Taming the Unseen

The Physics Nobel for three pioneering Berkeley physicists this year marks a watershed moment for quantum mechanics.

John Clarke, Michel Devoret and John Martinis

Earlier this week, the Royal Swedish Academy of Sciences presented the field of quantum mechanics with a fitting centennial gift: the 2025 Nobel Prize in Physics, which went to physicists John Clarke, Michel Devoret and John Martinis for their work done four decades ago at the University of California, Berkeley.

The trio have redefined what quantum physics could mean. Their work showed that the spooky, counterintuitive laws governing the atomic world could be coaxed into appearing at human scales, bridging a divide that had existed since the birth of the discipline itself. It echoed debates and problems chronicled in classic texts such as Max Born’s ‘Atomic Physics’ (English translation pub. 1935) and Werner Heisenberg’s ‘The Physical Principles of the Quantum Theory’ (1930).

Quantum mechanics, forged in the intellectual ferment of the 1920s by pioneers such as Niels Bohr, Werner Heisenberg, and Erwin Schrödinger, has long unsettled even its greatest minds.

In 1926, Albert Einstein famously wrote: “The theory [quantum mechanics] produces a good deal but hardly brings us closer to the secret of the Old One. I am at all events convinced that He [meaning God] does not play dice.” Einstein was responding to Max Born, who had argued that the heart of the new theory beats randomly and uncertainly, as if suffering from arrhythmia. Whereas classical physics promised that push here yields a predictable outcome there, quantum mechanics suggested that even under identical conditions, the same action could produce a range of results, each with a calculable probability and sometimes outcomes that seemed entirely contrary. Einstein’s objection was not to the mathematical formalism itself, which worked brilliantly, but to the probabilistic interpretation that suggested nature at its core was inherently uncertain.

In the quantum realm, particles exist not in fixed positions but as clouds of probability; they can appear to tunnel through barriers they have no right to cross. It is a world in which determinism dissolves, to be replaced by shimmering uncertainty. For decades, this bizarre behaviour was thought to belong exclusively to the infinitesimal (electrons, photons, and atoms) and never to the tangible world of wires and circuits (something that was explored in Richard Feynman’s celebrated lectures on physics in the 1960s).

Clarke, Devoret and Martinis upended that assumption. In the early 1980s, at the University of California, Berkeley, they took inspiration from the tools of low-temperature physics and turned it to a new purpose: showing that the quantum could be engineered.

Working with ultracold superconducting circuits, they demonstrated that vast swarms of electrons could collectively display ‘quantum tunnelling.’ The circuits, visible to the naked eye, behaved like giant quantum particles, a revelation that suggested quantum mechanics was not a special rulebook for the microscopic but a universal language that, under the right conditions, governed everything.

By taming that chaos, the Berkeley trio blurred a boundary that had seemed immovable since the days of Bohr’s Copenhagen debates.

The implications were profound. Their findings virtually birthed ‘quantum electrical engineering’ - a discipline that transformed quantum mechanics from philosophical curiosity into practical craft. Circuits inspired by the trio’s experiments are now used to simulate atoms, detect faint particles, and serve as qubits, the building blocks of quantum computers.

That last application, curiously, went largely unmentioned in this year’s Nobel citation. Yet it is impossible to ignore. Without the pioneering work at Berkeley, the race now underway between Google, IBM, and Chinese labs to build a fault-tolerant quantum computer would have remained a fantasy. John Martinis himself would later lead Google’s quantum supremacy experiment in 2019, when a superconducting circuit performed a calculation no classical supercomputer could manage in a feasible time. The roots of that triumph trace directly back to the trio’s early insight: that quantum effects could be scaled up, controlled and harnessed - an insight foreshadowed in foundational studies like British-American theoretical physicist Anthony Leggett’s seminal ‘Macroscopic Quantum Systems’ (1980).

Leggett’s theoretical framework laid the groundwork for understanding phenomena such as superconducting circuits, which Clarke, Devoret and Martinis would later manipulate in the laboratory to make quantum effects tangible and measurable.

Quantum theory has always been as much a philosophical challenge as a scientific one. Its discovery in the early 20th century forced physicists to abandon the certainties of Newtonian order. The 2025 Nobel Prize celebrates the moment where quantum mechanics, once the physics of the invisible, has finally become the physics of possibility.