The 2016 Nobel Prize in Physics has been awarded to Michael Kosterlitz, Duncan Haldane and David J. Thouless for work on topological phase transitions, largely published in the 1970s and early 1980s. All three men were born in the UK.

This year’s Laureates opened the door on an unknown world where matter can assume strange states. They have used advanced mathematical methods to study unusual phases, or states, of matter, such as superconductors, superfluids or thin magnetic films. Thanks to their pioneering work, the hunt is now on for new and exotic phases of matter. Many people are hopeful of future applications in both materials science and electronics.

The three Laureates’ use of topological concepts in physics was decisive for their discoveries. Topology is a branch of mathematics that describes properties that only change step-wise. Using topology as a tool, they were able to astound the experts. In the early 1970s, Michael Kosterlitz and David Thouless overturned the then current theory that superconductivity or suprafluidity could not occur in thin layers. They demonstrated that superconductivity could occur at low temperatures and also explained the mechanism, phase transition, that makes superconductivity disappear at higher temperatures.

In the 1980s, Thouless was able to explain a previous experiment with very thin electrically conducting layers in which conductance was precisely measured as integer steps. He showed that these integers were topological in their nature. At around the same time, Duncan Haldane discovered how topological concepts can be used to understand the properties of chains of small magnets found in some materials.

Kosterlitz and Thouless
http://iopscience.iop.org/article/10.1088/0022-3719/6/7/010/meta;jsessionid=C29DC2BC7B230E81C1ED0507B03F0652.c4.iopscience.cld.iop.org
Ordering, metastability and phase transitions in two-dimensional systems

Japanese researcher Yoshinori Ohsumi has won the 2016 Nobel Prize for Physiology or Medicine for work on cellular autophagy. The relevant work was conducted in the mid-nineties which is fairly recent for work being recognised with an NP.

This year’s Nobel Laureate discovered and elucidated mechanisms underlying autophagy, a fundamental process for degrading and recycling cellular components.

The word autophagy originates from the Greek words auto-, meaning “self”, and phagein, meaning “to eat”. Thus,autophagy denotes “self eating”. This concept emerged during the 1960’s, when researchers first observed that the cell could destroy its own contents by enclosing it in membranes, forming sack-like vesicles that were transported to a recycling compartment, called the lysosome, for degradation. Difficulties in studying the phenomenon meant that little was known until, in a series of brilliant experiments in the early 1990’s, Yoshinori Ohsumi used baker’s yeast to identify genes essential for autophagy. He then went on to elucidate the underlying mechanisms for autophagy in yeast and showed that similar sophisticated machinery is used in our cells.

Ohsumi’s discoveries led to a new paradigm in our understanding of how the cell recycles its content. His discoveries opened the path to understanding the fundamental importance of autophagy in many physiological processes, such as in the adaptation to starvation or response to infection. Mutations in autophagy genes can cause disease, and the autophagic process is involved in several conditions including cancer and neurological disease.

dv said:

The 2016 Nobel Prize in Physics has been awarded to Michael Kosterlitz, Duncan Haldane and David J. Thouless for work on topological phase transitions, largely published in the 1970s and early 1980s. All three men were born in the UK.

This year’s Laureates opened the door on an unknown world where matter can assume strange states. They have used advanced mathematical methods to study unusual phases, or states, of matter, such as superconductors, superfluids or thin magnetic films. Thanks to their pioneering work, the hunt is now on for new and exotic phases of matter. Many people are hopeful of future applications in both materials science and electronics.

The three Laureates’ use of topological concepts in physics was decisive for their discoveries. Topology is a branch of mathematics that describes properties that only change step-wise. Using topology as a tool, they were able to astound the experts. In the early 1970s, Michael Kosterlitz and David Thouless overturned the then current theory that superconductivity or suprafluidity could not occur in thin layers. They demonstrated that superconductivity could occur at low temperatures and also explained the mechanism, phase transition, that makes superconductivity disappear at higher temperatures.

In the 1980s, Thouless was able to explain a previous experiment with very thin electrically conducting layers in which conductance was precisely measured as integer steps. He showed that these integers were topological in their nature. At around the same time, Duncan Haldane discovered how topological concepts can be used to understand the properties of chains of small magnets found in some materials.

Kosterlitz and Thouless
http://iopscience.iop.org/article/10.1088/0022-3719/6/7/010/meta;jsessionid=C29DC2BC7B230E81C1ED0507B03F0652.c4.iopscience.cld.iop.org
Ordering, metastability and phase transitions in two-dimensional systems

Well, that was unexpected. By the way, that’s not the famous Haldane (J.B.S.) or the famous Thouless (Robert H.)

Looking at the paper.

“Peierls (1935) has argued that thermal motion of long-wavelength phonons will destroy
the long-range order of a two-dimensional solid in the sense that the mean square
deviation of an atom from its equilibrium position increases logarithmically with the
size of the system. Similar arguments can be used to
show that there is no spontaneous magnetization in a two-dimensional magnet with
spins with more than one degree of freedom and that the
expectation value of the superfluid order parameter in a two-dimensional Bose fluid
is zero.”

“In this paper we present arguments in favour of a quite different definition of long range
order which is based on the overall properties of the system rather than on the
behaviour of a two-point correlation function. This type of
long-range order, which we refer to as topological long-range order, may exist for the
two-dimensional solid, neutral superfluid, and for the xy model, but not for a superconductor
or isotropic Heisenberg model. The definition of long-range order which we adopt arises
naturally in the case of a solid from the dislocation theory of melting.
This theory is much easier to apply in two dimensions
than in three since a dislocation is associated with a point rather than a line. At high
temperatures, dislocations will appear spontaneously when the entropy term takes over.
The critical temperature at which a single dislocation is likely to occur is the temperature
at which the free energy changes sign.”

Is this worth a Nobel prize?

mollwollfumble said:

Is this worth a Nobel prize?

Maybe it was a matter of being the only contenders this year still alive?

The2016 Chemistry Prize was awarded jointly to Jean-Pierre Sauvage, Sir J. Fraser Stoddart and Bernard L. Feringa “for the design and synthesis of molecular machines”.

The development of computing demonstrates how the miniaturisation of technology can lead to a revolution. The 2016 Nobel Laureates in Chemistry have miniaturised machines and taken chemistry to a new dimension.

The first step towards a molecular machine was taken by Jean-Pierre Sauvage in 1983, when he succeeded in linking two ring-shaped molecules together to form a chain, called a catenane. Normally, molecules are joined by strong covalent bonds in which the atoms share electrons, but in the chain they were instead linked by a freer mechanical bond. For a machine to be able to perform a task it must consist of parts that can move relative to each other. The two interlocked rings fulfilled exactly this requirement.

The second step was taken by Fraser Stoddart in 1991, when he developed a rotaxane. He threaded a molecular ring onto a thin molecular axle and demonstrated that the ring was able to move along the axle. Among his developments based on rotaxanes are a molecular lift, a molecular muscle and a molecule-based computer chip.

Bernard Feringa was the first person to develop a molecular motor; in 1999 he got a molecular rotor blade to spin continually in the same direction. Using molecular motors, he has rotated a glass cylinder that is 10,000 times bigger than the motor and also designed a nanocar.

https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/press.html