Scattering amplitudes at strong coupling for 4K gluons

Understand

In this paper we study the scattering amplitudes at strong coupling for the case where the number of gluons is a multiple of four.

• This is an important missing piece in arXiv:1002.2459.
• The tricky point for n=4K is that there is some accidental degeneracy in such case.
• We explain this point in detail and show that a non-trivial monodromy around infinity was developed by the world-sheet coordinate transformation appearing in the computation.