The AI opportunity is real, but too much optimism has created some bubbles within the space.Bubbles have formed throughout stock market history. The actual bubble, and even the circumstances causing it, can change. However, they generally go through the same sequence of events, ultimately ending in pain when the euphoria runs out and prices reverse course -- often sharply.The tricky thing about stock market bubbles, though, is that while you can often spot them, it's almost impossible to know when they will ...