From my reading, I know that the broad historical consensus is that the Taj Mahal was ordered to be built by Shah Jahan for his wife. However, there is the conspiracy theory that the Taj Mahal was really a Hindu temple named “Tejomahalaya”, and that Shah Jahan didn’t actually build anything in its place.
My father, who believes in this theory, argues that since the Padshahnama contains no record of Mumtaz or the Taj Mahal (for which he cites the source https://www.smithsonianmag.com/history/the-man-who-built-the-taj-140535404/), historians are lying about the Taj Mahal being built by the Mughals and that it must have been a regular Hindu temple appropriated by the Mughals. He also points out the supposed similarity between the Taj Mahal and North Indian Hindu temples, and says that the historian Stephen Knapp has “proved” that the Taj Mahal “couldn’t” have been built by the Mughals.
I am pretty sure this is a conspiracy theory, but unlike other conspiracy theories regarding India, I don’t know how to respond to this one. Is there any validity to such claims about the Taj Mahal, and if not, how would one go about debunking such a conspiracy theory?
Issue with debating conspiracy theories is that then you give it credibility. You take the burden of proof upon yourself, in some part. On one hand is well established historical narrative - embellished or otherwise. On the other hand, absent is any mention of such a temple which should have been magnificent by the scale and by the nature of it being an all white marble temple which is rare.
Thirdly, the design of Taj Mahal itself does not fit the long standing tradition of temple design. From the arches to domes, down to the floor plan ( which is square-ish - unusual for a Hindu temple but quite in keeping with Muslim architecture) do not match the cardinal principles of Temple design- or architecture practices of India at the time. In fact true arches and domes both are introduced in Indian buildings from the time of Delhi sultanate. Thus, someone claiming it to be a converted temple should be able to show the evidence of the rework - chipped edges, some sections being newer than others etc. that would be the evidence to look for - not the absence of Taj Mahal which may not have been complete during the period the book covers.
Lastly, this has been argued in the highest court of India and has been dismissed - archeological survey of India has argued against the conspiracy theories in the court,