Entanglement is the phenomenon in which two particles from the same origin remain connected, even if they move far apart in time and space. If something affects one particle, it will also affect all the particles with which it is entangled. This means that measuring a property of one particle instantly tells you something about its entangled partner/s, no matter how distant they are.
Albert Einstein famously called entanglement ‘spooky action at a distance,’ and the phenomenon has been demonstrated in a range of systems, including photons, electrons and trapped ions. Today, entanglement is no longer just a curiosity: it underpins emerging technologies such as quantum computers, ultra-secure quantum communication networks and next-generation sensors. For instance, in quantum computing, entanglement is used to manipulate multiple qubits in a single operation, rather than individually. This allows multiple calculations to be performed simultaneously.
However, it was unknown whether quantum entanglement remains intact under more extreme conditions – such as the short-lived particles produced during highly energetic collisions. To test this, an international collaboration used the ATLAS experiment at CERN’s Large Hadron Collider (LHC) near Geneva, Switzerland. The team looked for entanglement in an entirely new setting: pairs of Z bosons that exist for only a fraction of a second before decaying.
To read more, click here.