1924

Nobel Prize in Physics

Mapping the Atom, Decimal by Decimal

Manne Siegbahn

When Röntgen discovered X-rays in 1895, the obvious response was to point them at things and see what happened; what took rather longer was learning to use them as a precision instrument rather than a novelty. Manne Siegbahn, a Swedish physicist with a taste for meticulous engineering, spent the better part of two decades redesigning X-ray spectrometers until they could resolve the characteristic radiation emitted by individual elements with extraordinary accuracy — measuring the wavelengths to five or six significant figures, then adding another decimal place just because he could. Those measurements mapped the inner electron shells of atom after atom, supplying the hard numbers against which the emerging quantum theory of atomic structure could be tested and either trusted or discarded. The work was, in a sense, cartography: patient, unglamorous, and indispensable. Without it, the atom would have remained a theoretical convenience rather than a thing that could be measured; with it, spectroscopy became the language in which chemistry and physics eventually agreed to talk to each other.

Nobel Prize in Physiology or Medicine

A Fibre That Traced the Heartbeat

Willem Einthoven

For most of medical history, the doctor's assessment of the heart amounted to pressing an ear against a chest and listening for anything that sounded wrong — useful, but not exactly rigorous. Willem Einthoven, a Dutch physiologist, spent the 1890s trying to improve on the relatively crude galvanometers of his day and eventually constructed the string galvanometer: a device that suspended a thin silver-coated quartz fibre in a magnetic field, allowing the tiny electrical currents generated by each heartbeat to deflect it with measurable precision. By 1903 he was recording those deflections photographically, producing the first true electrocardiogram — with the P, Q, R, S, and T waves that cardiologists still name and read today. The equipment initially weighed around 270 kilograms and required five people to operate it, which imposed some practical limits on mobile diagnostics. In the decades that followed it shrank, spread, and became the first thing attached to almost anyone who arrives at a hospital in distress, a tracing on paper that tells a trained eye within seconds whether the heart is conducting normally, straining, or in the early stages of an infarction. A world without the ECG is one where a doctor can hear that something is wrong but cannot, without opening you up, say precisely what.

Nobel Prize in Literature

A Village, Told Through Its Seasons

Władysław Reymont

Władysław Reymont was a self-taught Polish novelist who had worked as a railway clerk, a wandering theatrical troupe member, and — following a train accident that left him temporarily bedridden — a writer with something urgent to say about the land. His four-volume cycle, Chłopi (The Peasants), follows a village in central Poland through an entire year, its chapters named for the seasons, its rhythms tied to the soil, the church calendar, and the raw social drama of who owns which strip of field. Published between 1904 and 1909, it drew on the naturalist tradition without quite belonging to it: the prose has a biblical, incantatory quality that sits oddly and beautifully beside the mud. The Nobel committee in 1924 cited his epic depiction of Polish peasant life, which was accurate, though slightly like praising the Iliad for its accurate depiction of Bronze Age military logistics. Reymont died the following year. The Peasants is the kind of novel that forms the bedrock of a national literature and gets described as 'essential reading' by everyone who has not yet read it; those who have tend to go rather quiet, which is perhaps more telling.

Edwin Hubble proves existence of other galaxies

A Smear of Light Turns Out to Be an Address

The Great Debate of 1920 had turned, partly, on a single question: was the Andromeda nebula a cloud of gas within the Milky Way, or an 'island universe' — an entire separate galaxy far beyond it? Harlow Shapley said it was near; Heber Curtis said it was distant and enormous. Edwin Hubble settled it. Using the 100-inch Hooker telescope at Mount Wilson, he identified Cepheid variable stars in Andromeda — stars whose brightness pulses on a known schedule, making them reliable distance markers — and calculated that they lay roughly 900,000 light-years away, far beyond the edge of any plausible Milky Way. He announced his findings in late 1924, and the implication was not subtle: the Milky Way, long assumed to be the full extent of creation, was one galaxy among many, perhaps countless. The universe had just grown by an amount that made 'large' seem like an inadequate word. Everything astronomers would go on to discover — expansion, dark matter, deep-field imaging of ten thousand galaxies in a patch of sky the size of a grain of sand held at arm's length — followed from the moment Hubble pointed his telescope at a smear of light and found it was an address.

Louis de Broglie submits doctoral thesis on matter waves

Every Particle Hums a Wavelength

Louis de Broglie was a French aristocrat who had trained as a historian before the First World War, worked as a military radio operator during it, and emerged with a deep interest in the physics of waves — which, in 1924, led him to a doctoral thesis of spectacular audacity. Since Einstein had shown in 1905 that light, long treated as a wave, also behaves as a particle, de Broglie asked the inverse: what if particles — electrons, protons, even billiard balls — also behave as waves? He proposed that any moving particle has an associated wavelength equal to Planck's constant divided by its momentum, a relation so clean it fit on a single line. His doctoral committee at the Sorbonne was, by most accounts, uncertain whether the idea was profound or eccentric, so they forwarded the thesis to Einstein, who replied that it looked illuminating. They awarded the degree. Three years later, Clinton Davisson and Lester Germer confirmed the prediction experimentally by diffracting electrons through a crystal lattice — watching particles make the wave patterns that only waves were supposed to make. De Broglie's wavelength now underlies electron microscopy, MRI, and the design of every semiconductor ever made, all resting on the peculiar fact that an electron does not entirely know whether it is a particle or a wave and has apparently decided not to choose.

Bose and Einstein publish quantum statistics papers

Particles That Cannot Be Told Apart

In 1924, Satyendra Nath Bose, a relatively unknown Indian physicist in Dhaka, wrote a short paper deriving Planck's black-body radiation law by treating photons as genuinely indistinguishable from one another — not just statistically exchangeable in the way that classical particles are, but fundamentally, ontologically identical, such that swapping two of them produces no new physical state. This was a quiet but radical departure from classical thinking, and the argument led to the right answer without invoking any of the classical assumptions that had always quietly propped up the derivation before. Bose sent the paper to Einstein, in English, with a note asking him to arrange publication if it seemed worthwhile. Einstein translated it into German, got it published, and then immediately extended the statistics to atoms, predicting that at sufficiently low temperatures a gas of such particles would all collapse into their lowest energy state — a fifth state of matter, now called a Bose-Einstein condensate, existing in a kind of quantum unison that defies every classical intuition about how matter should behave at low temperature. The condensate was not actually created in a laboratory until 1995, seventy-one years later, but when it was, it behaved precisely as Bose and Einstein had described: a small cloud of rubidium atoms, cooled to within a fraction of a degree of absolute zero, becoming for a brief moment a single quantum object that you could, in principle, see.

Hans Berger records the first electroencephalogram

The Brain Writes Its Own Record

Hans Berger had been trying, in his oblique and privately obsessed way, to detect the physical correlate of mental activity since the 1890s — driven partly by a strange conviction, rooted in a youthful near-accident, that the mind could communicate across distance by some electromagnetic means. The conviction was almost certainly wrong. The apparatus it motivated him to build was not. Working in Jena with a modified galvanometer and electrodes attached to the scalp, he recorded in 1924 the first recognisable electroencephalogram from a human subject — his teenage son Klaus — capturing the rhythmic electrical oscillations of the brain as a continuous ink trace on a moving paper strip. He identified what he called the alpha wave, a roughly ten-cycles-per-second rhythm prominent when a person is awake but relaxed, which changed character when the subject opened their eyes or performed mental arithmetic. Berger spent five years checking his results before publishing anything, convinced that the scientific establishment would dismiss him as a mystic, and was surprised to find that they largely agreed the recordings were real. The EEG became, and remains, the primary tool for diagnosing epilepsy, monitoring anaesthetic depth, and studying sleep — the brain, it turns out, writes its own record, provided someone bothers to listen for it.

Discovery of the Taung Child fossil

A Box Opened Before a Wedding

In 1924, a small fossilised skull arrived — blasted from a limestone quarry at Taung in what is now South Africa — on the desk of Raymond Dart, a young Australian-born anatomist at the University of the Witwatersrand. Dart was in the middle of getting dressed for a friend's wedding when the box was brought in; he opened it anyway. Inside was the cast of a brain unlike any ape's — larger, with a shape that suggested a more vertical face — and part of the skull and jaw of a juvenile who had died, he estimated, perhaps three million years ago. Dart named the creature Australopithecus africanus, placed it on the human lineage rather than the ape lineage, and argued in Nature that human evolution had begun in Africa, not Asia, where most of his colleagues expected to find its origins. Most of those colleagues disagreed emphatically, preferring the theory anchored in Asia — and, rather inconveniently, in the Piltdown Man, which had not yet been exposed as a fraud. It took decades, and more African fossils, for the scientific consensus to shift. Dart was eventually vindicated completely: Africa is now the undisputed cradle of hominid evolution, a conclusion that traces its documentary origin to a box opened in Johannesburg while a wedding party waited downstairs.

John Logie Baird transmits television images

A Maltese Cross, Sent Through the Air

In early 1924, John Logie Baird was working in a rented attic room in Soho with materials that would not have impressed anyone: a tea chest for a frame, a biscuit tin for a lens mount, a motor from an electric fan, lengths of wire, and a rather ingenious desperation. He had been chasing the idea of electrically transmitting moving pictures for years, through failed businesses and genuinely precarious health, and he was operating on almost no money in conditions that would not have met any reasonable safety standard. His first successful transmission of a recognisable image — a Maltese cross, blurred and flickering across a few feet of air — was nonetheless a transmission: the image left one place and arrived, electronically, at another. Baird would go on to demonstrate the technology publicly at the Royal Institution in 1926 and eventually, improbably, win a contract with the BBC. The image quality started poor and improved slowly. What never quite improved was anyone's certainty that television, as a medium, had been entirely good news for civilisation — though one suspects Baird, who had simply wanted to solve an engineering problem, would have found that observation somewhat beside the point.