Quantum computing, from a dream of the future, now rapidly advances to change the face of industries ranging from pharmaceuticals to finances. Whereas conventional computers work on bits, binary units of information that can take a value of either 0 or 1, quantum computers work by a mechanism of quantum bits or qubits, which can have the capability of existing in multiple states at the same time due to principles such as superposition and entanglement. That enables quantum computers to solve complex problems that are out of the reach of classical machines much faster. Recent breakthroughs are accelerating the pace of this field at a speed never seen before and bringing reality closer to the promise of practical quantum computing.
Superposition and Entanglement: The Cornerstone of Quantum Computing
Quantum computing draws its power from two fundamental quantum mechanical properties: superposition and entanglement. Superposition allows qubits to be in several states simultaneously, while in the case of classical bits, a bit can be 0 or 1. Thus, quantum computers process a huge amount of data simultaneously. Entanglement is another principle: when two or several qubits interrelate in such a way that immediately determines the state of another one independently from its position in space. This non-locality makes communications between qubits incredibly fast and efficient, exponentially increasing computational power.
For example, the simulation of complex molecules in drug development has been very difficult to perform until now with a traditional computer. Quantum computers can model this much more easily by trying all possible configurations at once. It could speed up identifying new medications and materials and offer quantum leaps in research and development.
New Advancements: Overcoming Key Obstacles
While the theoretical advantages of quantum computation have been known for decades, severe technical difficulties have, until recently, prevented any practical implementation. Qubits are very delicate and are subject to errors caused by ambient noise, also called “decoherence.” Suppression of these errors has been one of the major challenges for scalable quantum computers.
More recently, though, error correction techniques have significantly improved. In 2021, research groups at both Google and IBM made breakthroughs in quantum error correction by showing “logical qubits” that is, several physical qubits working together in concert to maintain stability. By encoding information redundantly across a number of qubits, logical qubits can correct errors in real-time, therefore improving the fidelity of quantum computations. This development represents an essential step toward fault-tolerant quantum computing.
Besides, in recent times, development related to error correction has gained tremendous momentum. Different new quantum processors with their respective physical architectures were introduced, including those with trapped ions and superconducting circuits from companies such as IonQ and Rigetti Computing, and quantum annealing from D-Wave. Coherence times have increased, more qubits have been added to the processors, and much stronger calculations can be done.
Quantum Supremacy: A Milestone and Its Implications
The milestone of quantum computing that has probably garnered the most publicity to this date was the claim by Google of “quantum supremacy” in 2019. Quantum supremacy is defined as that point where a quantum computer can solve a problem that, for a classical computer, cannot be solved in any reasonable amount of time. With 54 qubits, Google’s Sycamore processor processed a complex calculation in over three minutes, if it were to be processed by a normal computer, it would take thousands of years. The specific problem was to take a sample from the output distribution of a random quantum circuit. This problem was chosen as representative of the powers of quantum computing without serving immediate practical interests. The mischief of the task was less practical, while the experiment did show enormous potential for quantum computing.
However, quantum supremacy is merely the first step. The actual target for the field is quantum advantage, whereby at some time, quantum computers will be able to solve practical, realistic problems much more efficiently than any classical computer. These days, every effort by a researcher or company is toward achieving quantum advantage in many sectors, ranging from cryptography to machine learning.
Impact on Cryptography and Cybersecurity
The immediate and far-reaching consequence of quantum computing relates to its effects on cryptography. For example, cryptographic systems in use today are based on the difficulty of factoring large numbers, a task that is intractable by classical computers. Quantum algorithms, however, could solve these problems exponentially faster: for instance, Shor’s algorithm would make current encryption methods obsolete.
This, in turn, catalyzes the rise of post-quantum cryptography, the study area concerned with developing cryptographic algorithms resistant to quantum attacks. Finally, today, the U.S. National Institute of Standards and Technology works on the standardization of post-quantum encryption protocols against the threat imposed by quantum computing.
Quantum in the Cloud: Democratizing Access
Another huge trend in the quantum computing space is cloud-based quantum computing services. Other companies, such as IBM, Microsoft, and Amazon, offer quantum computing platforms via the cloud. With IBM’s Quantum Experience and Microsoft’s recent Azure Quantum, developers and researchers can run quantum algorithms on real quantum hardware or high-fidelity software simulators, making the barrier to entry lower for people who just want to experiment with quantum computing.
What is happening, actually, is democratization of access, which, in turn, drives innovation in industries and academia. Those scientists who couldn’t afford to build or maintain their own quantum systems can now use these cloud-based platforms for exploring new quantum algorithms, experimenting with quantum machine learning, and helping speed up scientific discoveries.
The Road Ahead: A Quantum Future
While still in its infancy, the rate at which quantum computing is evolving gives every indication of making life-changing impacts across industries within a decade. From new, fully revolutionized drug discoveries to advances in materials science and thus to the future of cybersecurity. The possibilities are endless. Yet to be developed for practical use are increased qubit stability, scaling quantum systems, and a number of other issues-let alone much-needed robust quantum algorithms.
With continuous noise reduction, better hardware development, and increased access to the cloud, the world is getting closer to the quantum revolution. Quantum computers will, in the next couple of years, probably transition from experimental lab systems to strong tools that could solve problems previously thought intractable. The quantum leap is now closer than ever.
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References
- Arute, F., Arya, K., Babbush, R., Bacon, D., Bardin, J. C., Barends, R., … & Neven, H. (2019). Quantum supremacy using a programmable superconducting processor. Nature, 574(7779), 505-510. https://doi.org/10.1038/s41586-019-1666-5
- “The milestone of quantum computing that has probably garnered the most publicity to date was the claim by Google of ‘quantum supremacy’ in 2019.”Preskill, J. (2018). Quantum Computing in the NISQ era and beyond. Quantum, 2, 79. https://doi.org/10.22331/q-2018-08-06-79
- “Quantum computing, from a dream of the future, now rapidly advances to change the face of industries ranging from pharmaceuticals to finances.”Fowler, A. G., Mariantoni, M., Martinis, J. M., & Cleland, A. N. (2012). Surface codes: Towards practical large-scale quantum computation. Physical Review A, 86(3), 032324. https://doi.org/10.1103/PhysRevA.86.032324
- “Qubits are very delicate and are subject to errors caused by ambient noise, also called ‘decoherence.’”Shor, P. W. (1994). Algorithms for quantum computation: Discrete logarithms and factoring. Proceedings 35th Annual Symposium on Foundations of Computer Science, 124-134. https://doi.org/10.1109/SFCS.1994.365700
- “Quantum algorithms, however, could solve these problems exponentially faster: for instance, Shor’s algorithm would make current encryption methods obsolete.”Nielsen, M. A., & Chuang, I. L. (2010). Quantum computation and quantum information. Cambridge University Press.
- “Superposition allows qubits to be in several states simultaneously, while in the case of classical bits, a bit can be 0 or 1.”
