Tag: science

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Bread California San Francisco/California

Larraburu

There were three sourdough breads in San Francisco and they were not the same thing. Boudin was at Fisherman’s Wharf, which told you everything. Parisian was on the better grocery shelves and at the airport, which told you the rest. Larraburu was in the neighborhood, which is to say it was not selling anything except bread.

I was living in Daly City when I found them. I was seventeen, or eighteen, which is the age when you begin to understand that the thing everyone points to is rarely the thing worth finding. I had eaten Boudin at the wharf, standing in the fog with everyone else who had just arrived somewhere. It was fine. It was what people meant when they said sourdough. Parisian was more serious, or wanted to be — the bread you bought at the airport to prove you’d really been here, to carry the city home in a bag. But there was something in both of them that felt like a performance, and I was at the age when performance was exactly what I was trying to see through.

Larraburu didn’t perform. The crust was softer than it had any right to be. The sour was there but it didn’t insist on itself. You tasted wheat and time and something faintly cool and creamy underneath. It was bread that assumed you already knew what you were doing.

They closed in 1976. Parisian lasted until 2007. Boudin is still on the wharf.

I have thought about this more than is strictly reasonable. What I keep coming back to is not the taste exactly, though the taste is there when I reach for it. What I keep coming back to is the distinction itself — the fact that I made it, that it mattered to me, that I was nineteen years old in Berkeley and buying bread from a neighborhood bakery in San Francisco because I had decided it was the real thing. You make these small declarations about who you are. Most of them dissolve. Some of them stay.

The two brothers who started Larraburu came from the Basque country in 1896 and brought their starter with them. By the time I was eating their bread the starter was already older than the state of California. They fed it three times a day, every day, for eighty years. That kind of commitment doesn’t announce itself. It just shows up in the bread.

In 1969 scientists from the United States Department of Agriculture began studying sourdough cultures from five San Francisco bakeries. They were trying to understand what made the bread taste the way it did, why you could not replicate it elsewhere, why bakers who moved away and took their starters with them found the flavor slowly changing, the sourness shifting, something essential escaping. They worked for years before a team at Oregon State University finally isolated what they were looking for — a previously unknown bacterium living inside the wild yeast, producing the lactic acid that gave the bread its character. They named it Lactobacillus sanfranciscensis. One of the five bakeries in the study was Larraburu.

The starter the brothers brought from the Basque country in 1896 was not simply old. It was a living record of every bakery it had passed through, every hand that had fed it, every climate it had survived. A sourdough starter is not a recipe. It is a culture in the biological sense — a community of organisms with a history, shaped by everything that has ever happened to it. You can write down the formula. You cannot write down what the starter knows.

Larraburu baked twenty-four hours a day. The sponge was rebuilt every eight hours, three times daily, without interruption. Two parts previous sponge, two parts high-gluten flour, one part water. Hold seven to eight hours. Rebuild. The rhythm was closer to farming than to cooking — less a process than a relationship, sustained across decades, across generations, across an ocean.

What I know now that I didn’t know then is that the starter survived the bakery. Someone saved a piece of it when they closed. It traveled to Hawaii, sat in a refrigerator on Maui, kept being fed. A culture that old doesn’t care about bankruptcy or lawsuits or whether the ovens are still running. It just wants flour and water and time.

I find something in that. Not consolation exactly. More like confirmation of something I already believed at seventeen, standing in the fog, learning to tell the difference.

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Technology

The Silence of Glass

There is a moment, right before surgery, when the anesthesiologist asks you to count backward from ten. You get to seven, maybe six, and then the world goes clean and white. Scientists have a word for the material responsible for that transition: borosilicate. The same compound in the syringe barrel is in the telescope mirror trained on the Andromeda galaxy, in the fiber strand carrying the surgeon’s consultation with a colleague three thousand miles away, in the smartphone screen the patient’s wife is staring at in the waiting room, hands shaking, refreshing nothing.

Glass is everywhere and we have made it invisible, which is the oldest trick civilization knows.

Vaclav Smil argues in Making the Modern World that the most consequential material of the last two centuries is not steel or silicon or oil. It is float glass — invented by Alastair Pilkington in 1959, when he watched dishwater spread across his kitchen sink and understood something that had eluded glassmakers for four hundred years. Pour molten glass onto a bath of molten tin and it finds its own level. It becomes, on its own, perfectly flat. Every window, phone screen, solar panel, and architectural facade descends from a man watching his wife do dishes.

What Smil doesn’t quite say — though you feel it accumulating across his pages — is that glass is the one material that consistently mediates between the inner and the outer. Not metaphorically. Literally. It stands at the boundary and says: you may look, but you may not touch.

The fiber optic cable looks like nothing. Pull back the orange jacket and you find strands thinner than a human hair, each one pure silica glass so precisely drawn that a photon launched into one end will emerge after sixty miles having lost less than five percent of its energy. That number seems impossible. It is a kind of miracle achieved through obsessive purity: any contaminant at the molecular level, any stress in the crystal lattice, any deviation in the core diameter, and the light scatters and dies. Underneath every ocean, through every mountain, connecting data centers in Virginia to servers in Singapore, there are hundreds of millions of kilometers of this material, laid in darkness, carrying light.

I think about that sometimes when I hit send. The electrons leave my keyboard, convert to photons at some local junction, and then travel — genuinely travel, as light through glass — to wherever they are going. There is something devotional about it, though I can’t quite say why. Maybe it’s the invisibility. Maybe it’s the faith required — that the thing you release will arrive, intact, somewhere it has never been.

Glass is in the MRI machine and the X-ray plate and the laboratory flask where the drug was first synthesized and the vial where it is stored and the syringe through which it enters the body. Glass does not react. It does not corrode. It does not leach. This chemical inertness, which seems like absence, is actually the whole point. Medicine needed a container that would hold the thing without becoming it.

There is also glass in the eye reading the label on that vial. The human lens is, optically speaking, a soft glass. It focuses, ages, clouds — cataracts are the eye’s glass going milky — and the surgeon replaces it with an intraocular lens engineered to behave like glass. We have spent considerable effort making fake versions of something the body was already doing.

For most of human history, clear glass was expensive, fragile, and small. Window glass in medieval Europe admitted light hazily, like looking through ice. Clear vision was for churches, which is perhaps why we came to associate light with the sacred — it literally arrived, in those buildings, in a way it did not arrive anywhere else. Then Pilkington’s tin bath made clarity cheap, and the world changed in ways nobody fully catalogued because the change was so pervasive: big windows, watched experiments, extended growing seasons, telescopes reaching farther, microscopes going smaller. Each a story of glass making a distance crossable that was not crossable before.

The screen I am writing this on is glass. The Corning Gorilla Glass on this display is an alkali-aluminosilicate sheet, chemically strengthened through ion exchange, harder than most knives, clear enough that the pixels look like they are sitting on the surface rather than behind it. Apple spends considerable engineering effort making the glass seem like it isn’t there. The ideal phone screen is invisible. A window to computation.

And yet the glass is the thing you actually touch. All day. More than you touch almost anyone. The glass is warm from your hands. It has learned, in a way, the pressure of your thumbs.

Glass is the material of thresholds — it makes the threshold visible, makes it possible to stand at a door and see all the way through before you decide whether to enter. We built the internet through it. We see our loved ones through it. We study cancer through it. We watch the news through glass that traveled to us through glass captured by cameras with glass sensors launched on satellites with glass lenses through a sky that is itself, technically, a lens — bending and filtering the light from everything that has ever been.

In the hospital waiting room, the wife is still holding her phone. The screen has gone dark. She taps it. It lights up. She looks at her own reflection for a moment — the screen a mirror now — before the notification arrives and the glass goes transparent again, the way it always does, showing her something other than herself.

That is what glass does. It waits. It holds. And then, when there is something to show, it gets out of the way.

Categories
Science Stanford

Bypassing the Leaf

For my entire life, I’ve understood the world through a simple, quiet equation: green plants take sunlight and air, and turn them into the stuff of life. It is a slow, terrestrial magic we all learn in grade school.

But lately, after listening to Professor Drew Endy at Stanford, I’ve been sitting with a curious yet exciting realization: that ancient equation is being rewritten.

Professor Endy champions a concept called electrobiosynthesis, or eBio. At its core, it represents the engineering of a parallel carbon cycle that operates independently of traditional photosynthesis.

The global industrial complex is approaching a transition point where our traditional reliance on extractive fossil fuels is being superseded by a regenerative, biological manufacturing paradigm.

For millennia, humanity has relied on the biological “middleman” of the plant to capture solar energy. But natural photosynthesis, for all its quiet beauty, is limited by severe biochemical constraints. Most commercial crops convert less than 1% of incident solar energy into usable biomass.

Electrobiosynthesis changes the math. By bypassing the plant entirely, we can utilize high-efficiency photovoltaics—which capture over 20% of the sun’s energy—to drive carbon fixation directly into the metabolic hubs of engineered microbes. This fixed carbon is transformed into organic molecules, serving as the feedstocks for high-value products like proteins and specialty chemicals.

In my own career, I’ve watched industries undergo profound, structural phase shifts. This really feels like another one of them. It seems that we are looking at a future where any molecule that can be encoded in DNA can be grown locally and on-demand. This fundamentally decouples manufacturing from centralized industrial nodes and fragile global supply chains.

The field appears to currently be in its “transistor moment,” moving from laboratory feasibility to industrial pilot plants. It signifies the ability to construct and sustain life-like processes without being restricted to the terrestrial lineage of photosynthesis.

Of course, with such foundational power comes the weight of unintended consequences. The ability to engineer life at this level brings severe biosecurity risks, and even the “Sputnik-like” strategic challenge of international competition in biotechnology. There are profound ethical dilemmas on the horizon, such as the creation of “mirror life”—organisms made from mirror-image biomolecules that might be invisible to natural ecosystems.

But the trajectory seems set. The vision described by Professor Endy—a world where we grow what we need, wherever we are, using only air and electricity—is no longer a distant science fiction. It is a nascent industrial reality. This future is being written not in sprawling factories, but in the microscopic architecture of the cell.

I’ve just now reading a deep research report on this whole area that I asked Google Gemini to create. It’s fascinating and I’ve discovered a whole new area (beyond AI) to explore further.

Categories
Atomic Energy Nuclear Energy Science

The Traffic Light That Split the Atom

If you wandered past the Mathematical Society and kept going, you’d come to a pedestrian crossing on Southampton Row where it meets Russell Square in London’s Bloomsbury. On a humid morning in September 1933, something world-changing happened there.

It was Tuesday, September 12. A cool, drizzling, quintessentially English autumn day. Leo Szilard — a brilliant, restless Hungarian-Jewish physicist who had fled Nazi Germany earlier that year — stood waiting at the traffic light. He was irritated, as people often are when a red light holds them up on a gray morning. He had been thinking about Ernest Rutherford’s recent lecture, in which the great pioneer of nuclear physics had dismissed the idea of extracting usable energy from the atom as “moonshine.”

Szilard disagreed. And as the light turned green and he stepped off the curb, the thought arrived in a flash.

What if a single neutron struck a nucleus and caused it to split, releasing two neutrons? Those two could split two more nuclei, releasing four — then eight, sixteen, thirty-two. In a large enough mass of the right material, the process could sustain itself — a chain reaction — and liberate enormous amounts of energy.

He saw it all in that instant: the possibility of limitless power, and the shadow of a weapon unlike anything the world had ever known.

Szilard was not in a laboratory. He was not surrounded by colleagues or equipment. He was simply crossing a London street, a refugee with too much on his mind, when the future opened up in front of him.

He filed a patent within the year and had it kept secret by the British Admiralty. He spent the rest of his life in the aftermath of that crossing — working on the first controlled chain reaction in Chicago in 1942, then becoming one of the most tireless advocates against the use of the weapons he had foreseen. The man who imagined the chain reaction spent decades trying to break it.

The spot where it happened remains utterly ordinary. Buses and taxis still rumble through the intersection. Tourists hurry toward the British Museum. Students cross on their way to Russell Square. There is no plaque. Szilard himself, given how deeply pacifist he became, might not have wanted one.

That feels right. The moment wasn’t grand or ceremonial. It was the kind of quiet, internal shift that happens when a prepared mind meets an ordinary irritation at a traffic light.

The hinges of history are fragile things, and they don’t announce themselves. Enormous consequences — nuclear power, the atomic bomb, the Cold War, decades of arms-control efforts — all trace back to one man’s realization while crossing a rainy London street. And once a thought like that arrives, it doesn’t leave. Szilard carried his for the rest of his life. He understood, earlier than almost anyone, both the dazzling promise and the terrible cost of what he had imagined at that crossing.

I came to this story through Sebastian Mallaby’s The Infinity Machine. It stopped me cold on the page, the way the best historical details do — not because it was dramatic, but because it was so ordinary.

Next time you’re stuck at a pedestrian light on a humid morning, pause for a moment. The light will change. You’ll step forward. But you never really know what might change with you.