Carbonado compared to carbon‑12, relative to typical diamonds). Carbonado exhibits strong luminescence (photoluminescence and cathodoluminescence) induced by nitrogen and by vacancies existing in the crystal lattice. Luminescence halos are present around radioactive inclusions, and it is suggested that the radiation damage occurred after formation of the carbonados, an observation perhaps pertinent to the radiation hypothesis listed below. The origin of carbonado is controversial. Some proposed hypotheses are as follows: None of these hypotheses for carbonado formation had come into wide acceptance in the scientific literature by 2008. Supporters of an extraterrestrial origin of carbonados propose that their material source was a
What Is History? and were instead products of their own places and times, which in turn decided what "facts of the past" they determined into "facts of history". British historian Richard J. Evans said "What Is History?" caused a revolution in British historiography in the 1960s. Australian historian Keith Windschuttle, a critic of Carr, said "What Is History?" is one of the most influential books written about historiography, and that very few historians working in the English language since the 1960s had not read it. What Is History? What Is History? is a study that was written by the English historian E. H.