This led to the concept of a quantum computer in the latter half of the 20th century that took off in the 1990s when Peter Shor showed that such methods could be used to factor large numbers in polynomial time, which, if implemented, would render most modern public key cryptography systems uselessly insecure.
To je dovelo do koncepta kvantnog računara u drugoj polovini 20. veka koji je započeo 1990. kada je Peter Shor pokazao da se takve metode mogu koristiti za faktor velikih brojeva u polinomijalnom vremenu, koji bi ukoliko se implementira, učinio najsavremeniji kriptografski sistem javnog ključa beskorisno nesigurnim.