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Quantum Field Theory (QFT)

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Part of the book series: Fundamental Theories of Physics ((FTPH,volume 190))

Abstract

This chapter outlines (special-relativistic) quantum field theory, with particular emphasis on the roles played therein by time and background dependence. (Fully understanding this chapter rather probably requires having studied at least an elementary course in quantum field theory.) In particular, the current chapter shows that the Wightman axioms for quantum field theory are replete with temporal and background dependent concepts. The Lorentz group, upon which quantum field theory’s equations for each spin of particle rest, is also a background-dependent concept.

While there is some interesting contrast with the previous chapter’s account of time in nonrelativistic quantum theory, the main point of this chapter’s exposition is the differences between it and how time is conceived of in general relativity (Chaps. 7 and 8). These differences are essential preliminary reading before tackling both Chapter 11’s introduction to Quantum Gravity and Chaps. 9, 10 and 12’s introduction to this book’s main topic of the Problem of Time and its Background Independence underpinning. The current chapter also contains this book’s quantum exercises.

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Notes

  1. 1.

    If unfamiliar with any of the non-temporal material in this Chapter, consult [712]; some of this Chapter’s material on time in QFT (and the Wightman axioms) may however be new to the reader.

  2. 2.

    If insufficiently familiar with Green’s functions (named after 19th century mathematician George Green), consult [220]. In contrast to propagators, correlators are Green’s functions corresponding to time-independent wave equations. Finally, examples of choices of contour used in defining propagators are retarded, advanced, Feynman and ‘anti-Feynman’ propagators, after noted physicist Richard Feynman. The retarded case is causal and the advanced case is anti-causal; The most usual choice for propagators is the Feynman propagator, which is the half-causal half-anticausal choice, with matter treated causally and antimatter treated anti-causally.

  3. 3.

    The capital Latin indices here run over 1 to 4 for 4-component spinor indices; these spinorial indices are often suppressed in this book.

  4. 4.

    By the half-causal half-anticausal choice in the Feynman propagators, some of the arrows in Feynman diagrams (Fig. 6.1.b) point backwards. This corresponds to modelling distinguishable antiparticles as if they were travelling backward in time. This convention moreover indeed works for practical purposes.

  5. 5.

    In this book, we use overhead arrows to denote 4-vector quantities.

  6. 6.

    QFT does not by itself entail SR, e.g. phonons are a Nonrelativistic QFT model of quanta of sound waves in materials.

  7. 7.

    Moreover, the Wightman axioms (named after mathematical physicist Arthur Wightman) do not cover Quantum Gauge Theories. See e.g. [269] for a recent overview of this, and also [687] as regards an advanced consideration of their Euclidean counterpart.

  8. 8.

    Appendix O outlines ‘distributions’ in the current sense of Functional Analysis. So as to not confuse this with ‘probability distribution’ or ‘distribution of matter’, this book always fully spells out these other uses.

  9. 9.

    I.e. physicist Murray Gell-Mann’s eightfold way explanation of the octet, singlet and decuplet patterns of the observed and predicted-and-confirmed hadrons [886].

References

  1. Alvarez-Gaumé, L., Witten, E.: Gravitational anomalies. Nucl. Phys. B 234, 269 (1984)

    Article  ADS  MathSciNet  Google Scholar 

  2. Audoin, C., Guinot, B.: The Measurement of Time. Time, Frequency and the Atomic Clock. Cambridge University Press, Cambridge (2001)

    Google Scholar 

  3. Bertlmann, R.A.: In: Anomalies in Quantum Field Theory. Clarendon, Oxford (1996)

    Google Scholar 

  4. Bohr, N., Rosenfeld, L.: Zur Frage des Messbarkeit der Electromagnetischen Feldgrössen [On the question of measurability of the electromagnetic field quantities]. K. Dan. Vidensk. 78, 94 (1933)

    Google Scholar 

  5. Courant, R., Hilbert, D.: Methods of Mathematical Physics, vols. 1 and 2. Wiley, Chichester (1989)

    Book  MATH  Google Scholar 

  6. DeWitt, B.S.: Quantum theory of gravity. II. The manifestly covariant theory. Phys. Rev. 160, 1195 (1967)

    Article  ADS  MATH  Google Scholar 

  7. DeWitt, B.S.: Quantum theory of gravity. III. Applications of the covariant theory. Phys. Rev. 160, 1239 (1967)

    Article  ADS  MATH  Google Scholar 

  8. Dirac, P.A.M.: Lectures on Quantum Mechanics. Yeshiva University, New York (1964)

    MATH  Google Scholar 

  9. Duncan, A.: The Conceptual Framework of Quantum Field Theory. Oxford University Press, London (2012)

    Book  MATH  Google Scholar 

  10. Feynman, R.P. (lecture course given in 1962–1963), published as Feynman, R.P., Morinigo, F.B., Wagner, W.G., Hatfield, B. (eds.): Feynman Lectures on Gravitation. Addison–Wesley, Reading (1995)

    Google Scholar 

  11. Geroch, R.P.: General Relativity from A to B. University of Chicago Press, Chicago (1978)

    Google Scholar 

  12. Giulini, D.: The superspace of geometrodynamics. Gen. Relativ. Gravit. 41(785), 785 (2009). arXiv:0902.3923

    Article  ADS  MathSciNet  MATH  Google Scholar 

  13. Giulini, D., Joos, E., Kiefer, C., Kupsch, J., Stamatescu, I.-O., Zeh, H.D.: Decoherence and the Appearance of a Classical World in Quantum Theory. Springer, Berlin (1996)

    Book  MATH  Google Scholar 

  14. Haag, R.: Local Quantum Physics. Springer, Berlin (1992)

    Book  MATH  Google Scholar 

  15. Heisenberg, W., Pauli, W.: Zer Quantendynamik der Wellenfelder [Quantum dynamics of wave fields]. Z. Phys. 56, 1 (1929)

    Article  ADS  MATH  Google Scholar 

  16. Isham, C.J.: An introduction to quantum gravity. In: Isham, C.J., Penrose, R., Sciama, D. (eds.) Oxford Symposium on Quantum Gravity. Clarendon, Oxford (1975)

    Google Scholar 

  17. Isham, C.J.: Canonical quantum gravity and the problem of time. In: Ibort, L.A., Rodríguez, M.A. (eds.) Integrable Systems, Quantum Groups and Quantum Field Theories. Kluwer Academic, Dordrecht (1993). gr-qc/9210011

    Google Scholar 

  18. Isham, C.J.: Lectures on Quantum Theory. Imperial College Press, London (1995)

    Book  MATH  Google Scholar 

  19. Jammer, M.: The Philosophy of Quantum Mechanics. Wiley, New York (1974)

    Google Scholar 

  20. Jammer, M.: Concepts of Simultaneity. From Antiquity to Einstein and Beyond. Johns Hopkins University Press, Baltimore (2006)

    Google Scholar 

  21. Landau, L.D., Lifshitz, E.M.: Quantum Mechanics. Pergamon, New York (1965)

    MATH  Google Scholar 

  22. Muga, G., Sala Mayato, R., Egusquiza, I. (eds.): Time in Quantum Mechanics, vol. 1. Springer, Berlin (2008)

    Google Scholar 

  23. Muga, G., Sala Mayato, R., Egusquiza, I. (eds.): Time in Quantum Mechanics, vol. 2. Springer, Berlin (2010)

    Google Scholar 

  24. Osterwalder, K., Schrader, R.: Axioms for Euclidean Green’s functions II. Commun. Math. Phys. 42, 281 (1975)

    Article  ADS  MathSciNet  MATH  Google Scholar 

  25. Peskin, M.E., Schroeder, D.V.: An Introduction to Quantum Field Theory. Perseus Books, Reading (1995)

    Google Scholar 

  26. Rindler, W.: Relativity. Special, General and Cosmological. Oxford University Press, Oxford (2001)

    MATH  Google Scholar 

  27. Streater, R.F., Wightman, A.S.: PCT, Spin and Statistics, and All That. Benjamin, New York (1964)

    MATH  Google Scholar 

  28. The ATLAS Collaboration: Observation of a new particle in the search for the standard model Higgs boson with the ATLAS detector at the LHC. Phys. Lett. B 716, 1 (2012)

    Article  ADS  Google Scholar 

  29. Wald, R.M.: The formulation of quantum field theory in curved spacetime. In: Rowe, D. (ed.) Proceedings of the ‘Beyond Einstein Conference’. Birkhäuser, Boston (2009). arXiv:0907.0416

    Google Scholar 

  30. Weinberg, S.: The Quantum Theory of Fields. Vol. I. Foundations. Cambridge University Press, Cambridge (1995)

    Book  Google Scholar 

  31. Weinberg, S.: The Quantum Theory of Fields. Vol. II. Modern Applications. Cambridge University Press, Cambridge (1995)

    Book  Google Scholar 

  32. Weinberg, S.: Cosmology. Oxford University Press, New York (2008)

    MATH  Google Scholar 

  33. Zeh, H.D.: The Physical Basis of the Direction of Time. Springer, Berlin (1989)

    Book  Google Scholar 

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Anderson, E. (2017). Quantum Field Theory (QFT). In: The Problem of Time. Fundamental Theories of Physics, vol 190. Springer, Cham. https://doi.org/10.1007/978-3-319-58848-3_6

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