A cell has about 42 million protein molecules working together in the most complex system known to mankind. It has been called the third infinity (Denton, 2020) because just as the universe is bigger than we know, and quantum events are smaller, the cell is more complex than we can imagine. It is so complex that the chances that trillions of atoms in a primal stew randomly produced millions of proteins that randomly formed a self-replicating cell is effectively zero. The probability is beyond astronomical, and the steps of evolution didn’t help, as proteins decay in the earth environment, so how life overcame the physical odds to emerge is a mystery.
Evolution needed help, so biologists suggested an unexpected source. The emerging field of quantum biology holds that the mysteries of biology, like those of physics, are explained by quantum theory (McFadden & Al-Khalili, 2018). Quantum effects on the atomic scale helped stars and galaxies evolve, but that they also affected the macro-world of cells was unexpected:
“On the face of it, quantum effects and living organisms seem to occupy utterly different realms. The former are usually observed only on the nanometer scale, surrounded by hard vacuum, ultra-low temperatures and a tightly controlled laboratory environment. The latter inhabit a macroscopic world that is warm, messy and anything but controlled. A quantum phenomenon such as ‘coherence’, in which the wave patterns of every part of a system stay in step, wouldn’t last a microsecond in the tumultuous realm of the cell. Or so everyone thought. But discoveries in recent years suggest that nature knows a few tricks that physicists don’t: coherent quantum processes may well be ubiquitous in the natural world.” (Ball, 2011), p272.
Physics uses quantum events to explain impossible physical events, though it denies they exist, so biology can use it to explain impossible biological events. The premise is simple, that life does what it can to survive, so if quantum events do what physical events can’t, it will use that power if it can, and it had billions of years to discover ways to do so. Biologists then just had to look to find quantum effects in many functions:
“…something quantum mechanical is going on inside living cells, whether it’s in photosynthesis, whether it’s in enzyme catalysis,[16] [17] [18] whether it’s in mutations of DNA,[19] [24] even more controversially the way we smell, the theories of olfaction,[25] or magnetoreception, the way certain animals can sense the Earth’s magnetic field, the chemical compass that allows them to detect the orientation of the field relies on quantum effects, quantum entanglement.[26] [27] [28]” (Al-Khalili & Lilliu, 2020).
For example, plants convert sunlight into energy to sustain all complex life on earth by photosynthesis, which bacteria discovered over three billion years ago. The electric motors of today are about 25% efficient, losing the rest to heat, but low-light bacteria convert nearly 100% of light energy into chemical energy (Magdaong et al., 2014). According to Carnot’s law, a heat engine with this efficiency is impossible, but bacteria have a quantum heat engine that does what classical physics forbids (Al-Khalili & McFadden, 2014) p310, because life evolved to use quantum effects:
“… natural selection has come up with ways for living systems to naturally exploit quantum phenomena” (O’Callaghan, 2018).
Photosynthetic bacteria use tightly-packed molecules called chromophores to detect light. These little antennae then pass it to reaction centers where it is converted into chemical energy for use. When one of them registers a photon, the excitation must pass through a forest of antennae to reach the nearest reaction center, but:
“The problem, of course, is which route this energy transfer should take. If it heads in the wrong direction, randomly hopping from one molecule to the next in the chlorophyll forest, it will eventually lose its energy rather than delivering it to the reaction center.” (Al-Khalili & McFadden, 2014), p126.
The photon pulse decays in nanoseconds, so it should often go down a dead-end and die out, but instead almost every photon reaches a reaction center. Bacteria in the dark depths of the sea survive by capturing all the specks of light that reach them, but how?
The answer that evolution provided was to vibrate their light antennae in synchrony to give what are called quantum beats (Engel, 2007), that in turn entangle their electro-magnetic fields (Maiuri, 2018). In physics, entanglement is a fragile quantum state that occurs in atoms or near absolute zero but should quickly collapse in a warm cell. Yet it only requires identical matter entities whose quantum fields superpose (Lo Franco & Compagno, 2016), and densely packed chromophores vibrating in synchrony satisfy this requirement, so they entangle.
Entities that entangle essentially become one entity (Aspect et al., 1982), a coherent ensemble that acts as one not just individual parts (3.8.5). Hence when a photon hits a bacteria, it’s entangled antennae all restart and again entangle. This quantum state lets the excitation explore all the paths around it at once, until it collapses at a reaction center. Without entanglement, one antenna would pass the photon energy down one path, but with entanglement, all the antennae pass it on down all possible paths at the same time. Quantum entanglement then explains how bacteria harvest light with near 100% efficiency, by using many antennae to process a photon rather than just one.
Note that quantum beats only maintain the entanglement very briefly, but it is enough:
“Coherent quantum beats have been observed in most light harvesting systems, where the coherences are stable over a time scale that is commensurate with the relevant energy transfer times.” (Scholes Group, 2018).
Instead of one chromophore molecule observing one photon, quantum entanglement lets many observe it as one for a brief time, a unification that increases the ability to observe earlier defined as consciousness. Cells then solve their binding problem by introducing synchronous vibrations, but how do they do that?