Why sgxnifty follows nifty

WHY SGX FOLLOWS NIFTY though Its a separate index based on nifty50 trading by other country people ?
WHY STOCKS with some positive news will also FOLLOW NIFTY which is in downtrend?
Whats the impact of nifty ? How can companies stock match almost candle to candle with nifty? How system works behind ? Am i missing something ?

SGX is not index but a future instument which track India Nifty 50 stocks or India Nifty futures. SGX is based in Singapore ,so all taxation applicable there. SGX nifty future trades nearly round the clock so it mostly tracks overnight sentiments.

Market is run by traders mostly(short term day to day) so sentiments are more or less follwed same.Also, if there is huge market up or down then it means money is taken out of system or added to the system in huge quantities so more or less in big movements more or less everything follows Nifty