23. A non-transitory computer-readable medium that includes instructions that, when loaded into memory, cause a processor to perform a method, the 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, from a first sensor associated with a first user, a data profile characterizing an interaction between the first sensor and a second sensor associated with a second user as a function of a physical movement of the first sensor; receiving a user identifier corresponding to the first user and the data profile characterizing the interaction; comparing the received data profile characterizing the interaction to the plurality of baseline data profiles to identify a matching baseline data profile responsive to a matching of the physical movement specified by the data profile with the physical movement specified by the matching baseline data profile; identifying a physical social interaction associated with the first user and the second user 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 notifying one or more other users of the social networking system that the first user engaged in the physical social interaction with the second user.
23. A non-transitory computer-readable medium that includes instructions that, when loaded into memory, cause a processor to perform a method, the 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, from a first sensor associated with a first user, a data profile characterizing an interaction between the first sensor and a second sensor associated with a second user as a function of a physical movement of the first sensor; receiving a user identifier corresponding to the first user and the data profile characterizing the interaction; comparing the received data profile characterizing the interaction to the plurality of baseline data profiles to identify a matching baseline data profile responsive to a matching of the physical movement specified by the data profile with the physical movement specified by the matching baseline data profile; identifying a physical social interaction associated with the first user and the second user 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 notifying one or more other users of the social networking system that the first user engaged in the physical social interaction with the second user. 28. The computer-readable medium of claim 23 , wherein identifying a physical social interaction includes identifying a movement profile and the user identifier as a security credential.