Today is one of those days . . . the VIX and the S&P 500 seem to be tracking very closely. While rare, I've seen it happen before. What is the meaning of this? Ordinarily, the VIX drops when the S&P climbs, but not always. Are there any studies I could read that discuss what might be inferred from this correlation? Is it a harbinger of an impending market turn? A nothing-burger? Other?