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Concerning the quark condensate

K. Langfeld·R. Pullirsch·H. Markum·C. D. Roberts·S. M. Schmidt
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Abstract

A continuum expression for the trace of the massive dressed-quark propagator is used to explicate a connection between the infrared limit of the QCD Dirac operator's spectrum and the quark condensate appearing in the operator product expansion, and the connection is verified via comparison with a lattice-QCD simulation. The pseudoscalar vacuum polarisation provides a good approximation to the condensate over a larger range of current-quark masses.

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K. Langfeld, R. Pullirsch, H. Markum, C. D. Roberts, S. M. Schmidt. 2003-01-08. Concerning the quark condensate. https://doi.org/10.1103/physrevc.67.065206

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