Suggested Course Layout

1. Suggested Course Layout • Move class from 3 days a week to 2 days a week Proposal: Mo 2-4 p.m., Tu 11 a.m.-1 p.m. • Jan8,9: week1 – Intro and kinematic variables • Jan15,16: Bormio Winter Workshop, no class • Jan 22,23: weeks 2 & 3 – Spacetime evolution of asymptotic freedom • Jan 29,30: week 4 – thermal and hydromodels • Feb 5,6: week 5 – pQCD in QGP physics • Feb 12,13: Big Sky Winter Workshop, no class • Feb 19,20: week 6 – lattice QCD • Feb 26,27: weeks 7 & 8 – initial conditions and complete modeling • Mar 5,6: week 9 – bulk signatures and properties • Mar 12,13: Spring Break, no class • Mar 19,20: week 10 – rare particle production • Mar 26,27: week 11 – high momentum probes • Apr 2,3: week 12 – RHIC and its detectors • Apr, 9,10: week 13 – essays (I) • Apr 16,17: week 14 – essays (II) • Apr 23: overflow

2. Motivation for Relativistic Heavy Ion Collisions Two big connections: cosmology and QCD

3. The phase diagram of QCD Early universe quark-gluon plasma critical point ? Tc Temperature colour superconductor hadron gas nucleon gas nuclei CFL r0 Neutron stars vacuum baryon density

4. Evolution of Forces in Nature

5. Going back in time… Age Energy Matter in universe 0 1019 GeV grand unified theory of all forces 10-35 s 1014 GeV 1st phase transition (strong: q,g + electroweak: g, l,n) 10-10 s 102 GeV2nd phase transition (strong: q,g + electro: g + weak: l,n) 10-5 s 0.2 GeV 3rd phase transition (strong:hadrons + electro:g + weak: l,n) 3 min. 0.1 MeVnuclei 6*105 years0.3 eVatoms Now3*10-4 eV = 3 K (15 billion years) RHIC, LHC & FAIR RIA & FAIR

6. Connection to Cosmology • Baryogenesis ? • Dark Matter Formation ? • Is matter generation in cosmic medium (plasma) different than matter generation in vacuum ?

7. Sakharov (1967) – three conditions for baryogenesis • Baryon number violation • C- and CP-symmetry violation • Interactions out of thermal equilibrium • Currently, there is no experimental evidence of particle interactions where the conservation of baryon number is broken: all observed particle reactions have equal baryon number before and after. Mathematically, the commutator of the baryon number quantum operator with the Standard Model hamiltonian is zero: [B,H] = BH - HB = 0. This suggests physics beyond the Standard Model • The second condition — violation of CP-symmetry — was discovered in 1964 (direct CP-violation, that is violation of CP-symmetry in a decay process, was discovered later, in 1999). If CPT-symmetry is assumed, violation of CP-symmetry demands violation of time inversion symmetry, or T-symmetry. • The last condition states that the rate of a reaction which generates baryon-asymmetry must be less than the rate of expansion of the universe. In this situation the particles and their corresponding antiparticles do not achieve thermal equilibrium due to rapid expansion decreasing the occurrence of pair-annihilation.

8. Dark Matter in RHI collisions ? Possibly (not like dark energy) The basic parameters: mass, charge

9. Basic Thermodynamics Hot Sudden expansion, fluid fills empty space without loss of energy. dE = 0 PdV > 0 thereforedS > 0 Hot Hot Gradual expansion (equilibrium maintained), fluid loses energy through PdV work. dE = -PdV thereforedS = 0 Hot Isentropic Adiabatic Cool

10. Nuclear Equation of State

11. Nuclear Equation of State

12. Golden Rule 2: All entropy is in relativistic species Expansion covers many decades in T, so typically either T>>m (relativistic) or T<<m (frozen out) Golden Rule 1: Entropy per co-moving volume is conserved Golden Rule 3: All chemical potentials are negligible Golden Rule 4:

13. 1 Billion oK 1 Trillion oK g*S Start with light particles, no strong nuclear force

14. 1 Billion oK 1 Trillion oK g*S Previous Plot Now add hadrons = feel strong nuclear force

15. 1 Billion oK 1 Trillion oK g*S Previous Plots Keep adding more hadrons….

16. How many hadrons? Density of hadron mass states dN/dM increases exponentially with mass. Broniowski, et.al. 2004 TH ~ 21012oK Prior to the 1970’s this was explained in several ways theoretically Statistical Bootstrap Hadrons made of hadrons made of hadrons… Regge TrajectoriesStretchy rotators, first string theory

17. Rolf Hagedorn German Hadron bootstrap model and limiting temperature (1965) Ordinary statistical mechanics For thermal hadron gas (somewhat crudely): Energy diverges as T --> TH Maximum achievable temperature? “…a veil, obscuring our view of the very beginning.” Steven Weinberg, The First Three Minutes (1977)

18. D. Gross QCD to the rescue! H.D. Politzer F. Wilczek Replace Hadrons (messy and numerous) by Quarks and Gluons (simple and few) American QCD Asymptotic Freedom (1973) e/T4  g*S Thermal QCD ”QGP”(Lattice) “In 1972 the early universe seemed hopelessly opaque…conditions of ultrahigh temperatures…produce a theoretically intractable mess. But asymptotic freedom renders ultrahigh temperatures friendly…” Frank Wilczek, Nobel Lecture (RMP 05) Hadron gas Karsch, Redlich, Tawfik, Eur.Phys.J.C29:549-556,2003

19. Nobel prize for Physics 2005 “Before [QCD] we could not go back further than 200,000 years after the Big Bang. Today…since QCD simplifies at high energy, we can extrapolate to very early times when nucleons melted…to form a quark-gluon plasma.” David Gross, Nobel Lecture (RMP 05) g*S Thermal QCD -- i.e. quarks and gluons -- makes the very early universe tractable; but where is the experimental proof? n Decoupling Nucleosynthesis e+e- Annihilation Heavy quarks and bosons freeze out QCD Transition Mesons freeze out Kolb & Turner, “The Early Universe”

20. The main features of Quantum Chromodynamics (QCD) • Confinement • At large distances the effective coupling between quarks is large, resulting in confinement. • Free quarks are not observed in nature. • Asymptotic freedom • At short distances the effective coupling between quarks decreases logarithmically. • Under such conditions quarks and gluons appear to be quasi-free. • (Hidden) chiral symmetry • Connected with the quark masses • When confined quarks have a large dynamical mass - constituent mass • In the small coupling limit (some) quarks have small mass - current mass

21. Quarks and Gluons

22. Basic Building Blocks ala Halzen and Martin

23. Quark properties ala Wong

24. What do we know about quark masses ? Why are quark current masses so different ? Can there be stable (dark) matter based on heavy quarks ?

25. Elementary Particle Generations

26. Some particle properties

27. Elemenary particles summary

28. Comparing QCD with QED (Halzen & Martin)

29. Quark and Gluon Field Theory == QCD (I)

30. Quark and Gluon Field Theory == QCD (II)

31. Quark and Gluon Field Theory == QCD (III) • Boson mediating the q-qbar interaction is the gluon. • Why 8 and not 9 combinations ? (analogy to flavor octet of mesons) • R-Bbar, R-Gbar, B-Gbar, B-Rbar, G-Rbar, G-BBar • 1/sqrt(2) (R-Rbar - B-Bbar) • 1/sqrt(6) (R-Rbar + B-Bbar – 2G-Gbar) • Not: 1/sqrt(3) (R-Rbar + G-Gbar + B-Bbar) (not net color)

32. Hadrons

33. QCD – a non-Abelian Gauge Theory

34. Particle Classifications

35. Quarks

36. Theoretical and computational (lattice) QCD In vacuum: - asymptotically free quarks have current mass - confined quarks have constituent mass - baryonic mass is sum of valence quark constituent masses Masses can be computed as a function of the evolving coupling Strength or the ‘level of asymptotic freedom’, i.e. dynamic masses. But the universe was not a vacuum at the time of hadronization, it was likely a plasma of quarks and gluons. Is the mass generation mechanism the same ?

37. Confinement Represented by Bag Model

38. Bag Model of Hadrons

39. Comments on Bag Model

40. Still open questions in the Standard Model

41. Why RHIC Physics ?

42. Why RHIC Physics ?