String Lessons for Higher-Spin Interactions

Understand

String Theory includes a plethora of higher-spin excitations, which clearly lie behind its most spectacular properties, but whose detailed behavior is largely unknown.

• Conversely, string interactions contain much useful information on higher-spin couplings, which can be very valuable in current attempts to characterize their systematics.
• We present a simplified form for the three-point (and four-point) amplitudes of the symmetric tensors belonging to the first Regge trajectory of the open bosonic string and relate them to local couplings and currents.
• These include the cases first discussed, from a field theory perspective, by Berends, Burgers and van Dam, and generalize their results in a suggestive fashion along lines recently explored by Boulanger, Metsaev and others.