Scientists at the University of Geneva found a way to use quantum entanglement to measure distant particles together.
Entanglement connects particles across distances, like an invisible link. One particle’s state instantly shows the other’s state. This research helps quantum communication and computing. In these fields, information appears only when measured. The scientists also made a guide. It sorts different measurements and shows how many entangled particles each needs. They published this study in Physical Review X.
Measuring quantum particles is hard. When tools measure particles, they can change the particles’ properties. This makes accurate measurements tricky. Scientists study quantum entanglement or superposition. Superposition means a particle exists in multiple states at once. These properties help quantum cryptography and computing.
Invisible connections drive progress
Entanglement is key for new technologies. Quantum communication encodes information in particles, like photons. To read the information, scientists measure the particles. The study shows scientists can measure separate particles together. The particles don’t need to touch. The measurement tools share entangled particles. This links the tools and particles. Measuring one particle reveals the other’s state instantly, no matter the distance.
"A central question is whether it’s possible to perform a joint measurement on two or more separate particles - each carrying part of the information - without physically bringing them together," notes a press release. Simple but important measurements "can be performed on separate particle systems, as long as the measurement devices share entangled particles."
Some measurements need more entangled particles. Others need fewer. The scientists created a system to classify measurements. This catalog explains which measurements need how many entangled particles. This helps plan quantum experiments. The findings could improve quantum communication. They could also help quantum computing. In regular computing, machines split tasks and combine results. Quantum computers might do this too. Each computer measures its part. The results combine without moving data. This avoids centralizing information. The scientists want to explore this further. Their work builds a foundation for better quantum technologies.