Determined, page 20
Since then, scientists have explored the potential of using quantum entanglement in computing (with people at Apple apparently making significant progress), in communication systems, maybe even in automatically receiving a widget from Amazon the instant you think that you’ll be happier owning one. And the weirdness just won’t stop—entanglement over long enough distances can also show nonlocality over time. Suppose you have two entangled electrons a light-year apart; alter one of them and the other particle is altered at the same instant . . . a year ago. Scientists have also shown quantum entanglement in living systems, between a photon and the photosynthetic machinery of bacteria.[*] You better bet that we’ve got free-will speculations coming that invoke time travel, entanglement between neurons in the same brain, and, as long as we’re at it, between brains.[9]
Quantum Tunneling
This one is a piece of cake conceptually, after all the preceding strangeness. Shoot a stream of electrons at a wall. As we know, each travels as a wave, superposition dictating that until you measure its location, each electron is probabilistically in numerous places at once. Including the really, really unlikely but theoretically possible outcome of one of those numerous places being on the other side of the wall, because the electron has tunneled through it. And, as it turns out, this can happen.
That’s it for this pitiful tour of quantum mechanics. For our purposes, the main points are that in the view of most of the savants, the subatomic universe works on a level that is fundamentally indeterministic on both an ontic and epistemic level. Particles can be in multiple places at once, can communicate with each other over vast distances faster than the speed of light, making both space and time fundamentally suspect, and can tunnel through solid objects. As we’ll now see, that’s plenty enough for people to run wild when proclaiming free will.
10
Is Your Free Will Random?
Quantum Orgasmic-ness: Attention and Intention Are the Mechanics of Manifestation
The previous chapter revealed some truly weird things about the universe that introduce a fundamental indeterminism into the proceedings. And from virtually the first moment this news got around, some believers in free will have attributed all sorts of mystical gibberish to quantum mechanics.[*] There are now proponents of quantum metaphysics, quantum philosophy, quantum psychology. There’s quantum theology and quantum Christian realism; in one tract in that vein, quantum mechanics is cited as proving that humans cannot be reduced to predictable machines, making for human uniqueness that aligns with the biblical claim that God loves each person in a unique manner. For the “I don’t believe in organized religion, but I’m a very spiritual person” crowd, there’s quantum spirituality and quantum mysticism. Then there’s New Age entrepreneur Deepak Chopra, who, in his 1989 book Quantum Healing, promises a pathway to curing cancer, reversing aging, and, heavens to Betsy, even immortality.[*] There’s quantum activism, which, as espoused by a New Age physicist in his seminars, “is the idea of changing ourselves and our societies in accordance with the principles of quantum physics.” There’s “quantum cognition,” “spin-mediated consciousness,” “quantum neurophysics,” and—wait for it—a “Nebulous Cartesian system” of oscillations and quantum dynamics, explaining our freely choosing brains. And as a branch that particularly gets under my skin, there’s quantum psychotherapy, a field where one paper proposes that clinical depression is rooted in quantum abnormalities in the fatty acids found in the membranes of platelet cells; gain hope from the knowledge that there are folks pursuing this angle to help you, should you feel suffocatingly sad day after day. Meanwhile, the same journal contains a paper aiming to aid the treatment of schizophrenia sufferers, entitled “Quantum Logic of the Unconscious and Schizophrenia” (in which quantum comprises 9.6 percent of the words in the paper’s abstract). I’m not gonna lie—I’m not a big fan of folks touting crap like this concerning people in pain.[1]
The nonsense has some consistent themes. There’s a notion that if particles can be entangled and communicate with each other instantaneously, there is a unity, a oneness that connects all living things together, including all humans (except for people who are mean to dolphins or elephants). The time travel spookiness of entanglement can be hijacked with the idea that there is no unfortunate event in your past that cannot, in theory, be gone back to and fixed. There’s the theme that if you can supposedly collapse a quantum wave just by looking at it, you can achieve nirvana or go into the boss’s office and get a raise. According to the same New Age physicist, “The material world around us is nothing but possible movements of consciousness. I am choosing moment by moment my experience.” There is also the usual trope that whatever quantum physicists found out with their high-tech gizmos merely confirms what was already known by the Ancients; lotus positions galore. And near-villainous anti-grooviness comes from “materialists” with their “classical physics”[*]—“these elitists who dictate people’s experiences of meaning.” All this infinite potential is one big blowout salute to the renowned New Age healer Mary Poppins.[*],[2]
Some problems here are obvious. These papers, which are typically unvetted and unread by neuroscientists, are published in journals that scientific indexes won’t classify as scientific journals (e.g., NeuroQuantology) and are written by people not professionally trained to know how the brain works.[3]
But now and then, one’s critique of this thinking has to accommodate someone who knew how the brain works, bringing us to the challenging case of the Australian neurophysiologist John Eccles. He wasn’t just a good, or even a great, scientist. He was Sir John, Nobel laureate, who pioneered understanding in the 1950s of how synapses work. Thirty years later, in his book How the Self Controls Its Brain (Springer-Verlag, 1994), Eccles posited that the “mind” produces “psychons” (i.e., fundamental units of consciousness, a term previously mostly used in cheesy science fiction), which regulate “dendrons” (i.e., functional units of neurons) through quantum tunneling. He didn’t merely reject materialism in favor of dualism; he declared himself a “trialist,” making room for the category of soul/spirit, which freed the human brain from some of the laws of the physical universe. In his book Evolution of the Brain: Creation of the Self (Routledge, 1989), an unironic amalgam of spirituality and paleontology, Eccles tried to pinpoint when this uniqueness first evolved, which hominin ancestor gave birth to the first organism with a soul. He also believed in ESP and psychokinesis, querying new lab members whether they shared these beliefs. By my student days, the mention of Eccles, with his religious mysticism and embrace of the paranormal, elicited nothing but eye-rolling. As a scathing New York Times review of Evolution of the Brain concluded, Eccles’s descent into spirituality invited “Ophelia’s lament for Hamlet, ‘O! what a noble mind is here o’erthrown.’ ”[*],[4]
Obviously, it’s not sufficient for me to reject the idea that quantum indeterminacy is an opening for free will merely by citing the paucity of neuroscientists thinking this way, or by performing the Dirge for Eccles. Time to examine what I see as, collectively, three fatal problems with the idea.
Problem #1: Bubbling Up
The starting point here is the idea that quantum effects, down there at the level of electrons entangling with each other, will affect “biology.” There is precedent for this concerning photosynthesis. In that realm, electrons that have been excited by light are impossibly efficient at finding the fastest way to move from one part of a plant cell to another, seemingly because each electron does this by being in a quantum superposition state, checking out all the possible routes at once.[5]
So that’s plants. Trying to pull free will out of electrons in the brain is the immediate challenge—can quantal effects bubble upward, amplify in their effects, so that they can influence gigantic things, like a single molecule, or a single neuron, or a single person’s moral beliefs? Nearly everyone thinking about the subject concludes that it cannot happen because, as we’ll soon cover, quantal effects get washed out, cancel each other out in the noise—the waves of superposition “decohere.” As summarized nicely by the title of a book by physicist David Lindley, Where Does the Weirdness Go? Why Quantum Mechanics Is Strange, but Not as Strange as You Think (Basic Books, 1996).
Nonetheless, people linking quantum indeterminacy with free will argue otherwise. Their challenge is to show how any building block of neuronal function is subject to quantum effects. One possibility is explored by Peter Tse, who considers the neurotransmitter glutamate, where the workings of one of its receptors requires popping a single atom of magnesium out of an ion channel that it blocks. In Tse’s view, the location of the magnesium can change in the absence of antecedent causes, because of indeterminate quantal randomness. And these effects bubble up further: “The brain has in fact evolved to amplify quantum domain randomness . . . up to a level of neural spike timing randomness” (my emphasis)—i.e., up to the level of individual neurons being indeterminate. And the consequences then ripple upward further into circuits of neurons and beyond.[6]
Other advocates have also focused on quantal effects occurring at a similar level, as captured in one book’s title—Chance in Neurobiology: From Ion Channels to the Question of Free Will.[*] Psychiatrist Jeffrey Schwartz of UCLA views the level of single ion channels and ions as fair game for quantal effects: “This extreme smallness of the opening in the calcium ion channels has profound quantum mechanical implications.” Biophysicist Alipasha Vaziri of Rockefeller University examines the role of “non-classical” physics in determining which type of ion flows through a particular channel.[7]
In the views of anesthesiologist Stuart Hameroff and physicist Roger Penrose, consciousness and free will arise from a different part of neurons, namely microtubules. To review, neurons send axonal and dendritic projections all over the brain. This requires a transport system within these projections to, for example, deliver the building blocks for new copies of neurotransmitter or neurotransmitter receptors. This is accomplished with bundles of transport tubes—microtubules—inside projections (this was briefly touched on in chapter 7). Despite some evidence that they can themselves be informational, microtubules are mostly like the pneumatic tubes in office buildings circa 1900, where someone in accounting could send a note in a cylinder downstairs to the folks in marketing. Hameroff and Penrose (with papers with titles such as “How Quantum Biology Can Rescue Conscious Free Will”) focus in on microtubules. Why? In their view, the tightly packed, fairly stable, parallel microtubules are ideal for quantum entanglement effects among them, and it’s on to free will from there. This strikes me as akin to hypothesizing that the knowledge contained in a library emanates not from the books but from the little carts used to transport books around for reshelving.[8]
Hameroff and Penrose’s ideas have gained particular traction among quantum free-willers, no doubt in part because Penrose won the Nobel Prize in Physics for work concerning black holes and also authored the 1989 bestseller The Emperor’s Mind: Concerning Computers, Minds, and the Laws of Physics (Oxford University Press). Despite this firepower, neuroscientists, physicists, mathematicians, and philosophers have pilloried these ideas. MIT physicist Max Tegmark showed that the time course of quantum states in microtubules is many, many orders of magnitude shorter-lived than anything biologically meaningful; in terms of the discrepancy in scale, Hameroff and Penrose are suggesting that the movement of a glacier over the course of a century could be significantly influenced by random sneezes among nearby villagers. Others pointed out that the model depends on a key microtubule protein having a conformation that doesn’t occur, on types of intercellular connections that don’t happen in the adult brain, and on an organelle in neurons being in a place where it isn’t.[9]
So, this savaging aside, can quantal effects actually bubble up enough to influence behavior? The indeterminacy that releases magnesium from a single glutamate receptor doesn’t enhance excitation across a synapse all that much. And even major excitation of a single synapse is not enough to trigger an action potential in a neuron. And an action potential in one neuron is not enough to make a signal propagate through a network of neurons. Let’s put some numbers behind these facts. The dendrite in a single glutamatergic synapse contains approximately 200 glutamate receptors, and remember that we’re considering quantal events in a single receptor at a time. A neuron has, conservatively, 10,000–50,000 of those synapses. Just to pick a brain region at random, the hippocampus has approximately 10 million of those neurons. That’s 20–100 trillion glutamate receptors (200 x 10,000 x 10,000,000 = 20 trillion, and 200 x 50,000 x 10,000,000 = 100 trillion).[*] It is possible that an event having no prior deterministic cause could alter the functioning of a single glutamate receptor. But how likely is it that quantum events like these just happen to occur at the same time and in the same direction (i.e., increasing or decreasing receptor activation) in enough of those 20–100 trillion receptors to produce an actual neurobiological event that has no prior deterministic cause?[10]
Apply some similar numbers in the hippocampus to those putative consciousness-producing microtubules: Their basic building block, a protein called tubulin, is 445 amino acids long, and amino acids average out to close to 20 atoms each. Thus, around 9,000 atoms in each molecule of tubulin. Each stretch of microtubule is made up of 13 tubulin molecules. Each stretch of axon contains about 100 bundles of microtubules, each axon helping to make the 10,000–50,000 synapses in each of those 10 million neurons. Again with the zeros.
This is the bubbling-up problem in going from quantum indeterminacy at the subatomic level up to brains producing behavior—you’d need to have a staggeringly large number of such random events occurring at the same time, place, and direction. Instead, most experts conclude that the more likely scenario is that any given quantum event gets lost in the noise of a staggering number of other quantum events occurring at different times and directions. People in this business view the brain not only as “noisy” in this sense but also as “warm” and “wet,” the messy sort of living environment that biases against quantum effects persisting. As summarized by one philosopher, “The law of large numbers, combined with the sheer number of quantum events occurring in any macro-level object, assure us that the effects of random quantum-level fluctuations are entirely predictable at the macro level, much the way that the profits of casinos are predictable, even though based on millions of ‘purely chance’ events.” The early-twentieth-century physicist Paul Ehrenfest, in the theorem bearing his name, formalizes how as one considers larger and larger numbers of elements, the nonclassical physics of quantum mechanics merges into old-style, predictable classical physics.[*] To paraphrase Lindley, this is why the weirdness disappears.[11]
So one glutamate receptor does not a moral philosophy make. The response to this by quantum free-willers is that various features of nonclassical physics can coordinate quantum events among a lot of constituents in the nervous system (and some posit that quantum indeterminacy bubbles up to some extent and meets chaoticism there, piggybacking all the way up to behavior). For Eccles, quantum tunneling across synapses allows for the coupling of networks of neurons in shared quantum states (and note that implicit in this idea and those to follow is that entanglement occurs not just between two particles, but between whole neurons as well). For Schwartz, quantum superposition means that a single ion flowing through a channel is not really singular. Instead, it is a “quantum cloud of possibilities associated with the [calcium] ion to fan out over an increasing area as it moves away from the tiny channel to the target region where the ion will be absorbed as a whole, or not absorbed at all.” In other words, thanks to particle/wave duality, each ion can have coordinated effects far and wide. And, Schwartz continues, this process bubbles upward to encompass the whole brain: “In fact, because of uncertainties on timings and locations, what is generated by the physical processes in the brain will be not a single discrete set of non-overlapping physical possibilities but rather a huge smear of classically conceived possibilities” now subject to quantum rules. Sultan Tarlaci and Massimo Pregnolato cite similar quantum physics in speculating that a single neurotransmitter molecule has a similar cloud of superposition possibilities, binding to an array of receptors at once and lassoing them into collective action.[*],[12]
So the notion that random, indeterministic quantum effects can bubble all the way up to behavior strikes me as a little dubious. Moreover, nearly all the scientists with the appropriate expertise think it is resoundingly dubious.
Somewhere around here it seems useful to approach things on a more empirical level. Do synapses ever actually act randomly? How about entire neurons? Entire networks of neurons?
Neuronal Spontaneity
As a brief reminder: When an action potential occurs in a neuron, it goes hurtling down the axon, eventually reaching all of the thousands of that neuron’s axon terminals. As a result, packets of neurotransmitter are released from each terminal.
If you were designing things, maybe each axon terminal’s neurotransmitters would be contained in a single bucket, a single large vesicle, which would then be emptied into the synapse. That has a certain logic. Instead, that same amount of neurotransmitter is stored in a bunch of much smaller buckets, and all of them are emptied into the synapse in response to an action potential. Your average hippocampal neuron that releases glutamate as its neurotransmitter has about 2.2 million copies of glutamate molecules stored in each of its axon terminals. In theory, each terminal could have all of those copies in our single big bucket vesicle; instead, as noted before, the terminal contains an average of 270 little vesicles, each containing about eight thousand copies of glutamate.
