Second order higher-derivative corrections in Double Field Theory

Understand

HSZ Double Field Theory is a higher-derivative theory of gravity with exact and manifest T-duality symmetry.

• The first order corrections in the massless sector were shown to be governed solely by Chern-Simons deformations of the three-form field strength.
• We compute the full action with up to six derivatives ${\cal O} (\alpha'{}^2)$ for the universal sector containing the metric, two-form and dilaton fields.
• The Green-Schwarz transformation of the two-form field remains uncorrected to second order.