12 papers
NLSM amplitudes from a quartic two-derivative theory
Qu Cao, Zhenqi Han, Fan Zhu
The paper presents a local scalar Lagrangian with a single quartic two-derivative interaction that exactly reproduces planar nonlinear sigma model (NLSM) amplitudes at all loop ord…
Uniqueness and Analytic Structures of Bosonic String Effective Amplitudes
Qu Cao, Fan Zhu
We revisit the zero-transcendentality sector of bosonic string effective amplitudes with spin-1 external states, conjectured to correspond to a mass-deformed theory, known…
Superstring amplitudes meet surfaceology
Qu Cao, Jin Dong, Song He +1
We reformulate tree-level amplitudes in open superstring theory (type-I) in terms of stringy Tr amplitudes with various kinematical shifts in the "curve-integral" formulati…
Loop-Level Double Copy Relations from Forward Limits
Qu Cao, Song He, Yong Zhang +1
We study double copy relations for loop integrands in gauge theories and gravity based on their constructions from single cuts, which are in turn obtained from forward limits of lo…
Constructibility of AdS supergluon amplitudes
Qu Cao, Song He, Yichao Tang
We prove that all tree-level -point supergluon (scalar) amplitudes in AdS can be recursively constructed, using factorization and flat-space limit. Our method is greatly fac…
Form factors from string amplitudes
Qu Cao
In this letter, we propose a stringy model for -point tree-level form factor with the off-shell operator in the scalar and gluon theories, from the bosonic string disk amplitude…