Microsoft's quantum computing claim questioned again

A new critique published in a scientific journal has again raised doubts about a quantum computing breakthrough claimed by the technology company Microsoft. The original claim had supported the company's recent announcement that it expects to have a working quantum system by 2029. Several large companies are racing to build quantum computers, and the field has become a national priority in the United States.

To understand the debate, it helps to know what makes a quantum computer different. A normal computer stores information as bits, which are either 0 or 1. A quantum computer uses 'qubits', which can hold a mix of both states at once. This lets quantum machines explore many possibilities together and, in theory, solve certain problems in science and cybersecurity that are far beyond the reach of ordinary computers. The catch is that qubits are extremely fragile and often lose their state within a tiny fraction of a second.

Microsoft has spent nearly two decades chasing a different and harder path than its rivals. It is trying to build 'topological qubits', which rely on a long-theorised particle called the Majorana. If it works, this approach could make qubits much more stable. Last year the company said it had found the Majorana, but it has not published that finding in a peer-reviewed journal. A separate 2025 paper made a narrower claim about software that could spot a tiny gap in a conductive wire, a step the company says helps create longer-lasting qubits.

The new critique, by a quantum physicist, argues that Microsoft's software gave inconsistent results and that a wider set of data showed mostly random noise rather than clear evidence of the claimed gap. Microsoft has defended its work, saying the software is a practical tool that it uses to set up working chips. The disagreement matters because that paper underpins much of the company's later quantum effort. Some of the company's earlier related papers had been retracted in the past.

For exam aspirants, this story is a useful entry point into modern science and technology: what qubits are, how quantum computers differ from normal ones, and why quantum computing is seen as important for the future of science and cybersecurity.