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Title: The%202004%20Nobel%20Prize%20in%20Physics


1
The 2004 Nobel Prize in Physics
  • Sourendu Gupta (TIFR)
  • St. Xaviers College, 6/1/2005

2
The people
  • David J. Gross
  • Kavli Institute of Theoretical Physics
  • University of California at Santa Barbara
  • USA
  • (b. 1941)

3
The people
  • H. David Politzer
  • California Institute of Technology
  • USA
  • (b. 1949)

4
The people
  • Frank Wilczek
  • Massachusetts Institute of Technology
  • USA
  • (b. 1951)

5
The prize
  • for the discovery of asymptotic freedom in
    strong interactions

1,300,000
6
The work
  • Gross and Wilczek, Ultraviolet behaviour of
    non-Abelian gauge theories, Physical Review
    Letters, vol 30, p 1343-1346, 1973
  • Politzer Reliable perturbative results for
    Strong Interactions?, Physical Review Letters,
    vol 30, p 1346-1349, 1973

7
Nobel Prizes for theStrong Interactions
  • 2004 Gross, Politzer, Wilczek
  • 1990 Friedman, Kendall, Taylor (DIS)
  • 1982 Kenneth G. Wilson (RG/LGT)
  • 1976 Richter, Ting (J/?)
  • 1969 Murray Gell-Mann (quark model)
  • 1968 Luis Alvarez (hadrons)

8
The two arms of physics
  • Variables what are the things that make up what
    we study analysis
  • Dynamics how do the variables interact and move
    .synthesis

9
Elementary Particles variables
  • 1895 e
  • 1935 e,p,n,?,?
  • Who ordered that? - Rabi
  • 1950 e,p,n,?,?,?,?,?,?,?,?
  • Had I foreseen that, I would have
    gone into botany - Fermi

10
QED
  • Variables are e, ?, ?, ?
  • Dynamics is Maxwells dynamics with quantization
    Dirac, Heisenberg, Bethe (1930s)
  • Theory solved in the 40s (Feynman, Schwinger,
    Tomonaga)
  • Very successful in describing experiments

11
Quantum Hadron Dynamics?
  • Theory of meson baryon interactions was in a
    mess.
  • Yukawa theory (1932)
  • 1960s S-matrix, dual resonance, Regge, string
    theory.
  • Variables were wrong, the dynamics was premature

12
The Eightfold Way (variables)
  • The periodic table of hadrons
  • Building block of hadrons are quarks
  • Mesons contain a quark and an anti-quark, baryons
    have 3 quarks
  • Masses of hadrons are predictions
  • Gell-Mann, Zweig, Nishijima (1953)

13
The Eightfold Way (variables)
14
The Eightfold Way (variables)
15
The Eightfold Way (variables)
16
The Eightfold Way (variables)
17
The era of massive confusion
  • Quark search experiments failed.
  • Idea of confinement quarks live only inside
    hadrons
  • Colour Nambu, Fritzsch, Gell-Mann

18
The crucial experiment
  • Deep inelastic scattering- the Rutherford
    experiment of particle physics
  • First view of quarks
  • Friedman, Kendall, Taylor (1969)
  • Bjorken, Feynman

19
Particles in the Standard Model (1990s)
20
Quantum Chromo-Dynamics the dynamics ofquarks
and gluons
21
Screening in a plasma
22
Effective charge
  • A modification to Coulombs law is the same as a
    distance dependent charge renormalization

23
The bubbling vacuum
  • Quantum fluctuations ????t lt h/2?
  • Particles can be produced from vacuum for a short
    time
  • In a quantum field theory the vacuum bubbles over
    with particles
  • Since it has mobile charges, the vacuum screens

24
Charge renormalization screening in QED
25
Anti-screening in QCD
  • Asymptotic freedom is anti-screening the
    opposite of electrodynamics

26
QCD is born (SLAC to LEP)
  • Asymptotic freedom allowed computation of
    deep-inelastic cross sections, predicted lepton
    pair production, jets, etc
  • many physicists
  • (1970s to 1990s)

27
Open problems for you
  • Does anti-screening in vacuum become screening in
    matter?
  • Are there new phases of matter in xxtreme
    conditions, like a QCD plasma?
  • Relativistic heavy-ion collisions and LGT
  • At long distances charge grows does confinement
    follow?
  • Are there glueballs? New 5q or 6q states?
  • Why is a proton so heavy?
  • Lattice gauge theory

28
Where it all connects
  • High temperature matter early in the history of
    the universe
  • High density matter in neutron stars and other
    supernova remnants

29
The RHIC at Brookhaven
30
The CRAY in TIFR
31
Thank You
32
How good is QCD?
33
How good is QCD?
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