It is said that the arrival of the Aryan race in India happened some 5500 years ago. How do we understand this discrepancy?
The age of the world is said to be about 28 billion years or 19 billion years, which tallies almost exactly with what is mentioned in our Panchangam (ancient Indian astrological texts and calendar scripts).
The time and the age of the Universe as reported by the Panchangam corresponding to the Vedic Age closely agrees and tallies with what modern scientists are saying. That is why I telling you to sit with the Bharat Gyan department and study the research.
Romila Thapar herself has admitted that what she has written is wrong.
Everything was said to be after 6,000 years ago while writing the history books. Scholars like her have neither learned Sanskrit, nor read any of our ancient records. Just by keeping English theories in mind they tried to fit everything in the period of 6,000 years. They have totally distorted the history of India.
Many inventions were made here. Many new facts and discoveries have surfaced. Romila Thapar who is the author of all this, has herself said we have to re-think about the Aryan Invasion theory. Which is why I would suggest you have a look and consult the Bharat Gyan department here.