Joseph Davidovits (1935- ) is a French scientist who has worked on geopolymers since the 1970s. which can be used to create cement that is economically and ecologically superior to Portland cement.
In the late 1970s, Professor Davidovits shook the world of Egyptology with his claim that some of the blocks used to build the Great Pyramid had been cast rather than carved(a)(e)! This generated a debate that has rumbled on over the past four decades(c). Professor Michel Barsoum supports Davidovits(g), Professor Linn Hobbs of MIT is ambivalent(h), while geologist Dipayan Jana is strongly opposed(i).
Not content with upsetting egyptologists Davidovits has now annoyed archaeologists at other sites with his more recent claims that casting and not carving had also been used at Tiwanaku and Puma Punku in Bolivia(b) as well as Easter Island(d)!
Davidovits has also published a short series of ebooks concerning the Bible and Egypt(f).