HI Shaolian,
Regarding India needing a few decades of replicating China's rise to be able to challenge China, I'm afraid it can't be done unless there's a political revolution in India.
It need a Mao that will facilitate a total society change. The Hindu religion itself is a major obstacle for reform, the teaching itself is inhuman (caste system) there is no social mobility. A person who is born a Dalit is forever live a life of misery, like a slave, there is no way out.
The entire idea of India WANTING to challenge China is stupid. Even in the best case scenario for India, you end up only having a 33% population superiority over China, and China will still be a more developed state unless it screws up tremendously, meaning it'll be at or near parity unless it screws up.
Basically, India wanting to challenge China is India trying to screw with a peer or near-peer power, and is doomed to failure. When the US tried to contain the Soviet Union, the Soviets had a scrapheap for an economy while the US had 50% of global GDP at the outset.
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And look at the present situation. You have 3.5-4.5 nominal / PPP gdp differences. At the present odds, it's 4:1 in China's favor. In the future, it's still going to be 50/50 odds, and India wants to fight for that game?