In recent years, matzah seems tastier to me. I don’t know whether it’s because I’ve got so many good associations with the other tastes of the holiday, including brisket, matzah brie, gefilte fish, and macaroons. Or maybe the shmurah (super-orthodox watched-while-it’s-baked) matzah we now get is better than Manischevitz of yore. But I’m probably fooling myself. Matzah really is the bread of affliction. It’s dusty, dry, brittle, tasteless, mean fare. Every year, I ask the ancient theological questions plaguing the Jews, “Does matzah ever go stale? Would anyone know? Why would such a dispiriting food be so central to the most delightful, and perhaps the most important, Jewish holiday? Why is matzah so important that even the Torah calls Passover The Holiday of Matzahs?“
Matzah is itself and an invitation to interpretation
Like many things in Jewish ritual, matzah is both itself and symbolic of many other things all at once. When we eat matzah, we collapse the 3330 years between us and our slave ancestors by reliving the sensation of the Children of Israel, who ate matzah on the night before the Exodus. They then ate it a second time when they didn’t have time to let the bread rise before we exited Egypt. We can taste what it’s like to be slaves who cannot choose the bread they eat. Matzah means itself.
For something so flat, matzah also has so many layers of meaning that it seems to be a paradox about layering. It is flat but infinitely deep. During the seder, we focus on the difference between bread and matzah and bring out the symbolism that makes it the centerpiece of Passover. This is one of the beauties of the seder: along with teaching children the central story of our people, it also teaches them a way of thinking. The matzah and the other objects on the seder plate multiply meanings, which we somehow hold in parallel in our minds like a symphonic theme weaving in and out of different instruments and keys through the course of a performance. Somehow, the meanings don’t clash. They magically harmonize and make each other grander. Even more amazingly, after all the sermons, the things in front of us, the egg, greens, bitter herbs, matzah, charoset and wine remain fully themselves. In the end, though, we still get to eat them, to ingest the sermon.
Even at my grandfather’s home, where he blazed through the seder in Hebrew (he was born in Jerusalem in 1899), Passover seemed like deliverance from the slavery of school. Compared to the arguments of the seder, school was all rote learning and dull algebra, a race to get the one right answer. In school, the signifier meant one thing only, a simple tune played on a three-penny pipe. The seder was a tutorial about the promised land of full-throated, orchestral argument, where even children are urged to join in. The other grand traditions of our seder – the red-faced shouting about politics and the cutthroat 25 cent pinochle game at the end – all seemed to flow from the sages in Bnei Brak who tried to one-up each other over the number of plagues. Such disagreements, as Rav Kook said, are a noisy route to universal peace.
That’s why this year I was so childishly excited to discover a new sermon in matzah that harmonized with all the others. By looking at the most literal physics of its nature, this is what I saw:
Matzah is a sermon on God’s absence. By noting matzah is not bread, we open a door, inviting Him to enter the home during the seder. It is the secret twin of Elijah’s Cup, asking the same question left by the untouched wine in Elijah’s cup: Where is He?
The Matzah Sermons
The Matzah Sermon has many versions.
We forego bread because the difference between bread and matzah is inflation, the chewy fullness that grants satisfaction. We should beware our own puffed-up egos and liberate ourselves from enslavement to the things that make us too swollen with pride and arrogance.
The difference between bread and matzah is our taste for sensuality, so beware enslavement to material things that give us sensuous pleasure. As the Zohar says, the Hebrew word for “taste” – tam – also means “reason.” Don’t let temptations of the body blind you to the truths that come from your higher intellect.
The difference between bread and matzah is time: if you let even flour and cold water sit for eighteen minutes, it will begin to ferment. Matzah was hurried because the Israelites had to stay small in the night. So they ate humble bread while the terrible tenth plague, the slaying of the first born, passed over. Then they had to hurry because the next morning they were rushing out of Egypt. They made and ate matzah a second time. Rush towards redemption. Yearn for freedom.
The difference between bread and matzah is we eat bread three times a day through the year, but “on this night, only matzah.” Beware enslavement to routine habits or desires.
Matzah is bread without spirit, its golem. Beware idolatries, worshiping things that are mere flat objects, empty of true dimension or inner meaning, else you will become like matzah, flat and de-spirited.
Many hosts answer the invitation to interpret by writing fashionable causes du jour into their Haggadah. Fifty years ago, the spirit of Passover helped fuel the civil rights movement. Now, almost every homegrown haggadah now includes passages about Martin Luther King, or genocide and slavery in other regions of the world, or calls for equality for transgender people and an end to the oppression of animals by us Pesach carnivores, or analogies between an unpopular president and pharaoh, or even, chas v’chalilah, insanely misguided pleas for Israel to end its so-called apartheid.
For that reason, the sermons that move me the most are not political but ones that drive to mystical implications. Matzah reminds us that God himself intervened in nature and time to free us. Because in Egypt we had only flattened slave-perception, we, and the world, had to witness His miracles firsthand to be convinced. At other times, He works only through nature, quietly if ubiquitously. In the kabbalistic tradition, matzah represents the absence of this true knowledge and understanding of God.
Metaphysics in the physics of matzah
It was my idolatrous love of sushi that drove me to look at the physics of matzah.
This year, I thought we would fulfill the theme of liberation by “going Sephardi”: giving ourselves permission to eat rice on Passover. Since Talmudic time, all Jews who follow strict practices have agreed to avoid the five grains that expand when cooked – oats, barley, spelt, wheat and rye. But a schism arose in the last five centuries between the Ashkenazi, Jews of Europe and the Sephardi, Jews descended from exiles from the Spanish Inquisition (and then most Arab countries in Northern Africa and the East). Maybe because they lived where the weather made them grumpier, Ashkenazi Jews constructed the anti-inflation rule strictly and also forbad lentils, beans, corn, and rice. The Sephardi continue to enjoy them. I voted for rice, largely because I had a fantasy about kosher for Passover sushi.
I lost. But to defend my unpopular position, I was driven to science to try to find out what exactly caused the dread “inflation.” What I discovered didn’t help me win my case, but it opened up an incredible vista about the difference between bread and matzah incarnated in the biophysics of yeast.
Matzah and bread both are essentially wheat flour and water. Outside the seder, on Passover we can add eggs and salt for flavor, and some matzahs that are KLP (kosher for Passover) even include oil, honey, juice, or even wine, as long as they don’t make the dough rise. But during the seder proper, we are supposed to eat only “poor matzah”: flour and water. To make bread, you need yeast.
Humans recognized and harnessed the magical properties of yeast even before they could write. Yeast makes flour and water into bread. It also makes grapes into wine. It seems to add life to inert foodstuffs, transforming them magically into something else alive. Grape juice is just a soft drink. But wine is literally a spirit. A cracker is a good delivery platform for dip, but bread is the staff of life itself. By ingesting wine and bread, we take some of that magic into us. Bread sates. Wine leavens our spirit. It’s no wonder bread and wine were worshiped by the ancients and are central to many religious rituals.
Though the technology of yeast has been perfected, the science of yeast still holds mysteries and surprises. To put it another way, we know the mechanics of how yeast work down to the molecular level, but we’re not completely sure how it performs its magic.
The quantum physics of yeast
Yeast is a single-celled living creature. When we let these critters feed on their favorite food, sugar or anything that contains sugar or carbohydrates, they digest it into sugar’s components: energy, alcohol, carbon dioxide, and some residue molecules that add flavors. The process the ancients observed was bubbling, rising fermentation. When we bake bread, the heat evaporates alcohol produced by the yeast into gas bubbles that expand and burst, contained by the sticky dough. This gives bread its texture. In the cooler processing of wine (and beer), the alcohol is completely contained in the liquid for our pleasure.
All this you probably learned in high school chemistry as an example of enzymatic activity. But what they didn’t teach us, because chemistry isn’t etymology, is that “enzyme” is just the Greek for “in yeast.” And what you didn’t learn, because chemistry didn’t know, is how yeast, or enzymes, are the gateway between the living and the inert, literally life and death.
The new science of quantum biology has started to answer the question of how yeast performs this magic.
Yeast is the ur-type of all enzymes. Enzymes are present in all living things, in every living cell, and in every process that sustains life: digestion, neural action, making new cells and repairing old ones (growth and healing), reproduction, and so on. There is an eternal philosophical battle between materialists and vitalists. Materialists believe the universe and everything in it, including humans and human consciousness, is a vast machine. It is made up only of physical things and the physical processes or forces between them. Vitalists argue that there is a meta-physical force in the universe that animates all life, a force that cannot be reduced to mechanical explanations. Human consciousness particularly illustrates the problem and limitation of materialism. Fundamentalist materialists argue that everything can be explained ultimately, by self-consistent systems of reason, like logic or mathematics. Religious vitalists argue that the metaphysical force is divine.
Although yeast is a living thing, enzymes have until recently seemed to be purely chemical machines. In the debate between materialists and vitalists, enzymes have been the best proof for the materialist view of life. They seem to explain how life is introduced into inert matter without resort to non-mechanistic explanations. Until now.
It turns out that enzymes require quantum effects to do their work, and quantum mechanics defies the materialist view of the cosmos. At its best, quantum mechanics defies logic, though we’ve learned to use them in MRIs and computer chips. At its worst, every quantum process requires an aware being to watch it work in order for it to be real.
I know to most of you unfamiliar with it this claim for quantum mechanics seems just weird. There’s no way to explain any quantum process without over-simplifying it or resorting to analogies which dangerously distort its actual, full-on weirdness. Many have tried and some have succeeded. (See a very spare reading list at the end of this blog of some I think do the best job.) Let’s just say the quantum is profoundly counter-intuitive. But here are a few of the weird facts that you will need to know as we continue with our discussion of matzah. I leave it to you to discover whether you buy any of it yourself:
- Sub-atomic entities behave like both waves of energy and particles at the same time.
- A sub-atomic entity isn’t in any one specific place until you observe it. Then it seems to settle on one. (Uncertainty)
- A single sub-atomic particle can be in two places at once. But if you affect one, its other self will react, even if they are separated by millions of miles. (Superposition)
- They can pass through otherwise impassible-seeming barriers (quantum tunneling) and “travel” faster than the speed of light.
- When a subatomic particle is observed or measured, it “collapses” from its various possible quantum states into one state. Ie, it stops behaving quantumly and starts behaving classically. (Measurement)
To understand the quantum theology of matzah, the last aspect is the most important. Until now, biologists have been fairly content to leave the weirdness of the quantum world among physicists. They assumed there was an unbreachable barrier between the sub-atomic world of quantum weirdness and the macroscopic world of biology obedient to classical laws of physics. Thankfully (they believed) micro monkey business collapsed when it poked its head up into an organism because the complexity of the organism automatically “measured” (observed) it (though no one specified how). They now seem to be really wrong. It’s uncomfortable.
Resurrected by water, living yeast seems to make the inert come alive. Yeast works enzymatically to ferment the sugars in flour. It explodes the flat mound of dough and makes it rise as little bubbles of alcohol explode inside. It adds tastes by creating new molecules. But what was once thought to be a classical, if incompletely understood, mechanical process (catalysis) we now know requires quantum tunneling.
Quantum tunneling in yeast
Here’s the technical explanation: an enzyme in yeast takes a positively charged sub-atomic particle, the proton from the alcohol it has created, and transfers it to another molecule. This new molecule, with the addition of its extra proton, now has a positive charge. Like a magnet, it now attracts molecules carrying a negatively charged particle, the electron. So the new molecule the yeast created (called nicotinamide alcohol dehydrase or NADH) becomes a very effective carrier and releasor of electrons. With NADH, the ingredients can now perform their actions very quickly and efficiently. It’s like the brew now has an electric current running through it, with electrons able to hitch a ride and jump off when a chemical reaction needs an extra jolt of energy to make it happen.
So far so good. This is all safe, mechanical chemistry.
As it turns out, though, the speed at which electrons get transferred from alcohol to NAD+ to make NADH cannot be explained by classical chemistry. On the other hand, quantum tunneling, number three on our list of weird quantum effects above, can. Again, at the risk of over-simplifying, a subatomic particle can help an electron travel across barriers instantaneously by using its superpower of quantum tunneling. As this effect occurs among millions of molecules in the dough, it speeds up the process enough for biologists to say it must be involved. 
This neat explanation of the quantum role in enzymatic action leaves one huge mystery, though: In order for the transport of the electron to occur, it can’t be just a probability, and in order for it to be more than a probability, it has to be observed or measured. The probabilistic quantum behavior – the electron can be here or there and therefore nowhere at all, really – has to become classical behavior. I see it now. Until now, biologists, scientists and other materialists have maintained that the macroscopic bulk of the organism in which the quantum action occurs collapses any quantum craziness. I.e., the fact of the organism itself performs the “observing.” But that argument no longer holds water and even seems like a tautology, fabulous circular reasoning, because enzymes involve quantum action. Enzymes, and the quantum, is ubiquitous in every process of every cell in an organism. In fact, it seems to be the essence of life itself.
“Enzymes have made and unmade every living cell that lives or has ever lived. Enzymes are as close as anything to the vital factors of life. …. [T]he discovery that enzymes work by promoting the dematerialization of particles from one point in space and their instantaneous materialization in another provides us with a novel insight into the mystery of life.”
– Johnjoe McFadden, Jim Al-Khalili, Life on the Edge: The Coming of Age of Quantum Biology (Broadway Books, Jul 26, 2016) p. 97
There’s simply too much quantum funny business going on everywhere in a living being to say one part of the organism is classical and collapses the other part that’s quantum.
Another way materialists banish the quantum: the Many Worlds Hypothesis
Scientists have resolved the measurement problem another way. They hypothesize that instead of collapsing the quantum into the classical through observation, every time a quantum event collapses into a classical one, other universes are spawned. All the other probabilities that didn’t occur here does occur there, in these new universes.
This hypothesis is mathematically satisfying and sidesteps any suggestion of metaphysics. But there are a virtually infinite set of quantum events occurring everywhere at every instant everywhere in an organism, let alone the whole universe. Each of them would create an incalculable set of alternate universes. You do the dizzying math. Or alternatively, ask yourself: Which is the more ridiculous vision of the cosmos? This vision creates an even crazier and more incomprehensible cosmos than the one we have.
But who knows? That’s what they said about quantum theory in the twentieth century. And that’s what most well-educated, modern, rational sophisticated people say about God.
Quantum theology of matzah
Quantum theology is a term used by a few but growing number of theologians and mystics. Many of their essays and speculations are plagued by vagueness, weak understanding of science, and an over-heated, optimistic leap into the irrational analogies between quantum science and mysticism to prove God’s existence. Their “proofs” often require taking analogous-sounding mysteries as equivalents. Quantum theology is largely the provenance of well-educated fundamentalists.
The case of yeast is different. In this dance between the material and the vital, between science and faith, the science leads us to conclude something mystical is happening in bread that doesn’t occur in matzah. That matzah has been promising something like this is lurking in its layers of meaning is a deligthful coincidence. Even on its own terms, though, the new science of quantum biology shows quite specifically how the process of life itself depends on quantum action. In every possible process where life is created or sustained, enzymatic action is involved. And with quantum action comes the requirement that someone or something is observing the process. The nose of the quantum camel has entered the tent of biology, but it was summoned by the biology. In fact, the tent is the camel. Something or someone has to be observing omnipresent quantum events in enzymes to make them operative in life. Someone or something has to be operating life. Omnisciently.
Couple the biophysics with the metaphysics of the matzah and we get a powerful sermon. Matzah is bread without attention, perhaps without the attention of a Cosmic Consciousness. It represents enslavement to inert material. It is both literally the bread of affliction, the food of slaves, and symbolically life without redemption from our inner Egypt, the body without a soul. Matzah invokes a God who redeemed the Children of Israel from slavery more than three thousand years ago and Who continues to operate the universe today by attending to its every quantum event. He is an incomprehensibly vast God Who observes every infinitesimal event, all the infinite infinitesimal events that occur every instant to sustain each living cell of each living organism. This is a God that watches everything actively. This God expands and unfolds His Cognizance as much as the universe imagined by the Many Worlds Hypothesis multiplies infinitely bubbling alternatives, only this God gives it life and an elegant unity. I like this God and this idea of Him.
One of the sermons on matzah is a kabbalistic one. Isaac Luria, the 16th century mystic of Safed, explains that the three matzahs on the seder plate represent Knowledge, Understanding, and Wisdom. Matzah invites us to stretch our scientific wisdom to its fullest extent beyond enslavement to our preconceptions. Matzah also contains a sermon about the liberation of science from its prejudices.
 Prof. Judith Klinman of UC Berkeley first suggested that quantum processes were involved in the enzymatic action in 1987. She has more recently found experimental evidence for it. See, for instance, Judith P. Klinman and Amnon Kohen, “Hydrogen Tunneling Links Protein Dynamics to Enzyme Catalysis,” Annual Rev Biochem. 2013; 82: 471-496.