https://doi.org/10.1051/epjconf/201920602003
QCD strings and the U(1) problem
1
Institute of Advanced Studies, Nanyang Technological University, Singapore
2
School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore
* e-mail: xiongchi@ntu.edu.sg
Published online: 19 April 2019
We promote the usual QCD θ-parameter to a field and interpret it as the phase of the quark condensate, which becomes nontrivial when topological defects, vortices in our formulation, are induced in the quark condensate by the QCD strings (chromoelectric flux tubes). The QCD topological term emerges naturally as a derivative coupling between the Chern-Simons current and a supercurrent in the quark condensate. This new formulation can address the UA(1) problem and leads to the chiral magnetic effects. It is possible that in this formulation the strong CP problem can be avoided without the axion particle.
© The Authors, published by EDP Sciences, 2019
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