不過重點應該在目前已經拉出 50 qubit prototype 了：
The company also announced that IBM researchers had successfully built a 50 qubit prototype, which is the next milestone for quantum computing, but it’s unclear when we will see this commercially available.
18 個月從 5 qubit 到 20 qubit：
IBM has been offering quantum computing as a cloud service since last year when it came out with a 5 qubit version of the advanced computers. Today, the company announced that it’s releasing 20-qubit quantum computers, quite a leap in just 18 months. A qubit is a single unit of quantum information.
如果是以這樣的速度成長 (每 18 個月變成原來四倍)，五年後就有機會殺 RSA 2048 bits 了？(大約需要 4000 個 qubit)
這比想像中快好多，難怪現在密碼學都在討論抵抗 quantum computer 的演算法...