Worth it in part

A sharp tip on a bending cantilever, tracked by a laser, let researchers feel the shape of a surface at nanometre scale, including surfaces that do not conduct electricity at all.

René Thom classified every possible way a stable system can suddenly break into seven geometric templates. The mathematics is settled; its 1970s use to explain animal and human behaviour was not, and a public critique said so.

A single earthquake can be read as a diagram that looks like a beach ball. Which quadrants come out shaded tells you whether a fault pulled apart, pushed together or slid sideways — and that reading once settled a live argument about seafloor spreading.

Shine light on a surface and the electrons it knocks loose carry a precise record of the energy levels inside — the method Kai Siegbahn spent decades turning into one of chemistry's sharpest tools.

To make his 1900 blackbody radiation law work, Max Planck assumed energy could only be emitted in fixed units, a device he called a formal assumption and did not believe was physically real.

Plants have no glands and no circulatory system, yet every cell can make its own hormones, and this brief follows how at least nine separate signal classes coordinate growth without either of those animal-style tools.

Ordinary oxygen is attracted to a magnet, a fact the older theory of chemical bonds simply could not explain. Molecular orbital theory got it right by giving up on the idea that a bond belongs to two atoms alone.

On 20 May 2019 the kilogram stopped being a chunk of metal in France and became a consequence of the Planck constant. The vote took eleven years to arrive and left a few loose mathematical ends behind.

Signal detection theory, formalised in 1954 out of radar research and set out for psychology by Green and Swets in 1966, split a single accuracy score into two things: how well someone can actually tell signal from noise, and how readily they say yes at all.

In 1954 Bell Labs built a silicon cell that converted sunlight to electricity roughly six times better than anything before it, and then spent the next two decades discovering that solving efficiency was the easy half of the problem.

Frederick Hopkins didn't discover a vitamin; he proved by feeding trial that food contains something beyond protein, fat and carbohydrate that animals cannot grow without.

A phenomenon first noticed in 1801, that an electric field drags charged particles through a fluid, took more than a century of small, separate refinements before it became the gel-based technique that now sorts DNA and proteins by size in nearly every biology lab.

In 1975 researchers identified enkephalin, a chain of just five amino acids made in the brain, as a substance the body produces on its own that binds the very receptors morphine does — the first sign of a whole family of the body's own pain and reward chemistry.

Thallium would rather give up one electron than the three its position on the periodic table suggests it should. Sidgwick named the pattern in 1927; nobody has ever reduced it to a single cause.

Trillions of microbes live on and in every human body, and genetic sequencing has replaced old guesses about their numbers and roles — but most links between the microbiome and disease remain correlations, not proven causes.

The metre, the kilogram and five other units used to rest on physical objects kept in a French vault. Now every one of them is fixed to a constant of nature, and the change is quieter than it sounds.

Honey and jam are supposed to be too dry inside for anything to grow, yet certain fungi manage it anyway, and this brief follows the specific chemistry that lets xerophiles colonise exactly the low-water conditions food preservation depends on.