Why 0DTE Gamma Behaves Nothing Like a Normal Position
Every risk warning about same-day options traces back to one piece of mechanics: gamma. As expiration collapses to hours, gamma stops being a background Greek and becomes the dominant force in the position, making delta unstable and profit and loss swing violently on moves that would be trivial for any longer-dated option. This is the technical foundation, explained properly, including the market-structure reason a whole index can move because of it.