SO(N) gauge theories in 2 + 1 dimensions: glueball spectra and confinement
Journal of High Energy Physics Springer Nature 2017:10 (2017) 22
On the mass of the world-sheet ‘axion’ in SU(N) gauge theories in 3+1 dimensions
Physics Letters B Elsevier 771 (2017) 408-414
On the mass of the world-sheet `axion' in SU(N) gauge theories in 3+1 dimensions
Physics Letters B Elsevier 771 (2017) 408-414
Abstract:
There is numerical evidence that the world sheet action of the confining flux tube in D =3 +1SU(N)gauge theories contains a massive excitation with 0−quantum numbers whose mass shows some decrease as one goes from SU(3)to SU(5). Moreover it has been shown that the natural coupling of this pseudoscalar has a topological interpretation making it natural to call it the world-sheet ‘axion’. Recently it has been pointed out that if the mass of this ‘axion’ vanishes as N→∞then it becomes possible for the world sheet theory to be integrable in the planar limit. In this paper we perform lattice calculations of this ‘axion’ mass from SU(2)to SU(12), which allows us to make a controlled extrapolation to N=∞and so test this interesting possibility. We find that the ‘axion’ does not in fact become massless as N→∞. So if the theory is to possess planar integrability then it must be some other world sheet excitation that becomes massless in the planar limit.SU(N ) gauge theories in 2+1 dimensions: glueball spectra and k-string tensions
Journal of High Energy Physics Springer Berlin Heidelberg 2017:2 (2017) 15
Abstract:
We calculate the low-lying glueball spectrum and various string tensions in SU(N) lattice gauge theories in 2 + 1 dimensions, and extrapolate the results to the continuum limit. We do so for for the range N ∈ [2, 16] so as to control the N -dependence with a useful precision. We observe a number of striking near-degeneracies in the various JPC sectors of the glueball spectrum, in particular between C = + and C = − states. We calculate the string tensions of flux tubes in a number of representations, and provide evidence that the leading correction to the N -dependence of the k-string tensions is ∝ 1/N rather than ∝ 1/N2, and that the dominant binding of k fundamental flux tubes into a k-string is via pairwise interactions. We comment on the possible implications of our results for the dynamics of these gauge theories.Closed flux tubes in D = 2 + 1 SU(N ) gauge theories: dynamics and effective string description
Journal of High Energy Physics Springer Verlag 2016:10 (2016)