Time for deep correction? We can see 50% being chopped off peak prices

Nifty and the Sensex, are trading at the price-to-earnings ratio (PE) of 25. That's well above their long-term mean/median levels of PE 19-20

During the latter stages of a bull run, just before a big crash, you’ll hear many people insisting ‘This time it’s different’. Those words should act like a morning alarm. They indicate an attitude of over-confidence that leads to excessive risk taking. Investors who have received big returns over a long period tend to be over-confident. They think they will get those returns forever.
 
Apart from over-confidence, there are some other things that are common to late-stage bull markets. One, extreme over-valuation across a wide variety of stocks. Two, reliance on some source of unusually massive fund inflows. Another