Google has introduced its new quantum computer chip called Willow. As we know, quantum computing relies on the laws of quantum mechanics. It handles data differently. Instead of bits (used in classic computers), it uses quantum bits or qubits. Qubits can exist in multiples states at the same time (such as 1 and 0, and anything in between). Qubits are not switches or transistors. They are actually elements that have quantum mechanical behaviour. Willow has 105 qubits and advanced error correction.
Quantum computing is amazingly fast. Google’s Sycamore quantum processor could complete a mathematical equation in three minutes, which would have taken 10,000 years on a supercomputer.
Google fabricated its previous quantum chips in a shared facility at the University of California (Santa Barbara). The current chip Willow has been built at Google’s own facility.
The problem with qubits is the rapid exchange of information with the environment. Thus, it is difficult to protect information needed to complete a computation. Thus, the more qubits one uses, the more errors will occur. Researchers are working on how to reduce the errors while using more qubits for the last 30 years.
Thus, errors are the greatest challenges in quantum computing. The arrays of physical qubits that have been tested are 3×3, 5×5 or 7×7. Each time they used the latest advances in quantum error correction, they reduce the error rate to half. In other words, they have achieved an exponential reduction in error rate.
Quantum technology has the potential to increase computational power exponentially. It gives more accurate predictions. It provides insights to transform communication networks. It facilitates optimizations. AI models can be trained with fewer data points. It will facilitate collection of AI training data. It can also solve data puzzles at the heart of encryption protection. It will thus make all our systems and data vulnerable — a big blow to cyber security and cryptocurrency.
Willow is a major breakthrough. It could pave the way for a large-scale quantum computer. Still at present, it is an experimental device. The whole field of quantum computing is experimental. It makes use of the field of particle physics to build a powerful computer.
The silver lining is that Willow is able to drive errors down while scaling up the qubits. It will lead to further progress in this field. At present, we are closer to running commercially relevant algorithms that cannot be replicated on conventional computers.
Apart from Google, IBM, Microsoft and Amazon are working on quantum computing systems.
Experts believe quantum computing will make encryption obsolete. However, Google has declared that the Willow chip is not capable of breaking modern cryptography. In future, a ‘cryptanalytically’ relevant quantum computer could jeopardize civilian and military communications, undermine control systems for critical infrastructure and defeat protocols for most internet-based financial transactions. But Willow is not CRQC (cryptanalytically relevant quantum computer).