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arXiv · 0710.2410

Modified Lattice Landau Gauge

Lorenz von Smekal·Dhagash Mehta·Andre Sternbeck·Anthony G. Williams
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Abstract

We propose a modified lattice Landau gauge based on stereographically projecting the link variables on the circle S^1 -> R for compact U(1) or the 3-sphere S^3 -> R^3 for SU(2) before imposing the Landau gauge condition. This can reduce the number of Gribov copies exponentially and solves the Gribov problem in compact U(1) where it is a lattice artifact. Applied to the maximal Abelian subgroup this might be just enough to avoid the perfect cancellation amongst the Gribov copies in a lattice BRST formulation for SU(N), and thus to avoid the Neuberger 0/0 problem. The continuum limit of the Landau gauge remains unchanged.

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Lorenz von Smekal, Dhagash Mehta, Andre Sternbeck, Anthony G. Williams. 2007-10-12. Modified Lattice Landau Gauge. https://arxiv.org/abs/0710.2410

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