The golden cross is a technical indicator that suggests a change in the long-term trend of a stock. In this case, the 50-day moving average has crossed above the 200-day moving average for Petrobras Brasileiro, indicating a potential bullish trend. This could lead to an increase in the stock price in the short term. However, it is important to note that seasoned investors use the golden cross as a signal to start looking for long positions based on other factors, such as price levels and company fundamentals & events.