Finite Temperature Field Theory
                   (Physics 880.20, Spring 2010, course web page)

   Course  objective: Finite temperature or thermal field theory refers to the formulation of relativistic quantum field theory in a dense media. This is somewhat different from the usual vacuum field theory which mostly deals with the outcome of the scattering of asymptotically prepared states in vacuum. Most of this course will deal with the path integral approach to describe the various static properties and response to external currents of extended systems of scalars, spinors and vector gauge fields held at a fixed high temperature. This will include both the imaginary time and the real time formalisms. This will be followed by an extended study of finite temperature QCD and the set up of the gauge invariant theory of hard thermal loops. This will be followed by extensions of the theory to mildly non-equilibrium phenomena and a set of applications to high energy heavy-ion collisions.
                                                                      

   
Classes will be from 2:30 to 4:18, Tuesdays and Thursdays in M2015.

    Course Textbook: Finite Temperature Field Theory, Principles and
                                     Applications by J. Kapusta & C. Gale,
                                     textbook web page@ Cambridge university press

                                     Note: this is the most recent textbook on the subject and contains a large amount of the topics
                                     that I intend to cover. However, it does not cover everything and so this will be supplemented
                                     by at least two other texts and a handful of research papers. I will provide a list of papers
                                     soon and a set of notes as the course progresses along.


      Other books: Thermal Field Theory by M. Le Bellac  @ Cambridge university press
                             Finite temperature field theory by A. Das. @ World Scientific
     

      then there are the classics: Fetter and Walecka, Baym and Kadanoff and Abrikosov, Gorkov and Dzyaloshinskii
      (these are all non-relativistic but still useful for many basic techniques).


      Lecture Notes and Home Work


      Relevant papers: (note these are only those papers whose content is not completely included in the textbooks but will be used in the course)

Real and Imaginary Time Field Theory at Finite Temperature and Density.   N.P. Landsman, C.G. van Weert, (Amsterdam U.) . ITFA-86-12, Sep 16, 1986. (Received Sep 1986). 205pp.  Published in Phys.Rept.145:141,1987.

Determination of Thermodynamic Green's Functions Gordon Baym and N. David Mermin. J. Math. Phys. 2, 232 (1961)

Simple Rules for Discontinuities in Finite Temperature Field Theory.  H.Arthur Weldon, (Pennsylvania U.) . PRINT-83-0452 (PENN), Jun 1983. (Received Jun 1983). 30pp. Published in Phys.Rev.D28:2007,1983.

Vector dominance model at finite temperature. Charles Gale, (McGill U.) , Joseph I. Kapusta, (Minnesota U.) . MCGILL-90-57, Nov 1990. 27pp.  Published in Nucl.Phys.B357:65-89,1991.

Reformulation of finite temperature dilepton production.  H.A. Weldon, (West Virginia U.) . 1990. Published in Phys.Rev.D42:2384-2387,1990.

Production Of Soft Dileptons In The Quark - Gluon Plasma.  Eric Braaten, (Northwestern U.) , Robert D. Pisarski, (Brookhaven) , Tzu-Chiang Yuan, (Northwestern U.) . BNL-43941, NUHEP-TH-90-1, Jan 1990. 16pp.  Published in Phys.Rev.Lett.64:2242,1990.                             

High-energy photons from quark - gluon plasma versus hot hadronic gas.  Joseph I. Kapusta, P. Lichard, D. Seibert, (Minnesota U.) . 1991.  Published in Phys.Rev.D44:2774-2788,1991, Erratum-ibid.D47:4171,1993.

Two loop selfenergy and multiple scattering at finite temperature. Joseph I. Kapusta, (Minnesota U.) , S.M.H. Wong, (Ohio State U.) . NUC-MINN-2001-4-T, Feb 2001. 13pp. Published in Phys.Rev.D64:045008,2001.  e-Print: hep-th/0103065

On the imaginary parts and infrared divergences of two loop vector boson selfenergies in thermal QCD.
A. Majumder, Charles Gale, (McGill U.) . Nov 2001. 34pp.
Published in Phys.Rev.C65:055203,2002. e-Print: hep-ph/0111181

Energy loss of a heavy quark in the quark - gluon plasma. Eric Braaten, (Northwestern U.) , Markus H. Thoma, (LBL, Berkeley) . LBL-30998, NUHEP-TH-91-14, Jul 1991. 14pp.  Published in Phys.Rev.D44:2625-2630,1991.

Elastic energy loss and longitudinal straggling of a hard jet. A. Majumder, (Duke U. & Ohio State U.) . Oct 2008. (Received Sep 2009). 5pp.  Published in Phys.Rev.C80:031902,2009.  e-Print: arXiv:0810.4967 [nucl-th]

Quark - Gluon Transport Theory. Part 1. the Classical Theory.
  Ulrich W. Heinz, (Frankfurt U.) . UFTP-135-1984, Jun 1984. (Received Jun 1984). 46pp.  Published in Annals Phys.161:48,1985.

Quark - Gluon Transport Theory. Part 2. Color Response And Color Correlations In A Quark - Gluon Plasma. 
Ulrich W. Heinz, (Brookhaven) . BNL-36721, Jul 1985. (Received Jul 1985). 55pp.  Published in Annals Phys.168:148,1986.

Classical transport theory and hard thermal loops in the quark - gluon plasma. P.F. Kelly, Q. Liu, C. Lucchesi, C. Manuel, (MIT, LNS) . MIT-CTP-2320, Jun 1994. 23pp.  Published in Phys.Rev.D50:4209-4218,1994. e-Print: hep-ph/9406285

Effective theories for real time correlations in hot plasmas.  Peter Brockway Arnold, (Virginia U.) , Laurence G. Yaffe, (Washington U., Seattle) . UW-PT-97-22, Sep 1997. 28pp.  Published in Phys.Rev.D57:1178-1192,1998. e-Print: hep-ph/9709449

Transport coefficients in high temperature gauge theories. 1. Leading log results. Peter Brockway Arnold, (Virginia U.) , Guy D. Moore, Laurence G. Yaffe, (Washington U., Seattle) . UW-PT-00-15, Oct 2000. 41pp.
Published in JHEP 0011:001,2000.  e-Print: hep-ph/0010177

      Tentative Course outline (this could change depending on how things go):

                              1) Review of Thermodynamics and Statistical Mechanics.

                              2) Path integrals in vacuum for a free scalar field.

                              3) The partition function of a free scalar field as a path integral and Matsubara frequencies.

                              4) Interactions in phi^4 theory and Feynman rules in imaginary time.

                              5) The imaginary time propagator, self-energy, Schwinger-Dyson equation.

                              6) Higher orders, resummation and breakdown of perturbation theory.

                              7) The partition function for free fermions, chemical potentials and non-covariant propagators.

                              8) The partition function for free gauge bosons, gauge invariance and ghosts.

                              9) Linear response, real time correlators and spectral density.

                              10) Subtleties in analytic continuation to real energies and Carlmann's theorem.

                              11) Applications: in-medium dispersion relations, space-like and time-like modes,

                              12) Imaginary parts of self-energies, cutting rules, physical interpretation.

                              13) Real time formalism, propagators and self-energies.

                              14) QED at finite temperature, self-energies and hard thermal loops (HTL).

                              15) Dispersion relations, dynamical mass generation, Debye screening, Landau damping.
                             
                              16) QCD at finite temperature,  HTL self-energies and vertices.

                              17) Gauge invariance of HTL QCD and the gluon damping rate.
 
                              18) Applications 1: Hard quark elastic energy loss.
                          
                              19) Applications 2: Dilepton and real photon production from a Quark Gluon Plasma.

                              20) Introduction to the Boltzmann-Vlasov equation,
                                     rederivation of HTL theory from the Vlasov equation

Possible extra topics: If we get this far, the remaining topics will be covered at a more colloquial level

                              21) Collision term at  Leading log and  transport coefficients.

                              22) Outstanding issues: magnetic screening, Linde's problem.

                              23) Collision term at Leading order, the Arnold-Moore-Yaffe resummation.

                              24) Symmetry breaking at finite temperature and density, and Anomalies.

                              25) Restoration of spontaneously broken symmetries at finite temperatures.

                              26) Simple hadronic theories at finite temperature, vector dominance.

                              27) Renormalization at finite temperature.