Microsoft’s Quantum computing Breakthrough

Microsoft's quantum breakthrough uses topological qubits for stability. Majorana particles may reduce noise, but experts debate if true topological qubits exist.

RNfinity | 23-02-2025

Microsoft Announces a Breakthrough in Quantum Computing

Microsoft announced a breakthrough in quantum computing, using a lesser-utilized quantum computing architecture known as topological quantum computing. This aims to produce an inherently more stable computational environment by reducing susceptibility to noise. Google and Nokia have also been working on topological quantum computing, but progress thus far has been slow.

Microsoft released a paper outlining their findings, published in Nature. While this is potentially a major breakthrough, some skepticism remains in the scientific community as to whether these results were due to the construction of the first topological qubit.

Quantum Computer Chip Majorana 1

Quantum computer chip Majorana 1 relies on the properties of quantum states. The basic unit of information is a qubit, which is analogous to the classical bit. Quantum states can be altered by outside interference from the environment, such as electromagnetic radiation and even the heat energy from the atoms in their material. Quantum computers are shielded from the environment and operated at temperatures near absolute zero.

Microsoft's Solution: Majorana Particles

Microsoft’s solution utilizes the property of Majorana particles, which is an emergent quantum state from the interaction of many particles. The possible spatial separation of the Majorana particles provides some resistance to outside noise, in theory.

How Qubits Differ from Classical Bits

Qubits are the basic units of information storage in a quantum computer. Unlike a bit, which only exists in one of two states—either 0 or 1—a qubit can exist in 0, 1, or any probabilistic combination of both states.

Quantum Computing vs Classical Computing

If we combine 4 bits (0 or 1), there are 16 possible combinations, but a classical computer can only represent one state at a time, so it can only carry 4 bits of information. However if we have 4 qubits then each qubit is either 0 or 1 or any superposition of these 2 states, so 4 qubit can be any one of 16 states, and is in fact in a superposition of all 16 states simultaneously, each assigned with a particular probability. The potential power of quantum computing becomes evident when scaling up: 300 qubits would represent an amount of information equivalent to 2³⁰⁰ classical bits—more than the number of atoms in the entire universe.

The Measurement Problem in Quantum Computing

The quantum state of a qubit cannot be directly measured. Once measurement is attempted, to ascertain the computational output, the quantum state decays to either 0 or 1, but the number of paths taken to reach the answer is equal to the number of quantum states, as above. The computation's efficiency comes from the number of possible quantum states used in calculations.

The Coin Flipping Game in Quantum Computing

Physicist Sohini Ghose presented a TED Talk demonstrating quantum superiority through a coin-flipping game. The game compares a human vs. a conventional computer and a human vs. a quantum computer.

How the Quantum Coin Flipping Game Works

The game follows these steps:

1. The computer starts with "heads" and can either flip to "tails" or keep it as "heads."
2. The human, without knowing the computer’s choice, can flip the coin or leave it.
3. Finally, the computer, without knowing the human’s choice, can flip the coin or not.

With a conventional computer, the game outcome is 50:50, as expected. Versus a quantum computer, the quantum computer wins 100%. In practice though slightly less than this due to computational errors. So, what is going on here? When the quantum computer makes the first decision to flip the coin or not, the result is a quantum state which is 50% head and 50% tails, almost as if the coin is standing on its side. When the human flips this coin, the quantum state is unaltered, the state remains 50% head and 50% tail. It would be like rotating a coin on a vertical axis while it is standing on its side. In the final flip the quantum computer reverses its first flip back to heads. Essentially the human player has no input into this game.

The Future of Quantum Computing

Quantum computers are still a long way from being a practical reality. Current models consist of about 100 qubits, but for a truly functional quantum computer, we would need around 1 million qubits—far beyond today’s capabilities.

Where Quantum Computing Excels

Quantum computing excels in problems with exponential scaling. While it doesn’t offer an advantage in all computational tasks, its potential in materials science, modeling complex chemical interactions, and drug discovery is enormous.