Can Wigner’s Friend Lie?

A thought experiment ask, is Quantum Awareness fundamental to the universe?

Harold Wimberly
6 min readDec 17, 2020

Scientist and genius Nikola Tesla said,”The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence.” I believe the reason why there seems to be a never ending debate about consciousness is because most scientist want consciousness to be an emergent property of interactions in the material brain and theories that suggest otherwise are roundly marginalized. Questions of a quantum mind has persisted in spite of this since the very foundations of quantum mechanics. Nobel prize winner Sir Roger Penrose, a Theoretical Physicist who many consider a genius based on his past works, is a proponent of a quantum mind theory called Orch Or that he came up with alongside Anesthesiologist Stuart Hameroff. This model connects consciousness to quantum phenomena like the collapse of the wave function that they say occurs in subunits of microtubules in the brain. These microtubules are like mini quantum computers and access what they call protoconsciousness that’s embedded in spacetime geometry at planck scales.

Orch Or and other theories of consciousness need to be looked at with an open mind. In this article, I want to talk about a thought experiment that I came up with called, Can Wigner’s Friend Lie? This thought experiment is a twist on the Wigner’s friend thought experiment by Nobel prize winning Physicist Eugene Wigner. Wigner’s friend says, his friend in a laboratory carries out a quantum measurement on a system like an electron or photon. In this case, he’s performing a polarization measurement on a photon and he will observe if the photon is in vertical or horizontal polarization. He carries out the measurement and writes down in his notebook that he measured vertical polarization of the photon at 1 PM. In the lab, Wigner’s friend has caused the wave function to “collapse.” For Wigner outside of the lab, it’s a different story. Wigner can look at the photon and a record of his friend’s measurement and do an interference measurement and measure interference. Wigner can conclude that his friend didn’t carry out a measurement in the lab and the wave function Wigner measures is in superposition according to the linearity of the quantum mechanical equations. So the laboratory is in a superposition that includes Wigner’s friend who measured verticlal polarization and Wigner’s friend who measured horizontal polarization. Wigner’s wave function didn’t collapse although the wave function for his friend in the lab clearly collapsed and he has written down a record of this result. Wigner can only carry out an interference measurement and measure interference as long as he doesn’t have any knowledge and isn’t conscious of his friend’s measurement. If his friend calls and says,”Hey Wigner, I measured vertical polarization.” Wigner can no longer measure interference. How is the quantum system aware of what Wigner knows or doesn’t know about it’s state?

A 2019 study published in the journal Science Advances called Experimental test of local observer independence, confirmed Wigner’s friend thought experiment on a microscopic scale. They set up a version of Wigner’s friend and the results of the experiment were in agreement with Wigner. When Wigner outside of the lab didn’t have knowledge of his friend’s results, he could measure interference. When he learned about the results of his friend’s measurement, he could no longer measure interference. It would take Wigner’s Uncle in a laboratory across the street to measure interference between Wigner, his friend in the lab and the quantum system. If quantum mechanics is universal and it applies to macroscopic systems as most Physicist believe, then an observer that’s a measuring apparatus or a human brain is in superposition when it interacts with a quantum system.

A new rule can look like this. When an observer interacts with a quantum system, the probabilities of that system “collapse” or are reduced to a single probable state in the observer’s reference frame. So probabilities of the quantum system “collapse” so to speak to one probable state for Wigner’s friend in the lab which is his reference frame. A universal wave function doesn’t collapse just the probabilities for the observer’s reference frame and the observer concludes that a measurement occurred. Outside of the lab, Wigner has all of the information that his friend in the lab lacks because Wigner doesn’t have knowledge of the outcome that his friend observerved in the lab. So Wigner can do an interference measurement and measure interference. If you extrapolate this outwards, it points to a superobserver(O’) that doesn’t interact with any systems and never becomes a part of Physicist Carlo Rovelli’s S+O system in his Relational quantum mechanics. All this superobserver sees is interference between all states. So it’s aware of all things. Awareness inside of spacetime has a self conscious experience when a system “collapses” in it’s reference frame.

So we need to redefine consciousness based on these results. Consciousness and awareness of consciousness are usually seen as the same thing. I think this experiment shows that they’re not. They define an observer in the paper as any system that can interact with a quantum system and store the state of that system in it’s memory. So an observer gains information about it’s environment or the quantum system when it interacts with it. By this definition, the universe, a measuring apparatus or a human brain is an observer. I would say you can be conscious of the state of a system but not aware that you’re conscious of the system’s state.

A non aware observer, like a measuring device, can store information in it’s memory about the state of a quantum system, but that information is what I call stored knowledge and it has to be extracted by something outside of the system. Human observers have awareness of consciousness. The information stored in it’s memory is what I call dynamic knowledge. This means we can extract and think about that information without the need of an external agent to extract the information. We can write books about it, build technologies and ask what does it mean? This awareness might originate from what I call Quantum Awareness. The recent Wigner’s friend experiment already provides evidence for Quantum Awareness. The quantum system seems to be aware when when an observer has knowledge or doesn’t have knowledge of it’s quantum state stored in it’s memory.

I have a strong QA postulate and a weak QA postulate. A weak QA postulate says this Quantum Awareness becomes more dynamic when it interacts with human brains. It becomes self awareness. A strong QA postulate would be a more robust Quantum Awareness that may be more self aware than we are. We can test this by a thought experiment I call,”Can Wigner’s Friend Lie?” It would essentially be the same set up as the Wigner’s friend experiments, but Wigner’s friend would call Wigner and say,”Hey Wigner, I measured horizontal polarization.” Wigner’s friend actually measures vertical polarization and the question is, can Wigner still measure interference when his friend lies to him about the results of his measurement? We already know that Wigner can’t measure interference once he has knowledge of his friend’s measurement. The question is, is this Quantum Awareness so robust that it even knows when Wigner is being lied to and he actually doesn’t have knowledge of the state of a quantum system even when Wigner doesn’t know he’s being lied to?

Work Cited

Experimental test of local observer independence. Science Advances. https://advances.sciencemag.org/content/5/9/eaaw9832

Wimberly, Harold. Can Wigner’s Friend Lie?

Wigner’s Friend Wikipedia. https://en.wikipedia.org/wiki/Wigner%27s_friend

Relational quantum mechanics Wikipedia. https://en.wikipedia.org/wiki/Relational_quantum_mechanics

Orchestrated objective reduction(Orch OR) Wikipedia. https://en.wikipedia.org/wiki/Orchestrated_objective_reduction

--

--