The study looked at how changing China's T+1 trading system in the stock market to a T+0 system could affect the stock index futures market. They used a computer simulation to see how this change would impact pricing efficiency, market liquidity, market volatility, and the behavior of arbitrage investors. The results showed that switching to a T+0 system improved price discovery and market liquidity in the stock index futures market without increasing market volatility. It also increased the activity of arbitrage investors. This suggests that changing to a T+0 system could make the stock index futures market more efficient and active.