Author’s note: This article discusses, in large part, cutting-edge science which I am not qualified to explain in any technical sense. These discoveries were the culminations of entire scientific careers and as such, are far beyond the scope of a journalistic article such as this. If you wish to read further on any of the discussed topics, see the bibliography below.
NB: Nobel Prizes are often awarded for work that can be up to several decades old.
Their work with the material (a one layer thick sheet of carbon atoms, each with one delocalised electron as a result of their forming only 3 out of a possible 4 bonds) helped to determine its properties as a potential “super-material” to be used in all forms of electronics. It is the thinnest known material, but is also the strongest in spite of this. It is as good a conductor of electricity as copper and it is the best known conductor of heat. All these amazing properties, and yet it can be produced from graphite with regular sticky tape!
This discovery was a momentous occasion in the world of physics. It gave more credence to idea of a “big bang” and led on to the concept of “dark energy”. This “dark energy” is said to be responsible for the acceleration of the universe’s rate of expansion. The discovery is based on ‘line spectra’. When non-metal elements are heated, they emit light of particular frequencies: combining this phenomenon with our observation of distant stars/galaxies, we see an overall shift towards the red and of the spectrum. This red-shifting showed even greater shifts when observed supernovae were further away from us: this implied that they were actually accelerating away from us. Perhaps the most significant aspect of this discovery was that it ended up proving Einstein’s cosmological constant – by his reckoning, “the biggest blunder” of his scientific career – to be correct.
Whilst the two laureates‘ methods (which were developed independently of one another) were based on similar principles, they both offered diametrically opposed approaches to monitoring quantum systems. The need for these methods is primarily due to issues involving how observation of a system can change its behaviour: these methods allow for the isolation of individual quantum particles such as photons and the subsequent observation of their behaviour without this issue’s occurrence. Essentially, the ‘observation’ of quantum states removes many of their properties, most of all the ‘superpositions’ that are common in quantum systems are lost upon direct observation. These methods finally allowed us to isolate quantum particles without this unfortunate side-effect.
2013: Awarded to François Englert and Peter W. Higgs
“for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN’s Large Hadron Collider”
Englert and his late colleague Robert Brout proposed the theory of the so-called ‘Higgs’ field and ‘Higgs’ boson independently from Peter Higgs (Higgs published his paper first, hence the naming after him). Their theories collectively explained how mass arose under the Standard Model: our previous understanding suggested that no force particles could have mass. Especially given that our understanding of gauge bosons (force carriers for the four fundamental forces) was that they required unbroken gauge symmetry, the phenomenon of mass was strange under this model. Gauge symmetry was thought to apply to all gauge bosons and its nature prevented the force carriers from gaining a mass. This was confusing, given the observations of the W boson and the Z boson, (the particles associated with the weak nuclear force) which behaved as though they had mass. The idea of simply giving these particles mass was disproven as it would either result in predictions that tend to infinity, or it would require another massless particle as a mediator which was disproven through observation. This led to the radical idea of endowing empty space with energy: on interaction with the Higgs field, gauge bosons “lose” kinetic energy, which is converted into mass energy, potentially to become the fabled Higgs Boson (Note that this description is a loose analogy: the Higgs field is not a drag and does not technically “slow” otherwise light-speed particles. In reality, the mechanism actually results in continued interactions with the Higgs field, which change the direction of a particle: since the Higgs field exists everywhere, that means the particle is constantly changing direction and will, on the whole, no longer move at the speed of light). In reference to the gauge symmetry or rather gauge invariance which the Higgs interactions ‘break’, this interaction is also sometimes referred to as the “spontaneous breaking” of the gauge symmetry. The prize was awarded shortly after observations by two teams at CERN confirmed the particle’s existence.
The blue LED was the last piece of the puzzle to try and create white LEDs (the three primary colours red green and blue being needed to achieve a white colour). However, any methods of creating blue LEDs eluded the scientific community. LEDs are much longer-lasting and more energy efficient than alternative light sources. Generally, previous methods relied on heating metal filaments such as tungsten to emit white light. However, LEDs require much less energy to be input: LEDs emit light when the semiconductors (of which they are composed) have an electrical current passed through them. The wavelength (colour) of this light is determined by the band gap (space between electron shells) of the materials. This discovery marked the first successful attempt to generate blue and subsequently, white light.
Neutrinos are the second most abundant particles in the universe behind photons, and yet they remain among the most enigmatic to us. The ghostly particles rarely interact with regular matter and furthermore are “left-handed” particles (this refers to the direction of their spin – spin being a fundamental type of angular momentum in subatomic particles). This “left-handedness” means that they likely cannot interact with the Higgs field: their mass is coming from elsewhere (the origin is still unknown). Even more puzzling was the fact that our detectors seemingly failed to detect a vast majority of the expected neutrino emissions from different sources. The prize recognises the observations that neutrinos can oscillate between their three “flavours” (yes that is the term for the different types of neutrino). This observation confirmed that neutrinos had mass, albeit they still had no defined mass: their mass is, under current theories, described as a superposition (probability) of masses. This therefore allows for the oscillations between flavours, as neutrinos are not bound to any mass, they are instead merely likely to be of a certain mass.
Yet another interesting example of how seemingly obscure maths concepts apply to modern physics, the so-called ‘topological phases’ of matter were initially used to counter the previous theory that superconductivity and suprafluidity could not occur in thin layers. They have since also gone on to explain conductance as being topological and explaining the properties of the small magnets that can be found in certain materials. We now know of several more topological phases, including those found in some 3D structures. Research into this area is currently a prominent front, owing to the fact that these structures show promise that they might be useful in electronics.
The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a collaboration of over a thousand scientists from more than 20 countries. Their efforts have realised the observation of gravitational waves, a phenomenon Einstein predicted over 100 years ago. However, he believed that we would never be able to detect them. This monumental discovery disproved that hypothesis: By utilising a laser-based interferometer to eliminate background noise Thorne and Weiss were firmly convinced they could detect gravitational waves. Along with the help of Barish, the project leader, they brought their contraption to fruition, and using their interferometer, they measured the gravitational waves emitted by the collision of two black holes; this change was smaller than the size of a nucleus, but it provided yet another testimony to the credence of Einstein’s relativity.
2018: Awarded “for groundbreaking inventions in the field of laser physics” Arthur Ashkin “for the optical tweezers and their application to biological systems”
Gérard Mourou and Donna Strickland “for their method of generating high-intensity, ultra-short optical pulses”
Ashkin’s share of the prize owes to his invention of optical tweezers: utilising two laser beams, he could ‘grab’ objects. Owing to the radiation pressure of light (the exchange of momentum between particles and the electromagnetic (EM) field), he could even capture living bacterial cells without harming them.
Mourou and Strickland’s share owes to their development of techniques to produce high-intensity, ultra-short laser pulses. Taking advantage of the effects of time dilation, they stretched the laser beams in time to amplify them, later recompressing them which resulted in far higher intensities and far shorter pulses. This technique called chirped pulse amplification (CPA) has become the standard for high-intensity lasers. It’s many applications include, most notably, the millions of laser eye surgeries conducted worldwide every year.
2019: Awarded “for contributions to our understanding of the evolution of the universe and Earth’s place in the cosmos””
James Peebles “for theoretical discoveries in physical cosmology”
Michel Mayor and Didier Queloz “for the discovery of an exoplanet orbiting a solar-type star”
Peebles’ contributions to the Big Bang model are invaluable to our understanding of the universe. His calculations were ably tracing back the leftover radiation from the early universe to its origin. This model, however, presented one large problem: the ‘regular’ matter which we observe constitutes only 5% of all matter, with the other 95% consisting of dark matter and dark energy. The origin and properties of dark matter/energy is one of the biggest problems faced by modern physics and was in fact also a problem that Peebles himself contributed to in its early stages. Peebles was always at the forefront of his field, making contributions to fields that would soon become key areas of interest for researchers worldwide: he predicted Cosmic Microwave Background Radiation (CMBR) before it was detected, and worked extensively on structure formation in the (early) universe well before it became a serious cause for concern. His share of the prize recognises these accomplishments, which rank among his greatest achievements throughout his scientific career.
Mayor and Queloz’s share of the prize recognises their discovery of the exoplanet 51 Pegasi b: this was the first planet outside our solar system every to be discovered and it sparked a new age of astronomy. Since the discovery of 51 Pegasi b, over 4000 other exoplanets have been located throughout the Milky Way. The reason it was such a momentous task to detect an exoplanet is of course that planets don’t glow: they merely weakly reflect some of the light from their star. This light, however, is completely outshone by that of the start at any distance between solar systems. Instead, they utilise a method based on radial velocity: this method deduces the presence of exoplanets based on their impacts on their stars’ movements. By taking into account these factors, this method has isolated countless exoplanets since this, its first successful use.
Their work with these complex carbon-metal structures became an element of the foundation of organic chemistry, which itself allows us ascertain properties of life and how it came about. Previous methods of observing carbon chemistry were ineffective at producing complex molecules. Carbon compounds are largely stable and unreactive: this meant precious methods had to try and increase the reactivity of these compounds. However they produced many by-products when trying to produce more complex molecules: this cross coupling method completely subverts this problem. It is now used widely in research involving organic chemistry.
2011: Awarded to Dan Shechtman
“for the discovery of quasicrystals”
This was the first physical discovery of a well-established type of compound in principle: defined as being mathematically regular structures which do not follow periodically repeating structures. The incredibly versatile compounds have since been found to have applications in electronics, engines, and as general-purpose materials, particularly as coatings for existing materials.
The research into the inner workings of these receptors is of significant importance to organic chemistry. It is of particular significance to our understanding of how cells ‘sense’ their environment. The family of receptors that this research centred around is responsible for the detection of many important hormones such as adrenaline. This culminated in 2011, when Kobilka’s team was able to image the β-adrenergic receptor at the moment to received a hormone and relayed the information to the cell.
Theoretical chemistry had long been playing second fiddle to practical chemistry, but neither were ever able to accurately describe complex reactions, they were especially unable to describe what happened during a chemical reaction. The theoretical chemists could simulate reactions accurately by employing the laws of quantum physics, however this is very processor intensive and is simply infeasible with more complex reactions: we don’t have the computer resources. The experimentalists, on the other hand, could observe the results, but the process – which could be over in as little as a millisecond – could not be accurately measured. This prize recognises the achievement of ‘unifying’ classical physics with quantum physics when simulating reactions, thus solving the problem of computer resources being unable to cope. For the first time, it put theorists on par with experimental.
Traditional microscopy was postulated to have a limit of its resolution at around 0.2 micrometers: clearly that was problematic for the study of chemistry, when chemists often consider distances as small as the nanometre scale. Stefan Hell’s share of the prize recognises his work on stimulated emission depletion (STED) microscopy. In this methods, two lasers are used to simultaneously stimulate fluorescence in the desired molecules whilst negating any interfering fluorescence. Betzig and Moerner’s shares are in recognition of their method, called single-molecule microscopy. This method is based on the principle that the fluorescence of a molecule can be toggled: therefore, following the repeated imaging of small sections of the molecule, the images are superimposed on each other to reveal a detailed image.
In the past, it was believed that DNA was an extremely stable molecule. However, this is not the case at all; DNA is inherently unstable. Even if it weren’t it is constantly being damaged by UV rays and errors during duplication: for life to have developed, there clearly had to have been some method of DNA repair. As it turns out, there are several ways in which DNA’s integrity is maintained and each of the laureates discovered a different mechanism. Lindahl discovered the first mechanism, base excision repair, which counteracts the natural decay of our DNA. Sancar discovered the second, nucleotide excision repair, which repairs damage done by UV rays and other mutagens. Modrich discovered the thrid, mismatch repair, which reduces the error rate of DNA copies a thousandfold. These mechanisms are fundamental to our understanding of how life developed and how it functions at the cellular level.
The technological revolution, it could be argued, started in the 1800s: when scientists were just starting to develop motors, cranks and valves, wholly unaware of the progress their inventions would lead to. Now, we appear to be in a similar place with molecular technology: this nobel prize recognises the development of molecular machines. Sauvage made the first step towards this, developing two ring shaped molecules that form a chain, called a catenane. Unlike most molecules, which are fixed at angles to each other by strong covalent bonds, these catenanes can move relative to each other, which is an integral part of any machinery. Stoddart made the next move: creating a rotaxane: by joining a molecular ring onto an axle he showed the capability for such devices as a molecular lift, a molecular muscle and a molecule-based computer chip. Feringa made the final noted contribution, with his development of a molecular motor. In 1999, he made this motor rotate continuously and move a glass tube which was 10,000 times bigger than the motor itself!
One of the most important methods of understanding biochemistry, is to take images of structures, especially when they are carrying out processes: this allows us to understand how they carry out their function, but electron microscopy was long thought impossible for use with living molecules as it was thought that they would kill any biological material. Frank was the one to make the technology usable for these purposes, transposing the less detailed 2D images it took into full 3D structures. When Henderson found that this wasn’t the case, it opened the door to the use of electron microscopy to fill in gaps left by other methods at our disposal. Dubochet completed the final piece of the puzzle: using vitrified (glass-like solid in structure) water which allowed the molecules to hold their shape. Finally, the door was open to the use of electron microscopy for the imaging of living tissues.
Arnold’s share of the prize, owes to her development of the first (and many later) methods of directed evolution of enzymes. By introducing random mutations in bacteria populations (which produced the enzymes) and then testing the effectiveness of the products, she could essentially speed up evolution to her liking. She later went on to refine her methods to become the industry standard, using for developing catalysts that can help in endeavours to produce chemical substances in a more environmentally friendly manner.
Smith and Winter’s share recognises their directed evolution of antibodies. Smith initially developed the technique called phage display, wherein an organism called a bacteriophage is used to evolve new protein structures. Winter then went on to use this technique on antibodies in an attempt to produce pharmaceutical products. The product of this initial experiment was adalimumab which is used to treat arthritis, psoriasis and inflammatory bowel disease. This sparked a new age of pharmaceuticals: for the first time in our history, we now hold the power of evolution in our hands.
In our everlasting quest to end our reliance on fossil fuels, the lithium-ion battery represents a great step forward towards a sustainable future. Whittingham made the first step: in the 1970s he created the first lithium-ion battery, utilising a titanium disulphide cathode, which facilitated the existence of the lithium ions: conversely, the anode was made from metallic lithium. This yielded a great voltage of 2V, but was too unstable and potentially explosive to be commercially viable. Goodenough took the next step forward, after theorising that use of a metal oxide in the cathode would produce a greater voltage, his search produced cobalt oxide as the best potential candidate, producing voltages up to 4V. Finally, Yoshino created a safe-for-use battery: by replacing the lithium metal in the anode with petroleum coke which can also facilitate and hold lithium ions. This, rather less explosive battery was the first in a new generation, which relied not on a difficult-to-reverse chemical reaction, but merely on the flow of lithium ions between cathode and anode.
2010: Awarded to Robert G. Edwards
“for the development of in vitro fertilization”
This revolutionary new method of conception has changed the way couples have planned families: giving us more control than ever over our lives (and our families). It is one of the only ways to treat/subvert infertility and since it’s first successful use in 1978 it has been refined and become widely used as a method of conception even for those who don’t suffer from infertility.
2011: Awarded to Bruce A. Beutler and Jules A. Hoffmann
“for their discoveries concerning the activation of innate immunity”
Ralph M. Steinman
“for his discovery of the dendritic cell and its role in adaptive immunity”
Contributions to our understanding of the immune system are essential to our ability to combat disease. The prize was awarded to Beutler and Hoffman for their work pertaining to how certain genes/structures (namely the Toll gene in fruit flies and the Toll-like receptors (TLRs) found in mice). Their research led to the discovery of a dozen more TLRs in different organisms including humans. Steinman’s share of the prize was awarded for his discovery and research on the dendritic cell, which is a controller of the activation of T cells (themselves a key element in immune response). This was of particular importance to our understanding of how the immune system avoids targeting the organism it defends.
This prize recognises the contributions to our understanding of the development and life cycles of cells and organisms. Pluripotent, or unspecialised cells, are capable of reproducing and diversifying to become any cell type within an organism. Gurdon’s share of the prize recognises his work which showed that mature (specialised) cells still contained all the genetic information needed to develop a whole organism. Yamanaka’s share recognises his work in showing that specialisation of cells was reversible.
Vesicles transport any molecules produced by cells in the body. They are an essential transport system within the body, but the precise mechanism of how they work with the necessary accuracy was unknown for a long time. Schekman isolated a set of genes necessary for vesicle transport. Rothman revealed how protein structures allow vesicles to transfer their ‘cargo’. Finally, Südhof gained understanding of how signals coordinate vesicles to release their ‘cargo’ with the necessary precision.
The brain has long been the biggest mystery of biology and that fact remains no different today. This prize recognises the discovery of a positioning system in the brain: one of our first hints at understanding higher brain functions. O’Keefe made the first breakthrough; in 1971 he observed that different areas of the hippocampus of a rat’s brain were activated when it occupied different areas of a room. The Mosers followed up on this discovery more than 3 decades later; they discovered ‘grid cells’, which collectively form a coordinate system. Thus, they provide the ability for pathfinding even in complex environments.
2015: Awarded to William C. Campbell and Satoshi Ōmura
“for their discoveries concerning a novel therapy against infections caused by roundworm parasites”
“for her discoveries concerning a novel therapy against Malaria”
Campbell And Ōmura’s work revolved around the isolation of any effective strains of Streptomyces bacteria – which was known to be an effective producer of antibacterials – in an attempt to find any potential active agents. The end product of the process, which involved the testing of large samples taken from the soil (where Streptomyces is found) and subsequent studies on promising strains, was a compound called Avermectin. This compound was later refined into Ivermectin, which was tested on humans and found to have great success in killing parasitic larvae.
Youyou’s work in the fight against malaria was invaluable. At a time when modern methods were seeing declining results, she somewhat counterintuitively turned to more traditional herbal remedies to attempt to treat the disease. After screening potential remedies on malaria-infected animals, she found that Artemisia annua yielded promising yet inconsistent results. Next she extracted the active component Artemisinin and found it to be extremely effective: she had found the first in a family of antimalarial agents that could rapidly kill malaria parasites at an early stage of development.
2016: Awarded to Yoshinori Ohsumi
“for his discoveries of mechanisms for autophagy”
In the 1960s, scientists observed that old cell contents could be destroyed by the surrounding of the cell by a membrane, being transported as vesicles to the lysosome, where they are degraded. Ohsumi’s experiments with yeast led to a new understanding of how the cell recycles its components and the genes necessary for said process. After first identifying this mechanism in yeast, it soon became clear that this mechanism was not unique and is in fact present in many other organisms including humans. Autophagy was shown, from his research, to have fundamental importance to our physiology.
Life on Earth, it appears, is specifically adapted to the Earth’s rotation: the day-night cycle is inexorably tied to the adaptation of life on Earth. Through their studies on fruit flies, the laureates isolated a gene which controls the ‘biological clock’. They next found several protein compounds involved in the mechanism of this biological clock. With great precision, this gene controls behaviour, hormone levels, sleep and metabolism all according to the activity of the period gene: the activation of said gene being subject to environmental factors to do with the day-night cycle. Our physiology is finely tuned to the environment in which we find ourselves.
In the fight against cancer, perhaps the most confounding factor is our stark lack of immune response: cancer cells are near-identical to our own, after all. But this nobel prize recognises a potential new method in the fight against cancer: finally we might engage our immune systems to destroy cancers. Allison and Honjo both independently worked on two different protein structures (CTLA-4 and PD-1 respectively) which were known to inhibit T-cell activities. These ‘brakes’ were disabled with the use of antibodies that would bind to them, thus preventing their function. The clinical trials of these techniques yielded promising results, with some patients’ cancers even going into remission. Finally, we could engage our immune system in the fight against cancer.
Whilst we have been aware of carotid body-controlled rapid adaptation to low oxygen levels (hypoxia) since the 1800s, albeit with lesser depth of understanding than we have now, we went wholly unaware of the many other mechanisms by which the body responds to available O2 levels. The newly discovered mechanisms by which the body responds to O2 levels are centred around the hypoxia-inducible factor (HIF): HIF is a protein complex which binds to a DNA segment which controls the hypoxia response. Further observation revealed the key interaction: being that of HIF-1α and von Hippel-Lindau’s disease (VHL disease: this is a disease that increases risk of certain cancers). VHL is itself a gene which codes a protein that prevents cancers. This clued researchers in that VHL was closely linked to hypoxia. This was confirmed when two separate studies showed than under normal O2 levels, HIF-1α proteins gain two hydroxyl groups in specific locations: this change allows VHL to bind to it, thus allowing for varying responses, based on O2 availablility.
- https://www.nobelprize.org/prizes/lists/all-nobel-prizes (see also summaries, press releases and any publications referenced therein for particular prizes)