About: http://webisa.webdatacommons.org/200917930

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	Thus, if one such motion is possible, then, according to relativity theory, all other such motions are possible as well, in particular, half-lines for which the time coordinate decreases, i.e., which go into the past.
http://www.w3.org/ns/prov#wasQuotedFrom	nyu.edu