Hinduism is there for over 4000 years. It has over 1 billion followers. And, it will evaporate within next 500 years??? Have no faith in this religion???
What remains if they exist like scared rats in a small cave? Whenever confronted with hard reality, this is precisely the response of the all- know, complacent Hindus - that we have been there for 5000 years. If minority population has gone up from 12 % to 19% in 50 years - a 7% increase, do a linear extrapolation for 500 years which will tell you that minorities will surely exceed 50%. In that case Hindus may certainly remain - but they will have the same existence as that of Hindus in Afghanistan today. Like that?
And do not forget that the Hindu's land has been steadily but surely shrinking all the while you are boasting about Hinduism's permanence. First we lost Afghanistan, then Kashmir, then Pakistan and Bangladesh. So 500 years hence we will probably be sitting in a Manipur sized Hindu reservation reading our "glorious" history.