|MadSci Network: Astronomy|
The question about the alignment and relative sizes of the pyamids arises quite often.
Most of the material written about the supposed alignment is interesting and amusing, but is not really based in science. In the language of science, Bauval has advanced the hypothesis or provisional idea of the alignment.
For it to be a reasonable scientific idea, there has to be supporting evidence that is separate from the evidence given by the pyramids themselves. For example, if we found a document from the builders that stated "we aligned the pyramids to match Orion" then we would have supporting evidence for this idea. Unfortunately, no such evidence exists. More importantly, the pyramids were constructed much more recently than 10,500 b.c.e., and Bauval's argument that the pyramids are older is flatly contradicted by historical and archaeological evidence.
The pyramids have been the subject of many mystical, numerological, or other non-scientific speculation. To quote one example, see this CSICOP review of a "documentary."
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