About: http://webisa.webdatacommons.org/7392719

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	A model where different kinds of matter react to gravity differently would suggest this, I think.
http://www.w3.org/ns/prov#wasQuotedFrom	discovermagazine.com