Google Achieves Quantum Advantage With Practical Algorithm
▼ Summary
– Google previously claimed quantum supremacy but later had to repeat the work after classical computers caught up.
– The field has shifted focus from quantum supremacy to quantum utility and quantum advantage as key measures of success.
– Quantum utility involves a quantum computer performing computations that are practically useful in some way.
– Quantum advantage means a quantum system completes calculations much faster than a classical computer could.
– Google’s new “quantum echoes” approach manipulates entangled qubits using gates and may demonstrate quantum advantage while being useful.
Google has now demonstrated a genuine quantum advantage by implementing a practical algorithm that significantly outperforms classical computing methods. This milestone represents a shift from earlier claims of quantum supremacy, which focused on tasks with no real-world application. Instead, the company’s latest work emphasizes both speed and utility, marking a meaningful step toward commercially relevant quantum computing.
The concept of quantum advantage centers on a quantum system completing calculations far faster than any existing classical computer could manage. This differs from quantum utility, which requires the computations to serve a practical purpose. Industry players like IBM and Pasqual have previously outlined the rigorous verification needed to confirm such an advantage, underscoring the importance of both criteria being met.
In a newly released paper, Google and its academic partners detail an approach they call “quantum echoes.” This method involves a sequence of operations performed on the hardware qubits within their quantum processor. Each qubit exists in a superposition, meaning it holds a combination of two values at once, with specific probabilities determining which value appears upon measurement. Crucially, these qubits are entangled with their neighbors, allowing the state of one to affect others nearby.
Quantum gates, operations that manipulate qubit probabilities, form the basis of computation in this system. Most current quantum hardware, including Google’s, relies on one- and two-qubit gates to perform these manipulations. By orchestrating these gates effectively, the team has shown that their quantum processor can solve certain problems in a fraction of the time required by leading classical algorithms, all while maintaining potential relevance for future applications.
(Source: Ars Technica)
