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arXiv · 1005.4610

Essence of the vacuum quark condensate

Stanley J. Brodsky·Craig D. Roberts·Robert Shrock·Peter C. Tandy
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Abstract

We show that the chiral-limit vacuum quark condensate is qualitatively equivalent to the pseudoscalar meson leptonic decay constant in the sense that they are both obtained as the chiral-limit value of well-defined gauge-invariant hadron-to-vacuum transition amplitudes that possess a spectral representation in terms of the current-quark mass. Thus, whereas it might sometimes be convenient to imagine otherwise, neither is essentially a constant mass-scale that fills all spacetime. This means, in particular, that the quark condensate can be understood as a property of hadrons themselves, which is expressed, for example, in their Bethe-Salpeter or light-front wavefunctions.

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Stanley J. Brodsky, Craig D. Roberts, Robert Shrock, Peter C. Tandy. 2010-05-25. Essence of the vacuum quark condensate. https://doi.org/10.1103/physrevc.82.022201

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