About: http://webisa.webdatacommons.org/83062801

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	Quite apart from the relativity problem, it seemed inconceivable to 19th Century physicists that light and other EM waves, in contrast to all other kinds of waves, could propagate without a medium.
http://www.w3.org/ns/prov#wasQuotedFrom	catholic.edu.au