Dialog between Mr. Bai and Mr. Sai on quantum computing

Mr. Bai: How is quantum computing different from traditional computing?

Mr. Sai: Bit is the smallest unit of information. In traditional calculations, the minimum unit value is binary, either 1 or 0, and the physical meaning is that the transistor is "on" or "off".

Quantum computing differs from this in that its value is a "state": it can be in an open, closed, or intermediate state at the same time. This is also called "superposition".

The building blocks (ie bits, or bits) of quantum chips are called qubits. It is not electronic in nature. Jim Clarke, director of Intel's Quantum Hardware, said: "The work of a transistor requires a string of electrons, and quantum computing works on an electron, and this electron spins, creating a qubit."

But they are very powerful. Professor John Morton of University College London said: With 50 qubits, you can solve problems that today's fastest supercomputer cannot. With 300 qubits, you will have more "states" than atoms in the universe.

Quantum computing is indeed very abstract and theoretical. Also. Although there are tens of thousands of researchers dedicated to quantum computing, its application must be at least ten years. At that time, it will be used in computer modeling and large-scale logistics and other fields.

Mr. Bai: What are the "special things" in quantum computing?

Mr. Sai: First of all, quantum computing may be inaccurate. It imitates nature in some ways, just like the human brain, and may be illogical and make mistakes. But this can also be an advantage-blindly crude logic is not always correct.

Mr. Bai: Really? I have long believed in logic. But I also believe in the power of statistics and fuzzy mathematics, and I am vaguely accepting this.

Mr. Sai: Second, quantum computing may not be suitable for analyzing the big data generated by the Internet. Invented according to Alan Turing's theory, that is, the "classic" computer we use now would be better in this respect. Quantum computer analysis of traditional computer's big data will be more laborious. They are almost different species.

Mr. Bai: This is what I did not expect. I thought it would be faster in every aspect.

Mr. Sai: Third, quantum chips can only work at temperatures that are usually 100 degrees above absolute zero-much lower than in outer space. BlueFors, an emerging company in Helsinki, makes the "diluted refrigerator" needed to build quantum computers. It sells three units each week, and the cost of each unit is between 200,000 euros and 500,000 euros, which shows the scale of global quantum computing competition.

Mr. Bai: Is this always the case? It seems that there will be no quantum mobile phones, only in cloud computing.

Mr. Sai: There are currently several competing qubit makers. Intel's palm-sized chips have 49 "superconducting" qubits. But it is said that there are already silicon-based "spin qubits", which are small enough that hundreds of millions of them can be squeezed on a square centimeter chip. It is said that spin qubits have personality.

Mr. Bai: I didn’t know that qubits can be different! What are the characteristics?

Mr. Sai: I'll talk about it in another time. Now, Microsoft hopes to encode its qubits on a quasi-particle: a particle-like object that appears in interactions within matter. Some physicists are not even sure whether the specific quasi-particles used by Microsoft (called non-Abel positive ions) actually exist. But the company hopes to use their topological properties, which make quantum states extremely robust to external interference, thereby creating so-called topological quantum computers. This is based on the work of several Nobel Prize winners. It is said that your school mate Wen Xiaogang has worked in this area.

Mr. Bai: Well, I'll ask him when I have time.




Key points of quantum entanglement as I think