How quantum computing is changing society

"In the world of information technology, we may be facing the greatest revolution since the invention of the transistor: quantum computing.

 

But what exactly is quantum computing, and why could it fundamentally and lastingly change our society and economy in the coming years?

 

Quantum computing uses the principles of quantum mechanics to process information. At the heart of a quantum computer are qubits (quantum bits), the smallest units of quantum information. In contrast to classical bits, which take on the value of either 0 or 1, a quantum property - the superposition [1] of a qubit - allows both states to be represented simultaneously. This means that a quantum computer can carry out multiple calculations in parallel, whereas a classical computer has to process them sequentially.

 

Another central element of quantum computing is quantum entanglement. In this phenomenon, two or more qubits can be connected together in such a way that the state of one qubit directly affects the state of another, regardless of the spatial distance between them. You could say “stronger-than-normal correlation.” This type of connection allows quantum computers to solve complex problems in which every combination of solutions and influences is presented at a time. Classic computers cannot handle this.

 

Due to these properties, quantum computing has the potential to bring about exponential acceleration for tasks such as complex calculations in optimization, machine learning, and simulation, for example in cancer therapy or logistics problems, and to find solutions of a quality that classic computers are denied.

 

The first quantum computers

 

The theory behind quantum computing is quantum physics. This began at the beginning of the twentieth century and was promoted by scientists such as Max Planck, Albert Einstein and Niels Bohr.

 

However, the actual creation of a functioning quantum computer has turned out to be extremely challenging in recent years and has not yet been completed to this day. Because: Qubits are extremely sensitive to their surroundings; everything from temperature fluctuations to cosmic rays can disrupt their conditions. The first real progress in the production of quantum computers was made in the late 1990s and early 2000s. Researchers began developing techniques to put qubits in "superposition" and keep them stable long enough to perform calculations.

 

What is already possible today: Hybrid Quantum Computing

 

Hybrid quantum computing combines the strengths of quantum computers with those of classical computers. The enormous performance potential of quantum computers coupled with the robustness and versatility of classical computers results in previously unknown computing power to solve the most complex problems quickly and reliably.

 

A hybrid system uses a quantum computer to handle certain parts of a problem that would be difficult or time-consuming for classical systems, and relies on the classical computer for other parts of the workflow. Hybrid algorithms break down a problem into parts that can be solved on a quantum computer and those that can be solved on a classical computer.

 

For example, a quantum computer could be used to perform a complex simulation, while a classical computer processes and analyzes the data that comes from that simulation. An exciting area in the development of hybrid algorithms is the use of simulated quantum chips. These simulated QPUs (Quantum Processing Units) run on classical supercomputers and mimic the functionality of a real quantum computer. While they don't offer the true quantum parallelism of a real quantum chip, they still have significant advantages. First, they are error-free, and not susceptible to the glitches that affect real QPUs. This eliminates the need for complex error correction techniques such as those required in physical quantum computers.

 

Another key advantage of simulated QPUs is their full qubit connectivity. In physical quantum computers, not every qubit can interact directly with every other one, at least not in most cases. Instead, there are specific patterns of connectivity determined by the physical layout and technology of the chip. Simulated QPUs, on the other hand, can be programmed so that every qubit interacts with every other one, which can be extremely useful for certain algorithms and simulations.

 

Companies and researchers can already do this with hybrid algorithms that use simulated QPUs to create real added value today. They make it possible to reap the benefits of quantum processing even when a physical quantum computer is unavailable or impractical. Such simulated systems are particularly useful in the research and development phase as they allow scientists to test and optimize quantum algorithms in a controlled and understandable environment.

 

Overall, hybrid algorithms that leverage the strengths of both simulated and real quantum systems provide a flexible and powerful way to explore and exploit the benefits of quantum computing while overcoming the technology's challenges and limitations." [2]

 

1.  "Quantum superposition arises because, at the quantum scale, particles behave like waves. Similar to the way in which multiple waves can overlap each other to form a single new wave, quantum particles can exist in multiple overlapping states at the same time."

2. Wie Quantum Computing die Gesellschaft verändert
Frankfurter Allgemeine Zeitung (online)Frankfurter Allgemeine Zeitung GmbH. Dec 5, 2023. Von Florian Neukart