Eugene Wigner, the Hungarian-born American physicist, one of the early pioneers of quantum physics who received a Nobel Prize for his contribution, famously argued that individual people view reality through a different lens.
Wigner expanded on the Copenhagen Interpretation, which argued that a subatomic particle is not a solid and stable thing, but exists simply as a potential of any one of its future selves – or what is known by physicists as a ‘superposition’, or sum, of all probabilities, like a person staring at himself in a hall of mirrors.
The only thing dissolving this little cloud of probability into something solid and measurable was discovered to be the involvement of an observer.
Once scientists decided to have a closer look at a subatomic particle by taking peek or making a measurement, the subatomic entity that existed as pure potential would ‘collapse’ into one particular state.
The implications of these early experimental findings were profound: living consciousness somehow was the influence that turned the possibility of something into something real. The moment we looked at an electron or took a measurement, it appeared that we helped to determine its final state.
This suggested that the most essential ingredient in creating our universe is the consciousness that observes it. Several of the central figures in quantum physics argued that the universe was democratic and participatory – a joint effort between observer and observed.
Many scientists, including Einstein, resisted this interpretation. To test the ‘ridiculous’ implications of this idea, as he put it, Erwin Schrödinger, another quantum architect, devised his famous cat experiment, where a cat is locked up in a steel chamber rigged up in such a way that it may or may not release a poison. This would mean, said Schrödinger, that you’d have to consider the cat both dead and alive – until an observer manages to peek inside the box.
This thought experiment was supposed to demolish the quantum physics’s ‘blurred model,’ said Schrödinger, for representing reality. “There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks,” he said.
But Wigner had an answer to that. Wigner designed a thought experiment called ‘Wigner’s friend.’ He imagined a photon, which was in a state of superposition until measured by a friend in a lab, at which point it collapses down to a single state.
But since Wigner is outside the lab, he has no information about the photon or his friend’s measurement and so has to conclude that both are still in a state of superposition of all possible outcomes.
He can even perform his own experiment with the photon that maintains the photon in a state of superposition. He ends up with a different version of reality than his friend does.
The central premise of this thought experiment was that Wigner and his friend both see a different nature of reality. Scientists have used his experiment to indulge in many lofty and highly speculative arguments about whether there is such a thing as an objective ‘out there’ that we all see.
The experiment for real
But now with new quantum technologies enabling scientists to actually carry out this experiment for real, a new study shows that Wigner was onto something.
Massimiliano Proietti and his colleagues at Heriot-Watt University in Edinburgh have created two versions of the same reality and demonstrated that they cannot be reconciled – showing that there is no such thing as objective facts about an experiment.
Their work started when Caslav Brukner, at the University of Vienna, devised a modern-day version of Wigner’s thought experiment using six different photons. Then Proietti and his colleagues worked out a way to actually carry it out.
They used the six photons in one experiment and had Alice’s ‘friend’ measure one photon and store the result. Then ‘Bob’s friend’ performs another type of measurement on the state of the photon plus his friend’s measurement to determine if the measurement and the photon are in a superposition.
The result: both Alice’s friend and Bob’s friend are right, and both realities can co-exist, even if they have irreconcilable differences.
No out there out there
This little study has explosive implications. It suggests that the entire idea that we have one reality that we can agree on must be wrong.
It also has major implications for science. “The scientific method relies on facts, established through repeated measurements and agreed upon universally, independently of who observed them,” say Proietti and his colleagues.
That entire idea has been blown up – this time. . . by science.
The bottom line: there is no set out there out there.
This suggests not only that the observer brings the observed into being, but also that nothing in the universe exists as an actual ‘thing’ independently of our perception of it.
It implies that reality is not fixed, but mutable and utterly personal to each of us.
You never see what I see.
The biggest implication of all: we’ve all got to come up with a very different way to discuss things with each other.