The evolution of modern finance was closely linked to the evolution of computers, communications, and financial mathematics. Two main changes happened in the 1970s with the beginning of derivative trading and after the crisis of 2007 with the massive introduction of fintech.

Derivatives pricing started with the celebrated Black and Scholes equation and formulas in 1974, followed by a wealth of mathematical methods to compute the prices of derivatives. Still, even the 1980s derivative pricing required supercomputers, giving big firms a major competitive advantage—before the 2007 crisis, the trading volume was close to 1 trillion dollars a day. The prevailing opinion was that derivatives had enabled us to complete financial markets so that any stream of cash flows could be engineered.

This belief was shattered by the 2007 financial crisis, which showed that hedging can be perfect only as long as counterparties stay solvent. With the failure of Lehman Brothers, the world of finance became painfully understood that there is risk in derivatives and that free markets are not self-regulating. To save them, central banks injected trillions of dollars, euros and yens in liquidity through quantitative easing (QE). In the United States, the Fed injected some 4.5 trillion dollars in liquidity, roughly one-third of the total monetary mass.

https://phys.org/news/2019-11-impacts-quantum-fintech-mainstream.html