Optogenetics, neutrino astronomy and mirror-image chemistry share more than a prize year. Light, decades of patience and curiosity-driven research link all three.
Nobel Prizes are awarded field by field, and the fields rarely talk to each other. A neuroscientist has little reason to follow neutrino astronomy; a physicist seldom reads about catalysts. This year, though, the three science prizes have so much in common that they are worth reading as one story.
Seeing what could not be seen
Start with what each prize made visible. Before optogenetics, the role of a single type of neuron inside a living brain could only be inferred; now it can be tested by switching that neuron on or off. Before IceCube, the sources of the universe’s most energetic particles were hidden behind dust, gas and magnetic fields; now some of them have been located through the neutrinos they emit. Before Kagan and Soai, the idea that molecular handedness could arise and amplify itself without help was a theory; now it can be watched in a flask.
In each case, the breakthrough was less a new fact than a new way of looking. That is why these prizes will keep paying off. A fact answers one question. A method answers thousands, including ones nobody has thought to ask yet.
Light as the common thread
The second link is physical: all three run on light.
In optogenetics, a flash of blue light opens channelrhodopsin, the algal protein at the heart of the method, and makes a neuron fire. In IceCube, the signal is also blue: the faint Cherenkov light given off when a particle produced by a neutrino races through ice faster than light itself can travel in that medium. And molecular handedness was first noticed through light. In the early nineteenth century, Jean-Baptiste Biot saw that certain substances rotate the plane of polarised light. In 1848 Louis Pasteur traced that rotation to mirror-image crystals and, through them, to mirror-image molecules.
Light is the oldest scientific instrument there is. This year’s prizes show it still doing new work: as a switch, as a messenger and as a probe of shape.
The patience of basic science
The third link is time. None of these achievements was quick, and none was planned with its eventual use in mind.
Peter Hegemann spent years studying how a single-celled alga senses light, a question with no obvious application. The channelrhodopsin papers came in 2002 and 2003; the first demonstration in neurons followed in 2005; the Nobel came this year. Francis Halzen proposed using Antarctic ice as a neutrino detector in 1988. The finished detector was completed in 2010, its first cosmic neutrinos reported in 2013. Henri Kagan’s non-linear effect dates from 1986. He was 95 when the prize was announced.
In each case, the work began as a question asked for its own sake: how does an alga find the sun, where do cosmic rays come from, why does a catalyst behave unexpectedly? The applications, from mapping brain circuits to designing drug-making reactions, came later and often from other people.
This is the familiar argument for curiosity-driven research, and these prizes make it with unusual force. A funding committee in the 1990s, asked to choose between “algal phototaxis” and a project with a clear medical goal, might well have picked the second. It would have missed one of the most important tools in modern neuroscience.
Instruments, engineering and teamwork
The fourth link is easy to overlook: each prize depended as much on engineering as on insight. Optogenetics needed viruses to deliver genes, optical fibres to carry light into the brain, and fast light sources. IceCube needed hot-water drills that could work at the South Pole, sensors that could survive decades in ice, and data systems that could sift a few cosmic signals from a flood of background. Chirality research depends on instruments that can measure how pure a sample is, down to fractions of a per cent.
And each was a collaboration, often across borders. Two German biophysicists worked alongside an American psychiatrist and bioengineer. A Belgian-born theorist led an international team at a United States university. French and Japanese chemists built on each other’s work across decades.
What India can take from this
India is part of these stories in small but real ways. A laboratory in Hyderabad has collaborated for years with Hegemann on using light-activated tools in parasites. Indian physicists work within the IceCube collaboration and analyse its public data. India’s pharmaceutical industry depends on chiral chemistry every day.
The prizes also suggest some lessons. Long-horizon funding matters; the Anusandhan National Research Foundation, created to strengthen research funding, will be judged partly on whether it backs questions without obvious payoffs. The ability to build and maintain instruments matters as much as the ability to use them. Large projects need sustained commitment, as the long delays to India’s own neutrino observatory show. And open data allows researchers far from the big detectors to do frontier science.
None of these lessons is new. This year’s Nobel Prizes simply show them working, in three very different laboratories, all of them in the end looking through light.
– Nishtala V Subrahmanyam
