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arXiv · 1512.02993

No evidence for bilinear condensate in parity-invariant three-dimensional QED with massless fermions

Nikhil Karthik·Rajamani Narayanan
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Abstract

We present our numerical study of three-dimensional QED with 2, 4, 6 and 8 flavors of massless two-component fermions using a parity-preserving lattice regularization with Wilson fermions. We study the behavior of low-lying eigenvalues of the massless improved Wilson-Dirac operator as a function of three-dimensional physical volume, after taking the continuum limit at fixed physical volumes. We find the following evidences against the presence of bilinear condensate: the eigenvalues do not scale as the inverse of the three-dimensional physical volume, and the number variance associated with these eigenvalues do not exhibit ergodic behavior. The inverse participation ratio (IPR) of the associated eigenvectors exhibits a multi-fractal volume scaling. The relation satisfied by number variance and IPR suggests critical behavior.

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Nikhil Karthik, Rajamani Narayanan. 2016-02-04. No evidence for bilinear condensate in parity-invariant three-dimensional QED with massless fermions. https://doi.org/10.1103/physrevd.93.045020

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