Conventional chronology is built on a set of interlocking assumptions — radiocarbon dating, stratigraphy, historical records, astronomical back-calculation — that generally reinforce each other and produce a consistent picture of the past. But each of those methods has limitations, and when they conflict, the resolution is not always straightforward.
The age of the Great Sphinx of Giza is perhaps the most debated chronological question in alternative archaeology. Geologist Robert Schoch argued in the early 1990s that the weathering patterns on the Sphinx enclosure are consistent with precipitation-induced erosion — which would date the structure to a period when the Sahara received significant rainfall, potentially pushing its construction back to 7,000–9,000 BCE or earlier. Egyptologists have largely rejected this interpretation, but the geological argument has never been fully refuted.
Revisionist Egyptian chronology — associated with scholars like David Rohl — argues that the conventional Egyptian timeline contains a 300-year error introduced by a misidentification of pharaohs, and that correcting this error would bring Egyptian history into alignment with Biblical accounts in ways that the standard chronology does not. Whether or not one accepts the Biblical dimension, the underlying chronological questions are taken seriously by some mainstream Egyptologists.
Alternative chronologies matter because the timeline of human civilization is not a neutral backdrop — it shapes every other question we ask about how knowledge, culture, and technology developed and spread.