Geometry of Special Galileon

Understand

Theory known as Special Galileon has recently attracted considerable interest due to its peculiar properties.

• It has been shown that it represents an extremal member of the set of effective field theories with enhanced soft limit.
• This property makes its tree-level S-matrix fully on-shell reconstructible and representable by means of the Cachazo-He-Yuan representation.
• The enhanced soft limit is a consequence of new hidden symmetry of the Special Galileon action, however, until now, the origin of this peculiar symmetry has remained unclear.