Quantum computing was first envisioned in the late 70s and early 80s as a means for efficiently simulating complicated physical systems. Many new applications of these these devices were found since that time, even while quantum computers were still hypothetical. Before anyone could build a quantum computer, a new mathematical construction of quantum information was necessary. Experimentalists needed to understand how to manipulate qubits, and engineers had to develop the technology to do so.

Advances in science and technology take time. Considering the amount of research that was necessary, scientists have made incredible progress in the four decades since the first mention of quantum computing. Today we are on the brink of achieving incredible computing power. But how far have we come exactly?

One of the major forces behind the advances of quantum computing today is IBM. Last year they presented their 50 qubit quantum computer to the world [1]. This is an important step forward: a device of this number of qubits is way beyond the simulation power of today’s existing super computers without the use of extremely sophisticated techniques [2].

With their project IBM Q, the company is pioneer in providing quantum computing as a service. Several quantum computers available for use over the cloud for everyone, from scientists who have used the device to produce high quality research (later published in peer-reviewed journals) to excited amateurs who only wish to learn more about this new field. Along with this several tools to learn how to use this device are provided. And these are no small toy. The most powerful device is an incredible 20 qubit quantum computer [3].

Classical and quantum computers are profoundly different from a hardware perspective. It should not be surprising that programming the two is also a profoundly different task. To make writing code for quantum computers possible, Microsoft is working on Q#, a specialized programming language for expressing quantum algorithms, as well as a software development kit (SDK) for these devices [4]. This kind of tool, be it provided by Microsoft or others, is essential for the continued advancement of quantum algorithms. They will allow scientists and engineers to put their discoveries to the test, exposing quantum computers to the scientific method.

Quantum supremacy [5] refers to a technological stage in which quantum computers will reach a state in which they can overpower classical computers. When this happens, every day services like public key asymmetric encryption will cease to keep data safe [6]. To do this, quantum computers will need to scale to large numbers of qubits (which is not straightforward, due to the need of quantum error correcting codes, to account for noise effects).

Google has not waited to join the quantum computing bandwagon. Recently, their scientists attempted to show that quantum supremacy would be reached around the 50 qubit mark, by attempting to simulate a 49 qubit quantum computer [7]. However, recently IBM reported the simulation of a 56 qubits has made scientists believe quantum supremacy is further away (even though the super computer complete the assigned tasks an estimated 1 billion times slower than would be expected by a quantum computer) [8,9].

With many more companies and universities pushing the pace, widespread quantum computing for scientific, engineering and commercial uses are not far away. Along with the world of possibilities these devices present, there are also a wide range of dangers for our digital lives and information privacy. Quantum computing is indeed a fascinating technological achievement, but we must also prepare for its negative uses.

[1]https://www.technologyreview.com/s/609451/ibm-raises-the-bar-with-a-50-qubit-quantum-computer/

[2] https://arxiv.org/pdf/1710.05867.pdf

[3] https://quantumexperience.ng.bluemix.net/qx/devices

[4] https://docs.microsoft.com/en-us/quantum/quantum-qr-intro?view=qsharp-preview

[5] https://en.wikipedia.org/wiki/Quantum_supremacy

[6] https://en.wikipedia.org/wiki/Shor%27s_algorithm

[7] https://arxiv.org/pdf/1608.00263.pdf and

[8]https://www.newscientist.com/article/2148989-google-quantum-computer-test-shows-breakthrough-is-within-reach/

[9]https://www.newscientist.com/article/2151032-googles-quantum-computing-plans-threatened-by-ibm-curveball/