About: http://webisa.webdatacommons.org/296068200

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	So the proper time is an example of an invariant, i.e. something that does not depend on the frame of the observer.
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com