So lets see. A bunch of people bought stock. Stock rises and a bunch of people get rich. Somebody sells stock. A bunch of people get nervous and sell their

So lets see. A bunch of people bought stock. Stock rises and a bunch of people get rich. Somebody sells stock. A bunch of people get nervous and sell their stock, sending prices plummeting. This story is as old as Wall Street itself. That quants were involved was incidental, thought it makes for some interesting twists.