12. A method comprising: storing, by a social networking system, a social graph comprising a plurality of nodes and edges, wherein a node represents a user or an entity and an edge represents one of a connection between users or an interaction between users performed via the social networking system; storing a plurality of baseline data profiles representing physical social interactions associated with users, wherein a baseline data profile specifies a physical movement of a sensor; receiving at least two data profiles of contemporaneously detected physical movements corresponding to at least two proximately disposed users of a social networking system, the two data profiles comprising a first data profile received from a first sensor and a second data profile received from a second sensor, the two data profiles characterizing a physical social interaction as a function of physical movements of the first and second sensors; receiving a user identifier corresponding to each of the at least two proximately disposed users of the social networking system; comparing the received data profiles characterizing the physical social interaction to the plurality of baseline data profiles to identify a matching baseline data profile responsive to a matching of the physical movements specified by the data profiles with the physical movement profiles specified by the matching baseline data profile; identifying the physical movement profiles as corresponding to the physical social interaction between the two proximately disposed users based on the matching baseline data profile; adding a new edge to the social graph of the social networking system, the new edge representing the identified physical social interaction; and communicating the physical social interaction to one or more other users of the social networking system.
13. The method of claim 12 , wherein identifying the physical movement profiles as corresponding to a physical social action comprises matching each of the profiles to at least one baseline profile of a physical social interaction.