Saturday, September 16, 2017

The Brain As Quantum Computer


Recently I had the opportunity to watch southern African White-necked crows while they were watching me. I was taking afternoon tea (and eating rusks) on the patio overlooking a beautiful valley in the hills near Mbabane. Crows are smart and these are among the smartest. One sat on the roof of the next house staring at me convinced that at some point, I would grow careless and give him or her a chance to steal something, perhaps something to eat. As I was ever-vigilant, eventually they flew off over the valley, soaring and dipping in very real time. As I watched, I thought about the complex calculations that a bird must make moment-to-moment to move so quickly through three-dimensional space. They must keep track of where they are, where to go, how to get there. Knowing each requires entire subsets of information – such as (for where to go), where they saw food or last saw food or might find food while watching for anything that might require evasive action. These calculations must be solved each fraction of a second. I then thought this must be true for any animal with a brain (or nervous system). Neural systems allow the organism to move through, and react to, the environment rather than obey simple tropisms or merely be buffeted about by the external environment. The more complicated the neural system – reaching a peak of networks of networks to the 4th or 5th power (or beyond) running in our human brains – the more complex the information that can be stored and manipulated. A classical view of the human brain would start with the 500 trillion synapses of the adult brain’s hundred billion neurons. Now that is a lot of synapses. But think about how much information is stored there in language, knowledge, experience, memories and everything else that makes each individual unique and utterly complex.

I’ve speculated in this space about quantum consciousness, the production of mind from brain through “collapsing the wave functions apprehended from the perceptual flow. While watching the crows, I realized that the brain must function as a quantum computer and not as a classical system. The notion that quantum processes mix with (or form) consciousness is called “orchestrated objective reduction.” It rests on the possibility that the microtubules in nerve cells are small enough to contain quantum states. The brain accounts for just two percent of the human body’s mass but utilizes around 20% of its energy. It basically is like having a 20 watt bulb in our head shining all the time. This energy could be powering the creation and persistence of entangled states inside the microtubules of every cell. In this way, the neural organization of the brain would be the maintenance of a complex, constantly refreshed, while constantly changing, global entangled state. The collapse of the highest level of this entangled state-of-states coincides with consciousness. Inside our heads, this quantum computer has storage and calculating power well beyond what would be true if our brains functioned simply along classical physics lines. It may produce what we experience as consciousness. Or, collapse may come through the decisions that we – the “ghost” in the machine, acting as the internal observer – make in each moment as the crow flies.