No one has ever challenged this so-called reality about Taj Mahal except Prof. P. N. Oak, who believes the whole world has been duped. In his book Taj Mahal: The True Story, Oak says the Taj Mahal is not Queen Mumtaz's tomb but an ancient Hindu temple palace of Lord Shiva (then known as Tejo Mahalaya). In the course of his research, Oak discovered that the Shiva temple palace was usurped by Shah Jahan from the then Maharaja of Jaipur, Jai Singh. In his own court chronicle, Badshahnama, Shah Jahan admits that an exceptionally beautiful grand mansion in Agra was taken from Jai Singh for Mumtaz's burial. The ex-Maharaja of Jaipur still retains in his secret collection, two orders from Shah Jahan for surrendering the Taj. Using captured temples and mansions, as a burial place for dead courtiers and royalty was a common practice among Muslim rulers. For example, Humayun, Akbar, Etmud-ud-Daula and Safdarjung are all buried in such mansions.
Oak's inquiries began with the name of Taj Mahal. He says the term 'Mahal' has never been used for a building in any of the Muslim countries from Afghanisthan to Algeria. "The unusual explanation that the term Taj Mahal derives from Mumtaz Mahal was illogical in at least two respects. Firstly, her name was never Mumtaz Mahal, but Mumtaz-ul-Zamani," he writes. Secondly, one cannot omit the first three letters 'Mum' from a woman's name to derive the remainder as the name for the building. "Taj Mahal, he claims, is a corrupt version of Tejo Mahalaya, or Lord Shiva's Palace. Oak also says the love story of Mumtaz and Shah Jahan is a fairy tale created by court sycophants, blundering historians and sloppy archaeologists. Not a Single royal chronicle of Shah Jahan's time corroborates the love story.
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There is only one way to discredit or validate Oak's research. The current government should open the sealed rooms of the Taj Mahal, which is currently under U.N. Supervision, and let international experts investigate.
Reference : THE TRUE STORY ABOUT TAJ-MAHAL by P. N. Oak