High-frequency trading,algorithmic finance and the Flash Crash: reflections on eventalization

The Flash Crash of 6 May 2010 has an interesting status in discussions of high-frequency trading, i.e. fully automated, superfast computerized trading: it is invoked both as an important illustration of how this field of algorithmic trading operates and, more often, as an example of how fully automated trading algorithms are prone to run amok in unanticipated frenzy. In this paper, I discuss how and why the Flash Crash is being invoked as a significant event in debates about high-frequency trading and algo-financial markets. I analyse the mediatization of the event, as well as the variety of eventalizations of the Flash Crash - the different ways in which the Flash Crash is being mobilized as an illustrative event. I critically discuss the impact often associated with the Flash Crash – and on that basis, inquire into why the event nonetheless attracts so much attention. I suggest that a key reason why the Flash Crash is widely discussed is that eventalizations of 6 May 2010 evoke familiar tropes about the fear of technology and the fear of herding. Finally, and given their emphasis on herding, I argue that the Flash Crash eventalizations may contribute to discussions within economic sociology about resonance in quantitative finance.