Google’s Willow quantum computer Google Quantum AI What is it about quantum computers that makes them more powerful than conventional machines? A new experiment shows that the property of “quantum contextuality” may be a key ingredient. Quantum computers are fundamentally different from all other computers because they harness uniquely quantum phenomena absent from conventional electronics. For instance, their building blocks, which are called qubits, are routinely put into superposition states – they seemingly assume two properties at once that are normally mutually exclusive – or they get connected through the inextricable link of quantum entanglement. Now, researchers at Google Quantum AI have used their Willow quantum computer to carry out several demonstrations showing that the property of quantum contextuality also plays a significant role. Quantum contextuality captures an oddity about measuring the properties of quantum objects. While the colour of a pen, say, isn’t affected by whether you measure it before or after measuring the length of the pen, for a quantum object, the results of measurements cannot be treated as pre-existing properties that are …