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QCD and Asymptotic Freedom: Perspectives and Prospects

Frank Wilczek
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Abstract

QCD is now a mature theory, and it is possible to begin to view its place in the conceptual universe of physics with appropriate perspective. There is a certain irony in the achievements of QCD. For the problems which initially drove its development only limited insight has been achieved. However I shall argue that QCD is actually {\it more\/} special and important a theory than one had any right to anticipate. After elaborating these quasi-philosophical remarks, I discuss two current frontiers of physics that illustrate the continuing vitality of the ideas. The recent wealth of beautiful precision experiments measuring the parameters of the standard model has made it possible to consider the unification of couplings in unprecedented quantitative detail. One central result emerging from these developments is a tantalizing hint of virtual supersymmetry. The possibility of phase transitions in matter at temperatures of order $\sim 10^2 Mev$, governed by QCD dynamics, is of interest from several points of view. There is the interesting possibility of long-range correlations in heavy ion collisions due to the creation of large regions of misaligned chiral condensate. Opening Talk at the Aachen conference, ``20 Years of QCD'', June 1992.

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Frank Wilczek. 1992-11-20. QCD and Asymptotic Freedom: Perspectives and Prospects. https://doi.org/10.1142/s0217751x93000564

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