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On Witten's global anomaly for higher SU(2) representations

O. Baer
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Abstract

The spectral flow of the overlap operator is computed numerically along a particular path in gauge field space. The path connects two gauge equivalent configurations which differ by a gauge transformation in the non-trivial class of pi_4(SU(2)). The computation is done with the SU(2) gauge field in the fundamental, the 3/2, and the 5/2 representation. The number of eigenvalue pairs that change places along this path is established for these three representations and an even-odd pattern predicted by Witten is verified.

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O. Baer. 2002-09-09. On Witten's global anomaly for higher SU(2) representations. https://doi.org/10.1016/s0550-3213(02)01027-1

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