. Unification of the Coupling Constants in the SM and the minimal MSSM 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  43. Unification of Gravity with the other forces From a simple extrapolation this should happen at an energy scale of 1019 GeV or a length scale of 10-35 m But only superstring theory is capable of unifying all the forces. Superstring theory contains supersymmetry. Superstrings are objects with 1 spatial dimension moving in a world of 9, but where all but three dimensions are curled up on an unobservable scale ! The # of dim. for the EM field is tested to be 3 down to 10-18 m, but gravity is tested only down to mm scale ! ! Is unification of all the forces possible at the TeV scale ? 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  44. How many macroscopic dimensions can we “see”? In N dimensions: field lines spread out, i.e. field weakens as 1/rN-1 gravitation and light (electromagnetism) tell us: three macroscopic dimensions 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  45. 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  46. Strings and extra dimensions: Extra Dimension Graviton . . . . Two-dimensional (“normal”) Space Particles as Super Strings 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  47. Parallel universes gravity curled up at millimeter scale Gravity from galaxy on neighboring sheet may be weakly felt 1 mm 1 mm billions of light years 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  48. One universe (folded) Gravity from galaxy on neighboring sheet (mm distance ) can be weakly felt. Light has to go billions of light years. 1 mm 1 mm billions of light years 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  49. 高能加速器和探测器规模巨大 欧洲核子中心LEP/LHC储存环直径 9 公里！ 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

  50. 建造中的ATLAS探测器 中国科学院高能物理研究所, 黄光顺 北京, 2002. 5. 19.

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