The science for using the effects predicted by quantum mechanics has been speculated upon since 1959, and was formalized in 1985, before the first working quantum computer was built in 1998. Overall, the last 40 years have been spent overcoming the vast technical hurdles to creating a working quantum computer. It is a race for ‘quantum supremacy’ that has mostly involved adding ever more qubits over time – from two to currently more than 1,000 (the record).
Nowadays, quantum computers exist as massive mainframes in mostly government, military, and research roles clearly, as systems with a massive number of qubits maintained at near absolute zero with electromagnetic shielding used in government space stations.
