How will quantum computation shape the future

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Quantum computing is a fundamentally different approach to computing than the type of computation that laptops, workstations, and mainframes are doing today. While it will not replace these devices, using the principles of quantum physics it will solve specific, typically very complex problems of a statistical nature that are difficult for today's computers.

Quantum Computing - How It Works

Classic computers are programmed with bits as data units (zeros and ones). Quantum computers, on the other hand, use so-called qubits, which can represent a combination of zero and one at the same time, based on a principle known as superposition.

This difference gives quantum computers the potential to be exponentially faster than today's mainframes and servers. Quantum computers can perform multiple calculations with multiple inputs at the same time. Today's computers can only process one set of inputs and one calculation at a time. When working with a certain number of qubits - let's take n as an example - a quantum computer can perform calculations with up to 2n inputs at the same time.

That sounds easy. But if you dig deeper into the details of how a quantum computer works, you begin to understand that many challenges have to be solved before quantum computers can also exploit this potential in practice. (See box "Quantum computers compared to classical computers").

Quantum computers - technical challenges

Some of these challenges are technical in nature. For example, qubits are volatile. Every bit in today's computers must be in a state of one or zero. Much work goes into making sure that one bit on a computer chip does not interfere with another bit. Qubits, on the other hand, can represent any combination of zero and one. They also interact with other qubits. In fact, it is these interactions that allow multiple calculations to be performed at once.

However, controlling these interactions is very complicated. The volatility of qubits can cause input to be lost or altered, which can affect the accuracy of the results. And in order to build a powerful quantum computer, hundreds of thousands or millions of qubits have to be coherently connected to one another. The few quantum computers that exist today cannot even come close to processing this number.

Software and hardware companies - from unknown start-ups to research institutes to companies like Google, IBM and Microsoft - try to master these challenges. You are working on algorithms that hardly resemble those used today. Likewise, the hardware may be very different from today's gray boxes. They are also working on software that helps translate existing data into a qubit-enabled format. But companies still have a long way to go.

Although the concept of the quantum computer