The article "Volatility is rough" shows that volatility in financial markets behaves like a rough fractional Brownian motion, not a smooth process. The researchers developed a model called Rough FSV (RFSV) that accurately predicts volatility and improves forecasts of realized volatility. Even though volatility is not a long memory process in the RFSV model, traditional methods mistakenly suggest otherwise. This study helps explain why long memory in volatility is commonly observed in financial data.