Image: Looking underneath the wavefunction—represented by the Greek letter “psi”—in the search for quantum reality.
Original Published Date: 
Thursday, March 5, 2015

Research supported by the ARC Centre of Excellence for Engineered Quantum Systems and Quantum Computation and Communication Technology at The University of Queensland has made major progress in answering a long-standing dilemma in quantum mechanics: Is Schrödinger’s cat really alive and dead at the same time? Using four-dimensional states of photons, and subjecting them to very precise measurements, they ruled out the popular view that describing the cat as dead and alive is just due to a lack of knowledge about its real state. As with all objects in quantum physics, the cat is described by the quantum wavefunction. Lead author and UQ PhD student, Mr Martin Ringbauer, said that their approach tested whether the competing interpretations of the wavefunction can explain why we cannot tell quantum states apart with certainty, which is a central feature of quantum mechanics. “Our results suggest that, if there is objective reality, the wavefunction corresponds to this reality,” Mr Ringbauer said. In other words, Schrödinger’s cat really is in a state of being both alive and dead.

Media issued by The University of Queensland


Photo credit: 

Image credit: Benjamin Duffus and Martin Ringbauer